TY - CONF A1 - Kadoke, Daniel T1 - Optische Verformungsmessung im Dienste Technischer Sicherheit N2 - Ausgehend vom sicherheitsbezogenen Aufgabenspektrum der BAM konzentriert sich das Poster auf die messtechnischen Verfahrensgrundlagen und Anwendungsbeispiele aus den Bereichen der experimentellen Bauartprüfung von RAM-Behältern in Fallprüfungen mit Wordt-Case-Szenarien, der Schadensanalyse und der Mitwirkung in F/E-Projekten T2 - 3D-NordOst 2019 CY - Berlin, Germany DA - 05.12.2019 KW - Fallprüfung KW - Verformungsanalyse KW - Stereo-Kamera KW - Verschiebungsmessung PY - 2019 AN - OPUS4-50030 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CHAP A1 - Meftah, F. A1 - Pesavento, F. A1 - Davie, C. A1 - Dal Pont, S. A1 - Zeiml, M. A1 - Korzen, Manfred A1 - Millard, A. ED - Millard, A. ED - Pimienta, P. T1 - Advanced Modelling N2 - In this chapter, advanced models based on a General thermo-Hydro-Mechanical (THCM) Framework are considered. In These approaches, the concrete is considered as a porous medium, the pores of which are partly filled by gas (a mixture of air and vapour) and water. KW - Concrete KW - High temperature KW - Stress-strain-relation PY - 2019 SN - 978-3-030-11994-2 SN - 978-3-030-11995-9 DO - https://doi.org/10.1007/978-3-030-11995-9 SN - 2213-204X SN - 2213-2031 SP - 27 EP - 65 PB - Springer CY - Cham, Switzerland AN - OPUS4-50174 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schneider, I. A1 - Kebelmann, Katharina A1 - Risse, S. A1 - Dieguez-Alonso, A. A1 - Schartel, Bernhard A1 - Strecker, C. A1 - Behrendt, F. T1 - Hydroliquefaction of Two Kraft Lignins in a Semibatch Setup under Process Conditions Applicable for Large-Scale Biofuel Production N2 - Hydroliquefaction is a possible pathway to produce liquid transportation fuels from solid feedstocks like coal or biomass. Though much effort has been put into the investigation of maximizing the oil yield using expensive catalysts and pasting oils in batch setups, little is known about how to commercialize the process. This work aims at the demonstration of lignin hydroliquefaction under conditions interesting for commercial operation. The results from hydroliquefaction experiments of two different lignin types using a cheap iron-based catalyst and anthracene oil as the pasting oil in a semibatch system are presented here. Oil yields of above 50% are reached without observing coke formation. Extensive analyses of the feedstocks and product oils were performed. The process supplies high-quality oil, while differences in the decomposition path of both lignin types are observed. An high heating value of 39 400 J/g and H/C and O/C ratios of up to 1.6 and 0.1, respectively, are detected for the produced bio-oils. KW - Lignin KW - Hydroliquefaction KW - Biofuel PY - 2019 DO - https://doi.org/10.1021/acs.energyfuels.9b02572 SN - 0887-0624 SN - 1520-5029 VL - 33 IS - 11 SP - 11057 EP - 11066 PB - ACS AN - OPUS4-50102 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Tomiak, F. A1 - Schartel, Bernhard A1 - Wolf, M. A1 - Drummer, D. T1 - Particle Size Related Effects of Multi-Component Flame-Retardant Systems in poly(butadiene terephthalate) N2 - Aluminum tris (diethylphosphinate) (AlPi) is known to have an efficient flame-retardant effect when used in poly(butadiene terephthalates) (PBT). Additionally, better flame-retardant effects can be achieved through the partial substitution of AlPi by boehmite in multi-component systems, which have been shown to be an effective synergist due to cooling effects and residue formation. Although the potential of beneficial effects is generally well known, the influence of particle sizes and behavior in synergistic compositions are still unknown. Within this paper, it is shown that the synergistic effects in flammability measured by limiting oxygen index (LOI) can vary depending on the particle size distribution used in PBT. In conducting thermogravimetric analysis (TGA) measurements, it was observed that smaller boehmite particles result in slightly increased char yields, most probably due to increased reactivity of the metal oxides formed, and they react slightly earlier than larger boehmite particles. This leads to an earlier release of water into the system enhancing the hydrolysis of PBT. Supported by Fourier transformation infrared spectroscopy (FTIR), we propose that the later reactions of the larger boehmite particles decrease the portion of highly flammable tetrahydrofuran in the gas phase within early burning stages. Therefore, the LOI index increased by 4 vol.% when lager boehmite particles were used for the synergistic mixture. KW - Flame retardants KW - Aluminum diethylphosphinate KW - Boehmite KW - Poly(butadiene terephthalates) (PBT) KW - Mechanical properties PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-509286 DO - https://doi.org/10.3390/polym12061315 SN - 2073-4360 VL - 12 IS - 6 SP - 1315 PB - MDPI AN - OPUS4-50928 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Bäßler, Ralph T1 - Rezension: Zerstörungsfreie Werkstück- und Werkstoffprüfung N2 - Das 1988 erstmalig erschienene und bewährte Fachbuch wurde auf den neuesten Stand gebracht und im Rahmen der „Kontakt & Studium“‐Serie der Technischen Akademie Esslingen als Band 243 neu aufgelegt. In 12 Kapiteln bieten die 12 erfahrenen Autoren einen Überblick über die gebräuchlichsten Formen zerstörungsfreier Prüfverfahren als Grundlage für die Dokumentation der Produktqualität während des gesamten Herstellungsprozesses und deren elementare Bedeutung für die Produkthaftung. Dieses Lehrbuch dient nicht nur Universitäts‐Studierenden, sondern bietet auch jedem interessierten Leser einen Überblick der gebräuchlichen Verfahren. KW - Werkstoffprüfung KW - ZFP PY - 2020 DO - https://doi.org/10.1002/maco.202070076 SN - 1521-4176 SN - 0947-5117 VL - 71 IS - 7 SP - 3 PB - WILEY‐VCH Verlag GmbH & Co. KGaA CY - Weinheim AN - OPUS4-50959 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Bäßler, Ralph T1 - Review: Magnesium and its Alloys – Technology and Applications N2 - The first edition of this book, published within the series “Materials Science – Metals and Alloys”, provides broad knowledge of this interesting and widely applied metal from manufacturing and production to finishing and application in 13 chapters, written by 29 contributors. Each chapter is separately concluded and ends with references used. This book fulfills its intention of conveying comprehensive and cutting‐edge knowledge of magnesium alloys. It is useful for practicing engineers, researchers and students searching for an instructional and reference source. KW - Magnesium KW - Magnesium Alloy PY - 2020 DO - https://doi.org/10.1002/maco.202070074 SN - 1521-4176 SN - 0947-5117 VL - 71 IS - 7 SP - 1229 EP - 1230 PB - WILEY‐VCH Verlag GmbH & Co. KGaA CY - Weinheim AN - OPUS4-50960 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Palis, Stephan A1 - Sträubig, Felix A1 - Voigt, Sascha A1 - Knaust, Christian T1 - Experimental investigation of the impact of water mist on high-speed non-premixed horizontal methane jet fires N2 - In this paper, the influence of a fixed water mist firefighting system on a high-speed non-premixed horizontal methane jet fire is investigated with focus on its effect on temperatures and heat load of the jet fire and on ist surroundings. Six tests are performed in which gas is released out of an orifice with a diameter of 1 mm and a release pressure of up to 186 bar. In addition to temperature and radiation measurements, the release pressure, gas mass flow rate and exhaust gas concentrations are detected to determine the heat release. Video and IRanalysis are used to evaluate the interactions between jet fire and water mist. The experiments show, that water mist reduces the temperatures inside the jet fire flow field and its radiative heat flux. It can lower the Risk of ignition of adjacent surfaces and materials, as temperatures fall below autoignition temperatures of common materials like plastics. Although water mist does not extinguish the fire, it has an impact on the energy release by reducing combustion efficiency due to heat exchange with the water mist and oxygen displacement. KW - Fixed firefighting system KW - Jet fire KW - Water mist KW - Fire test KW - Methane KW - Supersonic flow PY - 2020 DO - https://doi.org/10.1016/j.firesaf.2020.103005 VL - 114 SP - 103005 PB - Elsevier Ltd. AN - OPUS4-50963 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Voigt, Sascha A1 - Sträubig, Felix A1 - Palis, Stephan A1 - Kwade, A. A1 - Knaust, Christian T1 - CFD-analysis of Sensible Enthalpy Rise Approach to determine the heat release rate of electric-vehicle-scale lithium-ion batteries N2 - This paper analyses the suitability of the Sensible Enthalpy Rise Approach for measuring the heat release rate of electric-vehicle-scale lithium-ion batteries. An apparatus is designed that meets the conditions of an electric-vehicle-scale lithium-ion battery fire by using cement board as wall material. Modifications of the Sensible Enthalpy Rise Methodology are presented due to the high emissivity and inhomogeneous temperature distribution of the apparatus wall material: a power 4 approach for the heat flow from the walls to the ambient air and an alternative determination methodology for the wall temperature. A one factor at a time parameter study is performed with Computational Fluid Dynamics simulations, investigating a new calibration method based on a fit approach compared to common methods, the wall temperature determination, the approach for the ambient heat flow, the calibration power and the volume flow at the outlet. The simulations show, that suitable estimations of the heat release rate are obtained by using the modifications for wall temperature determination and the power 4 approach for the ambient heat flow. The three calibration methods provide suitable constants, if the calibration power in the same order of magnitude as the mean of the heat release rate profile of the test object. KW - Lithium-ion batteries KW - Heat Release Rate KW - Calorimetry KW - Sensible Enthalpy Rise Approach KW - Computational Fluid Dynamics PY - 2020 DO - https://doi.org/10.1016/j.firesaf.2020.102989 VL - 114 SP - 1 EP - 14 PB - Elsevier Ltd. AN - OPUS4-50964 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rica, S. A1 - Van Baars, S. A1 - Kullolli, Borana ED - Ülgen, D. ED - Saygili, A. ED - Kahyaoglu, M. R. ED - Durmaz, S. ED - Toygar, O. ED - Göcügenci, A. T1 - The importance of the horizontal stresses on the bearing capacity of a foundation pile N2 - In case one wants to predict or design the bearing capacity of a foundation pile and there are no possibilities to perform an in-situ test, such as a Cone Penetration Test, the pile bearing capacity is in most cases estimated with analytical formulas. The most known and used method is the Meyerhof method published some decades ago. There are also other design methods such as derived from a certain failure mechanism around the pile tip, which is, in most cases, wedge failure mechanism. This failure mechanism was originally developed for a shallow (infinite) strip foundation, though. Therefore, it represents a plane failure mechanism. Numerical simulations on loaded foundation piles performed with the Plaxis software Show however, that the failure mechanism of a foundation pile represents a far more complex threedimensional failure mechanism around the pile tip. In addition, the existing analytical methods for foundation piles are based on the vertical stresses in the soil, as if the failure mechanism is the same as of a shallow foundation. Numerical simulations, performed in Plaxis show that, not the vertical, but the horizontal stresses, play an important role on the pile bearing capacity. Plaxis represents the stresses in the soil by using the procedure. So, different horizontal soil stresses are obtained for different values of the lateral earth pressure coefficient. The results show that the pile tip bearing capacity depends strongly on the horizontal stresses in the soil, but only for. The same results were observed by using a Material Point Method (MPM). Consequently, the analytical methods should estimate the pile bearing. T2 - 1st Mediterranean Young Geotechnical Engineers Conference CY - Bodrum, Turkey DA - 23.09.2019 KW - Analytical Design Methods KW - Foundation Pile KW - Horizontal stress PY - 2019 UR - http://mygec2019.org/ VL - 2019 SP - 151 EP - 158 PB - 1st Mediterranean Young Geotechnical Engineers Conference CY - Bodrum, Turkey AN - OPUS4-49639 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kratzig, Andreas A1 - Bettge, Dirk A1 - Le, Quynh Hoa A1 - Bäßler, Ralph A1 - Kranzmann, Axel T1 - Interaction of Oxidizing and Reductive Components in CO2 Streams with Transport Pipeline Steel X70 at High Pressure and Low Temperature N2 - Specific amounts of oxidizing and reductive impurities as well as some moisture were added to dense phase CO2 to replicate CO2 streams from sources in a CCS pipeline network. Due to the moisture content being only 50 ppmV no visible acid condensation took place. To simulate stress conditions at the inside pipeline surface due to fluid pressure (10 MPa) specimens were preloaded using a load frame. Experiments conducted at 278 K and at 313 K revealed the highest corrosion rate at lower temperature. Corrosive effect of impurities was strongest applying mixed atmosphere, containing oxidizing and reductive components, closely followed by CO2 streams with pure oxidizing character. By far, the lowest corrosion rate (10x lower) resulted from reductive atmosphere. In general, at constant temperature and pressure the CO2 stream composition strongly influences the morphology, thickness and composition of the corrosion products. Applying oxidizing or mixed impurities, iron hydroxides or oxides (e.g. goethite, hematite) occur as dominating corrosion products, capable to incorporate different amounts of sulfur. In contrast, using reductive atmosphere very thin corrosion layers with low crystallinity were developed, and phase identification by XRD was unfeasible. SEM/EDX analysis revealed the formation of Fe-O compounds, most likely attributed to the oxygen partial pressure in the system induced by CO2 (≥0.985 volume fraction) and volatile H2O. In addition to the surface covering corrosion layer, secondary phases had grown locally distributed on top of the layer. These compounds are characteristic for the applied atmosphere and vary in number, shape and chemical composition. T2 - 14th Greenhouse Gas Control Technologies Conference (GHGT-14) CY - Melbourne, Australia DA - 21.10.2018 KW - CCS KW - CO2 Corrosion KW - Pipelines PY - 2019 UR - https://ssrn.com/abstract=3365756 VL - 2019 SP - 1 EP - 15 AN - OPUS4-49711 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Aristia, Gabriela T1 - Fireside Chat - Sharing PhD N2 - Erfahrung einer indonesischen Stipendiatin beim Aufenthalt in Deutschland als Doktorandin; Hinweise und Empfehlungen für indonesische Jungwissenschaftler und Studenten T2 - Fireside Chat der Indonesischen Botschaft CY - Berlin, Germany DA - 21.11.2019 KW - Indonesien PY - 2019 AN - OPUS4-49737 LA - mul AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Markwart, J. C. A1 - Battig, Alexander A1 - Kuckhoff, T. A1 - Schartel, Bernhard A1 - Wurm, F. R. T1 - First phosphorus AB2 monomer for flame-retardant hyperbranched polyphosphoesters: AB2vs. A2 + B3 N2 - Branched polymers are an important class of polymers with a high number of terminal groups, lower viscosity compared to their linear analogs and higher miscibility, which makes them especially interesting for flame retardant applications, where the flame retardants (FR) are blended with another polymer matrix. Hyperbranched polyphosphoesters (hbPPEs) are gaining more and more interest in the field of flame retardancy, as low molar mass FRs often have the disadvantage of blooming out or leaching, which is not desired in consumer products. Here, we present the first phosphorus-based AB2 monomer for the synthesis of hbPPEs and assess its flame-retardant performance in an epoxy resin compared to a hbPPE synthesized by an A2 + B3 approach. The hbPPE synthesized from an AB2 monomer exhibited a slightly higher performance compared to a similar hbPPE, which was prepared by A2 + B3 polyaddition, probably due to its higher phosphorus content. KW - Polyphosphoester KW - Hyperbranched KW - Flame retardant KW - Synthesis PY - 2019 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-497570 DO - https://doi.org/10.1039/c9py01156k SN - 1759-9962 VL - 10 IS - 43 SP - 5920 EP - 5930 PB - RSC AN - OPUS4-49757 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schartel, Bernhard T1 - Flammschutzmechanismen in der Kunststofftechnik N2 - The main flame retardant modes of action are known, nevertheless in practise the detailed scientific understanding usually falls short, when it comes to modern multicomponent systems, the important tiny optimizations, or quantifying in terms of specific fire properties. The description of the flame retardant modes of action remains usually vague and fragmentary. This talk tries to deliver thought-provoking impulses how the understanding of the fire behaviour and flame retardancy can be utilized to direct the development of future flame retardant polymer products. Some overseen details are picked up as well as rethinking of concepts memorised long ago is encouraged to discover something new. Furthermore, the talk tries to fill the gap between flame retardant modes of action and fire performance constituting a product. This talk promotes the evidence-based development of flame retardant polymers. T2 - VDI-Vortrag, AK “Kunststofftechnik” des VDI-Bezirksverein Nürnberg e.V. CY - Erlangen, Germany DA - 20.11.2019 KW - Modes of action KW - Flame retardancy KW - Charring KW - Flame inhibition KW - Fuel dilution KW - Protective layer PY - 2019 AN - OPUS4-49759 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bäßler, Ralph T1 - Review: Introduction to Materials for Advanced Energy Systems N2 - Since materials play an important role when designing and servicing industrial facilities. Also, for energy systems there is no way around. Selection of appropriate materials is an essential aspect for successful application and reliable service life. Future engineers must be made aware on the importance of this fact. So, they may prevail in techno‐economic discussions. The book fulfills its intension of providing to students in science and engineering a comprehensive understanding of different energy processes and what role materials play in this conjunction. Also, it gives interested engineers and scientists an insight in this matter. After being introduced the user should dig deeper in the existing detailed knowledge available for materials selection within these special conditions to assure a reliable operation of the energy production facility. KW - Energy systems KW - Materials PY - 2019 DO - https://doi.org/10.1002/maco.201970114 SN - 1521-4176 SN - 0947-5117 VL - 70 IS - 11 SP - 2140 EP - 2141 PB - WILEY‐VCH Verlag GmbH & Co. KGaA CY - Weinheim AN - OPUS4-49719 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Mundra, Shishir A1 - Prentice, D. P. A1 - Bernal, S. A. A1 - Provis, J. L. T1 - Modelling chloride transport in alkali-activated slags N2 - The service-life of steel-reinforced concrete structures is primarily determined by the ability of the concrete cover to resist chloride ingress. With limited literature available on the ingress of chloride into alkali-activated slags (AAS) under service conditions, it is critical that this is described by appropriate models. This paper describes an interactive software framework to relate chloride ingress into AAS with the chemistry of the concrete cover, by considering the chloride binding capacity and porosity of the binder as a function of time, based on thermodynamic calculations of the phase assemblage as a function of slag and activator composition. This provides a major step towards developing the ability to predict the ingress of chlorides in alkali-activated concretes from a sound theoretical basis, which is essential in providing confidence in the durability of these materials in essential infrastructure applications. KW - Thermodynamic calculations KW - Alkali activated cement KW - Durability KW - Diffusion KW - Chloride PY - 2020 DO - https://doi.org/10.1016/j.cemconres.2020.106011 VL - 130 SP - 106011 PB - Elsevier Ltd. AN - OPUS4-50423 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Beck, Joana T1 - Rezension: Konformität von Produkten ‐ Gesetzliche Anforderungen, Konformitätsbewertungen, Konformitätsdokumente, Prüfbescheinigungen N2 - Im europäischen Warenhandel kommt es durch immer mehr EU‐Vorschriften und damit verbundener Verschärfung gesetzlicher Anforderungen zu deutlich höherer Nachfrage von Konformitätserklärungen. Davon hängt nicht nur die Sicherheit der Endverbraucher sondern überhaupt die Einfuhrerlaubnis für Produkte ab. Um in diesem Wirrwarr an Regularien herauszufinden, welchen Vorschriften ein spezielles Produkt unterliegt und welche Konformitätsdokumente von wem auszustellen sind, gibt der Autor mit diesem Buch einen ersten Überblick zu den derzeit existierenden Regularien und den geforderten Konformitätsdokumenten. Auch wenn das Buch sich nicht unbedingt als Leitfaden für Produkthersteller eignet, hat der Autor hier zahlreiche nützliche Informationen zur Konformität von Produkten zusammengetragen und interpretiert, um dem Leser etwas Durchblick auf diesem komplexen Gebiet zu verschaffen. KW - Konformität KW - Qualitätsmanagement PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-503731 DO - https://doi.org/10.1002/maco.202070026 SN - 1521-4176 SN - 0947-5117 VL - 71 IS - 2 SP - 3 PB - WILEY‐VCH Verlag GmbH & Co. KGaA CY - Weinheim AN - OPUS4-50373 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Morys, Michael A1 - Häßler, Dustin A1 - Krüger, Simone A1 - Schartel, Bernhard A1 - Hothan, Sascha T1 - Beyond the standard time-temperature curve: Assessment of intumescent coatings under standard and deviant temperature curves N2 - Nowadays there are intumescent coatings available for diverse applications. There is no established assessment of their protection performance besides the standard time-temperature curve, but natural fire scenarios often play an important role. A reliable straightforward performance-based assessment is presented. The effective thermal conductivity per thickness is calculated based on intermediate-scale fire tests. The optimum thermal insulation, the time to reach it, and the time until contingent failure of the coating are used for an assessment independent of the heating curve. The procedure was conducted on four different commercially intumescent coatings for steel construction, one solvent-based, one waterborne, one epoxy-based, and a bandage impregnated with a waterborne coating. The performance was studied under four different but similar shaped heating curves with different maximum temperatures (standard time-temperature curve, hydrocarbon curve and two self-designed curves with reduced temperature). The thermal protection performance is crucially affected by the residue morphology. Therefore, a comprehensive morphology analysis, including micro-computed tomography and scanning electron microscopy, was conducted on small-scale residues (7.5 x 7.5 cm2). Two different types of inner structures and the residue surface after different heat exposures were discussed in terms of their influence on thermal protection performance. KW - Intumescence KW - Coating KW - Computed tomography KW - Small scale KW - Heating curves KW - Residue morphology PY - 2020 DO - https://doi.org/10.1016/j.firesaf.2020.102951 SN - 0379-7112 VL - 112 SP - 102951 PB - Elsevier Ltd. AN - OPUS4-50334 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hu, W.-H A1 - Tang, D.-H. A1 - Wang, M. A1 - Liu, J.-L. A1 - Li, Z.-H. A1 - Lu, W. A1 - Teng, J. A1 - Said, Samir A1 - Rohrmann, R. G. T1 - Resonance Monitoring of a Horizontal Wind Turbine by Strain-Based Automated Operational Modal Analysis N2 - A strain-based automated operational modal analysis algorithm is proposed to track the long-term dynamic behavior of a horizontal wind turbine under operational conditions. This algorithm is firstly validated by a scaled wind turbine model, and then it is applied to the dynamic strain responses recorded from a 5 MW wind turbine system. We observed variations in the fundamental frequency and 1f, 3f excitation frequencies due to the mass imbalance of the blades and aerodynamic excitation by the tower dam or tower wake. Inspection of the Campbell diagram revealed that the adverse resonance phenomenon and Sommerfeld effect causing excessive vibrations of the wind tower. KW - Strain KW - Automated operational modal analysis KW - Resonance KW - Horizontal wind turbine PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-503350 DO - https://doi.org/10.3390/en13030579 VL - 13 IS - 3 SP - 579 EP - 584 PB - MDPI CY - Schweiz, Basel AN - OPUS4-50335 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Frei, Vivian A1 - Thiele, Marc A1 - Pirskawetz, Stephan A1 - Meng, Birgit A1 - Rogge, Andreas T1 - Characterizing the Fatigue Behavior of High-Performance Concrete for Wind Energy Structures N2 - Severe mechanical fatigue conditions for worldwide proliferating windfarms are a Major challenge for high-performance concrete in towers, connecting joints and foundations of wind turbines. High-performance concrete offers potential for the application in offshore windfarms, not only regarding its good mechanical, but also chemical resistivity due to low diffusivity in the highly densified microstructure. For a more reliable fatigue assessment, monitoring based on nondestructive testing can be a valuable complement to design rules. Both approaches demand reliable experimental data, information about scalability and the development of standardized testing methods. This article presents results of an ongoing research program of BAM (Bundesanstalt für Materialforschung und -prüfung), which is a part of a joint national project (WinConFat) funded by the German Federal Ministry for Economic Affairs and Energy. The subproject implemented by BAM examines the fatigue behavior in dependence of size and slenderness for varying concrete strength at different stress levels. Besides fatigue strength, nondestructive testing is carried out additionally. Methods used are strain measurement and ultrasonic testing. The change of strain, stiffness and ultrasonic pulse velocity in the fatigue process is discussed. Results disclose a deeper insight into the damage process under cyclic loading of high-performance concrete and contribute to improve nondestructive monitoring. T2 - LORCENIS - Long Lasting Reinforced Concrete fpr Energy Infrastructure under Severe Operating Conditions CY - Ghent, Belgium DA - 10.09.2019 KW - Compressive Cyclic loading KW - Fatigue KW - High-strength concrete KW - Non destructive testing KW - Ultrasonic testing PY - 2019 SN - 978-9-463-88638-3 SP - 1 EP - 4 AN - OPUS4-49500 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Long, Lijia A1 - Döhler, M. A1 - Thöns, Sebastian T1 - Determination of structural and damage detection system influencing parameters on the value of information N2 - A method to determine the influencing parameters of a structural and damage detection system is proposed based on the value of Information analysis. The value of information analysis utilizes the Bayesian pre-posterior decision theory to quantify the value of damage detection system for the structural integrity management during service life. First, the influencing parameters of the structural system, such as deterioration type and rate are introduced for the performance of the prior probabilistic system model. Then the influencing parameters on the damage detection system performance, including number of sensors, sensor locations, measurement noise, and the Type-I error are investigated. The preposterior probabilistic model is computed utilizing the Bayes’ theorem to update the prior system model with the damage indication information. Finally, the value of damage detection system is quantified as the difference between the maximum utility obtained in pre-posterior and prior analysis based on the decision tree analysis, comprising structural probabilistic models, consequences, as well as benefit and costs analysis associated with and without monitoring. With the developed approach, a case study on a statically determinate Pratt truss bridge girder is carried out to validate the method. The analysis shows that the deterioration rate is the most sensitive parameter on the effect of relative value of information over the whole service life. Furthermore, it shows that more sensors do not necessarily lead to a higher relative value of information; only specific sensor locations near the highest utilized components lead to a high relative value of information; measurement noise and the Type-I error should be controlled and be as small as possible. An optimal sensor employment with highest relative value of information is found. Moreover, it is found that the proposed method can be a powerful tool to develop optimal service life maintenance strategies—before implementation—for similar bridges and to optimize the damage detection system settings and sensor configuration for minimum expected Costs and risks. KW - Damage detection systems KW - Value of information KW - Deteriorating structures KW - Probability of damage indication KW - Decision theory PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-508083 DO - https://doi.org/10.1177/1475921719900918 SN - 1475-9217 SN - 1741-3168 VL - 21 IS - 1 SP - 19 EP - 36 PB - Sage Publications CY - Thousand Oaks, Calif. AN - OPUS4-50808 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bayane, I. A1 - Long, Lijia A1 - Thöns, Sebastian A1 - Brühwiler, E. T1 - Quantification of the conditional value of SHM data for the fatigue safety evaluation of a road viaduct N2 - Fatigue safety verification of existing bridges that uses ‘‘re-calculation’’ based on codes, usually results in insufficient fatigue safety, triggering invasive interventions. Instead of “re-calculation”, Structural Health Monitoring (SHM) should be used for the assessment of the existing bridges. Monitoring systems provide data that can reduce uncertainties associated with the fatigue loading process and the structural resistance. The objective of this paper is to quantify the value of the SHM system implemented in a 60-years-old road viaduct to investigate its fatigue safety, through modeling of the fundamental decisions of performing monitoring in conjunction with its expected utility. The quantification of the conditional value of information is based on the decision tree analysis that considers the structural reliability, various decision scenarios as well as the cost-benefit assessments. This leads to a quantitative decision basis for the owner about how much time and money can be saved while the viaduct fulfills its function reliably and respects the safety requirements. The originality of this paper stands in the application of the value of information theory to an existing viaduct considering the fatigue failure of the system based on the monitoring data and the cost-benefit of monitoring method. T2 - 13th International Conference on Applications of Statistics and Probability in Civil Engineering CY - Seoul, South Korea DA - 26.05.2019 KW - Fatigue safety KW - Value of information PY - 2019 SP - 275 EP - 288 CY - Seoul, South Korea AN - OPUS4-50809 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Mietz, Jürgen A1 - Burkert, Andreas T1 - Selection and Durability of Stainless Steels for Civil Engineering N2 - Due to the large number of stainless steels with different chemical composition and different microstructure the selection of the suitable material represents a huge challenge. In order to facilitate the appropriate grade selection, in the current European standard EN 1993-1-4 a procedure is defined based on the use of a look-up table considering the key variables that influence the selection of stainless steels. The table uses descriptions that competent designers should be able to readily understand or define without prior knowledge. The output from the look-up table is used to select alloys based on a Corrosion Resistance Class (CRC) from I to V. The advantage of this approach is that the designer simply specifies the relevant CRC and does not need to consider in detail which of the many (very similar) alloys to specify. KW - Corrosion resistance KW - Stainless steel KW - Civil engineering KW - Atmospheric corrosion PY - 2020 DO - https://doi.org/10.4028/www.scientific.net/KEM.843 SN - 1662-9795 VL - 843 SP - 125 EP - 131 PB - Trans Tech Publications Ltd, CY - Switzerland AN - OPUS4-50831 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Bäßler, Ralph T1 - Rezension: Halliday Physik für natur‐ und ingenieurwissenschaftliche Studiengänge – Lehr‐ und Übungsbuch N2 - Die von Stephan W. Koch herausgegebene Übersetzung der erweiterten zehnten Auflage von ,,Fundamentals of Physics“ liefert ein Schwergewicht geballten Physikwissens und Übungsmaterial. Die Bücher bieten nicht nur Studierenden hilfreiches Lernmaterial, sondern sind auch für allgemein Physik‐Interessierte ein wertvolles Nachschlagewerk. Wer sich bereits mit dem umfassenderen „großen Bruder“ vertraut gemacht hat und diesen nutzt, findet im Lehrbuch nichts Neues. Jedoch liefert das Übungsbuch im Vergleich zum Arbeitsbuch von 2018 neue und übersichtlichere Übungsbeispiele. Die neue Auflage wurde didaktisch komplett neu strukturiert und einige Kapitel vollständig überarbeitet. Ein Novum stellt dabei die modulare Organisation dar, bei der jeder Abschnitt mit Lernzielen und Schlüsselideen beginnt. Kontrollfragen im Text tragen entscheidend zum Rekapitulieren des Gelesenen bei. Jedes Kapitel endet mit einer Zusammenfassung und Fragen zum vermittelten Stoff. Als Ergänzung dient das ausführliche Übungsbuch mit Aufgaben und Lösungen zu den jeweiligen Kapiteln des Lehrbuches. Die 37 Kapitel machen verständlich mit den einzelnen Gebieten der Physik vertraut. KW - Physik KW - Thermodynamik PY - 2020 DO - https://doi.org/10.1002/maco.202070066 SN - 1521-4176 SN - 0947-5117 VL - 71 IS - 6 SP - 3 EP - 4 PB - WILEY‐VCH Verlag GmbH & Co. KGaA CY - Weinheim AN - OPUS4-50839 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Thöns, Sebastian A1 - Stewart, M. G. T1 - On the cost-efficiency, significance and effectiveness of terrorism risk reduction strategies for buildings N2 - We analyse the performance of risk reduction strategies for Terrorist attacks with Improvised Explosive Devices (IEDs) for large governmental building structures in terms of cost-efficiency, significance and effectiveness Accounting for life safety in conjunction with societal preferences and capabilities. The approach builds upon an extended Bayesian pre-posterior decision analysis and the principles of the marginal lifesaving costs based on the Life Quality Index (LQI). The decision scenario is formulated for a decision maker responsible for the safety of governmental or large commercial buildings and consequently the direct risks, the indirect risks due to fatalities and economical importance of the building beside the expected cost for the individual risk reduction strategies are modelled, aggregated and optimised. The considered risk reduction strategies encompass an explicit consideration and distinction of information and actions such as (i) threat surveillance may trigger the temporary evacuation of the building, (ii) the implementation of protection provisions provided by codes and guidelines, (iii) a detailed progressive collapse assessment and specific protection measures and (iv) the combination of protection and surveillance. All considered strategies are found to contribute to risk reduction and can be costefficient, especially for higher threat probabilities. The risk reduction strategies comply with societal macroeconomic and demographical characteristics and societal preferences according to the LQI. The progressive collapse assessment with targeted protection measures is found to be the most cost-efficient, significant and effective counter-terrorism strategy. This finding points to the necessity for a comprehensive utilisation of scientific methods and sophisticated engineering for progressive collapse assessment to determine targeted protection measures. KW - Significance and effectiveness KW - Risk mitigation strategies KW - Terrorist attacks KW - Value of information KW - Bayesian probability KW - Reliability KW - Risk and decision analysis KW - Decision optimality PY - 2020 DO - https://doi.org/10.1016/j.strusafe.2020.101957 VL - 85 SP - 10195 PB - Elsevier Ltd. AN - OPUS4-50794 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Weise, Frank T1 - Innenhydrophobierung - neuartige AKR-Vermeidungsstrategie N2 - Verstärkt auftretende Schäden in Betonfahrbahndecken des Bundesfernstraßennetzes, die mit einer Alkali-Kieselsäure-Reaktion (AKR) in Verbindung gebracht werden, haben zu einer massiven Verschärfung der Prüfvorschriften zur Bewertung der Alkaliempfindlichkeit von Ge-steinskörnungen geführt. Die damit verbundene Einschränkung potenziell für den Straßenbau einsetzbarer Gesteinskörnungen ruft eine verstärkte Ressourcenknappheit und ein erhöhtes Transport- und damit einhergehendes Kostenaufkommen hervor. Vor diesem Hintergrund wird nach neuartigen AKR-Vermeidungsstrategien gesucht, die auch eine Verwendung grenzwertig alkaliempfindlich eingestufter Gesteinskörnungen erlaubt. Einen möglichen Lösungsansatz stellt in diesem Kontext die Innenhydrophobierung des Fahrbahndeckenbetons dar. Es soll so durch die Behinderung des Feuchte- und Tausalzeintrags in den Beton der AKR-Schädigungs-prozess signifikant vermindert werden. Für die Bewertung der Leistungsfähigkeit der Innen-hydrophobierung zur Vermeidung einer schädigenden AKR in Betonfahrbahndecken wird zur-zeit im Auftrage der BASt an der BAM ein Forschungsvorhaben bearbeitet. Im Rahmen dieses Beitrags werden erste ausgewählte Ergebnisse dieses Forschungsvorhabens vorgestellt. So wird exemplarisch an einem Oberbeton (0/8) mit einer alkaliempfindlichen Gesteinskörnung der Einfluss eines Hydrophobierungsmittels auf die Frisch- und Festbetoneigenschaften ganzheitlich aufgezeigt und bewertet. Bei Letzteren stehen zunächst die mechanischen und hygrischen Parameter sowie der Frost-Tausalzwiderstand im Vordergrund. In einem weiteren Schritt wird der Einfluss der Innenhydrophobierung auf die schädigende AKR mittels verschiedenartiger AKR-Performanceprüfungen beleuchtet. T2 - Betonstraßentagung 2019 CY - Aschaffenburg, Germany DA - 26.09.2019 KW - Alkali-Kieselsäure Reaktion KW - AKR KW - Innenhydrophobierung PY - 2019 AN - OPUS4-49475 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - von Werder, Julia A1 - Gardei, André A1 - Meng, Birgit ED - Caprai, V. ED - Brouwers, H. J. H. T1 - Functionalization of fibres for cement-based materials - selected test methods N2 - The low tensile strength of cement-based materials can be improved by the addition of fibres. In a joint research project, an industrial partner designed special coatings for polymer and carbon fibres by integrating surfactants and hydrophilic compounds. Aim of the developed functionalization was to ensure an even coverage of the fibre surfaces and to anchor them chemically in the cement-based matrix. Task of the BAM was to quantify the effect of the improved bond. In a first step a workable mortar adjusted to the strength of the tested fibres was developed and the fibre distribution assessed by light microscopy and computed tomography. To test the new coating for its efficiency to prevent cracking during hardening and to improve the loadbearing behaviour new test setups were developed or existing methods were adjusted. The experiments showed that the functionalization leads to a reduction of the crack area measured after the exposure of the wet mortar to strong drying conditions in the wind channel. Regarding the Efficiency to mitigate shrinkage cracks the functionalisation turned out to be more efficient for fibres made from polyacrylonitrile (PAN) than for carbon fibres. An improvement of the tensile strength after cracking of the cementitious matrix could only be documented for the coated carbon fibres. It could be quantified, however, only in the three-point bending tests because the fibres turned out to be too brittle for the applied single fibre pull-through test. T2 - 2nd International Conference on Sustainable Building Materials CY - Eindhoven, Netherlands DA - 12.08.2019 KW - Fibres KW - Functionalization KW - Mortar KW - Computed tomography KW - Shrinkage PY - 2019 VL - 5 SP - 16 EP - 25 AN - OPUS4-49480 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Babutzka, Martin T1 - Offshore-Windenergieanlagen – Ist ein dauerhafter und gleichzeitig “sauberer” Korrosionsschutz möglich? N2 - Der Vortrag verdeutlicht am Beispiel von Offshore-Windenergieanlagen, welchen Beitrag ein geeigneter Korrosionsschutz zu Fragen der Wirtschaftlichkeit, der Gesundheitstechnik und der Sicherheit leistet. Die Umweltverträglichkeit von Korrosionsschutzmaßnahmen wird anhand der Emission von chemischen Substanzen und Verbindungen beleuchtet. T2 - 29. Berliner Gesundheitstechnische Tagung - 70 Jahre Gesundheitstechnische Gesellschaft CY - Berlin, Germany DA - 08.11.2019 KW - Offhsore-Windenergieanlagen KW - Umweltverträglichkeit KW - Korrosion KW - Korrosionsschutz PY - 2019 AN - OPUS4-49560 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Nerger, Deborah T1 - Post-impact evaluation at RC plates with planar tomography and FEM N2 - The aim of the work is to develop experimental investigation strategies to determine damage quantities and the liquid Intrusion behaviour of containment structures in case of aircraft collision. T2 - 36th Danubia Adria Symposium on Advances in Experimental Mechanics CY - Pilsen, Czech Republik DA - 24.09.2019 KW - Impact KW - Damage characterization KW - Planar tomography KW - Numeric simulation KW - Reinforced concrete structure PY - 2019 AN - OPUS4-49542 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Burkert, Andreas T1 - Korrosionsmonitoring bei der Instandsetzung von chloridbelasteten Stahlbetonwerken N2 - In der aktuellen RL-SIB wie auch im Gelbdruck der Instandhaltungsrichtlinie ist bei Anwendung des Instandsetzungsprinzips W-Cl bzw. Verfahren 8.3 der Erfolg der Maßnahme durch Einbau und Messung von Korrosionsstrom-Mess-Einrichtungen nachzuweisen. Auch wird bei der Instandsetzung von chloridbelasteten Rissen bei Stahlbetonbauteilen durch Verpressen der Risse bzw. Aufbringen einer Rissbandage ein Korrosionsmonitoring empfohlen. Anerkannte Regelwerke oder Normen über Art und Aufbau des Monitoring-Systems sowie Kriterien zur Bewertung der Messergebnisse im Hinblick auf den Erfolg der Instandsetzungsmaßnahme gibt es derzeit nicht. Auch sind keine Untersuchungen zur Qualität der Messergebnisse veröffentlicht. Ziel des Vorhabens ist die Ausarbeitung eines Regelwerks-Entwurfes für die Art und den Aufbau von Korrosionsmonitoring-Systemen sowie für Kriterien zur zuverlässigen Bewertung der Messergebnisse, mit denen der Erfolg bei verschiedenen Instandsetzungskonzepten überprüft werden kann. T2 - 13. Sitzung des NA 062 01 77 AA „Korrosionsprüfverfahren“ CY - Neuss, Germany DA - 24.10.2019 KW - Korrosion KW - Monitoring KW - Sensoren KW - Chloridbelastete Stahlbetonbauwerke PY - 2019 AN - OPUS4-49462 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schartel, Bernhard T1 - Flammschutz für technische Kunststoffte für elektronische Anwendungen N2 - Das Brandverhalten stellt wie das ausgezeichnete elektrische Isolationsverhalten, die geringen elektrischen Verluste, die Verarbeitbarkeit und Formbarkeit eine der wesentlichen Schlüsseleigenschaften im Eigenschaftsprofil von Polymerwerkstoffen in der Elektronik und der Elektrotechnik dar. Dabei bedarf es einer Ausrüstung der Polymerwerkstoffe mit Flammschutzmittel. Die Entwicklung von immer effizienteren, synergistischen und multifunktionalen Multikomponentensystemen ist dabei eine herausragende Quelle für Innovation. Die Entwicklung und Verbesserung der werkstoff- und anwendungsspezifischen Flammschutzlösungen bestimmen die aktuellen und zukünftigen Polymermaterialien in der Elektronik und Elektrotechnik mit. Der Vortrag stellt anhand von Beispielen einige der erfolgreichen Konzepte dar. Es wird versucht, über das wissenschaftlich-systematische Verständnis Grundprinzipien und vielversprechende Lösungsstrategien zu verdeutlichen. T2 - Kunststoff trifft Elektronik, KUZ Kunststoffzentrum in Leipzig CY - Leipzig, Germany DA - 29.01.2020 KW - Flame retardant KW - Ssynergy KW - Flame retardant mode of action KW - UL 94 KW - Cone calorimeter PY - 2020 AN - OPUS4-50495 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rai, Alena T1 - Volumetrische Ansprache von Grindingoberflächen N2 - Seit einigen Jahren steht die Oberflächentexturierung der Betonfahrbahndecken mittels Grinding im Fokus der Forschung und Entwicklung des Betonstraßenbaus. Dabei wird das Ziel verfolgt, Grindingtechnologie zeitnah in das deutsche Regelwerk einzuführen und gegebenenfalls die Regelbauweise Waschbeton dadurch zu ersetzen. Im Rahmen der systematischen Erprobung konnte festgestellt werden, dass es, bedingt durch Beanspruchungen während der Nutzungsphase, zur Verbesserung bzw. Verschlechterung der relevanten Oberflächenperformances, wie z.B. Griffigkeit, Ebenheit oder Geräuschpegel kommt. Dies wird gegenwärtig mit den Texturgeometrieveränderungen in Verbindung gebracht. Vor diesem Hintergrund stellt sich zunächst die Frage, in wie weit die Grindingtextur und deren Veränderungen messtechnisch erfasst werden können und welche statistischen Kenngrößen dabei abgeleitet werden können. In diesem Zusammenhang ist eine Evaluation der dreidimensionalen messtechnischen Ansprache von Grindingoberflächen notwendig. Perspektivisch bedarf es einer Korrelationsanalyse zwischen der o.g. Texturkenngrößen mit Veränderungen der Oberflächenperformances. Dieser Beitrag zeigt, dass mithilfe eines auf Streifenlichtprojektion basierenden Messsystems, eine hochaufgelöste volumetrische Erfassung der Oberflächentopografie verschiedener Grindingtexturen sowohl im Labor als auch in situ möglich ist. Darauf aufbauend galt es, die messtechnischen Voraussetzungen zur Gewährleistung reproduzierbarer Messungen zu schaffen. Dies ermöglicht eine Dokumentation der zeitlichen Texturveränderungen infolge verschieden-artiger Beanspruchungen. Basierend auf den Ergebnissen der 3D-Texturerfassung wurden Auswerteroutinen zur quantitativen und statistischen Charakterisierung der Oberflächentextur entwickelt. Zusätzlich wurden diese angewandt, um exemplarisch die Veränderungen der Oberflächentopographie infolge klimatischer Beanspruchung quantitativ abzubilden. T2 - Workshop Grinding CY - Bergisch Gladbach, Germany DA - 28.01.2020 KW - Betonfahrbahndeckentexturen KW - Grinding KW - 3D-Texturerfassung KW - Streifenlichtprojektionssystem PY - 2020 AN - OPUS4-50449 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Viefhues, Eva T1 - Subspace-based damage detection handling temperature effects and uncertainty in the reference N2 - Temperature variation can be a nuisance that perturbs vibration based structural health monitoring (SHM)approaches for civil engineering structures. In this paper, temperature affected vibration data is evaluated within a stochastic damage detection framework, which relies on a null space based residual. Besides two existing temperature rejection approaches – building a reference state from an averaging method or a piecewise method – a new approach is proposed, using model interpolation. In this approach, a general reference model is obtained from data in the reference state at several known reference temperatures. Then, for a particular tested temperature, a local reference model is derived from the general reference model. Thus, a well fitting reference null space for the formulation of a residual is available when new data is tested for damage detection at an arbitrary temperature. Particular attention is paid to the computation of the residual covariance, taking into account the uncertainty related to the null space matrix estimate. This improves the test performance, contrary to prior methods, for local and global damages, resulting in a higher probability of detection (PoD) for the new interpolation approach compared to previous approaches. T2 - Abteilungs-Vortragsseminar Abteilung 7 Bauwerksicherheit CY - Berlin, Germany DA - 28.11.2019 KW - Statistical method KW - Subspace-based method KW - Temperature rejection KW - Model interpolation KW - Uncertainty PY - 2019 AN - OPUS4-50195 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz T1 - Zur Berechnung der Erschütterungsminderung von Eisenbahngleisen mit ein- und zweidimensionalen Modellen N2 - Eindimensionale Modelle des Gleises aus einem Schienenstützpunkt, zweidimensionale Modelle enthalten die Kraftverteilung der Schiene. Eindimensionale Modelle machen einen Fehler, weil sie eine zu große Fahrzeugmasse berücksichtigen. Man kann jedoch bei der Berechnung der Minderungswirkung von Gleiselementen eindimensionale Gleismodelle verwenden, um die Kraftübertragung des Gleises bzw. die Minderungswirkung des Gleises zu berechnen. Die Wechselwirkung mit dem Fahrzeug kann einfach mit der dynamischen Stützpunktsteifigkeit berechnet werden. Dabei muss die Stützpunktsteifigkeit mit einer charakteristischen Gleislänge multipliziert werden, die frequenz- und systemabhängig ist. T2 - Norm-Arbeitsausschuss Schwingungsminderung in der Umgebung von Verkehrswegen CY - Munich, Germany DA - 14.01.2020 KW - Richtige Fahrzeugmasse KW - Erschütterungsminderung KW - Elastische Gleiselemente KW - Rechenverfahren PY - 2020 AN - OPUS4-50268 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CHAP A1 - Schartel, Bernhard A1 - Kebelmann, Katharina ED - Hu, Y. ED - Wang, X. T1 - Fire testing for the development of flame retardant polymeric materials N2 - Flame retarded polymeric materials are used in various applications in which a certain fire behavior is demanded. Protection goals are defined, such as limited flammability in terms of hindered sustained ignition or limited contribution to a fire, and these protection levels are tested with defined specimens or components in defined fire scenarios, that is to say, different fire tests. Passing a specific fire test by meeting whatever its demands is often the most important development goal, so the parameters of the different fire tests vary widely to emphasize different fire properties. Some fire tests are used to screen or provide a general assessment of flame retardant polymers during development, while other fire tests and tailored experiments are performed to address special phenomena or understand the flame retardancy modes of action. For all fire testing, the devil is in the details – demanding know-how and crucial efforts to manage the quality of investigations and advanced interpretation. This chapter aims to offer a structured overview of all these aspects. KW - Fire testing KW - Flame retardant KW - Fire retardant KW - Flammability KW - Ignition KW - Oxygen index KW - Cone calorimeter KW - UL 94 KW - Developing fire KW - Uncertainty KW - Fire resistance PY - 2020 SN - 978-1-138-29578-7 SP - 35 EP - 55 PB - CRC Press AN - OPUS4-50236 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Battig, Alexander A1 - Markwart, J. C. A1 - Wurm, F. R. A1 - Schartel, Bernhard T1 - Sulfur's role in the flame retardancy of thio-ether–linked hyperbranched polyphosphoesters in epoxy resins N2 - Hyperbranched polyphosphoesters are promising multifunctional flame retardants for epoxy resins. These polymers were prepared via thiol-ene polyaddition reactions. While key chemical transformations and modes of actions were elucidated, the role of sulfur in the chemical composition remains an open question. In this study, the FR-performance of a series of phosphorus-based flame retardant additives with and without sulfur (thioethers or sulfones) in their structure are compared. The successful synthesis of thio-ether or sulfone-containing variants is described and verified by 1H and 31P NMR, also FTIR and MALDI-TOF. A decomposition process is proposed from pyrolytic evolved gas analysis (TG-FTIR, Py-GC/MS), and flame retardancy effect on epoxy resins is investigated under pyrolytic conditions and via fire testing in the cone calorimeter. The presence of sulfur increased thermal stability of the flame retardants and introduced added condensed phase action. Likely, Sulfur radical generation plays a key role in the flame-retardant mode of action, and sulfones released incombustible SO2. The results highlight the multifunctionality of the hyperbranched polymer, which displays better fire performance than its low molar mass thio-ether analogue due to the presence of vinyl groups and higher stability than its monomer due to the presence of thio-ether groups. KW - Phosphoester KW - Hyperbranched KW - Sulfur KW - Thio-ether KW - Flame retardant KW - Epoxy resin PY - 2020 DO - https://doi.org/10.1016/j.eurpolymj.2019.109390 SN - 0014-3057 VL - 122 SP - 109390 PB - Elsevier Ltd. AN - OPUS4-50238 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Turski Silva Diniz, Analice A1 - Huth, Christian A1 - Schartel, Bernhard T1 - Dripping and decomposition under fire: Melamine cyanurate vs. glass fibres in polyamide 6 N2 - Manipulating the melt dripping of thermoplastics makes a fire scenario more or less dangerous. Yet, a detailed understanding of this phenomenon has remained a question mark in studies of the flammability of plastics. In this work, the individual and collective impacts of additives on the dripping behaviour of polyamide 6 (PA6) were studied. A set of materials compounded with melamine cyanurate (MCA) and glass fibre (GF) was investigated. Under UL 94 vertical test conditions, the dripping during first and second ignition was quantified and investigated in detail. The number, size and temperature of the drops were addressed, and the materials and their drops evaluated with respect to such aspects as their averaged molecular weight, thermal decomposition and rheological properties. PA6 with V-2 classification improved to V-0 with the addition of MCA, and achieved HB in the presence of GF. PA6/GF/MCA achieved V-2. Non-flaming drops of PA6/MCA consisted of oligomeric fragments. Flaming drops of PA6/GF showed a more pronounced decomposition of PA6 and an increased GF content. The dripping behaviour of PA6/GF/MCA can be understood as a combination of the influence of both additives. The results showed nicely that dripping under fire is neither a straightforward material property nor a simple additive influence, but the complex response of the material influenced by the interaction and competition of different phenomena. KW - Dripping KW - UL 94 KW - Polyamide 6 KW - Melamine cyanurate KW - Glass fibre KW - Flame retardant PY - 2020 DO - https://doi.org/10.1016/j.polymdegradstab.2019.109048 SN - 0141-3910 VL - 171 SP - 109048 PB - Elsevier Ltd. AN - OPUS4-50239 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Zirnstein, Benjamin A1 - Schulze, Dietmar A1 - Schartel, Bernhard T1 - Combination of phosphorous flame retardants and aluminum trihydrate in multicomponent EPDM composites N2 - Ethylene propylene diene monomer (EPDM) Rubbers with the flame retardants tris(2-ethylhexyl)phosphate, ammonium polyphosphate, polyaniline, and aluminum trihydroxide were prepared and analyzed in this study. The homogenous dispersion of the fillers in the rubber matrix was confirmed by scanning electron microscope. To investigate the interplay of the different flame retardants, the flame retardants were varied systematically. The comprehensive study sought combinations of flame retardants that allow high loadings of flame retardants without deterioration of the physical and mechanical properties of the EPDM rubber. The eight EPDM rubbers were investigated via thermogravimetric analysis and pyrolysis gas chromatography coupled with a mass spectrometer (Py GC/MS) to investigate the potential synergistic effects. In the Py-GC/MS experiments, 27 pyrolysis products were identified. Furthermore, UL 94, limiting oxygen index, FMVSS 302, glow wire tests, and cone calorimeter tests were carried out. In the cone calorimeter test the EPDM rubbers R-1AP and R-1/2P achieved an increase in residue at flameout of 76% and a reduction in total heat evolved of about 35%. Furthermore, the compounds R-1AP and R-1/2P achieved a reduction in MARHE to about 150 kW m−1, a reduction of over 50% compared to the unprotected rubber R. KW - EPDM KW - Rubber KW - Aluminum hydroxide (ATH) KW - Phosphorous flame retardant PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-502859 DO - https://doi.org/10.1002/pen.25280 SN - 1548-2634 VL - 60 IS - 2 SP - 267 EP - 280 PB - Wiley AN - OPUS4-50285 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Auersch, Lutz T1 - Characteristics of train passages over slab tracks from measurements and different track-soil models - Damage detection and ground vibration reduction N2 - The train passages over intact or damaged slab tracks on different soils have been calculated by the finite-element boundary-element or the wavenumber-domain method. The influence of track and soil parameters on the distribution of the track displacements and the soil forces has been analysed. The measured and calculated displacement time histories of train passages could be used to identify track damages such as lose sleepers or a lose track plate. The time histories and spectra of the soil forces can explain the measured ground vibration reduction of slab tracks. The calculated displacement and force distributions of slab tracks on continuous soils do not fulfil the Winkler hypothesis and Winkler models should not be used for track analysis. KW - Wavenumber domain KW - Continuous soil KW - Slab track KW - Soil forces KW - Track displacements KW - Track filter KW - Vehicle–track interaction PY - 2020 DO - https://doi.org/10.1177/0954409719835036 SN - 0954-4097 VL - 234 IS - 2 SP - 142 EP - 160 PB - Sage CY - London AN - OPUS4-50266 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - THES A1 - Hauswaldt, Sebastian T1 - Kontinuumsmechanische Werkstoffmodelle zur numerischen Simulation von Stahlbauteilen im Brandfall N2 - Das nichtlineare und geschwindigkeitsabhängige Materialverhalten von Stahl wird besonders bei hohen Temperaturen sichtbar. Für Finite-Elemente-Simulationen von Stahlkonstruktionen im Brandfall sollte aus diesem Grund plastisches und geschwindigkeitsabhängiges Materialverhalten beschrieben werden. Die vorliegende Arbeit betrachtet unter diesem Aspekt bisherige Materialuntersuchungen und macht Vorschläge für dreidimensionale Materialmodelle mit entsprechenden Eigenschaften. Es werden zunächst die phänomenologischen Eigenschaften von Baustahl anhand einer Literaturrecherche analysiert, wobei verstärkt auf Untersuchungen des Materialverhaltens bei Belastungen und Aufheizprozessen, wie sie im Brandfall zu erwarten sind, geachtet wird. Die für die Bemessung von Stahlkonstruktionen gebräuchliche Spannungsbeschreibung des EC 3-1-2 wird untersucht. Es werden ihre Stärken, aber auch die zur Entwicklung einer kontinuumsmechanischen Materialformulierung fehlenden Eigenschaften, aufgezeigt. Ein nichtlinear-elastisches kontinuumsmechanisches Materialmodell der Deformationstheorie der Plastizität wird so angepasst, dass es die Spannungs-Dehnungslinien gemäß EC 3-1-2 im einachsigen Spannungszustand beschreibt. Es wird des Weiteren ein thermoelastisch-viskoplastisches Modell vorgestellt, das in der Lage ist, Kriechen und Relaxation bei Aufheiz- und Abkühlprozessen zu beschreiben. Die Struktur dieses Materialmodells wird so gewählt, dass die Parameter an hierfür geeigneten Messergebnissen leicht identifiziert werden können. Der deviatorische Anteil des Modells besteht aus einem geschwindigkeitsunabhängigen, plastischen Anteil und einem geschwindigkeitsabhängigen, viskoelastischen Anteil. Der geschwindigkeitsunabhängige, plastische Anteil wurde als Differentialgleichung auf Grundlage der so genannten endochronen Plastizitätstheorie formuliert. Die Parameter der Materialmodelle werden auf Grundlage der Messergebnisse stationärer Warmzugversuche an Baustahlproben identifiziert. Sowohl das nichtlinear-elastische EC 3-1-2-Materialmodell als auch das thermoelastisch-viskoplastische Materialmodell mit den an Baustahl angepassten Materialparametern wird numerisch für die Verwendung mit Finite-Elemente-Programmen aufbereitet und als UMAT-Subroutine für ABAQUS in der Programmiersprache FORTRAN implementiert. Hierbei wird insbesondere auf die Bereitstellung der konsistenten Tangentenoperatoren Wert gelegt, um eine effiziente numerische Berechnung bei Verwendung der Materialmodelle zu ermöglichen. Abschließend werden erste Simulationsrechnungen vorgestellt, um beispielhaft die Möglichkeiten der Anwendung der entwickelten und implementierten Materialmodelle für Simulationen von Stahlkonstruktionen im Brandfall aufzuzeigen. N2 - The non-linear and rate-dependent material behaviour of steel becomes particularly visible at high temperatures. For finite-element-simulations of steel structures in the event of fire, plastic and rate- dependent material behaviour should therefore be described. With this in mind, this thesis looks at previous material investigations and makes suggestions for three-dimensional material models with the corresponding properties. The phenomenological properties of structural steel are analysed on the basis of a literature study, whereby increased attention is paid to the material behaviour under loads and heating processes, as can be expected in the event of fire. The stress-strain-relation of the EC 3-1-2 used for the design of steel structures is examined. The advantages of this description, but also the missing properties for the development of a continuum-mechanical material formulation, are shown. A non-linear-elastic continuum mechanical material model of the deformation theory of plasticity is adapted in such a way that it describes the stress-strain curves according to EC 3-1-2 in the state of uniaxial stress. Furthermore, a thermoelastic-viscoplastic model is presented which is able to describe creep and relaxation during heating and cooling processes. The structure of this material model is chosen in such a way that the parameters can be easily identified using certain measurement results. The deviatoric part of the model consists of a rate-independent, plastic part and a rate-dependent, vis- coelastic part. The rate-independent, plastic part was formulated as a differential equation based on the endochronic theory of plasticity. The parameters of this material model are identified on the basis of the measurement results of stationary hot tensile tests on structural steel specimens. Both the non-linear-elastic EC 3-1-2 material model and the thermoelastic-viscoplastic material model with the material parameters adapted to mild steel are prepared numerically for use with finite- element-programs and implemented as UMAT-subroutines for ABAQUS in the FORTRAN code. Particular emphasis is placed on the provision of consistent tangent operators to enable efficient numerical calculation when using the material models. Finally, first finite-element-simulations are presented in order to show the possibilities of the developed and implemented material models for simulations of steel constructions in case of fire. T3 - BAM Dissertationsreihe - 167 KW - Brandschutz KW - Stahl KW - Brandverhalten KW - Finite-Elemente-Methode KW - Materialmodell KW - Eurocode 3-1-2 KW - UMAT KW - Fire prevention KW - Steel KW - Fire behaviour KW - Finite element method KW - Material model KW - Eurocode 3-1-2 KW - UMAT PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-507662 SN - 1613-4249 VL - 167 SP - i EP - 206 PB - Bundesanstalt für Materailforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-50766 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hothan, Sascha T1 - Reaktive Brandschutzsysteme für Stahlbauteile N2 - Die Erkenntnisse zu reaktiven Brandschutzsystemen (RBS) werden kontinuierlich erweitert, was sich in der Entwicklung neuer Produkte und der Ausweitung des durch technische Regelungen abgedeckten Anwendungsbereichs äußert. Der hier vorliegende Beitrag konzentriert sich auf die Verwendung von RBS auf Stahlkonstruktionen. In den vergangenen zehn Jahren wurden, abgesichert durch neue Erkenntnisse aus der Forschung, die Anwendung auf Stahlzuggliedern mit offenem Profil präzisiert und im Rahmen allgemeiner bauaufsichtlicher Zulassungen (abZ) neu geregelt. Ferner wurde die Grundlage geschaffen, die Anwendung von RBS auf Zuggliedern mit kreisrundem Vollprofil zu bewerten und auf Basis der abZ zu ermöglichen. Neben einer umfassenden Darstellung der aktuellen nationalen und europäischen Regelungen zu RBS, werden technologische Besonderheiten und deren Einfluss auf den Regelungsinhalt im Beitrag thematisiert. In der jüngsten Vergangenheit stellt sich mit zunehmender Dringlichkeit die Frage nach der Bewertung der Dauerhaftigkeit von RBS für lange Zeiträume, wobei damit Nutzungsdauern weit jenseits der in den nationalen und europäischen Regelungen bereits etablierten 10 Jahre gemeint sind. In diesem Zusammenhang ist zu klären, wie der Feuerwiderstand von Konstruktionen zu bewerten ist, die bereits über lange Zeiträume mit RBS versehen sind. T2 - Fortbildungsseminar "Vorbeugender Brandschutz” an der Hessischen Landesfeuerwehrschule Kassel CY - Kassel, Germany DA - 04.12.2019 KW - Brandschutz KW - Stahl KW - Reaktive Brandschutzsysteme PY - 2019 AN - OPUS4-50672 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schartel, Bernhard A1 - Günther, Martin T1 - Flame retardancy of polyurethanes N2 - Polyurethanes (PU) represent one of the most versatile classes of plastics. They are processed and used as thermoplastic, elastomer, and thermoset. The requirements regarding flammability are correspondingly versatile. Depending on the material and the field of application, specific fire tests have to be fulfilled. This paper describes the different concepts used to fulfil these requirements by choosing the right raw materials and flame retardants. KW - Polyurethane KW - Flame retardant KW - Foam KW - Flammability KW - Pyrolysis KW - Cone calorimeter PY - 2020 VL - 17 IS - 1 SP - 44 EP - 48 PB - Dr. Gupta AN - OPUS4-50737 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CHAP A1 - Rabe, Sebastian A1 - Sanchez-Olivares, G. A1 - Pérez-Chávez, R. A1 - Schartel, Bernhard ED - Laoutid, F. T1 - Natural Keratin and Coconut Fibres from Industrial Wastes in Flame Retarded Thermoplastic Starch Biocomposites N2 - Natural keratin fibres derived from Mexican tannery waste and coconut fibres from coconut processing waste were used as fillers in commercially available, biodegradable thermoplastic starch-polyester blend to obtain sustainable biocomposites. The morphology, rheological and mechanical properties as well as pyrolysis, flammability and forced flaming combustion behaviour of those biocomposites were investigated. In order to open up new application areas for these Kinds of biocomposites, ammonium polyphosphate (APP) was added as a flame retardant. Extensive flammability and cone calorimeter studies revealed a good flame retardance effect with natural fibres alone and improved effectiveness with the addition of APP. In fact, it was shown that replacing 20 of 30 wt. % of APP with keratin fibres achieved the same effectiveness. In the case of coconut fibres, a synergistic effect led to an even lower heat release rate and total heat evolved due to reinforced char residue. This was confirmed via scanning electron microscopy of the char structure. All in all, these results constitute a good approach towards sustainable and biodegradable fibre reinforced biocomposites with improved flame retardant properties. KW - Biomaterials KW - Biodegradation KW - Calorimetry KW - Composites KW - Flame retardance PY - 2020 SN - 978-3-03928-350-7 SN - 978-3-03928-351-4 SP - 45 EP - 66 PB - MDPI AN - OPUS4-50738 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Rabe, Sebastian A1 - Klack, Patrick A1 - Bahr, Horst A1 - Schartel, Bernhard T1 - Assessing the fire behavior of woods modified by N-methylol crosslinking, thermal treatment, and acetylation N2 - Wood products are often treated by different techniques to improve their longevity when used as building materials. Most of the time, the goal is to increase their resistance to weathering effects, deformations in material dimensions or biotic decomposition. These wood treatment techniques have a significant impact on pyrolysis and burning behavior. The general effects of three different common wood treatments on flame retardancy were investigated by comparing treated woods with their untreated counterparts and with other kinds of wood. While the acetylation of beech leads to a slightly increased fire hazard, the thermal treatment of wood and crosslinking of cellulose microfibrils dimethyloldihydroxy-ethyleneurea show a limited flame retarding effect. Switching to woods with a higher lignin content, and thus higher char yield, however, results in a more pronounced improvement in flame retardancy performance. This article delivers a comprehensive and balanced assessment of the general impact of different wood modifications on the fire behavior. Further, it is a valuable benchmark for assessing the flame retardancy effect of other wood modifications. KW - Acetylation KW - Cone claorimeter KW - DMDHEU KW - Heat of combustion KW - Thermal treatment KW - Wood modification PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-507397 DO - https://doi.org/10.1002/fam.2809 SN - 1099-1018 SN - 0308-0501 VL - 44 IS - 4 SP - 530 EP - 539 PB - Wiley Online Libary AN - OPUS4-50739 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Ma, S. A1 - Xiao, Y. A1 - Zhou, F. A1 - Schartel, Bernhard A1 - Chan, Yin Yam A1 - Korobeinichev, O. P. A1 - Trubachev, S. A. A1 - Hu, W. A1 - Ma, C. A1 - Hu, Y. T1 - Effects of novel phosphorus-nitrogen-containing DOPO derivative salts on mechanical properties, thermal stability and flame retardancy of flexible polyurethane foam N2 - In this work, a series of 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO) derivative salts containing phosphorus and nitrogen were synthesized, and their effects on mechanical properties, thermal stability and flame retardancy of flexible polyurethane foam (FPUF) were investigated. Studies have shown that the addition of DOPO derivatives will increase the tensile strength, compression set, and compression hardness of FPUF, but it will lead to a decrease in elongation at break. Thermogravimetric analysis showed that the initial decomposition temperature of FPUF containing DOPO derivatives was reduecd, but the char reside was significantly improved. A series of combustion tests indicated that the addition of DOPO derivative salts can improve the flame retardancy of FPUF, of which 10-hydroxy-9,10-dihydro-9-oxa-10 phosphaphenanthrene-10-oxide dicyandiamide salt (D-DICY) exhibited the best flame retardancy. When the load of D-DICY was 20 phr, the limiting oxygen index (LOI) of foam reached 24.5%, and the peak heat release rate and total heat release were decreased by 55.7% and 52.9%, respectively. Furthermore, based on the analysis of the gas phase combustion products and the char residue of the condensed phase, the possible flame retardant mechanism was proposed. KW - Flexible polyurethane foam KW - DOPO derivative salts KW - Mechanical properties KW - Thermal stability KW - Flame retardancy PY - 2020 DO - https://doi.org/10.1016/j.polymdegradstab.2020.109160 SN - 0141-3910 VL - 177 SP - 109160 PB - Elsevier Ltd. AN - OPUS4-50740 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz T1 - Das Prognosetool der BAM zur Emission, Transmission und Immission von Bahnerschütterungen N2 - Die gesamte Prognose wurde rechnerisch erfasst. Die Rechenverfahren sind einfach und schnell. Die Emission und die Immission verwendet Übertragungsmatrizen. Die Transmissionsrechnung beruht auf der Dispersion der Rayleighwelle. Die Verknüpfung erfolgt über die Anregungskraft auf den Boden und über die Freifeldamplitude am Gebäude. Es sind viele Eingabemöglichkeiten für Messdaten vorgesehen. Messungen können von einem Ort auf einen anderen Ort übertragen werden. T2 - 98. Sitzung des Normausschusses "Schwingungsminderung in der Umgebung von Verkehrswegen" CY - Online meeting DA - 07.05.2020 KW - Bahnerschütterungen KW - Prognose KW - Übertragungsmatrizen KW - Rayleighwellendispersion PY - 2020 AN - OPUS4-50748 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schartel, Bernhard A1 - Günther, Martin T1 - Flammschutz von Polyurethanen N2 - Polyurethane (PU) bilden eine der vielseitigsten Klassen der Polymerwerkstoffe. Kein anderer Kunststoff wird sowohl als Thermoplast, als Elastomer wie auch als Duroplast verarbeitet und eingesetzt. Entsprechend vielfältig sind auch die Anforderungen an den Flammschutz. Je nach Material und Anwendung müssen spezifische Brandnormen erfüllt werden. Der vorliegende Aufsatz gibt einen Überblick über die verfügbaren Ansätze, um durch geeignete Auswahl der Rohstoffe und der Flammschutzmittel diese verschiedensten Anforderungen an das Brandverhalten zu erfüllen. KW - Polyurethan KW - Flammschutz KW - Pyrolyse KW - Schaum KW - Cone calorimeter PY - 2020 VL - 20 IS - 1 SP - 48 EP - 53 PB - Dr. Gupta AN - OPUS4-50736 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hu, W.-H. A1 - Xu, Z.-M. A1 - Liu, M.-Y. A1 - Tang, D.-H. A1 - Lu, W. A1 - Li, Z.-H. A1 - Teng, J. A1 - Han, X.-H. A1 - Said, Samir A1 - Rohrmann, R. G. T1 - Estimation of the Lateral Dynamic Displacement of High-Rise Buildings underWind Load Based on Fusion of a Remote Sensing Vibrometer and an Inclinometer N2 - This paper proposes a novel method to estimate the lateral displacement of high-rise structures under wind loads. The coefficient β(x) is firstly derived, reflecting the relation between the structural lateral dynamic displacement and the inclination angle at the height x of a structure. If the angle is small, it is the ratio between the structural fundamental mode shape and its first-order derivative without influence of external loads. Several dynamic experiments of structures are performed based on a laser remote sensing vibrometer and an inclinometer, which shows that the fundamental mode is dominated in the structural displacement response under different types of excitations. Once the coefficient β(x) is curve-fitted by measuring both the structural lateral dynamic displacement and the inclination angle synchronously, the real-time structural lateral displacement under operational conditions is estimated by multiplying the coefficient β(x) with the inclination angle. The advantage of the proposed method is that the coefficient β(x) can be identified by lateral dynamic displacement measured in high resolution by the remote sensing vibrometer, which is useful to reconstruct the displacement accurately by the inclination angle under operational conditions KW - Inclination angle KW - High-rise building KW - Lateral dynamic displacement KW - Remote sensing vibrometer PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-506833 DO - https://doi.org/10.3390/rs12071120 VL - 12 IS - 7 SP - 1120 PB - MDPI CY - 4052 Basel, Schweiz AN - OPUS4-50683 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Wagner, Adrian T1 - Ergebnisse der 1. Probenentnahme im rahmen des Forschungsprojekt es zur Auslagerung von Edel und Duplexstählen in Straßentunneln N2 - Aufgrund der stark korrosiven Atmosphäre in Tunnelbauwerken kommt es aufgrund von Reinigungs- und Sanierungsmaßnahmen an Ein- und Anbauteilen aus nichtrostendem Stahl häufig zu wartungsbedingten Verkehrsbeeinflussungen und Tunnelsperrungen. Bislang ist nur eine kleine Gruppe rostfreier Edelstähle für die Verwendung in Tunnelbauwerken zugelassen. Im Sinne einer mittel- bis langfristigen Reduktion von Wartungsarbeiten besteht jedoch großes Interesse, die Einsatzmöglichkeiten alternativer nichtrostender Stähle zu erhöhen. Um dies zu ermöglichen, entwickelten die Bundesanstalt für Materialforschung und -prüfung (BAM), gemeinsam mit dem Landesbetrieb Straßenbau NRW, in Zusammenarbeit mit der Informationsstelle Edelstahl Rostfrei (ISER), mit Unterstützung des Edelstahlherstellers Outokumpu und der Wilhelm Modersohn GmbH & Co. KG ein Forschungsprojekt zur Auslagerung von nichtrostenden Duplexstählen in Straßentunnel. Im Oktober 2019 beteiligte sich der Landesbetrieb Straßen, Brücken und Gewässer in Hamburg und ermöglichte die Auslagerung im Elbtunnel auszuweiten. T2 - Sitzung des ISER Ausschusses Marketing CY - Düsseldorf, Germany DA - 20.11.2019 KW - Duplex KW - Outokumpu: Stainless steel KW - Duplexstahl KW - Korrosion KW - Tunnel KW - Tunnelatmosphöre PY - 2019 AN - OPUS4-49814 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Aristia, Gabriela A1 - Le, Quynh Hoa A1 - Bäßler, Ralph T1 - Corrosion of Carbon Steel in Artificial Geothermal Brine: Influence of Carbon Dioxide at 70 °C and 150 °C N2 - This study focuses on the corrosion mechanism of carbon steel exposed to an artificial geothermal brine influenced by carbon dioxide (CO2) gas. The tested brine simulates a geothermal source in Sibayak, Indonesia, containing 1500 mg/L of Cl-, 20 mg/L of SO4 2-, and 15 mg/L of HCO3-with pH 4. To reveal the temperature effect on the corrosion behavior of carbon steel, exposure and electrochemical tests were carried out at 70 °C and 150 °C. Surface analysis of corroded specimens showed localized corrosion at both temperatures, despite the formation of corrosion products on the surface. After 7 days at 150 °C, SEM images showed the formation of an adherent, dense, and crystalline FeCO3 layer. Whereas at 70 °C, the corrosion products consisted of chukanovite (Fe2(OH)2CO3) and siderite (FeCO3), which are less dense and less protective than that at 150 °C. Control experiments under Ar-environment were used to investigate the corrosive effect of CO2. Free corrosion potential (Ecorr) and electrochemical impedance spectroscopy (EIS) confirm that at both temperatures, the corrosive effect of CO2 was more significant compared to that measured in the Ar-containing solution. In terms of temperature effect, carbon steel remained active at 70 °C, while at 150 °C, it became passive due to the FeCO3 formation. These results suggest that carbon steel is more susceptible to corrosion at the near ground surface of a geothermal well, whereas at a deeper well with a higher temperature, there is a possible risk of scaling (FeCO3 layer). A longer exposure test at 150 °C with a stagnant solution for 28 days, however, showed the unstable FeCO3 layer and therefore a deeper localized corrosion compared to that of seven-day exposed specimens. KW - Carbon steel KW - CO2 KW - Corrosion KW - Electrochemical impedance spectroscopy KW - Geothermal PY - 2019 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-498168 DO - https://doi.org/10.3390/ma12223801 SN - 1996-1944 VL - 12 IS - 22 SP - 3801-1 EP - 20 PB - MDPI CY - Basel AN - OPUS4-49816 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Metz, Christian A1 - Franz, Philipp A1 - Fischer, C. A1 - Wachtendorf, Volker A1 - Maierhofer, Christiane T1 - Active thermography for quality assurance of 3D-printed polymer structures N2 - Additively manufactured test specimens made of polyamide 12 (PA 12) by Laser Sintering as well as of acrylonitrile butadiene styrene (ABS) by Fused Layer Modelling, were characterised with active thermography directly after manufacturing and after artificial weathering. For this, two different excitation methods (flash and pulse heating) were used and compared, regarding their suitability for the detection of constructed and imprinted defects inside the test specimens. To increase the quality of the thermograms, data processing methods like thermal signal reconstruction (TSR) and Fourier Transformation after TSR were applied. To further investigate the long-term stability of the additively manufactured test specimens towards environmental stress, like UV radiation, heat, humidity, water contact and frost with active thermography, an artificial weathering test over 2000 hours (~3 months) was applied to the specimens. The monitoring of the changes in the optical properties of the weathered plastics was supplemented by spectral reflectance and UV/VIS spectroscopy. KW - Additive manufacturing KW - Polymers KW - Artificial weathering KW - Active thermography KW - UV/VIS spectroscopy PY - 2019 DO - https://doi.org/10.1080/17686733.2019.1686896 SN - 1768-6733 (Print) 2116-7176 (Online) VL - 18 IS - 1 SP - 50 EP - 72 PB - Taylor & Francis AN - OPUS4-49817 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schartel, Bernhard T1 - Flame Retardancy A Bunch of Thoughts N2 - The presentation gives an overview of actual research adtivities in the field of flame retardant polymers. Details are selected illuminating the scientific topic beyond the state of the art. Different concepts are illustrated with own results obtained in different Research projects over the last 15 years. T2 - public lecture at CIATEC CY - León, Guanajuato, México DA - 06.02.2019 KW - Flame retardant KW - Modes of action KW - Mechanisms KW - Fire testing KW - Pyrolysis KW - Calorimetry PY - 2019 AN - OPUS4-50078 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Bäßler, Ralph T1 - Rezension: Zeitstandverhalten von metallischen Werkstoffen ‐ Leitfaden zur thermisch‐mechanischen Beständigkeit von Eisen‐, Nickel‐ und Kobaltlegierungen für Konstrukteure N2 - Dieser umfangreiche Leitfaden gibt Auskunft zur thermisch‐mechanischen Beständigkeit von 199 Eisen‐, 77 Nickelbasis‐ und 23 Kobaltbasislegierungen und ist ein sehr gutes und bestimmt erweiterbares Nachschlagewerk für Konstrukteure und Praktiker, die über den Einsatz geeigneter Werkstoffe in hohen Temperaturen entscheiden müssen. KW - Korrosion KW - Stahl KW - Nickellegierung KW - Kobaltlegierung PY - 2019 DO - https://doi.org/10.1002/maco.201970126 SN - 1521-4176 SN - 0947-5117 VL - 70 IS - 12 SP - 3 PB - WILEY‐VCH Verlag GmbH & Co. KGaA CY - Weinheim AN - OPUS4-50015 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Bäßler, Ralph T1 - Review: Physical Electrochemistry – Fundamentals, Techniques, and Applications N2 - The second edition of this textbook on physical electrochemistry, written by two experienced teachers of physical chemistry, corrosion engineering and materials science and engineering, covers the current knowledge which should be transferred to students of these fields. In 20 chapters the fundamentals of electrochemistry, the most important electrochemical measurement techniques and applications of electrochemistry are covered. It can be concluded that this study fulfills its intension of “serving as a key textbook in undergraduate courses” dealing with electrochemistry and being “a reference source for graduated students, researchers and engineers” interested in this field. Teachers will find sufficient content for preparing lectures on this topic. Even self‐learning is well supported by the clear structure, presented content and provided sources for further reading. KW - Corrosion KW - Electrochemistry PY - 2019 DO - https://doi.org/10.1002/maco.201970124 SN - 1521-4176 SN - 0947-5117 VL - 70 IS - 12 SP - 2345 EP - 2346 PB - WILEY‐VCH Verlag GmbH & Co. KGaA CY - Weinheim AN - OPUS4-50017 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Battig, Alexander T1 - Hyperbranched Polymeric Flame Retardants N2 - Most synthetic polymers have a high fire load, and as a result, they require flame retardants (FRs) to ensure their safe use. Phosphorus plays an important role in flame retardancy and has the potential to replace halogenated variants, which are assumed to be harmful to the environment and health. Among phosphorus-based FRs, there exists a trend towards polymeric, high molar mass molecules with complex molecular architectures. In this project, we synthesized a novel series of so-called phosphorus-based hyperbranched polymeric FRs and investigated their use as multifunctional additives to high-performance polymers, i.e. epoxy resins. By cleverly designing the chemical structure to contain varying amounts of P-O and P-N bonds, new insight into the chemical mechanism of flame retardancy was gained, and by comparing the hyperbranched polymers to their monomeric counterparts, a greater understanding of the role of complex architecture was won. This talk aims at presenting some of these results and proposes chemical mechanisms that illustrate what role these novel hyperbranched flame retardants play in molecular firefighting. T2 - AMI Fire Resistance in Plastics 2019 CY - Cologne, Germany DA - 03.12.2019 KW - Epoxy resin KW - Flame retardant KW - Hyperbranched polymers KW - Phosphoester KW - Phosphoramidate KW - Phosphoramide KW - Phosphorodiamidate KW - Pyrolysis PY - 2019 AN - OPUS4-50034 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Daus, Lars-Hendrik T1 - Weathering-induced degradation of water based intumescent coatings N2 - Bare steel constructions are often integrated in modern buildings. Intumescent coatings are widely used to protect the steel from heating up too quickly in a case of fire. As the functionality of intumescent coatings decreases with the impact of weathering processes, it is important to understand the mechanisms of material degradation to maintain long durability. The weathering-induced degradation behavior of a water-borne intumescent coating was examined, and the weakest points of the formulation were identified by a systematic approach. Resulting from this investigation, adjustments to the formula were made, leading to improved weathering resistance. T2 - European Coatings Fire Forum CY - Madrid, Spain DA - 06.11.2019 KW - Weathering KW - Brandschutz KW - Reaktive Brandschutzsysteme KW - Intumescent Coatings KW - Aeging KW - Bewitterung PY - 2019 AN - OPUS4-50039 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - THES A1 - Berchtold, Florian T1 - Metamodel for complex scenarios in fire risk analysis of road tunnels N2 - The risk analysis of road tunnels faces a growing complexity in fire scenarios, e.g. caused by new energy carriers. Essentially, such complex scenarios involve many interactions between the tunnel users, the fire source and the safety measures. One example is the alarm of tunnel users either initiated by the perception of smoke or by the fire alarm system. To consider these interactions for the quantification of consequences, e.g. fatalities, risk analysis requires a complex model. However, the complex model can compute in practice only few discrete scenarios due to its high computational cost, whereas risk analysis generally needs the consequences of a high number of random scenarios. Metamodels can solve this contradiction. They are able to approximate the consequences of many random scenarios with low computational cost based on the consequences of few discrete scenarios computed with the complex model. The efficiency of metamodels depends on the required number of these discrete scenarios. In this sense, this dissertation proposes an efficient metamodel within an innovative methodology for risk analysis of road tunnels to allow to consider an increased complexity of scenarios. This metamodel applies the following methods or models: the projection array-based design method specifies the experimental design for the discrete scenarios; the combination of the fire model FDS and the microscopic evacuation model FDS+Evac constitutes the complex model; and moving least squares produces the response surface model. The response surface model approximates the consequences of the random scenarios and therewith introduces an uncertainty, called metamodel uncertainty, which is quantified with the prediction interval method. Additionally, stochastic individual characteristics of tunnel users in discrete scenarios computed with FDS+Evac attribute evacuation uncertainties to the consequences. An original development in this dissertation, the ’direct approach’, directly transfers the evacuation uncertainties of the discrete scenarios to any random scenario. The evaluation of the metamodel in this dissertation shows following results. Firstly, the response surface model sufficiently represents the consequences of the complex model. Secondly, the metamodel uncertainty is also essential for this representation, but the prediction interval method reveals a drawback in the risk analysis. Potential approaches to deal with this drawback are discussed. Finally, the direct approach reproduces the evacuation uncertainty of the complex model which then clearly affects the consequences of random scenarios. Therefore, the consideration of the evacuation uncertainty plays an important role for the risk analysis. Furthermore, the projection array-based design method was adapted in this dissertation with two approaches, namely the combination of the experimental designs for FDS and FDS+Evac as well as their sequential refinement. Both approaches contribute to the efficiency of the metamodel. These results lead to following conclusions. Firstly, the metamodel efficiently integrates the consequences of discrete scenarios into risk analysis and thus allows to consider an increased complexity. Secondly, the metamodel is an advancement for risk analysis not only for road tunnelsbutalsomoregeneralinfiresafetyengineering. Forthesetworeasons,themetamodel might be interesting for other methodologies for risk analysis. In addition, the metamodel is generic and is therefore widely applicable on other issues beside from risk analysis, e.g. to assess the safety of structures related to time-consuming experiments depending on multiple variables. N2 - Risikoanalysen für Straßentunnel müssen eine immer größere Komplexität in Brandszenarien berücksichtigen, beispielsweise verursacht durch neue Energieträger. Dabei hängt die Komplexität von Szenarien mit einer Vielzahl von Interaktionen zwischen den Tunnelnutzern, der Brandquelle und den Sicherheitsmaßnahmen zusammen. Zum Beispiel werden Tunnelnutzer entweder direkt durch Rauch oder durch die Brandmeldeanlage alarmiert. Um die Interaktionen bei der Berechnung der Konsequenzen, wie z.B. getötete Personen, zu berücksichtigen, benötigen Risikoanalysen komplexe Modelle. Allerdings können komplexe Modelle wegen ihres hohen Zeitaufwandes nur wenige diskrete Szenarien simulieren, wohingegen Risikoanalysen auf Konsequenzen einer Vielzahl von Zufallsszenarien basieren. Als Lösung dieses Widerspruchs kommen Metamodelle in Betracht. Sie können die Konsequenzen von vielen Zufallsszenarien innerhalb kurzer Zeit näherungsweise berechnen und verwenden dafür die Konsequenzen von wenigen mit dem komplexen Modell simulierten diskreten Szenarien. Die Effizienz von Metamodellen hängt dabei mit der nötigen Anzahl von diskreten Szenarien zusammen. Demnach wird in dieser Dissertation ein effizientes Metamodell in eine selbst erstellteMethodikzurRisikoanalysefürStraßentunnelintegriert,umdamiteinehöhereKomplexität der Szenarien einbeziehen zu können. Das Metamodell setzt sich aus folgenden Methoden und Modellen zusammen: die ’projection array-based design’-Methode definiert den Simulationsplan für die diskreten Szenarien; eine Kombination aus dem Brandmodell FDS und dem mikroskopischen Evakuierungsmodell FDS+Evac bildet das komplexe Modell; und ’moving least squares’ dient zur Erstellung des Antwortflächenmodells. DasAntwortflächenmodellberechnetnäherungsweisedieKonsequenzen der Zufallsszenarien und erzeugt dadurch eine Unsicherheit, die Metamodellunsicherheit. Sie wird mit der ’prediction interval’-Methode bestimmt. Zusätzlich verursachen individuelle Eigenschaften der Tunnelnutzer in den mit FDS+Evac simulierten diskreten Szenarien Evakuierungsunsicherheiten in den Konsequenzen. Ein in der Dissertation neu entwickelter Ansatz, der ’direkte Ansatz’, überträgt die Evakuierungsunsicherheit der diskreten Szenarien unmittelbar auf die Zufallsszenarien. Die Untersuchung des Metamodels in der Dissertation führte zu folgenden Ergebnissen. Erstens,dasAntwortflächenmodellbildetdieKonsequenzenderdiskretenSzenarienausreichend genau ab. Zweitens, dazu trägt die Metamodellunsicherheit wesentlich bei. Allerdings zeigt die ’prediction-interval’-Methode einen Nachteil für die Risikoanalyse. Zur Lösung dieses Nachteils werden potentielle Ansätze diskutiert. Und drittens, der direkte Ansatz gibt die Evakuierungsunsicherheiten des komplexen Modells wieder, welche dann die Konsequenzen der Zufallsszenarien deutlich beeinflussen. Aus diesem Grund ist die Evakuierungsunsicherheit für die Risikoanalyse wichtig. Zusätzlich wurde die ’projection array-based design’Methode in dieser Dissertation mit zwei Ansätzen angepasst: der Verknüpfung beider Simulationspläne für FDS und FDS+Evac sowie deren schrittweisen Verfeinerung. Die Effizienz des Metamodels wird durch beide Ansätze erhöht. Diese Ergebnisse führen zu folgenden Schlussfolgerungen: erstens, das Metamodell integriert die Konsequenzen der diskreten Szenarien auf eine effiziente Weise in die Risikoanalyse und ermöglicht dadurch die Berücksichtigung einer höheren Komplexität; und zweitens, das Metamodell stellt einen Fortschritt für Risikoanalysen nicht nur für Straßentunnel sondern auch allgemein im Brandingenieurwesen dar. Aus diesen beiden Gründen kann das Metamodell für andere Methodiken zur Risikoanalyse interessant sein. Zudem ist das Metamodel flexibel auf andere Problemstellungen außerhalb der Risikoanalyse anwendbar, wie z.B. der Bewertung der Bauwerkssicherheit, welche von zeitaufwändigen Untersuchung und mehreren Variablen abhängt. KW - Metamodel KW - Surrogate KW - Uncertainty KW - Risk KW - Consequence KW - Fire KW - Evacuation KW - Tunnel PY - 2019 UR - https://nbn-resolving.org/urn:nbn:de:hbz:468-20200114-101029-6 DO - https://doi.org/10.25926/evq8-h241 SP - 1 EP - 171 PB - Bergische Universität Wuppertal CY - Wuppertal AN - OPUS4-51039 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Raschpichler, C. A1 - Goroncy, C. A1 - Langer, B. A1 - Antonsson, E. A1 - Wassermann, B. A1 - Graf, C. A1 - Klack, Patrick A1 - Lischke, T. A1 - Rühl, E. T1 - Surface Properties and Porosity of Silica Particles Studied by Wide-Angle Soft X-ray Scattering N2 - Wide-angle soft X-ray scattering on free silica particles of different porosity prepared in a beam is reported. The explored q region is mostly dominated by features due to surface roughness and bulk porosity. A comprehensive experimental and theoretical analysis of silica particles of different porosity is presented for various incident photon energies. A correlation analysis, based on the theory of Porod, is used to test the validity of exact Mie theory in different pore density limits. The ability of the discrete dipole scattering model (DDSCAT) to resolve local effects, caused by various pore distributions, is discussed. Characteristic differences between the soft X-ray scattering patterns of the particle samples of different surface properties and porosity are detected. For all mentioned cases, it was confirmed that the effective radius concept of the Guinier model can be successfully extended to Mie theory and DDSCAT in describing the additive contributions of the primary particles, including a thin inhomogeneous solvent-rich surface shell and empty bulk pores. Close agreement, within ±15%, between the calculated and observed pore sizes and porosity values is reached. The influence of pores is alternatively described either in terms of secondary Mie scattering, which is modulated by the local internal electrical field within the particles, or by an independent Mie scattering process induced by the incident field on isolated pores. It is found that for the typical pore/particle size ratios the latter approach presents the best choice. KW - Wide-Angle Soft X‑ray Scattering KW - Silica KW - Porosity PY - 2020 DO - https://doi.org/10.1021/acs.jpcc.0c04308 SN - 1932-7447 SN - 1932-7455 VL - 124 SP - 16663 EP - 16674 AN - OPUS4-51089 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - THES A1 - Schneider, Ronald T1 - Time-variant reliability of deteriorating structural systems conditional on inspection and monitoring data N2 - The current practice of operating and maintaining deteriorating structural systems ensures acceptable levels of structural reliability, but it is not clear how efficient it is. Changing the current prescriptive approach to a risk-based approach has great potential to enable a more efficient management of such systems. Risk-based optimization of operation and maintenance strategies identifies the strategy that optimally balances the cost for controlling deterioration in a structural system with the achieved risk reduction. Inspections and monitoring are essential parts of operation and maintenance strategies. They are typically performed to reduce the uncertainty in the structural condition and inform decisions on future operation and maintenance actions. In risk-based optimization of operation and maintenance strategies, Bayesian updating is used to include information contained in inspection and monitoring data in the prediction of the structural reliability. All computations need to be repeated many times for different potential inspection and monitoring outcomes. This motivates the development of robust and efficient approaches to this computationally challenging task. The reliability of deteriorating structural systems is time-variant because the loads on them and their capacities change with time. In most practical applications, the reliability analysis of deteriorating structural systems can be approached by dividing their lifetime into discrete time intervals. The time-variant reliability problem can then be represented by a series of time-invariant reliability problems. Using this methodology as a starting point, this thesis proposes a novel approach to compute the time-variant reliability of deteriorating structural systems for which inspection and monitoring data are available. The problem is formulated in a nested way in which the prediction of the structural condition is separated from the computation of the structural reliability conditional on the structural condition. Information on the structural condition provided by inspections and monitoring is included in the reliability assessment through Bayesian updating of the system deterioration model employed to predict the structural condition. The updated system reliability is obtained by coupling the updated deterioration model with a probabilistic structural model utilized to calculate the failure probability conditional on the structural condition. This approach is the first main outcome of this thesis and termed nested reliability analysis (NRA) approach. It is demonstrated in two numerical examples considering inspected and monitored steel structures subject to high-cycle fatigue. An alternative – recently developed – approach, which also follows the strategy of discretizing time, describes deteriorating structural systems with hierarchical dynamic Bayesian networks (DBN). DBN combined with approximate or exact inference algorithms also enable the computation of the time-variant reliability of deteriorating structural systems conditional on information provided by inspection and monitoring data. In this thesis – as a proof of concept – a software prototype is developed based on the DBN approach, which can be used to assess the reliability of a corroding concrete box girder for which half-cell potential measurements are available. This is the second main outcome of this thesis. Both approaches presented in this thesis enable an integral reliability analysis of inspected and monitored structures that accounts for system effects arising from (a) the correlation among deterioration states of different structural elements, (b) the interaction between element deterioration and system failure, and (c) the indirect information gained on the condition of all unobserved structural elements from inspecting or monitoring the condition of some structural elements. Thus, both approaches enable a systemwide risk-based optimization of operation and maintenance strategies for deteriorating structural systems. The NRA approach can be implemented relatively easily with subset simulation, which is a sequential Monte Carlo method suitable for estimating rare event probabilities. Subset simulation is robust and considerably more efficient than crude Monte Carlo simulation. It is, however, still sampling-based and its efficiency is thus a function of the number of inspection and monitoring outcomes, as well as the value of the simulated event probabilities. The current implementation of the NRA approach performs separate subset simulation runs to estimate the reliability at different points in time. The efficiency of the NRA approach with subset simulation can be significantly improved by exploiting the fact that failure events in different years are nested. The lifetime reliability of deteriorating structural systems can thus be computed in reverse chronological order in a single subset simulation run. The implementation of the DBN approach is much more demanding than the implementation of the NRA approach but it has two main advantages. Firstly, the graphical format of the DBN facilitates the presentation of the model and the underlying assumptions to stakeholders who are not experts in reliability analysis. Secondly, it can be combined with exact inference algorithms. In this case, its efficiency neither depends on the number of inspection and monitoring outcomes, nor on the value of the event probabilities to be calculated. However, in contrast to the NRA approach with subset simulation, the DBN approach with exact inference imposes restrictions on the number of random variables and the dependence structure that can be implemented in the model. T3 - BAM Dissertationsreihe - 168 KW - Reliability KW - Structural systems KW - Deterioration KW - Bayesian analysis KW - Inspection KW - Monitoring KW - Zuverlässigkeit KW - Tragstrukturen KW - Schädigungsprozesse KW - Bayes'sche Analyse KW - Inspektion KW - Monitoring PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-512977 SN - 1613-4249 VL - 168 SP - 1 EP - 188 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-51297 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - THES A1 - Aristia, Gabriela T1 - Polyaniline/Silicon Dioxide Composite-Based Coating for Corrosion Protection in Geothermal Systems N2 - Geothermal energy is one of the cleanest renewable alternatives to reduce the dependency on fossil fuel [1, 2]. Despite its promising future, its implementation faces various challenges, one of them being corrosion processes. To implement this energy, hot fluids are pumped from a geothermal well. These hot fluids originate from deep within the earth, so consist of different ionic species and gases in a wide range of temperatures, which lead to their corrosive nature. In terms of geothermal energy resources, Indonesia is at the forefront, with the highest preserved geothermal energy in the world of about 29 GWe and 312 potential geothermal locations [3]. Geothermal wells in Sibayak (North Sumatera), Indonesia, belong to young stratovolcanoes and have operating temperatures varying from 36 °C at the near ground surface to 310 °C at the bottom of the well, which is liquid-dominated with acidic and saline properties [4, 5]. Therefore, this geothermal fluid creates an aggressive environment that is conducive to corrosion of the powerplant infrastructure. Parts of the geothermal powerplant infrastructure, such as pipelines and heat exchangers, are commonly made of metals, e.g. carbon steel and stainless steel. Consequently, they may undergo corrosion and scaling when exposed to the geothermal fluid, especially for carbon steel. To ensure the safety and longevity of a geothermal powerplant, the infrastructure is constructed of expensive corrosion resistant alloys [6–10], e.g., titanium and Ni-Cr based alloys, or carbon steel which needs to be protected by coatings or inhibitors. To address the corrosion of carbon steel in the geothermal environment, artificial geothermal water was used to simulate a geothermal well in Sibayak, Indonesia, with pH 4 and a saline composition of 1,500 mg/l Cl-, 20 mg/l SO42-, 15 mg/l HCO3-, 200 mg/l Ca2+, 250 mg/l K+, and 600 mg/l Na+. Carbon steel underwent the most severe corrosion at 150°C in an oxygen-containing solution with a corrosion rate of 0.34 mm/year, which is approximately ten times higher than that in the absence of dissolved oxygen. In all conditions, pitting corrosion was observed, which necessitate a protection strategy on carbon steel. In order to promote a cost effective and locally available option, this work focused on an easily applicable coating which utilized local resources. Toward developing such protective coating based on the locally available resources in Indonesia which can yield good corrosion resistance and thermal stability in geothermal environment, two additional components, i.e. polyaniline (PANI) and silicon dioxide, were used to modify an alkyd-based commercial coating. The selection of the alkyd-based coating as a matrix focused on the industrial convenience basis, where the coating application procedure should be simple and easy to apply within reasonable costs. The alkyd-based coating underwent severe blistering when exposed to the artificial geothermal water at 70 and 150°C due to the reaction between CaCO3 (as one of its components) and the artificial geothermal water, as well as a possible alkyd hydrolysis in the initial stage of exposure. In the oxygen-free solution, the degradation was controlled by chemical and thermal reactions, whereas in the aerated condition, oxidization at the coating surface further accelerated polymer degradation. PANI was chosen as one of the anticorrosion pigments which was widely developed over the past decades. To investigate the interaction between PANI and the artificial geothermal water, PANI film was electrochemically deposited on the carbon steel surface and exposed to the artificial geothermal water. Electrochemically synthesized oxalate-doped PANI was protective against corrosion of carbon steel in artificial geothermal water at room temperature. The mechanism involved an exchange of electroactive species within the coating layer, as confirmed by electrochemical impedance spectra. Interaction of ionic species, such as Cl-, Na+, Ca2+ from the artificial geothermal water, with the outer layer of PANI is suggested both at 25°C and 150°C, based on the EDX spectra of the coating surface after exposure to the artificial geothermal water. Thus, the protection mechanism of PANI is not solely based on the physical barrier layer properties, but rather associated with the redox mediated properties of PANI, which selectively allow ionic species intrusion from the electrolyte into the PANI layer. Although PANI is a promising candidate as an anticorrosion coating, its morphological characterization reveals that electrochemically deposited PANI is not stable for an application at 150°C. Therefore, another approach was used to promote better protective behavior of PANI by dispersing chemically synthesized PANI in the alkyd-based coating. To enhance the thermal stability of the coating, silicon dioxide (SiO2) was added, which was able to prolong the sustainability of coated metals until 28 days compared to the unmodified alkyd-based coating, which underwent a change in color to brown/orange only within 7 days of exposure. This improvement might be associated with the role of SiO2 to proportionate the thermal expansion coefficient of the coating system to be compatible with that of carbon steel. Although the coating is thermally enhanced, the electrolyte might still intrude through the coating resulting in the change of coating color after 28 days of exposure in the artificial geothermal water. When PANI was added, the coating system provided an active corrosion protection on the carbon steel surface. The chemical and morphological characterization of the PANI-alkyd and SiO2-alkyd coating system showed that coatings were improved, and no blisters were observed, albeit the degradation continued. Based on the results of exposure tests, the combined coating system was further investigated. The combinational coating of PANI/SiO2-alkyd was used with 2 wt% of PANI and 15 wt% of SiO2. Electrochemical tests indicated cathodic protection at 150°C, as the Ecorr of PANI/SiO2 remained approximately 400 mV lower than the carbon steel potential. The impedance spectra of the combinational coating of PANI/SiO2 showed a continuous decrease in the absolute impedance value over time. A significant decrease was observed within one day of exposure, followed by a slow gradual decrease, which might be associated with water absorption in the coating. FTIR spectra revealed that several peaks associated with the organic portion of the coatings were reduced after the specimens were exposed for 6 months. However, the absorption peaks related to the inorganic portion of the coatings remained stable until 6 months. Morphological characterization of the combinational coating of PANI/SiO2 showed that there were no blisters or significant discoloration of coatings after long-term exposure for 6 months in artificial geothermal water at 150°C, indicating that the chemical degradation does not significantly affect the functionality of the coating. This clearly shows the durability of PANI/SiO2 coating in the geothermal condition, suggesting that this coating can be used for such geothermal application. However, further testing of this coating should be conducted in a real geothermal environment on-site to ensure safety and viability. KW - Geothermal KW - Corrosion KW - Coating KW - Polyaniline KW - Electrochemical impedance spectroscopy PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:188-refubium-26704-6 UR - https://refubium.fu-berlin.de/handle/fub188/26704 DO - https://doi.org/10.17169/refubium-26461 SP - 1 EP - 175 CY - Berlin AN - OPUS4-51281 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - THES A1 - Otto, Peter T1 - Explicit dynamics and regularization in impact simulation N2 - Die Simulation des Materialverhaltens für ein Aufprallproblem erfordert sowohl präzise Methoden für die Kontaktformulierung als auch für die Wellenausbreitung nach dem Aufprall. Das numerische Modell des Aufprallproblems ist schlecht gestellt, weil die plötzliche Änderung der Geschwindigkeiten im Kontaktbereich zu unbegrenzten Beschleunigungen bei gleichzeitig kleiner werdenden Zeitschritten führt. Daraus resultieren Oszillationen in den Kontaktspannungen, die sich im Material ausbreiten. Bei einem dehnratenabhängigen Material, wie z.B. Beton, führen diese Oszillationen zu erheblichen numerischen Fehlern und falschen Vorhersagen für die Festigkeit des Materials. Eine Regularisierung ist daher erforderlich, um die Oszillationen zu vermeiden. Ein weiterer wichtiger Punkt ist die numerische Lösung des Kontaktproblems. Bei der Simulation des Aufprallproblems muss das nichtlineare Kontaktproblem in jedem Zeitschritt gelöst werden. Die Mortar-Methode mit der Segmentierung des Kontaktbereichs hat sich als sehr präzise erwiesen, stellt aber ein rechen- und entwicklungstechnisch aufwendiges Verfahren, vor allem für 3D Probleme, dar. Die numerische Modellierung des nachfolgenden Wellenausbreitungsproblems erfordert kleine Zeitschritte, um die Ausbreitung der Welle genau zu erfassen. Implizite Verfahren sind deshalb zu aufwendig. Explizite Verfahren sind effizient, allerdings nur wenn die Massenmatrix diagonal ist. In diesem Fall wird die Lösung eines linearen Gleichungssystems in jedem Zeitschritt vermieden. In dieser Arbeit wird für die numerische Lösung des Kontaktproblems ein gekoppelter finite Elemente - Non-Uniform Rational B-Spline (FE-NURBS) Ansatz verwendet. In dem gekoppelten Ansatz, wird eine NURBS Kurve bzw. Oberfläche zwischen die im Kontakt befindlichen Körper gebracht. Die Körper sind mit finiten Elementen vernetzt und die NURBS Schicht wird verwendet, um die Kontaktkräfte zu berechnen. Dadurch wird eine glatte isogeometrische Kontaktformulierung erreicht. Folglich kann eine Segmentierung des Kontaktbereichs vermieden und eine effiziente elementweise Integration zur Berechnung der Kontaktkräfte eingesetzt werden. Die Regularisierung des Aufprallproblems erfolgt mit einer nichtlinearen Penalty-Formulierung. Die Penalty-Funktion ist ein Polynom, was einen glatten Übergang zwischen Nicht-Kontakt und Kontakt während des Aufpralls ermöglicht. Die Penalty-Formulierung ist netzabhängig und wird steifer mit feiner werdendem Netz, wobei Oszillationen in den Kontaktpannungen weiterhin nicht auftreten. Zur effizienten Raum- und Zeitdiskretisierung für das Wellenausbreitungsproblem werden Verfahren höherer Ordnung eingesetzt. Explizite Zeitintegration wird kombiniert mit Raumdiskretisierung, die mit spektralen finiten Elementen erfolgt. N2 - The simulation of the structural response for impact scenarios strongly requires an accurate simulation of both the impact event as well as the subsequent wave propagation. The numerical modeling of the impact event is intrinsically ill-posed due to the instantaneous changes of velocities in the contact area, leading to unbounded accelerations for decreasing time steps which causes oscillations in the contact stresses. These oscillations then propagate into the bulk material. Using a rate dependent material model, like concrete, they might lead to significant errors and a wrong prediction of the structural response. A regularization is thus required to avoid oscillations in the contact stresses. Another issue is related to the numerical computation of the contact conditions. In impact simulations, the nonlinear contact computation needs to be evaluated in every time step. A segmentation technique of the contact area is accurate but time consuming and may result in a bottleneck for the simulation and implementation, especially for 3D problems. The modeling of the subsequent wave propagation requires small time steps, which is primarily due to accuracy reasons. Implicit schemes are thus not affordable. Explicit time integration schemes are efficient only for diagonal mass matrices, as in this case no solution of a linear system is required. In this work, a coupled finite element - Non-Uniform Rational B-Spline (FE-NURBS) approach is applied to impact problems. The coupled approach uses an intermediate NURBS layer to compute the contact forces between the contacting bodies discretized by FEs. The advantages of a smooth isogeometric contact formulation are used to compute the contact forces. A segmentation of the contact area is avoided and an efficient element-based integration is used. The impact event is regularized using a mesh dependent nonlinear penalty approach. The penalty function is a polynomial which ensures a smooth transition between the noncontact and the contact state during the impact. For finer meshes, the penalty regularization becomes stiffer while still avoiding artificial oscillations in the contact stresses. Efficient higher order space and time discretizations are used to model the wave propagation. Explicit time integration is combined with higher order spectral element spatial discretization. KW - Explicit dynamics KW - Impact simulation KW - Isogeometric analysis KW - Mortar method KW - Spectral elements PY - 2019 SN - 978-3-920395-70-8 SP - 1 EP - 104 CY - Braunschweig AN - OPUS4-51032 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Auersch, Lutz A1 - Said, Samir T1 - Slab track behaviour under train passage and hammer impact – Measurements at different sites and calculated track interaction with continuous soils N2 - This contribution intends to give an overview on the vibration behaviour of slab tracks in comparison of measurements and calculations and also by comparison of different track types at more than ten different measuring sites. In theory, tracks on continuous soil are calculated by the frequency-wavenumber domain method. In experiment, geophone measurements are transformed to displacement results. Two aspects of track behaviour are considered, the frequency-dependant compliance of the track, measured by hammer impact, and the deflection under a passing axle load. In theory, the response to a single axle can be calculated, whereas in experiment, only the passage of the whole train can be measured. For comparison of theory and experiment, the calculated deflection under a single axle is superposed to get the response of the whole train. As a result, the slab track characteristics are completely different from the ballast track characteristics where each axle can be seen in the time histories. The slab track has a more global behaviour where only a whole bogie can be found in the track response and moreover, the two neighbouring bogies are not completely separated. The measurement of the different track elements (rail, sleeper, track plate, base layer) and the frequency-dependant compliances with possible resonances yield further information About the properties of the track elements. The calculations show that the soil has the dominant influence on the amplitudes and the width of the track-plate displacements. In the measurement results, the following parameters are analysed: slab track vs. ballast track, different types of slab tracks, damaged slab tracks, different trains, switches at different measuring points, voided sleepers, an elastic layer, the mortar layer, and different soils at different places. Finally, a good agreement between measured and calculated results is found for the normal and some special (damaged, floating) slab tracks. KW - Slab track KW - Train passage KW - Hammer impact KW - Compliance function KW - Track deflection PY - 2020 UR - https://iiav.org/ijav/index.php?va=viewpage&vaid=177&id_number=95 DO - https://doi.org/10.20855/ijav.2020.25.31622 SN - 1027-5851 VL - 25 IS - 3 SP - 341 EP - 354 PB - International Institute of Acoustics and Vibration CY - Gliwice AN - OPUS4-51346 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Auersch, Lutz T1 - Vehicle-Track-Soil Interaction of Isolated, Un-isolated and Damaged Railway Tracks N2 - This article deals with two topics of vehicle-track-soil interaction, the mitigation of railway induced ground vibration by soft track elements, and the identification of track damage. Theoretical results have been achieved by a combined finite-element boundary-element method (FEBEM). The theoretical results are confronted with measurements at four sites. Improved mitigation effects have been found for soft rail pads under heavy sleepers. The insertion loss, however, can be too optimistic if a strong vehicle track resonance occurs for the un-isolated reference track. Two measurement sites show this strong vehicle-track resonance at about 80 Hz, which has been approximated by using the results of a wide parameter study including the rail pad, ballast, and soil stiffness, as well as the ballast model and the soil layering. – The detection of slab track damage is mainly based on the differences of the receptance or compliance functions. Theoretical results have been confirmed by measurements at one site where a loss of contact between track plate and base layer was visible. Measurements at a second site with a hidden damage have been compared with the theoretical results of a loose sleeper. The differences between intact (or repaired) and damaged tracks are strong enough to encourage the further development of this method for the identification of track damages. KW - Railway track KW - Track-soil interaction KW - Ground vibration KW - Mitigation KW - Under-sleeper pads KW - Track damage monitoring PY - 2020 DO - https://doi.org/10.4203/ijrt.6.3.2 SN - 2049-5358 VL - 2 IS - 20 SP - 21 EP - 49 PB - Saxe-Coburg Publications CY - London AN - OPUS4-51257 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Erning, Johann Wilhelm T1 - Corrosion behaviour of printed 1.4404 in drinking water systems N2 - The regulations for materials in contact with drinking water require tests to evaluate the hygienic properties of the materials. A printed 1.4404 was tested according to EN 16056 and the suitability for the use in drinking water was proven. T2 - Eurocorr 2020 CY - Online meeting DA - 07.09.2020 KW - Passivity KW - Drinking water KW - Stainless steel KW - Additive manufacturing PY - 2020 AN - OPUS4-51237 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Häßler, Dustin A1 - Häßler, M. A1 - Hothan, Sascha A1 - Krüger, Simone T1 - Reaktive Brandschutzsysteme auf Stahlbauteilen mit doppelt gekrümmter Oberfläche N2 - Reaktive Brandschutzsysteme können die Feuerwiderstandsdauer von Stahlbauteilen signifikant erhöhen. Im Brandfall schäumt das reaktive Brandschutzsystem auf und bildet um das Stahlbauteil eine thermische Schutzschicht aus. Dadurch wird die Erwärmung des Stahls verlangsamt und der temperaturbedingte Festigkeitsverlust verzögert. Reaktive Brandschutzsysteme werden überwiegend in drei Bereichen angewendet: Hochbau, Offshore bzw. maritimer Sektor sowie Tank- bzw. Behälterbau. Insbesondere bei Stahltanks und -behältern sind häufig einfach oder auch doppelt gekrümmte Bauteiloberflächen anzutreffen. Aufgrund des meist begrenzten seitlichen Expansionsvermögens von reaktiven Brandschutzsystemen kann es bei Bauteilen mit konvexer Oberflächenkrümmung zu einer Intensivierung der Rissbildung im Schaum kommen, wodurch sich häufig die thermische Schutzwirkung verschlechtert. Da zum Thema des Einflusses der Oberflächenkrümmung auf die Leistungsfähigkeit reaktiver Brandschutzsysteme bisher kaum Untersuchungen vorliegen, wurden exemplarisch zwei Tankböden mit zwei verschiedenen Trockenschichtdicken eines reaktiven Brandschutzsystems einer Brandprüfung unterzogen. Bei gleicher Trockenschichtdicke des reaktiven Brandschutzsystems zeigten die Tankböden eine wesentlich schnellere Erwärmung als ebene Stahlplatten mit vergleichbarem Profilfaktor. Die Brandprüfungen und die Ergebnisse zum Einfluss der Oberflächenkrümmung werden im Beitrag ausführlich vorgestellt und diskutiert. KW - Brandschutz KW - Stahl KW - Reaktive Brandschutzsysteme KW - Behälter KW - Intumeszierende Beschichtung PY - 2020 DO - https://doi.org/10.1002/stab.201900095 VL - 89 IS - 9 SP - 794 EP - 800 PB - Ernst & Sohn Verlag CY - Berlin AN - OPUS4-51242 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Wagner, Adrian T1 - Korrosionsuntersuchungen in Erdböden N2 - Das korrosionsverhalten von metallenen Werkstoffen in Erdböden besitzt unter Betrachtung der Dauerhaftigkeit sowie aus wirtschaftlichen Gesichtspunkten eine entscheidende Bedeutung. Um zu überprüfen, ob ein metallener Werkstoff für eine bestimmte Bodenklasse geeignet/ beständig ist, müssen oftmals elektrochemische Korrosionsuntersuchungen im Boden durchgeführt werden. Da sich natürliche Böden aufgrund ihrer organischen Bestandteile mit der Zeit verändern, sind die Ergebnisse der Korrosionsuntersuchungen nicht reproduzierbar. Ziel dieser Untersuchungen ist es, künstliche Böden herzustellen, die aufgrund ihrer Eigenschaften (Bodenparameter) Bodenklassen der DIN 50292-3 zuzuordnen sind um zukünftig reproduzierbare Ergebnisse im Labor generieren zu können. T2 - 15. Sitzung des NA 062-01-77 AA "Korrosionsprüfverfahren" CY - Online meeting DA - 28.10.2020 KW - Korrosionsuntersuchungen in Böden KW - DIN 50929-3 KW - Deckschichtwiderstand KW - Auslagerungsversuch KW - Korrosion PY - 2020 AN - OPUS4-51521 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Günther, Martin A1 - Lorenzetti, A. A1 - Schartel, Bernhard T1 - From Cells to Residues: Flame-Retarded Rigid Polyurethane Foams N2 - Rigid polyurethane foams (RPUFs) exhibit short times to ignition as well as rapid flame spread and are therefore considered to be hazardous materials. This paper focuses on the fire phenomena of RPUFs, which were investigated through a multimethodological approach. Water-blown polyurethane (PUR) foams without flame retardants (FRs) as well as waterblown PUR foams containing triethyl phosphate as a gas phase-active FR were examined. The aim of this study is to clarify the influence of the FR on the fire phenomena during combustion of the foams. Additionally, materials’ densitieswere varied to range from 30 to 100 kg/m3. Thermophysical properties were studied bymeans of thermogravimetry; fire behavior and flammability were investigated via cone calorimeter and limiting Oxygen index, respectively. During the cone calorimeter test, the temperature development inside the burning specimens was monitored with thermocouples, and cross sections of quenched specimens were examined visually, giving insight into the morphological changes during combustion. The present paper delivers a comprehensive study, illuminating phenomena occurring during foam combustion and the influence of a FR active in the gas phase. The superior fire performance of flameretarded PUR foams was found to be based on flame inhibition, and on increased char yield leading to a more effective protective layer. It was proven that in-depth absorption of radiation is a significant factor for estimation of time to ignition. Cross sections investigated with the electron scanning microscope exhibited a pyrolysis front with an intact foam structure underneath. The measurement of temperature development inside burning specimens implied a shift of burning behavior towards that of non-cellular materials with rising foam density. KW - Polyurethane KW - Rigid foams KW - Fire behavior PY - 2020 DO - https://doi.org/10.1080/00102202.2019.1634060 SN - 0010-2202 SN - 1563-521X VL - 192 IS - 12 SP - 2209 EP - 2237 PB - Taylor & Francis AN - OPUS4-51483 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Bäßler, Ralph T1 - Rezension: Schweißen im Stahlbau, Normen für die Herstellerqualifikation nach DIN EN 1090‐1 N2 - Schlosserei‐, Metall‐ und Stahlbaubetriebe müssen seit Juli 2012 für tragende Bauteile aus Stahl und Aluminium, die als Bauprodukte in Verkehr gebracht werden sollen, einen Konformitätsnachweis nach DIN EN 1090‐1 erbringen. Mit der sechsten Auflage des Normen‐Handbuches „Schweißen im Stahlbau“ setzen das Deutsche Institut für Normung e.V. (DIN) und der Deutsche Verband für Schweißen und verwandte Verfahren e.V. (DVS) ihre bewährte Strategie fort, die dieses Thema betreffenden aktuellen Normen und Regelwerke durch J. W. Mußmann in gut aufbereiteter Form kompakt zusammenzustellen. KW - Korrosion KW - Schweißen KW - Schweißnaht PY - 2020 DO - https://doi.org/10.1002/maco.202070116 SN - 1521-4176 SN - 0947-5117 VL - 71 IS - 11 SP - 3 EP - 4 PB - WILEY‐VCH Verlag GmbH & Co. KGaA CY - Weinheim AN - OPUS4-51512 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Bäßler, Ralph T1 - Review: Materials Informatics -Metals, Tools and Applications N2 - Since data processing has now also found its way into materials science, there has been a great demand from users for a corresponding textbook. This book provides a guide to the latest advances of materials informatics and data mining for materials science. 46 authors introduce readers to methods, present tools and case studies to illustrate the power of materials informatics within this new field of application. KW - Corrosion KW - Materials behavior PY - 2020 DO - https://doi.org/10.1002/maco.202070114 SN - 1521-4176 SN - 0947-5117 VL - 71 IS - 11 SP - 1928 EP - 1929 PB - WILEY‐VCH Verlag GmbH & Co. KGaA CY - Weinheim AN - OPUS4-51513 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bäßler, Ralph T1 - Review: Science, Technology and Applications of Metals in Additive Manufacturing N2 - Often 3D‐printing and additive manufacturing are mentioned as the 3rd industrial revolution. In this conjunction this book provides a brief overview on additively manufactured metal pieces. This book fulfills its intension to serve as an educational guide, providing a holistic picture encompassing science, technology and applications for the real‐life use of Metal Additive Manufacturing. KW - Additive manufacturing KW - Corrosion KW - Material properties PY - 2020 DO - https://doi.org/10.1002/maco.202070114 SN - 1521-4176 SN - 0947-5117 VL - 71 IS - 11 SP - 1929 EP - 1930 PB - WILEY‐VCH Verlag GmbH & Co. KGaA CY - Weinheim AN - OPUS4-51514 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Auersch, Lutz T1 - Simple and fast prediction of train-induced track forces, ground and building vibrations N2 - A simple and fast prediction scheme is presented for train induced ground and building vibrations. Simple models such as (1-dimensional) transfer matrices are used for the vehicle-track-soil interaction and for the building-soil interaction. The wave propagation through layered soils is approximated by a frequency-dependent homogeneous half-space. The prediction is divided into the parts “emission” (excitation by railway traffic), “transmission” (wave propagation through the soil) and “immission” (transfer into a building). The link between the modules is made by the excitation force between emission and transmission, and by the free-field vibration between transmission and immission. All formula for the simple vehicle-track, soil and building models are given in this article. The behaviour of the models is demonstrated by typical examples, that is the mitigation of train vibrations by elastic track elements, the low- and high-frequency cut-offs characteristic for layered soils, and the interacting soil, wall and floor resonances of multi-storey buildings. It is shown that the results of the simple prediction models can well represent the behaviour of the more time-consuming detailed models, the finite-element boundary-element models of the track, the wavenumber integrals for the soil, and the three-dimensional finite-element models of the building. In addition, measurement examples are given for each part of the prediction confirming that the methods provide reasonable results. As the prediction models are fast in calculation, many predictions can be done, for example to assess the environmental effect along a new railway line. The simple models have the additional advantage that the user needs to know only a minimum of parameters. So, the prediction is fast and user-friendly, but also theoretically and experimentally well-founded. KW - Railway induced vibration KW - Ground vibration KW - Layered soil KW - Building response KW - Excitation forces KW - Track and vehicle irregularities PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-513340 DO - https://doi.org/10.1007/s40534-020-00218-7 SN - 2662-4745 VL - 28 IS - 3 SP - 232 EP - 250 PB - Springer AN - OPUS4-51334 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Erning, Johann Wilhelm T1 - Planung und Betrieb von Trinkwasserinstallationen: Was uns das Regelwerk sagt N2 - Die gesetzlichen und technischen Regeln für Planung, Bau und Betrieb einer Trinkwasserinstallation werden dargestellt. Beispiele für einzelne Punkte werden gegeben. T2 - Der sichere Einsatz von Werkstoffen aus Kupfer und Kupferlegierungen in der Trinkwasserinstallation CY - Online meeting DA - 21.10.2020 KW - Trinkwasser KW - Werkstoffe KW - Korrosion KW - Hygiene PY - 2020 AN - OPUS4-51454 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Bäßler, Ralph T1 - Rezension: Analytik - Daten, Formeln, Übungsaufgaben N2 - Seit seiner erstmaligen Veröffentlichung im Jahre 1894 als „Logarithmische Rechentafeln für Chemiker“ und ab 1982 als „Rechentafeln für die chemische Analyse“ begleitet der „Küster‐Thiel“ Generationen nicht nur von Laborantinnen und Laboranten sowie Studierende hilfreich bei der analytischen Arbeit. Mit der 108. Auflage änderte sich 2016 der Titel dieses in der „Studium“‐Reihe des De Gruyter Verlages herausgegebenen Standardwerkes ein weiteres Mal. Die 109. Auflage des Klassikers der chemischen Analytik‐Literatur setzt die Tradition fort, mit zahlreichen anschaulichen Erklärungen, Beispiele und Rechnungen Chemikern, Physikern und Ingenieurswissenschaftlern an Universitäten und Fachhochschulen; Auszubildenden und Laboranten ein übersichtliches und aktuelles Arbeitsmittel für den analytischen Alltag zur Verfügung zu stellen. Nutzern früherer Ausgaben wird der Umstieg auf die neue Ausgabe empfohlen, damit auch sie auf dem neuesten Stand arbeiten können. KW - Analyse KW - Labor KW - Formeln KW - Laborarbeit PY - 2020 DO - https://doi.org/10.1002/maco.202070106 SN - 1521-4176 SN - 0947-5117 VL - 71 IS - 10 SP - 2 EP - 3 PB - WILEY‐VCH Verlag GmbH & Co. KGaA CY - Weinheim AN - OPUS4-51415 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Long, Lijia A1 - Anh Mai, Q. A1 - Morato, P. G. A1 - Dalsgaard Sorensen, J. A1 - Thöns, Sebastian T1 - Information value-based optimization of structural and environmental monitoring for offshore wind turbines support structures N2 - The use of load and structural performance measurement information is vital for efficient structural integrity management and for the cost of energy production with Offshore Wind Turbines (OWTs). OWTs are dynamically sensitive structures subject to an interaction with a control unit exposed to repeated cyclic wind and wave loads causing deterioration and fatigue. This study focuses on the quantification of the value of structural and environmental information on the integrity management of OWT structures, with the focus on fatigue of welded joints. By utilizing decision analysis, structural reliability methods, measurement data, as well as the cost-benefit models, a Value of Information (VoI) analysis can be performed to quantify the most beneficial measurement strategy. The VoI assessment is demonstrated for the integrity management of a butt welded joint of a monopile support structure for a 3 MW OWT with a hub height of approximately 71m. The conditional value of three-year measured oceanographic information and one-year strain monitoring information is quantified posteriori in conjunction with an inspection and repair planning. This paper provides insights on how much benefits can be achieved through structural and environmental information, with practical relevance on reliability-based maintenance of OWT structures. KW - Structural health monitoring KW - Offshore wind turbine KW - Monopile support structure KW - Value of information KW - Weld fatigue KW - Decision tree KW - Dynamic Bayesian Network PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-514098 DO - https://doi.org/10.1016/j.renene.2020.06.038 VL - 10 IS - 159 SP - 1036 EP - 1046 PB - Elsevier Ltd. AN - OPUS4-51409 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schartel, Bernhard T1 - Flammschutz für Polymere in der Elektrotechnik N2 - Das Brandverhalten stellt wie das elektrische Isolationsverhalten, die geringen elektrischen Verluste, die Verarbeitbarkeit und Formbarkeit eine der wesentlichen Schlüsseleigenschaften im Eigenschaftsprofil von Polymerwerkstoffen in der Elektrotechnik dar. Dabei bedarf es einer Ausrüstung der Polymere mit Flammschutzmittel. Die Entwicklung von immer effizienteren, synergistischen und multifunktionalen Multikomponentensystemen ist dabei eine herausragende Quelle für Innovation. Die Verbesserung der werkstoff- und anwendungsspezifischen Flammschutzlösungen bestimmen die aktuellen und zukünftigen Polymermaterialien in der Elektrotechnik mit. Der Vortrag stellt anhand von Beispielen einige der erfolgreichen Konzepte dar. Es wird versucht, über das wissenschaftlich systematische Verständnis Grundprinzipien und Lösungsstrategien zu verdeutlichen. T2 - Vortrag des Monats Oktober 2020, Neue Materialien Bayreuth GmbH CY - Bayreuth, Germany DA - 06.10.2020 KW - Flammschutzmittel KW - Elektrotechnik KW - Brandtests KW - Synergie KW - Multikomponentensysteme PY - 2020 AN - OPUS4-51410 LA - mul AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Tornaghi, M. L. A1 - Tsionis, G. A1 - Pegon, P. A1 - Molina, J. A1 - Peroni, M. A1 - Korzen, Manfred A1 - Tondini, N. A1 - Covi, P. A1 - Abbiati, G. A1 - Antonelli, M. A1 - Gilardi, B. T1 - Experimental study of braced steel frames subjected to fire after earthquake N2 - The EQUFIRE project aims to study the post-earthquake fire Performance of steel frame structures and is part of the Transnational Access activities of the SERA project (www.sera-eu.org) at the ELSA Reaction Wall of the European Commission - Joint Research Centre. As it has happened in many historical occasions, after an earthquake, earthquakeinduced rupture of gas piping, failure of electrical systems, etc. may trigger fire. The structural fire performance can deteriorate because the fire acts on a previously damaged structure. In addition, the earthquake may have damaged fire protection elements and the fire can spread more rapidly if compartmentation walls have failed. This is particularly relevant for steel structures as the high thermal conductivity of elements with small thickness entails quick temperature rise with consequent fast loss of strength and stiffness. EQUFIRE studied a four-storey three-bay steel frame with concentric bracings in the central bay. The structure was designed for reference peak ground acceleration equal to 0.186g, soil type B and type 1 elastic response spectrum according to Eurocode 8. Tests were performed at the ELSA Reaction Wall and at the furnace of the Federal Institute for Materials Research and Testing (BAM). The experimental activities at the ELSA Reaction Wall comprise pseudo-dynamic tests on a full-scale specimen of the first storey of the building, while the upper three storeys are numerically simulated. The aim is to study the response of the structure and fire protection elements, including their interaction, under the design earthquake and for different configurations: bare frame without fire protection, specimen with three fire protection solutions (conventional and seismic-resistant boards, and vermiculite sprayed coating) applied on the bracing and one column, and with conventional and seismic-resistant fire barrier walls built in the two external bays of the specimen. The testing programme at BAM included fire tests of five columns (two specimens without fire protection elements and three specimens with the types of fire protection mentioned above). Before the fire test, each column was subjected to a horizontal and vertical displacement history resulting from the seismic action. During the fire tests, the effect of the surrounding structure was simulated by limiting the axial thermal expansion. The experimental results will serve to study the response of structural and non-structural components to fire following earthquake scenarios, with a view to improving existing design guidelines and future standards. T2 - The 17th World Conference on Earthquake Engineering - 17WCEE CY - Meeting was canceled DA - 13.09.2020 KW - Fire following earthquake KW - Concentrically braced steel frames KW - Large-scale tests KW - Pseudo-dynamic testing KW - Substructuring PY - 2020 SP - 2i-0104-1 EP - 2i-0104-12 AN - OPUS4-51426 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz T1 - A mid-frequency component of train-induced ground vibration due to scattered axle impulses and the irregularities of the soil and ballast N2 - The passage of the train is dominated by the impulses of the static axle loads. The response of the regular homogeneous and irregular soils has been calculated by the finite-element method in frequency domain. The superposition of the impulse responses yields the quasi-static component of the ground vibration which is restricted to very low frequencies and to the close near-field of the track. In case of an irregular soil or ballast of which the stiffness varies randomly in space, a mid-frequency ground vibration component is generated by the scattering of the axle impulses. Measurements will be shown which prove the existence of the mid-frequency ground vibration component and the unique explanation by the scattered axle impulses: many international measurements with a raised mid-frequency component, axle-box measurements with a too low mid-frequency dynamic load, amplitude-speed dependencies which are incompatible with irregularity-induced dynamic loads, and ground vibration reductions due to stiff track elements. T2 - International Conference on Noise and Vibration Engineering (ISMA/USD) CY - Online meeting DA - 07.09.2020 KW - Ground vibration KW - Railway KW - Irregular soil KW - Irregular ballast KW - Axle impulses PY - 2020 SP - 2611 EP - 2625 PB - KULeuven CY - Leuven AN - OPUS4-51210 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz A1 - Said, Samir A1 - Rohrmann, R. T1 - Natural frequencies and modes of poles, beams, floors, road and rail bridges N2 - In the last three decades, the vibrations of many floors and bridges have been measured. The contribution shows some evaluation methods, experimental results and some modelling and theoretical results. Simple evaluation methods have been developed for single and coupled floors. Two coupled beams have been measured in good agreement with the theory. A more complex coupling model has been found for a large wooden floor in a castle consisting of six floor bays which correlates well with the measurements. Damaged and intact poles have been tested by their natural frequencies and damping values, and a fair correlation between the degree of damage and the shift of the frequency. Road bridges have been analysed in detail and some examples are presented. Railway bridges and trains are studied for resonant excitation. The risk of resonance can be estimated in frequency domain by using axle-sequence spectra of the train and the natural frequencies of the bridge. A measurement example shows the amplification, but even stronger the cancellation of the subsequent axle responses. Several high-speed trains and freight trains have been analysed for their potential resonance amplification. T2 - International Conference on Noise and Vibration Engineering (ISMA/USD 2020) CY - Online meeting DA - 07.09.2020 KW - Modalanalyse KW - Bauwerke KW - Bauteile KW - Brücken KW - Achsfolgespektren PY - 2020 SP - 1573 EP - 1585 PB - KULeuven CY - Leuven AN - OPUS4-51211 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz T1 - A mid-frequency component of train-induced ground vibration due to scattered axle impulses and the irregularities of the soil and ballast N2 - The passage of the train is dominated by the impulses of the static axle loads. The response of the regular homogeneous and irregular soils has been calculated by the finite-element method in frequency domain. The superposition of the impulse responses yields the quasi-static component of the ground vibration which is restricted to very low frequencies and to the close near-field of the track. In case of an irregular soil or ballast of which the stiffness varies randomly in space, a mid-frequency ground vibration component is generated by the scattering of the axle impulses. Measurements will be shown which prove the existence of the mid-frequency ground vibration component and the unique explanation by the scattered axle impulses: many international measurements with a raised mid-frequency component, axle-box measurements with a too low mid-frequency dynamic load, amplitude-speed dependencies which are incompatible with irregularity-induced dynamic loads, and ground vibration reductions due to stiff track elements. T2 - International Conference on Noise and Vibration Engineering (ISMA/USD 2020) CY - Online meeting DA - 07.09.2020 KW - Ground vibration KW - Railway KW - Irregular soil KW - Irregular ballast KW - Axle impulses PY - 2020 AN - OPUS4-51212 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz T1 - Natural frequencies and modes of poles, beams, floors, road and rail bridges N2 - In the last three decades, the vibrations of many floors and bridges have been measured. The contribution shows some evaluation methods, experimental results and some modelling and theoretical results. Simple evaluation methods have been developed for single and coupled floors. Two coupled beams have been measured in good agreement with the theory. A more complex coupling model has been found for a large wooden floor in a castle consisting of six floor bays which correlates well with the measurements. Damaged and intact poles have been tested by their natural frequencies and damping values, and a fair correlation between the degree of damage and the shift of the frequency. Road bridges have been analysed in detail and some examples are presented. Railway bridges and trains are studied for resonant excitation. The risk of resonance can be estimated in frequency domain by using axle-sequence spectra of the train and the natural frequencies of the bridge. A measurement example shows the amplification, but even stronger the cancellation of the subsequent axle responses. Several high-speed trains and freight trains have been analysed for their potential resonance amplification. T2 - International Conference on Noise and Vibration Engineering (ISMA/USD 2020) CY - Online meeting DA - 07.09.2020 KW - Modalanalyse KW - Bauwerke KW - Bauteile KW - Brücken KW - Achsfolgespektren PY - 2020 AN - OPUS4-51213 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Günther, Martin A1 - Levchik, S. V. A1 - Schartel, Bernhard T1 - Bubbles and collapses: Fire phenomena of flame-retarded flexible polyurethane foams N2 - Flexible polyurethane foams (FPUF) are easy to ignite and exhibit rapid flame spread. In this paper, the fire phenomena of two standard foam formulations containing tris (1,3-dichloro-2-propyl) phosphate (FR-2) and a halogen-freepoly (ethyl ethylene phosphate) (PNX), respectively, as flame retardants are compared. A multimethodological approach is proposed which combines standard fire tests as well as new investigatory approaches. The thermophysical properties of the foams were determined by thermogravimetric analysis (TG), reaction to small flames was studied by means of the limiting oxygen index (LOI) and UL 94 HBF test, and the burning behavior was investigated with the cone calorimeter. Further, temperature development in burning cone calorimeter samples was monitored using thermocouples, and rheological measurements were performed on pyrolyzed material, delivering insight into the dripping behavior of the foams. This paper gives comprehensive insight into the fire phenomena of flame-retarded FPUFs that are driven by the two-step decomposition behavior of the foams. LOI and UL 94 HBF tests showed a reduced flammability and reduced tendency to drip for the flame-retarded foams. TG and cone calorimeter measurements revealed that the two-step decomposition behavior causes two stages during combustion, namely structural collapse and pool fire. The flame-retardant mode of action was identified to take place primarily during the foam collapse and be based mainly on flame inhibition. However, some condensed-phase action was been measured, leading to significantly increased melt viscosity and improved dripping behavior for foams containing PNX. KW - Burning behavior KW - Flame retardant KW - Flexible PU foam PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-512145 DO - https://doi.org/10.1002/pat.4939 SN - 1042-7147 SN - 1099-1581 VL - 31 IS - 10 SP - 2185 EP - 2198 PB - Wiley Online Libary AN - OPUS4-51214 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CHAP A1 - Huismann, Sven A1 - Zeiml, M. A1 - Korzen, Manfred A1 - Millard, A. ED - Millard, A. ED - Pimienta, P. T1 - Engineering Modelling N2 - This chapter presents the most commonly used approach to analyse the thermo-mechanical behaviour of concrete structures subjected to high temperatures as in the case of fire loading. Prescriptions of the Eurocode are detailed for the thermal as well as the mechanical analysis. Finally, recommendations from two national (Austrian and German) guidelines give some improvements for Underground infrastructure. KW - Concrete KW - High temperature KW - Stress-strain-relation PY - 2019 SN - 978-3-030-11995-9 DO - https://doi.org/10.1007/978-3-030-11995-9 SN - 2213-204X SN - 2213-2031 SP - 15 EP - 25 PB - Springer CY - Cham, Switzerland AN - OPUS4-51186 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Bäßler, Ralph T1 - Rezension: Materialkunde der Nichteisenmetalle und ‐legierungen N2 - Die Werkstoffklasse der Nichteisenmetalle gewinnt wegen ihrer unzähligen Anwendungsmöglichkeiten nicht nur im Maschinen‐ und Anlagenbau eine immer größere technische und wirtschaftliche Bedeutung, sodass es unabdingbar ist, insbesondere Studierenden der Material‐ und Werkstoffwissenschaften und des Maschinenbaus, den aktuellen Wissensstand auf diesem Gebiet zu vermitteln. Mit dieser Neuerscheinung veröffentlicht der Wiley‐VCH‐Verlag ein solches Lehrbuch. Kompakt und übersichtlich machen die beiden Autoren den Leser in 10 Kapiteln auf verständliche Art mit dieser Thematik vertraut. Dabei kommt ihnen ihre durch langjährige Lehrtätigkeit erworbene didaktische Erfahrung sehr zugute. Alles in allem bietet dieses Lehrbuch durch seinen von den Natur‐, über Material‐ zu Ingenieurwissenschaften weitgespannten Bogen einen interessanten und übersichtlichen Einstieg in die Welt der am häufigsten verwendeten Nichteisenmetalle, wobei es keinen Anspruch auf Vollständigkeit erhebt. KW - Werkstoffprüfung KW - Legierung KW - Korrosion PY - 2020 DO - https://doi.org/10.1002/maco.202070086 SN - 1521-4176 VL - 71 IS - 8 SP - 4 PB - Wiley‐VCH CY - Weinheim AN - OPUS4-51073 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bäßler, Ralph T1 - Deposition of Brine Components on Materials in Geothermal Conditions T1 - ОСАЖДЕНИЕ КОМПОНЕНТОВ ГЕОТЕРМИЧЕСКИХ ВОД НА МАТЕРИАЛЫ В ГЕОТЕРМАЛЬНЫХ УСЛОВИЯХ N2 - Since geothermal wells are a feasible energy source to replace fossil fuel supply, many technologies have been developed to take advantage of geothermal energy. Nevertheless, service conditions in geothermal facilities are in many cases extreme in terms of corrosion due to the chemical composition of hydrothermal fluids and temperatures. Therefore, materials selection based on preliminary material qualification is essential to guarantee a secure and reliable operation of the facilities. During operation of a geothermal research facility in Groß Schönebeck copper and lead effects have been found downhole. Occurring mechanisms and measures to prevent precipitation or scaling needed to be investigated as well as potential influences of such precipitates on corrosion resistance of metallic materials used for equipment. This contribution deals with the evaluation of the corrosion behavior of carbon steel and corrosion resistant alloys in copper and/or lead containing artificial geothermal water, simulating the conditions in the Northern German Basin. The behavior of these materials in an artificial geothermal water obtained by electrochemical measurements and exposure tests are presented. While carbon steel exhibits precipitation and deposition, higher alloyed material shows different response to such species and a higher resistance in saline geothermal water. Basing on these results the suitability of the investigated corrosion resistant alloy is given for use in such conditions, whereas carbon steel creates difficulties due to its susceptibility to Cu- and Pb-precipitation. N2 - Поскольку геотермальные скважины являются реальным источником энергии для замены поставок ископаемого топлива, было разработано множество технологий для использования преимуществ геотермальной энергии. Тем не менее, условия эксплуатации на геотермальных установках во многих случаях являются экстремальными с точки зрения коррозии из-за химического состава гидротермальных жидкостей и температур. Таким образом, выбор материалов на основе предварительной квалификации имеет важное значение для обеспечения безопасной и надежной работы геотермальных объектов. Во время работы исследовательской установки в Грос Шёнебек (Groß Schönebeck) в скважине было обнаружено воздействие меди и свинца. Необходимо изучить возникшие механизмы и меры для предотвращения депозиции или образования коррозии, а также потенциальное влияние таких осаждений на коррозионную стойкость металлов, используемых для оборудования. Этот доклад посвящен оценке коррозионного поведения углеродистой стали и коррозионно-стойких сплавов в геотермальной воде, содержащей медь и / или свинец, моделирующей условия в Северогерманском бассейне (North German basin). Представлено поведение этих металлических материалов в геотермальной воде, полученной путем электрохимических измерений и испытаний на воздействие. В то время как углеродистая сталь демонстрирует коррозию и отложения, высоколегированный материал демонстрирует более высокую стойкость в соленой геотермальной воде. На основании этих результатов пригодность исследуемого коррозионно-стойкого сплава дана для использования в данных условиях, тогда как углеродистая сталь создает трудности из-за ее восприимчивости к депозиции солей меди и свинца. T2 - ХV International Conference Problems of Corrosion and Corrosion Protection of Materials “CORROSION-2020” CY - Online meeting DA - 15.10.2020 KW - Copper KW - Lead KW - Corrosion KW - Steel KW - Geothermal PY - 2020 UR - http://www.ipm.lviv.ua/corrosion2020/ AN - OPUS4-51438 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Bäßler, Ralph T1 - Review: What Went Wrong? Case Histories of Process Plant Disasters and How They Could Have Been Avoided N2 - Plant and process safety are very important within the daily business not only in industry. Within its 6th edition complete analysis of design, operational, and management causes of process plant accidents and disasters are collected by Paul Amyotte basing on Trevor Kletz's legacy. Examples shall help readers in understanding what went wrong, why it went wrong and how to avoid similar tragedies without having to experience the loss incurred by others and themselves. Each main part ends with an opportunity for reflection to recall the lessons learned from the examples shown. This collection of, unfortunately, spectacular failure cases fulfills its intension of being the ultimate resource of experienced‐based analysis and guidance for safety and loss prevention professionals. Everyone who is dealing with process and/or plant safety shall have taken at least a look into this book. KW - Failure KW - Damage cases PY - 2020 DO - https://doi.org/10.1002/maco.202070124_2 SN - 1521-4176 SN - 0947-5117 VL - 71 IS - 12 SP - 2084 EP - 2085 PB - WILEY‐VCH Verlag GmbH & Co. KGaA CY - Weinheim AN - OPUS4-51781 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Babutzka, Martin T1 - Überarbeitung des GfKORR-Leitfadens „Korrosionsschutz von Offshore-Windenergieanlagen" N2 - Der Vortrag stellt den aktuellen Stand und die Diskussionsthemen für die Überarbeitung des GfKORR-Leitfadens "Korrosionsschutz von Offshore-Windenergieanlagen" vor. T2 - Gemeinsame Sitzung des GfKORR Arbeitskreises „Korrosionsschutz von Windenergieanlagen“ mit der Fachgruppe „Korrosionsschutz“ der WAB e.V. CY - Online meeting DA - 07.12.2020 KW - Leitfaden KW - Korrosionsschutz KW - Offshore-Windenergieanlagen PY - 2020 AN - OPUS4-51784 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Nerger, Deborah A1 - Moosavi, Robabeh A1 - Bracklow, F. A1 - Hering, M. A1 - Kühn, T. A1 - Curbach, M. A1 - Hille, Falk A1 - Rogge, Andreas ED - Papadrakakis, M. ED - Fragiadakis, M. ED - Papadimitriou, C. T1 - Impact damage characterization at RC plates with planar tomography and FEM N2 - Prediction of dynamic effects of reinforced concrete structures under impact loading is a technical challenge. This is a consequence of the great variability of the physical properties resulting from the wide adaptability of reinforced concrete and a consequence of the wide range of impact loading. Experiments and numerical investigations are normally used on a small scale to address the problem. In this paper, impact tests on reinforced conrete plates with the lateral dimensions of 1.5 m x 1.5 m and a thickness of 30 cm are presented. In bending reinforcement, besides the velocity two properties are varied, the diameter and the spatial distribution of the rebars. Experiments are performed at the Otto-Mohr-Laboratory of the Institute of Concrete Structures of the Technische Universit¨at Dresden. Due to the accelerated fall of the impactor the velocity ranges between 20 and 70 m/s. In addition to the measured quantities such as bearing forces, accelerations are also measured at 4 different positions on and under the plate, as well as the deflection at several positions. The measured data are used for the analysis of the damage form and the numerical examinations with the program Ansys Autodyn and the material model after Drucker-Prager. Numerical investigations support the tests, with detailed analysis of individual effects. These numerical computations and the planar tomographic investigations were carried out at BAM in Berlin. With the help of planar tomographic evaluation, the damaged structure is made visible and compared with the numerical results. Influences of the bending reinforcement are explained on the basis of damage evaluation in the local area and on selected measured values. In addition to the test evaluation, the tomographic and numerical methods are presented. T2 - XI International Conference on Structural Dynamics (EURODYN 2020) CY - Online meeting DA - 23.11.2020 KW - Post-impact evaluation KW - Damage characterization KW - Planar tomography KW - Drucker-Prager KW - Ansys Autodyn PY - 2020 SN - 978-618-85072-2-7 VL - 1 SP - 2521 EP - 2543 PB - Institute of Structural Analysis and Antiseismic Research, School of Civil Engineering, National Technical University of Athens (NTUA), Greece CY - Athens, Greece AN - OPUS4-51769 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Bäßler, Ralph T1 - Rezension: Polymere ‐ Chemie und Strukturen; Herstellung, Charakterisierung und Werkstoffe N2 - Polymere sind aus unserem Alltag nicht mehr wegzudenken. Häufig haben wir mit Plexiglas, Dichtmassen, Klebestreifen und vielen Verpackungsmaterialien zu tun. Aber auch Spezialanwendungen (z.B. in der Pharmazie) bilden Einsatzbereiche dieser Werkstoffe. Der Vermittlung der Grundlagen polymerer Werkstoffe in den Studienfächern Chemie, Materialwissenschaften und der Ingenieur‐ und Lebenswissenschaften haben sich die Autoren verschrieben, wobei sie zur verständlichen Anschauung bewusst auf das Beispiel Styrol als „Versuchskaninchen“ zurückgreifen. Dieses Lehrbuch wird seinem Anspruch gerecht, einen leichten Einstieg in die Polymerwissenschaften zu ermöglichen. Es liefert eine Übersicht über die Polymerklassen Thermoplaste, Duroplaste und Elastomere mit ihren Eigenschaften und zeigt, welche Synthesestrategie zu dem Produkt mit den gewünschten Eigenschaften führt. Anhand von Beispielen aus dem Alltag werden gängige Vertreter verständlich vorgestellt. KW - Polymerwerkstoff PY - 2020 DO - https://doi.org/10.1002/maco.202070126 SN - 1521-4176 VL - 71 IS - 12 SP - 2 EP - 3 PB - WILEY‐VCH Verlag GmbH & Co. KGaA CY - Weinheim AN - OPUS4-51777 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Bäßler, Ralph T1 - Rezension: Einführung in die Physikalische Chemie N2 - Unabhängig vom im Chemieunterricht erworbenen Wissensstand der Studienanfänger liefert dieses, in der Reihe „De Gruyter Studium“ erschienene Lehrbuch einen Einstieg in die Physikalische Chemie. Basierend auf den Erfahrungen seiner Lehrtätigkeit für Erstsemester der Fachrichtung Chemie an der Universität des Saarlandes geht der Autor auf beinahe alle Themengebiete der Physikalischen Chemie ein, wobei die Schwerpunkte auf klassischer Thermodynamik und Grundlagen der chemischen Bindung liegen. Dieses Lehrbuch ist nicht nur für Studierende im Bachelorstudium der Chemie sowohl im Haupt‐ als auch im Nebenfach geeignet. Es liefert zudem Interessierten anderer Fachrichtungen einen übersichtlichen und verständlichen Einstieg in die komplexe Welt der Physikalischen Chemie und sorgt für ein Grundverständnis. KW - Elektrochemie PY - 2020 DO - https://doi.org/10.1002/maco.202070126_2 SN - 1521-4176 SN - 0947-5117 VL - 71 IS - 12 SP - 3 EP - 4 PB - WILEY‐VCH Verlag GmbH & Co. KGaA CY - Weinheim AN - OPUS4-51779 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Bäßler, Ralph T1 - Review: Electrochemical Energy Storage ‐ Physics and Chemistry of Batteries N2 - Currently, storage of electric energy is becoming more and more interesting in terms of applicability and efficiency. One way is the electrochemical storage by already well‐developed battery‐systems. This textbook provides an introduction into physical and chemical processes necessary for battery application. This book fulfills its intension to serve graduate students of electrical engineering as an introduction into the field of batteries. Even students and interested readers of other faculties might find an introduction in physical and chemical background of batteries. KW - Batteries PY - 2020 DO - https://doi.org/10.1002/maco.202070124 SN - 1521-4176 SN - 0947-5117 VL - 71 IS - 12 SP - 2084 EP - 2085 PB - WILEY‐VCH Verlag GmbH & Co. KGaA CY - Weinheim AN - OPUS4-51780 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Herrmann, Ralf T1 - Implementing a Structural Health Monitoring System using Digital Models of the BAM Large Drop Test Facility N2 - At the Bundesanstalt für Materialforschung und -prüfung (BAM) full scale specimens for nuclear transport and storage containers (casks) are tested for their structural integrity in a series of drop tests on the Test Site Technical Safety in Horstwalde, 50 km south of Berlin. These drop tests cause a major stress not only on the casks, but also on the steel tower structure of the test facility, itself. The load pattern makes the structure very interesting for detailed investigation. The focus of the monitoring lies on the bolted joints of the flange connections that are a typical connection for cylindrical elements if welding is technical or economical unfavorable. The definition of the monitoring takes was done by investigating the existing documents and inspection results accompanied by building an initial digital representation of the structure, consisting of two finite element (FE) models and a geometrical 3D point cloud representation. As a first step the structures behavior during static and dynamic loading was analyzed using measurement data and an updated numerical FE Model. The idea behind is to use models for a digital planning and operation/evaluation of the structural health monitoring. A static FE simulation and a dynamic FE simulation are generated, to investigate how the structure behaves under the load conditions. T2 - XI International Conference on Structural Dynamics (EuroDyn 2020) CY - Online meeting DA - 23.11.2020 KW - Structural Health Monitoring KW - System Identification KW - Digital Twin KW - Point Cloud KW - Drop Test PY - 2020 AN - OPUS4-51734 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - von Werder, Julia A1 - Gardei, André A1 - Hoppe, Johannes A1 - Meng, Birgit ED - Littmann, K. T1 - Funktionalisierung von Fasern für zementgebundene Materialien - ausgewählte Prüfmethoden N2 - Die geringe Zugfestigkeit von zementgebundenen Materialien kann durch die Zugabe von Fasern maßgeblich verbessert werden. Ziel eines gemeinsamen Verbundprojekts mit einem Industriepartner war die Erhöhung der Leistungsfähigkeit von kurzen Polymer- und Carbonfasern durch eine Verbesserung des Verbundes zwischen Faseroberfläche und Zementsteinmatrix. Von der IONYS AG wurde dazu eine spezielle Funktionalisierung entwickelt, die über eine Hydrophilisierung der Faseroberfläche eine chemische Anbindung an die Zementsteinmatrix gewährleistet. Aufgabe der BAM war es, die Effizienz der neuen Beschichtung bezüglich der Erhöhung der Nachrissbiegezugfestigkeit und der Reduzierung der Schwindrissbildung während der Erhärtungsphase zu quantifizieren. Die Ergebnisse zeigen, dass die Funktionalisierung die Neigung zur Schwindrissbildung für die Carbonfasern und in noch stärkerem Maße für die Polymerfasern reduziert. Eine Erhöhung der Nachrissbiegezugfestigkeit konnte dagegen nur für die deutlich steiferen Carbonfasern nachgewiesen werden. T2 - 10. Kolloquium Industrieböden CY - Esslingen, Germany DA - 03.03.2020 KW - Fibres KW - Cementitious materials KW - Shrinkage KW - Strain hardening PY - 2020 SN - 978-3-8169-3505-6 SP - 173 EP - 178 PB - expert Verlag GmbH CY - Tübingen AN - OPUS4-51915 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Goedecke, Caroline A1 - Dittmann, Daniel A1 - Eisentraut, Paul A1 - Wiesner, Yosri A1 - Schartel, Bernhard A1 - Klack, Patrick A1 - Braun, Ulrike T1 - Evaluation of thermoanalytical methods equipped with evolved gas analysis for the detection of microplastic in environmental samples N2 - Microplastic particles are currently detected in almost all environmental compartments. The results of detection vary widely, as a multitude of very different methods are used with very different requirements for analytical validity. In this work four thermoanalytical methods are compared and their advantages and limitations are discussed. One of them is thermal extraction-desorption gas chromatography mass spectrometry (TED-GC/MS), an analysis method for microplastic detection that has become established in recent years. In addition, thermogravimetric analysis coupled with Fourier-transform infrared spectroscopy (TGA-FTIR) and mass spectrometry (TGA-MS) were applied, two methods that are less common in this field but are still used in other research areas. Finally, microscale combustion calorimeter (MCC) was applied, a method not yet used for microplastic detection. The presented results are taken from a recently published interlaboratory comparison test by Becker et al. (2020). Here a reference material consisting of suspended matter and specified added polymer masses was examined, and only the results of the recoveries were presented. In the present paper, however, the results for the individual polymers are discussed in detail and individual perspectives for all instruments are shown. It was found that TED-GC/MS is the most suitable method for samples with unknown matrix and unknown, variable kinds and contents of microplastic. TGA-FTIR is a robust method for samples with known matrix and with defined kinds of microplastic. TGA-MS may offer a solution for the detection of PVC particles in the future. MCC can be used as a very fast and simple screening method for the identification of a potential microplastic load of standard polymers in unknown samples. KW - Microplastic KW - TED-GC/MS KW - TGA-MS KW - TGA-FTIR KW - MCC KW - Thermal analysis PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-516687 DO - https://doi.org/10.1016/j.jaap.2020.104961 VL - 152 SP - 104961 PB - Elsevier B.V. AN - OPUS4-51668 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz A1 - Ziemens, Susanne T1 - The response of different buildings to free-field excitation – a study using detailed finite element models N2 - A study on building vibrations has been performed by finite element calculations. Family houses, multi-storey residential buildings, office buildings and office towers have been modelled in detail. The frequency-dependent response due to a free-field excitation has been evaluated for walls, columns and floors. The ratio of building amplitudes to free-field amplitudes starts with uB/u0 = 1 at zero frequency and is usually lower than 1 at 50 Hz, the end of the frequency range considered here. In between, amplifications occur due to several reasons. There are „soil resonances“ where the whole building is vibrating on the compliant soil, “column resonances” where the upper storeys are vibrating on the compliant columns, and the “floor resonances” where the floors are vibrating excited by their supports. Results are presented for all building types, but a special focus is set on office buildings. A parameter study shows the influence of the stiffness of the soil, the number of storeys, and the width of the building. It has been found that the “soil resonance” is strongly modified by the low-frequency floor resonances for the normal office building. The main resonance of a twenty-storey office tower is determined equally by the “soil mode” and the “column mode”. It is an important observation for these office buildings that the resonances can differ for different parts of the building such as the centre, the edge, the corner, and the core of the building. This leads to non-uniform vibration modes across the building, which look like another type of “floor resonance” and which have been observed in several real building projects. Experimental results will be shown which can confirm the calculated phenomena. T2 - EURODYN 2020 XI International Conference on Structural Dynamics CY - Online meeting DA - 13.11.2020 KW - Building vibration KW - Office building KW - Residential building KW - Soil-building resonance KW - Floor resonance KW - Column/wall resonance PY - 2020 SN - 978-618-85072-2-7 SP - 4560 EP - 4576 CY - Athen AN - OPUS4-51678 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz T1 - The response of different buildings to free-field excitation – a study using detailed finite element models N2 - A study on building vibrations has been performed by finite element calculations. Family houses, multi-storey residential buildings, office buildings and office towers have been modelled in detail. The frequency-dependent response due to a free-field excitation has been evaluated for walls, columns and floors. The ratio of building amplitudes to free-field amplitudes starts with uB/u0 = 1 at zero frequency and is usually lower than 1 at 50 Hz, the end of the frequency range considered here. In between, amplifications occur due to several reasons. There are „soil resonances“ where the whole building is vibrating on the compliant soil, “column resonances” where the upper storeys are vibrating on the compliant columns, and the “floor resonances” where the floors are vibrating excited by their supports. Results are presented for all building types, but a special focus is set on office buildings. A parameter study shows the influence of the stiffness of the soil, the number of storeys, and the width of the building. It has been found that the “soil resonance” is strongly modified by the low-frequency floor resonances for the normal office building. The main resonance of a twenty-storey office tower is determined equally by the “soil mode” and the “column mode”. It is an important observation for these office buildings that the resonances can differ for different parts of the building such as the centre, the edge, the corner, and the core of the building. This leads to non-uniform vibration modes across the building, which look like another type of “floor resonance” and which have been observed in several real building projects. Experimental results will be shown which can confirm the calculated phenomena. T2 - EURODYN 2020 XI International Conference on Structural Dynamics CY - Online meeting DA - 23.11.2020 KW - Building vibration PY - 2020 AN - OPUS4-51679 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Gleuwitz, F. Robert T1 - Non-vegan flame retardant biocomposites N2 - Products and by-products of the invertebrate and vertebrate farming, respectively, are shown to be promising bio-based flame retardant adjuvants in epoxy thermosets. While the addition of bone meal results in the formation of an inorganic shield, protein-based powders from insects provide an intumescent behavior under forced flaming conditions. Combining the latter with a common flame retardant such as ethylene diamine phosphate, the charring efficiency and self-extinguishing properties can be further enhanced. T2 - 18th European Meeting on Fire Retardant Polymeric Materials, FRPM21 CY - Budapest, Hungary DA - 29.08.2021 KW - Bio-based KW - Insects KW - Epoxy KW - Intumescence KW - Flame retardancy PY - 2021 AN - OPUS4-53219 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz T1 - Zur Prognose von Erschütterungen aus Bahntunneln N2 - Zur Erschütterungsausbreitung an oberirdischen Bahnlinien gibt es gute Übereinstimmungen zwischen Messungen und der Theorie geschichteter Böden. Bei der Interpretation der Ergebnisse spielt die Rayleigh-Welle eine große Rolle. Je nach Frequenz und Wellenlänge hat die Rayleigh-Welle eine bestimmte Eindringtiefe und erreicht damit mehr oder weniger steife Bodenschichten. Damit bekommt man eine frequenzabhängige Bodensteifigkeit für die Erschütterungsprognose. Für die Wellenausbreitung in der Tiefe statt an der Bodenoberfläche müssen eigene Gesetzmäßigkeiten gefunden werden. Es werden die Punktlastlösungen im Frequenz-Wellenzahlbereich und durch Integration über die Wellenzahlen berechnet. Man erhält die Wellenfelder, die Terzspektren für verschiedene Entfernungen und Frequenzen. Es wird die Tiefenlage und das Bodenmodell (homogen, geschichtet und kontinuierlich zunehmende Steifigkeit) variiert. Die Rayleigh-Welle verliert ihre Bedeutung und stattdessen kann die Vollraumlösung zur Interpretation und Prognose verwendet werden. Es werden die Halbraumlösung mit und ohne Rayleigh-Welle und die Vollraumlösung in der Tiefe diskutiert und verglichen. Neben der Wellenausbreitung (der Transmission) werden auch Effekte der Erschütterungsanregung (der Emission) und der Übertragung in Gebäude (der Immission) mit Hilfe der Finite-Element-Randelement-Methode berechnet. Die Verteilung der dynamischen Achslast durch die Tunnelsohle ergibt eine Minderung gegenüber der Punktlastanregung. Bei der Immission hat man keine Freifeldanregung wie an der Bodenoberfläche. Man muss entweder neben der Wellenamplitude (Verschiebung oder Schwinggeschwindigkeit) in der Tiefe auch die Spannung der ankommenden Welle berücksichtigen, oder man muss die Freifeldamplituden nach Bodenaushub berechnen. Die Rechenergebnisse deuten darauf hin, dass man als Freifeldanregung die zweifache Vollraumlösung ansetzen kann. T2 - Wiener Dynamik Tage 2021 CY - Vienna, Austria DA - 22.7.2021 KW - Erschütterungsausbreitung KW - Tunnel KW - Halbraum KW - Vollraum PY - 2021 SP - 1 EP - 11 PB - Steinhauser Consulting Engineers (STCE) CY - Wien AN - OPUS4-53253 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Battig, Alexander A1 - Sanchez-Olivares, G. A1 - Rockel, Daniel A1 - Maldonado-Santoyo, M. A1 - Schartel, Bernhard T1 - Waste not, want not: The use of leather waste in flame retarded EVA N2 - Leather is among the most ancient, widely used materials worldwide. Industrial-scale leather production produces large quantities of organic waste attained during shaving and buffing steps during processing. In this study, leather wastes (LW) are used as fillers in flame retarded polymer composites. LW is investigated as a multifunctional bio-filler that enhances the fire performance of flame retarded poly(ethylene–vinyl acetate) (EVA) containing phosphorus flame retardants (P-FRs) ammonium polyphosphate (APP) or a melamine-encapsulated APP (eAPP). Using LW from tanneries as adjuvants to enhance P-FRs in EVA reduces industrial wastes that otherwise require costly waste management solutions. Materials are characterized multi-methodically via mechanical tests, electron microscopy, rheology, thermogravimetric analysis, evolved gas analysis, and condensed phase FTIR, also reaction-to-small-flames and cone calorimeter tests. EVA containing 10 wt-% LW and 20 wt-% P-FRs achieve 20% reductions in fire loads versus EVA, and up to 10% reduction in effective heats of combustion versus EVA with equal (30 wt-%) P-FR loadings. Enhanced char stabilization of EVA composites with LW and P-FRs lowered peaks of heat release rates up to 53% compared to EVA, and up to 40% compared to equal P-FRs loadings. Synergisms between LW and P-FRs in EVA are quantified. A chemical decomposition mechanism is proposed. KW - Leather waste KW - Tannery industry KW - EVA KW - Fire protection KW - Flame retardancy KW - Charring PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-532977 DO - https://doi.org/10.1016/j.matdes.2021.110100 SN - 0264-1275 VL - 210 SP - 1 EP - 16 PB - Elsevier CY - Amsterdam AN - OPUS4-53297 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Seher, Julia A1 - Fröba, M. T1 - Shape matters: The effect of particle morphology on the fast-charging performance of LiFePO4/C nanoparticle composite electrodes N2 - For the successful use of lithium-ion batteries in automotive applications, reliable availability of high storage capacity and very short recharging times are essential. In order to develop the perfect battery for a certain application, structure–property relationships of each active material must be fully understood. LiFePO4 is of great interest due to its fast-charging capability and high stability regarding its thermal resistance and chemical reactivity. The anisotropic lithium-ion diffusion through the LiFePO4 crystal structure indicates a strong dependence of the electrochemical performance of a nanostructured active material on particle morphology. In this paper, the relationship of the particle morphology and fast-charging capability of LiFePO4/C core/shell nanoparticles in half-cells was studied. For this purpose, a new multistep synthesis strategy was developed. It involves the combination of a solvothermal synthesis followed by an in situ polymer coating and thermal calcination step. Monodisperse rodlike LiFePO4 nanoparticles with comparable elongation along the b-axis (30–50 nm) and a varying aspect ratio c/a (2.4–6.9) were obtained. A strong correlation of the fast-charging capability with the aspect ratio c/a was observed. When using LiFePO4 nanoparticles with the smallest aspect ratio c/a, the best electrochemical performance was received regarding the specific capacity at high C-rates and the cycling stability. A reduction of the aspect ratio c/a by 30% (3.6 to 2.4) was found to enhance the charge capacity at 10 C up to an order of magnitude (7.4–73 mA h·g–1). KW - LiFePO4 KW - Schnellladung KW - Nanoparticles KW - Carbon KW - Chemical synthesis KW - Electrochemical cells KW - Materials PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-533004 DO - https://doi.org/10.1021/acsomega.1c03432 SN - 2470-1343 VL - 6 IS - 37 SP - 24062 EP - 24069 PB - American Chemical Society CY - Washington, DC AN - OPUS4-53300 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz T1 - Zur Prognose von Erschütterungen aus Bahntunneln N2 - Zur Erschütterungsausbreitung an oberirdischen Bahnlinien gibt es gute Übereinstimmungen zwischen Messungen und der Theorie geschichteter Böden. Bei der Interpretation der Ergebnisse spielt die Rayleigh-Welle eine große Rolle. Je nach Frequenz und Wellenlänge hat die Rayleigh-Welle eine bestimmte Eindringtiefe und erreicht damit mehr oder weniger steife Bodenschichten. Damit bekommt man eine frequenzabhängige Bodensteifigkeit für die Erschütterungsprognose. Für die Wellenausbreitung in der Tiefe statt an der Bodenoberfläche müssen eigene Gesetzmäßigkeiten gefunden werden. Es werden die Punktlastlösungen im Frequenz-Wellenzahlbereich und durch Integration über die Wellenzahlen berechnet. Man erhält die Wellenfelder, die Terzspektren für verschiedene Entfernungen und Frequenzen. Es wird die Tiefenlage und das Bodenmodell (homogen, geschichtet und kontinuierlich zunehmende Steifigkeit) variiert. Die Rayleigh-Welle verliert ihre Bedeutung und stattdessen kann die Vollraumlösung zur Interpretation und Prognose verwendet werden. Es werden die Halbraumlösung mit und ohne Rayleigh-Welle und die Vollraumlösung in der Tiefe diskutiert und verglichen. Neben der Wellenausbreitung (der Transmission) werden auch Effekte der Erschütterungsanregung (der Emission) und der Übertragung in Gebäude (der Immission) mit Hilfe der Finite-Element-Randelement-Methode berechnet. Die Verteilung der dynamischen Achslast durch die Tunnelsohle ergibt eine Minderung gegenüber der Punktlastanregung. Bei der Immission hat man keine Freifeldanregung wie an der Bodenoberfläche. Man muss entweder neben der Wellenamplitude (Verschiebung oder Schwinggeschwindigkeit) in der Tiefe auch die Spannung der ankommenden Welle berücksichtigen, oder man muss die Freifeldamplituden nach Bodenaushub berechnen. Die Rechenergebnisse deuten darauf hin, dass man als Freifeldanregung die zweifache Vollraumlösung ansetzen kann. T2 - Wiener Dynamik Tage 2021 CY - Vienna, Austria DA - 22.07.2021 KW - Erschütterungsausbreitung KW - Tunnel KW - Halbraum KW - Vollraum PY - 2021 AN - OPUS4-53254 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz ED - Carletti, E. ED - Crocker, M. ED - Pawelczyk, M. ED - Tuma, J. T1 - Dynamic measurements during drop tests on stiff foundations N2 - Measurements at the foundation, the surrounding soil and nearby buildings have been done during several drop tests of different containers on different foundations. The first measurements have been done on a big foundation where it should be guaranteed that the foundation is rigid and the container is tested properly. It was controlled that the foundation does not absorb more than 2 percent of the energy of the container. Most of the drop energy is lost in shock absorbers. Later on, a smaller drop test facility has been built on the ground but inside an existing building. It had to be controlled by prediction and measurements that the drop test will not damage the building. Tests from different heights on soft, medium, and stiff targets have been done to find out rules which allow to identify acceptable and unacceptable drop tests. Later on, the biggest drop test facility has been built for masses up to 200 t. It was necessary for the design of the foundation to estimate the forces which occur during the drop tests. On the other hand, the acceptable tests should be selected and controlled by measurements where the impact duration is important. Different sensors, accelerometers, accelerometers with mechanical filters, geophones (velocity transducers), strain gauges, and pressure cells have been applied for these tasks. The signals have been transformed to displacements which proved to be best suited for the interpretation of the impact mechanism. Modell calculations have been used to check and understand the dynamic measurements. The simplest law is the conservation of the momentum which is a good approximation if the impact is short. If the soil under the foundation has an influence on the deceleration of the container, the maximum foundation velocity is lower than the simple estimation. The amplitudes of the foundation could also be estimated from the ground vibrations and their amplitude-distance law. T2 - 27th International Congress on Sound and Vibration (ICSV27) CY - Online meeting DA - 11.07.2021 KW - Drop test KW - Vibration measurement KW - Container loading KW - Foundation load PY - 2021 SN - 978-83-7880-799-5 SN - 2329-3675 SP - 1 EP - 8 PB - Silesian University Press CY - Gliwice, Poland AN - OPUS4-53255 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz T1 - Dynamic measurements during drop tests on stiff foundations N2 - Measurements at the foundation, the surrounding soil and nearby buildings have been done during several drop tests of different containers on different foundations. The first measurements have been done on a big foundation where it should be guaranteed that the foundation is rigid and the container is tested properly. It was controlled that the foundation does not absorb more than 2 percent of the energy of the container. Most of the drop energy is lost in shock absorbers. Later on, a smaller drop test facility has been built on the ground but inside an existing building. It had to be controlled by prediction and measurements that the drop test will not damage the building. Tests from different heights on soft, medium, and stiff targets have been done to find out rules which allow to identify acceptable and unacceptable drop tests. Later on, the biggest drop test facility has been built for masses up to 200 t. It was necessary for the design of the foundation to estimate the forces which occur during the drop tests. On the other hand, the acceptable tests should be selected and controlled by measurements where the impact duration is important. Different sensors, accelerometers, accelerometers with mechanical filters, geophones (velocity transducers), strain gauges, and pressure cells have been applied for these tasks. The signals have been transformed to displacements which proved to be best suited for the interpretation of the impact mechanism. Modell calculations have been used to check and understand the dynamic measurements. The simplest law is the conservation of the momentum which is a good approximation if the impact is short. If the soil under the foundation has an influence on the deceleration of the container, the maximum foundation velocity is lower than the simple estimation. The amplitudes of the foundation could also be estimated from the ground vibrations and their amplitude-distance law. T2 - 27th international Congress on Sound and Vibration (ICSV27) CY - Online meeting DA - 11.07.2021 KW - Drop test KW - Vibration measurement KW - Container loading KW - Foundation load PY - 2021 AN - OPUS4-53256 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz T1 - Aspekte der Erschütterungsprognose bei Bahnlinien: Quasi-Statik und Achsfolge, unregelmäßiger Schotter und Boden, Wellenausbreitung bei Tunneln und Besonderheiten bei Bürogebäuden N2 - Erschütterungen, die durch Eisenbahnverkehr erzeugt werden, breiten sich durch den Erdboden aus und regen benachbarte Gebäude zu Schwingungen an. Es wurde ein Prognoseverfahren für Bahnerschütterungen ent-wickelt, das mit einfachen Modellen schnell Ergebnisse liefert. Dies sind physikalische Modelle, zum Beispiel 1-dimensionale Modelle mit Übertragungsmatrizen für die Fahrzeug-Fahrweg-Boden-Wechselwirkung und für die Gebäude-Boden Wechselwirkung. Damit werden die komplexen Verhältnisse bei der Emission (dem Zusammen¬wirken von Fahrzeug und Fahrweg), bei der Transmission durch den homogenen oder geschichteten Boden und bei der Immission in Gebäuden näherungsweise erfasst. In (Auersch, 2020) wird gezeigt, dass diese einfachen Prognosemodelle die Ergebnisse von detaillierten Modellen wie der Finite-Element-Randelement-Methode für das Gleis, die Wellenzahlintegrale für den Boden und 3-dimensionale Finite-Element-Modelle für das Gebäude gut wiedergeben können. Dies entspricht auch der Absicht, die Prognosemodelle aus den Ergebnissen der Detailmodelle abzuleiten. Die drei Prognoseteile werden getrennt berechnet, aber es werden physikalisch sinn¬volle Schnittstellen verwendet. Für die Emission und Transmission sind es die auf den Untergrund wirkenden Erregerkräfte von Fahrzeug und Fahrweg, für die Transmission und Immission sind es die Freifeldamplituden des Bodens. T2 - 17. D-A-CH Tagung Erdbebeningenieurwesen und Baudynamik CY - Online meeting DA - 16.09.2021 KW - Erschütterungen KW - Emission KW - Transmission KW - Immission PY - 2021 SP - 17 EP - 18 PB - ETH Zürich CY - Zürich AN - OPUS4-53313 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz T1 - Aspekte der Erschütterungsprognose bei Bahnlinien: Quasi-Statik und Achsfolge, unregelmäßiger Schotter und Boden, Wellenausbreitung bei Tunneln und Besonderheiten bei Bürogebäuden N2 - Erschütterungen, die durch Eisenbahnverkehr erzeugt werden, breiten sich durch den Erdboden aus und regen benachbarte Gebäude zu Schwingungen an. Es wurde ein Prognoseverfahren für Bahnerschütterungen ent-wickelt, das mit einfachen Modellen schnell Ergebnisse liefert. Dies sind physikalische Modelle, zum Beispiel 1-dimensionale Modelle mit Übertragungsmatrizen für die Fahrzeug-Fahrweg-Boden-Wechselwirkung und für die Gebäude-Boden Wechselwirkung. Damit werden die komplexen Verhältnisse bei der Emission (dem Zusammen¬wirken von Fahrzeug und Fahrweg), bei der Transmission durch den homogenen oder geschichteten Boden und bei der Immission in Gebäuden näherungsweise erfasst. In (Auersch, 2020) wird gezeigt, dass diese einfachen Prognosemodelle die Ergebnisse von detaillierten Modellen wie der Finite-Element-Randelement-Methode für das Gleis, die Wellenzahlintegrale für den Boden und 3-dimensionale Finite-Element-Modelle für das Gebäude gut wiedergeben können. Dies entspricht auch der Absicht, die Prognosemodelle aus den Ergebnissen der Detailmodelle abzuleiten. Die drei Prognoseteile werden getrennt berechnet, aber es werden physikalisch sinn¬volle Schnittstellen verwendet. Für die Emission und Transmission sind es die auf den Untergrund wirkenden Erregerkräfte von Fahrzeug und Fahrweg, für die Transmission und Immission sind es die Freifeldamplituden des Bodens. T2 - 17. D-A-CH-Tagung Erdbebeningenieurwesen und Baudynamik CY - Online meeting DA - 16.09.2021 KW - Erschütterungen KW - Emission KW - Transmission KW - Immission PY - 2021 AN - OPUS4-53314 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Erning, Johann Wilhelm T1 - Risikobewertung in der Trinkwasserinstallation N2 - Die Methode zur bewertung und Vermeidung von Risiken beim Betrieb der Trinkwasserinstallation wird dargestellt. Die vorgaben aus Gesetz, Regelwerk und anderen Vorschriften werden erläutert. Die grundsätzliche Philosophie der Vorgehensweise wird beschrieben. T2 - Drei-Länder-Korrosionstagung: Korrosion in der Infrastruktur CY - Online meeting DA - 28.10.2021 KW - Korrosion KW - Trinkwasser-Installation KW - Hygiene KW - Risikobewertung PY - 2021 AN - OPUS4-53655 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Tan, Yi A1 - Wachtendorf, Volker A1 - Kukofka, Tobias A1 - Klack, Patrick A1 - Ruder, J. A1 - Lin, Xuebao A1 - Schartel, Bernhard T1 - Degradation of flame retardance: A comparison of ethylene‐vinyl acetate and low‐density polyethylene cables with two different metal hydroxides N2 - The durability of flame retardancy is a challenge for cables over long lifetimes. The degradation of flame retardance is investigated in two kinds of exposures, artificial weathering and humidity. In this basic study, typical mineral flame retardants in two polymers frequently used in cable jackets are investigated to get the fundamental picture. Aluminum hydroxide (ATH) and magnesium hydroxide (MDH) are compared in ethylene‐vinyl acetate (EVA), and further in EVA and linear low‐density polyethylene (LLDPE) cables containing the same ATH. The changes in chemical structure at the surface are studied through attenuated total reflectance Fourier transform infrared spectroscopy (ATR‐FTIR), the formation of cracks, and changes in color are investigated. The cone calorimeter and a bench scale fire testing cable module are utilized to evaluate the fire behavior of the cables. Although the flame retardancy deteriorated slightly, it survived harsh exposure conditions for 2000 h. Compared to EVA/MDH and LLDPE/ATH, the fire behavior of EVA/ATH is the least sensitive. Taken together, all of the results converge to estimate that there will be no problem with flame retardancy performance, for materials subjected to natural exposure for several years; the durability of fire retardancy is questionable for longer periods, and thus requires further investigation. KW - Durability KW - Flame retardant KW - Aluminum hydroxide (ATH) KW - Magnesium hydroxide KW - Ethylene-vinyl acetate KW - Cables KW - Weathering PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-519573 DO - https://doi.org/10.1002/app.50149 VL - 138 IS - 14 SP - 50149 PB - Wiley AN - OPUS4-51957 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Eberwein, Robert T1 - Untersuchung der Gefährdung von Personen und Bauwerken in Folge des Versagens von LNG-Kraftstoffspeichern für Fahrzeuge in Tunneln N2 - Der Markt von LNG als Transportgut und als Kraftstoff ist seit Jahrzehnten kontinuierlich am Wachsen, wobei das Hauptanwendungsgebiet im Schiffsverkehr lag. LNG ist verflüssigtes Erdgas mit Hauptbestandteil Methan, das neben fossilen, aus erneuerbaren Quellen, wie synthetischen Methan oder Biogas, gewonnen werden kann. LNG hat als Kraftstoff sehr gute Eigenschaften dessen Potenzial als alternativer Kraftstoff zu Diesel im Schwerlast- und Fernverkehr gesehen wird. Dabei weist LNG gegenüber Diesel geringere Emissionen von CO2, Feinstaub, Stickoxiden und Lärm auf und hat gegenüber anderen erneuerbaren Energiespeichern wie CNG, Elektrobatterien oder Wasserstoff die höchste volumetrische und zweitgrößte gravimetrische Energiedichte. Neben seinen Vorteilen zu anderen erneuerbaren Energieträgern birgt LNG durch seine sehr niedrige Temperatur von bis zu 160°C und seiner Brennbarkeit aber auch neue Gefahren für Personen und Infrastrukturen. Zur Bewertung von Gefahren und zur späteren Durchführung von Risikobewertungen bedarf es Methoden und Modellen deren Untersuchung Ziel des Forschungsprojekts war. Schwerpunkt der Untersuchung stellt die Freisetzung von LNG in Tunnel, mit sich anschließender Stoffausbreitung und verzögerter Zündung des Kraftstoff-Luftgemisches dar. Unfallszenarien mit Brandereignissen in Tunnel haben gezeigt, dass diese meist mit hohen Personen, Bauwerks und volkswirtschaftlichen Schäden verbunden sind. Des Weiteren zeigten Untersuchungen das von Gasexplosionen in Umschließungen wie sie ein Tunnel darstellt, mehr Gefahren ausgehen als von Gasexplosionen im Freifeld. Im Vortrag werden die untersuchten Modelle und die aus dem Projekt gewonnenen Erkenntnisse für die Stoffausbreitung und Verbrennung der Gasphase von LNG in Umschließungen vorgestellt. T2 - Abteilungs-Vortragsseminar-Doktoranden CY - BAM Berlin, Germany DA - 08.12.2020 KW - LNG KW - Erdgas KW - Störfall KW - CFD KW - Schwergas PY - 2020 AN - OPUS4-51959 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Daus, Lars-Hendrik A1 - Schartel, Bernhard A1 - Wachtendorf, Volker A1 - Mangelsdorf, R. A1 - Korzen, Manfred T1 - A chain is no stronger than its weakest link: Weathering resistance of water-based intumescent coatings for steel applications N2 - A systematic approach was used to investigate the weathering-induced degradation of a common water–based intumescent coating. In this study, the coatings are intended for humid indoor applications on steel substrates. The coating contains ammonium polyphosphate, pentaerythritol, melamine, and polyvinyl acetate. By replacing each ingredient with a less water-soluble substance, the most vulnerable substances, polyvinyl acetate and pentaerythritol, were identified. Furthermore, the weathering resistance of the system was improved by exchanging the ingredients. The coatings were stressed by artificial weathering tests and evaluated by fire tests. Thermogravimetry and Fourier-transform infrared spectroscopy were used to study the thermal decomposition. This study lays the foundation for the development of a new generation of water-based intumescent coatings. KW - Intumescence KW - Fire resistance KW - Fire protective coatings KW - Weathering KW - Thermogravimetric analyses PY - 2021 DO - https://doi.org/10.1177/0734904120961064 SN - 0734-9041 SN - 1530-8049 VL - 39 IS - 1 SP - 72 EP - 102 PB - SAGE AN - OPUS4-52015 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - von Werder, Julia A1 - Fontana, P. A1 - Hoppe, Johannes A1 - Bilgin, S. A1 - Meng, Birgit ED - Serrat, C. ED - Casas, J. R. ED - Gibert, V. T1 - Composite Facade Elements with Self-Cleaning Surface made of Ultra-High-Performance Concrete (UHPC) N2 - In the framework of the European project H-House various concrete façade elements were developed with the aim to ensure a long service life by combining a very durable material with self-cleaning properties. The façade elements presented are made of a shell of UHPC filled with blocks of aerated autoclaved concrete as insulating material. Self-cleaning properties were realized amongst others by imprinting a microstructure into the surface during casting. The paper focuses on selected technological aspects of the manufacturing process of prototypes which had to be performed in two concreting sections. Furthermore the challenges faced when upscaling the self-cleaning properties are addressed and the strategy to assess the self-cleaning properties by measuring the contact and the roll-off angel is presented. The results show that a successfull upscalaing process requires detailed planning and that the best results can often be achieved with a moderate work effort or material use. T2 - XV International Conference on Durability of Building Materials and Components (DBMC 2020) CY - Online meeting DA - 20.10.2020 KW - Ultra-High-Performance Concrete KW - Facade Elements KW - Self-Cleaning Properties KW - Adhesive Pull-Strength KW - Microstructure KW - Architectural Concrete PY - 2020 SN - 978-84-121101-8-0 SP - 1289 EP - 1297 PB - International Center for Numerical Methods in Engineering (CIMNE) CY - Spain AN - OPUS4-51967 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Auersch, Lutz T1 - Train-induced ground vibration due to the irregularities of the soil N2 - Many measurements of train induced ground vibrations show high amplitudes for a certain mid-frequency range. This ground vibration component cannot be well explained by dynamic loads of the train. Many characteristics indicate that the axle impulses, which are scattered by an irregular soil, are the excitation. This new understanding of railway-induced ground vibration is verified by numerical analysis. The response of the regular homogeneous and irregular inhomogeneous soils has been calculated by the finite-element method in frequency domain. A specific superposition of the impulse responses has been invented including time shift, axle sequence, track filter and hanning filter. The superposition yields the quasi-static component of the ground vibration which is restricted to very low frequencies and to the close near-field of the track. In case of an irregular soil of which the stiffness varies randomly in space, the superposition yields a mid-frequency ground vibration component from the scattering of the axle impulses. The existence and the importance of this component can thus be demonstrated by the calculations. Some rules of the influence of distance, train speed, soil stiffness, strength and width of the stiffness variation have been derived from the calculations. Many measurements show the unique explanation of the mid-frequency ground vibration component by the scattered axle impulses. KW - Train-induced ground vibration KW - Static axle loads KW - Quasi-static response; KW - Axle impulses KW - Irregular soil KW - Random stiffness variation KW - Scattered axle impulses PY - 2021 DO - https://doi.org/10.1016/j.soildyn.2020.106438 SN - 0267-7261 VL - 140 SP - 106438 PB - Elsevier Ltd. CY - London AN - OPUS4-52006 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Fürst, Richard A1 - Mózer, V. A1 - Pokorný, M. A1 - Vlach, T. T1 - Nosné konstrukce z textilního betonu za zvýšené teploty T1 - Loadbearing structures made from textile reinforced concrete at elevated temperatures N2 - The work aims to assess the textile reinforced concrete at elevated temperatures and applications of additional fire protection as well. T2 - Fire Protection Conference CY - Ostrava, Czechia DA - 01.09.2021 KW - High Performance Concrete KW - Textile reinforcement KW - Fire test PY - 2021 SN - 978-80-7385-247-4 SP - 10 EP - 12 PB - Sdružení požárního a bezpečnostního inženýrství CY - Ostrava AN - OPUS4-53509 LA - ces AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Fürst, Richard T1 - Nosné konstrukce z textilního betonu za zvýšené teploty T1 - Loadbearing structures made from textile reinforced concrete at elevated temperatures N2 - The work aims to assess the textile reinforced concrete at elevated temperatures and applications of additional fire protection as well. T2 - Fire Protection Conference CY - Ostrava, Czech Republic DA - 01.09.2021 KW - Fire test KW - High Performance Concrete KW - Textile reinforcement PY - 2021 AN - OPUS4-53510 LA - ces AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Erning, Johann Wilhelm T1 - Corrosion of 1.4521 Pipes in drinking water N2 - Pipes for drinking water made from 1.4521 showed unexpected crevice corosion. The presentation shows the reasons for this damage T2 - Eurocorr 2021 CY - Online meeting DA - 20.09.2021 KW - Crevice corrosion KW - Drinking water KW - Failure analysis PY - 2021 AN - OPUS4-53516 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Erning, Johann Wilhelm T1 - Crevice corrosion in pressed stainless steel pipes: A case study N2 - The completion of a failure analysis for leakages on stainless steel pipes is demonstrated. The steps necessary are describd, the reasons for the failure are shown. T2 - MTech 2021 CY - Sibenik, Croatia DA - 6.10.2021 KW - Failure analysis KW - Stainless steel KW - Drinking water KW - Corrosion PY - 2021 AN - OPUS4-53517 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Erning, Johann Wilhelm T1 - Planung und Betrieb von Trinkwasserinstallationen: Was uns das Regelwerk sagt N2 - Die gesetzlichen und technischen Regeln für Planung, Bau und Betrieb einer Trinkwasserinstallation werden dargestellt. Beispiele für einzelne Punkte werden gegeben. T2 - Der sichere Einsatz von Werkstoffen aus Kupfer und Kupferlegierungen in der Trinkwasserinstallation CY - Online meeting DA - 12.10.2021 KW - Hygiene KW - Korrosion KW - Trinkwasser KW - Werkstoffe PY - 2021 AN - OPUS4-53519 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Klimek, Andre T1 - Das Abplatzverhalten von Beton im Zusammenhang mit dem Maßstabseffekt N2 - Beton, als aktuell am meisten verwendeter Baustoff ist nicht brennbar und weist zudem eine sehr geringe Temperaturleitfähigkeit auf. Er eignet sich somit gut für den baulichen Brandschutz. Jedoch neigt Beton im Brandfall zu explosionsartigen Abplatzungen, die zu einer Reduzierung des tragfähigen Querschnitts und sogar zum Versagen des Bauteils führen können. Derzeit werden thermomechanische und thermohydraulische Schädigungsprozesse als die zwei maßgeblichen Ursachen für explosionsartige Abplatzungen angesehen. Diese Schädigungsprozesse sind unter anderem abhängig von der Prüfkörpergröße, dem Wasser-Zement-Wert, der Porosität, der Permeabilität und dem Bewehrungsgrad des Bauteils. Im Rahmen des Vortrags werden die Forschungsarbeiten zum Maßstabseffekt des Abplatzverhaltens von Betonen bei Brandbeanspruchung präsentiert. Zu diesem Zweck wurden Betonprüfkörper aus sechs verschiedenen Betonmischungen in jeweils drei Prüfkörpergrößen einseitig, ohne Behinderung der thermischen Ausdehnung und ohne externe Last im Tunnelbrandprüfstand der BAM untersucht. Dieser unikale Prüfstand ermöglicht die Brandprüfung unterschiedlicher Prüfkörpergrößen unter vergleichbaren Brandbedingungen sowie die simultane Prüfung mehrerer kleinformatiger Betonprüfkörper. Das präsentierte, laufende Promotionsvorhaben basiert auf einem von der DFG geförderten Forschungsvorhaben und darauf aufbauenden Folgeuntersuchungen. Die Ergebnisse des DFG-Vorhabens zeigen einen deutlichen Maßstabseffekt mit einer starken Verringerung der Abplatztiefen bei einer Reduzierung der Prüfkörpergröße. Des Weiteren ist das Abplatzverhalten stark von der Betonmischung abhängig. Vor dem Hintergrund der Ressourcenschonung und Kostenreduzierung verfolgen die auf dem DFG-Vorhaben aufbauenden Untersuchungen das Ziel, das Abplatzverhalten großformatiger Betonprüfkörper durch kleinformatige Betonprüfkörper mit angepassten Randbedingungen nachzustellen. Hierfür wurden zwei Betonmischungen des DFG-Vorhabens verwendet. Die Ergebnisse zeigen, dass durch eine Anpassung der Versuchsrandbedingungen dem Maßstabseffekt entgegengewirkt werden kann. T2 - 7. Symposium 'Heißbemessung - Structural Fire Engineering' CY - Online meeting DA - 14.09.2021 KW - Maßstabseffekt KW - Beton KW - Abplatzen KW - Brand PY - 2021 AN - OPUS4-53529 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz T1 - Prediction of building noise and vibration – 3D finite element and 1D wave propagation models N2 - Construction work or traffic excite nearby buildings, and the perceptible or audible vibration can be a nuisance for the inhabitants. The transfer of the vibration from the free field to the building has been calculated by the finite element method for many models in consultancy and research work. The analysis for all storeys of certain building points such as walls, columns and floors unveiled some rules, some typical modes, and some wavetype responses. A simplified building-soil model has been created, which includes well these effects of building-soil resonance, wall/column resonance, floor resonances, and the high-frequency reduction. The model consists of one wall for a wall-type apartment building or a column for each specific part (mid, side or corner) of a column-type office building. The building response in the high-frequency (acoustic) region is calculated as mean values over all storeys and over wider frequency bands, by wave-type asymptotes of an infinitely tall building, and by the soil to wall ratio of impedances. The secondary noise is predicted by Transfer values between the building vibration (center of floors, walls at a room corner) and the sound pressure. T2 - Euronoise 2021 CY - Online meeting DA - 25.10.2021 KW - Building vibration KW - Finite element models KW - Soil-wall-floor model KW - Apartment building KW - Office tower PY - 2021 SN - 978-989-53387-0-2 SP - 1792 EP - 1801 AN - OPUS4-53702 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz T1 - Prediction of building noise and vibration – 3D finite element and 1D wave propagation models N2 - Construction work or traffic excite nearby buildings, and the perceptible or audible vibration can be a nuisance for the inhabitants. The transfer of the vibration from the free field to the building has been calculated by the finite element method for many models in consultancy and research work. The analysis for all storeys of certain building points such as walls, columns and floors unveiled some rules, some typical modes, and some wavetype responses. A simplified building-soil model has been created, which includes well these effects of building-soil resonance, wall/column resonance, floor resonances, and the high-frequency reduction. The model consists of one wall for a wall-type apartment building or a column for each specific part (mid, side or corner) of a column-type office building. The building response in the high-frequency (acoustic) region is calculated as mean values over all storeys and over wider frequency bands, by wave-type asymptotes of an infinitely tall building, and by the soil to wall ratio of impedances. The secondary noise is predicted by Transfer values between the building vibration (center of floors, walls at a room corner) and the sound pressure. T2 - Euronoise 2021 CY - Online meeting DA - 25.10.2021 KW - Building vibration KW - Finite element models KW - Soil-wall floor model KW - Apartment building KW - Office tower PY - 2021 AN - OPUS4-53703 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz T1 - Die Amplitudenabnahme im Boden bei Punkt- und Zuglast N2 - Die Linienlastgesetzmäßigkeit gilt nicht für Zuganregung. Die Punktlastgesetzmäßigkeit wird bei kurzen Zügen in größeren Entfernungen erreicht. Bei langen Zügen reduziert sich die Abnahme um r-0,3 für die theoretische exponentielle Dämpfungsabnahme, um r-0,5 für die vereinfachte potentielle Dämpfungsabnahme. Die gemessenen Abnahmereduktionen liegen in diesem Bereich. T2 - Norm-Arbeitsausschuss Schwingungsminderung in der Umgebung von Verkehrswegen CY - Cologne/Germany und Online meeting DA - 28.10.2021 KW - Amplituden-Abstands-Gesetze KW - Geometrie KW - Dämpfung PY - 2021 AN - OPUS4-53704 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kauss, Norman A1 - Heyn, A. A1 - Michael, O. A1 - Schymura, M. A1 - Rosemann, P. T1 - Application limits and sensitisation behaviour of the manganese- and nitrogen-alloyed austenitic stainless steel P2000 (X13CrMnMoN18-14-3) N2 - Nickel‐free high‐nitrogen‐alloyed stainless steels like the P2000 (X13CrMnMoN18‐14‐3) were developed to enhance the strength and corrosion resistance of austenitic stainless steels like 304 and 316 while keeping the typical high ductility. The mechanical and corrosive properties of P2000 were investigated and compared with 304 and 316 to highlight the application opportunities of this new alloy. The microstructure of the solution‐annealed condition was characterised by electron backscatter diffraction and the mechanical properties were studied by uniaxial tensile tests, Charpy impact tests and hardness measurements. The passivation behaviour was analysed using the electrochemical potentiodynamic reactivation, whereas the pitting corrosion resistance was compared by pitting potentials and pitting temperatures. However, secondary thermal influences or suboptimal heat treatment can impair the corrosion resistance due to the precipitation of secondary phases and the resulting sensitisation. Thermodynamic calculations and artificial ageing treatment in the range of 500–900°C for up to 100 h were used to determine critical time–temperature parameters for sensitisation. The microstructure of the various aged states was evaluated by scanning electron microscopy and compared with the degrading corrosion resistance characterised by the KorroPad method. KW - Austenitic stainless steel KW - Electrochemical methods KW - High‐nitrogen steel KW - Mechanical properties KW - Corrosion resistance PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-527925 DO - https://doi.org/10.1002/maco.202112450 VL - 71 IS - 10 SP - 1656 EP - 1667 PB - Wiley-VCH GmbH AN - OPUS4-52792 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kinne, Marko A1 - Schneider, Ronald A1 - Thöns, Sebastian T1 - Reconstructing Stress Resultants in Wind Turbine Towers Based on Strain Measurements N2 - Support structures of offshore wind turbines are subject to cyclic stresses generated by different time-variant random loadings such as wind, waves, and currents in combinationwith the excitation by the rotor. In the design phase, the cyclic demand on wind turbine support structure is calculated and forecasted with semi or fully probabilistic engineering models. In some cases, additional cyclic stresses may be induced by construction deviations, unbalanced rotor masses and structural dynamic phenomena such as, for example, the Sommerfeld effect. Both, the significant uncertainties in the design and a validation of absence of unforeseen adverse dynamic phenomena necessitate the employment of measurement Systems on the support structures. The quality of the measurements of the cyclic demand on the support structures depends on (a) the precision of the measurement System consisting of sensors, amplifier and data normalization and (b) algorithms for analyzing and converting data to structural health information. This paper presents the probabilistic modelling and analysis of uncertainties in strain measurements performed for the purposes of reconstructing stress resultants in wind turbine towers. It is shown how the uncertainties in the strain measurements affect the uncertainty in the individual components of the reconstructed forces and moments. The analysis identifies the components of the vector of stress resultants that can be reconstructed with sufficient precision. T2 - International Conference on Uncertainty in Mechanical Engineering - ICUME CY - Online meeting DA - 07.06.2021 KW - Reconstruction of stress resultants KW - Strain measurements KW - Bayesian updating of measurement uncertainties PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-527987 DO - https://doi.org/10.1007/978-3-030-77256-7_18 SP - 224 EP - 235 PB - Springer AN - OPUS4-52798 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kinne, Marko T1 - Influence of the structural integrity management on the levelized cost of energy of offshore wind: a parametric sensitivity analysis N2 - Due to the energy transition in Germany and the European Union, the relevance of renewable energy is steadily increasing. Besides hydropower and solar energy, offshore and onshore wind energy already forms a major part of renewables energies and will also be further expanded in the future (COMMISSION, 2020). In addition to the investments in the expansion of renewable energy, further research and development should focus on reducing the levelized cost of energy (LCoE) of wind energy to improve its market position. The LCoE is the average net cost of electricity generated by a power plant that converts a certain type of energy into electrical power. The LCoE is estimated as the ratio of the discounted lifetime costs (i.e. capital expenditures (CAPEX) plus operational expenditures (OPEX)) to the discounted sum of the annual energy production (AEP) over its lifetime. For an offshore wind farm, the CAPEX contain the investment costs for the structures and remaining parts of the wind farm. The OPEX include the cost related to the structural integrity management (SIM) and the operation and maintenance of the remaining parts. The AEP is a function of the number of turbines, the nominal (turbine) capacity, the nominal capacity availability factor, the turbine availability, and the feed in tariff. Several options are available to reduce the LCoE of a wind farm. For example, the energy production can be increased by increasing the turbine availability. Another option is to optimize the SIM and thus reduce the OPEX. To study the influence of SIM on the LCoE of a wind farm, we perform a variance-based sensitivity analysis of the LCoE (Saltelli et al., 2008). In this analysis, the importance of a given parameter influencing the LCoE is measured in term of its first-order sensitivity index, which quantifies the contribution the parameter to the variance of the LCoE. The CAPEX and OPEX are decomposed into costs related to the structures and costs associated to the remaining parts of the wind farm. The mean value of the CAPEX and OPEX related to the structures and the remaining parts are determined based on a literature study. The OPEX related to the structures are assumed to be in accordance with the requirements and regulations of German Hydrographic Authority (Hydrographie, 2015). They amount to 1.6% of the total OPEX for an average scenario (Martinez-Luengo and Shafiee, 2019). The determined sensitivity indices for the parameters influencing the LCoE are shown (Figure 1). The nominal capacity, the nominal capacity availability factor, the turbine availability factor, and the feed in tariff have the highest (first-order) sensitivity indices. The CAPEX and OPEX for the wind turbine support structures have small sensitivity indices. It can be concluded that an optimization of the SIM may have negligible influence on the LCoE. However, an extension of the service life by means of structural health information (Thöns et al., 2017) may have an effect due to its reasonable influence on the LCoE . T2 - WESC CY - Online meeting DA - 25.05.2021 KW - Sensitivity analysis KW - Structural integrity management KW - Levelized cost of energy PY - 2021 AN - OPUS4-52868 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bäßler, Ralph A1 - Stoljarova, A. A1 - Regenspurg, S. T1 - Influence of Precipitating Brine Components on Materials Selection for Geothermal Applications N2 - Since geothermal wells are a feasible energy source to replace fossil fuel supply, many technologies have been developed to take advantage of geothermal energy. Nevertheless, service conditions in geothermal facilities are in many cases extreme in terms of corrosion due to the chemical composition of hydrothermal fluids and temperatures. Therefore, materials selection based on preliminary material qualification is essential to guarantee a secure and reliable operation of the facilities. During operation of a geothermal research facility in Groß Schönebeck copper and lead effects have been found downhole. Occurring mechanisms and measures to prevent precipitation or scaling needed to be investigated as well as potential influences of such precipitates on corrosion resistance of metallic materials used for equipment. This contribution deals with the evaluation of the corrosion behavior of carbon steel and corrosion resistant alloys in copper and/or lead containing artificial geothermal water, simulating the conditions in the Northern German Basin. The behavior of these materials in an artificial geothermal water obtained by electrochemical measurements and exposure tests are presented. While carbon steel exhibits precipitation and deposition, higher alloyed material shows different response to such species and a higher resistance in saline geothermal water. Basing on these results the suitability of the investigated corrosion resistant alloy is given for use in such conditions, whereas carbon steel creates difficulties due to its susceptibility to Cu- and Pb-precipitation. T2 - World Geothermal Congress CY - Online meeting DA - 30.03.2021 KW - Copper KW - Lead KW - Corrosion KW - Steel KW - Geothermal energy PY - 2021 SP - 1 EP - 11 AN - OPUS4-52828 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Aristia, Gabriela A1 - Le, Quynh Hoa A1 - Bäßler, Ralph T1 - Study of Polyaniline/Silicon Dioxide based Coating on Carbon Steel in Artificial Geothermal Brine N2 - Geothermal brines are corrosive in nature because of their salt contents and high temperatures. Therefore, they pose a major challenge to geothermal power-plants, which are mostly built of low alloyed steels, e.g., carbon steel. Carbon steel is susceptible to uniform and localized corrosion when exposed to geothermal brines having acidic-saline properties. To overcome this limitation, geothermal power plants should be built by either high alloyed materials or by integrating protection systems on carbon steel, such as coatings and inhibitors. We studied a coating system containing polyaniline/silicon dioxide basing on locally available resources that provides protection against corrosion of carbon steel and enhance the thermal resistance in geothermal environments. Here, exposure and electrochemical tests of coated carbon steels were performed in an artificial geothermal brine. The solution had a pH of 4, with the composition of 1,500 mg/L of chlorides, which is based on the chemical analysis of geothermal brine found in Sibayak, Indonesia. All exposure tests were conducted using autoclaves at 150 °C with a total pressure of 1 MPa, which was performed for up to six months to evaluate the durability of the coating system. Post-experimental analyses were performed by assessing the surface of specimens using optical and electron microscopes. On the other hand, electrochemical tests were performed for seven days at 25 °C and 150 °C to investigate the kinetics of electrochemical reactions by measuring open circuit potential and electrochemical impedance spectra. Experimental results showed the corrosion resistance of PANI/SiO2 composite coatings, where polyaniline and SiO2 play their roles as stabilizers. T2 - World Geothermal Congress CY - Online meeting DA - 30.03.2021 KW - Coatings KW - Corrosion KW - Polyaniline KW - Sibayak KW - SiO2 PY - 2021 SP - 1 EP - 7 AN - OPUS4-52830 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Babutzka, Martin T1 - Investigation of the salinization in marine and offshore environment - test methods and challenges N2 - Salinization and contamination of metal surfaces by chloride-containing aerosols is of great importance with regard to corrosion phenomena in the maritime sector and in offshore applications. The evaluation of the scientific literature and regulatory guidelines has shown that there are still many open questions regarding the contamination of metal surfaces by chlorides. This contribution will discuss how salinization of metal surfaces is evaluated and monitored according to current standards and guidelines. T2 - 3rd Task Group Meeting TC124 WG4-TC 250 SC5 Task Group Corrosion CY - Online Meeting DA - 19.05.2021 KW - Maritime atmosphere KW - Salinization KW - Corrosion PY - 2021 AN - OPUS4-52677 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Häßler, Dustin A1 - Hothan, Sascha A1 - Häßler, M. A1 - Krüger, Simone T1 - Thermische Schutzwirkung von reaktiven Brandschutzsystemen auf kleinformatigen Stahlbauteilen mit gekrümmter Oberfläche T1 - Thermal protection effect of reactive fire protection systems on small-scale steel components with curved surfaces N2 - Um Stahlbauteile im Brandfall vor einer zu schnellen Erwärmung zu schützen, wird häufig auf reaktive Brandschutzsysteme (RBS) zurückgegriffen. Die Produkte eigenen sich besonders aufgrund der profilfolgenden Applikationsmöglichkeit und der vergleichsweise geringen Beschichtungsdicken. Bei einer Brandbeanspruchung schäumt das RBS auf und bildet eine thermische Schutzschicht um das Stahlprofil aus. Dadurch wird die Erwärmung des Stahls verlangsamt und der temperaturbedingte Festigkeitsverlust verzögert, wodurch sich die Feuerwiderstandsdauer des Stahlbauteils verbessert. Aus Brandversuchen ist bekannt, dass die Leistungsfähigkeit von RBS auf Stahlprofilen mit gekrümmter Oberfläche meist schlechter ausfällt als bei vergleichbaren Bauteilen mit ebener Oberfläche. Zum Einfluss der Oberflächenkrümmung auf die thermische Schutzwirkung von RBS werden in dem folgenden Beitrag sowohl theoretische Hintergründe als auch die Ergebnisse aus Brandversuchen an kleinformatigen Probekörpern vorgestellt. Die systematischen Untersuchungen zeigen, dass mit zunehmender Oberflächenkrümmung die Leistungsfähigkeit des RBS tendenziell abnimmt. Bei der Beurteilung der thermischen Schutzwirkung eines RBS sollte die Oberflächenkrümmung eines Bauteils berücksichtigt werden. Die alleinige Fokussierung auf den Profilfaktor eines Stahlprofils ist im Allgemeinen nicht ausreichend. Die Untersuchungen bilden die Grundlage für die Entwicklung von Screening-Tests zur Beurteilung der Eignung von RBS für gekrümmte Oberflächen, wodurch eine Vorauswahl von Produkten für diesen Einsatzzweck ermöglicht wird. N2 - Intumescent fire protection coatings, also referred to as reactive fire protection systems, are often used to protect steel components from heating up too quickly in the event of a fire. The products are particularly suitable due to profile-following application as well as the comparatively low coating thickness. If exposed to fire, the intumescent coating foams up and forms a thermal protective layer around the steel profile. This slows down the heating of the steel and delays the temperature-related loss of strength, which improves the fire resistance of the steel component. From fire tests it is known that the performance of intumescent coatings on steel profiles with a curved surface is usually worse than on comparable components with a flat surface. The following article presents the theoretical background as well as the results from fire tests on small-scale specimens to show the influence of surface curvature on the thermal protective effect of intumescent fire protection coatings. The systematic investigations show that with increasing surface curvature, the performance of the intumescent coating tends to decrease. When assessing the thermal protective effect of an intumescent coating, the surface curvature of a steel component should be considered. Focusing solely on the profile factor of a steel profile is generally not sufficient. The research forms the basis for the development of screening tests to assess the suitability of intumescent coatings for curved surfaces, enabling a pre-selection of products for this application. KW - Stahl KW - Brandschutz KW - Reaktive Brandschutzsysteme KW - Brandversuche KW - Oberflächenkrümmung KW - Intumeszierende Beschichtung PY - 2021 DO - https://doi.org/10.1002/bate.202100011 SN - 0932-8351 SN - 1437-0999 VL - 98 IS - 5 SP - 333 EP - 344 PB - Ernst & Sohn Verlag CY - Berlin AN - OPUS4-52654 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Fürst, Richard A1 - Fürst, E. A1 - Vlach, T. A1 - Repka, J. A1 - Pokorny, M. A1 - Mozer, V. T1 - Use of Cement Suspension as an Alternative Matrix Material for Textile-Reinforced Concrete N2 - Textile-reinforced concrete (TRC) is a material consisting of high-performance concrete (HPC) and tensile reinforcement comprised of carbon roving with epoxy resin matrix. However, the problem of low epoxy resin resistance at higher temperatures persists. In this work, an alternative to the epoxy resin matrix, a non-combustible cement suspension (cement milk) which has proven stability at elevated temperatures, was evaluated. In the first part of the work, microscopic research was carried out to determine the distribution of particle sizes in the cement suspension. Subsequently, five series of plate samples differing in the type of cement and the method of textile reinforcement saturation were designed and prepared. Mechanical experiments (four-point bending tests) were carried out to verify the properties of each sample type. It was found that the highest efficiency of carbon roving saturation was achieved by using finer ground cement (CEM 52.5) and the pressure saturation method. Moreover, this solution also exhibited the best results in the four-point bending test. Finally, the use of CEM 52.5 in the cement matrix appears to be a feasible variant for TRC constructions that could overcome problems with its low temperature resistance. KW - Textile-reinforced concrete KW - High-performance concrete KW - Carbon fibers KW - Cement matrix PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-527100 DO - https://doi.org/10.3390/ma14092127 SN - 1996-1944 VL - 14 IS - 9 SP - 2127 PB - MDPI CY - Basel AN - OPUS4-52710 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Fürst, Richard A1 - Vlach, T. A1 - Pokorny, M. A1 - Mozer, V. T1 - Study of Behavior of Textile-Reinforced Concrete with Epoxy Resin Matrix in Fire N2 - Textile-reinforced concrete is currently most frequently used for non-load–bearing structures, but there is a vision for also using it in load–bearing construction elements. In recent years, this construction material has been subjected to detailed examination. Different combinations of materials for potential use in textile-reinforced concrete have been described. These differ in the type of concrete mix and the composition of the textile reinforcement. The aim of this work is to test the application of a specific textile-reinforced concrete, consisting of high-performance concrete, textile reinforcement from carbon fibers and its epoxy resin matrix, at an elevated temperature. The combination of these materials makes it possible to produce subtle load–bearing structures with excellent mechanical properties. The critical issue is the behavior of these structures when exposed to fire. A series of medium-scale fire condition experiments were carried out with a temperature load based on the ISO 834 curve, followed up by mechanical tests. The aim of these experiments was to describe critical areas of textile-reinforced concrete in fire and to propose possible solutions. In an indicative fire experiment, experimental samples displayed massive spall of concrete layers, and interaction between materials was lost due to the low temperature resistance of the epoxy resin. Concurrently, the optimal quantity of polypropylene fibers was experimentally determined. This paper presents an experimental demonstration of the problematic aspects of textile-reinforced concrete and subsequent recommendations for future work with practical application in the design of load–bearing structures. KW - Textile-reinforced concrete KW - High-performance concrete KW - Carbon fibers KW - Epoxy resin KW - Load–bearing structures KW - Fire resistance PY - 2021 DO - https://doi.org/10.1007/s10694-021-01116-y SN - 1572-8099 SN - 0015-2684 SP - 1 EP - 22 PB - Springer AN - OPUS4-52712 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schneider, Ronald T1 - Towards predictive maintenance of bridges N2 - Key features of predictive maintenance of structural systems are discussed and demonstrated in two examples. Challenges and needs for further research are discussed. T2 - Workshop Bridge Maintenance CY - Online Meeting DA - 09.04.2021 KW - Predictive maintenance KW - Deterioration KW - Structural systems PY - 2021 AN - OPUS4-52768 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schneider, Ronald A1 - Straub, D. ED - Matos, J.C. ED - Lourenço, P.B. ED - Oliveira, D.V. ED - Branco, J. ED - Proske, D. ED - Silva, R.A. ED - Sousa, H.S. T1 - Cumulative Failure Probability of Deteriorating Structures: Can It Drop? N2 - The reliability of deteriorating structures at time t is quantified by the probability that failure occurs within the period leading up to time t. This probability is often referred to as cumulative failure probability and is equal to the cumulative distribution function of the time to failure. In structural reliability, an estimate of the cumulative failure probability is obtained based on probabilistic Engineering models of the deterioration processes and structural performance. Information on the condition and the loading contained in inspection and monitoring data can be included in the probability estimate through Bayesian updating. Conditioning the probability of failure on the inspection or monitoring outcomes available at time t (e.g. detections or no detection of damages) can lead to a reduction in that probability. Such a drop in the cumulative failure probability might seem counterintuitive since the cumulative failure probability is a non-decreasing function of time. In this paper, we illustrate—with the help of a numerical example—that such a drop is possible because the cumulative probability before and after the updating is not based on the same information, hence not on the same probabilistic model. T2 - 18th International Probabilistic Workshop (IPW 2020) CY - Online meeting DA - 12.05.2021 KW - Deterioration KW - Structural systems KW - Time-variant reliability KW - Bayesian updating KW - Inspection KW - Monitoring PY - 2021 DO - https://doi.org/10.1007/978-3-030-73616-3_18 VL - 153 SP - 253 EP - 264 PB - Springer CY - Cham, Switzerland AN - OPUS4-52769 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schneider, Ronald T1 - Cumulative failure probability of deteriorating structures: Can it drop? N2 - The reliability of deteriorating structures at time t is quantified by the probability that failure occurs within the period leading up to time t. This probability is often referred to as cumulative failure probability and is equal to the cumulative distribution function of the time to failure. In structural reliability, an estimate of the cumulative failure probability is obtained based on probabilistic engineering models of the deterioration processes and structural performance. Information on the condition and the loading contained in inspection and monitoring data can be included in the probability estimate through Bayesian updating. Conditioning the probability of failure on the inspection or monitoring outcomes available at time t (e.g. detections or no detection of damages) can lead to a reduction in that probability. Such a drop in the cumulative failure probability might seem counterintuitive since the cumulative failure probability is a non-decreasing function of time. In this paper, we illustrate—with the help of a numerical example—that such a drop is possible because the cumulative probability before and after the updating is not based on the same information, hence not on the same probabilistic model. T2 - 18th Internatinoal Probabilistic Workshop (IPW 2020) CY - Online Meeting DA - 12.05.2021 KW - Deterioration KW - Structural systems KW - Time-variant reliability KW - Bayesian updating KW - Inspection KW - Monitoring PY - 2021 AN - OPUS4-52770 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Farhan, Muhammad A1 - Schneider, Ronald A1 - Thöns, Sebastian T1 - Predictive information and maintenance optimization based on decision theory: a case study considering a welded joint in an offshore wind turbine support structure N2 - Predictive information and maintenance optimization for deteriorating structures is concerned with scheduling (a) the collection of information by inspection and monitoring and (b) maintenance actions such as repair, replacement, and retrofitting based on updated predictions of the future condition of the structural system. In this article, we consider the problem of jointly identifying—at the beginning of the service life—the optimal inspection time and repair strategy for a generic welded joint in a generic offshore wind turbine structure subject to fatigue. The optimization is performed based on different types of decision analyses including value of information analyses to quantify the expected service life cost encompassing inspection, repair, and fatigue damage for all relevant combinations of inspection time, repair method, and repair time. Based on the analysis of the expected service life cost, the optimal inspection time, repair method, and repair time are identified. Possible repair methods for a welded joint in an offshore environment include welding and grinding, for which detailed models are formulated and utilized to update the joint’s fatigue performance. The decision analyses reveal that an inspection should be scheduled approximately at mid-service life of the welded joint. A repair should be performed in the same year after an indication and measurement of a fatigue crack given an optimal inspection scheduling. This article concludes with a discussion on the results obtained from the decision and value of information analyses. KW - Integrity management KW - Value of information KW - Decision theory KW - Structural reliability KW - Fracture mechanics KW - Fatigue KW - Predictive maintenance KW - Wind turbine support structure PY - 2021 DO - https://doi.org/10.1177/1475921720981833 SN - 1475-9217 SN - 1741-3168 PB - Sage Publications CY - London AN - OPUS4-52771 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CHAP A1 - Schartel, Bernhard ED - Troitzsch, J. ED - Antonatus, E. T1 - The Burning of Plastics N2 - The burning of a polymer is a physico–chemical process strongly influenced by the coupling of a chemical reaction – oxidation of fuel – in the gas phase with a chemical decomposition reaction – pyrolysis – in the condensed phase via heat and mass transfer. The heat and mass flux control the intensity of fire and the ablation of fuel. Indeed, the temperature profile as a function of time may be one of the most important responses of a specimen to understand its burning behavior. Further, several physical phenomena, such as the heat absorption of the materials, thermal conductivity, and also melt flow and dripping, play a major role in determining ignition, flammability, and fire behavior. The burning of a polymer is very complex. The various phenomena interact with each other, e. g., pyrolysis also influences the viscosity of the melt, and, thus, whether dripping or charring results in a protective layer, increasing the shielding effect of the residual protective layer. Only a detailed and comprehensive description opens the door to a well-founded understanding of the burning behavior of polymeric materials. KW - Fire behaviour KW - Plastics KW - Pyrolysis KW - Decomposition KW - Ignition KW - Smoldering KW - Flame spread KW - Steady burning KW - Fire load KW - Fire resistance PY - 2021 SN - 978-1-56990-762-7 SP - 23 EP - 52 PB - Hanser CY - Munich ET - 4th Edition AN - OPUS4-52684 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bäßler, Ralph T1 - Determination of Corrosivity: Approach according to UN Regulations N2 - “Corrosive to Metals” (H290) describes the general potential danger of a substance to metallic materials. Uniform and localized attack is considered. It has nothing to do with containment material. Corrosion resistance of materials is determined similarly, but with much lower threshold values. Manual shall provide a simple test to easily determine the aggressivity potential to cause corrosion on metallic materials. Even a simple test requires experienced personnel. There seems to be a need of awareness and understanding training for both officials and applicants. T2 - ECHA GHS Training CY - Online meeting DA - 16.03.2021 KW - Corrosivity KW - Dangerous good KW - Corrosion PY - 2021 AN - OPUS4-52295 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Long, Lijia A1 - Alcover, I. F. A1 - Thöns, Sebastian T1 - Utility analysis for SHM durations and service life extension of welds on steel bridge deck N2 - Optimization of the duration of Structural Health Monitoring (SHM) campaigns is rarely performed. This article provides a utility-based solution to posteriorly determine: i) optimal monitoring Durations and ii) the extension of the service life of the welds on a steel bridge deck. The approach is Illustrated with a case study focusing on remaining fatigue life estimation of the welds on the orthotropic steel deck of the Great Belt Bridge, in Denmark. The identification of the optimal monitoring duration and the decision about extending the service life of the welds are modelled by maximizing the expected benefits and minimizing the structural risks. The results are a parametric analysis, mainly on the effect of the target probability, benefit, cost of failure, cost of rehabilitation, cost of monitoring and Discount rate on the posterior utilities of monitoring strategies and the choice of service life considering the risk variability and the costs and benefits models. The results show that the decision on short-term monitoring, i.e., 1 week every six months, is overall the most valued SHM strategy. In addition, it is found that the target probability is the most sensitive parameter affecting the optimal SHM Durations and service life extension of the welds. KW - Fatigue KW - Monitoring strategy KW - Orthotropic steel deck KW - Structural health monitoring KW - Utility and decision theory PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-521719 DO - https://doi.org/10.1080/15732479.2020.1866026 SN - 1573-2479 VL - 18 IS - 4 SP - 492 EP - 504 PB - Taylor Francis Online AN - OPUS4-52171 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Auersch, Lutz A1 - Said, Samir T1 - Dynamic track-soil interaction – calculations and measurements about slab and ballast tracks N2 - The dynamic behaviour of slab and ballast tracks has been investigated by measurements and calculations. Hammer impacts and train passages have been analysed. Measurements have been performed by geophones (velocity transducers) which have been time-integrated to displacements. The calculations are done in frequency-wavenumber domain for multi-beam-on-continuous soil models. The characteristics of the different tracks and track elements have been established in theory and experiment. The frequency-dependent compliances (displacement transfer functions) show clear rail-on-rail-pad resonances or highly damped track-soil resonances. Compared to the rail and sleeper, the track plate has much lower amplitudes. The slab track has usually the highest rail amplitudes due to soft rail pads. The train passage yields track displacements which are a superposition of the axle loads from the two neighbouring axles of a bogie and from the two bogies of two neighbouring carriages. This global behaviour is characteristic for the track plate of the slab track whereas the rails of the slab and the ballast track behave more local with only one bogie of influence. The measurements agree very well with the theory of the continuous soil in case of the six measured slab tracks and acceptably well for the six measured ballast tracks. The measurements allow to find appropriate model parameters and to check the models, for example the Winkler model of the soil has been found less appropriate as it reacts more locally. KW - Slab track KW - Ballast track KW - Train passage KW - Hammer impact KW - Track-soil interaction PY - 2021 DO - https://doi.org/10.1631/jzus.A1900651 SN - 1673-565X VL - 22 IS - 1 SP - 21 EP - 36 PB - Zhejiang University Press CY - Hangzhou AN - OPUS4-52107 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - THES A1 - Eberwein, Robert T1 - Untersuchung der Gefährdung von Personen und Bauwerken in Folge des Versagens von LNG-Kraftstoffspeichern für Fahrzeuge in Tunneln N2 - Liquefied Natural Gas (LNG) aus regenerativen Quellen, stellt einen potenziellen Kraftstoff für den Schwer- und Fernverkehr des Straßenverkehrs dar. Gegenüber seinen positiven Eigenschaften zu dem in diesem Verkehrssektor häufig verwendeten Kraftstoff Diesel birgt der Kraftstoff aber auch Gefahren für Personen und Bauwerke durch seine sehr niedrige Temperatur bei der Speicherung von ca. -160 °C und seine Explosionsfähigkeit in der Gas-Phase. In der Arbeit wurde sich mit der Gefährdung von Personen und Bauwerken hinsichtlich der von LNG ausgehenden Gefahren in Tunneln auseinandergesetzt. Tunnel stellen besonders schützenswerte Bauwerke dar, da aus vorhergehenden Störfällen in Tunneln bekannt ist, dass diese mit hohen Personen-, Bauwerks-, und Volkswirtschaftlichen-Schäden einhergehen können. Untersuchungsschwerpunkt bei der Bewertung von Gefährdungen durch LNG stellte eine Ereigniskaskade bestehend aus Freisetzung, Verdampfung, Stoffausbreitung und Zündung des sich gebildeten explosionsfähigen LNG-Gas/Luft-Gemisches dar. Mit dem Ziel eine solche Ereigniskaskade realitätsnah vorhersagen und zukünftig hierzu Risikoanalysen durchführen zu können wurden innerhalb der Arbeit Parameterstudien sowie Kalibrierungen und Validierungen gegenüber experimentellen Untersuchungen durchgeführt. Mit den Modellen wurden in der Arbeit exemplarische Fallbeispiele zu Störfällen untersucht. Ergebnisse dieser waren, dass Gefährdungen insbesondere von flüssigem LNG nach dessen Freisetzung und der Verbrennung von LNG-Gas/Luft-Gemischen ausgingen. N2 - Liquefied Natural Gas (LNG) from regenerative sources is a potential fuel for heavy and long-distance road traffic. In contrast to its positive properties compared to diesel, which is often used in this transport sector, the fuel also contains hazards from its very low storage temperature of approx. -160 °C and its explosiveness in the gas phase for personal and structural safety. The dissertation dealt with the dangers to persons and infrastructures according to the hazards by LNG in tunnels. Tunnels are especiallyworth protecting structures since it is known from previous incidents in tunnels that they can go hand in hand with high damage to the people, the structure, and the economy. The main focus of the investigation into the assessment of hazards from LNG was an event cascade consisting of release, evaporation, dispersion, and ignition of the explosive LNG-vapor/air-mixture formed. To realistically predict such an event cascade and being able to carry out risk analyzes for this purpose in the future, parameter studies such as calibrations and validations were carried out concerning experimental investigations. Exemplary case studies on incidents were examined in the thesis with the validated models. The results of this were that there were especially hazards in particular from liquid LNG after its release and the combustion of LNG-vapor/air-mixtures. KW - Verflüssigtes Erdgas KW - Erneuerbare Energien KW - Numerische Strömungsmechanik KW - Sicherheitstechnik KW - Liquefied Natural Gas KW - LNG KW - Renewable fuels KW - CFD KW - Safety engineering PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-521145 DO - https://doi.org/10.14279/depositonce-11346 SP - 1 EP - 240 PB - TU Berlin CY - Berlin AN - OPUS4-52114 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Tiebe, Carlo A1 - Zunkel, Astrid A1 - Klein, Ulrich A1 - Schlischka, Jörg A1 - Klinger, Christian T1 - Materialuntersuchungen zur Schadensanalyse an einem explodierten Umlaufkühler N2 - Ein Durchlaufkühler ist im Betrieb explodiert. Die zerborstenen Gehäuseteile aus Kunststoff führten zu einem Austreten der Kühlflüssigkeit am Betriebsort sowie zu einem Personenschaden mit Knalltrauma. Bei Funktionsprüfungen am beschädigten Gerät traten unerwartet, aber reproduzierbar Knalleffekte auf der Kupfer-Kühlschlange auf. Ein möglicher Mechanismus konnte im Labor durch Synthese von Kupferazid auf Kupferproben und Auslösung vergleichbarer Knalleffekte nachgestellt werden. Damit ist die Plausibilität des beschriebenen Schadensereignisses mit diesem oder einem ähnlich reagierenden Stoff belegt. Ein eindeutiger Nachweis darüber, dass beim aufgetretenen Schadensfall dieselbe chemische Reaktion stattgefunden hat ist nicht möglich, da die Belag-Überreste aus dem explodierten Kühlgerät für eine Analyse nicht mehr in ausreichender Menge verfügbar waren. T2 - Erfahrungsaustausch für Sachverständige in der Anlagenüberwachung der Industrie (ESA 2021) CY - Online meeting DA - 20.04.2021 KW - Umlaufkühler KW - Schadensanalyse KW - Materialuntersuchungen KW - Gutachten KW - Kupferazid PY - 2021 AN - OPUS4-52484 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Aristia, Gabriela A1 - Le, Quynh Hoa A1 - Nofz, Marianne A1 - Sojref, Regine A1 - Bäßler, Ralph T1 - Study of Al2O3 Sol-Gel Coatings on X20Cr13 in Artificial North German Basin Geothermal Water at 150 °C N2 - Al2O3 has been widely used as a coating in industrial applications due to its excellent chemical and thermal resistance. Considering high temperatures and aggressive mediums exist in geothermal systems, Al2O3 can be a potential coating candidate to protect steels in geothermal applications. In this study, γ-Al2O3 was used as a coating on martensitic steels by applying AlOOH sol followed by a heat treatment at 600 °C. To evaluate the coating application process, one-, two-, and three-layer coatings were tested in the artificial North German Basin (NGB), containing 166 g/L Cl−, at 150 °C and 1 MPa for 168 h. To reveal the stability of the Al2O3 coating in NGB solution, three-layer coatings were used in exposure tests for 24, 168, 672, and 1296 h, followed by surface and cross-section characterization. SEM images show that the Al2O3 coating was stable up to 1296 h of exposure, where the outer layer mostly transformed into boehmite AlOOH with needle-like crystals dominating the surface. Closer analysis of cross-sections showed that the interface between each layer was affected in long-term exposure tests, which caused local delamination after 168 h of exposure. In separate experiments, electrochemical impedance spectroscopy (EIS) was performed at 150 °C to evaluate the changes of coatings within the first 24 h. Results showed that the most significant decrease in the impedance is within 6 h, which can be associated with the electrolyte penetration through the coating, followed by the formation of AlOOH. Here, results of both short-term EIS measurements (up to 24 h) and long-term exposure tests (up to 1296 h) are discussed. KW - Al2O3 KW - Geothermal KW - Martensitic steels KW - Behmite KW - Corrosion PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-525551 DO - https://doi.org/10.3390/coatings11050526 SN - 2079-6412 VL - 11 IS - 5 SP - 526 PB - MDPI CY - Basel AN - OPUS4-52555 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schartel, Bernhard T1 - Flammschutzmittel in PUR: Eine alte, aktuelle und zukünftige Herausforderung N2 - Überblick über die Herausforderungen, Anforderungen und Lösungswege für den Flammschutz von Polyurethanwerkstoffen (thermoplastisches und elastomeres Polyurethan (TPU, PUR), PUR Hard- und Weichschäume, PIR, PUR Coatings). Die Werkstoffcharakteristika wie Pyrolyse, effektive Verbrennungswärme, Rückstandsausbeute, Verarbeitungsparameter und kg-Preis definieren die Anforderungen an Flammschutzlösungen. Der Flammschutz ist spezifisch für das Material ausgelegt, aber auch für die verschiedenen Anwendungen (Automobilbau, Schienenfahrzeuge, Bauwesen, Elektrotechnik, usw.), d.h. um spezielle Brandtests zu bestehen. Die Pyrolyse und das Brandverhalten von PUR und PUR-Schäumen sowie der flammgeschützten Varianten wird diskutiert. Die gängigen Flammschutzmittel(-kombinationen) werden zusammengefasst und mit Beispielen belegt. T2 - PUR Forum, Flammenschutz in der Polyurethanverarbeitung CY - Online meeting DA - 05.05.2021 KW - Polyurethan KW - Pyrolyse KW - Flammschutz KW - Expandierbarer Graphit KW - Schaum KW - TPU PY - 2021 AN - OPUS4-52590 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Auersch, Lutz ED - Degrande, G. ED - al., et T1 - Predicted and measured amplitude-speed relations of railway ground vibrations at four German sites with different test trains N2 - The present contribution evaluates four measuring series made by the Federal Institute of Material Research and Testing for the relations between train speed and ground vibration amplitudes. This experimental evaluation is supported by the simulation of the train passages at the different sites by using appropriate excitation mechanisms and forces as well as layered soil models which have been derived from impact measurements at each site. KW - Train speed KW - Ground vibration KW - Excitation forces KW - Layered soils PY - 2021 SN - 978-3-030-70288-5 DO - https://doi.org/10.1007/978-3-030-70289-2_43 SN - 1612-2909 VL - 150 SP - 411 EP - 419 PB - Springer Nature Switzerland AG CY - Cham AN - OPUS4-52611 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Müller, R. A1 - Brechbühl, Y. A1 - Lutzenberger, S. A1 - Said, Samir A1 - Auersch, Lutz A1 - Guigou-Carter, C. A1 - Villot, M. A1 - Müller, R. ED - Degrande, G. ED - al., et T1 - Vibration Excitation at Turnouts, Mechanism, Measurements and Mitigation Measures N2 - There is a strong need for cost-effective mitigation measures for turnouts. SBB has initiated a series of examinations using different methodologies to gain a deeper understanding of the excitation mechanisms at low frequencies, in addition to that obtained in the RIVAS project. To date it is not yet clear what constitutes a complete measurement data set that would enable understanding most of the vibration excitation mechanisms in turnouts. Increasing vibration at turnouts in comparison to normal track is observed for all measured frequencies. The different methodologies are presented in the paper. Under-sleeper pads (USP) are a cost-effective method to reduce vibration at frequencies above 63 Hz (1/3 octave), but there is probably no improvement for frequencies below 63 Hz. A first test of new frog geometry did not show relevant improvements in Vibration emission in comparison to a reference frog geometry. Axle box acceleration measurements are an interesting method to identify defects in a turnout. A specialized measurement system of rail roughness could identify certain geometry Problem areas for some frogs. Noise increases also are observed at turnouts for frequencies ranging between 80 to 1000 Hz. The use of railway source models to calculate contact forces for ballasted track and turnouts seems promising, in particular for understanding the influence of ground. KW - Turnout KW - Switch KW - Vibration excitation KW - Vibration measurements PY - 2021 SN - 978-3-030-70288-5 DO - https://doi.org/10.1007/978-3-030-70289-2_42 SN - 1612-2909 VL - 150 SP - 403 EP - 410 PB - Springer Nature Switzerland AG CY - Cham AN - OPUS4-52612 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Battig, Alexander A1 - Müller, Patrick A1 - Bertin, Annabelle A1 - Schartel, Bernhard T1 - Hyperbranched Rigid Aromatic Phosphorus-Containing Flame Retardants for Epoxy Resins N2 - A rigid aromatic phosphorus-containing hyperbranched flame retardant structure is synthesized from 10-(2,5 dihydroxyphenyl)-10H-9-oxa- 10-phosphaphenanthrene-10-oxide (DOPO-HQ), tris(4-hydroxyphenyl)phosphine oxide (THPPO), and 1,4-terephthaloyl chloride (TPC). The resulting poly-(DOPO-HQ/THPPO-terephthalate) (PDTT) is implemented as a flame retardant into an epoxy resin (EP) at a 10 wt% loading. The effects on EP are compared with those of the monomer DOPO-HQ and triphenylphosphine oxide (OPPh3) as low molar mass flame retardants. The glass transition temperature, thermal decomposition, flammability (reaction to small flame), and burning behavior of the thermosets are investigated using differential scanning calorimetry, thermogravimetric analysis, pyrolysis combustion flow calorimetry, UL 94-burning chamber testing, and cone calorimeter measurements. Although P-contents are low at only 0.6 wt%, the study aims not at attaining V-0, but at presenting a proof of principle: Epoxy resinswith PDTT show promising fire performance, exhibiting a 25% reduction in total heat evolved (THE), a 30% reduction in peak heat release rate (PHRR) due to flame inhibition (21% reduction in effective heat of combustion (EHC)), and an increase in Tg at the same time. This study indicates that rigid aromatic hyperbranched polymeric structures offer a promising route toward multifunctional flame retardancy. KW - Hyperbranched KW - Aromatic KW - Phosphorus KW - Phosphine oxide KW - DOPO KW - Flame retardant KW - Xpoxy resin KW - Rigid PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-525910 DO - https://doi.org/10.1002/mame.202000731 SN - 1439-2054 VL - 306 IS - 4 SP - 731 PB - Wiley AN - OPUS4-52591 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Eberwein, Robert T1 - Untersuchung der Gefährdung von Personen und Bauwerken in Folge des Versagens von LNG-Kraftstoffspeichern für Fahrzeuge in Tunneln N2 - Liquefied Natural Gas (LNG) aus regenerativen Quellen, stellt einen potenziellen Kraftstoff für den Schwer- und Fernverkehr des Straßenverkehrs dar. Gegenüber seinen positiven Eigenschaften zu dem in diesem Verkehrssektor häufig verwendeten Kraftstoff Diesel birgt der Kraftstoff aber auch Gefahren für Personen und Bauwerke durch seine sehr niedrige Temperatur bei der Speicherung von ca. -160 °C und seine Explosionsfähigkeit in der Gas-Phase. In der Arbeit wurde sich mit der Gefährdung von Personen und Bauwerken hinsichtlich der von LNG ausgehenden Gefahren in Tunneln auseinandergesetzt. Tunnel stellen besonders schützenswerte Bauwerke dar, da aus vorhergehenden Störfällen in Tunneln bekannt ist, dass diese mit hohen Personen-, Bauwerks-, und Volkswirtschaftlichen-Schäden einhergehen können. Untersuchungsschwerpunkt bei der Bewertung von Gefährdungen durch LNG stellte eine Ereigniskaskade bestehend aus Freisetzung, Verdampfung, Stoffausbreitung und Zündung des sich gebildeten explosionsfähigen LNG-Gas/Luft-Gemisches dar. Mit dem Ziel eine solche Ereigniskaskade realitätsnah vorhersagen und zukünftig hierzu Risikoanalysen durchführen zu können wurden innerhalb der Arbeit Parameterstudien sowie Kalibrierungen und Validierungen gegenüber experimentellen Untersuchungen durchgeführt. Mit den Modellen wurden in der Arbeit exemplarische Fallbeispiele zu Störfällen untersucht. Ergebnisse dieser waren, dass Gefährdungen insbesondere von flüssigem LNG nach dessen Freisetzung und der Verbrennung von LNG-Gas/Luft-Gemischen ausgingen.zeige weniger N2 - Liquefied Natural Gas (LNG) from regenerative sources is a potential fuel for heavy and long-distance road traffic. In contrast to its positive properties compared to diesel, which is often used in this transport sector, the fuel also contains hazards from its very low storage temperature of approx. -160 °C and its explosiveness in the gas phase for personal and structural safety. The dissertation dealt with the dangers to persons and infrastructures according to the hazards by LNG in tunnels. Tunnels are especiallyworth protecting structures since it is known from previous incidents in tunnels that they can go hand in hand with high damage to the people, the structure, and the economy. The main focus of the investigation into the assessment of hazards from LNG was an event cascade consisting of release, evaporation, dispersion, and ignition of the explosive LNG-vapor/air-mixture formed. To realistically predict such an event cascade and being able to carry out risk analyzes for this purpose in the future, parameter studies such as calibrations and validations were carried out concerning experimental investigations. Exemplary case studies on incidents were examined in the thesis with the validated models. The results of this were that there were especially hazards in particular from liquid LNG after its release and the combustion of LNG-vapor/air-mixtures. T2 - Disputation, TU Berlin CY - Berlin, Germany DA - 19.01.2021 KW - Erneuerbare Energien KW - Numerische Strömungsmechanik KW - Sicherheitstechnik KW - Verflüssigtes Erdgas KW - CFD KW - LNG KW - Liquefied Natural Gas KW - Renewable fuels KW - Safety engineering PY - 2021 AN - OPUS4-52119 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hupp, Vitus T1 - Vereinfachte Methoden zur Abschätzung des Brandverhaltens von Haftklebebändern und Haftklebverbindungen N2 - Im Rahmen des laufenden IGF Projektes 20762 N wurde der Einfluss von Haftklebebändern auf das Brandverhalten von Klebverbunden Untersucht. Dabei wurden sowohl kommerziell verfügbare Klebebänder mit unterschiedlichem Brandverhalten als auch Modellhaftklebebänder mit neuartigen Flammschutzmitteln eingesetzt. Zunächst wurde das Brandverhalten der Klebebänder adressiert und anschließend der Einfluss jenes Brandverhaltens auf Brandeigenschaften von entsprechend geklebten Verbunden analysiert. Im Bezug auf die Entflammbarkeit besitzt das Klebeband im Inneren eines Klebverbundes nur einen geringen Einfluss auf das Brandverhalten und die Eigenschaften des Substrates dominieren. Im sich entwickelnden Brand, hier simuliert durch das Cone Calorimeter, sind deutliche Unterschiede zwischen massivem und geklebten Bauteil zu erkennen. Dabei wirkt die Klebfuge je nach Substrat und Klebebandbeschaffenheit unterschiedlich. Weitere Untersuchungen zu flammgeschützten Haftklebstoffen sollen erfolgen und somit neue Wege in der Haftklebstoffentwicklung aufzeigen. T2 - 21. Kolloquium: Gemeinsame Forschung in der Klebtechnik CY - Online meeting DA - 02.03.2021 KW - Haftklebstoff KW - Flammschutz KW - Klebtechnik KW - Klebeband PY - 2021 AN - OPUS4-52226 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Chan, Yin Yam A1 - Ma, C. A1 - Zhou, F. A1 - Hu, Y. A1 - Schartel, Bernhard T1 - Flame retardant flexible polyurethane foams based on phosphorous soybean-oil polyol and expandable graphite N2 - A phosphorous soybean-oil–based polyol was derived via epoxidation and ring opening reaction as an alternative to petrochemical-based polyol for the synthesis of flexible polyurethane foams (FPUFs). 5-wt.% and 10-wt.% of expandable graphite (EG) were added to further improve flame retardancy. The mechanical properties (tensile strength and compression stress) of the foams were investigated. Thermogravimetric analysis (TGA) coupled with Fourier-transform infrared (FTIR) were conducted to evaluate the pyrolysis; limiting oxygen index (LOI), UL 94 and cone calorimeter were performed to analyze the fire performance of the foams; smoke density chamber was used to investigate the smoke released during burning. When 10-wt.% of EG was used, the flame retardancy of the foams was much enhanced due to the synergistic effect between phosphorus and EG. The char yield was three times higher (54wt.%). The fire load MARHE approached 100 kWm−2, half of the value expected for a superposition. The combination of phosphorous polyols and EG is proposed as strategy for future flame retarded FPUFs. KW - Phosphorous soybean-oil–based polyol KW - Flexible polyurethane foam KW - Expandable graphite KW - Flame retardancy KW - Smoke measurement PY - 2021 DO - https://doi.org/10.1016/j.polymdegradstab.2021.109656 SN - 0141-3910 VL - 191 SP - 9656 PB - Elsevier Ltd. AN - OPUS4-52907 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CHAP A1 - Auersch, Lutz ED - Krylov, Victor T1 - Fast trains and isolating tracks on inhomogeneous soils N2 - Methods have been presented for detailed studies of railway vibration and for the fast prediction of train-induced ground vibration. The ground vibration is generated by static or dynamic loads. The main purpose of this contribution was to show the influence of inhomogeneous soils on the different vibration components. Layered soils, namely a soft layer on a stiffer half-space, yield a quite specific transmission behavior. The low-frequency and sometimes also high-frequency cut-off of the transfer function of the soil is demonstrated in theory and by experiments at many sites of which the soil model is approximated from dispersion and transfer function measurements. The layer frequency divides the frequency range in a low-frequency range, where the stiff half-space rules the low amplitudes, and a high amplitude high-frequency range which is mainly determined by the softer top layer. A thick soft layer yields a very low layer frequency, so that the higher soft soil amplitudes have a wider range down to low frequencies. A thin layer yields a high layer frequency, so that the high frequencies above this layer frequency are dominant. The higher the contrast between the stiff half-space and the soft layer is, the stronger the increase between the half-space and layer amplitudes, the more characteristic are the spectra of the soil transfer function. The range of measured soils has been from vS1 down to 125 m/s, vS2 up to 1000 m/s and the layer frequencies are within 10 Hz < f0 < 75 Hz. Moreover, during this measuring campaign in Switzerland, all 11 sites showed clearly the layer-on-half-space behaviour. The transfer functions of inhomogeneous soils have been used to predict the ground vibration due to dynamic axle loads which is usually thought to be the most important component. The passage of static loads, in the contrary, results in very small vibration amplitudes for low train speeds, which can only be found at near distances and at low frequencies. They attenuate very rapidly with distance and lose very rapidly the higher frequency content. The passage of static axle loads can be included in the prediction of railway vibration just for completeness. Special attention should be given to the case if the train runs with the Rayleigh-wave speed of the soil (Rayleigh train). The Rayleigh-train effect is strongest for a homogeneous half-space: At the near-field of the track the amplitudes are raised strongly compared to normal trains, and in addition, little attenuation with distance is observed. In case of a layered soil, the low-frequency cut-off reduces the frequency range and the amplitudes of the homogeneous quasi-static ground vibrations. Therefore, the Rayleigh-train effects are clearly reduced by a layered soil and they disappear if the layer frequency (for example for a thin layer) is higher than the frequency band of the axle impulse. The Rayleigh-train effect could completely disappear in a randomly inhomogeneous soil, but this has not been analysed so far. The axle impulses from static loads can have an additional, quite different effect. They can be scattered by a randomly inhomogeneous soil so that a part (the scattered part) of the axle impulse can reach further distances from the track. This can establish a certain mid-frequency component of the ground vibration which becomes dominant in the far-field, and this important component exists for all train speeds. Experimental results from BAM and international measurements show the importance of the corresponding frequency range. The mitigation of train induced ground vibration by elastic and stiff track elements has been analysed threefold. The vehicle-track interaction yields the reduction at high frequencies above the vehicle-track resonance. This is the standard effect. The filtering of trackbed errors by the bending stiffness of the track yields a certain mid-frequency effect. An even stronger mid-frequency effect is predicted for the mitigation of the scattered axle impulses by the bending stiffness and elastic elements of the track. KW - Ground vibration KW - Inhomogeneous soils KW - Train excitation KW - Prediction KW - Mitigation KW - Layered soils KW - Soft track elements KW - Track beam KW - Scattered axle impulses KW - Wavenumber method KW - Multi-beam method PY - 2019 SN - 978-0-7277-6379-2 DO - https://doi.org/10.1680/gvfhsr.63792.027 SP - Chapter 2, 27 EP - 75 PB - ICE Publishing CY - London ET - 1 AN - OPUS4-48432 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bäßler, Ralph A1 - Le, Quynh Hoa A1 - Yevtushenko, Oleksandra A1 - Bettge, Dirk T1 - Corrosion Aspects for Materials to be Used in CC(U)S Applications N2 - This contribution provides current findings regarding materials susceptibility for carbon capture, utilization and storage (CCUS) applications. Basing on results gathered in 2 German long-term projects (COORAL and CLUSTER) suitable materials are introduced as well as dominating impurities of the CO2-stream and corrosion mechanisms. Investigations cover the whole CCUS process chain and provide material recommendations for certain parts. T2 - 1st International Conference on Corrosion Protection and Application CY - Chongqing, China DA - 09.10.2019 KW - Carbon KW - Capture KW - Storage KW - Utilization KW - CCS KW - CCU KW - CO2 KW - Corrosion KW - Steel PY - 2019 SP - Paper 31 PB - Chinese Society for Corrosion and Protection CY - Chongqing/China AN - OPUS4-49301 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bäßler, Ralph T1 - Corrosion Aspects for Materials to be Used in CC(U)S Applications N2 - This contribution provides current findings regarding materials susceptibility for carbon capture, utilization and storage (CCUS) applications. Basing on results gathered in 2 German long-term projects (COORAL and CLUSTER) suitable materials are introduced as well as dominating impurities of the CO2-stream and corrosion mechanisms. Investigations cover the whole CCUS process chain and provide material recommendations for certain parts. T2 - 1st International Conference on Corrosion Protection and Application CY - Chongqing, China DA - 09.09.2019 KW - Carbon KW - Capture KW - Storage KW - Utilization KW - CCS KW - CCU KW - CO2 KW - Corrosion PY - 2019 AN - OPUS4-49302 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Bäßler, Ralph T1 - Book review: Dictionary of Metallurgy and Metal Processing - English-German – German-English N2 - The first issue of this classic dictionary contains highly specialized terms, not only of the area of metallurgy but also of welding, soldering and corrosion. Special attention was paid by the author to a correct reference of each term according to the field of application. Finally, this book fulfills the intension of its author, to collect relevant terms with the correct pendant from a huge variety of sources and applications. It provides the user a foundation for correct terminology and communication for international contacts. KW - Metallurgy KW - Processing PY - 2019 DO - https://doi.org/10.1002/maco.201970104 SN - 1521-4176 SN - 0947-5117 VL - 70 IS - 11 SP - 1919 PB - WILEY‐VCH Verlag GmbH & Co. KGaA CY - Weinheim AN - OPUS4-49304 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Erning, Johann Wilhelm A1 - Gerhardy, K. T1 - Anschluss von Feuerlöschanlagen N2 - Die Ergebnisse des Diskurses zu den Möglichkeiten des Anschlusses von Feuerlöschanlagen an die öffentliche Trinkwasserverordnung werden zusammengefasst und beleuchtet. Grenzen der Anwendung werden beschrieben, Risiken dargestellt. KW - Absicherung KW - Trinkwasser KW - Feuerlöschen PY - 2019 SN - 1436-6134 VL - 2019 IS - 9 SP - 26 EP - 29 PB - wvgw Wirtschafts- und Verlagsgesellschaft Gas und Wasser mbH CY - Bonn AN - OPUS4-49277 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schneider, Ronald T1 - Effect of repair models on risk based optimal inspection strategies for support structures of offshore wind turbines N2 - Owners or operators of offshore wind farms perform inspections to collect information on the condition of the wind turbine support structures and perform repairs if required. These activities are costly and should be optimized. Risk-based methods can be applied to identify inspection and repair strategies that ensure an optimal balance between the expected total service life cost of inspection and repair, and the achieved risk reduction. Such an optimization requires explicit modeling of repairs. In this paper, the impact of different repair models on the results of a risk-based optimization of inspection and repair strategies is quantified in a numerical example considering a jacket-type steel frame subject to high-cycle fatigue. The example showed that, in this specific application, there is no need for detailed modeling of the behavior of repaired welded connections. T2 - 5th International Conference on Smart Monitoring, Assessment and Rehabilitation of Civil Structures (SMAR 2019) CY - Potsdam, Germany DA - 27.08.2019 KW - Risk KW - Reliability KW - Inspection planning KW - Offshore wind turbines PY - 2019 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-488297 UR - https://www.smar2019.org/Portals/smar2019/bb/Th.2.A.4.pdf SP - Paper Th.2.A.4, 1 EP - 8 AN - OPUS4-48829 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schneider, Ronald T1 - Effect of repair models on risk based optimal inspection strategies for support structures of offshore wind turbines N2 - Owners or operators of offshore wind farms perform inspections to collect information on the condition of the wind turbine support structures and perform repairs if required. These activities are costly and should be optimized. Risk-based methods can be applied to identify inspection and repair strategies that ensure an optimal balance between the expected total service life cost of inspection and repair, and the achieved risk reduction. Such an optimization requires explicit modeling of repairs. In this paper, the impact of different repair models on the results of a risk-based optimization of inspection and repair strategies is quantified in a numerical example considering a jacket-type steel frame subject to high-cycle fatigue. The example showed that, in this specific application, there is no need for detailed modeling of the behavior of repaired welded connections. T2 - 5th International Conference on Smart Monitoring, Assessment and Rehabilitation of Civil Structures (SMAR 2019) CY - Potsdam, Germany DA - 27.08.2019 KW - risk, reliability, inspection planning, offshore wind turbines PY - 2019 AN - OPUS4-48830 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Markwart, J. C. A1 - Battig, Alexander A1 - Velencoso, M. M. A1 - Pollok, D. A1 - Schartel, Bernhard A1 - Wurm, F. R. T1 - Aromatic vs. Aliphatic Hyperbranched Polyphosphoesters as Flame Retardants in Epoxy Resins N2 - The current trend for future flame retardants (FRs) goes to novel efficient halogen-free materials, due to the ban of several halogenated FRs. Among the most promising alternatives are phosphorus-based FRs, and of those, polymeric materials with complex shape have been recently reported. Herein, we present novel halogen-free aromatic and aliphatic hyperbranched polyphosphoesters (hbPPEs), which were synthesized by olefin Metathesis polymerization and investigated them as a FR in epoxy resins. We compare their efficiency (aliphatic vs. aromatic) and further assess the differences between the monomeric compounds and the hbPPEs. The decomposition and vaporizing behavior of a compound is an important factor in its flame-retardant behavior, but also the interaction with the pyrolyzing matrix has a significant influence on the performance. Therefore, the challenge in designing a FR is to optimize the chemical structure and its decomposition pathway to the matrix, with regards to time and temperature. This behavior becomes obvious in this study, and explains the superior gas phase activity of the aliphatic FRs. KW - Phosphorus KW - Metathesis KW - Dendritic KW - Cone calorimeter KW - Fire test PY - 2019 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-494535 DO - https://doi.org/10.3390/molecules24213901 SN - 1420-3049 VL - 24 IS - 21 SP - 3901 PB - MDPI AN - OPUS4-49453 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Battig, Alexander A1 - Markwart, J. C. A1 - Wurm, F. R. A1 - Schartel, Bernhard T1 - Matrix matters: Hyperbranched flame retardants in aliphatic and aromatic epoxy resins N2 - We synthesized a library of phosphorus-based flame retardants (phosphates and phosphoramides of low and high molar mass) and investigated their behavior in two epoxy resins (one aliphatic and one aromatic). The pyrolytic and burning behavior of the two resins (via TGA, TG-FTIR, Hot stage FTIR, Py-GC/MS, PCFC, DSC, LOI, UL-94, Cone calorimeter) are analyzed and compared to the results of flame retardant (FR)-containing composites. A decomposition pathway incorporating the identified modes of action and known chemical mechanisms is proposed. The overlap of decomposition temperature (Tdec) ranges of matrix and FR determines the efficacy of the system. Low molar mass FRs strongly impact material properties like Tg but are very reactive, and high molar mass variants are more thermally stable. Varying PeO and PeN content of the FR affects decomposition, but the chemical structure of the matrix also guides FR behavior. Thus, phosphates afford lower fire load and heat release in aliphatic epoxy resins, and phosphoramides can act as additives in an aromatic matrix or a reactive FRs in aliphatic ones. The chemical structure and the structure-property relationship of both FR and matrix are central to FR performance and must be viewed not as two separate but as one codependent system. KW - Flame retardant KW - Phosphate KW - Phosphoramide KW - Epoxy resin KW - Hyperbranched polymer PY - 2019 DO - https://doi.org/10.1016/j.polymdegradstab.2019.108986 SN - 0141-3910 VL - 170 SP - 108986 PB - Elsevier Ltd. AN - OPUS4-49456 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Günther, Martin T1 - Bubbles and Collapses: Fire Phenomena of Polyurethane Foams N2 - This work investigates the fire phenomena of rigid polyurethane foams (RPUFs) in detail. To elucidate structure-property relationships, systematically varied sets of materials were prepared covering polyurethane, polyisocyanurate-polyurethane and flame retarded polyurethane foams. Advanced cone calorimeter investigations provide insight into the fire behavior under forced flaming conditions. Thermocouples inside specimens give information about the temperature gradient during combustion. Furthermore, fire phenomena were characterized using cross sections of quenched samples and the scanning electron microscope. By using a Multi methodological approach and systematically varied sets of foam materials, new insights into the burning of RPUFs were won. For the flame retarded foams, the dominant flame retardant mode of action changed with density. PIR foams exhibited a cellular structure in the residue leading to the superior fire performance compared to polyurethane foams. The understanding of fire phenomena contributes to future development of tailored flame retardant strategies for RPUFs. T2 - AOFSM’3, 3rd Asia-Oceania Symposium for Fire Safety Materials Science and Engineering CY - Shanghai, China DA - 24.10.2019 KW - PU-Foam KW - Fire behaviour PY - 2019 AN - OPUS4-49457 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Burkert, Andreas T1 - Korrosionsuntersuchungen in Erdböden N2 - Das Verhalten von Erdböden gegenüber metallenen Konstruktionswerkstoffen ähnelt in vielen Fällen der von neutralen Wässern. Der in natürlichen Erdböden vorhandene Wasseranteil bildet mit den löslichen Inhaltsstoffen eine Elektrolytlösung. Eine merkbare Korrosionsgeschwindigkeit tritt erst dann auf, wenn der Boden einen bestimmten Wassergehalt aufweist, der eine Sauerstoffdiffusion im Boden zur Oberfläche des Metalls gewährleistet. Von maßgebendem Einfluss auf die korrosionsverursachende Wirkung der Böden ist neben dem Feuchtegehalt, der die Leitfähigkeit des Bodens bestimmt, der pH-Wert. Verschiedene Bodenarten besitzen unterschiedliche Wasser- und Sauerstoffdurchlässigkeiten, sowie Unterschiede der gelösten Inhaltsstoffe wie Chloride oder Sulfate, wodurch sich das Korrosionsverhalten von Metallen in verschiedenen Böden stark unterscheidet. In der DIN 50929-3 werden Böden in vier verschiedene Bodenklassen mit Korrosionsbelastungen von sehr niedrig bis hoch unterteilt. Durch verschiedene Bodenanalysen und örtliche Gegebenheiten kann nach DIN 50929-3 zwar die Korrosivität eines Bodens bestimmt werden, jedoch ist die Reproduzierbarkeit eines Bodens (Prüfmediums) praktisch nicht möglich. Es gibt jedoch Überlegungen, wie die Einstellung einer Bodenklasse durch Verwendung von Normsand und der Zugabe von Stoffen erzielt werden kann, wodurch die Reproduzierbarkeit eines Bodens ermöglicht wird. T2 - 13. Sitzung des NA 062 01 77 AA „Korrosionsprüfverfahren“ CY - Neuss, Germany DA - 24.10.2019 KW - Korrosion KW - Böden KW - DIN 50929-3 KW - Zink KW - Soil KW - Zinc PY - 2019 AN - OPUS4-49459 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz ED - Lombaert, G. ED - Degrande, G. T1 - Predicted and measured amplitude-speed relations of railway ground vibrations at four German sites with different test trains N2 - The present contribution evaluates four measuring series made by the Federal Institute of Material Research and Testing for the relations between train speed and ground vibration amplitudes. This experimental evaluation is supported by the simulation of the train passages at the different sites by using appropriate excitation mechanisms and forces as well as layered soil models which have been derived from impact measurements at each site. T2 - 13th International Workshop on Railway Noise and Vibration CY - Leuven, Belgium DA - 16.09.2019 KW - Train speed KW - Ground vibration KW - Excitation forces KW - Layered soils PY - 2019 SP - 1 EP - 8 PB - KU Leuven CY - Leuven AN - OPUS4-49440 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz ED - Adam, C. T1 - Bahnerschütterungen bei verschiedenen Böden und Zuggeschwindigkeiten – Messungen in Deutschland, Österreich und der Schweiz N2 - Die Bundesanstalt für Materialforschung und -prüfung hat in den letzten 30 Jahren an vielen Orten Bahnerschütterungen gemessen. Dabei wurden immer auch Versuche zur Bestimmung der Bodeneigen-schaften durchgeführt, meist mit Hammeranregung, gelegentlich auch mit Schwingeranregung. Es werden verschiedene Auswertemethoden wie Seismogramm-Montage, Spektrale Analyse (SASW), Multistation Analysis of Surface Waves (MASW), f,v-Analyse (Dispersion aus zweifacher Fourier-Analyse), Spatial AutoCorrelation (SPAC, hier auch für deterministische Quellen) vorgestellt. Durch Approximation der frequenzabhängigen Wellengeschwindigkeiten (Dispersion) oder der gemessenen Übertragungsfunktionen erhält man ein passendes Bodenmodell. Zu diesem Bodenmodell kann man dann die Übertragungsfunktionen für Hammer- und Zuganregung berechnen. Mit allgemeinen oder spezifischen Achslastspektren werden dann die Bahnerschütterungen prognostiziert und mit den Messergebnissen verglichen. Bei etlichen Messorten, insbesondere in der Schweiz, wurden deutliche Merkmale einer Bodenschichtung beobachtet. Es ergibt sich eine deutliche Reduktion der tiefen Frequenzanteile durch den steifen unterliegenden Halbraum. Die weiche Deckschicht bestimmt das hochfrequente Verhalten. Hier bewirkt die Materialdämpfung des Bodens oft einen starken Amplitudenabfall, sowohl mit der Entfernung als auch mit der Frequenz. Für den verbleibenden mittelfrequenten Anteil wurde an mehreren Messorten die Amplituden-Fahrgeschwindigkeits-Gesetzmäßigkeiten untersucht. Es gibt konstante bis stark ansteigende Amplituden, und es zeigt sich auch hier, dass der geschichtete Boden von entscheidender Bedeutung ist. T2 - 16. D-A-CH Tagung Erdbebeningenieurwesen & Baudynamik (D-A-CH 2019) CY - Innsbruck, Austria DA - 26.09.2019 KW - Wellengeschwindigkeit KW - Dispersionsmessung KW - Bodenübertragungsfunktion KW - Bahnerschütterungen KW - Zuggeschwindigkeit PY - 2019 SP - 1 EP - 8 PB - Universität Innsbruck CY - Innsbruck AN - OPUS4-49441 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz T1 - Predicted and measured amplitude-speed relations of railway ground vibrations at four German sites with different test trains N2 - The present contribution evaluates four measuring series made by the Federal Institute of Material Research and Testing for the relations between train speed and ground vibration amplitudes. This experimental evaluation is supported by the simulation of the train passages at the different sites by using appropriate excitation mechanisms and forces as well as layered soil models which have been derived from impact measurements at each site. T2 - 13th International Workshop on Railway Noise and Vibration CY - Leuven, Belgium DA - 16.09.2019 KW - Excitation forces KW - Train speed KW - Ground vibration KW - Layered soils PY - 2019 AN - OPUS4-49444 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz T1 - Bahnerschütterungen bei verschiedenen Böden und Zuggeschwindigkeiten – Messungen in Deutschland, Österreich und der Schweiz N2 - Die Bundesanstalt für Materialforschung und -prüfung hat in den letzten 30 Jahren an vielen Orten Bahnerschütterungen gemessen. Dabei wurden immer auch Versuche zur Bestimmung der Bodeneigen-schaften durchgeführt, meist mit Hammeranregung, gelegentlich auch mit Schwingeranregung. Es werden verschiedene Auswertemethoden wie Seismogramm-Montage, Spektrale Analyse (SASW), Multistation Analysis of Surface Waves (MASW), f,v-Analyse (Dispersion aus zweifacher Fourier-Analyse), Spatial AutoCorrelation (SPAC, hier auch für deterministische Quellen) vorgestellt. Durch Approximation der frequenzabhängigen Wellengeschwindigkeiten (Dispersion) oder der gemessenen Übertragungsfunktionen erhält man ein passendes Bodenmodell. Zu diesem Bodenmodell kann man dann die Übertragungsfunktionen für Hammer- und Zuganregung berechnen. Mit allgemeinen oder spezifischen Achslastspektren werden dann die Bahnerschütterungen prognostiziert und mit den Messergebnissen verglichen. Bei etlichen Messorten, insbesondere in der Schweiz, wurden deutliche Merkmale einer Bodenschichtung beobachtet. Es ergibt sich eine deutliche Reduktion der tiefen Frequenzanteile durch den steifen unterliegenden Halbraum. Die weiche Deckschicht bestimmt das hochfrequente Verhalten. Hier bewirkt die Materialdämpfung des Bodens oft einen starken Amplitudenabfall, sowohl mit der Entfernung als auch mit der Frequenz. Für den verbleibenden mittelfrequenten Anteil wurde an mehreren Messorten die Amplituden-Fahrgeschwindigkeits-Gesetzmäßigkeiten untersucht. Es gibt konstante bis stark ansteigende Amplituden, und es zeigt sich auch hier, dass der geschichtete Boden von entscheidender Bedeutung ist. T2 - 16. D-A-CH Tagung Erdbebeningenieurwesen & Baudynamik (D-A-CH 2019) CY - Innsbruck, Austria DA - 26.09.2019 KW - Zuggeschwindigkeit KW - Wellengeschwindigkeit KW - Dispersionsmessung KW - Bodenübertragungsfunktion KW - Bahnerschütterungen PY - 2019 AN - OPUS4-49445 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz T1 - Four typical errors in train induced ground vibration and ground vibration mitigation N2 - Mitigation measures of railway induced vibration have been demonstrated at the emission, transmission and immission part. It must be carefully observed that the correct masses and stiffnesses are used. Typical mistakes have been shown, - 1D models for vehicle-track interaction, - impedance instead of stiffness for the infill material of a trench, - rigid buildings or neglecting the soil-building interaction. The dominant mid-frequency part of the ground vibration is due to the irregular soil. T2 - ISO/TC 108/SC 2/WG 8 Working group Ground-borne noise and vibration from rail systems CY - Milano, Italy DA - 14.10.2019 KW - Ground vibration KW - Train excitation KW - Mitigation PY - 2019 AN - OPUS4-49446 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz T1 - Berechnung und Beeinflussung von Deckeneigenfrequenzen N2 - Es werden Erfahrungen zur Berechnung von Deckeneigenfrequenzen aus zahlreichen Projekten zusammengetragen. T2 - Projektbesprechung zum Hotelneubau CY - Berlin, Germany DA - 10.07.2019 KW - Deckeneigenfrequenzen PY - 2019 AN - OPUS4-49448 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Battig, Alexander A1 - Markwart, J. C. A1 - Wurm, F. R. A1 - Schartel, Bernhard T1 - Hyperbranched phosphorus flame retardants: multifunctional additives for epoxy resins N2 - We successfully synthesized multifunctional P-based hyperbranched polymeric flame retardants (hb-FRs) with varying oxygen-to-nitrogen (O : N) content and characterized them via 1H and 31P NMR and GPC. Their miscibility in epoxy resins (EP) and impact on glass-transition temperatures (Tg) were determined via differential scanning calorimetry (DSC). Using thermogravimetric and evolved gas Analysis (TGA, TG-FTIR), pyrolysis gas chromatography/mass spectrometry (Py-GC-MS), hot stage FTIR, flammability tests UL-94 and LOI, fire testing via cone calorimetry, residue analysis via scanning electron microscopy (SEM) and elemental analysis, detailed decomposition mechanisms and modes of action are proposed. hb-polymeric FRs have improved miscibility and thermal stability, leading to high FR performance even at low loadings. Polymeric, complex FRs increase flame retardancy, mitigate negative effects of low molecular weight variants, and can compete with commercial aromatic FRs. The results illustrate the role played by the chemical structure in flame retardancy and highlight the potential of hb-FRs as multifunctional additives. KW - Flame retardant KW - Hyperbranched PY - 2019 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-486589 DO - https://doi.org/10.1039/c9py00737g SN - 1759-9962 SN - 1759-9954 VL - 10 IS - 31 SP - 4346 EP - 4358 PB - RSC AN - OPUS4-48658 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kauss, Norman A1 - Heyn, A. A1 - Halle, T. A1 - Rosemann, Paul T1 - Detection of sensitisation on aged lean duplex stainless steel with different electrochemical methods N2 - Ageing at 600 °C (from 0.1 h up to 20 h) leads to the formation of precipitations at the ferrite-ferrite (α/α) and ferrite-austenite (α/γ) grain boundaries of the lean duplex stainless steel (LDSS) X2CrNiN22-2. This leads to sensitisation due to chromium depletion and decreased pitting corrosion resistance proven by the results of various electrochemical methods (DL-EPR and determination of CPT, Epit). These results were compared with the KorroPad method, which uses an agar-based gel-electrolyte for the detection of stainless steel surfaces prone to pitting corrosion. However, the standard configuration of the KorroPad showed no differentiation for the various ageing conditions. Therefore, modified versions of the KorroPad with two, five and ten times higher NaCl and potassium ferrocyanide III (K3[Fe(CN)6]) concentrations were successfully used to visualise the behaviour detected by DL-EPR, Epit and CPT. Therefore, the KorroPad method can also detect a microstructure related reduction of pitting corrosion resistance, which can drastically reduce the experimental effort to generate sensitisation diagrams for stainless steels. KW - Lean duplex KW - Stainless steel KW - Sensitisation KW - Polarisation KW - Critical pitting temperature KW - Pitting corrosion KW - KorroPad KW - Ageing treatment PY - 2019 DO - https://doi.org/10.1016/j.electacta.2019.05.081 SN - 0013-4686 SN - 1873-3859 VL - 317 SP - 17 EP - 24 PB - Elsevier AN - OPUS4-48374 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Sanchez-Olivares, G. A1 - Rabe, Sebastian A1 - Pérez-Chávez, R. A1 - Calderas, F. A1 - Schartel, Bernhard T1 - Industrial-waste agave fibres in flame-retarded thermoplastic starch biocomposites N2 - Flame-retarded biocomposites of thermoplastic starch and natural fibres are successfully processed according to state-of-the-art extrusion and injection moulding. Using agave fibres and henequen fibres recovered from local industrial waste is a convincing contribution to sustainability. A systematically varied set of biocomposites is investigated comprehensively, e.g. electron microscopy is used for characterizing the morphology, rheology for the melt viscosity, tensile and impact resistance for the mechanical properties, thermal analysis for the pyrolysis, UL 94 burning chamber and oxygen index for the flammability, and cone calorimeter for the fire behaviour. Achieving sufficient mechanical properties was not the goal in our pre-competitive study but may be tackled by adding compatibilizer in future. The combination of well-dispersed natural fibres, aluminium diethylphosphinate (AlPi) and a special silicone synergist (Si) is proposed as promising innovative route for V-classified biocomposites. The flame-retardancy modes of action in the gas phase (fuel dilution and flame inhibition) and in the condensed phase (charring, protective layer formation) are discussed in detail, as is the role of combining the ingredients. This work is a convincing proof of principle of how to prepare industrial-waste fibres biocomposites, to apply the synergistic combination of AlPi and Si for future flame-retarded technical polymer materials that are based on renewable resources and compostable. KW - Flame-retardant biocomposites KW - Natural fibre KW - Biopolymer KW - Sustainability KW - Industrial-waste fibres KW - Flammability PY - 2019 DO - https://doi.org/10.1016/j.compositesb.2019.107370 SN - 1359-8368 VL - 177 SP - 107370 PB - Elsevier Ltd. AN - OPUS4-48777 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Rastayesh, S. A1 - Long, Lijia A1 - Sørensen, J. D. A1 - Thöns, Sebastian T1 - Risk Assessment and Value of Action Analysis for Icing Conditions of Wind Turbines Close to Highways N2 - The paper presents research results from the Marie Skłodowska-Curie Innovative Training Network INFRASTAR in the field of reliability approaches for decision-making for wind turbines and bridges. This paper addresses the application of Bayesian decision analysis for installation of heating systems in wind turbine blades in cases where an ice detection system is already installed in order to allow wind turbines to be placed close to highways. Generally, application of ice detection and heating systems for wind turbines is very relevant in cases where the wind turbines are planned to be placed close to urban areas and highways, where risks need to be considered due to icing events, which may lead to consequences including human fatality, functional disruptions, and/or economic losses. The risk of people being killed in a car passing on highways near a wind turbine due to blades parts or ice pieces being thrown away in cases of overicing is considered in this paper. The probability of being killed per kilometer and per year is considered for three cases: blade parts thrown away as a result of a partial or total failure of a blade, ice thrown away in two cases, i.e., of stopped wind turbines and of wind turbines in operation. Risks due to blade parts being thrown away cannot be avoided, since low strengths of material, maintenance or manufacturing errors, mechanical or electrical failures may result in failure of a blade or blade part. The blade (parts) thrown away from wind turbines in operation imply possible consequences/fatalities for people near the wind turbines, including in areas close to highways. Similar consequences are relevant for ice being thrown away from wind turbine blades during icing situations. In this paper, we examine the question as to whether it is valuable to put a heating System on the blades in addition to ice detection systems. This is especially interesting in countries with limited space for placing wind turbines; in addition, it is considered if higher power production can be obtained due to less downtime if a heating system is installed. KW - Risk assessment KW - Value of action analysis KW - Icing conditions KW - Wind turbine KW - Blade PY - 2019 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-487805 DO - https://doi.org/10.3390/en12142653 VL - 12 IS - 14 SP - 2653-1 EP - 2653-15 PB - MDPI AN - OPUS4-48780 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Munasir, A1 - Triwikantoro, A1 - Zainuri, M. A1 - Bäßler, Ralph A1 - Darminto, T1 - Corrosion Polarization Behavior of Al-SiO2 Composites in 1M NaCl and Related Microstructural Analysis N2 - The composites combining aluminum and silica nanoparticles with the addition of tetramethylammonium hydroxide (Al-SiO2(T)) and butanol (Al-SiO2(B)) as mixing media have been successfully fabricated. Corrosion behavior of Al-SiO2 composites before and after exposure in 1M NaCl solution was examined using potentiodynamic polarization (Tafel curve analysis). The study was also equipped with scanning electron microscopy (SEM), energy dispersive X-ray (EDX), and X-ray diffraction (XRD) investigations. Before exposure, Al-SiO2(T) exhibited the best corrosion resistance. Performance improvement was indicated by Al-SiO2(B) up to 10 times better than Al-SiO2(T) after exposure. The increased SiO2 content did not significantly enhance the corrosion resistance of the composites. The Al-SiO2 composites with 5% SiO2 content showed very high corrosion resistance (as the optimum composition). Furthermore, pitting corrosion was observed in the Al-SiO2 composites, indicated by the formation of corrosion products at grain boundaries. The product was affected by the presence of SiO2 in the Al matrix and the NaCl environment at 90 °C (approach to synthetic geothermal media: Na+, Cl, H+, OH-). Our study revealed the presence of γ-Al2O3, γ-Al(OH)3, and Al(OH)2Cl as the dominant corrosion products. KW - Al-Composite KW - Corrosion KW - Corrosion rate KW - SiO2 Nanoparticle KW - Tafel Plot PY - 2019 DO - https://doi.org/10.5829/ije.2019.32.07a.11 SN - 1025-2495 SN - 1735-9244 VL - 7 IS - 32 SP - 982 EP - 990 PB - Materials and Energy Research Center AN - OPUS4-48742 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Angst, U.M. A1 - Geiker, M.R. A1 - Alonso, M.C. A1 - Polder, R. A1 - Isgor, O.B. A1 - Elsener, B. A1 - Wong, H. A1 - Michel, A. A1 - Hornbostel, K. A1 - Gehlen, C. A1 - François, R. A1 - Sanchez, M. A1 - Criado, M. A1 - Sørensen, H. A1 - Hansson, C. A1 - Pillai, R. A1 - Mundra, Shishir A1 - Gulikers, J. A1 - Raupach, M. A1 - Pacheco, J. A1 - Sagüés, A. T1 - The effect of the steel-concrete interface on chloride-induced corrosion initiation in concrete: a critical review by RILEM TC 262-SCI N2 - The steel–concrete interface (SCI) is known to influence corrosion of steel in concrete. However, due to the numerous factors affecting the SCI—including steel properties, concrete properties, execution, and exposure conditions—it remains unclear which factors have the most dominant impact on the susceptibility of reinforced concrete to corrosion. In this literature review, prepared by members of RILEM technical committee 262-SCI, an attempt is made to elucidate the effect of numerous SCI characteristics on chloride-induced corrosion initiation of steel in concrete. We use a method to quantify and normalize the effect of individual SCI characteristics based on different literature results, which allows comparing them in a comprehensive context. It is found that the different SCI characteristics have received highly unbalanced research attention. Parameters such as w/b ratio and cement type have been studied most extensively. Interestingly, however, literature consistently indicates that those parameters have merely a moderate effect on the corrosion susceptibility of steel in concrete. Considerably more pronounced effects were identified for (1) steel properties, including metallurgy, presence of mill scale or rust layers, and surface roughness, and (2) the moisture state. Unfortunately, however, these aspects have received comparatively little research attention. Due to their apparently strong influence, future corrosion studies as well as developments towards predicting corrosion initiation in concrete would benefit from considering those aspects. Particularly the working mechanisms related to the moisture conditions in microscopic and macroscopic voids at the SCI is complex and presents major opportunities for further research in corrosion of steel in concrete. KW - Steel-concrete interface KW - Interfacial transition zone KW - Durability KW - Corrosion KW - Inhomogeneity KW - Variability PY - 2019 DO - https://doi.org/10.1617/s11527-019-1387-0 VL - 52 IS - 4 SP - 88-1 EP - 88-25 PB - Springer Nature AN - OPUS4-48689 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Babutzka, Martin T1 - Investigation of the salinization in marine and offshore environment - test methods and challenges N2 - Salinization and contamination of metal surfaces by chloride-containing aerosols is of great importance with regard to corrosion phenomena in the maritime sector and in offshore applications. Especially Offshore Wind Turbines are exposed to extreme corrosive conditions due to high chloride concentrations in the atmosphere and the resulting high chloride deposition rates. It is of great importance to evaluate to what extent salinization of the surface influences the corrosion protection of coatings and pitting occurrence on stainless steels under atmospheric conditions to evaluate the durability of metallic building structures in offshore and marine environments. The evaluation of the scientific literature and regulatory guidelines has shown that there are still many open questions regarding the contamination of metal surfaces by chlorides. This contribution will discuss how salinization of metal surfaces is evaluated and monitored according to current standards and guidelines. Future challenges concerning test methods and the application of evaluated salinization values and deposition rates will be discussed. T2 - 5th International Conference on Smart Monitoring, Assessment and Rehabilitation of Civil Structures CY - Potsdam, Germany DA - 27.08.2019 KW - Maritime Atmosphäre KW - Versalzung KW - Maritime atmosphere KW - Salinization PY - 2019 AN - OPUS4-48787 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Faes, W. A1 - Lecompte, S. A1 - van Bael, J. A1 - Salenbien, R. A1 - Bäßler, Ralph A1 - Bellemans, I. A1 - Cools, P. A1 - de Geyter, N. A1 - Morent, R. A1 - Verbeken, K. A1 - de Paepe, M. T1 - Corrosion behaviour of different steel types in artificial geothermal fluids N2 - Geothermal energy is an interesting alternative to polluting fossil energy sources. Therefore, in Belgium, two wells have been drilled for a deep geothermal power plant. However, the environment to which the installations are exposed is challenging. The geothermal brine has 165 g/l total dissolved solids (of which 90% are sodium and chlorine) and the production temperature can be up to 130 °C. To assess their suitability to be used in a geothermal power plant, the corrosivity of the artificial brine to three common construction materials was investigated with exposure and electrochemical tests. The metals under consideration are a low-alloyed carbon steel (S235JR), an austenitic stainless steel (UNS S31603) and a duplex stainless steel (UNS S31803). The carbon steel, that was found to corrode uniformly, could be considered as a constructional material if a sufficient wall thickness is chosen. The austenitic stainless steel and the duplex stainless steel demonstrate very low uniform corrosion rates. They are however susceptible to pitting and crevice corrosion. To guarantee safe operation of the geothermal power plant, the susceptibility of the alloys to stress corrosion cracking should be tested and in situ experiments should be performed. KW - Geothermal energy KW - Corrosion KW - Carbon dioxide KW - Carbon steel KW - Stainless steel PY - 2019 DO - https://doi.org/10.1016/j.geothermics.2019.05.018 SN - 0375-6505 VL - 82 IS - 11 SP - 182 EP - 189 PB - Elsevier Ltd. AN - OPUS4-48759 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Munasir, A1 - Triwikantoro, A1 - Zainuri, M. A1 - Bäßler, Ralph A1 - Darminto, T1 - Mechanical Strength and Corrosion Rate of Aluminium Composites (Al/SiO2): Nanoparticle Silica (NPS) as Reinforcement N2 - The fabrication and characteristics of amorphous silica reinforced Al matrix composites are studied in this paper. The major starting materials were commercial Al powder and extracted nanoparticle SiO2 (NPS) powder from Indonesian silica sands. Two different active solutions,namely N-butanol and tetramethylammonium hydroxide (TMAH), were introduced during synthesis. Characterisations in terms of physical, mechanical, microstructural and corrosion rate examinations were also employed. Introducing the SiO2 nanoparticles into the Al matrix has decreased the density and increased the porosity of the composites. The addition of N-butanol into Al/SiO2(Al/SiO2(B)) led to broader and lower X-ray diffraction profiles than the addition of TMAH (Al/SiO2(T)). From the microstructural analysis, we found that the SiO2 particles enter and agglomerate into the opening gap of the Al sheets. Furthermore, yield strength, ultimate compression strength and modulus of elasticity tended to reduce the addition of SiO2. The corrosion rate of Al/SiO2(T) was lower than that of Al/SiO2(B) composites. KW - Aluminium KW - Silica KW - Al/SiO2 composite KW - Mechanical strength KW - Corrosion rate PY - 2019 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-487185 DO - https://doi.org/10.21315/jps2019.30.1.7 SN - 1675-3402 SN - 2180-4230 VL - 30 IS - 1 SP - 81 EP - 97 PB - USM Press CY - Pulau Pinang, Malaysia AN - OPUS4-48718 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Beck, Joana T1 - Review: Fitz's Atlas™of coating surveys N2 - Fitz's Atlas of coating surveys is designed as loose‐leave binder with a resistant cover that not only provides the possibility of updating the Atlas easily but also makes it practicable for on‐site use. This binder is well structured by sheet dividers with tabs for each of the 16 chapters. All in all, this atlas supports the surveyor by giving practicable hints and advice, lists and pictures to prepare and conduct investigations and write surveys. KW - Coating KW - Survey KW - Protection PY - 2019 DO - https://doi.org/10.1002/maco.201970084 SN - 1521-4176 SN - 0947-5117 VL - 70 IS - 8 SP - 1508 PB - Wiley VCH-Verlag CY - Weinheim AN - OPUS4-48720 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Brüske, H. A1 - Thöns, Sebastian T1 - Value of pre‐construction proof loading information for structural design N2 - We introduce a new concept that enables a decision analyst to explore and quantify the benefits of decision alternatives that exceed the scope of a pre‐posterior decision or value of information analysis. This new concept, namely, the expected value of sample information and action analysis, facilitates to examine decision alternatives that become only possible with additional knowledge. The concept is introduced by taking basis in proof load testing as a source of (pre‐)posterior knowledge. Pre‐posterior decision analysis is necessary in order to optimize the structural design through proof loading information. The application of the common value of information Analysis and the new value of information and action analysis are demonstrated in a case study. KW - Value of information and action KW - Pre‐construction proof loading KW - Pre‐posterior decision analysis KW - Structural design optimization PY - 2019 DO - https://doi.org/10.1002/we.2398 SN - 1095-4244 SP - 1 EP - 17 PB - John Wiley & Sons AN - OPUS4-48804 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz T1 - Wellenmessungen zur Identifikation der dynamischen Eigenschaften von Böden N2 - Erschütterungen durch Industrie und Verkehr, Schwingungen von Gebäuden, Fundamenten und Gleisen hängen im hohen Maße vom jeweiligen unterliegenden Boden ab. Die Eigenschaften des Bodens ermitteln wir mit Wellenmessungen vor Ort. Die Wellen werden in der Regel mit einem Impulshammer erzeugt und mit Geophonen als Schwinggeschwindigkeits-signale gemessen. Geophone sind aktive Sensoren, die eine kleine Messspannung liefern. Ein 72-kanaliges Messsystem mit entsprechenden Messverstärkern ist im Messwagen der Arbeitsgruppe eingebaut. Es werden im Vortrag fünf verschiedene Auswertemethoden vorgestellt. Im einfachsten Fall versucht man die Laufzeit von einem Geophon zum andern auszumessen und damit die vorherrschende Wellengeschwindigkeit zu ermitteln. Wir haben Wellengeschwindigkeiten von 30 m/s für Moorboden bis 1000 m/s für Felsboden gemessen. Der Boden hat aber nicht nur eine Wellengeschwindigkeit, sondern mehrere frequenzabhängige Wellen-geschwindigkeiten. Dadurch wird aus einem kurzen Hammerschlag eine längere Schwingung (Zerstreuung, Dispersion). Für die Auswertung von dispersiven Wellen nutzt man die spektrale Analyse, zunächst mit zwei Aufnehmern (SASW Spectral Analysis of Surface Waves), später mit einer ganzen Messachse (Multi-Station SASW). Schließlich kann man eine ganze Messachse auch mit verschiedenen Transformationsmethoden auswerten wie die f,v-Methode und Spatial AutoCorrelation SPAC Methode. Alle diese Methoden wurden von uns auf Messreisen in Deutschland, Österreich und der Schweiz getestet. Durch die Approximation der frequenzabhängigen Wellengeschwindigkeiten erhält man ein passendes Bodenmodell. Zu diesem Bodenmodell kann man die Übertra¬gungsfunktionen für Hammer- und Zuganregung berechnen. Bei etlichen Mess¬orten wurden deutliche Merkmale einer Bodenschichtung beobachtet. Es ergibt sich eine Reduktion der tiefen Frequenzanteile durch den steifen unterliegenden Halbraum. Die weiche Deckschicht bestimmt das hochfrequente Verhalten. T2 - Vortragsseminar der BAM-Abteilung 7 Bauwerkssicherheit CY - Berlin, Germany DA - 27.8.2019 KW - Wellenausbreitung KW - Spektralanalyse KW - Wellengeschwindigkeit PY - 2019 AN - OPUS4-48866 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Bäßler, Ralph T1 - Book review: Conjugated polymers - Perspective, theory, and new materials N2 - In this also completely rewritten and reorganized second part of the two‐volume set 45 international experts comprise the current knowledge of conjugated polymers. In addition to part one on properties, processing characterization and morphology, 16 chapters cover perspectives, theory and new materials. Finally, it can be concluded that this 4th edition of this handbook fulfills, like the first part, its intention, to be the definitive resource on the topic of conducting polymers. This is assured by the updated and added contributions of all authors, which consider the significant developments both in fundamental understanding, progress and applications since publication of the previous edition. So, it can be recommended to everyone, who wants to get a comprehensive overview on conjugated polymers, not just to researchers, advanced students, and industry professionals working in materials science and engineering. KW - Polymer KW - Testing PY - 2019 DO - https://doi.org/10.1002/maco.201970094 SN - 1521-4176 SN - 0947-5117 VL - 70 IS - 9 SP - 1727 PB - WILEY‐VCH Verlag GmbH & Co. KGaA CY - Weinheim AN - OPUS4-48886 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Bäßler, Ralph T1 - Rezension: Wörterbuch der Metallurgie und Metallverarbeitung ‐ Englisch‐Deutsch – Deutsch‐Englisch N2 - Die erste Auflage dieses klassischen Wörterbuches enthält hochspezialisierte Fachbegriffe nicht nur aus dem Bereich der Metallurgie, sondern auch zum Schweißen, Löten und zur Korrosion. Besonderer Wert wurde vom Autor auf einen korrekten Bezug zum jeweiligen Anwendungsgebiet gelegt. Letztendlich erfüllt das Wörterbuch das Ansinnen seines Autors,aus der Vielzahl von Quellen und Anwendungsgebieten die relevanten Begriffe mit dem korrekten Pendant zusammenzustellen und bietet dem Nutzer eine Grundlage für korrekte Begrifflichkeit und Kommunikation im internationalen Kontakt. KW - Metallurgie PY - 2019 DO - https://doi.org/10.1002 maco.201970096 SN - 1521-4176 SN - 0947-5117 VL - 70 IS - 9 SP - 4 EP - 5 PB - WILEY‐VCH Verlag GmbH & Co. KGaA CY - Weinheim AN - OPUS4-48888 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Babutzka, Martin T1 - Investigation of the salinization in marine and offshore environment - test methods and challenges N2 - Salinization and contamination of metal surfaces by chloride-containing aerosols is of great importance with regard to corrosion phenomena in the maritime sector and in offshore applications. Especially Offshore Wind Turbines are exposed to extreme corrosive conditions due to high chloride concentrations in the atmosphere and the resulting high chloride deposition rates. It is of great importance to evaluate to what extent salinization of the surface influences the corrosion protection of coatings and pitting occurrence on stainless steels under atmospheric conditions to evaluate the durability of metallic building structures in offshore and marine environments. The evaluation of the scientific literature and regulatory guidelines has shown that there are still many open questions regarding the contamination of metal surfaces by chlorides. This contribution will discuss how salinization of metal surfaces is evaluated and monitored according to current standards and guidelines. Future challenges concerning test methods and the application of evaluated salinization values and deposition rates will be discussed. T2 - 5th International Conference on Smart Monitoring, Assessment and Rehabilitation of Civil Structures CY - Potsdam, Germany DA - 27.08.20019 KW - Maritime Atmosphäre KW - Versalzung KW - Maritime atmosphere KW - Salinization PY - 2019 SP - Th.2.A.5, 1 EP - 8 PB - SMAR 2019 AN - OPUS4-48905 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Babutzka, Martin T1 - Prüfverfahren zur Bewertung der kathodischen Enthaftung bei organischen Beschichtungen – Eine kritische Betrachtung N2 - Zum Schutz vor Korrosionsprozessen werden metallene Werkstoffe in der Automobilindustrie üblicherweise mit komplexen Beschichtungssystemen versehen. Durch eine Beschädigung des Beschichtungssystems kann bei Zutritt von Feuchtigkeit und korrosionsstimulierenden Ionen das Metallsubstrat korrodieren und unter Umständen die Beschichtung im Bereich neben der Verletzung enthaften. Dabei gibt es verschiedene Mechanismen, die zu einer Unterwanderung und Enthaftung der Beschichtung führen können. In jedem Fall wird aber die Dauerhaftigkeit des Korrosionsschutzes negativ beeinflusst und die Lebensdauer des Bauteils herabgesetzt. Die Industrie versucht deshalb, Beschichtungssysteme zu entwickeln, die dem Vorgang der kathodischen Enthaftung bestmöglich widerstehen können. Einen kritischen Entwicklungs- und Qualifizierungsschritt stellt dabei die geeignete Prüfung auf kathodische Unterwanderung und Enthaftung dar, da eine Prüfung der Beschichtung möglichst schnell und kosteneffizient zu belastbaren Ergebnissen führen soll. Neben den industriell üblichen Salzsprühnebeltests kommen häufig elektrochemische Polarisationstests zur Anwendung. Verschiedene Automobilherstellerhaben verwenden jeweils angepasste Tests, die sich bezüglich der Prüfparameter unterscheiden. Bei allen Testvarianten wird aber versucht, durch Verschärfung der Prüfparameter kurze Prüfzeiträume zu erreichen. Dabei kann es aber dazu kommen, dass die real ablaufenden Mechanismen der Unterwanderung beeinflusst und verändert werden und das Prüfergebnis von Ergebnissen im Feld zum Teil stark abweicht. Im Vortrag werden mit Blick auf die geltenden Regelwerke und Normen die Unterschiede verschiedener Prüfmethoden zur kathodischen Enthaftung bei organischen Beschichtungen vorgestellt und deren Aussagekraft kritisch betrachtet. Am Beispiel von systematischen Versuchsreihen an einem ausgewählten Kurzzeittest werden die Grenzen einiger Methoden herausgearbeitet und die Anwendbarkeit für Qualitätsprüfungen betrachtet. Durch den Ansatz der statistischen Versuchsplanung wird der Einfluss einzelner Prüfparameter auf die Enthaftung und das Ergebnis des Kurzzeittests gezeigt. T2 - ZVO-Oberflächentage CY - Berlin, Germany DA - 11.09.2019 KW - Kathodische Enthaftung KW - Korrosionsprüfung KW - Organische Beschichtungen KW - Cathodic delamination KW - Corrosion testing KW - Organic coatings PY - 2019 AN - OPUS4-48960 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Straub, D. A1 - Schneider, Ronald A1 - Bismut, E. A1 - Kim, H.-J. T1 - Reliability analysis of deteriorating structural systems N2 - Reliability analysis of deteriorating structural systems requires the solution of time-variant reliability problems. In the general case, both the capacity of and the loads on the structure vary with time. This analysis can be approached by approximation through a series of time-invariant reliability problems, which is a potentially effective strategy for cases where direct solutions of the time-variant reliability problem are challenging, e.g. for structural systems with many elements or arbitrary load processes. In this contribution, we thoroughly Review the formulation of the equivalent time-invariant reliability problems and extend this approximation to structures for which inspection and monitoring data is available. Thereafter, we present methods for efficiently evaluating the reliability over time. In particular, we propose the combination of sampling-based methods with a FORM (first-order reliability method) approximation of the series system reliability problem that arises in the computation of the lifetime reliability. The framework and algorithms are demonstrated on a set of numerical examples, which include the computation of the reliability conditional on inspection data. KW - Monitoring KW - Reliability KW - Deterioration KW - Structural systems KW - Bayesian analysis KW - Inspection PY - 2020 DO - https://doi.org/10.1016/j.strusafe.2019.101877 VL - 82 SP - Paper 101877, 1 PB - Elsevier Ltd. AN - OPUS4-48952 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Long, Lijia T1 - On the value of SHM information for offshore wind turbines N2 - Applications of Structural Health Monitoring (SHM) for the design and analysis of Offshore Wind Turbine (OWT) structures has gained much attention within the past few years. Being exposed to repeated cyclic wind and wave loads, OWTs are dynamically sensitive structures and can benefit from monitoring systems to predict time-dependent deterioration. This study focuses on the quantification of the value of SHM information on the maintenance of OWT structures, with emphasis on fatigue of welded joint. By utilizing the decision tree, structural reliability, SHM data, as well as the cost-benefit assessments, a value of information (VoI) analysis can be done to model the fundamental decision of whether the service life of an OWT foundation can be extended beyond the initial design life. The application is demonstrated on a butt weld of a monopile support structure of a 3 MW offshore wind turbine with a hub height of approximately 71m where the prior probability analysis is modelled as a probabilistic fatigue damage model based on S-N approach and designed wind data. The posterior probability of failure of welded joints is updated using the three-year measured oceanographic and one-year strain data. The expected value of SHM information can be found as the difference between the maximum utility obtained in posterior analysis with SHM information and the maximum utility obtained using only prior information. This work can provide insights on how much benefits can be achieved through SHM information, with practical relevance on reliability-based design optimization and fatigue life extension of OWT structures. T2 - INFRASTAR Training School, Nantes CY - Nantes, France DA - 08.04.2019 KW - Offshore wind turbines KW - SHM information KW - Wind turbine operator KW - Strain measurement PY - 2019 AN - OPUS4-48478 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Long, Lijia T1 - Quantification of the value of monitoring information for deteriorated structures N2 - A method to determine the structural and damage detection system influencing parameters is proposed based on the value of information analysis. The value of information analysis utilizes the Bayesian pre-posterior decision theory to quantify the value of SHM for the structural integrity management during service life. First the influencing parameters of the structural system such as deterioration type and rate are introduced for the performance of the prior probabilistic system model. Then the damage detection system performance influencing parameters including number of sensors, sensor locations, measurement noise and the Type I error are investigated. The pre-posterior probabilistic model is computed utilizing the Bayes’ theorem to update the prior system model with the damage indication information. Finally, the value of information is quantified as the difference between the maximum utility obtained in pre-posterior and prior analysis based on the decision tree analysis, comprising structural probabilistic models, consequences as well as benefit and costs analysis associated with and without monitoring. With the developed approach, a case study on a statically determinate Pratt truss bridge girder is carried out to validate the method. The analysis shows that the higher the deterioration rate is, the more it is beneficial to do SHM. Furthermore, it shows that more sensors do not necessarily lead to a higher value of information; only specific sensor locations near the highest utilized components lead to a high value of information; measurement noise and the Type I error should be controlled and as small as possible. An optimal sensor employment with highest value of information is found. Moreover, it is found that the proposed method can be a powerful tool to develop optimal service life maintenance strategies - before implementation - for similar bridges and to optimize the damage detection system settings and sensor configuration for minimum expected costs and risks. T2 - INFRASTAR Training School, Nantes CY - Nantes, France DA - 08.04.2019 KW - Damage detection KW - Value of information KW - Monitoring information PY - 2019 AN - OPUS4-48480 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Long, Lijia A1 - Alcover, I. F. A1 - Thöns, Sebastian T1 - Quantification of the posterior utilities of SHM campaigns on an orthotropic steel bridge deck N2 - This paper contains a quantification and decision theoretical optimization of the posterior utilities for several options for monitoring campaigns on the particular case of fatigue life predictions of an orthotropic steel deck. The monitoring campaigns are defined by varying monitoring durations and phases. The decision analysis is performed with real data from the Structural Health Monitoring (SHM) of the Great Belt Bridge (Denmark) which, among others, consist of measured strains, pavement temperatures and traffic intensities. The fatigue loading prediction model is based on regression models linking daily averaged pavement temperatures, daily aggregated heavy-traffic Counts and derived S-N fatigue damages, all of them derived from the outcomes of different monitoring campaigns. A probabilistic methodology is utilized to calculate the fatigue reliability profiles of selected instrumented welded joints. The posterior utilities of SHM campaigns are then quantified by considering the structural fatigue reliability, various monitoring campaigns and the corresponding cost-benefit models. The decisions of identifying the optimal monitoring campaign and of extending the service life or not in conjunction with monitoring results are modelled. The optimal monitoring campaign is identified - retrospectively - by maximizing the expected benefits and minimize risks in dependency of the monitoring duration and the monitoring associated costs. The results, despite relying on a number of simplistic assumptions, pave the way towards the use of pre-posterior decision support to optimise the design of monitoring campaigns for similar bridges, with an overall goal to proof the cost efficiency of SHM approaches to civil infrastructure management. T2 - IWSHM 2019, The 12th International Workshop on Structural Health Monitoring, Stanford, California, USA CY - Stanford, California, USA DA - 10.09.2019 KW - Quantification KW - SHM information KW - Steel bridge deck PY - 2019 SP - 1 EP - 9 AN - OPUS4-48481 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Long, Lijia A1 - Alcover, I. F. A1 - Thöns, Sebastian T1 - Quantification of the posterior utilities of SHM campaigns on an orthotropic steel bridge deck N2 - This paper contains a quantification and decision theoretical optimization of the posterior utilities for several options for monitoring campaigns on the particular case of fatigue life predictions of an orthotropic steel deck. The monitoring campaigns are defined by varying monitoring durations and phases. The decision analysis is performed with real data from the Structural Health Monitoring (SHM) of the Great Belt Bridge (Denmark) which, among others, consist of measured strains, pavement temperatures and traffic intensities. The fatigue loading prediction model is based on regression models linking daily averaged pavement temperatures, daily aggregated heavy-traffic Counts and derived S-N fatigue damages, all of them derived from the outcomes of different monitoring campaigns. A probabilistic methodology is utilized to calculate the fatigue reliability profiles of selected instrumented welded joints. The posterior utilities of SHM campaigns are then quantified by considering the structural fatigue reliability, various monitoring campaigns and the corresponding cost-benefit models. The decisions of identifying the optimal monitoring campaign and of extending the service life or not in conjunction with monitoring results are modelled. The optimal monitoring campaign is identified - retrospectively - by maximizing the expected benefits and minimize risks in dependency of the monitoring duration and the monitoring associated costs. The results, despite relying on a number of simplistic assumptions, pave the way towards the use of pre-posterior decision support to optimise the design of monitoring campaigns for similar bridges, with an overall goal to proof the cost efficiency of SHM approaches to civil infrastructure management. T2 - The 12th International Workshop on Structural Health Monitoring CY - Stanford University, CA, USA DA - 10.09.2019 KW - SHM KW - Posterior utilities KW - Orthotropic steel bridge deck PY - 2019 SP - 265 EP - 274 AN - OPUS4-49174 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Wagner, Adrian T1 - Innovation und Sicherheit durch den Einsatz von Duplexstählen in Straßentunneln N2 - Ziel des Projektes ist die Qualifizierung von Duplexstählen in Tunnelbauwerken um die Einsatzmöglichkeiten alternativer nichtrostender Stähle zu den bislang gebräuchlichen rostfreien Edelstählen 1.4404 und 1.4571 zu eruieren. Da Duplexstähle im Vergleich zu austenitischen Stählen über eine doppelt so hohe Festigkeit verfügen, können Bauteile schlanker konstruiert werden, wodurch Material eingespart werden kann. Neben der Wirtschaftlichkeit muss die Dauerhaftigkeit untersucht werden. Dazu wurden speziell konzipierte Wand- und Deckenracks mit unterschiedlichen metallenen Werkstoffen und Oberflächen hergestellt und in den Tunnelbauwerken montiert. Nach bestimmten Auslagerungszeiten von bis zu drei Jahren werden die Proben demontiert und auf ihr Korrosionsverhalten untersucht. Ein weiteres Ziel neben der Qualifizierung der Werkstoffgruppe sind die Reduktion der Instandsetzungs- und Wartungsmaßnahmen der Tunnelbetreiber T2 - 3. Tunnelsymposium in Hallein CY - Hallein, Austria DA - 26.09.2019 KW - Duplex KW - Tunnel KW - Korrosion PY - 2019 AN - OPUS4-49165 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Trubiroha, P. A1 - Geburtig, Anja A1 - Wachtendorf, Volker T1 - 40 Years of Global-UV-Test weathering device: with fluorescent UV lamps and a precise microclimatical control into the future N2 - On the basis of a lot of investigation on the spectral sensitivity of photo degradation of plastics and on the underestimated influence of temperature and relative humidity on degradation processes a new type of weathering device was presented at the end of the seventies: It was a combination of a radiation source with fluorescent UV lamps and a precise climatic cabinet. The radiation emission from a combination of four different types of fluorescent UV lamps was superimposed on the specimen surfaces in the climatic cabinet to match the UV part of solar radiation as closely as possible. Air temperature was controlled to within ± 1 °C, and relative humidity to within ± 5 %RH. As the lamps’ emission is focussed on the UV range almost no radiation heating of the sample occurs. Therefore, the temperature of the sample, which is the quantity of consideration for the degradation, is nearly identical with the chamber’s air temperature, which is the quantity to be controlled. Also, therefore, high humidity can be obtained on the sample surface. The limitation of the emission to the UV range is sufficient for the study of the polymer matrix. This type of weathering device offers an exactness of microclimatic control of the sample’s surface, which should be a standard for weathering devices. Even now it is the only weathering device which generates pure relative humidity (without aerosol). T2 - 9th European Weathering Symposium CY - Basel, Switzerland DA - 18.09.2019 KW - Weathering KW - Irradiation PY - 2019 SN - 978-3-9818507-5-8 SP - 37 EP - 47 PB - Thomas Würtz Grafik-Design CY - Karlsruhe, Germany AN - OPUS4-49151 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Wachtendorf, Volker A1 - Geburtig, Anja A1 - Trubiroha, P. T1 - Application of a newly proposed sensor for effective UV-irradiance for the monitoring of both natural and artificial weathering conditions N2 - To improve on the classic radiometric sensor with radiometric measurement [ ] here a new UV-sensor characteristic for effective UV is proposed that no longer applies equal weighting of spectral irradiation into the UV irradiance value but rather aims at approaching a weighting according to a typical spectral sensitivity curve of polymers. This curve resembles the erythema curve of the skin which is the basis of the UV-index. For the use of the sensor it would be desirable to keep it in the artificial weathering device for the complete weathering test (including rain phases) while the same sensor should also be applicable for the monitoring of outdoor weathering exposures. A first application of this kind of weighted measurement and a comparison with radiometric measurements accompanied with polymer ageing results will be presented together with conclusions for a future effective UV irradiance sensor. T2 - 9th European Weathering Symposium CY - Basel, Switzerland DA - 18.09.2019 KW - UV-irradiance PY - 2019 SN - 978-3-9818507-5-8 VL - 19 SP - 293 EP - 306 AN - OPUS4-49154 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Metz, Christian A1 - Franz, Philipp A1 - Fischer, C. A1 - Wachtendorf, Volker A1 - Maierhofer, Christiane T1 - Zerstörungsfreie Charakterisierung der Alterung additiv gefertigter Kunststoffbauteile N2 - Das vorgestellte Projekt beschäftigt sich mit den optischen, thermophysikalischen und mechanischen Materialeigenschaften von additiv gefertigten Kunststoffteilen und deren Alterung. Dazu wurden mittels Fused Layer Modeling (FLM) Probekörper aus ABS hergestellt, die anschließend für drei Monate einer künstlichen Bewitterung unterzogen wurden. Die dabei erzeugte definierte Alterung wurde nach drei Zeitabschnitten jeweils mit zerstörungsfreien Methoden charakterisiert. Dabei wurde neben den spektroskopischen Standardmethoden auch die aktive Thermografie eingesetzt. Die Ergebnisse zeigen, dass sich mittels der Thermografie sowohl chemische Veränderungen als auch mechanische Schädigungen (Fehlstellen) darstellen lassen. Die Bewitterung beeinflusst die Teiltransparenz der Proben zumindest im sichtbaren Spektralbereich, was bei der Charakterisierung der Fehlstellen, die mittels optisch angeregter aktiver Thermografie detektiert wurden, berücksichtigt werden muss. T2 - DGZfP-Jahrestagung 2019 CY - Friedrichshafen, Germany DA - 27.05.2019 KW - 3D Druck KW - Additive Fertigung KW - Thermografie KW - Polymere KW - Künstliche Bewitterung PY - 2019 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-491561 UR - https://jt2019.dgzfp.de/Portals/jt2019/bb/Di.3.B.1.pdf SN - 978-3-947971-02-2 VL - 171 SP - 1 EP - 8 PB - Deutsche Gesellschaft für Zerstörungsfreie Prüfung (DGZfP) CY - Berlin AN - OPUS4-49156 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schartel, Bernhard T1 - Flame Retardant Polyurethane: An Old, an Actual, and a Future Challenge N2 - This paper is based mainly on the results of two different projects performed in the group of the author recently (2016-2019). The three external partners involved in these two projects are competent in the preparation of FPUF (ICL IP America), RPUF (Department of Industrial Engineering, Padova University), and TPU (Fraunhofer-Institut für Betriebsfestigkeit und Systemzuverlässigkeit LBF, Darmstadt) as well as for the specimen preparation. Systematically varied sets of materials were prepared as the key basic for scientific discussion, varying the kind and combination of flame retardant, PUR structure, density, and blowing agent. A multimethodical approach based on thermogravimetry (TGA), TGA coupled with evolved gas analysis (TGA-FTIR) and pyrolysis GC-MS was used for investigating the pyrolysis. The flammability was addressed using oxygen index (OI) and testing in UL 94 burning chamber in vertical and horizontal set-up. The fire behaviour was addressed by using a cone calorimeter. Beyond these methods according to the state of the art, key experiments were performed. We addressed the dripping and the two-stage burning of TPU using a self-designed apparatus and specific data evaluation, the foam burning through quenching burning samples, using different special sample holders, and measuring temperature profiles within the burning foams. The investigation is made round by intensive analysis of the fire residues, such as comprehensive investigation of the morphology. Result on the pyrolysis (TGA-FTIR, Pyrolysis-GC/MS), flammability (UL 94, LOI), and fire behaviour (cone calorimeter) of TPU and flame retardant TPUs are shown. We discuss in detail the characteristic of PUR decomposition: the low tendency to char, and the specific two step decomposition and how these characteristics control the regimes in fire behaviour. We demonstrate that the different burning regimes are controlled by different pyrolysis products and effective heat of combustions. The resulting formation of pool fires as well as the formation of dripping is discussed in detail. The latter quite important to understand the flame retardancy applied with respect to achieve the UL 94 classification V0 nondripping or V0 non-flaming dripping. Rigid and flexible PUR foams and their flame retarded versions are investigated for different densities. Water and pentane-blown foams are compared as well as PUR and polyisocyanurate-polyurethane (PIR) foams. Horizontal testing in the cone calorimeter is used and the vertical foam specimen holder as well. Self-designed set-ups within the cone calorimeter enable a better inside in the pyrolysis front running through the foam samples as well as the development of the temperature gradient inside the foam during the fire test. The morphology change during burning was characterised by the means of quenching burning foams with liquid nitrogen and investigating the cross sections with scanning electron microscope. In sum, a rather comprehensive study was performed to work out the principle fire phenomena controlling the fire behaviour of PUR foams in a very systematic and significant way. Promising flame retardancy approaches are discussed. The importance of either combining the drain of fuel and flame inhibition or charring into an effective protection layer/multicellular structure is underlined. This contribution focusses the general conclusions and trends. It tries to increase the understanding of the specific and demanding challenge to develop flame retardant PUR materials. T2 - Interflam 2019, 15th International Interflam Conference CY - Egham, UK DA - 01.07.2019 KW - Polyurethane KW - Flame retardant KW - Dripping KW - Flammability KW - Pool fire KW - Pyrolysis KW - Decomposition KW - Foams PY - 2019 AN - OPUS4-48557 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Lenz, J. A1 - Pospiech, D. A1 - Paven, M. A1 - Albach, R. W. A1 - Günther, Martin A1 - Schartel, Bernhard A1 - Voit, B. T1 - Improving the Flame Retardance of Polyisocyanurate Foams by Dibenzo[d,f][1,3,2]dioxaphosphepine 6-Oxide-Containing Additives N2 - A series of new flame retardants (FR) based on dibenzo[d,f][1,3,2]dioxaphosphepine 6-oxide (BPPO) incorporating acrylates and benzoquinone were developed previously. In this study, we examine the fire behavior of the new flame retardants in polyisocyanurate (PIR) foams. The foam characteristics, thermal decomposition, and fire behavior are investigated. The fire properties of the foams containing BPPO-based derivatives were found to depend on the chemical structure of the substituents. We also compare our results to state-of-the-art non-halogenated FR such as triphenylphosphate and chemically similar phosphinate, i.e. 9,10-dihydro-9-oxa-10- phosphaphenanthrene-10-oxide (DOPO), based derivatives to discuss the role of the phosphorus oxidation state. KW - Polyisocyanurate KW - Dibenzo[d,f][1,3,2]dioxaphosphepine 6-oxide KW - Phospha-Michael addition KW - Flame retardant KW - Foams PY - 2019 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-485590 DO - https://doi.org/10.3390/polym11081242 SN - 2073-4360 VL - 11 IS - 8 SP - Article 1242 PB - MDPI AN - OPUS4-48559 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz ED - Ruspighi, Emiliano T1 - Vehicle-track-soil interaction and train-induced ground vibration: Theory and measurements in Germany, Switzerland and France N2 - Abstract. Three measurement campaigns of train-induced ground vibrations are evaluated for the vehicle-track-soil interaction. Ground vibrations, track vibrations and vehicle vibrations have been measured for train passages and impulse excitation and compared with theoretical results. The soil and the track-soil system are calculated by wavenumber integrals. The influence of the vehicle is introduced by a substructure method. By comparing theory and measurement the different components of excitation force and ground vibration can be analysed, the quasi-static excitation, track-alignment errors, the out-of-roundness of wheels, the wheel and rail roughness, and moreover, scattered axle impulses and ineffective high-frequency parts of the wheelset accelerations and forces. T2 - 13th International Conference on recent Advances in Structural Dynamics CY - Lyon, France DA - 15.4.2019 KW - Vehicle-track interaction KW - Train-induced ground vibration KW - Ground vibration measurements PY - 2019 SP - 810 EP - 821 PB - University of Southampton CY - Southampton AN - OPUS4-48423 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schartel, Bernhard T1 - Understanding flame retardant modes of action: a wellspring for evidence-based development N2 - Although the main flame retardant modes of action are known, in practise the detailed scientific understanding usually falls short, when it comes to modern multicomponent systems, the important tiny optimizations, or quantifying in terms of specific fire properties. The description of the flame retardant modes of action remains usually vague and fragmentary. This talk tries to deliver thought-provoking impulses how the understanding of the fire behaviour and flame retardancy can be utilized to direct the development of future flame retardant polymer products. Some overseen details are picked up as well as rethinking of concepts memorised long ago is encouraged to discover something new. Furthermore, the talk tries to fill the gap between flame retardant modes of action and fire performance constituting a product. This talk promotes the evidence-based development of flame retardant polymers T2 - FRPM 2019, 17th European Meeting on Fire Retardant Polymeric Materials CY - Turku, Finland DA - 26.06.2019 KW - Flame retardant KW - Modes of action KW - Fire behaviour PY - 2019 AN - OPUS4-48551 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Lenz, J. T1 - Novel phosphonates as flame retardants for polymers N2 - As a potential substitute for currently used halogenated flame retardants we explored the synthesis of dibenzo[d,f][1,3,2]dioxaphosphepine 6-oxide (BPPO) and derivatives. BPPO is a cyclic phosphonate and was synthesized by a simple, three-component condensation using 2,2´-biphenol, phosphorus trichloride and water by improving a procedure given by Natchev. Subsequently, BPPO was employed in phospha-Michael additions in line with the known synthesis of DOPO-compounds to double bonds. These reactions result in novel phosphorus-containing compounds with flame retardant activíty. The chemical structure of the unsaturated compounds was systematically varied yielding non-reactive flame retardants (without functional groups) from acrylates and diesters, and reactive (with functional groups) flame retardants from p-benzoquinone. The use of the phosphonate BPPO and its derivatives as flame retarding additives has not been described yet. The BPPO ring is highly reactive. Therefore, it is supposed that it mainly acts in the gas phase. The new phosphonates were applied as additives for improving the flame retardancy of rigid PUR/PIR foams with triethyl phosphate (TEP) as plasticizer. The foam characteristics like density, cell integrity, pore size and mechanical properties were investigated. The burning properties of the foams were analyzed in the vertical flame spread according to DIN 4102 and by cone calorimetry. The relevant parameters depended on the phosphorus content, which is illustrated for PIR foams with ethyl 3-(6-oxidodibenzo[d,f][1,3,2]dioxaphosphepin-6-yl)propanoate (X, Z = H; Y = OEt; EA-BPPO) as FR additive. At comparable P-content, the EA-BPPO additive reached the PHHR-values of the benchmark foam with TEP and triphenyl phosphate as FR additive. With increased P-content the values were further reduced. TML and MARHE parameters showed a similar tendency. The FR additives dispersed well in the formulation and had no significant influence on foam density, cell integrity and pore size compared to the reference sample. T2 - FRPM 2019, 17th European Meeting on Fire Retardant Polymeric Materials CY - Turku, Finland DA - 26.06.2019 KW - Phosphonate KW - Flame retardant KW - PUR foams PY - 2019 AN - OPUS4-48554 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Tabaka, Weronika T1 - Bench-scale fire stability testing – The most effective method to investigate structural integrity of Carbon Fiber Reinforced Polymer Composites N2 - Fire resistance testing of components made of carbon fibre reinforced polymers (CFRP) composites usually demands intermediate-scale or full-scale testing. In this study a bench-scale test is presented as practicable and efficient method to assess the improvement in structural integrity of CFRP with different protective coatings during fire. T2 - FRPM 2019, 17th European Meeting on Fire Retardant Polymeric Materials CY - Turku, Finland DA - 26.06.2019 KW - Composite in Fire KW - Fire Stability KW - Bench-scale Fire Testing KW - Intumescencent Coatings KW - Nanopaper PY - 2019 AN - OPUS4-48555 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Pospiech, D. T1 - Decomposition and combustion behavior of lignin-containing polyesters: development of new carbon fiber precursors and flame retarded polyester fibers N2 - Our approach includes the preparation of blends of preferably liquid-crystalline polyesters with Lignin, but also the synthesis of new polyesters with Lignin-related monomer units. While most studies employ pulped Lignin directly, we first purified the Kraft Lignin by fractionation, followed by chemical modification of the terminal OH groups. Acetylation results in the reduction of glass transition temperatures (Tg) below 200°C, improved processability in the melt with complete melting of the Lignin sample, and higher thermostability. These Lignin fractions were melt-mixed in a mini-twin-screw extruder with polyesters. The chemical structure of the polyesters was systematically varied between poly(ethylene terephthalate), (PET); poly(ethylene terephthalate-co-oxybenzoate), (PET/HBA); liquid crystalline polyesters with fully aromatic structure; and polyesters with Lignin-related monomers like ferulic and vanillic acid). The polymer influence on the blending behavior with Lignin was examined. SEM revealed phase-separated blends with partial compatibilization of the phases indicated by the shift of Tg’s. The influence of the polyester and the Lignin on decomposition and combustion was accessed by thermogravimetry (TGA), TGA-FTIR and pyrolysis-combustion flow calorimetry (PCFC) and compared to the decomposition of polyesters. The main focus was to achieve melt-spinnable blends for fibres with improved flame retardancy or as precursors for carbon fibers. Blends of Lignin fractions with the aromatic-aliphatic polyesters (here preferably PET/HBA) were successfully spun into fibers with lab-scale melt-spinning equipment. X-ray measurements revealed orientation of the fibers with Lignin. The E-moduli raised with increasing purity of the Lignin fractions (e.g., by removal of reducing sugars). The structure of the polymer matrix determines the decomposition and combustion behavior of the blends with Lignin. Incorporation of aliphatic subunits reduces the amount of remaining char formed in TGA and PCFC from about 40-45 wt% for fully aromatic polyesters to 18-25 wt% for semiaromatic polyesters (at almost comparable carbon content in the polymer), while the maximum temperature of combustion decreased from 480-530°C for the former to 410-465°C for the latter. Lignin fractionation and acetylation yields samples with high char content (36 wt%) and extremely low heat release capacity (80-90 kJ/gK) with combustion maximum temperature at 405°C. Lignin/ PET/HBA blends combine the low HRC with intermediate char and offer interesting opportunities for polyester fibers with improved flame retardancy without adding P-containing FRs. The flame retardancy behavior was explored by limiting oxygen index measurements on injection-molded parts and fibers. T2 - FRPM 2019, 17th European Meeting on Fire Retardant Polymeric Materials CY - Turku, Finland DA - 26.06.2019 KW - Lignin KW - Polyesther KW - Flame retardant PY - 2019 AN - OPUS4-48556 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Auersch, Lutz T1 - Vehicle-track-soil interaction and train-induced ground vibration – Theory and measurements in Germany, Switzerland and France N2 - Three measurement campaigns of train-induced ground vibrations are evaluated for the vehicle-track-soil interaction. Ground vibrations, track vibrations and vehicle vibrations have been measured for train passages and impulse excitation and compared with theoretical results. The soil and the track-soil system are calculated by wavenumber integrals. The influence of the vehicle is introduced by a substructure method. By comparing theory and measurement the different components of excitation force and ground vibration can be analysed, the quasi-static excitation, track-alignment errors, the out-of-roundness of wheels, the wheel and rail roughness, and moreover, scattered axle impulses and ineffective high-frequency parts of the wheelset accelerations and forces. KW - Vehicle-track-soil interaction KW - Train-induced ground vibration KW - Measurement campaigns KW - Wavenumber integrals KW - Components of excitation KW - Wheelset accelerations PY - 2019 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-486702 DO - https://doi.org/10.1088/1742-6596/1264/1/012034 SN - 1742-6596 SN - 1742-6588 VL - 1264 SP - Artikel 012034-1 EP - 12 PB - IOP Publishing Ltd AN - OPUS4-48670 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Chaves Spoglianti de Souza, Roberto A1 - Andreini, M. A1 - La Mendola, S. A1 - Zehfuß, J. A1 - Knaust, Christian T1 - Probabilistic thermo-mechanical finite element analysis for the fire resistance of reinforced concrete structures N2 - This paper presents a probabilistic methodology based on the thermo-mechanical finite elements analysis to investigate the impact of the variability of the thermal properties of the concrete in the fire safety of structures. This is meant to evaluate if characteristic values or safety factors for the conductivity and specific heat are required during the semi-probabilistic structural fire safety assessment. To illustrate the use of the proposed methodology, this work includes a case-study with a tunnel lining which considers the uncertainties related to the thermal and mechanical properties of the concrete, the soil load, and the temperatures described by the standard temperature-time curve. Two failure criteria are considered: one was the maximum temperature of 300 °C at the reinforcement and the other based on the temperature-dependent strength as provided in the Eurocode EN 1992-1-2. Several finite element analyses are performed. The design of experiments is executed by a Correlation Latin Hypercube Sampling. The calculated probability of failure has different values depending on the adopted failure criteria. A sensitivity analysis using the Spearman's rank correlation coefficient was carried out and demonstrates that the uncertainty related to the specific heat has the greatest impact on the results. KW - Thermo-mechanical PY - 2019 DO - https://doi.org/10.1016/j.firesaf.2018.12.005 SN - 0379-7112 SN - 1873-7226 VL - 104 SP - 22 EP - 33 PB - Elsevier AN - OPUS4-48583 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Häßler, Mai A1 - Häßler, Dustin A1 - Hothan, Sascha A1 - Krüger, Simone T1 - Fire tests of steel tension rod systems with intumescent coating N2 - Purpose – The purpose of this paper is to investigate the performance of intumescent coating on tension rod systems and their components. Steel tension rod systems consist of tension rods, fork end connectors and associated intersection or gusset plates. In case of fire, beside the tension rods themselves, the connection parts require appropriate fire protection. Intumescent fire protection coatings prevent a rapid heating of the steel and help secure the structural load-carrying capacity. Because the connection components of tension rod systems feature surface curvature and a complex geometry, high demand is placed on the intumescence and thermal protection performance of the coatings. Design/methodology/approach – In this paper, experimental studies were carried out for steel tension rod systems with intumescent coating. The examined aspects include the foaming and cracking behaviour, the influence of different dry film thicknesses, the heating rate of the steel connecting parts in comparison to the tension rods, and the mounting orientation of the tension rods together with their fork end connectors. Findings – The results show that a decrease in surface curvature and/or an increase inmass concentration of the steel components leads to a lower heating rate of the steel. Moreover, the performance of the intumescent coating on tension rod systems is influenced by themounting orientation of the steel components. Originality/value – The findings based on fire tests contribute to a better understanding of the intumescent coating performance on connection components of tension rod systems. This subject has not been extensively studied yet. KW - Steel KW - Fire test KW - Intumescent coating KW - Reactive fire protection system KW - Tension rod system PY - 2019 DO - https://doi.org/10.1108/JSFE-01-2019-0005 SN - 2040-2317 VL - 11 IS - 1 SP - 22 EP - 32 PB - Emerald Publishing Limited AN - OPUS4-48714 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Le, Quynh Hoa A1 - Bäßler, Ralph A1 - Schiller, B.N. A1 - Beck, M. A1 - Bettge, Dirk T1 - On the corrosion behaviour of co 2 injection pipe steels: role of cement N2 - Carbon Capture and Storage (CCS) is identified as an excellent technology to reach the target of CO2 reduction. However, the safety issue and cost-effectiveness hinder the future of CCS. For the reliability and safety issues of injection wells, the corrosion resistance of the materials used needs to be determined. In this study, representative low-cost materials including carbon steel 1.8977 and low alloyed steel 1.7225 were investigated in simulated pore water at 333 K and under CO2 saturation condition to represent the worst-case scenario: CO2 diffusion and aquifer fluid penetration. These simulated pore waters were made from relevant cement powder to mimic the realistic casing-cement interface. Electrochemical studies were carried out using the pore water made of cement powder dissolved in water in comparison with those dissolved in synthetic aquifer fluid, to reveal the effect of cement as well as formation water on the steel performance. Two commercially available types of cement were investigated: Dyckerhoff Variodur® and Wollastonite. Variodur® is a cement containing high performance binder with ultra-fine blast furnace slag which can be used to produce high acid resistance concrete. On the other hand, Wollastonite is an emerging natural material mainly made of CaSiO3 which can be hardened by converting to CaCO3 during CO2 injection. The results showed the pH-reducing effect of CO2 on the simulated pore water/aquifer (from more than 10 to less than 5) leading to the active corrosion process that happened on both 1.8977 and 1.7225. Electrochemical characterization showed negative free corrosion potential and polarisation curves without passive behaviors. The tested coupons suffered from pitting corrosion, which was confirmed by surface analysis. Interestingly, basing on the pit depth measurements from the tested coupons and the hardness of cement powder, it is suggested that Variodur® performed better than Wollastonite in both aspects. The electrochemical data was compared to that resulted from exposure tests to give a recommendation on material selection for bore-hole construction. T2 - EUROCORR 2019 CY - Sevilla, Spain DA - 09.09.2019 KW - Cement KW - Carbon capture KW - Corrosion and storage (CCUS) technology KW - Utilization KW - Carbon steel KW - Crevice corrosion PY - 2019 SP - Paper 200597, 1 EP - 4 PB - SOCIEMAT CY - Madrid, Spain AN - OPUS4-49109 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Aristia, Gabriela A1 - Le, Quynh Hoa A1 - Bäßler, Ralph T1 - Effect of CO2 gas on carbon steel corrosion in an acidic-saline based geothermal fluid N2 - Geothermal energy is one of the most promising energy resources to replace fossil fuel. To extract this energy, hot fluids of various salts and gases are pumped up from a geothermal well having a certain depth and location. Geothermal wells in volcanic regions often contain highly corrosive CO2 and H2S gases that can be corrosive to the geothermal power-plants, which are commonly constructed of different steels, such as carbon steel. This research focuses on the corrosion behaviour of carbon steel exposed to an artificial geothermal fluid containing CO2 gas, using an artificial acidic-saline geothermal brine as found in Sibayak, Indonesia. This medium has a pH of 4 and a chloride content of 1,500 mg/L. Exposure tests were conducted for seven days at 70 °C and 150 °C to simulate the operating temperatures for low and medium enthalpy geothermal sources. Surface morphology and cross-section of the specimens from the above experiments were analysed using scanning electron microscope (SEM) and energy dispersive X-ray (EDX). Electrochemical tests via open circuit potential (OCP) and electrochemical impedance spectroscopy (EIS) were performed to understand the corrosion processes of carbon steel in CO2-containing solution both at 70 °C and 150 °C. Localized corrosion was observed to a greater extent at 70 °C due to the less protectiveness of corrosion product layer compared to that at 150 °C, where FeCO3 has a high corrosion resistance. However, a longer exposure test for 28 days revealed the occurrence of localized corrosion with deeper pits compared to the seven-day exposed carbon steel. In addition, corrosion product transformation was observed after 28 days, indicating that more Ca2+ cations incorporate into the FeCO3 structure. T2 - EUROCORR 2019 CY - Sevilla, Spain DA - 09.09.2019 KW - Carbon steel KW - CO2 KW - EIS KW - Geothermal KW - Corrosion PY - 2019 SP - Paper 200245, 1 EP - 5 CY - Madrid, Spain AN - OPUS4-49099 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schartel, Bernhard T1 - Weathering resistance of halogen-free flame retardancy N2 - Whereas the degradation of flame retardant polymers has been discussed since decades, only more recently, the lifetime of the flame retardancy itself becomes an important factor, e.g. for cables used as building products. In this work, several kinds of accelerated artificial ageing tests are performed simulating different environmental exposures and thus highlighting different degradation mechanisms: artificial accelerated weathering, climatic chamber, water immersion, salt spray chamber, and autoclave test. The durability is expected to be different for different flame-retardant materials. Thus, various sets of halogen-free fire-retarded polymers were investigated: ethylene vinyl acetate (EVA) with aluminum hydroxide (ATH), boehmite and synergists, ester-based and ether-based thermoplastic polyurethane (TPU) with melamine cyanurate (MC), aluminum diethylphosphinate (AlPi), and boehmite, and glass fiber reinforced polyamide 66 (PA66) with AlPi-based mixtures. Intensive degradation of the surface was observed, e.g. yielding discoloration and yellowing, EVA showed cracking when weathered. Changes in chemical structure was investigated by ATR-FTIR. The flammability was investigated with the cone calorimeter, UL-94 classification, and oxygen index (LOI). The flame retardancy of most of the materials studied degraded only slightly for the investigated exposure times. EVA/ATH achieved an improved LOI due to flame retardants agglomeration at the surface. Sets of materials, based on EVA and TPU, were also investigated as cable jackets. While flame retarded EVA exhibited no dripping during burning, TPU flame-retarded with MC cables showed pronounced melt-dripping. Cone calorimeter tests were carried out using cable rafts as well as our self-made cable module test, simulating a vertical bundle of cables at the bench scale. The comparison of different fire tests, different exposure conditions, and different materials carved out the specific degradation phenomena with respect to each of these parameters. Most of this work was supported by the IGF Project (18926 N) of the Fördergemeinschaft für das Süddeutsche Kunststoff-Zentrum e.V., supported by the AiF within the framework of the program “Förderung der Industriellen Gemeinschaftsforschung (IGF)” of the German Federal Ministry for Economic Affairs and Energy based on a decision of the Deutschen Bundestag. T2 - 33rd Polymer Degradation Discussion Group Conference (PDDG-2019) CY - St. Julian, Malta DA - 01.09.2019 KW - Weathering resistance KW - Durability KW - Flame retardancy PY - 2019 AN - OPUS4-49020 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Eberwein, Robert T1 - Untersuchung der Gefährdung von Personen und Bauwerken in Folge des Versagens von LNG Kraftstoffspeichern für Fahrzeuge in Tunneln N2 - Basierend auf Methan aus regenerativen Quellen, stellt LNG einen alternativen Kraftstoff für den schweren Fernverkehr da. Gegenüber seinen positiven Eigenschaften birgt der Kraftstoff aber auch Risiken, durch seine sehr niedrige Temperatur und seine Brennbarkeit, für die Personen- und Bauwerkssicherheit. Für die Erforschung der Risiken eignen sich CFD-Modelle, deren Erforschung unter anderem Ziel des TF-SiVi Projekts der BAM war. Einen Einblick in die angewendete Methodik zur Erforschung von Unfallszenarien mit LNG gibt der Vortrag. T2 - Kolloquium EVUR CY - TU-Berlin, Germany DA - 17.07.2019 KW - LNG KW - Tunnel KW - Explosion KW - Stoffausbreitung PY - 2019 AN - OPUS4-48494 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Said, Samir A1 - Auersch, Lutz T1 - Measurement of slab track behaviour at different sites N2 - Measured train passages and hammer impacts in combination with track-soil calculation have been successfully used for the detection of damaged slab tracks. This approach is now extended to intact slab and ballast tracks. The vibrations of many tracks have been measured at several levels from rail, sleeper, track plate, base plate, base layer to the subsoil by velocity or acceleration sensors. The time histories have to be integrated once or twice to get the displacements. The displacement signals include an arbitrary time-dependent shift which must be eliminated or respected in the interpretation. On the other hand, the calculation of slab and ballast tracks have been done in frequency-wavenumber domain. The displacements along the track and the frequency-dependent compliance transfer functions can be calculated. The latter can be compared with the results of the hammer impacts on the track. The deformation of the track can be transformed to time histories for a whole train and compared to the measured train passages. Many slab (and ballast) tracks have been measured at different sites. The displacements of the tracks are presented, and the following parameters have been analysed in the measurement results: slab track vs. ballast track, different types of slab tracks, damaged slab tracks, different trains, switches at different measuring points, an elastic layer, the mortar layer, different soils at different places. The soil should have the dominant influence on the track-plate displacements. Slab and ballast track yield also big differences in maximum displacement and width of deformation. Some of the preceding aspects will be analysed in comparison of measurement and theory. T2 - 26th International Congress on Sound and Vibration (ICSV26) CY - Montreal, Canada DA - 07.07.2019 KW - Displacements KW - Train passage KW - Slab track KW - Hammer impact KW - Vibration measurements PY - 2019 AN - OPUS4-48495 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz A1 - Said, Samir T1 - Measurement of slab track behaviour at different sites N2 - Measured train passages and hammer impacts in combination with track-soil calculation have been successfully used for the detection of damaged slab tracks. This approach is now extended to intact slab and ballast tracks. The vibrations of many tracks have been measured at several levels from rail, sleeper, track plate, base plate, base layer to the subsoil by velocity or acceleration sensors. The time histories have to be integrated once or twice to get the displacements. The displacement signals include an arbitrary time-dependent shift which must be eliminated or respected in the interpretation. On the other hand, the calculation of slab and ballast tracks have been done in frequency-wavenumber domain. The displacements along the track and the frequency-dependent compliance transfer functions can be calculated. The latter can be compared with the results of the hammer impacts on the track. The deformation of the track can be transformed to time histories for a whole train and compared to the measured train passages. Many slab (and ballast) tracks have been measured at different sites. The displacements of the tracks are presented, and the following parameters have been analysed in the measurement results: slab track vs. ballast track, different types of slab tracks, damaged slab tracks, different trains, switches at different measuring points, an elastic layer, the mortar layer, different soils at different places. The soil should have the dominant influence on the track-plate displacements. Slab and ballast track yield also big differences in maximum displacement and width of deformation. Some of the preceding aspects will be analysed in comparison of measurement and theory. T2 - 26th International Congress on Sound and Vibration (ICSV26) CY - Montreal, Canada DA - 07.07.2019 KW - Displacements KW - Slab track KW - Train passage KW - Hammer impact KW - Vibration measurements PY - 2019 SN - 978-1-9991810-0-0 SN - 2329-3675 SP - T15RS01_316_1 EP - T15RS01_316_8 PB - Canadian Acoustical Association CY - Montreal, Kanad AN - OPUS4-48498 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Voigt, Sascha A1 - Sträubig, Felix A1 - Palis, Stephan A1 - Kwade, A. A1 - Knaust, Christian T1 - Experimental comparison of Oxygen Consumption Calorimetry and Sensible Enthalpy Rise Approach for determining the heat release rate of large-scale lithium-ion battery fires N2 - From a fire safety point of view, the burning behavior of lithium-ion batteries is of high interest. The heat release rate (HRR) is the most important fire parameter to analyze the fire hazards of burning objects, so that an accurate determination of it is crucial. In this paper, two different measurement techniques, the Oxygen Consumption Calorimetry (OCC) and the Sensible Enthalpy Rise Approach (SERA) are simultaneously performed in the same calorimeter to measure the HRR of two different types of lithium-ion batteries. HRR values as well as total energies determined by SERA are higher than measured with OCC: The total energy released is about 10–12 times (SERA) and 6–9.5 times (OCC) the electrical stored energy for both battery types, whereas the timescales of the release differ strongly between the types, resulting in maximum HRRs of 3.4 MW (SERA) and 1.5 MW (OCC) for one module of type A and 0.8 MW (SERA) and 0.6 (OCC) of type B respectively. Furthermore, a sensitive dependency of the HRR measurement with SERA on the position of the wall temperature measurement is observed. KW - Fire tests KW - Lithium-ion-batteries KW - Heat release rate KW - Calorimetry KW - Sensible enthalpy rise approach KW - Oxygen consumption calorimetry PY - 2021 DO - https://doi.org/10.1016/j.firesaf.2021.103447 SN - 0379-7112 IS - 126 PB - Elsevier Ltd. AN - OPUS4-53441 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Johann, Sergej A1 - Baensch, Franziska A1 - Strurm, Patrick A1 - Tiebe, Carlo A1 - Pötschke, Samuel A1 - Lay, Vera ED - Hall, H. T1 - HF RFID-based Measurement Comparison for Method Optimization in M2 Concrete and Alkali-Activated Mortars N2 - The internal project "SealWasteSafe" of the Federal Institute for Materials Research and Testing is dedicated to the further improvement in the construction of sealing systems for underground repositories of radioactive waste. Particularly, a multi-sensory concept is developed to ensure quality assurance and continuous long-term monitoring on the engineered barriers. Therefore, beside other measures, the temperature and equilibrium moisture of the construction shall be monitored and respective multi-sensoric monitoring concepts are tested first on the laboratory scale. One focus in this project is on embedded application in alkali-activated mortars (AAM), which results in special requirements for the resistance of the sensors to strongly alkaline environments with up to pH 14. In addition, the ingress of water along cables or at sensor positions is critical for sensors embedded in concrete, as the cable access of the sensor housing is a major weak point. It is therefore advisable to equip wireless high frequent radio frequency identification-based sensors, so called HF RFID sensors (short: RFID), that do not require cable access and thus have a stable and leak-proof sensor housing for long-term monitoring. In this contribution, the results from temperature, moisture and transmitted power monitoring of a AAM and a M2 specimens by means of HF RFID sensor systems are presented. T2 - 35th Danubia - Adria Symposium on Advances in Experimental Mechanics CY - Linz, Österreich DA - 21.09.2021 KW - Passive sensor interface KW - RFID KW - Structural Health Monitoring KW - Alkali-Activated Mortars PY - 2021 SN - 978-3-9504997-0-4 SP - 116 EP - 117 AN - OPUS4-53397 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bäßler, Ralph A1 - Yevtushenko, Oleksandra A1 - Le, Quynh Hoa A1 - Bettge, Dirk T1 - Suitability of Metallic Materials in CC(U)S Applications N2 - Carbon Capture Utilization and Storage (CCUS) is a promising technology to reach the target for reduction of CO2 emissions, e.g. from fossil-fuel operated power plants or cement mills. Crucial points for a sustainable and future-proof CCUS procedure are reliability and cost efficiency of the whole process chain, including separation of CO2 from the source, compression of CO2, its subsequent transportation to the injection site and injection into geological formations, e.g. aquifers. Most components that are in contact with CO2-stream consist of steel. Depending on the operating conditions (e.g. temperature, pressure, and CO2-stream composition) specific suitable steels should be used. The compressed CO2-stream is likely to contain process specific impurities; small amounts of SO2 and NO2 in combination with oxygen and water are most harmful. One approach, as currently preferred by pipeline operators, is to clean the CO2-stream to such levels, acceptable for carbon steel, commonly used as pipeline material. Another consideration would be, to use more corrosion resistant alloys for CO2-streams with higher amounts of impurities. Due to the absence of certified benchmarks for upper limits, systematic experiments with impurities in the CO2-stream were carried out reflecting mainly transport and injection conditions. Within the COORAL project (German acronym for “CO2 purity for capture and storage”) levels of impurities in the CO2-stream, being acceptable when using specific steels, were evaluated. Material exposure to dense or multiphase carbon dioxide (CO2) containing specific amounts of water vapor, oxygen (O2) sulfur dioxide (SO2), nitrogen dioxide (NO2), carbon monoxide (CO) can be a challenge to steels. In some situations, condensation of impurities and reaction products from the CO2 stream can occur. CO2 saturated brine is supposed to rise in the well when the injection process is interrupted. The material selection shall ensure that neither CO2 nor brine or a combination of both will leak out of the inner tubing. This COORAL-work was extended by a follow-up project, called CLUSTER. Here the additional influence of impurities was investigated when merging CO2 streams from different sources, combined within a “so-called” cluster. Results are summarized within the following table regarding suitability for different parts of the process chain. T2 - EUROCORR 2021 CY - Online meeting DA - 20.09.2021 KW - Carbon capture storage KW - Corrosion KW - Steel KW - CCS KW - CCU KW - CO2 PY - 2021 SP - 1 EP - 2 AN - OPUS4-53460 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bäßler, Ralph T1 - Suitability of Metallic Materials in CC(U)S Applications N2 - Commercially available carbon steels are suitable for compression and pipelines as long as moisture content and impurities are limited. (water 50 to 100 ppmv, SO2 and NO2 ca. 100 ppmv). Corrosion rates increase with increasing water content. (0.2 – 20 mm/a). Condensation of acids and therefore droplet formation is always possible, even at low water contents. A low SO2 content within the CO2-stream might be more important than a low water content. Cr13-steels showed a general susceptibility to shallow pitting and pitting. So, they seem to be not suitable for CCUS applications. Low alloyed steels showed better corrosion behavior. � (predictable uniform corrosion) For direct contact with saline aquifer fluids only high alloyed steels shall be used. T2 - EUROCORR 2021 CY - Budapest, Hungary DA - 20.09.2021 KW - Carbon capture storage KW - Corrosion KW - Steel KW - CCS KW - CCU KW - CO2 PY - 2021 AN - OPUS4-53461 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Zhou, F. A1 - Ma, C. A1 - Zhang, K. A1 - Chan, Yin Yam A1 - Xiao, Y. A1 - Schartel, Bernhard A1 - Döring, M. A1 - Wang, B. A1 - Hu, W. A1 - Hu, Y. T1 - Synthesis of Ethyl (Diethoxymethyl)phosphinate Derivatives and Their Flame Retardancy in Flexible Polyurethane Foam: Structure-flame Retardancy Relationships N2 - Three novel liquid ethyl (diethoxymethyl)phosphinate derivatives (EDPs) were synthesized and incorporated into flexible polyurethane foams (FPUFs). The flame retardancy of FPUFs were evaluated by limiting oxygen index (LOI), vertical burning and cone calorimetry tests, and the results indicated the structure-flame retardancy relationship of EDPs. Among these EDPs, P-(diethoxymethyl)-N-phenylphosphonamidate (EDPPA) exhibited the best flame retardant effect, methyl 3-((diethoxymethyl)(ethoxy)phosphoryl)propanoate (EDPMA) the second, and ethyl phenyl (di-ethoxymethyl)phosphonate (EDPPO) the worst. When the incorporation of EDPPA was 10 wt%, the FPUFs could self-extinguish and pass the vertical burning test. Meanwhile, the LOI value of FPUF-PA increased to 23.6% with 20 wt% loading of flame retardant. According to the investigation of volatiles during the thermal degradation of FPUFs and the morphologies of char residues after cone test, we inferred the pos- sible flame retardant mechanism. The results indicated that EDPs could release phosphorus-containing compounds in the gas phase, which would generate phosphorus-containing radicals and play the role of radical scavenger. In the condensed phase, EDPs can promote the formation of dense, intact and thermal stably char layer on the surface of FPUFs. Moreover, we found that the structure influence on flame retardancy was attributed to the atoms linked to the central phosphorus. Our results indicate that these EDPs are promising flame retardants in FPUFs that can be applied to improve the flame retardancy of FPUFs in various practical applications. KW - Ethyl (diethoxymethyl)phosphinate derivatives KW - Flame retardant KW - Flexible polyurethane foam KW - Structure-flame retardancy relationship PY - 2021 DO - https://doi.org/10.1016/j.polymdegradstab.2021.109557 SN - 0141-3910 VL - 188 SP - 109557 PB - Elsevier Ltd. AN - OPUS4-53085 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Erning, Johann Wilhelm T1 - Risiken in der Trinkwasser-Installation: Das Regelwerk im Kontext von Planung, Bau und Betrieb N2 - Die Herangehensweise zur Bewertung von Risisken in der Trinkwasserinstallation im Zusammenhang mit den Vorgaben der neuen EU-Trinkwasserrihrlin werden diskutiert. Auswirkungen der Veränderungen auf die Wrkstoffauswahl werden gezeigt T2 - Die neue EU-Trinkwasserrichtlinie CY - Online meeting DA - 07.07.2021 KW - Korrosion KW - Trinkwasser-Installation KW - Hygiene PY - 2021 AN - OPUS4-52937 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wahab, M. A. A1 - Kebelmann, Katharina A1 - Schartel, Bernhard A1 - Griffiths, G. T1 - Improving bio-oil chemical profile of seaweeds through anaerobic fermentation pre-treatment N2 - Biomass pre-treatments for bio-oil quality improvement are mainly based on thermal and chemical methods which are costly and hence reduce the sustainability of pyrolysis-based refineries. In this paper, anaerobic digestion (AD) and dark fermentation (DF) are proposed as alternative ‘green’ pre-treatments to improve this situation. For this purpose, three seaweeds namely Sargassum polycystum, (Phaephyta), Gracilaria tenuistipitata, (Rhodophyta) and Ulva reticulata, (Chlorophyta) with high ash and oxygen contents were pre-treated to improve their composition and structure prior to pyrolysis. The results reveal that both biological pre-treatments affected, positively, the composition and structure of the seaweed biomass with AD pre-treatment reducing N and S contents by 86% and 63%, respectively. DF was more efficient in terms of ash and moisture reduction with 25% and 70%, respectively. In addition, oxygen (O) reduction by 27% was observed after DF which was evidenced by FTIR spectroscopy indicating the reduction of most oxygen-containing functional groups in the biomass. On the other hand, the carbon (C) content increased in DF pre-treated seaweeds up to 42%, almost two times higher relative content than C in the raw seaweed. The changes in the composition of pre-treated seaweeds resulted in changes in their thermal degradation and the volatile profiles produced during pyrolysis. Interestingly, anhydrosugars and furans which account for some 70% (by area) in raw seaweeds markedly declined or become undetectable after DF pre-treatment and correspondingly more acetic acid and hydrocarbons were produced while after AD more aromatics with high toluene content (ca.17%) were generated. The results indicate that biooil with profiles more similar to petroleum-based composition i.e. rich in hydrocarbons and low in anhydrosugars, N and S can be generated by AD and DF pre-treatments and opens up the possibility of these approaches to effect cost reduction in the overall generation of bio-based fuels. KW - Anaerobic digestion KW - Dark fermentation KW - Pyrolysis KW - Seaweeds KW - Thermogravimetric analysis KW - Pyrolysis volatiles PY - 2021 DO - https://doi.org/10.1016/j.enconman.2021.114632 SN - 0196-8904 VL - 245 SP - 1 EP - 12 PB - Elsevier CY - Amsterdam AN - OPUS4-53136 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Zhang, W.-H. A1 - Qin, J. A1 - Lu, D.-G. A1 - Thöns, Sebastian A1 - Havbro Faber, M. T1 - Vol-informed decision-making for SHM system arrangement N2 - Structural health monitoring systems have been widely implemented to provide real-time continuous data support and to ensure structural safety in the context of structural integrity management. However, the quantification of the potential benefits of structural health monitoring systems has not yet attracted widespread attention. At the same time, there is an urgent need to develop strategies, such as optimizing the monitoring period, monitoring variables, and other factors, to maximize the potential benefits of structural health monitoring systems. Considering the continuity of structural health monitoring information, a framework is developed in this article to support decision-making for structural Health monitoring systems arrangement in the context of structural integrity management, which integrates the concepts of value of information and risk-based inspection planning based on an approach which utilizes a conjugate prior probability distribution for updating of the probabilistic models of structural performances based on structural health Monitoring information. An example considering fatigue degradation of steel structures is investigated to illustrate the application of the proposed framework. The considered example shows that the choice of monitoring variables, the Monitoring period, and the monitoring quality may be consistently optimized by the application of the proposed framework and approach. Finally, discussions and conclusions are provided to clarify the potential benefits of the proposed Framework with a special view to practical applications of structural health monitoring systems. KW - Value of information KW - Structural health monitoring systems arrangement strategy KW - Structural integrity management KW - Rskbased inspection KW - Structural health monitoring information model PY - 2020 DO - https://doi.org/10.1177/1475921720962736 SN - 1475-9217 VL - 21 IS - 1 SP - 37 EP - 58 PB - SAGE Journals CY - USA AN - OPUS4-53064 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Wagner, Adrian T1 - Auslagerung von nichtrostenden Stählen in Straßentunneln - Stand nach 3 Jahren N2 - Im Sinne einer mittel- bis langfristigen Reduktion wartungsbedingter Verkehrsbeeinflussungen in Tunnelbauwerken ist es von Bedeutung, die intensiven und aufwendigen Reinigungs- und Pflegearbeiten für Ein- und Anbauteile aus nichtrostendem Stahl in Straßentunneln zu reduzieren. Unter diesem Aspekt besteht großes Interesse die Einsatzmöglichkeiten alternativer nichtrostender Stähle, zu den bislang gebräuchlichen nichtrostenden austenitischen Stählen 1.4404 und 1.4571, zu eruieren. In dem Forschungsprojekt geht es um die Qualifizierung nichtrostender ferritisch austenitischer Stähle (Duplexstahl) in Straßentunneln. Diese verfügen im Vergleich zu austenitischen Stählen über eine doppelt so hohe Festigkeit bei gleichzeitig hoher Korrosionsbeständigkeit. In dieser Präsentation werden die Auslagerungsergebnisse nach 3 Jahren vorgestellt. T2 - Vorstellung der 3 Jahres Ergebnisse beim VDEh in Düsseldorf CY - Düsseldorf DA - 04.08.2021 KW - Duplex KW - Tunnelbauwerke KW - Korrosion KW - Korrosivität KW - Straßentunnel KW - Lean-Duplex PY - 2021 AN - OPUS4-53068 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Wiehle, Philipp A1 - Brinkmann, M. T1 - Tragfähigkeit von Lehmmauerwerk - Experimentelle und numerische Analyse T1 - Load-bearing capacity of earth masonry – An experimental and numerical analysis N2 - Die Bemessung von tragendem Lehmmauerwerk erfolgt in Deutschland auf Basis der Lehmbau Regeln. Das dort verankerte Nachweisverfahren beruht auf einem globalen Sicherheitskonzept, welches aus zuverlässigkeitstheoretischer Sicht nicht mehr dem Stand der Technik entspricht. Auf Grund dessen wird das Bemessungskonzept für Lehmmauerwerk vom Deutschen Institut für Bautechnik (DIBt) voraussichtlich 2023 außer Kraft gesetzt. Ein statischer Nachweis von tragenden Lehmbauten wäre in Deutschland dann ausschließlich mit einer Zustimmung im Einzelfall (ZiE) oder vorhabenbezogener Bauartgenehmigung (vBg) möglich. Beides ist mit erheblichem Mehraufwand und höheren Kosten verbunden, was für den Lehmmauerwerksbau einen entscheidenden Nachteil im Vergleich zum konventionellen Mauerwerksbau darstellt. Um eine unkomplizierte Praxisanwendung von Lehmmauerwerk zu ermöglichen, werden innerhalb eines Forschungsvorhabens, welches von der Bundesanstalt für Materialforschung und -prüfung (BAM), dem Institut für Massivbau der Technischen Universität Darmstadt sowie dem Ingenieurbüro ZRS durchgeführt wird, auf Basis der Produktnormen für Lehmsteine und Lehmmauermörtel Grundlagen für ein aktualisiertes Bemessungskonzept entwickelt. Im Rahmen des Projekts wird ebenfalls untersucht, inwiefern die Bemessungsregeln nach den vereinfachten Berechnungsmethoden für unbewehrtes Mauerwerk gemäß DIN EN 1996-3 / NA auf den Lehmmauerwerksbau übertragbar sind. Falls eine Anwendung des normativen Nachweisverfahrens bei Lehmmauerwerk möglich ist, wäre zukünftig eine Aufnahme von Lehmsteinen und Lehmmauermörtel in den nationalen Anhang des Eurocode 6 denkbar, was eine bedeutsame Erweiterung des Anwendungsbereichs von Lehmmauerwerk zur Folge hätte. Diverse wissenschaftliche Untersuchungen konnten zeigen, dass bemessungsrelevante Festigkeits- und Verformungseigenschaften von Lehmmauerwerksbaustoffen stark von der vorherrschenden Materialfeuchte abhängen, welche im hygroskopischen Wassergehaltsbereich im Wesentlichen von der relativen Luftfeuchte (RLF) bestimmt wird. Auch die Zwischenergebnisse des laufenden Forschungsvorhabens zur Entwicklung eines Bemessungskonzepts für Lehmmauerwerk ergaben eine deutlich erkennbare Abhängigkeit zwischen der Materialfeuchte und den relevanten Festigkeits- und Verformungseigenschaften. Eine detaillierte Kenntnis des feuchteabhängigen Materialverhaltens von Lehmsteinen, -mörtel und -mauerwerk ist zwingend erforderlich, um ein konsistentes und zuverlässiges Bemessungskonzept für Lehmmauerwerk zu entwickeln. Im Rahmen des laufenden Forschungsprojektes werden deshalb umfangreiche Versuche zum Drucktragverhalten von Lehmsteinen und -mörtel sowie Lehmmauerwerk nach Konditionierung bei unterschiedlichen RLF durchgeführt und analysiert. Weiterhin werden auf Basis der experimentellen Ergebnisse numerische Modelle kalibriert, welche die detaillierte Analyse der Biegedrucktragfähigkeit von Lehmmauerwerk ermöglichen. In diesem Beitrag werden zunächst die bisherigen Zwischenergebnisse bezüglich der experimentell ermittelten feuchteabhängigen Materialkennwerte von Lehmsteinen, -mörtel und -mauerwerk dargelegt. Darauf aufbauend werden numerische Untersuchungen zur Bestimmung der Systemtragfähigkeit von Lehmmauerwerk unter Feuchteeinflusses durchgeführt und erläutert. N2 - The structural design of load-bearing earthen masonry in Germany is based on the Lehmbau Regeln. The verification procedure outlined in these regulations is based on a global safety concept that no longer corresponds to the state of the art from a reliability theory perspective. As a result, the structural design concept for earthen masonry will most likely be discontinued by the German Institute for Building Technology (DIBt) in 2023. A structural verification of load-bearing earthen buildings would then only be possible in Germany with an approval for individual cases (ZiE) or a project-related permit type (vBg). Both methods are associated with considerable additional work and higher costs, which is a decisive disadvantage for earthen masonry construction compared to conventional masonry construction. In order to enable a straightforward practical application of earthen masonry, the Federal Institute for Materials Research and Testing (BAM), the Institute for Solid Construction of the Technical University of Darmstadt and ZRS Engineers are laying the groundwork for an updated structural design concept based on the product standards for earth blocks and earthen masonry mortar. The project will also investigate the extent to which the design rules based on the simplified calculation methods for unreinforced masonry according to DIN EN 1996-3 / NA can be transferred to earthen masonry construction. If the normative verification procedure can be applied to earthen masonry, it would be conceivable to include earth blocks and earthen masonry mortar in the national appendix of Eurocode 6 in the future, which would result in a significant expansion of the field of application of earthen masonry. Various scientific studies have shown that the strength and deformation properties of earthen masonry building materials relevant to structural design are strongly dependent on the prevailing material moisture level, which is essentially determined by the relative humidity (RH) in the hygroscopic water content range. The interim results of the current research project for the development of a structural design concept for earthen masonry also showed a clearly recognisable dependency between the material moisture level and the relevant strength and deformation properties. Detailed knowledge of the moisture-dependent material behaviour of earth blocks, earthen mortar and masonry is absolutely essential to developing a consistent and reliable structural design concept for earthen masonry. Within the framework of the current research project, extensive tests on the pressure load bearing capacity of earth blocks and earthen mortar as well as earthen masonry after conditioning at different RH levels are therefore being carried out and analysed. Furthermore, numerical models are being calibrated on the basis of the experiment results, which facilitate a detailed analysis of the bending pressure bearing capacity of earthen masonry. This paper presents, firstly, the interim results obtained so far concerning the experimentally determined moisture-dependent material characteristics of earth blocks, earthen mortar and masonry. Based on this material, numerical investigations for determining the system bearing capacity of earthen masonry under the influence of moisture are carried out and explained. T2 - LEHM 2020 CY - Weimar, Germany DA - 30.10.2020 KW - Lehm KW - Earth KW - Tragfähigkeit KW - Mauerwerk KW - Feuchte KW - Load-bearing KW - Moisture KW - Strength PY - 2020 SP - 1 EP - 12 PB - Dachverband Lehm CY - Weimar AN - OPUS4-53231 LA - mul AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Tabaka, Weronika A1 - Timme, Sebastian A1 - Lauterbach, Tobias A1 - Medina, L. A1 - Berglund, L. A. A1 - Carosio, F. A1 - Duquesne, S. A1 - Schartel, Bernhard T1 - Bench-scale fire stability testing - Assessment of protective systems on carbon fibre reinforced polymer composites N2 - Fire resistance testing of components made of carbon fibre reinforced polymers (CFRP) usually demands intermediate-scale or full-scale testing. A bench-scale test is presented as a practicable and efficient method to assess how different fire protective systems improve the structural integrity of CFRPs during fire. The direct flame of a fully developed fire was applied to one side of the CFRP specimen, which was simultaneously loaded with compressive force. Three different approaches (film, non-woven, and coatings) were applied: paper with a thickness in the range of μm consisting of cellulose nanofibre (CNF)/clay nanocomposite, nonwoven mats with thickness in the range of cm and intumescent coatings with a thickness in the range of mm. The uncoated specimen failed after just 17 s. Protection by these systems provides fire stability, as they multiply the time to failure by as much as up to 43 times. The reduced heating rates of the protected specimens demonstrate the reduced heat penetration, indicating the coatings’ excellent heat shielding properties. Bench-scale fire stability testing is shown to be suitable tool to identify, compare and assess different approaches to fire protection. KW - Fire stability KW - Bench-scale fire resistance KW - Carbon fibre reinforced polymer KW - Protective coatings PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-532401 DO - https://doi.org/10.1016/j.polymertesting.2021.107340 SN - 0142-9418 SN - 1873-2348 VL - 102 SP - 7340 PB - Elsevier CY - Amsterdam AN - OPUS4-53240 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schartel, Bernhard T1 - More Than the Sum of Its Parts: Multicomponent Flame Retardants N2 - Efficient flame retardancy is often achieved only when applying multicomponent systems. Flame retardants are combined or used together with adjuvants or synergists; fibres and fillers contribute to fire properties crucially. Multicomponent systems are discussed in their capacity as general and powerful strategy for achieving and optimizing flame retardant polymeric materials. T2 - 18th European Meeting on Fire Retardant Polymeric Materials, FRPM21 CY - Budapest, Hungary DA - 29.08.2021 KW - Fire Retardant KW - Synergy KW - Pseudo-synergy KW - Filler KW - Fibre reinforced polymers KW - Dripping Agent KW - Adjuvant KW - Synergist KW - Charring Agent KW - Mode of Action PY - 2021 AN - OPUS4-53198 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Chan, Yin Yam T1 - Flame retardant flexible polyurethane foams using phosphorous soybean-oil-based polyol and expandable graphite N2 - A phosphorous soybean-oil-based polyol was synthesized, successfully incorporated into flexible polyurethane foam (FPUF) and synergistically combined with expandable graphite. T2 - 18th European Meeting on Fire Retardant Polymeric Materials, FRPM21 CY - Budapest, Hungary DA - 29.08.2021 KW - Bio-based KW - Polyurethane KW - Foam KW - Expandable graphite KW - Synergy PY - 2021 AN - OPUS4-53199 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Pospiech, D. T1 - New halogen-free flame retardants for rigid PIR foams: Efficient reduction of heat emission and improvement of char formation N2 - Effective flame retardancy is indispensable in almost all applications of thermally insulating foams in building & construction. The trend to halogen-free materials requires new solutions and proper understanding of structure-activity relationships. Here, we contribute investigations on halogen-free FRs for rigid PIR foams and compare different FRs: isocyanate-reactive vs non-reactive, phosphinate (DOPO) vs phosphonate (BPPO) vs phosphate. It is demonstrated that the chemical structure of the FRs has significant effects on heat emission and char formation. T2 - 18th European Meeting on Fire Retardant Polymeric Materials, FRPM21 CY - Budapest, Hungary DA - 29.08.2021 KW - PIR foams KW - Phosphorus flame retardants PY - 2021 AN - OPUS4-53200 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Falkenhagen, Sandra F. T1 - Flame Retardant Properties of Kenaf Fibre-reinforced Bio Epoxy Composites N2 - A commercially available bio epoxy resin with kenaf fibers and halogen free inorganic and organic flame retardants, respectively, is investigated concerning its thermal stability and fire performance. Particular attention has been paid to the difference of short fibers, fiber mats and woven materials. T2 - 18th European Meeting on Fire Retardant Polymeric Materials, FRPM21 CY - Budapest, Hungary DA - 29.08.2021 KW - Bio-composite KW - Thermoset KW - Phosphorus flire retardant KW - Kenaf PY - 2021 AN - OPUS4-53201 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sánchez-Olivares, Guadalupe T1 - Imparting Intumescent Flame Retardancy During the Tanning of Leather N2 - FR additives were incorporated during tanning process. The mode of action of an intumescent system and each component individually, was methodically investigated in a semi-finished leather. Vertical flammability test results showed that the investigated semi-finished leather satisfies the regulations of the Federal Aviation Administration; in addition, afterglow time is strong minimized and forced fire behavior pointed out an important reduction on smoke production. T2 - 18th European Meeting on Fire Retardant Polymeric Materials, FRPM21 CY - Budapest, Hungary DA - 29.08.2021 KW - Leather KW - Fire retardant KW - Intumescence KW - Smoke PY - 2021 AN - OPUS4-53203 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hupp, Vitus T1 - Adhesive Tapes in Construction and Passenger Transport - Blessing of Curse in Fires? N2 - The influence of pressure sensitive adhesive (PSA) tapes as adhesive layers on the burning behaviour of bonded materials has been investigated. Single-sided tapes as an outer connection between construction materials have large influence on flammability, flame spread and fire resistance. In contrast, double sided tapes only take a small impact on the flammability but can drasticly change the burning behaviour in developing fires. T2 - 18th European Meeting on Fire Retardant Polymeric Materials, FRPM21 CY - Budapest, Hungary DA - 29.08.2021 KW - Adhesive KW - Fire Retardant KW - Pressure sensitive adhesive (PSA) KW - Flammability PY - 2021 AN - OPUS4-53204 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Battig, Alexander T1 - Waste not, Want not: Leather Industrial Waste as a Fire Retardant Adjuvant in EVA N2 - An interesting fire retardant behavior of leather wastes collected from local tannery industry was observed in a detailed study on morphological, pyrolysis, forced combustion, flammability, mechanical and rheological properties. T2 - 18th European Meeting on Fire Retardant Polymeric Materials, FRPM21 CY - Budapest, Hungary DA - 29.08.2021 KW - Leather KW - Industrial waste KW - Circular economy KW - Bio-filler KW - Sustainability KW - Ethylene vinyl acetate PY - 2021 AN - OPUS4-53205 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Korwitz, A. T1 - Flame retardant polyesters with DOPO building blocks N2 - Polyesters with DOPO substituents can be successfully synthesized with 10-[2,5-Bis(2-hydroxyethoxy)phenyl]-9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide(DOPO-HQ-glycolether) and DOPO-substituted dimethyl succinate (PIta). These polyester materials show an effective flame retardancy which can be fine-tuned by the chemical structure of the polyester backbone. T2 - 18th European Meeting on Fire Retardant Polymeric Materials, FRPM21 CY - Budapest, Hungary DA - 29.08.2021 KW - DOPO KW - Polyester KW - Fire retardant PY - 2021 AN - OPUS4-53206 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Babutzka, Martin T1 - BAM-Meerwassercontainer – Konzept und zukünftige Forschungsideen N2 - Dieser Vortrag gibt einen Einblick in das Konzept und den Aufbau des BAM-Meerwassercontainers. Es werden Ergebnisse aus laufenden Messreihen gezeigt. T2 - Sitzung der DECHEMA/GfKORR-Fachgruppe "Mikrobielle Materialzerstörung und Materialschutz" CY - Online meeting DA - 10.11.2021 KW - Korrosionsprüfung KW - Kathodischer Korrosionsschutz KW - Mariner Bewuchs PY - 2021 AN - OPUS4-53730 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schneider, Ronald T1 - A risk-based framework for optimizing inspection and maintenance of deteriorating structures monitored by vibration-based monitoring systems N2 - In this presentation, a framework for integrating vibration-based structural health monitoring data into the optimization of inspection and maintenance of deteriorating structural systems is presented. The framework is demonstrated in an illustrative example considering a steel frame subject to fatigue. T2 - EERA JP Wind WORKSHOP on Ongoing research in offshore wind structures CY - Online meeting DA - 16.09.2021 KW - Structural Health Monitoring KW - Inspection KW - Maintenance KW - Deterioration KW - Vibration KW - Structural Systems PY - 2021 AN - OPUS4-53749 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Auersch, Lutz T1 - Resonances of railway bridges analysed in frequency domain by the modal-force-excitation, bridge-transfer and axle-sequence spectra N2 - In this article, the passage of different trains over different bridges will be studied for resonant excitation. The intensity of the resonance will be estimated in frequency domain by using three separated spectra. At first, the excitation spectrum of the modal forces is built by the mode shape and the passage time of the train over the bridge. The second spectrum is the frequency response function of the bridge which include the modal frequency, damping and mass. The third part is the spectrum of the axle sequence of the train. The influences of train speed, bridge length, bridge support, track irregularities, and train type on the resonance amplitudes will be analysed for each of these spectra separately for getting a better insight. A variety of axle-sequence spectra and corresponding rules will be presented for different vehicles and trains. As examples, the passage of a slow freight train over a long-span bridge, a normal passenger train over a medium-span bridge, and a high-speed train over a short bridge will be analysed. Corresponding measurements show the amplification, but also the cancellation of the subsequent axle responses. Namely in one of the measurement examples, the first mode of the bridge was amplified and the second mode was cancelled at a low speed of the train and vice versa at a higher speed. KW - Railway bridge KW - Bridge vibration KW - Train passage KW - Axle sequence KW - Resonance KW - Cancellation KW - Fequency domain PY - 2021 DO - https://doi.org/10.1016/j.engstruct.2021.113282 SN - 0141-0296 VL - 249 SP - 1 EP - 9 PB - Elsevier Ltd. CY - London AN - OPUS4-53766 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Wagner, Adrian T1 - Korrosionsmonitoring bei der Instandsetzung von chloridbelasteten Stahlbetonwerken N2 - In der aktuellen RL-SIB (DAfStB) wie auch in der TR Instandsetzung (DIBt) ist bei Anwendung des Instandsetzungsprinzips W-CL der Erfolg der Maßnahme durch Einbau und Messung von Korrosionsstromsensoren gefordert. Art und Aufbau der Sensoren sowie Kriterien zur Bewertung der Ergebnisse gibt es nicht. Ziel ist die Ausarbeitung eines Regelwerks-Entwurfes für die Art und den Aufbau von Korrosionsmonitoring-Systemen sowie für Kriterien zur zuverlässigen Bewertung der Messergebnisse, mit denen der Erfolg bei verschiedenen Instandsetzungskonzepten überprüft werden kann. T2 - 3. PA Sitzung WIPANO Projekt KoMICS CY - Berlin, Germany DA - 17.11.2021 KW - Korrosion KW - Korrosionsmonitoring KW - Sensoren KW - Chloridhaltiger Beton KW - Instandhaltung PY - 2021 AN - OPUS4-53782 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Chan, Yin Yam A1 - Ma, C. A1 - Zhou, F. A1 - Hu, Y. A1 - Schartel, Bernhard T1 - A liquid phosphorous flame retardant combined with expandable graphite or melamine in flexible polyurethane foam N2 - A systematic series of flexible polyurethane foams (FPUF) with different concentrations of flame retardants, bis([dimethoxyphosphoryl]methyl) phenyl phosphate (BDMPP), and melamine (MA) or expandable graphite (EG) was prepared. The mechanical properties of the FPUFs were evaluated by a universal testing machine. The pyrolysis behaviors and the evolved gas analysis were done by thermogravimetric analysis (TGA) and TGA coupled with Fourier-transform infrared (TG-FTIR), respectively. The fire behaviors were studied by limiting oxygen index (LOI), UL 94 test for horizontal burning of cellular materials (UL 94 HBF), and cone calorimeter measurement. Scanning electronic microscopy (SEM) was used to examine the cellular structure's morphology and the postfire char residue of the FPUFs. LOI and UL 94 HBF tests of all the flame retarded samples show improved flame retardancy. BDMPP plays an essential role in the gas phase because it significantly reduces the effective heat of combustion (EHC). This study highlights the synergistic effect caused by the combination of BDMPP and EG. The measured char yield from TGA is greater than the sum of individual effects. No dripping phenomenon occurs during burning for FPUF-BDMPP-EGs, as demonstrated by the result of the UL 94 HBF test. EG performs excellently on smoke suppression during burning, as evident in the result of the cone calorimeter test. MA reduces the peak heat release rate (pHRR) significantly. The synergistic effect of the combination of BDMPP and EG as well as MA offers an approach to enhance flame retardancy and smoke suppression. KW - Bis([dimethoxyphosphoryl]methyl) phenyl phosphate KW - Expandable graphite KW - Flexible polyurethane foam KW - melamine KW - phosphorous flame retardant PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-541840 DO - https://doi.org/10.1002/pat.5519 SN - 1099-1581 VL - 33 IS - 1 SP - 326 EP - 339 PB - Wiley AN - OPUS4-54184 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Marti, J. A1 - Schartel, Bernhard A1 - Oñate, E. T1 - Simulation of the burning and dripping cables in fire using the particle finite element method N2 - The behavior of the cable jacket in fire characterized by the tendency to melt and drip constitutes a major source of fire hazard. The reason is that the melted material may convey the flame from one point to another, expanding fire and contributing to the fire load. In this article, the capability of a new computational strategy based on the particle finite element method for simulating a bench-scale cables burning test is analyzed. The use bench-scale test has been previously used to simulate the full-scale test described in EN 50399. As the air effect is neglected, a simple combustion model is included. The samples selected are two cables consisting of a copper core and differently flame retarded thermoplastic polyurethane sheets. The key modeling parameters were determined from different literature sources as well as experimentally. During the experiment, the specimen was burned under the test set-up condition recording the process and measuring the temperature evolution by means of three thermocouples. Next, the test was reproduced numerically and compared with a real fire test. The numerical results show that the particle finite element method can accurately predict the evolution of the temperature and the melting of the jacket. KW - Dripping behavior KW - Particle finite element method KW - Cables in fire KW - Fire behavior KW - Fire simulation KW - Cable bundle PY - 2022 DO - https://doi.org/10.1177/07349041211039752 SN - 0734-9041 VL - 40 IS - 1 SP - 3 EP - 25 PB - Sage AN - OPUS4-54185 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz T1 - Die Berechnung der Einfügedämmung bei Schienenfahrwegen – die Impedanzmethode mit einem Freiheitsgrad N2 - Mit dieser Methode kann man die Einfügedämmung eines Schienenstützpunkts/einer Schwelle korrekt berechnen. Sie gilt in ihrer ursprünglichen Form für eine Unterschottermatte in einem Tunnel T2 - Norm-Arbeitsausschuss Schwingungsminderung in der Umgebung von Verkehrswegen CY - Online meeting DA - 20.1.2022 KW - Impedanzmethode KW - Elastische Elemente KW - Schienenfahrweg PY - 2022 AN - OPUS4-54243 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Erning, Johann Wilhelm T1 - Bauteile aus additiv gefertigtem Werkstoff 1.4404 in der Trinkwasserinstallation N2 - Elektrochemische Messungen zur hygienischen Bewertung additiv gefertigter Bauteile werden diskutiert. Die Bewertung und Details des Werkstoffs werden beschrieben, Anwendungsbeispiele gezeigt. T2 - GfKORR AK Eisen und Stahl CY - Online meeting DA - 14.12.2021 KW - Korrosion KW - Trinkwasser KW - Hygienische Bewertung KW - Additive Fertigung PY - 2021 AN - OPUS4-54024 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Burkert, Andreas T1 - Abschluss des WIPANO-Vorhabens GELELEK N2 - Der Vortrag vermittelt dem betreuenden DIN Normenausschuss NMP 177 einen Gesamtüberblick über das abgeschlossene WIPANO-Vorhaben "Normenentwurf für ein Prüfverfahren zur Bestimmung von Deckschichtwiderständen an Zinküberzügen mittels gelartiger Elektrolyte (GELELEK). Innerhalb des Vorhabens wurden die elektrochemischen Methoden und die Verfahrensparameter systematisch untersucht, ein Messsystem für Feldanwendungen entwickelt, ein Ringversuch mit über 20 Teilnehmern durchgeführt und ein Normenvorschlag erarbeitet. Die Förderzeile der Initiative WIPANO wurden erreicht. Die Erarbeitung eines auf den Ergebnissen beruhenden Normenentwurfs wird auf der nächsten Sitzung des NMP 177 gestartet. T2 - Normungssitzung NMP_177 AA CY - Online meeting DA - 21.10.2021 KW - Korrosionsschutz KW - Zinküberzug KW - Deckschichtwiderstand KW - Gelartige Elektrolyte PY - 2021 AN - OPUS4-54090 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Wachtendorf, Volker A1 - Schartel, Bernhard A1 - Lin, Xuebao A1 - Tan, Yi A1 - Schoch, R. A1 - Lang, M. A1 - Tröppner, O. A1 - Bosse, M. ED - Ziegahn, K.-F. T1 - Untersuchung der Witterungsbeständigkeit komplexer Funktionalitäten von Polymerwerkstoffen durch künstliche Bewitterung: Flammschutz N2 - In den letzten Jahrzehnten wurde die Degradation der polymeren Matrix von flammgeschützten Polymeren eingehend untersucht. Erst in den letzten Jahren jedoch hat sich die Frage der Lebensdauer der Funktionalität des Flammschutzes selbst als wichtige Fragestellung herauskristallisiert, z.B. bei Kabeln. Deshalb sollte diese Fragestellung durch systematisch-variierte künstliche Klima- und Bewitterungstests an flammgeschützten Polymerwerkstoffen untersucht werden. T2 - 50. Jahrestagung der Gesellschaft für Umweltsimulation (GUS) CY - Online meeting DA - 23.03.2022 KW - Flammschutz, Witterungsbeständigkeit, Langzeitbeständigkeit, UV, E&E PY - 2022 SN - 978-3-9818507-7-2 VL - 50 SP - 143 EP - 148 CY - Pfinztal (Berghausen) AN - OPUS4-54543 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wahab, M. A. A1 - Kebelmann, Katharina A1 - Schartel, Bernhard A1 - Griffiths, G. T1 - Valorization of macroalgae digestate into aromatic rich bio-oil and lipid rich microalgal biomass for enhanced algal biorefinery performance N2 - The valorization of macroalgae digestate as a secondary resource for high value chemicals and nutrients will promote the sustainability and circularity of anaerobic digestion based biorefinery. In this study, three digestates from A. nodosum C.linum and L. digitata were separated into liquid and solid fractions to investigate the production of high value added chemicals through pyrolysis using Pyrolysis Gas Chromatography Mass Spectroscopy (Py-GC/MS) while the filtered liquid fractions were tested as an alternative culture media to grow C. sorokiniana under mixotrophic conditions. The digestates showed different thermal degradation and an improvement of bio-oil profiles compared to the starter material. Pyrolyzates from raw macroalgae were characterized by a high anhydrosugar content in contrast to high aromatics observed in the case of their digestates. Toluene, benzofuran and vinylphenol, base chemicals for many industries, represented together 30–37% of the total chemicals produced during pyrolysis of the three macroalgae digestate. On the other hand, C. sorokiniana cultured on digestate-based media showed a higher lipid content with an increase in monounsaturated fatty acids and a lower poly-unsaturated fatty acid content in comparison to microalgae grown in standard tris-acetate-phosphate media. Thus, the acyl composition was shifted in a direction more suitable for biodiesel production by this process. In addition, the increase of Chemical Oxygen Demand and Volatile Fatty Acids concentration in the digestate was found to reduce ammonium toxicity. Finally, 94% of Chemical Oxygen Demand and 83% of ammonium were removed by microalgae from the digestate-based media which will reduce the pollution risk of the biorefinery. Overall, the results indicate that using macroalgae solid digestates can generate improvements in the quality of products obtained by pyrolysis and the liquid digestate can positively influence microalgae growth and its products. KW - Macroalgae KW - Anaerobic digestion KW - Aromatics KW - Microalgae culture KW - Biorefinery PY - 2022 DO - https://doi.org/10.1016/j.jclepro.2022.130925 SN - 0959-6526 VL - 341 SP - 1 EP - 10 PB - Elsevier Ltd. AN - OPUS4-54365 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Babutzka, Martin T1 - Update nach 10 Jahren Bewitterung - Langzeitkorrosionsverhalten nichtrostender Stähle in maritimer Atmosphäre N2 - Durch Fortführung der Untersuchungen aus einem Forschungsvorhaben wurden neun verschiedene Stahllegierungen unter maritimen Umgebungsbedingungen über zehn Jahre ausgelagert und deren Korrosionsverhalten untereinander verglichen und bewertet. Anhand der Ergebnisse der Auslagerungsprüfungen konnten Rückschlüsse auf die Einflüsse der Legierungszusammensetzung, der Oberfächenausführung und der Auslagerungszeit unter maritimen Auslagerungsbedingungen gewonnen werden. Die Proben der drei untersuchten Duplexwerkstoffe zeigten über den Auslagerungszeitraum von zehn Jahren sowohl mit als auch ohne Spaltgeometrie die beste Korrosionsbeständigkeit. Ebenso konnte der molybdänlegierte Ferrit 1.4521 eine vergleichbar gute Korrosonsbeständigkeit erzielen, wie die klassischen austenitischen Werkstoffe 1.4301 und 1.4404. T2 - Korrosionsschutz in der maritimen Technik 2022 CY - Online meeting DA - 27.01.2022 KW - Auslagerungsversuche KW - Korrosionsschutz KW - Korrosion KW - Nichtrostende Stähle PY - 2022 AN - OPUS4-54276 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Rütters, H. A1 - Fischer, S. A1 - Le, Quynh Hoa A1 - Bettge, Dirk A1 - Bäßler, Ralph A1 - Maßmann, J. A1 - Ostertag-Henning, C. A1 - Wolf, J. L. A1 - Pumpa, M. A1 - Lubenau, U. A1 - Knauer, S. A1 - Jaeger, P. A1 - Neumann, A. A1 - Svensson, K. A1 - Pöllmann, H. A1 - Lempp, C. A1 - Menezes, F. F. A1 - Hagemann, B. T1 - Towards defining reasonable minimum composition thresholds – Impacts of variable CO2 stream compositions on transport, injection and storage N2 - To set up recommendations on how to define “reasonable minimum composition thresholds” for CO2 streams to access CO2 pipeline networks, we investigated potential impacts of CO2 streams with different and temporally variable compositions and mass flow rates along the CCS chain. All investigations were based on a generic “CCS cluster scenario” in which CO2 streams captured from a spatial cluster of eleven emitters (seven fossil-fired power plants, two cement plants, one refinery and one steel mill) are collected in a regional pipeline network. The resulting CO2 stream (19.78 Mio t impure CO2 per year) is transported in a trunk line (onshore and offshore) and injected into five generic replicate storage structures (Buntsandstein saline aquifers) offshore. Experimental investigations and modeling of selected impacts revealed beneficial as well as adverse impacts of different impurities and their combinations. Overall, no fundamental technical obstacles for transporting, injecting and storing CO2 streams of the considered variable compositions and mass flow rates were observed. We recommend to define minimum composition thresholds for each specific CCS project through limiting i) the overall CO2 content, ii) maximum contents of relevant impurities or elements, iii) acceptable variability of concentrations of critical impurities, and defining impurity combinations to be avoided. KW - Impurities KW - CO2 quality KW - Pipeline network KW - Whole-chain CCS scenario KW - Recommendations PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-543004 DO - https://doi.org/10.1016/j.ijggc.2022.103589 SN - 1750-5836 VL - 114 SP - 1 EP - 14 PB - Elsevier CY - New York, NY AN - OPUS4-54300 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Auersch, Lutz T1 - The role of vehicle dynamics in train-induced ground vibrations and the detection of irregular axle-pulse responses due to a varying track support stiffness N2 - Train-induced ground vibrations are all generated by the vehicle, by static or dynamic vehicle loads. The most important and most accepted excitation are the dynamic wheel loads from the passage over track irregularities. Dynamic wheel loads will be compared from parallel axle-box and ground vibration measurements at more than seven sites. Some low-frequency excitation of ground vibrations, typically between 10 and 30 Hz, cannot be found in the axle-box measurements. Therefore, other vehicle modes, such as rigid bogie modes, flexible carriage modes, rigid and flexible wheelset modes, have been analysed for additional excitation forces. These vehicle dynamics analyses give an explanation for higher axle-box results at high frequencies, but not for the excitation of the higher low-frequency ground-vibration component. Finally, the effect of the moving static train loads will be analysed. For a regular track and soil, the moving static train loads yield the quasi-static response which exists only in the low-frequency nearfield of the track. If the support stiffness is randomly varying along the track, the pulses on the track generate an additional low-frequency component which is called the irregular pulse responses. This component will be demonstrated by numerical analysis where all axle pulses are superposed in frequency domain. KW - Wheelset KW - Vehicle-track interaction KW - Rail roughness KW - Random dynamics and vibrations KW - Modal analysis PY - 2022 DO - https://doi.org/10.1177/09544097221086064 SN - 0954-4097 VL - 236 IS - 10 SP - 1218 EP - 1233 PB - Sage CY - London AN - OPUS4-55000 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wiehle, Philipp A1 - Simon, Sebastian A1 - Baier, J. A1 - Dennin, L. ED - Forde, M. T1 - Influence of relative humidity on the strength and stiffness of unstabilised earth blocks and earth masonry mortar N2 - Aim of this study is to provide information about moisture dependent material behaviour of unstabilised loadbearing earth blocks and mortars. Compressive strength and Young’s modulus were investigated after conditioning in varying relative humidity reaching from 40 % up to 95 %. The material composition and physical properties were investigated to understand the influence of relative humidity onto the mechanical properties. A normalisation of strength and stiffness by the values obtained at 23 ◦C and 50 % relative humidity reveals a linear dependence of compressive strength and Young’s modulus that is regardless of the material composition. Thus, it is possible to describe the influence of relative humidity onto the load-bearing behaviour of unstabilised earth masonry materials in a generally valid formulation. KW - Earth block masonry KW - Load-bearing behaviour KW - Compressive strength KW - Moisture content KW - Sorption isotherm PY - 2022 DO - https://doi.org/10.1016/j.conbuildmat.2022.128026 SN - 0950-0618 VL - 342 IS - Part A SP - 1 EP - 15 PB - Elsevier Ltd. AN - OPUS4-54949 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schartel, Bernhard T1 - Non-vegan flame-retardant (adjuvants in) biocomposites N2 - Emanating from developing flame retarded biocomposites, we have proposed renewable natural fibers (including keratin) taken from industrial waste as an authentic sustainable approach. More recently, we have investigated non-vegan flame retardant approaches. This paper loves to give you an insight into our ongoing projects on biogenic industrial wastes like leather, bone meal, and insects. Materials were characterized multi-methodically, flame retardant modes of action quantified, decomposition mechanism proposed, and synergisms explained. Considering the large quantities of leather waste (LW) in industrial-scale production, we underline LW as multifunctional bio-adjuvants. LW enhances the flame retardancy of poly(ethylene-vinyl acetate) (EVA) containing phosphorus flame retardants (P-FR). Products/by-products of the invertebrate and vertebrate farming, respectively, are promising bio-based adjuvants in flame retarded bio-epoxy thermosets. While the addition of bone meal yields the formation of an inorganic shield, protein-based powders from insects provide an intumescent behavior. In combination with a P-FR superior charring and self-extinguishing are obtained. Acknowledgement: In part of this work was supported by the Volkswagen Foundation grant “Experiment!” No. 97437. T2 - Fire and Polymers, workshop, ACS Division of Polymer Chemistry CY - Napa, California, US DA - 05.06.2022 KW - Fire behaviour KW - Renewable KW - Circular economy KW - Biocomposite PY - 2022 AN - OPUS4-55025 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Gleuwitz, F. Robert A1 - Battig, Alexander A1 - Schartel, Bernhard T1 - Tenebrio molitor Beetle as a “Nonvegan” Adjuvant to Flame Retardants in Tannic Acid-Based Epoxy Thermosets N2 - Material solutions that meet both circular bioeconomy policies and high technical requirements have become a matter of particular interest. In this work, a prospectively abundant proteinrich waste resource for the manufacturing of flame-retardant epoxy biocomposites, as well as for the synthesis of biobased flame retardants or adjuvants, is introduced. Different biomass fillers sourced from the cultivation of the mealworm beetle Tenebrio molitor are embedded in a bioepoxy resin cured with tannic acid and investigated regarding the fire performance of the thermosets. By means of spectroscopic and thermal analysis (attenuated total reflectance FTIR spectroscopy, thermogravimetric analysis-coupled FTIR spectroscopy, and differential scanning calorimetry), the influence of the biomass microparticles on the curing and thermal degradation behavior is evaluated. The final performance of the biocomposites is assessed based on fire testing methodology (limited oxygen index, UL-94, and cone calorimetry). Providing a high charring efficiency in the specific tannic acid-based epoxy matrix, the protein-rich adult beetle is further investigated in combination with commercial environmentally benign flame retardants in view of its potential as an adjuvant. The results highlight a char forming effect of nonvegan fillers in the presence of tannic acid, particularly during thermal decomposition, and point toward the potential of protein-based flame retardants from industrial insect rearing for future formulations. KW - Tannic acid KW - Flame retardancy KW - Sustainable KW - Epoxy resin KW - Insects PY - 2022 DO - https://doi.org/10.1021/acssuschemeng.2c00746 SN - 2168-0485 VL - 10 IS - 19 SP - 6313 EP - 6324 PB - ACS AN - OPUS4-54845 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schlick-Hasper, Eva A1 - Bethke, John A1 - Vogler, Nico A1 - Goedecke, Thomas T1 - Flow properties of powdery or granular filling substances of dangerous goods packagings - Comparison of the measurement of the angle of repose and the determination of the Hausner ratio N2 - To ensure safety when transporting dangerous goods, it is important to specify the flow properties of the respective solid filling substance of the packagings. For this purpose, the angle of repose is currently used for the UN approvals in Germany. Measurements were carried out on 12 powdery or granular substances applying the angle of repose measuring methods customary in the test centres. The results of the methods differ significantly from each other. In addition, some of the techniques cannot be applied for very cohesive or coarse-grained materials. The results for the angle of repose show a strong scatter for some constellations (coefficient of variation more than 20 %). Safety during transport of dangerous goods cannot be guaranteed with this currently practiced system of measuring the angle of repose. As a consequence, an alternative parameter to characterize the flow properties of bulk materials should be used in the recognized test centers for dangerous goods packagings, such as the Hausner ratio. This approach leads to more precise test results for the substances examined (maximum coefficient of variation 2.8 %). It also has advantages in terms of applicability and occupational safety. Since the flow properties are safety-relevant, both in terms of mechanical safety and safety against the release of dangerous substances, the testing practice in the recognized test labs should be improved and standardized. KW - Sift-proofness KW - Powders KW - Flowability KW - Flow properties KW - Angle of repose KW - Hausner ratio PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-552990 DO - https://doi.org/10.1002/pts.2678 SP - 1 EP - 18 PB - Wiley online library AN - OPUS4-55299 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hupp, Vitus T1 - Adhesive Tapes in Bonded Materials Fire Risk or Protective Layer? N2 - In the recent years, more and more products in construction and automotive industry are bonded by adhesive tapes instead of mechanical fasteners but there is no sufficient understanding of how these bonded, layered materials behave in fires. Our research project gives an insight of how adhesives and substrates interact with each other in different fire scenarios and how flame retardants function in pressure sensitive adhesive (PSA) tapes. A systematic investigation on the burning behavior of PSA tapes as free-standing films, as top layers on different substrates and as sandwich-like adhesive joints was performed. The burning behavior of free-standing PSA tapes and those used as a coating was significantly improved by using phosphorus-based flame retardants. Furthermore, it was shown that, depending on tape structure and substrate, the PSA tape can lower the fire risk by acting as an intermediate protection layer in bonded materials. T2 - Fire and Polymers CY - Napa, California, USA DA - 05.06.2022 KW - Pressure Sensitive Adhesives KW - Tapes KW - Fire Behavior KW - Bonded Materials PY - 2022 AN - OPUS4-55094 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz T1 - Elastische Elemente in der Emission, Transmission und Immission von Bahnerschütterungen N2 - Dieser Vortrag präsentiert einige Prinzipien und einige Beispiele zur Minderung von Eisenbahnerschütterungen. Die Prinzipien unterscheiden sich für die Minderungsmaßnahmen im Gleis, im Boden und bei Gebäuden. Kraftübertragungsfunktionen isolierter und nicht isolierter Gleissysteme, reflektierte und durchgelassene Wellenamplituden bei gefüllten Bodenschlitzen und die Übertragung der Freifeldschwingungen ins Gebäude werden analysiert. Bei den einfachen Gleismodellen muss der richtige Anteil der unabgefederte Fahrzeugmasse zum eindimensionalen Gleismodell hinzugefügt werden. Der Minderungseffekt eines gefüllten Bodenschlitzes ist von der Steifigkeit und nicht von der Impedanz des Schichtmaterials bestimmt. Bei einer elastischen Gebäudelagerung muss die Minderungswirkung mit der richtigen Boden- (Fundament-) Steifigkeit berechnet werden, und das abgeminderte Gebäudeverhalten hängt wesentlich von der effektiven Gebäudemasse ab, die mit zunehmender Frequenz deutlich kleiner als die starre Gebäudemasse ist. T2 - Norm-Arbeitsausschuss Schwingungsminderung in der Umgebung von Verkehrswegen CY - Bludenz, Austria DA - 17.5.2022 KW - Erschütterungsminderung KW - Bahngleis KW - Bodenschlitz KW - Gebäudelagerung KW - Elastische Elemente PY - 2022 AN - OPUS4-54916 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Chan, Yin Yam A1 - Schartel, Bernhard T1 - It Takes Two to Tango: Synergistic Expandable Graphite–Phosphorus Flame Retardant Combinations in Polyurethane Foams N2 - Due to the high flammability and smoke toxicity of polyurethane foams (PUFs) during burning, distinct efficient combinations of flame retardants are demanded to improve the fire safety of PUFs in practical applications. This feature article focuses on one of the most impressive halogen-free combinations in PUFs: expandable graphite (EG) and phosphorus-based flame retardants (P-FRs). The synergistic effect of EG and P-FRs mainly superimposes the two modes of action, charring and maintaining a thermally insulating residue morphology, to bring effective flame retardancy to PUFs. Specific interactions between EG and P-FRs, including the agglutination of the fire residue consisting of expanded-graphite worms, yields an outstanding synergistic effect, making this approach the latest champion to fulfill the demanding requirements for flame-retarded PUFs. Current and future topics such as the increasing use of renewable feedstock are also discussed in this article. KW - Synergy KW - Phosphorus-containing flame retardant KW - Expandable graphite KW - Polyurethane foams PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-551958 DO - https://doi.org/10.3390/polym14132562 SN - 2073-4360 VL - 14 IS - 13 SP - 2562 PB - MDPI AN - OPUS4-55195 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Babutzka, Martin A1 - et al., T1 - Exposure Site Catalogue - Catalogue of atmospheric corrosion field exposure sites in Europe N2 - Exposure sites and outdoor exposure have always been a part of atmospheric corrosion research providing the “final answer”, although at the cost of long exposure times. Individual exposure programs such as ISOCORRAG, MICAT and ICP Materials have resulted in collaborative networks of exposure sites. So far, however, there has been no collective effort to put together currently active sites in a comprehensive manner and across programs and nations. The information collected in the catalogue is possible thanks to the work of all individual site managers listed as contact persons, efforts of members of Working Party 25 (WP25) Atmospheric Corrosion of the European Federation of Corrosion (EFC) and financial support of the EFC. With this Catalogue you can both get a general overview of what is available and be guided if you are looking for a particular environment with certain characteristics. KW - Atmospheric Corrosion KW - Atmosphärische Korrosion KW - Corrosion KW - Korrosion KW - Exposure KW - Auslagerungsversuche PY - 2022 UR - https://efcweb.org/Scientific+Groups/WP25_+Atmospheric+Corrosion/Current+Activities/_/Exposure%20site%20catalogue%20EFC%20lores.pdf SP - 1 EP - 56 PB - European Federation of Corrosion, EFC AN - OPUS4-55284 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz T1 - Wave propagation from hammer, vibrator and railway excitation – theoretical and measured attenuation in space and frequency domain N2 - The attenuation of wave amplitudes is ruled by the planar, cylindrical or spher-ical geometry of the wave front (the geometric or power-law attenuation) but also by the damping of the soil (an exponential attenuation). Several low- and high-frequency filter effects are derived for the layering and the damping of the soil, for the moving static and the distributed train loads and for a homoge-neous or randomly heterogeneous soil. Measurements of hammer- and train-induced vibrations at five sites have been analysed for these attenuation and filter effects. The measured attenuation with distance can be discribed by gen-eralised power laws and some reasons will be discussed. The theoretical filter effects can well be found in the measurements. T2 - 10th Wave Mechanics and Vibration Conference (WMVC)nce CY - Lisbon, Potugal DA - 04.07.2022 KW - Hammer impact KW - Train passage KW - Layered soil KW - Attenuation KW - Filter effects KW - Randomly heterogeneous soil KW - Scattering PY - 2022 AN - OPUS4-55246 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hothan, Sascha T1 - Reaktive Brandschutzsysteme N2 - Die Präsentation gibt einen Überblick zum Anwendungsbereich und den -grenzen von reaktiven Brandschutzsystemen. Ferner werden Forschungsergebnisse der BAM vorgestellt. T2 - Stahlbau-Kalender-Tag 2022 CY - Stuttgart, Germany DA - 24.06.2022 KW - Reaktive Brandschutzsysteme KW - Feuerwiderstand KW - Stahlbau KW - Brandversuche KW - Dauerhaftigkeit PY - 2022 AN - OPUS4-55250 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Auersch, Lutz T1 - Different types of continuous track irregularities as sources of train-induced ground vibration and the importance of the random variation of the track support N2 - Irregularities of the track are a main cause of train-induced ground vibration, and track maintenance is of great importance. Although geometric irregularities at the wheel-rail contact are widely used, other types of irregularities, such as stiffness irregularities, irregularities from different track positions and irregularities in the wave propagation, were analysed in the present study. The track behaviour was investigated by a multi-beam-on-soil model. This track model is coupled with a vehicle model to calculate the vehicle–track interaction. The track model was also used for the track filtering, which transfers a track support error to the equivalent rail irregularity or, conversely, the sharp axle pulse on the rail to a smoother pulse on the soil. In the case in which this filtering varies randomly along the track, the pulses of the moving static load induce a certain ground Vibration component (“the scatter of axle pulses”). This effect was calculated by the superposition of axle pulses in the frequency domain and by a stochastic simulation. Simultaneous vehicle, track and soil measurements at a certain site were used to evaluate the different excitation and ground Vibration components. The agreement between calculations and axle-box and soil measurements is good. The ground vibrations calculated from rail irregularities and corresponding dynamic loads, however, clearly underestimate the measured ground vibration amplitudes. Only the static load that is moving over a varying track support stiffness can produce the important mid-frequency ground Vibration component by the scatter of axle pulses. KW - Train-induced ground vibration KW - Geometric vehicle and track irregularities KW - Stiffness variation KW - Multi-beam track model KW - Track filtering KW - Dynamic axle loads KW - Static axle loads KW - layered soil PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-543846 DO - https://doi.org/10.3390/app12031463 SN - 2076-3417 VL - 12 IS - 3 SP - 1 EP - 22 PB - MDPI CY - Basel AN - OPUS4-54384 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CHAP A1 - Schartel, Bernhard ED - Morgan, A.B. T1 - Multicomponent Flame Retardants N2 - The important take home message of this chapter: When multicomponent flame retardant systems are applied to polymeric materials, it becomes possible to address multiple fire properties, increase efficiency, and minimize flame retardant use to maximize polymer property balance. Flame retardants are combined or used together with adjuvants or synergists; fibers and fillers make a crucial contribution to their fire properties. Multicomponent systems are discussed in their capacity as an overall powerful strategy for achieving and optimizing non-halogenated flame-retardant polymeric materials. KW - Flame retardants KW - Synergy KW - Adjuvants KW - Fillers KW - Fibres PY - 2022 SN - 978-1-119-75056-7 SP - 413 EP - 474 PB - Scrivener Publishing LLC CY - Bevery ET - 2nd Edition AN - OPUS4-54426 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Aristia, Gabriela A1 - Le, Quynh Hoa A1 - Bäßler, Ralph T1 - Integrated Coating System for Corrosion Protection of Carbon Steel in Artificial Geothermal Brine N2 - Corrosive geothermal brines are a major challenge to geothermal power-plants. For cost reasons, plant designers prefer to use carbon and low alloyed steels, which are susceptible to uniform and localized corrosion when exposed to geothermal brines having acidic and saline properties. To solve such problem, coatings or inhibitors would be a protective solution as an alternative to the use of high alloyed materials. This study investigated a coating system consisting of polyaniline/silicon dioxide based on resources locally available in Indonesia. Protection against corrosion of carbon steel was shown by long-term (28 day) exposure and electrochemical tests of coated carbon steels, performed in an artificial acidic and saline geothermal brine, comparable to the conditions encountered at a site in Indonesia. Therefore, an integrated coating system is proposed for corrosion protection, combining the electrochemical functionality of polyaniline and the physical advantages of silica. T2 - AMPP International Corrosion Conference CY - Online meeting DA - 06.03.2022 KW - Geothermal KW - Corrosion KW - Coating KW - Polyaniline KW - Silicon dioxide PY - 2022 SP - 1 EP - 11 CY - Houston TX (USA) AN - OPUS4-54451 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bäßler, Ralph T1 - Integrated Coating System for Corrosion Protection of Carbon Steel in Artificial Geothermal Brine N2 - Corrosive geothermal brines are a major challenge to geothermal power-plants. For cost reasons, plant designers prefer to use carbon and low alloyed steels, which are susceptible to uniform and localized corrosion when exposed to geothermal brines having acidic and saline properties. To solve such problem, coatings or inhibitors would be a protective solution as an alternative to the use of high alloyed materials. This study investigated a coating system consisting of polyaniline/silicon dioxide based on resources locally available in Indonesia. Protection against corrosion of carbon steel was shown by long-term (28 day) exposure and electrochemical tests of coated carbon steels, performed in an artificial acidic and saline geothermal brine, comparable to the conditions encountered at a site in Indonesia. Therefore, an integrated coating system is proposed for corrosion protection, combining the electrochemical functionality of polyaniline and the physical advantages of silica. T2 - AMPP International Corrosion Conference 2022 CY - San Antonio, TX, USA DA - 08.03.2022 KW - Geothermal KW - Corrosion KW - Coating KW - Polyaniline KW - Silicon dioxide PY - 2022 AN - OPUS4-54452 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Erning, Johann Wilhelm ED - Leyens, C. T1 - Hygienische Eigenschaften von additiv gefertigtem 1.4404 in Trinkwasser N2 - Elektrochemische Messungen zur hygienischen Bewertung additiv gefertigter Bauteile werden diskutiert. Die Bewertung und Details des Werkstoffs werden beschrieben, Anwendungsbeispiele werden gezeigt. T2 - 3. Fachtagung Werkstoffe und Additive Fertigung CY - Dresden, Germany DA - 11.05.2022 KW - Korrosion KW - Trinkwasser KW - Hygienische Bewertung KW - Additive Fertigung PY - 2022 SN - 978-3-88355-423-2 SP - 126 EP - 127 PB - Deutsche Gesellschaft für Materialkunde (DGM) CY - Sankt Augustin AN - OPUS4-54933 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bäßler, Ralph T1 - Corrosion Effects on Materials Considered for CC(U)S Applications N2 - Commercially available carbon steels are suitable for compression and pipelines as long as moisture content and impurities are limited. (water 50 to 100 ppmv, SO2 and NO2 ca. 100 ppmv) Corrosion rates increase with increasing water content. (0.2 – 20 mm/a) Condensation of acids and therefore droplet formation is always possible, even at low water contents. A low SO2 content within the CO2-stream might be more important than a low water content. Cr13-steels showed a general susceptibility to shallow pitting and pitting. So, they seem to be not suitable for CCUS applications. Low alloyed steels showed better corrosion behavior (predictable uniform corrosion). For direct contact with saline aquifer fluids only high alloyed steels shall be used. T2 - EFC Webinar CY - Online Meeting (Chongqing, China) DA - 18.05.2022 KW - Corrosion KW - CO2 quality KW - CO2 KW - CCS KW - CCU KW - Pipeline PY - 2022 AN - OPUS4-54854 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Falkenhagen, Sandra F. T1 - black as hell, strong as death and sweet as love - pyrolyzed waste materials and cyclodextrins as effective filler in flame retarded epoxy composites N2 - Renewable alternatives for common thermoset resins are demanded to go for sustainability. The objective is to create a flame retarded epoxy resin from a commercial bio epoxy resin with halogen free inorganic and organic flame retardants, respectively. Alumina trihydrate, aluminum diethyl phosphinate, a DOPO-based phosphonamidate and ammonium polyphosphate seem to have promising performances. Properties are enhanced with different bio fillers: pyrolyzed cocoa shells and plant waste (provided by Otto A. Müller Recycling GmbH, thanks!), short fibers and nonwovens of the natural fiber kenaf, hydroxypropyl-ß-cyclodextrin and sulfobutylether-ß-cyclodextrin. Fire performance is investigated by cone calorimeter examinations, LOI and UL-94 ratings. Thermal analysis is given by TG-FTIR and DSC measurements. Combinations of flame retardants and bio-fillers lead to reduced PHRR and THR, reach V0 in UL-94 and have a significant increase in LOI of up to 37 vol.-%. 10 % ammonium polyphosphate with 10 % pyrolyzed cocoa shell performs best, builds a magnificent protective layer, and shows good intumescence. T2 - 3rd international conference on eco-friendly flame retardant additives and materials CY - Alès, France DA - 17.05.2022 KW - Epoxy resin KW - Flame retardant KW - Kenaf fiber KW - Pyrolyzed plant waste KW - Cyclodextrin PY - 2022 AN - OPUS4-54928 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Erning, Johann Wilhelm ED - Stojanovic, I. T1 - Hygienic assessment of SLM-printed stainless steel N2 - Electrochemical measurements for the hygienic assessment of additively manufactured products are discussed. The Assessment and details of the material are described, examples for the application are given. N2 - Elektrochemische Messungen zur hygienischen Bewertung additiv gefertigter Bauteile werden diskutiert. Die Bewertung und Details des Werkstoffs werden beschrieben, Anwendungsbeispiele gezeigt. T2 - Kormat 2022 CY - Online meeting DA - 26.04.2022 KW - Korrosion KW - Trinkwasser KW - Hygienische Bewertung KW - Additive Fertigung PY - 2022 SN - 1848-4255 SP - 21 EP - 25 PB - Proceedings of the Croatian Society for Material Protection CY - Zagreb AN - OPUS4-54932 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Häßler, Dustin A1 - Hothan, Sascha T1 - Performance of intumescent fire protection coatings applied to structural steel tension members with circular solid and hollow sections N2 - Intumescent fire protection coatings are used to improve the fire resistance of steel members. Due to slender cross-sections typically used for tension members, high demands are placed on the effectiveness and reliability of the intumescent coatings. This paper describes real-scale fire tests of intumescent coatings applied to steel tension members with circular solid and hollow sections. First, the current regulations for the application of intumescent coatings on steel tension members are discussed. After that, a comparison between the foaming behaviour and failure mechanisms of intumescent coatings applied to steel tension members with different cross-sections and loading conditions is given. Next, the experimental setup and procedure of the performed fire tests are presented. In addition, the influences of various parameters on the performance of the intumescent coating are analysed, including the geometry of the steel profile, dry film thickness of the intumescent coating, load utilisation level as well as the orientation of the member. Based on the theoretical considerations and results of the fire tests, it is evidenced that mechanically loaded fire tests are essential to assess accurately the contribution of intumescent fire protection coatings to the fire resistance of steel tension members with circular solid sections. KW - Fire tests KW - Intumescent coating KW - Reactive fire protection system KW - Steel KW - Tension members PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-548981 DO - https://doi.org/10.1016/j.firesaf.2022.103605 SN - 0379-7112 VL - 131 SP - 1 EP - 12 PB - Elsevier Ltd. AN - OPUS4-54898 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bäßler, Ralph T1 - Influence of brine components on materials performance in geothermal applications N2 - Significant Cu-deposition and ‑precipitation only occurred in combination with carbon steel. High-alloyed materials prevent the disturbing Cu-agglomeration. Pb-deposition and ‑precipitation only occurred in combination with carbon steel. No negative Pb-effect could be observed in combination with high-alloyed steels. High alloyed corrosion resistant alloys are suitable and shall be chosen for future design of the piping system, either in massive or in cladded form, if formation of crevices with non-metallic materials can be excluded! T2 - EUROCORR 2022 CY - Berlin, Germany DA - 28.08.2022 KW - Corrosion KW - Geothermal KW - Copper PY - 2022 AN - OPUS4-55624 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Zekhnini, Khalid T1 - Corrosion testing in a laboratory container: Corrosion testing with artificial seawater and sediment N2 - Electricity generation by offshore wind turbine generators (WTG) is an important pillar of the energy transition. Corrosion processes on WTGs pose a particular challenge with regard to safe operation over longer periods of time due to the highly corrosive conditions in the offshore area. BAM is therefore conducting research to ensure a safe operation of the turbines over their intended service life to protect people and the environment. In a joint research project, different corrosion-relevant areas of a WTG foundation structure were specifically simulated in test basins within a laboratory container. The aim of the work was, on the one hand, the gravimetric and electrochemical determination of corrosion rates in the different areas of an WTG that are relevant for cathodic corrosion protection (CCP): Underwater and sediment zone as well as the transition area between these two zones. Also, targeted tests were carried out under CCP. In addition, investigations regarding calcareous deposition during CCP were carried out on idealized specimens under laboratory conditions to better assess its influence on the protection process. The investigations were carried out in a laboratory container with different basins, which were filled with sand as sediment and artificial seawater according to ISO 15711and connected via a closed water circuit. The poster at EURCORR 2022 provides an overview of the investigations and the most important results. It will be evaluated, if a simulation of offshore corrosion conditions is possible to a certain extent in an idealized system with artificial seawater and sediment. T2 - EUROCORR 2022 CY - Berlin, Germany DA - 28.08.2022 KW - Corrosion KW - Corrosion Testing KW - Artificial Sea Water KW - Laboratory Container PY - 2022 AN - OPUS4-55664 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Valet, Svenja T1 - Determination of the corrosion product layer resistance on zinc samples by using gel electrolytes N2 - Crash barriers, railings, lamp posts, waste glass containers - these are just a few of the many examples of galvanized surfaces. They withstand wind and weather for decades, which is possible thanks to a protective layer made of corrosion products. When designing the atmospheric durability of galvanized components, a linear corrosion loss is assumed. In the past 30 years, however, the surrounding atmosphere has changed a lot. Due to the restriction of sulfur exhaust air, acid rain completely disappeared in Europe and Germany, which has a direct influence on the type and protective effect of the corrosion products. Under the influence of current atmospheric conditions, zinc layers are significantly more resistant and no longer show any linear corrosion loss. The established test methods cannot correctly map this change in neither short-term nor long-term tests and thus provide incorrect results. In order to solve this problem, a new measurement method was developed at BAM that can assess the protective effect of the formed surface layers in a minimally invasive manner without damaging the sample and in short test times. For this new method, gel electrolytes are used and the so-called corrosion product layer resistance RL, which is made up of various surface resistances, is measured electrochemically. As a single measurement, the surface layer resistance can provide information about the existing corrosion protection, while time-dependent measurements assess the stability of the layer. Thus, it is possible again to evaluate the corrosion protection layer. Furthermore, this method can also be used for field measurements on real components. T2 - EUROCORR 2022 CY - Berlin, Germany DA - 28.08.2022 KW - Corrosion KW - Corrosion Testing KW - Gel electrolytes KW - Zinc and galvanized samples KW - Corrosion product layer PY - 2022 AN - OPUS4-55688 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bäßler, Ralph T1 - Electrochemical behaviors of casing steel/mortar interface in CO2 saturated aquifer fluid N2 - To reveal the corrosion resistance of casing steel/mortar interface in CO2 injection condition, sandwich samples were prepared and exposed up to 20 weeks in aquifer fluid under 10 MPa and 60 °C. Cross section analysis revealed the crevice corrosion as main mechanism instead of pitting corrosion despite very high concentration of Cl in NGB. EDS element line scan analysis of the 20-week-exposed metal/mortar coupon showed Chloride distribution, which still not reached the metal/mortar interface, explaining no pitting was observed. It was confirmed that FeCO3 cannot protect the steel surface in CO2 saturated NGB. To verify the protective possibility of passivation happened on casing steel/mortar interface, simulated pore solution was synthesized and used to passivate the steel for 42 days. OCP and EIS confirmed the formation of passive layer. The 42 day passivated layer was broken during the first minute of exposure in CO2 saturated NGB. However, due to high concentration of Ca2+, a new carbonate CaCO3 dense layer was formed, increased the corrosion resistance of steel surface. T2 - EUROCORR 2022 CY - Berlin, Germany DA - 28.08.2022 KW - Corrosion KW - Geothermal KW - CO2 KW - Mortar PY - 2022 AN - OPUS4-55621 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Le, Quynh Hoa A1 - Bäßler, Ralph A1 - Bettge, Dirk T1 - Electrochemical behaviors of casing steel/mortar interface in CO2 saturated aquifer fluid N2 - To reveal the corrosion resistance of casing steel/mortar interface in CO2 injection condition, sandwich samples were prepared and exposed up to 20 weeks in aquifer fluid under 10 MPa and 60 °C. Cross section analysis revealed the crevice corrosion as main mechanism instead of pitting corrosion, which would be expected to happen in the extremely high Chloride concentration. Detailed analysis using EDS line scan shown the slow diffusion of Chloride, suggesting why pitting did not happen after 20 weeks. To mimic the passivated steel surface, the steel coupon was passivated in simulated pore solution having pH 13.5 for 42 days. The passivated coupon was further exposed to NGB solution for 28 days. Electrochemical characterization was performed along the exposure processes to reveal the change in impedance, indicating the corrosion resistance of steel casing/mortar interface. T2 - EUROCORR 2022 CY - Berlin, Germany DA - 28.08.2022 KW - Corrosion KW - CO2 quality KW - Pipeline network KW - CCS PY - 2022 SP - 859 EP - 865 PB - European Federation of Corrosion AN - OPUS4-55622 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Fürst, Richard T1 - European test standard for intumescent coatings applied to steel tension bars with solid section N2 - Description of the FIRESTEMIC project and the newly developed test standard for reactive fire protection systems on steel tension members. T2 - Symposium 2022 Heißbemessung - Structural Fire Engineering CY - Brunswick, Germany DA - 13.09.2022 KW - Fire tests KW - Tension member KW - Intumescent coating KW - Steel KW - Test standard PY - 2022 AN - OPUS4-55702 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Fürst, Richard A1 - Häßler, Dustin A1 - Peter, A. A1 - Rohleder, R. A1 - Hothan, Sascha T1 - European test standard intumescent coatings applied to steel tension bars with solid section N2 - Intumescent coatings are used in civil engineering to improve the fire resistance of steel constructions. Due to the thin coating thickness and the profile-following application, the architectural appearance of the steel structure can be preserved. EN 13381-8 provides regulations to determine the contribution to the fire resistance of intumescent coatings applied to steel beams and columns. The scope of this standard excludes tension members and steel members with solid sections. For products that have already been successfully tested and assessed on beams and columns, EN 13381-10 offers the possibility based on unloaded fire tests to extend the scope of application of intumescent coatings to tension bars with solid sections. This approach contradicts the national safety level in Germany, where mechanically loaded testing is mandatory. Therefore, a new part of the test standard series EN 13381 is currently developed to enable the application of intumescent coatings on steel tension bars with solid section based on mechanically loaded fire tests. BAM has already carried out numerous fire tests on loaded steel tension members with intumescent coatings. Currently, in the BAM research project FIRESTEMIC, the influence of the steel bar orientation and the profile type on the thermal performance of intumescent coatings are investigated. Both questions concerning the thermal protection ability of intumescent coatings were analysed based on three different test sets, which were carried out in the tension furnace (Fig. 1a). The fire exposure corresponds to the standard temperature-time curve according to EN 1363-1. This paper summarises the main findings from the fire tests conducted in the FIRESTEMIC project. The results serve as an experimental background for the proposal of the new standard. Regarding the bar orientation, a new test setup was developed and proposed for the new standard. The two tested commercial water-based intumescent coatings with applied dry film thickness from 1.5 mm to 2.5 mm showed only a slight dependence on the bar orientation. In terms of the steel profile type, circular and rectangular solid sections with identical section factor and applied dry film thickness were tested. It was observed that the circular solid bars with diameter 30 mm heat up faster compared to the solid rectangular bars with dimension 30×30 mm (Fig. 1b). Also at larger steel bars, i.e. diameter 40 mm and dimension 40×40 mm, the same trend occurred. Thus, it is recommended for the new test standard to allow a transfer of the test results from circular to rectangular solid sections. In addition, the paper will describe and explain the test and assessment procedure proposed for the newly developed standard. T2 - 8th Symposium Structural Fire Engineering CY - Brunswick, Germany DA - 13.09.2022 KW - Fire test KW - Steel KW - Tension member KW - Intumescent coating KW - Test standard PY - 2022 SP - 1 EP - 14 PB - TU Braunschweig CY - Braunschweig AN - OPUS4-55703 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Fürst, Richard A1 - Häßler, Dustin A1 - Hothan, Sascha T1 - Brandversuch eines Stahlzuggliedes mit reaktivem Brandschutzsystem N2 - Das Poster stellt den im Rahmen des Workshops "Feuerwiderstand von Stahlzuggliedern mit reaktiver Brandschutzbeschichtung" durchgeführten Brandversuch vor. T2 - Workshop - Feuerwiderstand von Stahlzuggliedern mit reaktiver Brandschutzbeschichtung CY - Berlin, Germany DA - 06.09.2022 KW - Brandschutz KW - Brandversuch KW - Feuerwiderstand KW - Reaktives Brandschutzsystem PY - 2022 AN - OPUS4-55699 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Fürst, Richard T1 - Research Project FIRESTEMIC - Results and Recommendations N2 - The presentation summarizes the results of the research project. T2 - Workshop 2022 - Feuerwiderstand von Stahlzuggliedern mit reaktiver Brandschutzbeschichtung CY - Berlin, Germany DA - 06.09.2022 KW - Fire tests KW - Intumescent coating KW - Steel KW - Tension member PY - 2022 AN - OPUS4-55700 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Häßler, Dustin A1 - Hothan, Sascha T1 - Neue Prüfnorm für reaktive Brandschutzsysteme auf Stahlzuggliedern N2 - Der Vortrag stellt den Entwurf der neuentwickelten Prüfnorm vor. T2 - Workshop 2022 - Feuerwiderstand von Stahlzuggliedern mit reaktiver Brandschutzbeschichtung CY - Berlin, Germany DA - 06.09.2022 KW - Feuerwiderstand KW - Brandschutz KW - Stahlzugglieder KW - Reaktives Brandschutzsystem KW - Prüfnorm PY - 2022 AN - OPUS4-55701 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schneider, Ronald T1 - Überwachung von Brücken mit digitalen Methoden N2 - Brücken werden durch Inspektionen und teilweise durch Monitoring überwacht, um Daten und Informationen über den Zustand und die Einwirkungen zu sammeln. Auf deren Grundlage werden Entscheidungen hinsichtlich Maßnahmen zur Gewährleistung der Sicherheit und Verfügbarkeit getroffen. In diesem Vortrag werden die Potentiale der Digitalisierung zur Unterstützung und Verbesserung der Brückenüberwachung diskutiert. Insbesondere werden die Bereiche Datenmanagement, Brückenmodellierung und Entscheidungsfindung betrachtet. T2 - BVPI Arbeitstagung 2022 CY - Berlin, Germany DA - 16.09.2022 KW - Entscheidungsfindung KW - Brücken KW - Überwachung KW - Digitalisierung KW - Datenmanagement KW - Modellierung PY - 2022 AN - OPUS4-55770 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Babutzka, Martin T1 - Vorstellung des Konzeptes und der Ziele des Arbeitskreises „Atmosphärische Korrosion“ N2 - Der Vortrag wurde im Rahmen der konstituierenden Sitzung des Arbeitskreises "Atmosphärische Korrosion" der GfKORR - Gesellschaft für Korrosionsschutz e.V. gehalten. Er stellt die zur Diskussion stehenden Fragestellungen und Herausforderungen im Bereich der atmosphärischen Korrosion zusammen, denen sich der neue Arbeitskreis widmen wird. T2 - Konstituierende Sitzung des GfKORR-Arbeitskreises „Atmosphärische Korrosion“ CY - Frankfurt a. M., Germany DA - 19.09.2022 KW - Atmosphärische Korrosion KW - Korrosion KW - Korrosionsschutz PY - 2022 AN - OPUS4-55772 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - THES A1 - Viefhues, Eva T1 - Subspace-based damage detection in engineering structures considering reference uncertainties and temperature effects N2 - Automated vibration-based damage detection is of increasing interest for structural health monitoring of engineering structures. In this context, stochastic subspace-based damage detection (SSDD) compares measurements from a testing state to a data-driven reference model in a statistical framework. In this thesis theoretical developments have been proposed to improve the robustness of SSDD for realistic applications conditions. First, a statistical test has been proposed considering the statistical uncertainties about the model obtained from the reference data. This leads to a precise description of the test’s distribution properties and damage detection thresholds. Second, an approach has been developed to account for environmental effects in SSDD. Based on reference measurements at few different environmental conditions, a test is derived with respect to an adequate interpolated reference. The proposed methods are validated in numerical simulations and applied to experimental data from the laboratory and outdoor structures. KW - Damage detection KW - Subspace methods KW - Vibrations KW - Uncertainty quantification KW - Environmental effects KW - Civil structures PY - 2021 SP - 1 EP - 191 CY - Universite de Rennes AN - OPUS4-55774 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kotula, Stefan T1 - Zinkbeizen nach alter ISO 8407 N2 - Der Vortrag beschäftigt sich mit der Problemstellung der Entfernung von Korrosionsprodukten auf Zinkoberflächen zur Bewertung des Masseverlustes. Er diskutiert die Diskrepanzen zwischen der alten Version der ISO 8407 und der aktuellen Version. T2 - Sitzung des DIN-Gemeinschaftsarbeitskreises NA 062 01 77 01 GAK CY - Online Meeting DA - 22.09.2022 KW - Atmosphärische Korrosion KW - Deckschichtbildung KW - ISO 8407 KW - Korrosion PY - 2022 AN - OPUS4-55807 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Savidis, S. A1 - Bergmann, M. A1 - Schepers, Winfried A1 - Fontara, I.-K. T1 - Wave propagation in inhomogeneous media via FE/PML method N2 - The Perfectly Matched Layer (PML) method is an efficient approach to imposing radiation conditions at the bounded region of interest in case of wave propagation in unbounded domains. This paper presents and validates 3D FE/PML numerical schemes based on two different PML formulations for homogeneous and inhomogeneous geological media exhibiting discrete or continuous inhomogeneity. In the equation of motion for the PML domain the applied stretching behavior is expressed either as complex material properties or as complex coordinates. Both PML formulations are implemented in the FEM and verified against analytical solutions. Three different types of material inhomogeneity are considered: layered half-space, continuously inhomogeneous half-space with linear velocity profile and continuously inhomogeneous half-space with nonlinear velocity profile. Sensitivity analyses are conducted, and the performance of the developed numerical schemes is investigated taking into account a broad variation of the PML parameters. Recommendations are given for the optimal values of the PML parameters for the case of homogeneous and inhomogeneous geological media. KW - Perfectly Matched Layer (PML) KW - Unbounded domain KW - Finite elements KW - Continuously inhomogeneous geological media PY - 2022 DO - https://doi.org/10.1002/gete.202100028 VL - 45 IS - 2 SP - 98 EP - 107 PB - Ernst & Sohn CY - Berlin AN - OPUS4-54969 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Balscheit, Hagen T1 - Buckling Behavior of embedded Shells N2 - Presentation on ongoing test campaign on buckling of embedded piles, which is part of the VERBATIM-Project. T2 - Phd Seminar LFU-Innsbruck CY - Innsbruck, Austria DA - 24.06.2022 KW - Buckling KW - Monopiles KW - Windenergy KW - Foundations KW - Offshore PY - 2022 AN - OPUS4-55458 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bender, R. A1 - Féron, D. A1 - Mills, D. A1 - Ritter, S. A1 - Bäßler, Ralph A1 - Bettge, Dirk A1 - de Graeve, I. A1 - Dugstad, A. A1 - Grassini, S. A1 - Hack, T. A1 - Halama, M. A1 - Han, E.-H. A1 - Harder, T. A1 - Hinds, G. A1 - Kittel, J. A1 - Krieg, R. A1 - Leygraf, C. A1 - Martinelli, L. A1 - Mol, A. A1 - Neff, D. A1 - Nilsson, J.-O. A1 - Odnevall, I. A1 - Paterson, S. A1 - Paul, S. A1 - Prošek, T. A1 - Raupach, M. A1 - Revilla, R. I. A1 - Ropital, F. A1 - Schweigart, H. A1 - Szala, E. A1 - Terryn, H. A1 - Tidblad, J. A1 - Virtanen, S. A1 - Volovitch, P. A1 - Watkinson, D. A1 - Wilms, M. A1 - Winning, G. A1 - Zheludkevich, M. T1 - Corrosion challenges towards a sustainable society N2 - A global transition towards more sustainable, affordable and reliable energy systems is being stimulated by the Paris Agreement and the United Nation's 2030 Agenda for Sustainable Development. This poses a challenge for the corrosion industry, as building climate‐resilient energy systems and infrastructures brings with it a long‐term direction, so as a result the long‐term behaviour of structural materials (mainly metals and alloys) becomes a major prospect. With this in mind “Corrosion Challenges Towards a Sustainable Society” presents a series of cases showing the importance of corrosion protection of metals and alloys in the development of energy production to further understand the science of corrosion, and bring the need for research and the consequences of corrosion into public and political focus. This includes emphasis on the limitation of greenhouse gas emissions, on the lifetime of infrastructures, implants, cultural heritage artefacts, and a variety of other topics. KW - Corrosion KW - Corrosion costs KW - Corrosion protection KW - Preventive strategies PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-554801 DO - https://doi.org/10.1002/maco.202213140 SN - 1521-4176 VL - 73 IS - 11 SP - 1730 EP - 1751 PB - Wiley-VCH CY - Weinheim AN - OPUS4-55480 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schepers, Winfried A1 - Kulke, D. T1 - Ermittlung dynamischer Bodensteifigkeit aus konventionellen geotechnischen Berichten N2 - Am Beispiel von mehreren Bauvorhaben wird untersucht, mit welchen Unsicherheiten bei der Anwendung von Korrelationen zwischen Sondierergebnissen und Scherwellengeschwindigkeit zur Beschreibung der dynamischen Bodeneigenschaften gerechnet werden muss. Die Auswertung von Korrelationen aus der Literatur zur Abschätzung der Scherwellengeschwindigkeit aus Drucksondierdaten zeigt, dass bei homogenen Sandböden die Verteilung der Scherwellengeschwindigkeit über die Tiefe sehr gut wiedergegeben werden kann. Die Korrelationen haben dabei die Tendenz, den tatsächlichen Wert zu überschätzen. In den vorliegenden Fällen haben sich Überschätzungen zwischen 20 % und 50 % ergeben. Mit zunehmendem Feinkornanteil werden die Unsicherheiten aus den Korrelationen jedoch größer. T2 - 7. VDI-Fachtagung Baudynamik CY - Würzburg, Germany DA - 27.04.2022 KW - Dynamische Bodensteifigkeit PY - 2022 SN - 978-3-18-092379-6 SN - 0083-5560 VL - 2379 SP - 347 EP - 359 PB - VDI-Verlag CY - Düsseldorf AN - OPUS4-54762 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz T1 - Wellenausbreitung und Pfähle im inhomogenen Boden – Gesetzmäßigkeiten für die Gründung von Windenergieanlagen und für die Prognose von Bahnerschütterungen aus Tunneln N2 - Es wird eine gekoppelte Finite-Element-Randelementmethode zur Berechnung von Pfahlgrün-dungen in inhomogenen (geschichteten) Böden vorgestellt. Sie beruht auf den Greenschen Funktionen (Punktlastlösungen) für inhomogene Böden. Diese Lösungen können auch für die Wellenausbreitung in der Tiefe, zum Beispiel von einem Bahntunnel zu einem eingebetteten Gebäude, dem Kellergeschoss benutzt werden. Die Punktlastlösungen in der Tiefe werden mit der Halbraumlösung an der Bodenoberfläche und mit der Vollraumlösung verglichen und Gesetzmäßigkeiten für geschichtete Böden abgeleitet. Zu den Pfahlgründungen werden die Horizontalnachgiebigkeiten von Pfählen in geschichteten Böden dargestellt. Für den homogenen und den kontinuierlich steifer werdenden Boden werden Potenzgesetze für den Boden- und Pfahleinfluss aufgestellt. Der Vergleich mit dem Winkler-Modell der rein lokalen Bodenreaktion zeigt, dass die Winkler-Bettung in allen Fällen einen zu kleinen Bodeneinfluss ergibt. T2 - 7. VDI-Fachtagung Baudynamik CY - Würzburg, Germany DA - 27.04.2022 KW - Wellenausbreitung in der Tiefe KW - Nachgiebigkeiten KW - Windenergieanlagen PY - 2022 SN - 978-1-18-092379-6 SN - 0083-5560 VL - 2379 SP - 697 EP - 706 PB - VDI-Verlag CY - Düsseldorf AN - OPUS4-54768 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz T1 - Wellenausbreitung und Pfähle im inhomogenen Boden – Gesetzmäßigkeiten für die Gründung von Windenergieanlagen und für die Prognose von Bahnerschütterungen aus Tunneln N2 - Es wird eine gekoppelte Finite-Element-Randelementmethode zur Berechnung von Pfahlgrün-dungen in inhomogenen (geschichteten) Böden vorgestellt. Sie beruht auf den Greenschen Funktionen (Punktlastlösungen) für inhomogene Böden. Diese Lösungen können auch für die Wellenausbreitung in der Tiefe, zum Beispiel von einem Bahntunnel zu einem eingebetteten Gebäude, dem Kellergeschoss benutzt werden. Die Punktlastlösungen in der Tiefe werden mit der Halbraumlösung an der Bodenoberfläche und mit der Vollraumlösung verglichen und Gesetzmäßigkeiten für geschichtete Böden abgeleitet. Zu den Pfahlgründungen werden die Horizontalnachgiebigkeiten von Pfählen in geschichteten Böden dargestellt. Für den homoge-nen und den kontinuierlich steifer werdenden Boden werden Potenzgesetze für den Boden- und Pfahleinfluss aufgestellt. Der Vergleich mit dem Winkler-Modell der rein lokalen Boden-reaktion zeigt, dass die Winkler-Bettung in allen Fällen einen zu kleinen Bodeneinfluss ergibt. T2 - 7. VDI-Fachtagung Baudynamik CY - Würzburg, Germany DA - 27.4.2022 KW - Wellenausbreitung in der Tiefe KW - Pfahlnachgiebigkeiten KW - Erschütterungen KW - Tunnel PY - 2022 AN - OPUS4-54769 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Fürst, Richard A1 - Hejtmanek, P. A1 - Vlach, T. A1 - Repka, J. A1 - Mozer, V. A1 - Hajek, P. T1 - Experimental Evaluation of Carbon Reinforced TRC with Cement Suspension Matrix at Elevated Temperature N2 - Textile-reinforced concrete (TRC) is a new composite material comprising high-performance concrete and textile reinforcement from textile yarns with a matrix, usually consisting of epoxy resins (ER). The most significant advantage of ER is the homogenization of all filaments in the yarn and full utilization of its tensile potential. Nevertheless, ER matrix is a critical part of TRC design from the perspective of the fire resistance due to its relatively low resistance at temperatures of approximately 120 C. This work expands the previously performed mechanical tests at normal temperatures with cement suspension (CS) as a non-combustible material for the yarn matrix. Here, the mechanical properties of CS matrix at elevated temperatures were verified. It was found that the addition of polypropylene fibers into HPC negatively affected the mechanical results of CS matrix specimens. Simultaneously, thermal insulation effect of the covering layers with different thicknesses did not significantly influence the residual bending strength of specimens with CS matrix and achieved similar results as reference specimens. Furthermore, all specimens with ER matrix progressively collapsed. Finally, CS as a textile reinforcement of yarn matrix appears to be a suitable solution for increasing the temperature resistance of TRC structures and for substituting synthetic resins. KW - Cement matrix KW - Cement suspension KW - Carbon fibers KW - Textile reinforced concrete KW - High-performance concrete KW - Elevated temperature KW - Fire safety KW - Fire resistance PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-550766 DO - https://doi.org/10.3390/polym14112174 SN - 2073-4360 VL - 14 IS - 11 SP - 1 EP - 16 PB - MDPI CY - Basel, Switzerland AN - OPUS4-55076 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Vogler, Nico A1 - Lehmann, Jens A1 - Bohlmann, Tatjana A1 - Kronemann, Jens T1 - Gel-bound Colourants as a Substitute for the Sprayed Application of pH-Indicator Solution N2 - In general, pH-sensitive colorants such as phenolphthalein are applied on freshly split surfaces of building structures to determine the state of carbonation. For years, it has been known that the aerosols of phenolphthalein are suspected of being carcinogenic. Hence, more work has currently being done on alternative indicators for the use in research and the use on construction sites. Over the past years, mainly pH indicators from other research areas and natural dyes were investigated for their usability to cementitious systems. This paper presents the experimental results of using phenolphthalein solution bound in agar-agar gel. This gel-bound indicator allows the future use of the already known phenolphthalein dye without the health hazards for the user. To demonstrate the flexibility of the gel-bound colorant, different application forms of the indicator were carried out and assessed. In addition, the results obtained by the different methods were statistically evaluated to ensure validity. The accuracy of the results was confirmed by thermogravimetric analysis and IR spectroscopic studies as reference methods. It has also succeeded to demonstrate the comparability of the results achieved by the gel-bound colorant with the results of the common sprayed application method. As an additional gain in knowledge, comparative results of indicator tests, TGA analysis, and FTIR investigation are shown. KW - Concrete Carbonation KW - Gel-bound Colorants KW - pH Indicator KW - Thermal Gravimetric Analysis KW - FTIR-ATR Measurements PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-551493 UR - http://www.sciencepublishinggroup.com/j/ajce DO - https://doi.org/10.11648/j.ajce.20221003.16 SN - 2330-8729 SN - 2330-8737 VL - 10 IS - 3 SP - 135 EP - 144 PB - Science Publishing Group CY - New York, NY AN - OPUS4-55149 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schlick-Hasper, Eva T1 - Flow properties of powdery or granular filling substances of dangerous goods packagings - Comparison of the measurement of the angle of repose and the determination of the Hausner ratio N2 - To ensure safety when transporting dangerous goods, it is important to specify the flow properties of the respective solid filling substance of the packagings. For this purpose, the angle of repose is currently used for the UN approvals in Germany. Measurements were carried out on 12 powdery or granular substances applying the angle of repose measuring methods customary in the test centres. The results of the methods differ significantly from each other. In addition, some of the techniques cannot be applied for very cohesive or coarse-grained materials. The results for the angle of repose show a strong scatter for some constellations (coefficient of variation more than 20 %). Safety during transport of dangerous goods cannot be guaranteed with this currently practiced system of measuring the angle of repose. As a consequence, an alternative parameter to characterize the flow properties of bulk materials should be used in the recognized test centers for dangerous goods packagings, such as the Hausner ratio. This approach leads to more precise test results for the substances examined (maximum coefficient of variation 2.8 %). It also has advantages in terms of applicability and occupational safety. Since the flow properties are safety-relevant, both in terms of mechanical safety and safety against the release of dangerous substances, the testing practice in the recognized test labs should be improved and standardized. T2 - IAPRI Bangkok 2022 23rd World Packaging Conference CY - Online meeting DA - 12.06.2022 KW - Sift-proofness KW - Powders KW - Flow properties KW - Flowability KW - Angle of repose KW - Hausner ratio PY - 2022 AN - OPUS4-55103 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CHAP A1 - Hothan, Sascha A1 - Häßler, Dustin ED - Kuhlmann, U. T1 - Reaktive Brandschutzsysteme N2 - Die Erkenntnisse zu reaktiven Brandschutzsystemen (RBS) werden kontinuierlich erweitert, was sich in der Entwicklung neuer Produkte und der Ausweitung des durch technische Regelungen abgedeckten Anwendungsbereichs äußert. Der vorliegende Beitrag konzentriert sich auf die Verwendung von RBS auf Stahlkonstruktionen. Neben einer umfassenden Darstellung der aktuellen nationalen und europäischen Regelungen zu RBS, werden technologische Besonderheiten und deren Einfluss auf den Regelungsinhalt im Beitrag thematisiert. Dabei werden neben sich abzeichnenden Neuerungen auch die entsprechenden wissenschaftlich-technologischen Grundlagen dargelegt. Ferner wird die Frage nach der Bewertung der Dauerhaftigkeit von RBS für deutlich über 10 Jahre hinausgehende Zeiträume, und den sich damit einstellenden Feuerwiderstand der Konstruktion behandelt. Der Beitrag schließt mit einer Darstellung zur aktuellen Forschung. Daraus abgeleitet wird ein Ausblick auf zukünftige Forschungsthemen. KW - Reaktives Brandschutzsystem KW - Stahl KW - Brandschutz KW - Feuerwiderstand PY - 2022 SN - 978-3-433-03361-6 SP - 367 EP - 400 PB - Ernst & Sohn Verlag CY - Berlin AN - OPUS4-54735 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Burkert, Andreas T1 - Korrosion metallener Werkstoffe-Grundlagen N2 - Im Vortrag werden die wesentlichen Grundlagen zum Verständnis der Korrosion metallener Werkstoffe in komprimierter Form vorgestellt. Der Schwerpunkt liegt auf der Betrachtung der atmosphärischen Korrosion und den sich daraus ergebenden Anforderungen an den Korrosionsschutz. T2 - CORPAC Seminar: Wie lassen sich VCI-Korrosionsschutz und Nachhaltigkeit vereinbaren? CY - Weidhausen b. Coburg, Germany DA - 30.03.2022 KW - Einflussgrößen KW - Atmosphärische Korrosion KW - Befeuchtungsdauer PY - 2022 AN - OPUS4-54594 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Erning, Johann Wilhelm T1 - Hygienic assessment of SLM-printed stainless steel N2 - Elektrochemische Messungen zur hygienischen Bewertung additiv gefertigter Bauteile werden diskutiert. Die Bewertung und Details des Werkstoffs werden beschrieben, Anwendungsbeispiele gezeigt. T2 - Kormat 2022 CY - Online meeting DA - 26.04.2022 KW - Korrosion KW - Trinkwasser KW - Hygienische Bewertung KW - Additive Fertigung PY - 2022 AN - OPUS4-54709 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Erning, Johann Wilhelm T1 - Materials in contact with drinking water and regulatory issues N2 - The state of play in regard to regulations of materials in contact with drinking water in europe is discussed T2 - Kormat 2022 CY - Online meeting DA - 26.04.2022 KW - Korrosion KW - Trinkwasser KW - Hygiene KW - Risikobewertung PY - 2022 AN - OPUS4-54710 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Erning, Johann Wilhelm T1 - Hygienische Eigenschaften von additiv gefertigtem 1.4404 in Trinkwasser N2 - Elektrochemische Messungen zur hygienischen Bewertung additiv gefertigter Bauteile werden diskutiert. Die Bewertung und Details des Werkstoffs werden beschrieben, Anwendungsbeispiele gezeigt. T2 - 3. Fachtagung Werkstoffe und Additive Fertigung CY - Dresden, Germany DA - 11.05.2022 KW - Korrosion KW - Trinkwasser KW - Hygiene KW - Additive Fertigung PY - 2022 AN - OPUS4-54829 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Burkert, Andreas A1 - Lehmann, Jens T1 - Einfach und echt schnell - Der KorroPad Test N2 - In diesem dritten Teil wird die KorroPad Prüfmethode vorgestellt und erläutert. T2 - ISER Kursleiterfortbildung 2022 CY - Düsseldorf, Germany DA - 26.09.2022 KW - Korrosion KW - nichtrostender Stahl KW - KorroPad KW - Korrosionsprüfung KW - Schnelltest PY - 2022 AN - OPUS4-55858 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schartel, Bernhard T1 - Flame retardancy features sustainability: Fake fiction, food for thought, or future N2 - • Renewable sources find their way into flame retardancy • Innovative solutions meet sustainability • Facing recycling and circular economy T2 - AMI Fire Retardants in Plastics CY - Philadelphia, PA, US DA - 26.04.2023 KW - Flame retardants KW - Sustainability KW - Resources from waste streams KW - Biocomposite KW - Vitrimers PY - 2023 AN - OPUS4-57415 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Balscheit, Hagen T1 - Nichtlineares Tragverhalten stahlbaulicher Offshore-Strukturen unter spezieller Berücksichtigung der Bauwerk-Boden-Interaktion N2 - Der Vortrag gibt einen Überblick über die ingenieurmäßige Handhabung der stahlbaulichen Bemessung von großen Monopiles für Offshorewindenergieanlagen. Besonderer Focus liegt dabei auf jenen Phänomenen, welche durch eine starke Interaktion zwischen Stahlstruktur und Boden gekennzeichnet werden. T2 - Ringvorlesung: Praxisreihe Stahlbau CY - Innsbruck, Austria DA - 09.05.2023 KW - Pile Tip Buckling KW - Shell Buckling KW - Soil Struture Interaction PY - 2023 AN - OPUS4-57521 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Tschirschwitz, Rico A1 - Bernardy, Christopher A1 - Wagner, Patrick A1 - Rappsilber, Tim A1 - Liebner, Christian A1 - Hahn, S.-K. A1 - Krause, U. T1 - Harmful effects of lithium-ion battery thermal runaway: scale-up tests from cell to second-life modules N2 - For a comprehensive safety assessment of stationary lithium-ion-battery applications, it is necessary to better understand the consequences of thermal runaway (TR). In this study, experimental tests comprising twelve TR experiments including four single-cell tests, two cell stack tests and six second-life module tests (2.65 kW h and 6.85 kW h) with an NMC-cathode under similar initial conditions were conducted. The temperature (direct at cells/modules and in near field), mass loss, cell/module voltage, and qualitative vent gas composition (Fourier transform infrared (FTIR) and diode laser spectroscopy (DLS) for HF) were measured. The results of the tests showed that the battery TR is accompanied by severe and in some cases violent chemical reactions. In most cases, TR was not accompanied by pregassing of the modules. Jet flames up to a length of 5 m and fragment throwing to distances to more than 30 m were detected. The TR of the tested modules was accompanied by significant mass loss of up to 82%. The maximum HF concentration measured was 76 ppm, whereby the measured HF concentrations in the module tests were not necessarily higher than that in the cell stack tests. Subsequently, an explosion of the released vent gas occurred in one of the tests, resulting in the intensification of the negative consequences. According to the evaluation of the gas measurements with regard to toxicity base on the “Acute Exposure Guideline Levels” (AEGL), there is some concern with regards to CO, which may be equally as important to consider as the release of HF. KW - Large-scale tests KW - Lithium-ion battery KW - Gas emission KW - Thermal runaway KW - Consequences PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-579054 DO - https://doi.org/10.1039/D3RA02881J SN - 2046-2069 VL - 13 IS - 30 SP - 20761 EP - 20779 PB - Royal Society of Chemistry (RSC) CY - Cambridge, UK AN - OPUS4-57905 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bäßler, Ralph A1 - Bettge, Dirk A1 - Bender, R. A1 - Féron, D. A1 - Mills, D. A1 - Ritter, S. A1 - de Graeve, I. A1 - Dugstad, A. A1 - Grassini, S. A1 - Hack, T. A1 - Halama, M. A1 - Han, E.-H. A1 - Harder, T. A1 - Hinds, G. A1 - Kittel, J. A1 - Krieg, R. A1 - Leygraf, C. A1 - Martinelli, L. A1 - Mol, A. A1 - Neff, D. A1 - Nilsson, J.-O. A1 - Odnevall, I. A1 - Paterson, S. A1 - Paul, S. A1 - Prosek, T. A1 - Raupach, M. A1 - Revilla, R. I. A1 - Ropital, F. A1 - Schweigart, H. A1 - Szala, E. A1 - Therryn, H. A1 - Tidblad, J. A1 - Virtanen, S. A1 - Volovitch, P. A1 - Watkinson, D. A1 - Wilms, M. A1 - Winning, G. A1 - Zheludkevich, M. T1 - La corrosion: un défi pour une société durable N2 - Une transition mondiale vers des systèmes énergétiques plus durables, abordables et fiables a été initiée par l’accord de Paris et l’Agenda 2030 des Nations unies pour un développement durable. Il s’agit là d’un défi industriel majeur car les systèmes et infrastructures énergétiques résilients au changement climatique exigent de se positionner pour le long terme. Se pencher sur le comportement dans la durée des matériaux structurels - principalement des métaux et des alliages - s’impose alors comme une nécessité. Dans cette optique, « La corrosion : un défi pour une société durable »présente une série de cas montrant l’importance de la tenue à la corrosion et de la protection anticorrosion des métaux et des alliages pour le développement de systèmes durables, économiques et fiables de production d’énergie. KW - Corrosion KW - Coûts de la corrosion KW - Protection KW - Anticorrosion KW - Stratégies deprévention PY - 2023 DO - https://doi.org/10.51257/a-v1-cor2000 SN - 2555-5383 VL - 2023 IS - Avril SP - 1 EP - 23 CY - Saint-Denis, France AN - OPUS4-57927 LA - fra AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kapoor, M. A1 - Sørensen, J. D. A1 - Ghosh, S. A1 - Thöns, Sebastian T1 - Decision theoretic approach for identification of optimal proof load with sparse resistance information N2 - Proof load testing may be performed to confirm the reliability of the bridge for an existing classification or to prove the reliability for a higher classification. In this paper, a probabilistic decision analysis approach is applied to the scenario for the evaluation of target proof load in the situation where information on the bridge resistance model is lacking. In this case, the resistance model is established by proof loading and taking very basic prior knowledge into account. The decision scenario is modelled in the context of the proof load test planner who shall choose the required load level for assessment of a bridge. The choice of the load level depends on the risks due to the testing and the expected benefit gain from the test. Information acquired about the loading response from monitoring during the proof load testing is modelled by taking basis in the model uncertainty formulation. The optimal proof load level for classification of a single lane, simply supported bridge of 8m span subjected to live load from very heavy (gross weight > 80 tons) transport vehicles was calculated. The optimal proof load level was identified as leading to a positive expected benefit gain to the decision maker while also satisfying target reliability criteria for remaining service life. The analysis was performed for the evaluation of bridge performance with respect to five classifications of very heavy transport vehicles with different vehicle weights and configurations. T2 - 10th International Conference on Bridge Maintenance, Safety and Management (IABMAS) CY - Sapporo, Japan DA - 11.04.2021 KW - Proof load testing KW - Probabilistic decision analysis KW - Bridge resistance model PY - 2021 SN - 978-0-429-27911-9 DO - https://doi.org/10.1201/9780429279119-104 SP - 789 EP - 797 PB - CRC Press CY - Boca Raton, Florida AN - OPUS4-57879 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Tabaka, Weronika T1 - Bench-scale fire stability testing of carbon fibre reinforced polymer laminates with protective layers N2 - Fire resistance testing of components made of carbon fibre reinforced polymers (CFRP) composites usually demands intermediate-scale or full-scale testing. In this study, a bench-scale test is presented as a practicable and efficient method to assess the improvement in structural integrity of CFRP with different protective interlayers during fire. Fire stability is one of the biggest issues of carbon fibre reinforced polymer (CFRP) composites, particularly when they are using in load bearing applications. As soon as the glass transition temperature of polymer matrix (100-200°C) is achieved, the composite loses its structural integrity, what leads to the distortion and failure. The principal fire stability test is based on simultaneous application of fire and mechanical load. Since the carbon fibres can transfer the tensile loads quite well, the compression load is chosen as a required mechanical load for a test. The fire tests were preceded by a static load test at room temperature to determine ultimate failure load. The specimen was loaded with a compression force until the failure load was reached, which was observed as a buckling. For the fire tests, 10% of compression failure load and direct flame of a fully developed fire (heat flux ≈ 180 kW m-2) were applied simultaneously to the specimen, while the time to failure was measured. The possibilities of bench-scale fire stability testing were presented by investigating new types of laminate structures, which exhibit promising flame retardancy and fireproof properties. The new approach of CFRP laminate differs with a protective concept. Every system consists of two different interlayers (titanium foil, thermoplastic foil PEI, ceramic layer WHIPOX, rubber tape Pyrostat, basalt fibres and kenaf fibres), where the one layer constitutes the fireproof protection, that delays the rise of temperature in the rest of laminate, and the second layer provides very good structural connection with carbon fibre layers, thus improves the mechanical integrity of CFRP composite in fire. The time to failure of CFRP composite was 17s. Protective systems significantly enhance the fire stability and increased time to failure by 3 to 10 times. Thicker specimens showed longer resistance time, however CFRP laminate with ceramic layer and titanium foil presented outstanding results and the best performance. The protection with Kenaf and basalt fibres offered a natural fibre solution with also good fire resistance performance Although bench-scale tests are limited with respect to assessing the performance of components and structures, they are valuable in the assessment of different materials concepts. Furthermore, the reduced effort of conducting bench-scale test (lower costs, time, personnel resources) makes it more practical and effective. T2 - 19th European meeting on Fire Retardant Polymeric Materials (FRPM23) CY - Dübendorf, Switzerland DA - 26.06.2023 KW - Fire resistance KW - Carbon fibre reinforced polymer KW - Bench-scale testing PY - 2023 AN - OPUS4-57880 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Goller, Sebastian M. T1 - How reactions between smoke suppressants in flame retardant PA6.6 change the burning behavior and smoke emission N2 - The interactions between polymer, flame retardant and smoke suppressant are presented. Moreover, it is discussed, how the molecular changes affect the fire behavior and the smoke emission. T2 - 19th European meeting on Fire Retardant Polymeric Materials (FRPM23) CY - Dübendorf, Switzerland DA - 26.06.2023 KW - Smoke KW - Polyamide KW - Flame retardancy KW - Smoke suppressant KW - Fire behavior PY - 2023 AN - OPUS4-57845 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Jauregui Rozo, Maria T1 - Transfer of the modes of action from polymer materials to glass-fiber-reinforced plastics: flame retardancy – fire resistance – post-fire mechanics N2 - Fire resistance of fiber-reinforced polymers (FRPs) has been an important area of research for many years since FRPs are mainly used in the transportation and construction sectors. This study presents the fire behavior, and mechanical performance between the flame retarded pure epoxy resin and flame retarded glass-fiber composites before, during, and after a fire event. This enables a deeper understanding of the transferability of flame retardants on composite materials. T2 - 19th European Meeting on Fire Retardant Polymeric Materials (FRPM23) CY - Dübendorf, Switzerland DA - 26.06.2023 KW - Glass-fiber Reinforced Polymer KW - Flame Retardancy KW - Fire Behavior KW - Flammability KW - Modes of Action PY - 2023 AN - OPUS4-57846 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Tiebe, Carlo A1 - Zunkel, Astrid A1 - Klein, Ulrich A1 - Schlischka, Jörg A1 - Klinger, Christian T1 - Materialuntersuchungen an einem explodierten Umlaufkühler N2 - Ein Umlaufkühler ist im Betrieb explodiert. Splitter des zerborstenen Gehäuses aus Kunststoff wurden mit dem Kühlwasser in die Umgebung geschleudert, am Betriebsort entstand Personenschaden. Bei Funktionsprüfungen am beschädigten Gerät traten unerwartet - aber reproduzierbar - Knalleffekte bei Berührung der Außenoberfläche der Kupfer-Kühlschlange auf. Ein möglicher Mechanismus konnte im Labor durch Synthese von Kupferazid auf Kupferproben und Auslösung vergleichbarer Knalleffekte nachgestellt werden. Damit ist die Plausibilität des beschriebenen Schadensereignisses mit diesem oder einem ähnlich reagierenden Stoff belegt. Ein eindeutiger Nachweis darüber, dass bei dem aufgetretenen Schadensfall dieselbe chemische Reaktion stattgefunden hat, war nicht möglich, da die Belag-Überreste aus dem explodierten Kühlgerät für eine Analyse nicht mehr in ausreichender Menge verfügbar gewesen sind. KW - Kupferazid KW - Umlaufkühler KW - Explosion KW - Gutachten KW - Schadensanalyse KW - Materialuntersuchung PY - 2022 SN - 2191-0073 VL - 12 IS - 7/8 SP - 15 EP - 21 PB - VDI Fachmedien CY - Düsseldorf AN - OPUS4-55570 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Matos, P. R. de A1 - Andrade Neto, J. S. A1 - Durlo Tambara, Luis Urbano A1 - Rodríguez, E. D. A1 - Kirchheim, A. P. A1 - Campos, C. E. M. de T1 - Measuring the early-age volumetric change of cement paste through in-situ XRD N2 - Volumetric changes follow Portland cement hydration reactions: aluminates' hydration is generally expansive, whereas silicates' reaction leads to shrinkage. Determining the volumetric variation at very early ages (i.e., first minutes/hours) presents operational challenges; most standards prescribe the measurement on specimens that are already hardened, while measurements from the fresh state are not standardized. This article reports the first attempt to use in-situ X-ray diffraction (XRD) to measure the early-age volumetric variation of a cementitious paste. For this purpose, a C3A + gypsum paste was assessed for 36 h, measuring its vertical displacement over time through XRD. The results showed that the expansion increased in the first ∼13 h, in line with the ettringite formed up to ∼11 h. In addition, the volumetric expansion agreed well with the heat release in calorimetry. It is concluded that the volumetric variation measurement of cementitious pastes through in-situ XRD is a promising technique, but further studies are needed to make this technique consolidated. KW - X-ray diffraction KW - Shrinkage KW - Expansion KW - Hydration KW - Portland cement PY - 2023 DO - https://doi.org/10.1016/j.mtcomm.2023.106857 SN - 2352-4928 VL - 36 SP - 1 EP - 4 PB - Elsevier Ltd. CY - Amsterdam AN - OPUS4-58107 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Liehr, A. A1 - Wegener, T. A1 - Degener, Sebastian A1 - Bolender, A. A1 - Möller, N. A1 - Niendorf, T. T1 - Experimental Analysis of the Stability of Retained Austenite in a Low‐Alloy 42CrSi Steel after Different Quenching and Partitioning Heat Treatments N2 - Quenching and partitioning (Q&P) steels are characterized by an excellent combination of strength and ductility, opening up great potentials for advanced lightweight components. The Q&P treatment results in microstructures with a martensitic matrix being responsible for increased strength whereas interstitially enriched metastable retained austenite (RA) contributes to excellent ductility. Herein, a comprehensive experimental characterization of microstructure evolution and austenite stability is carried out on a 42CrSi steel being subjected to different Q&P treatments. The microstructure of both conditions is characterized by scanning electron microscopy as well as X‐ray diffraction (XRD) phase analysis. Besides macroscopic standard tensile tests, RA evolution under tensile loading is investigated by in situ XRD using synchrotron and laboratory methods. As a result of different quenching temperatures, the two conditions considered are characterized by different RA contents and morphologies, resulting in different strain hardening behaviors as well as strength and ductility values under tensile loading. In situ synchrotron measurements show differences in the transformation kinetics being rationalized by the different morphologies of the RA. Eventually, the evolution of the phase specific stresses can be explained by the well‐known Masing model. KW - Condensed Matter Physics KW - General Materials Science PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-581618 DO - https://doi.org/10.1002/adem.202300380 SN - 1438-1656 VL - 25 IS - 17 SP - 1 EP - 16 PB - Wiley AN - OPUS4-58161 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Jauregui Rozo, Maria T1 - Transfer of the Flame Retardancy and Post-Fire Mechanics from Polymer Materials to Glass-Fiber-Reinforced Plastics N2 - This study presents the processability, fire behavior, and mechanical performance between the flame retarded pure epoxy resin and flame retarded glass-fiber-reinforced plastic before, during, and after a fire event. This enables a deeper understanding of the transferability of flame retardants, modes of action, char enhancement, and flame inhibition on composite materials T2 - Twenty-third international conference on composite materials (ICCM23) CY - Belfast, United Kingdom DA - 31.07.2023 KW - Glass-Fiber Reinforced Polymer KW - Flame Retardancy KW - Mechanical Testing KW - Epoxy Resin KW - Modes of Action PY - 2023 AN - OPUS4-58086 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Erning, Johann Wilhelm T1 - "Grabenkorrosion": From A historic scientific debate to the solution, still modern failures N2 - Grooving corrosion occured in the 1970ies. It returned in the 1990ies, causing a scientific debate leading to a solution. This solution got lost, so new failures appear. The route of the discussion to the solution is described, old and new failures are discussed. T2 - Eurocorr 2023 CY - Brussels, Belgium DA - 27.08.2023 KW - Grooving corrosion KW - Drinking water installations KW - Steel pipes PY - 2023 AN - OPUS4-58186 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Erning, Johann Wilhelm T1 - Desinfektion: Risiken in der Trinkwasser-Installation N2 - Die Präsentation beschreibt die Vorgehensweise bei einer ggf. erforderlichen esinfektionsmaßnahme. Es werden verschiedene Möglichkeiten erörtert und Vor- und Nachteile bschrieben. Im zweiten teil wird die Philosophie der Risiskovermeidung in der Trinkwasserinstallation beschrieben. T2 - Seminar für öffentlich bestellt und vereidigte Sachverständige, SHK Bayern CY - Nuremberg, Germany DA - 28.03.2023 KW - Korrosion KW - Desinfektion KW - Trinkwasserinstallation KW - Risikobewertung PY - 2023 AN - OPUS4-58187 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Tabaka, Weronika T1 - Bench-scale fire stability testing - Protective layers in carbon fibre reinforced polymer laminates N2 - Fire resistance testing of components made of carbon fibre reinforced polymers (CFRP) composites usually demands intermediate-scale or full-scale testing. In this study, a bench-scale test is presented as a practicable and efficient method to assess the improvement in structural integrity of CFRP with different protective interlayers during fire. T2 - International Conference on Composite Materials (ICCM23) CY - Belfast, UK DA - 30.07.2023 KW - Fire resistance KW - Bench-scale testing KW - Carbon fibre reinforced polymer composite PY - 2023 AN - OPUS4-58099 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schneider, Ronald T1 - Von der Datenerfassung bis zur Entscheidungsfindung: Jede Brücken-Überwachung bedarf einer Gesamtmethodik N2 - Brücken müssen laufend überwacht werden, damit die Unsicherheiten hinsichtlich ihres Zustands, ihrer Beanspruchung und ihrer Leistungsfähigkeit verringert werden können. Diese Aufgabe soll künftig mit digitalen Methoden erleichtert werden. Im folgenden Beitrag werden deshalb die digitale Bauwerksmodellierung und die Entscheidungsfindung beleuchtet. Dazu wird gezeigt, wie Zustandsdiagnosen und -prognosen digital ermöglicht werden und wie durch diagnostische und prognostische Modelle eine wissenschaftliche Basis für risikobasierte Entscheidungen über Erhaltungsmaßnahmen und für den Übergang vom reaktiven zum vorausschauenden Brückenmanagement gebildet werden kann. Dabei wird klar: Jede Brücken-Überwachung bedarf einer Gesamtmethodik, ihre wichtigsten Elemente sind: Datenerfassung, Datenmanagement, Datenanalyse, Bauwerksmodellierung, Bauwerksbewertung und die letztendlichen Entscheidungen über notwendige Erhaltungsmaßnahmen. KW - Prädiktive Instandhaltung KW - Brücken KW - Erhaltungsmanagement KW - Digitale Zwillinge PY - 2023 IS - 62 SP - 76 EP - 83 AN - OPUS4-57811 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz T1 - Wave propagation from hammer, vibrator and railway excitation – theoretical and measured attenuation in space and frequency domain N2 - The attenuation of wave amplitudes is ruled by the planar, cylindrical or spherical geometry of the wave front (the geometric or power-law attenuation) but also by the damping of the soil (an exponential attenuation). Several low- and high-frequency filter effects are derived for the layering and the damping of the soil, for the moving static and the distributed train loads and for a homogeneous or randomly heterogeneous soil. Measurements of hammer- and train-induced vibrations at five sites have been analysed for these attenuation and filter effects. The measured attenuation with distance can be discribed by generalised power laws and some reasons will be discussed. The theoretical filter effects can well be found in the measurements. T2 - Wave Mechanics and Vibrations Conference CY - Lisbon, Potugal DA - 04.07.2022 KW - Hammer impact KW - Train passage KW - Layered soil KW - Attenuation KW - Filter effects KW - Randomly heterogeneous soil KW - Scattering PY - 2023 SN - 978-3-031-15757-8 DO - https://doi.org/10.1007/978-3-031-15758-5_35 SP - 352 EP - 359 PB - Springer Nature CY - Cham, Schweiz AN - OPUS4-56034 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz T1 - Measurement and evaluation tools for ground and building vibrations from industrial process-es, construction work, traffic and other sources N2 - Vibration measurements have many causes and many technical and natural sources. Problems can sometimes be solved by short-term measurements, but in many cases, a long-term measurement is necessary. In long-term measurements of days, weeks, months and even years, it is easy to collect a huge quantity of raw data, but at the end, the post-processing of these data can be exhausting (for example one-year vibration data of a wind energy tower). A software has been developed which con-sists of measuring and evaluation routines where the measuring routines can operate different meas-uring systems and different measuring cards. The main advantage of this software is the fact that the interesting evaluations can be integrated in the measuring process so that the characteristics of the vibration can be extracted without storing all the raw data. Only important time segments are stored, for example train passages. The overall concept of the software and the main evaluation routines will be described in some details. Examples of our measurement experience will illustrate the capabilities of the software. 1) Surveying construction work in nearby sensitive buildings (for example an old wind tunnel), including a stable alarm system and meaningful vibration limits. 2) Prediction of train-induced vibration for a planned building to prevent annoyance and to improve the building design. 3) Modal analysis and long term measurements of several single- or multi-span, concrete or steel bridges 4) Modal and wave analysis of coupled floors in a historical building (“Neues Palais” at Potsdam). 5) Soil properties of various measurement sites (different routines to evaluate the dispersion). Moreover, from many projects, amplitudes, frequencies, and attenuation laws have been collected and analysed for the different sources such as vibratory or impact pile driving and ground compaction, demolition work with different machines, blasting in quarries and in tunnel works, bomb and mine clearing. T2 - 28th International Congress on Sound and Vibration (ICSV28) CY - Online meeting DA - 25.07.2022 KW - Ground vibration KW - Building vibration KW - Measurement KW - Evaluation KW - Modes and waves PY - 2022 AN - OPUS4-56035 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz T1 - Effects of a varying track and soil stiffness on ground vibrations near railway lines N2 - Usually, geometric irregularities are considered as the main cause of ground vibrations from trains. A varying stiffness of the track, the track support and the soil can also generate ground vibrations. The regular stiffness variation of the track on and between the sleepers results in a deterministic dynamic axle load. The random stiffness variation of the track support yields also dynamic axle loads. The dynamic axle loads are generated by the varying wheel displacements under the static axle load by the acceleration of the unsprung mass of the rail vehicle. The random stiffness variation has a second effect. The pulses from the passage of the static axle loads are superposed regularly to the quasi-static response, but also irregularly to yield a “scattered” part of the axle pulses. The same holds for a random variation of the soil stiffness. All these effects of stiffness variations have been calculated by wavenumber-domain multi-beam track models, a random finite-element soil model and the superposition of axle impulses in a stochastic simulation. The results are confronted with many measurements at different sites. It is concluded that the stiffness variation of the track and the soil generate an important ground vibration component near railway lines. T2 - Railways 2022 CY - Montpellier, France DA - 22.08.2022 KW - Ground vibration KW - Railways KW - Varying track stiffness KW - Varying soil stiffness PY - 2022 AN - OPUS4-56036 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz T1 - Railway-induced ground and building vibrations – Analysis in frequency-wavenumber domain and fast prediction with approximate models N2 - A simple and fast prediction scheme is presented for train-induced ground and building vibrations. For the emission, finite-element boundary-element or multiple-beam-on-continuous-soil models of the track have been analysed and approximated by faster track-on-Winkler-soil models. The vehicle-track interaction due to irregularities yields the excitation forces. For the transmission of waves in the soil, the wavenumber integral of the compliance of layered soils has been evaluated. The calculation time is reduced for the prediction by using the solution of a homogeneous half-space with a frequency-dependent wave velocity (the dispersion) of the soil. For the immision, many 2 and 3-dimenisonal finite-element building models have been investigated, and a good approximation has been established by a 1-dimensional soil-wall-floor model. In addition, the axle sequence of the train, the quasi-static and the “scattered” response of the soil, and the wave propagation from a tunnel to a pile foundation of a building have been included. T2 - ISMA-Conference CY - Leuven, Belgium DA - 12.09.2022 KW - Ground vibration KW - Building vibration KW - Railways KW - Simple and fast prediction PY - 2022 AN - OPUS4-56038 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Lenz, J. U. A1 - Pospiech, D. A1 - Komber, H. A1 - Korwitz, A. A1 - Kobsch, O. A1 - Paven, M. A1 - Albach, R. W. A1 - Günther, Martin A1 - Schartel, Bernhard T1 - Effective halogen-free flame-retardant additives for crosslinked rigid polyisocyanurate foams: Comparison of chemical structures N2 - The impact of phosphorus-containing flame retardants (FR) on rigid polyisocyanurate (PIR) foams is studied by systematic variation of the chemical structure of the FR, including non-NCO-reactive and NCO-reactive dibenzo[d,f][1,3,2]dioxaphosphepine 6-oxide (BPPO)- and 9,10 dihydro-9-oxa-10 phosphaphenanthrene-10-oxide (DOPO)-containing compounds, among them a number of compounds not reported so far. These PIR foams are compared with PIR foams without FR and with standard FRs with respect to foam properties, thermal decomposition, and fire behavior. Although BPPO and DOPO differ by just one oxygen atom, the impact on the FR properties is very significant: when the FR is a filler or a dangling (dead) end in the PIR polymer network, DOPO is more effective than BPPO. When the FR is a subunit of a diol and it is fully incorporated in the PIR network, BPPO delivers superior results. KW - Flame retardant; KW - Dibenzo[d,f][1,3,2]dioxaphosphepine 6-oxide; BPPO KW - 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide; DOPO KW - Polyisocyanurate; PIR KW - Rigid foam KW - Cone calorimeter KW - Pudovik reaction PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-567712 DO - https://doi.org/10.3390/ma16010172 SN - 1996-1944 VL - 16 IS - 1 SP - 1 EP - 22 PB - MDPI CY - Basel AN - OPUS4-56771 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Brinkmann, M. A1 - Wiehle, Philipp T1 - Correlation between relative humidity and the strength and deformation characteristics of unstabilised earth masonry N2 - The mechanical properties of unstabilised earthen building materials are distinctively influenced by changes in material moisture content. However, this moisture-dependency often remains unconsidered in the calculation of the load-bearing capacity of earth constructions. This paper aims to derive a convenient way to sufficiently consider the impact of different material moisture contents on the mechanical properties of unstabilised earth masonry. Therefore, the influence of relative humidity and temperature on the strength and deformation characteristics of unstabilised earth blocks, earth mortar and earth masonry is evaluated by conducting compression tests under various climate conditions. The results show that the compressive strength and the modulus of elasticity are linearly correlated with the relative humidity, whereas changes in temperature at constant relative humidity have no significant influence. To account the distinct moisture-dependency, a general applicable modification factor for unstabilised earthen materials is provided, which enables the adjustment of the compressive strength and the modulus of elasticity in dependency of arbitrary hygroscopic material moisture contents. KW - Earth masonry KW - Earth blocks KW - Relative humidity KW - Modulus of elasticity KW - Moisture KW - Compressive strength KW - Stress–strain-relation PY - 2023 DO - https://doi.org/10.1016/j.conbuildmat.2022.130048 SN - 0950-0618 VL - 366 IS - 22 SP - 1 EP - 11 PB - Elsevier BV AN - OPUS4-56732 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz T1 - Challenges of vibration prediction – realistic irregularities, the scattering of axle pulses, and the tunnel-surface reduction N2 - A prediction software has been developed by BAM. The following topics have still be solved. A realistic irregularity spectrum can be derived from axle-box measurements. It agrees wel with the spectrum used for the high-speed 2 project in the United Kingdom. In addition, the scattering of axle pulses should be included. This mid-frequency component can also be found in the HS2 procedure. Finally, the reduction in case of a tunnel line compared to a surface line should be included. Some measurement results of BAM, HS2 and other institutes show a certain mid-frequency reduction. This is due to the load distribution of the tunnel which yields softer axle pulses and the scattered axle impulses are reduced. T2 - ISO/TC 108/SC 2/WG 8 Working group Ground-borne noise and vibration from rail systems CY - London, UK DA - 21.11.2022 KW - Ground vibration KW - Railway trafiic KW - Prediction KW - Irregularities KW - Axle pulses KW - Tunnel line KW - Surface line PY - 2022 AN - OPUS4-56738 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Haacke, Nasrin A1 - Paton, E. T1 - Impact-based classification of extreme rainfall events using a simplified overland flow model N2 - In this study, we present a new rainfall classification method based on the potential of individual rainstorm events to generate and sustain overland flow on a simplified urban model surface. Conventional rainfall classification approaches using peak intensities or rainfall sums can lead to mis-judgements of the impact of rainfall events, as they do not explicitly consider the potential of rain to generate and sustain substantial amounts of overland flow on typical sealed urban surfaces. The new method of impact-based rainfall classification proposed here comprises three steps: Identification of rainfall events from high-resolution time series, computation of overland flow depths for each event, and impact-based classification of rainfall events as a function of the magnitude of overland flow. The accuracy of this approach was evaluated by its ability to describe seasonal and annual occurrences of and variations in rainstorm impacts for high-resolution series at three different urban stations in Germany. KW - Flow depth KW - Impact assessment KW - Overland flow KW - Urban flooding KW - Rainfall classification PY - 2023 DO - https://doi.org/10.1080/1573062X.2022.2164731 SP - 1 EP - 11 PB - Taylor & Francis Group CY - London AN - OPUS4-56794 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Durlo Tambara, Luis Urbano A1 - Lima, G. T. S. A1 - Silvestro, L. A1 - Ruviaro, A. S. A1 - Gleize, P. J. P. A1 - de Azevedo, A. R. G. T1 - Influence of polycarboxylate superplasticizer and calcium sulfoaluminate cement on the rheology, hydration kinetics, and porosity of Portland cement pastes N2 - Binary systems composed of Portland cement (PC) and calcium sulfoaluminate (CSA) cement have stood out for applications requiring high early strengths. Nevertheless, the application of these systems may be limited due to their properties in the fresh state, which requires a better understanding of the rheological behavior of these materials. Thus, this study evaluated the incorporation of different polycarboxylate-based superplasticizer (SP) contents (0.15, 0.20, and 0.25 wt%) on PC and PC-CSA binary cement pastes. Rotational rheometry, isothermal calorimetry, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and nitrogen adsorption and desorption tests to assess the pore size distribution of cement pastes were conducted. While the SP incorporation reduced the dynamic yield stress of PC pastes, it progressively increased the yield stress of PC-CSA systems. The increase in SP content increased the main heat flow peak of PC-CSA pastes, although it did not significantly affect the cumulative heat after 160 h of hydration. FTIR and XRD confirm higher ettringite contents in the binary systems and indicate the presence of carboaluminates phases after 7 d of hydration in both PC and PC-CSA and hemicarboaluminate in PC-CSA pastes. The CSA incorporation reduced the cumulative pore volume by up to 32% compared to PC pastes, while the SP content evaluated did not significantly affect the porosity of PC-CSA pastes. KW - Calcium sulfoaluminate cement KW - Portland cement KW - Superplasticizer KW - Rheology KW - Hydration PY - 2023 DO - https://doi.org/10.1016/j.jobe.2023.106120 SN - 2352-7102 VL - 68 SP - 1 EP - 15 PB - Elsevier Ltd. CY - Amsterdam AN - OPUS4-57034 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - da Silva, T. R. A1 - Matos, P. R. de A1 - Durlo Tambara, Luis Urbano A1 - Marvila, M. T. A1 - de Azevedo, A. R. G. T1 - A review on the performance of açaí fiber in cementitious composites: Characteristics and application challenges N2 - This paper aimed to perform an exploratory literature review, focusing on the aspects of hydration and rheological properties of cementitious composites with açaí fibers. The use of natural fibers as a reinforcement in cementitious matrices has been widely studied, and açaí fiber is a promising option due to its unique characteristics. However, there is still a lack of knowledge regarding the correlation between fiber parameters and the technological properties of composites, which limits the development of new applications, such as 3D printing. The review provided an overview of the main characteristics of açaí fibers and the parameters for their application in cementitious matrices. Alkali treatment with 5% NaOH solution for 1 h shows increased mechanical and physical properties in açaí fibers. Despite the potential advantages of these composites, they pose challenges due to the different fiber surface treatment and interfacial transitions and the processing conditions of the fibers. Although small addition of açaí fibers slightly decreases the cement hydration process, keeping the cross-compatibility index high (>95). To overcome these challenges, it is necessary to evaluate the rheological behavior of cementitious materials with açaí fibers, which has not been reported in the literature. By doing so, it will be possible to optimize the processing conditions and develop new applications, such as additive manufacturing, which has never been explored with açaí fibers. KW - Natural fibers KW - Açaí fiber KW - Portland cement KW - Alternative materials PY - 2023 DO - https://doi.org/10.1016/j.jobe.2023.106481 SN - 2352-7102 VL - 71 IS - 106481 SP - 1 EP - 21 PB - Elsevier Ltd. CY - Amsterdam AN - OPUS4-57326 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Voigt, Sascha A1 - Sträubig, Felix A1 - Kwade, A. A1 - Zehfuß, J. A1 - Knaust, Christian T1 - An empirical model for lithium-ion battery fires for CFD applications N2 - Lithium-ion batteries are a key technology to achieve the goals of limiting climate change due to the important role as traction technology for Electric Vehicles and in stationary energy storage systems. Over(dis) charge, mechanical damage due to accidents or thermal abuse such as fires can initiate an accelerated self-heating process of the batteries, called thermal runaway. A thermal runaway can propagate from cell to cell within a larger assembly of cells such as modules or battery packs and can cause rapid heat and toxic gas emissions. The resulting battery fire can spread to adjacent facilities, e.g. other cars in underground car parks or to a whole building in case of a large stationary energy storage. For proof of fire protection requirements or to design suitable fire protection systems, Computational Fluid Dynamic (CFD) simulations are getting more and more important. The aim of CFD fire simulations is to predict the global hazards of a fire to its surroundings, that is mainly characterized by the release of heat and smoke and its spread in the fire environment. There are many numerical investigations of lithium-ion batteries in the literature. One class of models is used to simulate the charge and discharge process of lithium-ion batteries and to predict the temperature or voltage evolution inside the battery. On the other hand, there are models describing batteries under abuse conditions to predict the consequences of a thermal runaway event to the local environment, like the temperatures inside a battery or at the battery surface. Henriksen et al. use a generic battery gas mixture to simulate an explosion of vented gases from a Lithium Iron Phosphate battery and compare experimental results for the explosion pressure and the position of the flame front to the outcomes of a simulation with Xifoam. Larsson et al. used a combination of CFD simulations with FDS and thermal model with COMSOL to predict the temperature development of neighboring cells in a thermal runaway propagation. Truchot et al. use a design Heat Release Rate (HRR) curve for a battery based on experimental measurements to build up an overall HRR curve for a truck loaded with 100 lithium-ion batteries. This summed up HRR and corresponding smoke production curve is then used as an input for a simulation of a truck fire in a tunnel with Fire Dynamics Simulator (FDS). The pre-definition of the HRR curve is a frequently used method in fire engineering. It has the disadvantage, that the heat release cannot be influenced by physical processes, such as changed ventilation conditions or extinguishing measures. In this paper, a model is presented that determines the release of heat and gases based on the thermal runaway mechanisms of the battery, which can be used in CFD fire simulations with focus on prediction of fire hazards to nearby environment. KW - Lithium-ion battery KW - Battery fires KW - Computational Fluid Dynamic (CFD) KW - Empirical model PY - 2023 DO - https://doi.org/10.1016/j.firesaf.2022.103725 SN - 0379-7112 VL - 135 IS - 135 SP - 1 EP - 12 PB - Elsevier Ltd. AN - OPUS4-57347 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Durlo Tambara, Luis Urbano T1 - Influence of dredging mud on the calcium sulfoaluminate cement hydration N2 - Dredging sediment refers to materials removed from the bottom of a water body during dredging operations. Mainly the dreading mud contains clay, silt, sand, water, and alkalis. This work incorporated dredging mud into the calcium sulfoaluminate cement at replacement levels of 0%, 10%, 30%, and 50% by weight. Pastes were evaluated after 1d, 28d, and 90d- hydration through mechanical strengths and the reaction rate by isothermal conduction calorimetry. XRD and MIP characterized the reaction products. The findings showed that small replacements (10% and 30%) increased early strength with higher ettringite formation in the system at 1d of curing. However, the evolution of mechanical strength was lower than the reference (0% replacement) over time. The results showed that in low replacement dosages, the dredging mud act as a nucleation site for the hydration of calcium sulfoaluminate phases. T2 - 7th International Conference Non-Traditional Cement & Concrete (NTCC) CY - Brno, Czech Republic DA - 25.06.2023 KW - Calcium sulfoaluminate cement KW - Dredging mud KW - Hydration KW - Paste PY - 2023 AN - OPUS4-58054 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schneider, Ronald T1 - Structural integrity management research at BAM N2 - This presentation provides an overview on the structural integrity management research at BAM. In addition, a framework for monitoring and risk-informed inspection and maintenance planning for offshore steel structures is presented. T2 - Structural Health Monitoring Using Statistical Pattern Recognition CY - Berlin, Germany DA - 20.03.2023 KW - Structural integrity KW - Monitoring KW - Maintenance KW - Inspeciton KW - Bridges KW - Offshore wind PY - 2023 AN - OPUS4-57864 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Amano, K. O. A. A1 - Hahn, S.-K. A1 - Butt, N. A1 - Vorwerk, P. A1 - Gimadieva, E. A1 - Tschirschwitz, Rico A1 - Rappsilber, Tim A1 - Krause, U. T1 - Composition and Explosibility of Gas Emissions from Lithium-Ion Batteries Undergoing Thermal Runaway N2 - Lithium-based batteries have the potential to undergo thermal runaway (TR), during which mixtures of gases are released. The purpose of this study was to assess the explosibility of the gaseous emission from LIBs of an NMC-based cathode during thermal runaway. In the current project, a series of pouch lithium-based battery cells was exposed to abuse conditions (thermal) to study the total amount of gases released and the composition of the gas mixture. First, the battery cells were placed in a closed vessel, and the pressure and temperature rise inside the vessel were measured. In a second step, the composition of gases was analysed using a Fourier transform Infrared (FTIR) spectrometer. We found that the amount of released gases was up to 102 ± 4 L, with a clear dependence on the battery capacity. This study showed that the concentration of gaseous emissions such as carbon monoxide (CO), methane (CH4), ethylene (C2H4), ethane (C2H6), and hydrogen cyanide (HCN) increased with higher cell capacity. Of the five studied flammable gases, the maximum concentrations of carbon monoxide (16.85 vol%), methane (7.6 vol%), and ethylene (7.86 vol%) were identified to be within their explosible range. Applying Le Chatelier’s law, a calculated lower explosion limit (LEL) of 7% in volume fraction was obtained for the gas mixture. The upper explosion limit (UEL) of the gas mixture was also found to be 31% in volume. A filter comprising pyrobubbles was used for the removal of the studied gas components released during the thermal abuse. The investigation revealed that the pyrobubbles filter was highly effect in the removal of HCN (up to 94% removal) and CO2 (up to 100% removal). Herein, we report the dependency of the method of thermal runaway trigger on the measured maximum temperature. KW - Lithium-ion battery KW - Thermal runaway KW - Smoke gas emission KW - Gas explosion KW - Explosion limit PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-576477 DO - https://doi.org/10.3390/batteries9060300 VL - 9 IS - 6 SP - 1 EP - 19 PB - MDPI CY - Basel, Switzerland AN - OPUS4-57647 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Balscheit, Hagen T1 - Offshore Gründungen - Nichtlineare Effekte bei der stahlbaulichen Auslegung großer Pfahlgründungen für Offshore Windenergieanlagen N2 - Dieser Kurzvortragg erläutert nichtlineare Phänomene die angesichts der aktuell wachsenden Dimensionen von Monopfahlgründungen für Offshorewindenergieanlagen zunehmend an Bedeutung gewinnen. Insbesondere wird dabei auf das Pfahlfußbeulen sowie das Schalenbeulen des bereits installierten Pfahles eingegangen. T2 - 27. Brandburgischer Bauingeniertag BBIT2023 CY - Cottbus, Germany DA - 09.06.2023 KW - Beulen KW - Pfahlfußbeulen KW - Stabilität KW - Monopile KW - Windenergie PY - 2023 AN - OPUS4-57653 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Schilling, Markus T1 - Full-Notch Creep Test Ontology (ontoFNCT) N2 - This is the stable version of the full-notch creep test ontology (OntoFNCT) that ontologically represents the full-notch creep test. OntoFNCT has been developed in accordance with the corresponding test standard ISO 16770:2019-09 Plastics - Determination of environmental stress cracking (ESC) of polyethylene - Full-notch creep test (FNCT). The OntoFNCT provides conceptualizations that are supposed to be valid for the description of full-notch creep tests and associated data in accordance with the corresponding test standard. By using OntoFNCT for storing full-notch creep test data, all data will be well structured and based on a common vocabulary agreed on by an expert group (generation of FAIR data) which is meant to lead to enhanced data interoperability. This comprises several data categories such as primary data, secondary data and metadata. Data will be human and machine readable. The usage of OntoFNCT facilitates data retrieval and downstream usage. Due to a close connection to the mid-level PMD core ontology (PMDco), the interoperability of full-notch creep test data is enhanced and querying in combination with other aspects and data within the broad field of materials science and engineering (MSE) is facilitated. The class structure of OntoFNCT forms a comprehensible and semantic layer for unified storage of data generated in a full-notch creep test including the possibility to record data from analysis and re-evaluation. Furthermore, extensive metadata allows to assess data quality and reliability. Following the open world assumption, object properties are deliberately low restrictive and sparse. KW - Ontology KW - Full-Notch Creep Test KW - FNCT KW - Knowledge Representation KW - Semantic Web Technologies KW - Data Structures KW - Data Management PY - 2024 UR - https://github.com/MarkusSchilling/ontoFNCT/blob/4abce82852190a5e444d302da077aa7404f433f0/ontoFNCT.ttl UR - https://raw.githubusercontent.com/MarkusSchilling/ontoFNCT/main/ontoFNCT.ttl PB - GitHub CY - San Francisco, CA, USA AN - OPUS4-59815 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Turski Silva Diniz, Analice A1 - Schartel, Bernhard T1 - The effects of property variation on the dripping behaviour of polymers during UL94 test simulated by particle finite element method N2 - The dripping behaviour of polymers is often observed experimentally through the UL94 flammability standard test. In this work, polymeric dripping under fire is investigated numerically using particle finite element method. A parametric analysis was carried out to observe the influence of a single property on overall dripping behaviour via a UL94 vertical test model. Surrogates and property ranges were defined for variation of the following parameters: glass transition temperature (Tg), melting temperature (Tm), decomposition temperature (Td), density (ρ), specific heat capacity (Cp), apparent effective heat of combustion of the volatiles, char yield (μ), thermal conductivity (k), and viscosity (η). Polyamide, poly(ether ether ketone), poly(methyl methacrylate), and polysulfone were used as benchmarks. Simulated results showed that specific heat capacity, thermal conductivity, and char yield allied with viscosity were the properties that most influenced dripping behaviour (starting time and occurrence). KW - Dripping KW - PFEM KW - UL 94 KW - Simulation KW - Fire behaviour PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-597449 DO - https://doi.org/10.1515/epoly-2023-0194 SN - 1618-7229 VL - 24 IS - 1 PB - De Gruyter AN - OPUS4-59744 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Friedrich, Christian T1 - Eignungsprüfungen geophysikalischer Sensoren zur Rissdetektion an Demonstrationsbauwerken N2 - Bei der Betonage von Abdichtbauwerken können Temperaturen bis 110 °C und hohe Drücke bis 5 MPa erreicht werden. Mittels Technikumsversuchen wurde nachgewiesen, dass Mikroakustik- und Ultraschallsensoren zum Einbau in Demonstrationsbauwerke geeignet sind. Die Untersuchungen wurden bei der BAM (Bundesanstalt für Materialforschung und -prüfung) in Berlin durchgeführt. Es ist vorgesehen, die Sensoren in Morsleben am Demonstrationsbauwerk im Anhydrit einzusetzen. T2 - 84. Jahrestagung der Deutschen Geophysikalischen Gesellschaft CY - Jena, Germany DA - 10.03.2024 KW - Ultraschall KW - Eignungsprüfung KW - Risse KW - Abdichtbauwerk KW - Anhydrit PY - 2024 AN - OPUS4-59772 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Goller, Sebastian M. T1 - Avoiding antimony – effect of Ca(H2PO2)2 on smoke emission and fire behaviour in brominated ABS N2 - The replacement of antimony trioxide (Sb2O3) in brominated flame-retardant ABS (ABS/FR) is of great interest. This study investigates the influence of calcium hypophosphite (CaP) in ABS/FR on flame retardancy and smoke emission. Different amounts of talc are added to ABS/FR/CaP to evaluate the influence of an inorganic barrier on smoke emission and flame retardancy. The cone calorimeter unveiled a reduction by 46% in PHRR for ABS/FR/CaP. Additional 8 wt.-% talc (ABS/FR/CaP/8Talc) reduced the PHRR by 61%. ABS/FR/CaP exhibited a more condensed phase action, which resulted in less smoke emission. The study investigates the influence of CaP in ABS/FR on the smoke toxicity, smoke density and the smoke particles distribution in the smoke density chamber (ISO 5659-2) coupled to a FTIR spectrometer and electrical low pressure cascade impactor (ELPI). T2 - 5th Asia-Oceania Symposium on Fire Safety Materials Science and Engineering CY - Sydney, Australia DA - 26.08.2023 KW - Smoke KW - ABS KW - Calcium hypophosphite KW - Antimony KW - Brominated flame retardant KW - Fire scenario KW - Burning behavior PY - 2023 AN - OPUS4-58232 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Lesny, K. A1 - Arnold, P. A1 - Sorgatz, J. A1 - Schneider, Ronald T1 - Wie sicher sind unsere Bauwerke? - Strukturpapier des Arbeitskreises 2.15 der DGGT „Zuverlässigkeitsbasierte Methoden in der Geotechnik“ N2 - Der zukünftige Eurocode 7 wird ausdrücklich die Nutzung zuverlässigkeitsbasierter Methoden in der geotechnischen Planung und Bemessung erlauben. In Deutschland gibt es bisher kaum Erfahrung in der praktischen Anwendung derartiger Verfahren und entsprechend sind die Vorbehalte gegenüber diesen Methoden oft groß. Der neue DGGT-Arbeitskreis (AK) 2.15 „Zuverlässigkeitsbasierte Methoden in der Geotechnik“ hat sich zum Ziel gesetzt, durch praxisorientierte Anleitungen und Empfehlungen sowie begleitende Aus- und Weiterbildungsangebote den praktischen Zugang zu diesen Verfahren zu unterstützen. Ziel ist es, Möglichkeiten und Grenzen zu verdeutlichen sowie vor allem ihre Potenziale zu erschließen. In dem vorliegenden Beitrag werden allgemeine Grundlagen und die zukünftigen Arbeitsfelder des AK 2.15 vorgestellt. Ausgehend von der Einführung relevanter Fachbegriffe wird zunächst die Einbettung zuverlässigkeitsbasierter Verfahren in den aktuellen Normungs- und Regelungskontext aufgezeigt. Anschließend werden anhand des Lebenszyklus eines geotechnischen Bauwerks die Unsicherheiten in den geotechnischen Prognosen und Bewertungen beschrieben. Daran anknüpfend wird aufgezeigt, an welchen Stellen zuverlässigkeitsbasierte Methoden als mögliches Werkzeug sinnvoll genutzt werden können, um Ingenieur:innen, Bauherr:innen und Prüfer:innen in Nachweis- und Entscheidungsprozessen zu unterstützen. Zu den sich daraus ableitenden Arbeitsthemen werden durch den AK 2.15 zukünftig Empfehlungen erarbeitet und sukzessive veröffentlicht KW - Brückensicherheit KW - Sicherheit KW - Wahrscheinlichkeit KW - Zuverlässigkeit KW - Bemessung KW - Bewertung KW - Offshore Wind PY - 2023 DO - https://doi.org/10.1002/gete.202300014 VL - 46 IS - 3 SP - 153 EP - 164 PB - Ernst & Sohn GmbH CY - Berlin AN - OPUS4-58208 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Erning, Johann Wilhelm A1 - Bäcker, C. A1 - Mathys, W. A1 - Dresemann, O. T1 - Untersuchung der Schwermetallmigration in zirkulierenden Kaltwassersystemen N2 - Kaltwasserzirkulationssysteme haben sich in diversen Bereichen (Kliniken, Hotels, Schiffsbau usw.) etabliert. Die hydraulische Funktionsweise und das Berechnungsverfahren orientieren sich an der bewährten Warmwasser-Zirkulation, dennoch besteht für dieses „neue System“ eine gewisse Einführungsskepsis. Die elementare Anforderung der Trinkwasserverordnung (TrinkwV) besteht darin, dass „Trinkwasser […] so beschaffen sein [muss], dass durch Genuss oder Gebrauch eine Schädigung der menschlichen Gesundheit […] nicht zu besorgen ist.“ Diese Anforderung gilt als erfüllt, wenn mindestens die allgemein anerkannten Regeln der Technik (a.a.R.d.T.) bei Planung, Bau und Betrieb einer Trinkwasser-Installation eingehalten werden, das Trinkwasser den mikrobiologischen, chemischen, radiologischen Anforderungen der TrinkwV entspricht und es rein und genusstauglich ist. Da die Kaltwasserzirkulation aktuell noch dem Stand der Technik zuzuschreiben ist und die Einhaltung chemischer Anforderungen in Bezug auf erhöhte Schwermetallmigration in der Diskussion steht, wurden entsprechende chemische Parameter in Bestandsanlagen untersucht. Die Ergebnisse werden nachfolgend vorgestellt und sollen Betreibern, Fachplanern und ausführenden Fachunternehmen die Vorteile des Systems aufzeigen und Unsicherheiten ausräumen. KW - Kaltwasserzirkulation KW - Schwermetallabgabe KW - Trinkwasserinstallation KW - Korrosion PY - 2023 SN - 1436-686X VL - 2023 IS - 6 SP - 12 EP - 16 PB - HUSS-MEDIEN GmbH CY - Berlin AN - OPUS4-58189 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Colmenares, Daniel A1 - Costa, Giancarlo A1 - Civera, Marco A1 - Surace, Cecilia A1 - Karoumi, Raid T1 - Quantification of the human–structure interaction effect through full-scale dynamic testing: The Folke Bernadotte Bridge N2 - An analytical expression for the frequency response function of a coupled pedestrian-bridge system is presented and evaluated using an experimental measurement campaign performed on the Folke Bernadotte Bridge in Stockholm, Sweden. A finite element model and the modal models that consider the human–structure interaction effect are calibrated with respect to the measurements. The properties of the spring–mass–damper model representing the pedestrians were identified, considering the different structural modes of the system. Good agreement was obtained between the experimental and theoretical frequency response functions. A sensitivity analysis of the obtained solution was performed, validating the determined analytical expression for the frequency response function of the coupled pedestrian-bridge system that takes into account the human–structure interaction effect. KW - Safety KW - Building and Construction KW - Architecture KW - Civil and Structural Engineering KW - Risk KW - Reliability KW - Quality PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-584038 DO - https://doi.org/10.1016/j.istruc.2023.06.133 SN - 2352-0124 VL - 55 SP - 2249 EP - 2265 PB - Elsevier AN - OPUS4-58403 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sunder, S. T1 - Microstructure analysis and mechanical characterization of flame-retardant epoxy resins transferred to glass fiber composites via prepregs N2 - The transfer of flame-retardant epoxy resin formulations to composites for structural and lightweight applications in the energy and transport sector can be complex and requires systematic investigation. Here, uncoated and silane-coated ammonium polyphosphate (APP, Si-APP) intumescent compounds are transferred to prepregs using a Bisphenol A diglycidyl ether (DGEBA) resin matrix to 0/90o bidirectional glass fibers with an aerial weight of 600 g/m2. Inorganic silicates (InSi) are added to improve the fire residues of the composites after combustion and the total amount of flame retardants in the resin formulations was 10% by weight. The prepregs' fiber volume content (FVC) is corroborated using in-process measurements and thermogravimetric analysis. This was found to be approximately 60% for the composites containing APP, which is ideal for load-bearing applications with high mechanical strength. However, the Si-APP containing prepregs showed an inconsistent FVC potentially due to interactions with the commercial sizing of the glass fibers. The composites subsequently prepared are analysed for potential filtration effects of the additives via SEM after immobilization in a cured resin and platinum sputtering. The inter-laminar shear strength and the mechanical strength of the composites are compared via three-point bending tests. Additionally, the fire performance of the composites is analysed using cone calorimetry. It was found there was minimal impact of the loading of the flame retardants on the delamination of the composites and the flexural strength. However, the high density of the glass fibers possibly results in a suppression of the mode of action of the flame retardants in the composites. Therefore, the fire residues of the composites are further compared using SEM, and the flame-retardant modes of action upon transfer are investigated. T2 - FEMS EUROMAT 23 CY - Frankfurt am Main, Germany DA - 03.09.2023 KW - Lightweight construction KW - Flame retardancy KW - Composites PY - 2023 AN - OPUS4-59136 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sunder, S. T1 - Adapting intumescent/low-melting glass flame-retardant formulations for transfer to glass-fiber-reinforced composites and post-fire mechanical analysis N2 - The residual post-fire mechanical properties of fiber-reinforced epoxy composites are influenced by their fire residues after burning. This study uses intumescent/low-melting glass flame retardants to tailor fire residues in epoxy resin. Processibility of prepregs and their quality are analysed for transfer of the flame-retardant epoxy resins to layered glass-fiber reinforced composites. Minimal effects were found on the pre-fire flexural strengths of the composites due to low loading of the flame retardants. However, when transferred to glass-fiber reinforced composites, the fire residues diminish significantly. Further studies are required to improve theoretical and experimental estimations of the post-fire mechanics of the composites. T2 - SAMPE Europe Conference 2023 CY - Madrid, Spain DA - 03.10.2023 KW - Composites KW - Flame retardancy KW - Lightweight KW - Post fire mechanics KW - Intumescent PY - 2023 AN - OPUS4-59137 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sunder, S. A1 - Jauregui Rozo, Maria A1 - Schartel, Bernhard A1 - Ruckdäschel, H. T1 - Adapting intumescent/low-melting glass flame-retardant formulations for transfer to glass-fiber-reinforced composites and post-fire mechanical analysis N2 - The residual post-fire mechanical properties of fiber-reinforced epoxy composites are influenced by their fire residues after burning. This study uses intumescent/low-melting glass flame retardants to tailor fire residues in epoxy resin. Processibility of prepregs and their quality are analysed for transfer of the flame-retardant epoxy resins to layered glass-fiber reinforced composites. Minimal effects were found on the pre-fire flexural strengths of the composites due to low loading of the flame retardants. However, when transferred to glass-fiber reinforced composites, the fire residues diminish significantly. Further studies are required to improve theoretical and experimental estimations of the post-fire mechanics of the composites. T2 - SAMPE Europe Conference 2023 CY - Madrid, Spain DA - 03.10.2023 KW - Fire residue KW - Prepregs KW - Mechanics KW - Lightweight materials KW - Composites KW - Flame retardancy PY - 2023 SP - 1 EP - 7 AN - OPUS4-59138 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Tambara, R. F. A1 - Durlo Tambara, Luis Urbano A1 - Venquiaruto, S. D. A1 - Pereira da Costa, F. B. T1 - Evaluation of the mechanical performance and capillary absorption of concretes with incorporation of crystallizing admixtures and subjected to damage at early ages T1 - Avaliação do desempenho mecânico e absorção capilar de concretos com incorporação de aditivos cristalizante submetidos a danos nas primeiras idades N2 - This study assessed the self-healing phenomenon in the mechanical properties and capillary absorption of structural concretes. Two crystalline powder additives were evaluated, dosed according to the manufacturers’ recommendations. Crystalline additives increase the density of the C-S-H gel and form insoluble crystals, effectively blocking fissures. Three concrete mixes were produced: a reference mix, additive-X with 0.8%, and additive-Y with 2.0%, relative to the mass of cement. 75% of the rupture load was applied at 3- and 14-days to induce microfissures for comparison with the reference mix. Subsequently, self-healing was assessed at 28- and 76-days. The property of axial compressive strength was determined at 28-days, revealing that crystalline additives contributed to an average increase of 12% in this property. While the age of loading did not significantly impact axial compressive strength, there were significant variations among the types of additives studied, as indicated by ANOVA. Water absorption properties through capillarity were evaluated at 28- and 76-days, showing an average reduction of 42% in water absorption due to the use of crystalline additives. In conclusion, the inclusion of crystalline additives positively contributed to the self-healing of the studied concretes, suggesting a partial recovery of microfissures. N2 - Esta pesquisa avaliou o fenômeno de autocicatrização nas propriedades mecânicas e absorção capilar de concretos estruturais. Foram avaliados dois aditivos cristalizantes em pó, dosados de acordo com o teor recomendado pelos fabricantes. Aditivos cristalizantes aumentam a densidade do gel C-S-H e formam cristais insolúveis, bloqueando fissuras. Três traços de concreto foram produzidos: referência, aditivo-X com 0,8% e aditivo-Y com 2,0% em relação a massa do cimento. Aplicou-se 75% da carga de ruptura aos 3- e 14-dias para gerar microfissuras e comparar com a referência. Posteriormente, a autocicatrização foi avaliada aos 28- e 76-dias. A propriedade de resistência à compressão axial foi determinada aos 28-dias, revelando que os aditivos cristalizantes contribuíram para um aumento médio de 12% desta propriedade. A idade do carregamento dos concretos não apresentou um impacto significativo na resistência à compressão axial, mas apontou resultados significativos entre os tipos de aditivos estudados, conforme ANOVA. As propriedades de absorção de água por capilaridade foram avaliadas aos 28- e 76-dias, indicando uma redução de absorção de água média de 42% devido ao uso dos aditivos cristalizantes. Em conclusão, a incorporação dos aditivos cristalizantes contribuiu de maneira positiva para a autocicatrização dos concretos estudados, indicando uma recuperação parcial das microfissuras. KW - Self-healing KW - Crystalline admixture KW - Concrete KW - Cracks PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-599140 DO - https://doi.org/10.1590/1517-7076-RMAT-2023-0355 SN - 1517-7076 VL - 29 IS - 1 SP - 1 EP - 20 CY - Rio de Janeiro AN - OPUS4-59914 LA - por AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Sanchez Olivares, G. A1 - Rockel, Daniel A1 - Calderas, F. A1 - Schartel, Bernhard T1 - Utilizing leather fibers from industrial wastes as bio-filler to improve flame retardancy in polypropylene N2 - Combining buffing leather fibers from industrial waste streams with ammonium polyphosphate and bentonite clay is proposed as a flame-retardant additive for polypropylene. The paper addresses how they can be processed into attractive composites with the desired mechanical properties. Buffing leather fibers function as a multifunctional bio-filler and as a synergist for the flame retardant, resulting in fire retardancy successful enough to increase the oxygen index (LOI) by up to 7 vol.-% and to achieve a V0 UL 94 classification. Impressively reduced heat release rates are obtained in the cone calorimeter at 50 kW/m2 irradiation; for instance, the maximum average rate heat evolved (MARHE) drops from 765 to below 200 kW m􀀀 2. The synergistic effects are quantified and shown to be very strong for LOI and MARHE. This work opens the door to use waste buffing leather fibers as a promising multifunctional and synergistic bio-filler. KW - Polypropylene KW - Flame retardancy KW - Industrial waste KW - Leather fibers KW - Bio-filler PY - 2024 DO - https://doi.org/10.1016/j.jiec.2023.11.008 SN - 1226-086X SN - 1876-794X VL - 132 SP - 148 EP - 160 PB - Elsevier B.V. AN - OPUS4-59556 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Goller, Sebastian M. A1 - Schartel, Bernhard A1 - Krüger, Simone T1 - Block it and rock it: Smoke suppressants that form a protective layer in PA 6.6 N2 - To ensure fire safety, polymers are filled with flame retardants and smoke suppressants. To meet the highest requirements, it is essential to understand the decomposition of those polymeric materials. This study reveals interactions between polymer, smoke suppressants, and flame retardants, and discusses their impact on the materials’ flame retardancy, smoke emission, smoke toxicity, and particle emission in conventional loadings to provide deeper general understanding. Low melting oxide glass, melem, spherical silica, sepiolite, melamine polyphosphate, and boehmite in an aluminum diethylphosphinate flame-retarded polyamide 6.6 were investigated. All smoke suppressants improve the protective layer and act as an adjuvant. Silica and melem performed best under forced flaming conditions. Spherical silica reduces the peak of heat release rate by 39% and the total heat evolved by 14%, whereas 10 wt% melem lowers the total smoke production by 41%. Melem alters the mode of action of aluminum diethylphosphinate from gas to more condensed phase activity. This change reduces flame inhibition and hence smoke toxicity, but further improves the protective layer due to charring reactions in the decomposition mechanism. In addition, the sizes of the smoke particles decrease because of the prolonged time in the pyrolytic zone. This study highlights that interactions between polymer, flame retardants, and smoke suppressants can significantly determine the smoking and burning behavior. KW - Smoke suppressant KW - Flame retardancy KW - Aluminum diethylphosphinate KW - Smoke KW - Polyamide 6.6 PY - 2024 DO - https://doi.org/10.1177/07349041231220250 SN - 0734-9041 VL - 42 IS - 2 SP - 117 EP - 141 PB - SAGE Publications AN - OPUS4-59533 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Balscheit, Hagen T1 - Soil Embedded Piles - Reference Tests for Model Validation N2 - This presentation shows buckling tests on embedded piles conducted within the VERBATIM project. The generated data may serve as a valuable validation basis for numerical buckling design verification of Windenergy foundations in terms of the GMNIA concept. T2 - Buckling of Offshore Wind Energy Structures : 2-Day Buckling Colloquium CY - Berlin, Germany DA - 14.02.2024 KW - Wind Energy KW - Shell Buckling KW - Offshore Structures KW - GMNIA PY - 2024 AN - OPUS4-59536 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kapoor, M. A1 - Overgaard Christensen, Ch. A1 - Wittrup Schmidt, J. A1 - Dalsgaard Sørensen, J. A1 - Thöns, Sebastian T1 - Decision analytic approach for the reclassification of concrete bridges by using elastic limit information from proof loading N2 - Reclassification of bridges, i.e., a change in load rating, using reliability-based methods and a direct update with proof load information has been presented by many authors. However, bridge reclassification has hardly been studied from a decision analytic perspective, i.e., with quantification of the risks and benefits of different classification choices, and the expected benefit gain from proof loading. We derive, explain and exemplify a decision analytic approach for bridge reclassification along with models for (1) elastic and ultimate capacity and their adaptation with proof load information, (2) proof load information with classification outcomes accounting for target reliabilities and, (3) utilities including socio-economic benefits from reclassification. The approach and models are exemplified with a case study based on reclassification of bridges with a low existing classification. Decision rules, for practical use by a highway authority to find the optimal classification, are identified and documented based on: (1) the measurement of the capacity at elastic limit by proof loading, (2) the bridge reclassification benefits, and, (3) the required annual reliability level. From a Value of Information analysis, it is concluded that the proof load information is highly valuable for reclassification in cases of high socio-economic benefits and high reliability requirements. KW - Proof loading KW - Structural reliability KW - Value of information KW - Decision analysis PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-596845 DO - https://doi.org/10.1016/j.ress.2022.109049 SN - 0951-8320/ VL - 232 SP - 1 EP - 16 PB - Elsevier Ltd. AN - OPUS4-59684 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hupp, Vitus A1 - Schartel, Bernhard A1 - Flothmeier, K. A1 - Hartwig, A. T1 - Fire Behavior of Pressure-sensitive Adhesive Tapes and Bonded Materials N2 - Pressure-sensitive adhesive tapes are used in several industrial applications such as con-struction, railway vehicles and the automotive sector,where the burning behavior is ofcrucial importance. Flame retarded adhesivetapes are developed and provided, however,often without considering the interaction of adhesive tapes and the bonded materialsduring burning nor the contribution of the tapes to fire protection goal of the bondedcomponents in distinct fire tests. This publication delivers an empirical comprehensiveknowledge how adhesive tapes and their flame retardancy effect the burning behaviorof bonded materials. With a special focus on the interaction between the single compo-nents, one flame retarded tape and one tapewithout flame retardant are examined inscenarios of emerging and developing fires, along with their bonds with the commonmaterials wood, zinc-plated steel, mineral wool, polycarbonate, and polymethylmethacry-late. The flame retardant significantly improved the flame retardancy of the tape as afree-standing object and yielded a V-2 rating in UL 94 vertical test and raised the OxygenIndex by 5 vol.%. In bonds, or rather laminates, the investigations prove that the choiceof carrier and substrates are the factors with the greatest impact on the fire propertiesand can change the peak of heat release rate and the maximum average rate of heatemission up to 25%. This research yielded a good empirical overall understanding of thefire behavior of adhesive tapes and bonded materials. Thus, it serves as a guide for tapemanufacturers and applicants to develop tapes and bonds more substrate specific. KW - Adhesives KW - Cone calorimeter KW - Flame retardancy KW - Laminates KW - Phosphorus flame retardants KW - Pressure-sensitive adhesive KW - Tapes PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-593207 DO - https://doi.org/10.1002/fam.3171 SN - 0308-0501 SN - 1099-1018 VL - 48 IS - 1 SP - 114 EP - 127 PB - Wiley CY - New York, NY AN - OPUS4-59320 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schartel, Bernhard T1 - Flame Retardancy of Polymers - A Bunch of Thoughts N2 - Short overview is given of BAM's research within the topic "Flame Retardancy of Polymeric Materials". Fire science is identified as a crucial compentenc of BAM following our mission "Safety in Technology and Chemistry". In the area of polymers we work interdisciplinary, in the dimensions from nm to 2m, and we love to combine experiment and simulation. Multimethodical examples are given to describe the burning phenomena and flame-retardant modes of action. Further some examples are presented for tailored bench-scale fire testing and assessing concepts. Our goal is to provide the fundaments for a evidenced-based development of future materials. T2 - Klausurtagung Transregio 150 CY - Weinheim, Germany DA - 21.11.2023 KW - Flame retardants KW - Mode of action KW - Flame retardancy concepts KW - Flame inhibition KW - Protective layer KW - Charring KW - Dripping KW - Synergy PY - 2023 AN - OPUS4-58899 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Faghih-Naini, Sara A1 - Kuckuk, Sebastian A1 - Zint, Daniel A1 - Kemmler, Samuel A1 - Köstler, Harald A1 - Aizinger, Vadym T1 - Discontinuous Galerkin method for the shallow water equations on complex domains using masked block-structured grids N2 - We evaluate masked block-structured grids for ocean domains which allow to represent small-scale geometric features without resorting to very small blocks or excessive mesh resolution. The considered approach aims to combine the geometric flexibility of unstructured meshes with the computational efficiency of stencil-based discretizations and is implemented and tested in a quadrature-free discontinuous Galerkin shallow water solver. We investigate the accuracy and the computational performance of the scheme on a range of realistic ocean domains meshed with blocks of different size and provide some comparisons to results obtained on unmasked block-structured grids and unstructured meshes. KW - Water Science and Technology PY - 2023 DO - https://doi.org/10.1016/j.advwatres.2023.104584 VL - 182 SP - 1 EP - 11 PB - Elsevier AN - OPUS4-58884 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Bruhn, D. A1 - Köhler, S. A1 - Regenspurg, S. A1 - Schumann, F. A1 - Bäßler, Ralph A1 - Dunkelberg, E. A1 - Huenges, E. A1 - Frick, M. A1 - Hirschl, B. A1 - Sass, I. T1 - Positionspapier Wärmeversorgung in Berlin und Brandenburg durch GeoEnergie - Empfehlungen der GeoEnergie Allianz Berlin Brandenburg zu Forschung und Umsetzung N2 - Das gesellschaftliche Ziel der Defossilisierung der Energieversorgung erfordert eine disruptive Veränderung der Wärmebereitstellung. In Berlin und in den größten Brandenburger Städten Potsdam und Cottbus werden noch über 80 % der Nutzwärme über fossile Energieträger bereitgestellt. Die notwendigen Veränderungen erfordern Lösungen, die den tiefen Untergrund der Region nutzen. Allein die Nutzung der tiefen Geothermie kann mindestens 25% des Wärmebedarfs in Deutschland decken. Die Infrastruktur zur Verteilung dieser erneuerbaren Wärme ist bereichsweise vorhanden. Sie muss allerdings lokal und in ländlichen Gebieten weiter ausgebaut werden. Für die Sektoren Strom und Verkehr steht zwar Energie insbesondere aus Sonne und Wind bereit, aber wegen des zeitlich variablen Angebots besteht ein erheblicher Bedarf an großtechnischen Speichern für Strom und Wärme oder auch für Energieträger (z. B. Wasserstoff). Die saisonale oder temporale Überproduktion an Strom und Wärme aus erneuerbaren Energien zwingt dazu, eine urbane Speicherinfrastruktur aufzubauen, um eine grundlastfähige und bedarfsgerechte Lieferung zu realisieren. Hinzu kommt die Aufgabe das Treibhausgas Kohlendioxid aus der Atmosphäre zu reduzieren und unterirdisch dauerhaft zu lagern. Auch hier werden Speichertechnologien und ‐räume benötigt. Die nachhaltige energetische Nutzung des unterirdischen Raumes ist geeignet, entscheidende Beiträge zu einer zukünftigen Energiewirtschaft ohne fossile Brennstoffe zu leisten. Diese große interdisziplinäre Aufgabe erfordert die Zusammenarbeit vieler Fach‐, und Forschungseinrichtungen, die im Raum Berlin‐ Brandenburg vorhanden sind und in einer regionalen Forschungsallianz gebündelt werden sollen. Für die Region Berlin‐Brandenburg ergibt sich daraus die Chance, eine Schlüsselrolle in der Grundlagen‐ und angewandter Forschung zur Transformation des Energiesystems zu übernehmen und weltweit als Vorbild zu dienen. Im vorliegenden Papier werden die Formen einer nachhaltigen Geoenergienutzung, das geologische Potenzial der Region Berlin Brandenburg und dessen bisherige geoenergetische Nutzung dargestellt. Aus diesem Wissen wird der Ist‐Zustand hinsichtlich des energiewirtschaftlichen Potenzials und der sich daraus ergebenden Nutzungsoptionen abgeleitet, um darauf aufbauend Maßnahmen darzustellen, mit denen spürbare Beiträge zur Dekarbonisierung erreicht werden können. Daraus ergeben sich Handlungsempfehlungen für die Region, verbunden mit einem möglichen Beitrag der GEB² zum Risikomanagement, Investitionen in Schlüsseltechnologien, der Aus‐ und Weiterbildung, sowie der Akzeptanzerhöhung für geoenergetische Projekte. T2 - Gründungsveranstaltung der GeoEnergie Allianz Berlin Brandenburg CY - Berlin, Germany DA - 24.11.2023 KW - Geoenergie KW - Geothermie KW - Nachhaltigkeit PY - 2023 SP - 1 EP - 18 CY - Berlin & Potsdam AN - OPUS4-58924 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Zinas, Orestis T1 - 3D Probabilistic Site Characterization N2 - The aim of the study is to infer the soil stratification from the provided CPT and borehole data. We infer the soil type at any location within the domain of interest from the SBT index Ic (Robertson, 2009). This index can be directly related to the CPT data through an empirical correlation model. In addition, the soil classes contained in the borehole logs can be expressed as bounds on Ic. A log-transformation was applied to Ic, Y = ln(Ic), and Y was modelled by a 3D Random Field, with a fully Bayesian hierarchical Gaussian Process model to explicitly capture uncertainties. T2 - 19th eawe PhD Seminar CY - Hannover, Germany DA - 06.09.2023 KW - Wind Energy KW - Site-characterization KW - Probabilistic PY - 2023 AN - OPUS4-58940 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rockel, Daniel T1 - Save your Skin with Skin – utiLizing leather waste fibers in flame retardant bio composites N2 - Leather is a widely used material for thousands of years and in modern days it is produced on industrial scale. This production produces high amounts of organic waste during the tannery process. These fibers can become a resource and act as a multi-functional bio-filler in flame retardant composites. This project investigates two leather fibers towards their ability to enhance the flame-retardancy in different composites. These composites use ammonium polyphosphate (APP) or aluminum trihydroxide (ATH) as flame retardants. Different silicon based synergists support polymers with ATH to reduce the load of flame retardant. The different modes of action (charring, gas phase activity, barrier effect) can be quantified of each composite. The new composites form a stable char layer resulting in an increase in residue, lower peak heat release rates (pHRR) and higher limiting oxygen index (LOI). In addition, the ratings in the UL94-classification increased up to V-0. T2 - 18th Fire Resistance in Plastics CY - Berlin, Germany DA - 20.11.2023 KW - Leather KW - Synergism KW - Sustainability KW - Bio-Polymers KW - Flame retardancy KW - Composites PY - 2023 AN - OPUS4-58948 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Cook, Jake Thomas T1 - Assessment of concrete bioreceptivity in algal biofilm green façade systems N2 - Content: Why Algal Biofilm Green Façade Systems?, Factors Influencing Bioreceptivity, Influence of pH and Microorganism Symbiosis, Pulse-Amplitude-Modulation (PAM) Fluorometry T2 - International Conference on Bio-Based Building Materials CY - Vienna, Austria DA - 21.06.2023 KW - Concrete KW - Façade KW - Bio-receptive KW - Extracellular polymeric substances KW - Fractional factorial PY - 2023 UR - https://www.rilem.net/agenda/5th-international-conference-on-bio-based-building-materials-1501 AN - OPUS4-58962 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Cook, Jake Thomas T1 - Assessment of concrete bioreceptivity in algal biofilm green façade systems N2 - Algal biofilm façades are an alternative to traditional green façades which can help to improve biodiversity and air quality within cities. They present a low maintenance approach in which subaerial algae are grown directly on concrete substrates. The intrinsic bioreceptivity of the substrate is a critical factor in successful facade colonisation. Existing research has identified several environmental and material properties which influence concrete bioreceptivity, however a consensus has yet to be made on which properties are most influential and how the interaction between properties may promote algal biofilm growth under specific conditions. T2 - International Conference on Bio-Based Building Materials CY - Vienna, Austria DA - 21.06.2023 KW - Concrete KW - Façade KW - Bio-receptive KW - Extracellular polymeric substances KW - Fractional factorial PY - 2023 UR - https://www.rilem.net/agenda/5th-international-conference-on-bio-based-building-materials-1501 AN - OPUS4-58976 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ritz, Sebastian A1 - Loewe, Anna A1 - Bauer, Jan T1 - Specialties of HAZID-Study for Large Unmanned Underwater Vehicles N2 - This paper scopes the specialties of a hazard identification study for large and extra-large unmanned undersea vehicles (UUVs). A generic node/function structure is derived from different large and extra-large UUV designs, partially own vehicle designs from research projects, and partially from commercial vehicles. For each node, a short overview of its components and the proper function or operations is defined. A set of guide words is used to prompt a hazard discussion for each node, which identifies unwanted functions, resulting in potential hazards and unmitigated consequences. Related to the SafeMASS-Report from DNV, this work concentrates on selected topics of the bridge-related function on voyage, control & monitoring, and abnormal situations. For unmanned vehicles without any person on board, these three topics become more important for underwater vehicles with very limited connectivity or temporary disruptions of communication whereby an operator in a remote-control center could only be provided with rough vehicle or mission states. Therefore, vehicle control, whether in hard- or software, must handle most tasks belonging to the considered functions automatically or autonomously. Hence, the most appropriate reactions of the system to unwanted system behavior must be implemented. This HAZID study could, on the one hand, be used as background for such an implementation, and on the other hand, it is used to verify the implemented actions on the risks and hazards. T2 - OCEANS 2023 - Limerick CY - Limerick, Ireland DA - 05.06.2023 KW - Autonomous underwater vehicles KW - HAZID KW - Risk-based design KW - Safety KW - Cyber security PY - 2023 DO - https://doi.org/10.1109/OCEANSLimerick52467.2023.10244358 SP - 1 EP - 10 PB - IEEE AN - OPUS4-59099 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Turski Silva Diniz, Analice A1 - Marti, J. M. A1 - Schartel, Bernhard T1 - High Heat Resistance Can Be Deceiving: Dripping Behavior of Polyamide 4.6 in Fire N2 - Polyamide 4.6 (PA46) is a high-heat-resistant polymer, but it has no dripping resistance under fire. Three commercial grades of PA46 are investigated under UL 94 vertical fire test conditions. Their performances are discussed based on the materials’ structural, thermal, and rheological properties. PA46 presents flaming drops, whereas dripping is prevented in the flame-retarded PA46. Friction-modified PA46 has increased flaming dripping. Temperature profiles of the specimens under fire and the temperature of the drops are measured by thermocouples. A UL 94 vertical test configuration consisting of two flame applications is designed to assess the quantitative dripping behavior of the set of materials by the particle finite element method (PFEM). Polymer properties (activation energy and Arrhenius coefficient of decomposition, char yield, density, effective heat of combustion, heat of decomposition, specific heat capacity, and thermal conductivity) in addition to rheological responses in high temperatures are estimated and measured as input parameters for the simulations. The dripping behavior obtained by simulated materials corresponds with the experimental results in terms of time and drop size. A consistent picture of the interplay of the different phenomena controlling dripping under fire appears to deliver a better understanding of the role of different materials’ properties KW - Dripping KW - UL 94 KW - PFEM KW - High heat resistance KW - Polyamide 4.6 KW - Flammability PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-586015 DO - https://doi.org/10.1002/mame.202300091 SN - 1439-2054 SN - 1438-7492 VL - 308 IS - 10 SP - 1 EP - 11 PB - Wiley-VCH AN - OPUS4-58601 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Lehmann, Jens T1 - Offshore Auslagerung von Stahlcoupons N2 - Darstellung von Ergebnissen einer Auslagerungskampagne auf dem EnBW Windpark Hohe See. T2 - 2. Sitzung GfKORR Arbeitskreis “Atmosphärische Korrosion” CY - Berlin, Germany DA - 24.10.2023 KW - Korrosion KW - Offshore KW - Atmosphärische Korrosion KW - ISO 9223 PY - 2023 AN - OPUS4-58685 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schepers, Winfried A1 - Kulke, D. ED - Wuttke, F. ED - Aji, H. D. B. ED - Özarmut, A. T1 - Anwendung von Korrelationen zwischen Sondierergebnissen und dynamischen Bodeneigenschaften N2 - Die natürliche Variabilität des Bodens bewirkt, dass jegliche in-situ Messung dynamischer Bodenparameter stets nur den Untersuchungsort beschreiben, und jede Verwendung für benachbarte Orte bereits eine Extrapolation ist. Gleichzeitig ist die Ermittlung von Bodeneigenschaften in-situ mit erheblichen Kosten verbunden, insbesondere bei Standorten wie z. B. Offshore-Windparks. Im innerstädtischen Raum sind seismische Messungen wegen der vorhandenen Bebauung und Flächenversiegelungen nur eingeschränkt möglich. Es bietet sich daher an, indirekte Methoden auf Basis von Drucksondierungen anzuwenden, weil diese Untersuchungen inzwischen zum Standardrepertoire selbst bei kleineren Bauvorhaben gehören. Der neue nationale Anhang zu DIN EN 1998-1 erlaubt die Anwendung von Korrelationen zwischen Sondierergebnissen und dynamischen Bodeneigenschaften zur Anwendung bei seismischen Standortanalysen. Es werden jedoch keine Hinweise zur Auswahl geeigneter Korrelationen gegeben. Mit ISO/TS 14837-32 liegt ein Standard vor, in dem sogar für sandartigen Boden und tonartigen Boden zwei konkrete Korrelationen zur Anwendung vorgeschlagen werden. Dasselbe gilt für den Entwurf des Eurocode 7-2, prEN 1997-2 von 2022. Untersuchungen zeigen, dass seismische Verfahren, wenn sie nicht unter Labor-Freifeldbedingungen durchgeführt werden, signifikante Streuungen aufweisen. Sofern statistische Korrelationen eine Streuung aufweisen, die in derselben Größenordnung liegen wie Ergebnisse seismischer Verfahren, können beide Verfahren in Grundsatz alternativ eingesetzt werden. Wir zeigen, dass bei homogenen ausgeprägt sandartigen Böden mit statistisch ermittelten Korrelationen die dynamischen Bodensteifigkeiten mit einer Genauigkeit abgeschätzt werden können, die mit der Ungenauigkeit der seismischen Verfahren übereinstimmt. Mit zunehmenden Feinkornanteil werden die Unsicherheiten der statistischen Korrelationen größer. Bei stark überkonsolidierten glazialen Böden sollte von der Anwendung empirischer Korrelationen Abstand genommen werden. T2 - 18. D-A-CH-Tagung Erdbebeningenieurwesen und Baudynamik CY - Kiel, Germany DA - 14.09.2023 KW - Scherwellengeschwindigkeit KW - Schubmodul KW - Wellenausbreitung KW - Bodenvariabilität KW - Statistische Auswertung PY - 2023 SN - 978-3-930108-15-1 SP - 433 EP - 441 PB - Deutsche Gesellschaft für Erdbebeningenieurwesen und Baudynamik (DGEB) e. V. und Christian-Albrechts-Universität zu Kiel CY - Kiel AN - OPUS4-58351 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Erning, Johann Wilhelm T1 - “Grabenkorrosion": How scientific debate leads to an solution. and modern failures due to neglection of well described facts N2 - In the late 1980s, a new type of corrosion appeared in drinking water installations where galvanized steel pipes failed forming a deep groove with no corrosion at the other surfaces. The reason was discussed quite fiercely between failure analysts and material suppliers. In the end the discussion lead to the solution: inductive welded pipes of a certain sulphur content were prone to selective corrosion. The history of the arguments is discussed using old communications between Wilhelm Schwenk and Wolfgang Stichel, who later published the results in a paper unfortunately only I german. Thus the knowledge got lost and new cases based on the same material problems are observed in application of so-called C-Steel piping systems. Failure cases are shown. T2 - MTech 2023 CY - Cavtat, Croatia DA - 02.10.2023 KW - Corrosion KW - Grabenkorrosion PY - 2023 SN - 2806-8769 SP - 1 EP - 6 PB - Croatian Society for Heat Treatment and Sufrace Engineering CY - Zagreb AN - OPUS4-58521 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Denkler, Tilman T1 - OITB Quality Assurance concept and minimum requirements for testing services offered on the Metabuilding platform N2 - A brief description of the Quality Assurance concept of the Metabuilding Labs Open Ivvovation Test Bed (OITB) and presentation of the minimum requirements for testing services offered on the Metabuilding platform, wehich were elaborated in 2 workshops in summer 2023. T2 - 4th General Meeting of the Metabuilding Labs project (Horizon 2020) CY - Valladolid, Spain DA - 10.10.2023 KW - Open Innovation Test Bed KW - Metabuilding Labs PY - 2023 AN - OPUS4-58566 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Denkler, Tilman T1 - O3BET Quality Protocols N2 - Presentation of the process-oriented approach for the development of the quality protocolls (standard operation procedures and work instructions) for the O3BETs. O3BETs are innovative testing facilities for building envelopes which are developed in the course of the Metabuilding Labs EU Horizon 2020 project. T2 - 4th General Meeting of the Metabuilding Labs project (Horizon 2020) CY - Valladolid, Spain DA - 10.10.2023 KW - Open Innovation Test Bed KW - Metabuilding Labs KW - O3BET PY - 2023 AN - OPUS4-58567 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Häßler, Dustin T1 - Durability of intumescent coatings N2 - For intumescent coatings durability is an important aspect. Due to ageing, which is caused by climatic conditions, the thermal protection performance of intumescent coatings can be reduced during the working life. The national German and the European procedures to assess the durability of intumescent coatings presume a working life of 10 years. For a longer period, additional investigations are required. However, the European assessment procedure does not provide specific information how to prove a durability of more than 10 years. In addition to this formal reason, also from a scientifical position, it is necessary to investigate the degradation of intumescent coatings in detail to propose a corresponding test concept for a durability of more than 10 years. The presentation summarises the existing knowledge about the degradation behaviour and ageing of intumescent coatings. Furthermore, the results of different approaches from a recently conducted research project are presented. Starting from a water-based and an epoxy-based guide formulation, in a first approach a degradation of the intumescent coating was carried out directly during the production process, i.e. by reducing the concentration of functionally relevant chemical components. In another approach, the duration of the short-term weathering tests was significantly extended, i.e. by multiple repetition of the artificial weathering. The thermal protection performance of the intumescent coating was assessed by fire tests and tests with electrical heating source. In addition, small-scale tests were carried out to determine the thermal material properties of the intumescent coating and thermo-analytical methods were applied to characterise the degradation. Derived from this knowledge, possibilities to test and assess a working life for a period of more than 10 years are proposed. T2 - European Conference - Protective & Fire-Retardant Coatings CY - Berlin, Germany DA - 18.10.2023 KW - Intumescent coating KW - Steel KW - Fire protection KW - Durability PY - 2023 AN - OPUS4-58637 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Amano, Kofi Owusu Ansah T1 - Study of thermal runaway and gas emissions in NMC lithium-ion batteries: State of Charge Dependence Investigation N2 - Thermal runaway investigations were performed by subjecting single and double NMC pouch cells to thermal abuse condition inside an air-tight reactor vessel with an internal volume of 100 dm³. The study was divided into two series. The findings revealed the thermal runaway-induced explosion in the cells results in a rate of temperature increase greater than 10 K/s. The highest gaseous production was achieved at a range of 90 – 100% SOC and higher battery capacities 0.79 L/Wh (Series 1, 10 Ah cell) and 0.87 L/Wh (Series 2, 32 Ah cell). The investigation showed between 25 m³ and 84 m³ of explosible gas mixture could be released from electric vehicles of nominal useable electrical energy from 32 kWh up to 108 kWh at thermal runaway. It was also found that, the release of these explosible gases could undergo a secondary explosion. T2 - 4th IBSW 2023 – International Battery Safety Workshop CY - Ulm, Germany DA - 28.09.2023 KW - Consequneces KW - Electrical Energy Storage KW - Propagation; Gas release KW - Lithium-ion battery PY - 2023 AN - OPUS4-58543 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schepers, Winfried T1 - Korrelationen zwischen Sondierungen und dynamischen Bodeneigenschaften N2 - Wir zeigen, dass bei homogenen ausgeprägt sandartigen Böden mit statistisch ermittelten Korrelationen die dynamischen Bodensteifigkeiten mit einer Genauigkeit abgeschätzt werden können, die mit der Ungenauigkeit der seismischen Verfahren übereinstimmt. Mit zunehmenden Feinkornanteil werden die Unsicherheiten der statistischen Korrelationen größer. Bei stark überkonsolidierten glazialen Böden sollte von der Anwendung empirischer Korrelationen Abstand genommen werden. T2 - 18. D-A-CH-Tagung für Erdbebeningenieurwesen und Baudynamik CY - Kiel, Germany DA - 14.09.2023 KW - Baugrunddynamik KW - Dynamische Bodenkennwerte KW - Statistische Korrelationen PY - 2023 AN - OPUS4-58581 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schepers, Winfried T1 - Cone penetration tests and dynamic soil properties N2 - Current standards like ISO 14837-32:2015 and DIN EN 1998-1/NA:2021 as well as prEN 1997-2:2022 allow for using correlations between the results of in-situ soil penetration tests and shear wave velocity (or shear modulus) to determine soil properties to be used in dynamic analyses. While the ISO and prEN standards even provide some recommendations on specific correlations to be used, the DIN standard does not. Due to the statistical nature of such correlations their general applicability has to be verified. We collected data sets from test sites from Germany as well as New Zealand at which cone penetration tests (CPT) as well as seismic site investigation methods were conducted. These sites comprise sandy soils as well as clayey soils, mixed soils as well as glacial soils. We compare the results of several correlations between CPT results and shear wave velocity. The accuracy of such correlations is assessed with respect to the accuracy of seismic in-situ tests. It turns out that for clean sands such correlations between CPT and Vs have a similar order of variability as seismic in-situ tests conducted at the same site. The higher the fines portion of the soil, the higher the variability of the statistical correlations, and consequently the less the general applicability. For glacial soils and other special soil types usage of statistical correlations to determine dynamic soil properties is not recommended. T2 - Eurodyn 2023 CY - Delft, Netherlands DA - 02.07.2023 KW - Dynamic soil properties KW - Statistical correlations PY - 2023 AN - OPUS4-58582 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schepers, Winfried T1 - Recommendations on finite Element modelling of non-seismic excitation in soil-structure interaction problems N2 - Nowadays geotechnical engineering firms have powerful software tools to extent their consulting business also into dynamic soil-structure interaction, which before has been restricted to a rather small community of specialized experts in this field, and they certainly do. This is particularly true with respect to non-seismic sources, that is all kinds of human induced vibrations. Hence, there is a demand from clients as well as from contractors to have guidance on the requirements as well as the limits of numerical modelling of soil-structure interaction. From the literature as well as from relevant standards, recommendations for the numerical modelling of soil-structure interaction problems involving seismic actions are well known, e. g. ASCE/SEI 4-16. There are, however, some particularities when dealing with human-induced vibrations, which are absent in seismic analyses. For human-induced excitations very little specific guidance has been published in the past. A machine foundation on a homogeneous half space excited by harmonic loads with excitation frequency between 4 Hz and 64 Hz has been analysed by means of several commercially available software packages. Parametric studies have been performed to verify if recommendations for seismic soil-structure analyses are valid for non-seismic analyses as well. This paper provides details on the benchmark example and the most important conclusions from the undertaken parametric studies. T2 - Eurodyn 2023 CY - Delft, Netherlands DA - 02.07.2023 KW - Numerical analysis KW - Vibrations KW - Soil-structure interaction PY - 2023 AN - OPUS4-58583 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Appel, S. A1 - Schepers, Winfried T1 - Tieffrequente Schwingungsimmissionen durch den Betrieb einer Rohzementmühle N2 - Der Beitrag berichtet von einer aufwändigen Messkampagne vor Ort, mit der die Emissionen direkt an einer Rohzementmühle, die Transmissionen im Baugrund und die Immissionen in benachbarten Bebauungen genauer untersucht wurden. Im Ergebnis der ausgewerteten Messungen sowie strukturdynamischer Berechnungen zeigte sich, dass der Baugrund zwar aus statischer Sicht sehr gut tragfähig, aber dynamisch als eher ungünstig zu beurteilen ist. Weiterhin wurde festgestellt, dass in dynamischer Hinsicht ein vorgenommener Bodenaustausch tendenziell eine Verschlechterung der Aufstellbedingungen darstellte. Für das betroffene Bürogebäude konnte nachgewiesen werden, dass durch den Betrieb der Zementmühle die Anregung der Deckeneigenfrequenzen zu deutlich spürbaren Resonanzschwingungen führte. Aufgrund der tieffrequenten Anregung durch den Mühlenbetrieb sind Maßnahmen zur Minderung der Schwingungsemissionen generell und insbesondere nach erfolgter Aufstellung der Mühle schwer bzw. gar nicht zu realisieren. Im Beitrag wird daher darauf eingegangen, auf welche Aspekte bei der Planung zur Aufstellung derart großer Mühlen zwingend zu achten ist. T2 - 7. VDI-Fachtagung Baudynamik CY - Würzburg, Germany DA - 27.04.2022 KW - Erschütterungen KW - Maschinenbetrieb KW - Minderungsmaßnahmen PY - 2022 SN - 978-3-18-092379-6 SP - 385 EP - 397 PB - VDI-Verlag CY - Düsseldorf AN - OPUS4-58584 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Eichner, Lukas T1 - Design of offshore jacket support structure for experimental fatigue life evaluation N2 - One crucial metric of interest to wind farm operators is the remaining useful life (RUL) of single components, wind turbines, or even entire wind farms. Occasionally, questions arise regarding how to operate a turbine, even in the presence of manufacturing or design errors, which from a computational design standpoint reduce the remaining lifetime below the intended service life. A typical measure involves adapting the monitoring and inspection plan. Using such a maintenance plan, the author intends to simulate the lifetime of jacket-type structure in a fatigue test. The objective of the experiment is to demostrate that systems like three-dimensional jackets possess redundancies that enable reliable continued operation, despite the reduced fatigue life of individual components due to technical flaws, if an appropriate maintenance concept is in place. This presentation discusses the steps leading to the procedure of the experiment including the design process and the maintenance planning. T2 - 19th eawe PhD Seminar CY - Hannover, Germany DA - 06.09.2023 KW - Offshore wind energy KW - Jacket support structure KW - Simulation and experiment KW - Structural integrity management KW - Risk-based maintenance planning PY - 2023 AN - OPUS4-58240 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rockel, Daniel T1 - Save your Skin with Skin – Utilizing leather waste fibers in flame retardant bio composites N2 - Leather is a widely used material for thousands of years and in modern days it is produced on industrial scale. This production produces high amounts of organic waste during the tannery process. These fibers can become a resource and act as a multi-functional bio-filler in flame retardant composites. This project investigates two leather fibers towards their ability to enhance the flame-retardancy in different composites. These composites use ammonium polyphosphate (APP) or aluminum trihydroxide (ATH) as flame retardants. Different synergists support polymers with ATH. The new composites form a stable char layer resulting in an increase in residue, lower peak heat release rates (pHRR) and higher limiting oxygen index (LOI). In addition, the ratings in the UL94-classification increased up to V-0. T2 - 5th Asia-Oceania Symposium on Fire Safety Materials Science and Engineering CY - Sydney, Australia DA - 26.08.2023 KW - Leather KW - Circular Economy KW - Sustainability KW - Bio-Polymers KW - Flame retardancy KW - Composites PY - 2023 AN - OPUS4-58241 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - RPRT A1 - Schaumann, P. A1 - Hothan, Sascha A1 - Mund, M. A1 - Häßler, Dustin A1 - Schartel, Bernhard A1 - Daus, Lars-Hendrik T1 - Bewertung des Feuerwiderstandes von Stahlkonstruktionen mit reaktiven Brandschutzsystemen unter Berücksichtigung des Alterungsverhaltens N2 - Im Rahmen des Forschungsprojektes IGF 20470N wurden Untersuchungen zum Alterungsverhalten von reaktiven Brandschutzsystemen (RBS) auf Stahlbauteilen durchgeführt. Mithilfe der Ergebnisse einer umfangreichen Literaturrecherche sowie experimentellen und numerischen Untersuchungen sollte ein Vorschlag für ein Prüfkonzept zum Nachweis einer Nutzungsdauer von RBS von mehr als 10 Jahren auf Basis von Kurzzeitversuchen abgeleitet werden. Dabei setzt die Bewertung des Alterungsverhaltens von RBS voraus, dass die Mechanismen der Alterung hinreichend bekannt sind. Dafür wurden zunächst systematisch Daten von Kurz- und Langzeitversuchen von nationalen Zulassungsprüfungen der letzten Jahrzehnte ausgewertet. Anschließend wurden umfangreiche experimentelle Untersuchungen an einer wasserbasierten sowie einer epoxidharzbasierten Richtrezeptur durchgeführt. Da aus der Literatur bekannt ist, dass die Einflüsse der Bewitterung zu einer Veränderung der Konzentration der Bestandteile innerhalb der Beschichtung führen können, wurden Untersuchungen mit Mangelrezepturen durchgeführt, wobei systematisch einzelne Bestandteile reduziert wurden. Neben optischen Untersuchungen wurden thermoanalytische Verfahren (DSC-TG-, ATR-FTIR-, Elementar-, Farbanalyse) angewandt sowie Brandversuche an beschichteten Stahlplatten durchgeführt. Des Weiteren wurden die Richtrezepturen den beschleunigten Kurzzeitversuchen gemäß EAD 350402-00-1106 (2017) unterzogen, welche die Zulassung von Produkten auf europäischer Ebene regelt. Für die wasserbasierte Richtrezeptur wurden die Bewitterung für den feuchten Innenraum (Typ Z1) mehrfach wiederholt (1x, 3x, 6x). Für die epoxidharzbasierte Richtrezeptur entsprach die Bewitterung dem Zyklus für die Außenanwendung (Typ X). In Brandversuchen sowie thermoanalytischen und optischen Untersuchungen wurde das Alterungsverhalten sowie die thermische Schutzwirkung analysiert. Anschließend wurden numerische Simulationen von Stahlbauteilen mit gealterten RBS durchgeführt und anhand der experimentellen Untersuchungen validiert. Mithilfe der numerischen Modelle kann eine Bewertung der thermischen Schutzwirkung von Stahlbauteilen mit gealterten RBS vorgenommen werden. Mithilfe der gesammelten Erkenntnisse wurde ein Vorschlag für ein Prüfkonzept für den Nachweis einer Nutzungsdauer von mehr als 10 Jahren abgeleitet. Das Prüfkonzept besteht dabei aus einem Katalog von Möglichkeiten, die aktuellen Zulassungsprüfungen auf europäischer Ebene für eine Nutzungsdauer von 10 Jahren auf einen längeren Zeitraum zu erweitern. N2 - Within the scope of the research project IGF 20470N, investigations were carried out on the assessment of the aging behavior of intumescent coatings (ICs) for the fire protection of steel members. With the help of the results of an extensive literature research as well as experimental and numerical investigations, a proposal for a test concept for the proof of a service life of ICs of more than 10 years was to be derived on the basis of short-term tests. The evaluation of the aging behavior of ICs presupposes that the aging mechanisms are sufficiently known. For this purpose, data from short- and long-term tests of national approval tests of the last decades were first systematically evaluated. Subsequently, extensive experimental investigations were carried out on a water-based and epoxy resin-based model formulation. Since it is known from the literature that the effects of weathering may lead to a change in the concentrations of the constituents within the coating, investigations were carried out with formulations of the ICs in which individual constituents were systematically reduced. In addition to optical investigations, thermoanalytical methods (DSC-TG-, ATR-FTIR-, elemental-, color analysis) were used and fire tests were carried out on coated steel plates. Furthermore, the model formulations were subjected to the accelerated short-term tests of EAD 350402-00-1106 (2017), which regulates the approval of products at the European level. For the water-based model formulation, the weathering for the interior application with a high moisture content (type Z1) was repeated several times (1x, 3x, 6x). For the epoxy resin-based model formulation, the weathering corresponded to the cycle for exterior application (type X). Fire tests as well as thermoanalytical and optical investigations were carried out to analyze the aging behavior and the thermal protection performance. Subsequently, numerical simulations of steel members with aged ICs were carried out and validated on the basis of the experimental investigations. With the help of the numerical models, an evaluation of the thermal protection performance of steel members with aged ICs can be carried out. Bases on the findings, a proposal for a test concept for the verification of a service life of more than 10 years was derived. The test concept consists of a catalogue of possibilities for extending the current approval tests at European level for a service life of 10 years to a longer period. KW - Brandschutz KW - Dauerhaftigkeit KW - Alterung KW - Reaktive Brandschutzsysteme KW - Brandversuche PY - 2022 UR - https://dast.deutscherstahlbau.de/veroeffentlichungen/forschungsberichte SP - 1 EP - 367 PB - Stahlbau Verlags- und Service GmbH CY - Düsseldorf AN - OPUS4-57257 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Goller, Sebastian M. A1 - Krüger, Simone A1 - Schartel, Bernhard T1 - No business as usual: The effect of smoke suppressants commonly used in the flame retardant PA6.6 on smoke and fire properties N2 - As most of polymeric materials are inherently flammable, flame retardants (FR) are commonly used to reduce their fire risks. Nevertheless, these flame retardant materials are often detrimental to smoke parameters like specific optical density or smoke toxicity. The influence of several smoke suppressants (SP)-zinc stannate, zinc phosphate, titanium oxide and hydrotalcite-were investigated with respect to flame retardancy, smoke emission, particle emission and smoke toxicity in a diethyl aluminum phosphinate (AlPi) flame retardant polyamide 6.6 (PA6.6). It was shown that the interaction between SP, FR and polymer is crucial for smoke and fire properties and can change the mode of action of the FR as well the decomposition mechanism of the polymer. Small amounts of SP show less effect on forced flaming behavior and the optical density, but they can influence flammability and the particle size distribution of the soot particles. The flame retardancy was significantly enhanced by 5 wt.-% zinc stannate in PA6.6 under forced flaming conditions. The charring mechanism was improved, and the mode of action of AlPi switched from the gas to the condensed phase. This resulted of in a reduced PHRR and TSP and an increase in residue yield. The smoke toxicity and optical density were reduced in the smoke density chamber as well. The smoke particles shifted to smaller sizes as the time in the pyrolytic zone increased. The formation of a dense char is assumed to be the key factor to enhance smoke suppression and flame retardancy properties. KW - Polyamide 6.6 KW - Smoke suppression KW - Flame retardancy KW - Zinc stannate KW - Smoke density PY - 2023 DO - https://doi.org/10.1016/j.polymdegradstab.2023.110276 SN - 0141-3910 VL - 209 PB - Elsevier Ltd. AN - OPUS4-56981 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kinne, Marko A1 - Thöns, Sebastian T1 - Fatigue Reliability Based on Predicted Posterior Stress Ranges Determined from Strain Measurements of Wind Turbine Support Structures N2 - In the present paper, an approach for updating the continuous stress range distribution of a welded connection of a wind turbine support structure with predicted information from strain measurements is presented. Environmental conditions, such as wind or, in offshore fields, waves and currents, in combination with rotor excitations generate cyclic stresses affecting the reliability of welded joints of the support structure over the service life. Using strain measurements, these conditions can be monitored, and the resulting stress ranges, under consideration of measurement, mechanical and material uncertainties, can be reconstructed. These stress ranges can be used as an input for updating the prior probability density function (PDF) of the stress ranges predicted by the overall dynamics and a detailed design analysis. Applying Bayesian probability theory and decision theoretical implications, the predicted posterior probability density of the stress ranges is calculated based on the design information and uncertainties. This approach is exemplified, and it is shown how the predicted stress ranges and the design stress ranges are distributed. The prior and the predicted posterior stress ranges are used for a reliability calculation for potentially entering a pre-posterior decision analysis KW - Strain measurements of wind turbine support structures KW - Bayesian updating of stress ranges KW - Posterior fatigue reliability PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-572663 DO - https://doi.org/10.3390/en16052225 VL - 16 IS - 5 SP - 1 EP - 26 PB - MDPI AN - OPUS4-57266 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kinne, Marko A1 - Farhan, Muhammad A1 - Schneider, Ronald A1 - Thöns, Sebastian T1 - Influence of the structural integrity management on the levelized cost of energy of offshore wind: a parametric sensitivity analysis N2 - The levelized cost of energy (LCoE) is an important measure to quantify the macro-economic efficiency of an offshore wind farm and to enable a quantitative comparison with other types of energy production. The costs of the structural integrity management - which is required to ensure an adequate lifetime reliability of the turbine support structures - are part of the operational expenditures of an offshore wind farm. An optimization of the structural integrity management may reduce the operational expenditures and consequently the LCoE. However, the effect of the structural integrity management on the LCoE is hardly known. To investigate this effect, this paper presents a sensitivity analysis of the LCoE of a generic offshore wind farm. The probabilistic models of the parameters influencing the LCoE are based on a literature study including an explicit model for the structural integrity management. The analysis reveals that LCoE may potentially be reduced if an optimization of the structural integrity management enables a service life extension. T2 - International Probabilistic Workshop 2022 CY - Stellenbosch, South Africa DA - 08.09.2022 KW - Structural integrity management KW - Levelized cost of energy KW - Sensitivity analysis PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-572724 DO - https://doi.org/10.14311/APP.2022.36.0090 VL - 36 SP - 90 EP - 98 PB - Acta Polytechnica CTU Proceedings AN - OPUS4-57272 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Müller, Thoralf T1 - Kurzbericht aus den DIN Ausschüssen N2 - Der Vortrag gibt einen Überblick über die Tätigkeiten der DIN-Ausschüsse "Korrosionsprüfverfahren" sowie "Korrosion und Korrosionsschutz". Es werden neuste Informationen zum Stand verschiedener Normen aus den beiden Ausschüssen gegeben. T2 - Arbeitskreissitzung des GfKorr-Arbeitskreises Korrosionsuntersuchung und -überwachung CY - Leipzig, Germany DA - 21.03.2023 KW - Korrosion KW - Normung KW - Korrosionsprüfung KW - Korrosionsschutz PY - 2023 AN - OPUS4-57243 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bäßler, Ralph T1 - A Coating System for Corrosion Protection of Carbon Steel as an Alternative for High Alloyed Materials N2 - The screening of coatings shows that the modification by adding individual pigment was not sufficient to protect carbon steel even during a short-term exposure, indicated by the discoloration after only seven days of exposure. Electrochemical tests indicated that the coating cathodically protects carbon steel or slows down the corrosion reaction. A long-term exposure test confirmed that the PANI/SiO2 modified coating successfully protects the carbon steel in the Sibayak artificial geothermal water at 150 °C for 6 months. T2 - European Geothermal Congress CY - Berlin, Germany DA - 17.10.22 KW - Corrosion KW - Geothermal KW - Coatings KW - Polyaniniline KW - Silicate PY - 2022 AN - OPUS4-56084 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Aristia, Gabriela A1 - Bäßler, Ralph T1 - A Coating System for Corrosion Protection of Carbon Steel as an Alternative for High Alloyed Materials N2 - Corrosive geothermal brines are a major challenge to geothermal power-plants. For cost reasons, plant designers favorize low alloyed steels, e.g., carbon steel, which are susceptible to uniform and localized corrosion when exposed to geothermal brines having acidic and saline properties. To solve such problem, coatings or inhibitors would be a protective solution as an alternative to the use of high alloyed materials. This study investigated a coating system consisting of polyaniline/silicon dioxide basing on locally available resources. Protection against corrosion of carbon steel is shown by long-term exposure and electrochemical tests of coated carbon steels, performed in an artificial acidic and saline geothermal brine, comparable to real conditions at a site in Indonesia. Therefore, an integrated coating system is presented for corrosion protection, combining the electro-chemical functionality of polyaniline and the physical advantages of silica. T2 - European Geothermal Congress CY - Berlin, Germany DA - 17.10.22 KW - Corrosion KW - Geothermal KW - Coatings KW - Polyaniniline KW - Silicate PY - 2022 SP - 1 EP - 7 CY - Berlin AN - OPUS4-56085 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Tiebe, Carlo T1 - Materialuntersuchungen zur Schadensanalyse an einem explodierten Umlaufkühler N2 - Ein Umlaufkühler ist im Betrieb explodiert. Splitter des zerborstenen Gehäuses aus Kunststoff wurden mit dem Kühlwasser in die Umgebung geschleudert, am Betriebsort entstand Personenschaden. Bei Funktionsprüfungen am beschädigten Gerät traten unerwartet - aber reproduzierbar - Knalleffekte bei Berührung der Außenoberfläche der Kupfer-Kühlschlange auf. Ein möglicher Mechanismus konnte im Labor durch Synthese von Kupferazid auf Kupferproben und Auslösung vergleichbarer Knalleffekte nachgestellt werden. Damit ist die Plausibilität des beschriebenen Schadensereignisses mit diesem oder einem ähnlich reagierenden Stoff belegt. Ein eindeutiger Nachweis darüber, dass bei dem aufgetretenen Schadensfall dieselbe chemische Reaktion stattgefunden hat, war nicht möglich, da die Belag-Überreste aus dem explodierten Kühlgerät für eine Analyse nicht mehr in ausreichender Menge verfügbar gewesen sind. T2 - BG RCI Präventionstagung, Teil 11 - Inkompatible Systeme – Wenn Chemikalien und Werkstoffe heftig reagieren CY - Online meeting DA - 19.01.2022 KW - Explosion KW - Gutachten KW - Kupferazid KW - Materialuntersuchung KW - Schadensanalyse KW - Umlaufkühler PY - 2022 AN - OPUS4-56686 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Gerards-Wünsche, Paul T1 - Der Weg vom Labor zur industriellen Einsetzbarkeit der Risslumineszenz N2 - Der Vortrag beschreibt die Relevanz der Zuverlässigkeitsbewertung von klassischen ZfP- und SHM-Verfahren. Diese Zuverlässigkeitsbewertung soll auch für das an der BAM entwickelte Risslumineszenzverfahren durchgeführt werden. Die Risslumineszenz wird zunächst vorgestellt und es wird beschrieben welchen Weg man beschreiten muss, um eine Zuverlässigkeitsbewertung für eine Technik durchzuführen, die nicht nur als ZfP-Verfahren genutzt werden soll, sondern auch für die Dauerüberwachung unter der Einbindung einer KI-basierten automatisierten Risserkennung. Die mit dieser Erweiterung des Einsatzspektrums einhergehenden Faktoren für Messunsicherheit und -variabilität wird als Problematik erkannt und als zukünftige Aufgabe, die es zu lösen gilt, definiert. T2 - ZfP-Seminar Prof. Große TU München WS22 CY - Online meeting DA - 15.12.2022 KW - Rissprozes KW - Structural Health Monitoring KW - Risslumineszenz KW - Ermüdungsprüfung KW - Rissprozess PY - 2022 AN - OPUS4-56643 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Sadowski, A. A1 - Seidel, M. A1 - Al-Lawati, H. A1 - Azizi, E. A1 - Balscheit, Hagen A1 - Böhm, M. A1 - Chen, Lei A1 - van Dijk, I. A1 - Doerich-Stavridis, C. A1 - Kunle Fajuyitan, O. A1 - Filippidis, A. A1 - Winther Fischer, A. A1 - Fischer, C. A1 - Gerasimidis, S. A1 - Karampour, H. A1 - Kathirkamanathan, L. A1 - Subramanian, S. A1 - Topkaya, Cem A1 - Wagner, H. N. R. A1 - Wang, J. A1 - Wang, J. A1 - Kumar Yadav, K. A1 - Yun, X. A1 - Zhang, P. T1 - 8-MW wind turbine tower computational shell buckling benchmark - Part 1: An international ‘round-robin’ exercise N2 - An assessment of the elastic-plastic buckling limit state for multi-strake wind turbine support towers poses a particular challenge for the modern finite element analyst, who must competently navigate numerous modelling choices related to the tug-of-war between meshing and computational cost, the use of solvers that are robust to highly nonlinear behaviour, the potential for multiple near-simultaneously critical failure locations, the complex issue of imperfection sensitivity and finally the interpretation of the data into a safe and economic design. This paper reports on an international ‘round-robin’ exercise conducted in 2022 aiming to take stock of the computational shell buckling expertise around the world which attracted 29 submissions. Participants were asked to perform analyses of increasing complexity on a standardised benchmark of an 8-MW multi-strake steel wind turbine support tower segment, from a linear elastic stress analysis to a linear bifurcation analysis to a geometrically and materially nonlinear buckling analysis with imperfections. The results are a showcase of the significant shell buckling expertise now available in both industry and academia. This paper is the first of a pair. The second paper presents a detailed reference solution to the benchmark, including an illustration of the Eurocode-compliant calibration of two important imperfection forms. KW - Wind turbine tower KW - Computational KW - Shell buckling KW - Benchmark PY - 2023 DO - https://doi.org/10.1016/j.engfailanal.2023.107124 SN - 1350-6307 VL - 148 SP - 1 EP - 23 PB - Elsevier Science CY - Oxford AN - OPUS4-57019 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Lehmann, Jens T1 - 1. Sitzung GfKORR AK "Atmosphärische Korrosion" N2 - Eine Übersicht zu den Zielen und Schwerpunktthemen des neu gegründeten Arbeitskreises Atmosphärische Korrosion. T2 - 1. Sitzung des GfKORR Arbeitskreises Atmosphärische Korrosion CY - Online meeting DA - 25.01.2023 KW - Korrosion KW - Atmosphäre KW - Luftqualität KW - Auslagerungsversuche PY - 2023 AN - OPUS4-57022 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Zhang, Kun A1 - Pan, L. A1 - Li, J. A1 - Lin, C. T1 - What is the mechanism of the fiber effect on the rheological behavior of cement paste with polycarboxylate superplasticizer? N2 - Compared with most common construction materials, fiber reinforced cementitious materials are well known to exhibit better physical, working and mechanical properties. In this study, three fibers were selected: polypropylene fiber (PPF) and polyvinyl alcohol fiber (PVAF), which represented synthetic fibers, and sisal fiber (SF), which represented natural fibers. Effects of these fibers on the flowability, rheological properties, and adsorption behavior of the cement paste with polycarboxylate superplasticizer (PCE) were investigated. Furthermore, the above experimental results were verified by measuring the contact angle of the fiber with water and PCE solution and the apparent morphology of the fiber. Results revealed that the addition of fibers significantly reduces the fluidity of the cement paste, while the yield stress and plastic viscosity of the cement paste increase with the addition of fibers. From the contact angle and scanning electron microscope, the surface of SF was relatively rough, and the contact angle of SF with water or PCE solution was the smallest. It can be concluded that the plant fiber has a significant influence on the fluidity and rheology of cement paste. KW - Cement paste KW - Polycarboxylate superplasticizer KW - Polypropylene fiber KW - Polyvinyl alcohol fiber KW - Sisal fiber KW - Rheological property KW - Fluidity KW - Adsorption PY - 2021 DO - https://doi.org/10.1016/j.conbuildmat.2021.122542 SN - 0950-0618 VL - 281 SP - 1 EP - 11 PB - Elsevier CY - Amsterdam AN - OPUS4-56893 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Lehmann, Jens T1 - VORSTELLUNG DES NEUEN GFKORR ARBEITSKREISES „ATMOSPHÄRISCHE KORROSION“ N2 - In diesem Vortrag wird ein Überblick über die Themen und Schwerpunkte des Arbeitskreises Atmosphärische Korrosion gegeben. Dabei werden einige Beispiele für relevante Fragestellungen aufgegriffen. T2 - Sitzung des GfKORR AK Eisen und Stahl CY - Online meeting DA - 08.12.2022 KW - Korrosion KW - Atmosphäre KW - Luftqualität KW - Auslagerungsversuche PY - 2022 AN - OPUS4-56546 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schartel, Bernhard T1 - Flammschutz trifft geklebte Verbindungen N2 - Produkte, Bauteile und Konstruktionen im Transport- und Bauwesen bestehen mehr und mehr aus Klebverbunden. Allein die Menge des verwendeten Klebstoffes oder die Anzahl geklebter Verbindungen schließen für eine verlässliche Betrachtung und Bewertung der Brandrisiken aus, deren Beitrag zur Brandentstehung, Flammenausbreitung oder Feuerwiderstand von Baugruppen und Konstruktionen zu vernachlässigen. Anforderungen an die Leistungsbeschreibungen von flammgeschützten Klebstoffen bzw. Haftklebebändern werden definiert, oft ohne ein ausreichendes Verständnis der Beiträge von Klebverbunden zum Brandverhalten der Bauteile zu haben. Der Vortrag beleuchtet diese Problematik und stellt die verschiedenen komplexen Anforderungen aus dem Brandschutz in Hinblick auf Auswahlkriterien und Entwicklungsziele für flammgeschützte Klebstoffe dar. Dabei ist dieser Transfer des Brandverhaltens, sprich der Systemantwort einer Komponente oder Bauteils in einem spezifischen Brandszenario, in Materialeigenschaften des Klebstoffes eine intrinsische und anspruchsvolle Herausforderung. Im abgeschlossenen IGF-Projekt Nr. 20762 N (Forschungsvereinigung DECHEMA) haben wir für Klebebänder eine systematisch-wissenschaftliche Studie durchgeführt und aussagekräftige Erkenntnisse zu Verfügung gestellt. Die Untersuchungen zur Entflammbarkeit zu Brandbeginn, zur Flammenausbreitung (Wärmeentwicklung) im sich entwickelnden Brand und zum Feuerwiderstand im Vollbrand machen die sehr unterschiedlichen Einflüsse von Klebverbunden, d. h. auch die unterschiedlichen Anforderungen an die Modifikation der Klebebänder, deutlich. Die thermische Analyse verschiedener Klebstoffe zusammen mit den Brandtest freistehender Haftklebebänder, an einseitig geklebten Substraten und an Klebverbundprobekörpern skizzieren eindrucksvoll die komplexen Zusammenhänge zwischen Materialeigenschaften der Klebebänder und dem Brandverhalten von Klebverbunden. Der Vergleich von verschiedenen Substraten wie Stahlbleche, Holz, Mineralwolle und verschiedene Polymermaterialien belegt darüber hinaus, dass der Einfluss der Klebverbindungen auf das Brandverhalten der Klebverbunde substratspezifisch ist. Gerade der Vergleich zwischen Holz, Polymethylmethacrylat (PMMA) und Bisphenol A Polycarbonat (PC) liefert überraschend unterschiedliche Ergebnisse. Die Variation der Klebstoffe und Trägermaterialien der Klebebänder skizziert die verschiedenen Möglichkeiten für die Materialentwicklung. Abhängig vom Material und Brandszenario können Klebverbunde im Vergleich zu gleich dicken Probekörpern aus demselben Substrat sowohl eine deutliche Erhöhung der Brandrisiken, ein praktisch unverändertes Brandverhalten oder eine Reduktion des Brandrisikos hervorrufen. Grundsätzlich kann keine Lösung bzw. kein Tape gefunden werden, die mit allen Substraten einen guten Brandschutz gewährleistet. Substrate, Carrier und Klebstoff müssen nicht nur aufeinander abgestimmt werden, sondern auch auf das Brandszenario, in welchem der Verbund eine gute Performance liefern soll.Das IGF-Projekt (20762) der Forschungsgemeinschaft (DECHEMA Deutsche Gesellschaft für Chemische Technik und Biotechnologie e V, Theodor Heuss Allee 25, 60486 Frankfurt am Main) wurde durch die AiF im Rahmen des Programms „Förderung der Industriellen Gemeinschaftsforschung (IGF)” des Bundesministeriums für Wirtschaft und Klimaschutz aufgrund eines Beschlusses des Deutschen Bundestages gefördert. T2 - 23. Kolloquium Gemeinsame Forschung in der Klebtechnik CY - Frankfurt am Main, Germany DA - 28.02.2023 KW - Klebebänder KW - Entflammbarkeit KW - Brandverhalten KW - Feuerwiderstand KW - Flammschutz PY - 2023 AN - OPUS4-57073 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kühne, Hans-Carsten A1 - Hüsken, Götz A1 - Mundra, Shishir A1 - Sander, C. A1 - Obermann, S. T1 - Die Betondickglasfenster des Glockenturms am Eiermannbau der Kaiser-Wilhelm-Gedächtniskirche N2 - Die Kaiser-Wilhelm-Gedächtniskirche (KWG) gilt als eine der wichtigsten Sehenswürdigkeiten Berlins in der City West und als ein herausragendes Beispiel für die „Dalle de Verre“ Verglasungen in sakralen Gebäuden. Der vorliegende Beitrag widmet sich der Fassade und den Glasfenstern des neuen Glockenturms, wobei die beschriebenen Szenarien aufgrund der annähernd gleichen Bauweise der restlichen neuen Baukörper in weiten Teilen starke Analogien aufweisen und insofern übertragbar sind. T2 - Workshop Kulturguterhaltung - Vom Dampfkessel zu Nanomaterialien CY - Berlin, Germany DA - 17.11.2021 KW - Kaiser-Wilhelm-Gedächtniskirche KW - Betondickglasfenster KW - Instandsetzung KW - Elektrochemische Realkalisierung PY - 2021 VL - 3 SP - 125 EP - 140 PB - Druckerei G. Bohm CY - Berlin AN - OPUS4-57092 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Chan, Yin Yam A1 - Korwitz, A. A1 - Pospiech, D. A1 - Schartel, Bernhard T1 - Flame Retardant Combinations with Expandable Graphite/ Phosphorus/CuO/Castor Oil in Flexible Polyurethane Foams N2 - A series of flexible polyurethane foams (FPUFs) were prepared with single and different combinations of flame retardants and additives. Expandable graphite (EG), phosphorous polyol (OP), copper (II) oxide (CuO), and/or castor oil (CAS) were added to FPUF during the foam preparation in a one-step process. The purpose of the study is to evaluate the synergistic effects of the flame retardants, additives, and the presence of bio-based content on the mechanical properties, flame retardancy, and smoke behavior of FPUFs. The combination of 10 wt % EG and 5 wt % OP in FPUF significantly improves the char yield. In the cone calorimeter experiment, the char yield is nearly three times higher than that with 10 wt % EG alone. The smoke behavior is additionally evaluated in a smoke density chamber (SDC). Comparing the samples with a single flame retardant, 10 wt % EG in FPUF considerably reduces the amount of smoke released and the emission of toxic gases. Replacing the amount of 10 wt % polyether polyol in FPUF with CAS maintains the physical and mechanical properties and fire behavior and enhances the bio-based content. The presence of 0.1 wt % CuO in FPUF effectively reduces the emission of hydrogen cyanide. As a result, this study proposes a multicomponent flame retardant strategy for FPUF to enhance the biomass content and address the weaknesses in flame retardancy, smoke, and toxic gas emissions. A starting point is disclosed for future product development. KW - Flexible polyurethane foam KW - Flame retardancy KW - Synergistic effect KW - Smoke behavior KW - Expandable graphite KW - Bio-based PY - 2023 DO - https://doi.org/10.1021/acsapm.2c01969 SN - 2637-6105 VL - 5 IS - 3 SP - 1891 EP - 1901 PB - ACS AN - OPUS4-57507 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schartel, Bernhard T1 - Flame retardant biocomposites: Up-and-coming N2 - - biocomposite (=biopolymer/natural fibres) replacing technical polymers - renewable building blocks for flame retardants - exploiting waste streams for sustainable adjuvants and flame retardants - bio-vitrimers T2 - 1st Conference - Flame Retardancy for Composite Applications in the Transport Sector CY - Berlin, Germany DA - 10.05.2023 KW - Biocomposite KW - Flame retardant KW - Vitrimer KW - Renewable KW - Sustainable PY - 2023 AN - OPUS4-57511 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Řepka, Jakub A1 - Vlach, Tomáš A1 - Hájek, Jakub A1 - Fürst, Richard A1 - Pošta, Jan A1 - Hájek, Petr T1 - Woven Carbon-Fiber-Reinforced Polymer Tubular Mesh Reinforcement of Hollow High-Performance Concrete Beams N2 - This article presents woven carbon-fiber-reinforced polymer (CFRP) tubular mesh used as a reinforcement on the inner surface of hollow beams made of high-performance concrete (HPC). The tubular mesh was designed to serve as both the tensile and shear reinforcement of hollow beams intended for the construction of small self-supporting structures that could be assembled without mechanization. The reinforcement was prepared with a tri-axial weaving machine from carbon filament yarn and was homogenized using epoxy resin. The interaction of the composite reinforcement with the cementitious matrix was investigated, and the surface of the reinforcement was modified using silica sand and polyvinyl alcohol (PVA) fibers to improve cohesion. The sand coating enhanced bond strength, resulting in the significantly higher flexural strength of the hollow beam of 128%. The PVA fibers had a lower positive effect of 64% on the flexural strength but improved the ductility of the beam. Individual beams were connected by gluing steel parts directly inside the hollow core of the HPC beam. This procedure provides good interaction between the CFRP reinforcement and the glued steel insert and allows for the fast and simple assembly of structures. The weaving of additional layers of the CFRP reinforcement around HPC beams was also explored. A small structure made of the hollow HPC beams with inner composite reinforcement was constructed to demonstrate the possibilities of the presented technology. KW - Carbon-fiber-reinforced polymer KW - Woven composite reinforcement KW - Hollow concrete beams KW - High-performance concrete KW - Bond strength KW - Sand-coated KW - PVA fibers PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-607586 DO - https://doi.org/10.3390/polym15143089 VL - 15 IS - 14 SP - 1 EP - 15 PB - MDPI AG AN - OPUS4-60758 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Giv, Ali Nemati A1 - Asante, Bright A1 - Yan, Libo A1 - Kasal, Bohumil T1 - Shear performance and durability of adhesively bonded spruce wood-concrete composite joints: Effects of indoor and outdoor environmental conditions, mechanical load, and their coupled effect N2 - A long-term study was conducted on double-lap spruce wood-concrete joints to investigate their shear strength and stiffness over a 12-month period. These joints were manufactured using both wet and dry processes, each incorporating two adhesive types for bonding the wood to the concrete: a brittle epoxy and a ductile polyurethane (PUR). The experimental design exposed the joints to three specific long-term environments: (1) outdoor exposure, (2) indoor conditions with applied load, and (3) outdoor conditions with applied load. The wood concrete joints exposed to outdoor conditions were subjected to destructive shear testing at intervals of 0 (serving as the reference sample), 2, 4, 6, and 12 months, respectively. For joints subjected to both indoor and outdoor conditions with shear loading, the shear deformation of joints was monitored continuously over the 12 months before performing the destructive tests. A gradual reduction in the shear stiffness and strength of dry joints (produced using the dry bond method) exposed to outdoor conditions was observed over a 12-month period, primarily due to bond failure at the concrete-adhesive interface. The wet joints exhibited no degradation in shear stiffness and strength across long-term conditions over the same period. The bond failure observed in dry joints was predominantly associated with stresses arising from dimensional changes in the wood. No degradation was found in the cross-linking density of the adhesive or in the concrete’s compressive stiffness and strength. KW - Adhesively bonded joints KW - Long-term study KW - Ductile PUR KW - Brittle epoxy KW - Outdoor condition KW - Mechanical load KW - Indoor condition PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-608878 DO - https://doi.org/10.1016/j.conbuildmat.2024.136905 VL - 436 SP - 1 EP - 22 PB - Elsevier BV AN - OPUS4-60887 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schartel, Bernhard T1 - Thermal Decomposition Features Flame Retardancy N2 - INTRODUCTION: Most polymeric materials in most fire scenarios burn based on an anaerobe pyrolysis feeding the flame with fuel. Understanding the thermal decomposition in the condensed phase is key to tailor flame retardancy. Adjusting the decomposition temperature of flame retardant and polymer as well as providing the desired chemical structure for specific reactions determine the molecular mechanisms and thus the flame-retardant modes of action. Hereby, it is not only charring in the condensed phase and radical scavenging in the gas phase, but also physicochemical and physical effects such as melt flow and protective layer formation. This paper delivers thought-provoking impulses on how the understanding of the pyrolysis can be used for evidenced-based development and optimization of flame-retardant polymeric materials. Some rather overseen details are picked up as well as rethinking of concepts memorized long ago is encouraged to discover something new. The talk tries to fill some gaps between flame-retardant mechanisms, flame-retardant modes of action, and fire performance. EXPERIMENTAL: Materials - This paper deduces its conclusions from results of several research projects performed in the working group of the author. For a detailed description of the materials, their compounding, and the preparation of test specimens please go for the comprehensive description in the original papers.[1-10] Methods - A multi-methodical approach based on thermogravimetry (TGA), TGA coupled with evolved gas analysis (TGA-FTIR), hot stage FTIR, pyrolysis GC/MS, and residue analysis was used for investigating the pyrolysis. The flammability in the fire scenario ignition was addressed using oxygen index (OI) and testing in the UL 94 burning chamber. The fire behaviour in developing fires was investigated using a cone calorimeter. Additional efforts complete the studies, such as other fire tests, advanced analysis of the fire residue, melt rheology, or particle finite element simulations (PFEM). Tailored and self-designed experiments and advanced data evaluation described fire phenomena or modes of action. For a detailed description of the experimental the reader is relegated to the original papers.[1-10] RESULTS AND DISCUSSION: One important aspect in achieving, adjusting, and optimising flame retardancy is exploiting specific chemical reactions in the condensed phase between the pyrolyzing polymer and the flame retardant at the right place, time, and temperature.[1-3] At the same time, these reactions of partly decomposed or hydrolysed flame retardants in the condensed phase competes with releasing as volatile into the gas phase. Based on three comparisons this field is illuminated in detail: reactive phosphine oxide, phosphinate, phosphonate, and phosphate are compared in the same epoxy resins evaluating the influence of the oxidation state,[1] different phosphorous flame retardants in different epoxy resins underlining the specific reactions between the partly decomposed or hydrolysed flame retardant and the partly decomposed polymer,[3] and the comparison of three aryl phosphates with different volatility highlights the competition of chemical reaction in the condensed phase and gasification.[2] Any fire residue reduces fire risks, when the release of hydrocarbon fuel into the gas phase is replaced by storing fuel in the condensed phase as carbonaceous char. Thus, charring describing crosslinking, dehydration, aromatization, and graphitization is the flame retardancy mechanisms, whereas charring describing the reduction in fire load the flame-retardant mode of action. The phenomenon charring belongs to a complete pyrolysis or complete pyrolysis step; the char yield indicates the amount of fuel stored in the residue. Further, any fire residue works as protective layer. The barrier properties depend on the physical properties of the residue but not necessarily on its amount.[4] Usually, a residue design such as a tailored morphology of the fire residue is demanded. The mass loss rate and heat release rate are reduced. The main mechanisms are heat shielding and thermal insulation.[5] Sometimes the protective layer is good enough to cause incomplete pyrolysis due to extinguishing before the pyrolysis front went through the whole sample.[6.7] Analogous to charring also incomplete pyrolysis can result in efficient reduction in fire load. Proper data evaluation and key experiments are used to sort out and understand these different phenomena. Flame retardant polyurethane foams passing the heat release and smoke toxicity requirements of EN 45545 are discussed as evidence-based development using charring and incomplete pyrolysis due to an efficient protective layer.[7,8] The thermal decomposition into liquid intermediate products increases crucially the melt flow during burning,[9] whereas charring and the ablation of the polymer matrix increasing the content of fillers yield melt viscosities enlarged by orders of magnitude.[10] Violent burning of some polymers at the end of a cone calorimeter test can be understood as pyrolysis enabling a pool fire. The understanding of the thermal decomposition of the polymeric material harbours the explanation of non-flaming dripping extinguishing the flame via sufficient cooling, retreat effects preventing ignition, and efficient nondripping flame retardancy. This paper leads the audience from chemistry over complex macroscopic fire phenomena of physicochemical nature to fire performance. Thought-provoking impulses are given how the scientific understanding of the pyrolysis in the condensed phase can be used for research and evidenced-based development of future flame-retardant polymeric materials. Acknowledgement: The talk uses results from distinct projects; thus, thanks go to the German Research Foundation DFG SCHA 730/6-1, SCHA 730/8, SCHA 730/10-1, and Scha 730/19-1, Bayer MaterialScience AG, and the BMWi (BMWK) AiF: IGF No.: 19078 N/2 for financial support. Many thanks to former working group members U. Braun, Y. Y. Chan, B. Perret, S. Rabe, K. H. Richter, A. Weiß, and G. Wu, and to our co-operation partners A. Hartwig (IFAM), M. Döring and M. Ciesielski (at that time KIT), and J. M. Marti (CIMNE) as well. T2 - 11th Conference of the Modification, Degradation, Stabilization of Polymers, MoDeSt 2024 CY - Palermo, Italy DA - 01.09.2024 KW - Flame retardants KW - Decomposition KW - Modes of action KW - Mechanisms KW - Charring KW - Flame inhibition KW - Dripping KW - Protective layer KW - Pyrolysis PY - 2024 AN - OPUS4-60960 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Silvestro, L. A1 - Ruviaro, A. S. A1 - Lima, G. A1 - Durlo Tambara, Luis Urbano A1 - Feys, D. A1 - Kirchheim, A. P. T1 - Rotational rheometry test of Portland cement-based materials - A systematic literature review N2 - This study systematically reviews 62 papers on the use of rotational rheometry to assess the fresh state behavior of Portland cement-based materials. The research highlights the wide variation in test methods and aims to provide a comprehensive overview. Findings reveal that 50.0% of studies employed vane geometry, despite its limitations in providing transformation equations. Regarding dynamic shearing tests, 67.0% followed a consensus using a pre-shearing step and a step-wise routine with stabilization times ≥ 10 s. While the Bingham model is commonly used, the study emphasizes the importance of considering shear-thinning behavior in cementitious materials. Models like Herschel-Bulkley and modified Bingham may be more appropriate. This review offers insights into testing conditions for rotational rheometry of cementitious materials, serving as a foundation for future research in the field. KW - Review KW - Rheology KW - Rheometry KW - Rotational KW - Cement PY - 2024 DO - https://doi.org/10.1016/j.conbuildmat.2024.136667 SN - 0950-0618 VL - 432 SP - 1 EP - 14 PB - Elsevier Ltd. CY - Amsterdam AN - OPUS4-60075 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Chacon Castro, Jose Pablo A1 - Schneider, Rika A1 - Greiner, Andreas A1 - Schartel, Bernhard T1 - Flame retardant poly(limonene carbonate): material innovation as a game changer N2 - The global plastic industry relies on fossil-based materials, presenting environmental challenges. A sustainable polymer namely poly(limonene carbonate) (PLimC), made of limonene and CO2 as two monomers from non-food sources, shows advances in various applications where additives such as flame retardants (FRs) are crucial to comply with fire safety measures. The variety of FRs is wide, and therefore the approach involved conducting a comparative study of four different halogen-free flame retardant systems that are conventionally used in polycarbonates and polyolefins to understand which FR enhances the flame resistance of PLimC most effectively. The primary task of the project is to conduct experimental evaluations to analyze the thermal properties, flammability, and fire behavior of each system. This data will offer valuable insights towards the advancement of safer and more sustainable materials. T2 - Polymers for Sustainable Future 2024 CY - Prague, Czech Republic DA - 24.06.2024 KW - Poly(limonene carbonate) KW - Flame retardancy KW - Fire science PY - 2024 AN - OPUS4-60556 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Sunder, S. A1 - Jauregui Rozo, Maria A1 - Inasu, S. A1 - Schartel, Bernhard A1 - Ruckdäschel, H. T1 - A systematic investigation of the transfer of polyphosphate/inorganic silicate flame retardants from epoxy resins to layered glass fiber-reinforced composites and their post-furnace flexural properties N2 - The systematic transfer of solvent-free, additive flame retardant (FR) formulations from epoxy resins to glass fiber-reinforced epoxy composites (GFRECs) through prepregs is difficult. Additionally, obtaining data on their post-fire mechanics is often challenging. Utilizing melamine polyphosphate (MPP), ammonium polyphosphate (APP), and silane-coated ammonium polyphosphate (SiAPP) FRs with low-melting inorganic silicates (InSi) in an 8:2 proportion and 10% loading by weight in a diglycidyl ether of bisphenol A (DGEBA) resin, a systematic investigation of the processing properties, room-temperature mechanics, and temperature-based mechanics of the systems was performed. The resin was cured with a dicyandiamide hardener (DICY) and a urone accelerator. The results revealed no substantial impact of these FRs at the current loading on the resin's glass transition temperature or processability. However, the fire residues from cone calorimetry tests of the composites containing FRs were found to be only 15-20% of the thickness of the resins, implying a suppression of intumescence upon transfer. At room temperature, the decrease in the flexural modulus for the composites containing FRs was negligible. Exposure of the composites in a furnace at 400°C as a preliminary study before ignition tests was shown to cause significant flexural moduli reductions after 2.5 min of exposure and complete delamination after 3 min making further testing unviable. This study emphasizes the need for future research on recovering modes of action upon transfer of FR formulations from resins to composites. Based on the challenges outlined in this investigation, sample adaptation methods for post-fire analysis will be developed in a future study. KW - DGEBA KW - Prepregs KW - Glass fiber-reinforced composites KW - Post-fire testing PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-605239 DO - https://doi.org/10.1002/pc.28416 SN - 1548-0569 SN - 0272-8397 VL - 45 IS - 10 SP - 9389 EP - 9406 PB - Wiley AN - OPUS4-60523 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Rockel, Daniel A1 - Sanchez Olivares, G. A1 - Schartel, Bernhard T1 - Improving the Flame Retardancy of Aluminium Trihydroxide in Thermoplastic Starch Biocomposites Using Waste Fibers and Silicon-Based Synergists N2 - The synergistic behavior of different silicon compounds is investigated in flame retardant biocomposites with aluminum trihydroxide (ATH) as the main flame retardant. The paper shows a new approach towards sustainable biocomposites through the implementation of thermoplastic starch (TPS), leather fibers from industrial waste streams, and non-hazardous flame retardants and synergists. In these multicomponent systems, the different components address different modes of action in the fire scenario. When ATH is partially substituted by glass frits or layered silicates, fire performance is enhanced without changing the total amount of filler in the polymer. In a biocomposite with 25 phr of fiber and 90 phr of ATH, substituting 5 phr of ATH for layered silicates increased the LOI from 31.5 vol % to 34.8 vol %, decreased the peak of heat release by 20%, and increased the UL 94 rating from V-1 to V-0. KW - Biocomposites KW - Sustainability KW - Waste streams KW - Flame retardancy KW - Synergism KW - Modes of action PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-605711 DO - https://doi.org/10.1021/acssusresmgt.4c00053 SN - 2837-1445 VL - 1 IS - 6 SP - 1131 EP - 1145 PB - ACS AN - OPUS4-60571 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sunder, Sruthi T1 - Investigating the trade-off effects of inorganic phosphate/silicate flame retardant (FR) content on the fire performance and post fire flexural mechanics of epoxy/glass fiber composites N2 - Considering the existing challenges involved in the transfer of flame retardant (FR) formulations from epoxy (EP) resins to glass fiber reinforced composites (GFRCs), obtaining data on the post-fire flexural properties of such composites is even more challenging as this involves balancing test parameters with potential composite delamination. In this study, solvent-free FR additives: ammonium polyphosphate (APP), and inorganic silicate (InSi) were added at 10, 30% and 50% w/w loading to a Bisphenol A diglycidyl ether (DGEBA)-dicyandiamide (DICY)-Urone resin matrix. These resin formulations were transferred to bidirectional (BD) glass fiber composites via prepregs. A novel, but facile approach was developed to prepare the composite samples for furnace tests at 400 oC. The composites were also subjected to fire exposure at different heat fluxes and times via a bench-scale test and subsequently tested via three-point bending. At approximately 3.5% P content, the FRs significantly improve the fire performance of both the resins and composites. However, they also degrade the systems’ pre- and postfire flexural modulus and strength. Therefore, improving the flame-retardant mode of action of the FRs in the composites, contrastingly reduces their structural integrity post-fire leading to a trade-off effect. T2 - ECCM21 – 21st European Conference on Composite Materials CY - Nantes, France DA - 02.07.2024 KW - Flame retardants KW - Post-fire KW - Epoxy KW - Glass fiber composites KW - Prepregs PY - 2024 AN - OPUS4-60795 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Sunder, S. A1 - Jauregui Rozo, Maria A1 - Inasu, S. A1 - Schartel, Bernhard A1 - Ruckdäschel, H. T1 - Investigating the changing dynamics of processing, temperature-based mechanics, and flame retardancy in the transfer of ammonium polyphosphate/inorganic silicate flame retardants from epoxy resins to glass fiber composites N2 - Although numerous investigations study the improvement of flame retardancy of epoxy resins using additives, maintaining the flame retardant (FRs) modes of action present in the resins upon transfer to composites is challenging. In this study, ammonium polyphosphate (APP) and inorganic silicate (InSi) are loaded at 10%, 30%, and 50% by weight, in a diglycidyl ether of bisphenol A (DGEBA) resin cured with dicyandiamide and transferred to bidirectional (BD) glass fiber (GF) composites. Although a 50% loading of the FRs impacts the curing kinetics of the resin system, the effect on the glass transition temperature of the resin system remains negligible compared to reactive FRs in the state of the art integrated into the resin's chemical structure. Increasing the FR content improved the heat release characteristics in both the resins and composites. However, the charring mode of action is completely suppressed in the formulation with 10% APP + InSi. A 30% concentration of the FRs restored the charring action in the composite and the GFs provide increased protective layer action upon transfer to the composites. This study highlights the importance of accounting for the changing dynamics related to processing and flame retardancy upon transferring FRs from resins to composites. KW - Composites KW - Flame retardance KW - Resins KW - Synthesis and processing techniques PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-610484 DO - https://doi.org/10.1002/app.55988 SN - 1097-4628 VL - 141 IS - 39 SP - 1 EP - 18 PB - Wiley CY - New York, NY AN - OPUS4-61048 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CHAP A1 - Schartel, Bernhard ED - Morgan, A. B. ED - Wilkie, C. A. T1 - Multi-Component Flame-Retardant Systems N2 - Applying synergistic multicomponent systems is often key to efficient flame retardancy. Different flame retardants are combined or used together with fillers, adjuvants, or synergists to enhance their efficiency, reduce the worsening of other properties, or reduce the costs. Further, fibres and other reinforcing fillers contribute to fire properties crucially. Although the main flame-retardant modes of action are known, the scientific understanding usually falls short, when it comes to complex multicomponent systems, the crucial tiny optimizations, or quantifying in terms of specific fire properties. This book chapter illuminates the need for the multicomponent approach, the concept of synergistic flame retardants, and the main phenomena. Multicomponent systems are discussed in their capacity as general powerful strategy for achieving and optimizing future flame retardant polymeric materials. KW - Flame retardants KW - Flame retardancy KW - Synergy KW - Composites PY - 2024 SN - 978-1-0324-5754-3 SN - 978-1-0324-6233-2 SN - 978-1-0033-8068-9 DO - https://doi.org/10.1201/9781003380689 SP - 330 EP - 359 PB - CRC Press CY - Boca Raton ET - 3rd AN - OPUS4-60843 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CHAP A1 - Schartel, Bernhard ED - Morgan, A. B. ED - Wilkie, C. A. T1 - Uses of Fire Tests for Flame-Retardant Material Development N2 - Innovation and scientific progress are often located in the synthesis of new flame retardants or in the compounding of new composites. Thus, although nearly everyone applies fire tests to ascertain the flame retardancy achieved, regular, cost-efficient fire testing is preferred, sometimes its reliability and meaningfulness are questioned. The goal of this revised chapter is to inspire the exploitation of the potential of fire testing beyond a soulless pass-and-fail or isolated number rating. Recommendations are given as to how fire behaviour can be investigated and how data can be evaluated faithfully and meaningfully. Backgrounds and benchmarks are discussed as thought-provoking impulses which could allow bench-scale fire testing to be exploited as a vital basis and powerful tool for science-based development. KW - Fire behaviour KW - Flammability KW - Flame retardancy KW - Flame retardant modes of action KW - Flame retardants KW - Fire scenarios KW - Ignition KW - Developing fire KW - Fire tests KW - Cone calorimeter KW - Petrella plot PY - 2024 SN - 978-1-0324-5754-3 SN - 978-1-0324-6233-2 SN - 978-1-0033-8068-9 DO - https://doi.org/10.1201/9781003380689-17 SP - 360 EP - 385 PB - CRC Press CY - Boca Raton ET - 3rd AN - OPUS4-60845 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sunder, Sruthi A1 - Jauregui Rozo, Maria A1 - Ruckdäschel, Holger A1 - Schartel, Bernhard T1 - Investigating the trade-off effects of inorganic phosphate/silicate flame retardant content on the fire performance and post-fire flexural mechanics of epoxy/glass fiber composites N2 - Considering the existing challenges involved in the transfer of flame retardant (FR) formulations from epoxy (EP) resins to glass fiber reinforced composites (GFRCs), obtaining data on the post-fire flexural properties of such composites is even more challenging as this involves balancing test parameters with potential composite delamination. In this study, solvent-free FR additives: ammonium polyphosphate (APP), and inorganic silicate (InSi) were added at 10, 30% and 50% w/w loading to a Bisphenol A diglycidyl ether (DGEBA)-dicyandiamide (DICY)-Urone resin matrix. These resin formulations were transferred to bidirectional (BD) glass fiber composites via prepregs. A novel, but facile approach was developed to prepare the composite samples for furnace tests at 400 oC. The composites were also subjected to fire exposure at different heat fluxes and times via a bench-scale test and subsequently tested via three-point bending. At approximately 3.5% P content, the FRs significantly improve the fire performance of both the resins and composites. However, they also degrade the systems’ pre- and postfire flexural modulus and strength. Therefore, improving the flame-retardant mode of action of the FRs in the composites, contrastingly reduces their structural integrity post-fire leading to a trade-off effect. T2 - ECCM21 – 21st European Conference on Composite Materials CY - Nantes, France DA - 02.07.2024 KW - Flame retardants KW - Post-fire KW - Epoxy KW - Glass fiber composites KW - Prepregs PY - 2024 SP - 1 EP - 7 AN - OPUS4-60788 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sunder, Sruthi A1 - Jauregui Rozo, Maria A1 - Ruckdäschel, Holger A1 - Schartel, Bernhard T1 - Adapting intumescent/low-melting glass flame-retardant formulations for transfer to glass-fiber-reinforced composites and postfiremechanical analysis N2 - The residual post-fire mechanical properties of fiber-reinforced epoxy (EP) composites are influenced by their fire residues after burning. This study uses intumescent/low-melting glass flame retardants (FRs) to tailor fire residues in epoxy resin. Processibility of prepregs, and their quality are analysed for transfer of the flame-retardant epoxy resins to layered glass-fiber reinforced composites (GFRCs). Minimal effects were found on the pre-fire flexural strengths of the composites due to low loading of the FRs. However, when transferred to GFRCS, the fire residues diminish significantly. Process, testing, and material adaptations are required to improve theoretical and experimental estimations of the post-fire mechanics of the composites. T2 - SAMPE Europe Conference 2023 Madrid - Spain CY - Madrid, Spain DA - 03.10.2023 KW - Fire residue KW - Prepregs KW - Mechanics PY - 2023 AN - OPUS4-60789 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Jauregui Rozo, Maria A1 - Sunder, Sruthi A1 - Ruckdäschel, Holger A1 - Schartel, Bernhard T1 - Weaving Through Fire And Force: Fire Behavior and Modes of Action between Epoxy Resin and Glass Fiber Composites N2 - This project aims to investigate the fire behavior, fire stability, and modes of action in flame retardancy of phosphorus-based flame-retardant polymeric materials in fiber-reinforced composites and compare them to epoxy resins. T2 - BASF International Summer Course 2024 CY - Ludwigshafen, Germany DA - 04.08.2024 KW - Flame retardants KW - Fire behavior KW - Fire stability PY - 2024 AN - OPUS4-60790 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Fürst, Richard T1 - Behaviour of textile-reinforced concrete structures at elevated temperatures N2 - Presentation of the dissertation thesis about textile-reinforced concrete structures at elevated temperatures. The presentation at the conference was requested as a part of the award ceremony for the best dissertation thesis within the WTA Young Professional Awards. T2 - WTA Days 2024 CY - Brünn, Czech Republic DA - 14.03.2024 KW - Textile-reinforced concrete KW - Fire KW - Fire resistance KW - HPC KW - Epoxy resin PY - 2024 AN - OPUS4-60812 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Häßler, Dustin A1 - Becker, Andreas A1 - Fürst, Richard A1 - Hothan, Sascha ED - Simões da Silva, Luís ED - Vila Real, Paulo ED - Santiago, Aldina ED - Craveiro, Hélder ED - Laim, Luís T1 - Fire resistance testing of steel tension members with hollow section protected by intumescent coating N2 - This book presents the proceedings of the Thirteenth International Conference Structures in Fire. The conference took place at the Department of Civil Engineering, University of Coimbra, Portugal, from 19 to 21 June 2024, under the auspices of the SIF movement. Structural fire safety is a crucial aspect of the design of buildings and infrastructures. Significant advances in research have increased the knowledge on this topic. However, until the 1990s, there were few forums for structural fire engineers to exchange ideas and share research findings. SIF (Structures in Fire) specialised workshop series was conceived in the late 1990s and the “First International SIF Workshop” was held in Copenhagen, Denmark in 2000, followed by workshops in Christchurch, New Zealand (2002), Ottawa, Canada (2004) and Aveiro, Portugal (2006). The series of workshops evolved into conferences and the 2008 event in Singapore was the fifth International Conference on Structures in Fire. This was followed by events in East Lansing, USA (2010), Zurich, Switzerland (2012), Shanghai, China (2014), New Jersey, USA (2016), Belfast, UK (2018), Brisbane, Australia (2020) and Hong Kong, China (2022). Information about previous conferences, including complete proceedings, can be found at www.structuresinfire.com. The main mission of SIF conferences is to provide an opportunity for researchers and engineers from the global structural fire engineering community to participate, share and discuss the recent findings, innovations and developments with their peers in an open and international forum. Following the great success of the previous International Conferences, the University of Coimbra was selected to host the 13th International Conference on Structures in Fire. As with most of the recent conferences, the number of papers submitted far exceeds the number of papers that can be accommodated in the three-day programme, even with two parallel sessions. SIF 2024 received 249 abstracts before the deadline and accepted 172 abstracts after the review process by at least three reviewers from the scientific committee. These proceedings represent 132 full papers, collectively representing the state of the art in fundamental knowledge and practical application of structures in fire. Forty-two countries from around the globe have contributed to them. The papers are grouped into the following research topics: Applications of Structural Fire Engineering, Composite Structures in Fire, Concrete Structures in Fire, Timber Structures in Fire, Masonry Structures in Fire, Steel Structures in Fire, Experimental Research of Structures in Fire, Numerical Modelling of Structures in Fire, Other Topics Related to Structures in Fire. Finally, the Organizing Committee would like to thank the continuous support from the SIF Steering Committee chaired by Prof Jean-Marc Franssen. We also would like to thank to the Scientific Committee chaired by Prof Paulo Vila Real, the authors and all the supporting staff (and volunteer team) from the Institute for Sustainability and Innovation in Structural Engineering (ISISE) in Coimbra, for making SIF 2024 a successful conference. DA - 19.06.2024 KW - Fire resistance KW - Fire test KW - Intumescent coating KW - Steel KW - Tension member PY - 2024 DO - https://doi.org/10.30779/cmm_SIF24 SP - 1173 EP - 1183 PB - CMM – Portuguese Steelwork Association AN - OPUS4-60815 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Burkert, Andreas T1 - Technik, Teamwork und Wirksamkeit - Ein Berufsleben als Ingenieur für die technische Sicherheit N2 - Der Vortrag beleuchtet verschiedene Aspekte einer ingenieurtechnischen Tätigkeit zur Gewährleistung der technischen Sicherheit. Er gibt Einblicke in die unterschiedlichen Herausforderungen und die Komplexität der Aufgabenstellungen. An Beispielen wird dargestellt, wie die Ergebnisse der Tätigkeit für die Gesellschaft wirksam werden. T2 - Tag der Technik CY - Berlin, Germany DA - 16.07.2024 KW - Atmosphärische Korrosion KW - Korrosionsversuche KW - Korrosionsschäden KW - Korrosionsschutz PY - 2024 AN - OPUS4-60636 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Eichner, Lukas T1 - LUKAS’ JACKET: A test structure for model and monitoring based lifetime management of offshore jacket support structures N2 - The goal of the experiments is to demonstrate that systems like three-dimensional jackets possess redundancies that, despite the reduced fatigue life of individual components, enable reliable operation if an appropriate maintenance concept is in place. In practice, individual potentially faulty components in the structure have been handled conservatively so far. To move away from this approach, methods and strategies in the field of life cycle management that enable economically optimal and reliable operation must be transferred from scientific research to practice. Experiments are the preferred method to establish the proof of concept. To realistically simulate the operational lifetime of a jacket structure through an experiment, cyclic loads must be applied to the structure to replicate typical fatigue processes. To ensure that the test structure is not a "disposable product" and can undergo multiple test cycles, the experimental concept includes system-level and component-level tests. The latter are conducted on removable joints. These elements at the nodes of the structure have been manufactured in multiple variations, both to potentially contain mentioned flaws and to undergo more load cycles individually than the main structure. Once the removable joint is sufficiently pre-damaged and thus the reduced remaining fatigue life is established, the element is inserted into the overall structure. The defined maintenance strategy is then implemented on the entire system. This strategy consists of structural health monitoring (SHM), inspections, and repairs. At defined intervals, cyclic loading is interrupted to apply dynamic loads. Using the installed monitoring system and coupled operational modal analysis (OMA), the modal parameters of the structure are determined, which can help identify potential system damage. Optimal sensor placement (OSP) can be determined based on a maximum value of information (VoI) across the entire pre-posterior predicted service life. For detailed investigations at the hotspots, inspections are conducted using non-destructive methods, among others. Overall global and local information about the structure's condition is gathered these methods, which are then incorporated into models describing the structure through Bayesian updating. This allows for initial system identification based on different system responses and later updating of the predicted parameters of analytical and numerical models. Utilizing the updated models, decisions regarding maintenance actions, such as further inspections or repairs, are made, which are subject to uncertainties. The probabilistic models enable a reliability- and risk-based maintenance strategy, where, for example, maximum failure rates can act as triggers for maintenance actions. These decisions are relevant for the planned duration of the simulated operational lifetime, as well as for potential lifetime extensions, which are currently of significant importance in practice. Optimizing the maintenance strategy for the operational lifetime of the structures with these methods will lead to a higher utility of the offshore wind farm. The work associated with the test structure encompasses a variety of topics (including fatigue, damage detection and identification, reliability, Bayesian updating, system identification, SHM, maintenance planning, decisions under uncertainties), which are integrated through corresponding models and methods. All these models have been and are being applied in the numerical accompaniment of the experiments. By applying them to a structure that includes the relevant locations and aspects of real-world structures, both well-functioning and suboptimal parts of the established framework will be revealed. T2 - 20th EAWE PhD Seminar on Wind Energy CY - Visby, Sweden DA - 23.09.2024 KW - Offshore Jacket Support Structure KW - Test Structure KW - Fatigue KW - Lifetime Management KW - Structural Health Monitoring PY - 2024 AN - OPUS4-61146 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Erning, Johann Wilhelm T1 - Risiken in der Trinkwasserinstallation N2 - Die neue Trinkwasserrichtlinie gibt erweiterte Vorgaben zu Risikobewertungen in der gesamtemn kette von der Aquelle zum Zapfhahn. Der Vortrag beschreibt das präventive Konzept der Risikovermeidung über bewertete Werkstoffe und das Regelwerk. T2 - 19. Erfahrungsaustausch Trinkwasserverordnung CY - Brandenburg, Germany DA - 10.10.2022 KW - Korrosion KW - Trinkwasser KW - hygienische Bewertung KW - Risikobewertung PY - 2022 AN - OPUS4-55981 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schartel, Bernhard T1 - Sustainability Meets Flame Retardancy – Fun, Food for Thought, or Future N2 - Überblick über den State-of-the-Art und aktuelle Trends mit den Schwerpunkten: - nachwachsende Rohstoffe in flammgeschützten Polymerwerkstoffen (flammgeschützte Biopolymere und Biokomposite; biomass-basierte Flammschutzmittel, nachwachsende Hilfsstoffe aus Abfallströmen) - Nachhaltigkeit und Flammschutz - Konzepte von Analogie bis Out-of-the-Box. T2 - IK 2022, 10. Institutskolloquium Biozide & Flammschutzmittel - Materialien, Anwendungen und Trends CY - Weißandt-Gölzau, Germany DA - 11.10.2022 KW - Nachhaltigkeit KW - Nachwachsende Rohstoffe KW - Flammschutz KW - Biopolymerkomposite PY - 2022 AN - OPUS4-55983 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Fürst, Richard A1 - Häßler, Dustin A1 - Hothan, Sascha T1 - Influence of the profile type and bar orientation on the performance of intumescent coatings applied to steel tension bars N2 - Intumescent coatings are commonly used in civil engineering to improve the fire resistance of steel constructions. Especially in the case of tension bars, where mostly circular or rectangular solid sections are used, intumescent coatings offer an efficient measure to improve the fire resistance taking advantage of profile-following application and low coating thickness requirements. Thus, the architectural appearance of slender profiles can be preserved. The paper describes real-scale mechanically loaded and unloaded fire tests of circular and rectangular solid steel tension bars with intumescent coating. The aim of these tests is to investigate the influence of the different profile types as well as different bar orientations on the performance of intumescent coatings. The results are used to specify a normative test and assessment procedure to be implemented in a new European standard for determining the contribution of intumescent coatings to the fire resistance of circular or rectangular bars used as tension members. KW - Fire test KW - Intumescent coating KW - Steel tension member KW - Fire resistance PY - 2022 DO - https://doi.org/10.1016/j.firesaf.2022.103678 SN - 0379-7112 VL - 134 SP - 1 EP - 14 PB - Elsevier CY - Amsterdam AN - OPUS4-56172 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schartel, Bernhard T1 - Weathering Resistance of Halogen-free Flame Retardancy in E&E Plastics N2 - - Durability of fire retardancy - Impact of different exposure conditions - Degradation with respect to different fire properties/tests T2 - Fire Resistance in Plastics CY - Cologne, Germany DA - 28.11.2022 KW - Durability KW - Flame retardant KW - Thermoplastic Polyurethane KW - Cable KW - EVA KW - Weathering PY - 2022 AN - OPUS4-56444 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Sanchez Olivares, G. A1 - Battig, Alexander A1 - Goller, Sebastian M. A1 - Rockel, Daniel A1 - Ramirez Gonzáles, V. A1 - Schartel, Bernhard T1 - Imparting Fire Retardancy and Smoke Suppression to Leather during Tanning Processes N2 - Leather is considered a luxury good when used in seating and upholstery. To improve safety, flame retardancy in leather is usually achieved through various finishing processes such as spray or roller coating. These treatments require processing steps that cost time and are laborintensive. One avenue to achieving flame retardancy in leather is to add flame retardants during the tanning process. However, the influence on flame retardancy exerted by specific intumescent additives specifically added during leather tanning has yet to be investigated. This work explores the roles played by intumescent additive compounds in flame retarding leather when they are added during tanning instead of applied as a coating. Via a systematic investigation of various compound mixtures, the flame retardant effects in the condensed and the gas phases are elucidated. The results show a strong impact of melamine in the gas phase and of polyphosphates in the condensed phase. Their impact was quantified in fire and smoke analysis, showing a 14% reduction in the peak of heat release rate, strongly reduced burning lengths, and a 20% reduction in total smoke release compared to nontreated leather. These results illuminate the key role played by specific compounds in the flame retardancy of leather, particularly when they are added specifically during the tanning process instead of being applied as a coating. This method has great potential to reduce processing steps, lower costs, and improve material safety. KW - Leather KW - Fire protection KW - Intumescent additives KW - Smoke suppression PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-564777 DO - https://doi.org/10.1021/acsomega.2c05633 SN - 2470-1343 VL - 7 IS - 48 SP - 44156 EP - 44169 PB - ACS AN - OPUS4-56477 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Chan, Yin Y. A1 - Schartel, Bernhard T1 - It takes two to Tango: Industrial Benchmark PU-Foams with expandable Graphite/P-Flame Retardant Combinations N2 - Polyurethane foams (PUF) are generally flammable, so they are limited in some applications due to strict fire safety requirements. In this study, three distinct industrial benchmark polyurethane foams containing synergistic combinations of expandable graphite (EG) and phosphorous flame retardants (P-FR) were investigated one by one for their fire performance and smoke behavior. This paper aims to substantiate the hypothesis that the combination of EG and P-FR used in polyurethane foams yields a top-notch composite in terms of flame retardancy and smoke behavior by meeting the demanding requirement of low maximum average heat emission (MARHE) and smoke emission in a variety of applications, like advanced materials in construction, lightweight materials for railways, and more. KW - Polyurethane foam KW - Expandable graphite KW - Phosphorus flame retardant PY - 2022 SN - 0948-3276 SN - 0022-9520 VL - 75 IS - 6 SP - 39 EP - 46 PB - Hüthig AN - OPUS4-56501 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Babutzka, Martin T1 - Vorstellung des WIPANOVerbundforschungsvorhabens GELELEK: Forschungsziele und Ergebnisse N2 - Der Vortrag stellt das WIPANO-Forschungsvorhaben GELELEK vor und fasst die wichtigsten erzielten Ergebnisse zusammen. T2 - Sitzung des GfKORR Arbeitskreises „Korrosion und Korrosionsschutz von Eisen und Stahl“ CY - Online meeting DA - 08.12.2022 KW - Deckschichtbildung KW - Gelartige Elektrolyte KW - Korrosionsuntersuchungen KW - Normung KW - Ringversuch KW - WIPANO KW - Zink KW - Korrosion PY - 2022 AN - OPUS4-56502 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Haacke, Nasrin T1 - Vorstellung des Forschungsprojektes RUNOFF: "Neubewertung der Dauerhaftigkeit von Dach- und Fassadenmaterialien und des Eintrags von Schwermetallionen in die Umwelt hervorgerufen durch Runoff„ N2 - Der Vortrag stellt das Forschungsprojekt RUNOFF vor und geht auf das geplante Arbeitsprogramm ein. Darüber hinaus wird die Problemstellung erläutert. T2 - Klempnerfachtagung des Zentralverbands Sanitär-Heizung-Klima CY - Karlstadt a. M., Germany DA - 11.10.2022 KW - Korrosion KW - Kupfer KW - Runoff KW - Zink KW - Atmosphärische Korrosion PY - 2022 AN - OPUS4-56045 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Babutzka, Martin T1 - Stainless steels: Fundamentals and causes for corrosion defects N2 - The presentation gives an overview about the fundamentals on stainless steels. The mechanism of passive layer formation is explained and strategies for securing corrosion protection are given. The influence of a grinding process on corrosion resistance is discussed. T2 - Tech-Day Mettler Toledo CY - Online meeting DA - 23.11.2022 KW - Corrosion KW - Stainless steel KW - Grinding KW - KorroPad KW - Surface PY - 2022 AN - OPUS4-56370 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Mund, M. A1 - Häßler, Dustin A1 - Schaumann, P. A1 - Hothan, Sascha A1 - Schartel, Bernhard T1 - Experimentelle Untersuchungen zur Dauerhaftigkeit von reaktiven Brandschutzsystemen N2 - Reaktive Brandschutzsysteme finden im baulichen Brandschutz Anwendung zur Erhöhung des Feuerwiderstands von Stahlkonstruktionen. Neben den Anforderungen an die Feuerwiderstandsdauer können damit auch Ansprüche an die Ästhetik erfüllt werden. Die profilfolgende Applikation und die geringen Trockenschichtdicken der Produkte ermöglichen es, das filigrane Erscheinungsbild von Stahlkonstruktionen aufrechtzuerhalten. Neben der thermischen Schutzwirkung muss auch die Dauerhaftigkeit der Brandschutzbeschichtung sichergestellt werden. Die Bewertungsmethoden, die auf europäischer Ebene durch das EAD 350402-00-1106 zur Verfügung stehen, zielen auf eine Nutzungsdauer von zehn Jahren ab. Prüfverfahren für einen darüber hinausgehenden Zeitraum sind nicht beschrieben. In diesem Beitrag werden experimentelle Untersuchungen zum Einfluss der Bewitterung auf das Expansionsverhalten, zur thermischen Schutzwirkung und zu den während des Aufschäumens im Brandfall stattfindenden Reaktionen vorgestellt. Die Versuche wurden an einem wasserbasierten und einem epoxidharzbasierten reaktiven Brandschutzsystem durchgeführt. Die Ergebnisse wurden im Rahmen des IGF-Forschungsvorhabens 20470 N erzielt. KW - Brandschutz KW - Reaktive Brandschutzsysteme KW - Brandversuche KW - Alterung KW - Dauerhaftigkeit PY - 2022 DO - https://doi.org/10.1002/stab.202200063 SN - 0038-9145 VL - 92 IS - 2 SP - 93 EP - 102 PB - Ernst & Sohn CY - Berlin AN - OPUS4-56346 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schartel, Bernhard T1 - Composites in Fire and Flame N2 - Overview over the research results of the BAM in the field fire retardancy of composites. In different applications the flame retardancy of composites targets on different fire protection goals in the fire scenarios ignition, developing fire, and fully developed fire. Efficient solutions are tailored to pass a distinct fire test and to fit to a specific material. Flame inhibition as main flame retardancy mode of action combined with a minor mode of action in the condensed phase is general very efficient approach for composites. Alternatively residue design is demanded to achieve good results with only condensed phase mechanisms. Improving the fire stability asks for protective fire residues. T2 - Climate Change @ Fire Science Workshop CY - Berlin, Germany DA - 10.11.2022 KW - Composites in fire KW - Flame retarded composites KW - Fire stability KW - Phosphorous flame retardants KW - Residue design PY - 2022 AN - OPUS4-56299 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Manninger, Tanja T1 - Eco friendly stabilization of loam with calcined clay and potassium hydroxide – calorimetric background study N2 - The low calcination temperature for clays (600° C) and a low CO2 footprint compared to cement make them an interesting material. To find a stabilization method for loam using calcined clays, activation by alkalis was necessary. Therefore (and to keep the mixture environmentally friendly) KOH was used as alkali activator. It could be proven that the alkali activated polymer enhances water resistance of the loam mixture. T2 - First International RILEM Conference on Earthen Construction Fundamentals and Applications for a Circular Economy CY - Paris, France DA - 18.03.2022 KW - Loam KW - Alkali activation PY - 2022 SP - 44 EP - 47 CY - Paris AN - OPUS4-56393 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wiehle, Philipp A1 - Brinkmann, M. T1 - Material behaviour of unstabilised earth block masonry and its components under compression at varying relative humidity N2 - block and mortar types is analysed with particular regard to the influence of varying relative humidity. The uniaxial compressive strength and deformation characteristics of unstabilised earth blocks and mortars as well as of unstabilised earth block masonry are studied in detail and compared to conventional masonry to evaluate whether the structural design can be made accordingly. An increase of 30 % points in relative humidity leads to a reduction of the masonry´s compressive strength between 33 % and 35 % whereas the Young´s modulus is reduced by 24–29 %. However, the ratio between the Young´s modulus and the characteristic compressive strength of earth block masonry ranges between E33/fk = 283–583 but is largely independent of the relative humidity. The results show that the mechanical properties of the investigated unstabilised earth block masonry are sufficient for load-bearing structures, yielding a masonry compressive strength between 2.3 MPa and 3.7 MPa throughout the range of moisture contents investigated. In general, the design concept of conventional masonry can be adapted for unstabilised earth masonry provided that the rather low Young´s modulus as well as the moisture dependence of both, compressive strength and Young´s modulus, are sufficiently taken into account. KW - Compressive strength KW - Earth block masonry KW - Compression tests KW - Stress-strain relation KW - Relative humidity KW - Moisture content PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-562417 DO - https://doi.org/10.1016/j.cscm.2022.e01663 SN - 2214-5095 VL - 17 SP - 1 EP - 15 PB - Elsevier B.V. CY - Netherlands AN - OPUS4-56241 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Battig, Alexander T1 - Flame Retardancy Forge on Sustainability - Fun, Food for Thought, Future N2 - This presentation outlines the role biogenic flame retardant fillers play in attaining sustainability goals associated with the bioeconomy. The talk presents biogenic waste compounds as flame retardant syngergists with phosphorus flame retardants in various polymers. T2 - Climate Change @ Fire Science Workshop CY - Berlin, Germany DA - 10.11.2022 KW - Sustainable KW - Flame retardancy KW - Bioeconomy PY - 2022 AN - OPUS4-56285 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Lehmann, Jens T1 - KorroPad Prüfung in der industriellen Praxis N2 - Anwendungsbeispiele aus dem industrielle Umfeld und Ausblick für weitere Entwicklungen des KorroPads. T2 - GfKORR Jahrestagung - Aktuelles aus der Korrosionsforschung - Nutzen und praktische Anwendungen CY - Frankfurt a.M., Germany DA - 08.11.2022 KW - Korrosion KW - Nichtrostender Stahl KW - KorroPad KW - Korrosionsprüfung PY - 2022 AN - OPUS4-56205 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Müller, Thoralf T1 - Lean Duplex als alternative Güte zu Standardausteniten im Bauwesen N2 - Dieser Vortrag stellt die technologischen und industriellen Meilensteine bei der Etablierung von Lean Duplex Stählen im Bereich des Bauwesens vor. Ein weiterer Blick geht auf die weiteren Entwicklungen an der BAM hinsichtlich der Ausweitung der Kapazitäten und Standorte atmosphärischer Bewitterungsstände der BAM. T2 - GfKORR Jahrestagung 2022 CY - Frankfurt am Main, Germany DA - 08.11.2022 KW - Korrosion KW - Bauwesen KW - Duplexstähle KW - Offshore KW - Tunnel PY - 2022 AN - OPUS4-56198 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Weise, Frank T1 - Innenhydrophobierung von Fahrbahndeckenbetonen als AKR-Vermeidungsstrategie N2 - An den vor allem vor 2006 errichteten Betonfahrbahndecken sind in den letzten Jahren vermehrt AKR-Schäden aufgetreten. Vor diesem Hintergrund wurde durch das BMVBS das ARS 04/2013 erlassen. Dieses wiederum sieht verbindlich im Vorfeld des Neubaus und der Erneuerung von Fahrbahndecken aus Beton im deutschen Bundesautobahnnetz einen Eignungsnachweis für die Gesteinskörnungen vor. Das hatte in den Folgejahren eine drastische Reduzierung der einsatzbaren Gesteinskörnungen zur Folge. Vor diesem Hintergrund wird in dem Beitrag die Leistungsfähigkeit der Innenhydrophobierung als neuartige AKR-Vermeidungsstrategie zur Nutzbarmachung grenzwertig alkaliempfindlicher Gesteinskörnungen aufgezeigt. Dabei wird ein Einblick in die Ergebnisse zweier aufeinander aufbauender BASt-Forschungsvorhaben gegeben. Den Schwerpunkt bildet hierbei die Bewertung des Einflusses der Dosierung des Hydrophobierungsmittels auf die Frisch- und Festbetoneigenschaften im Rahmen von Basisuntersuchungen im Labor. Aufbauend darauf wird das Prüfprogramm eines großmaßstäblichen Technikumsversuchs und der aktuelle Stand der Umsetzung aufgezeigt. T2 - 4. Forschungskolloquium Betonstraßenbau CY - Dresden, Germany DA - 19.01.2023 KW - Alkali-Kieselsäure-Reaktion KW - Betonfahrbahndecke KW - AKR-Vermeidung KW - Innenhydrophobierung PY - 2023 AN - OPUS4-56869 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - RPRT A1 - Hothan, Sascha A1 - Häßler, Dustin A1 - Fürst, Richard A1 - Peter, A. A1 - Wöhr, M. A1 - Rohleder, R. T1 - Entwicklung einer europäischen Prüfnorm zur Bestimmung des Feuerwiderstands von Stahlzuggliedern mit reaktiver Brandschutzbeschichtung anhand belasteter Brandprüfungen T1 - Development of a European test standard for the determination of the fire resistance of steel tension members with intumescent fire protection coating based on loaded fire tests N2 - Ziel des Forschungsvorhabens ist es, ein standardisiertes Prüf- und Bewertungsverfahren zur Bestimmung des Beitrags reaktiver Brandschutzsysteme (RBS) zum Feuerwiderstand von Stahlzuggliedern zu erarbeiten und dieses in ein Entwurfsdokument für eine europäische Prüfnorm zu überführen. Hierzu wurden einerseits bereits vorhandene Erfahrungen und Erkenntnisse genutzt und andererseits mittels Brandversuchen neue Prüfdaten zur Beantwortung bisher offengebliebener Aspekte zum Einfluss der Bauteilorientierung und Profilart erzeugt und ausgewertet. Dadurch wird die prüftechnische Grundlage für eine sichere, zulassungsbasierte Anwendung von reaktiven Brandschutzsystemen auf zugbeanspruchten Stahlbauteilen gelegt und ein einheitliches Sicherheitsniveau etabliert. Der im Rahmen des Forschungsprojektes entwickelte Normentwurf wurde mit den Fachexperten der zuständigen nationalen und europäischen Normungsgremien diskutiert und abgestimmt. Das erarbeitete Prüf- und Auswertungsverfahren basiert auf der Durchführung von Brandversuchen an mechanisch belasteten Stahlzuggliedern mit RBS. Ergänzend sind unbelastete Brandversuche zur Beurteilung des Einflusses der Bauteilorientierung sowie der Eignung bei Schwelbrandbeanspruchung möglich. Die im Projekt durchgeführten experimentellen Untersuchungen liefern die Grundlage für den im Normenentwurf vorgeschlagenen Prüfaufbau der mechanisch belasteten und unbelasteten Brandversuche. Ferner konnte durch die Untersuchungen gezeigt werden, dass sich unter bestimmten Voraussetzungen die Prüfergebnisse von Stahlzuggliedern mit Kreisvollprofil ohne zusätzliche Brandversuche auf entsprechende Zugglieder mit Rechteckvollprofil übertragen lassen. Darüber hinaus konnte belegt werden, dass die Leistungsfähigkeit eines RBS aufgrund unterschiedlicher Bauteilorientierungen abnehmen kann und daher zwingend beim Anwendungsbereich des RBS zu berücksichtigen ist. Hierzu wird ein Temperaturdifferenz-kriterium vorgeschlagen, bei dessen Einhaltung die Wirksamkeit des RBS bei von der horizontalen Referenzorientierung abweichenden Bauteilneigungen noch gleichwertig gegeben ist. Andernfalls bietet der Normenentwurf die Möglichkeit die reduzierte thermische Schutzwirkung des RBS im Assessment zu berücksichtigen. Die Ergebnisse aus dem Forschungsvorhaben wurden bereits auf einem wissenschaftlichen Symposium vorgestellt sowie in einer referierten Fachzeitschrift publiziert. Ferner wurden die Informationen zum Forschungsprojekt und dem Normenentwurf im Rahmen eines Anwenderworkshops interessierten Kreisen zugänglich gemacht. Der im Projekt ausgearbeitete Normenentwurf wird dem zuständigen europäischen Normungsgremien, CEN/TC 127/WG 1, zur Verfügung gestellt und dort zur Abstimmung gestellt. KW - Normung KW - Reaktives Brandschutzsystem KW - Stahl KW - Zugglied KW - Feuerwiderstand KW - Brandversuche PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-569363 SP - 1 EP - 57 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-56936 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Jauregui Rozo, Maria A1 - Sunder, S: A1 - Ruckdäschel, H. A1 - Schartel, Bernhard T1 - Char, gas, and action: Transfer of the flame-retardant modes of action in epoxy resins and their fiber-reinforced composites N2 - Flame retardants are often developed for epoxy resins and then transferred into their fiber-reinforced composites with uncertain results. Understanding this transfer in detail represents a critical scientific challenge. This study systematically compares epoxy resins with their glass-fiber reinforced composites, focusing on bisphenol A diglycidyl ether with the hardener dicyandiamide, the flame retardants melamine polyphosphate, ammonium polyphosphate, and silane ammonium polyphosphate, along with inorganic silicate. The research investigates changes in pyrolysis (thermogravimetry), flammability (UL 94, limiting oxygen index), and fire behavior (cone calorimeter) while also examining the flame-retardant modes of action and overall fire performance. The findings reveal that alterations in the amount of fuel, thermal properties, melt flow, and protective layer significantly impact ignition, flammability, and fire load, with a critical reduction in carbonaceous char within the composites preventing intumescence. This study quantifies the effects and provides a fundamental scientific understanding of the complex transfer process of flame retardants from resins to composites, offering essential insights that are of major importance for developing more effective flame-retardant materials. KW - Glas fibers KW - Epoxy resins KW - Fire behavior KW - Flammability KW - Composites KW - Flame retardants PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-615371 DO - https://doi.org/10.1016/j.polymertesting.2024.108610 SN - 0142-9418 SN - 1873-2348 VL - 140 PB - Elsevier Ltd. AN - OPUS4-61537 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - de Oliveira Guilherme Buzanich, Ana T1 - Exploring new materials for Green Intelligent Building how can our BAMline help N2 - With increasing demand and environmental concerns, researchers are exploring new materials that can perform as well or better than traditional materials while reducing environmental impact. Synchrotron X-ray based methods enable unique tools to probe materials properties via e.g. X-ray spectroscopy and diffraction methods. The BAM plays a central role in this highly collaborative research. The BAMline, a real-life sample materials research beamline, at the Berlin Synchrotron BESSY-II, provides unique insights into materials’ electronic and chemical structure at different time and length scales1. This enables real-time optimization of material properties and performance for various applications, such as energy storage and conversion, catalysis, and deterioration resistance. T2 - DAfStb-Kolloquium CY - Berlin, Germany DA - 16.10.2024 KW - XAS KW - Time-resolved studies KW - Binding materials KW - Cements PY - 2024 AN - OPUS4-61616 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Řepka, Jakub A1 - Vlach, Tomáš A1 - Hájek, Jakub A1 - Fürst, Richard A1 - Hájek, Petr T1 - Flexural behavior of hollow HPC beams with cross-wound CFRP shear reinforcement N2 - This article presents cross-wound carbon fiber-reinforced polymer (CFRP) shear reinforcement of hollow high-performance concrete (HPC) beams. A removable mold used to form the core of the hollow elements was utilized for reinforcement positioning. Basalt fiber-reinforced polymer (BFRP) tensile reinforcement was attached to the removable mold by spacers, and the CFRP shear reinforcement was cross-wound around the BFRP bars from carbon rovings oriented at ± 45° from the longitudinal axis. The flexural, and shear performance of the hollow HPC structural beams was evaluated. To set a comparison, specimens without any shear reinforcement and specimens made of HPC with 80 kg/m3 of dispersed short steel fibers were tested alongside them. The shear capacity of the specimens with CFRP reinforcement evaluated in a three-point bending test was up to 73 % higher compared to those with dispersed steel fibers. The cross-wound CFRP reinforcement also complemented the BFRP tensile reinforcement, as for specimens that failed in tension, the ones with CFRP reinforcement achieved 25 % higher ultimate flexural strength compared to those with dispersed steel fibers. The inclined CFRP mesh affected the orientation of the critical shear crack resulting in higher shear capacity at a longer shear span. Direct effect of the longitudinal reinforcement ratio on the shear capacity was observed. KW - Hollow beam KW - Cross-wound reinforcement KW - Shear capacity KW - Carbon FRP (CFRP) KW - Basalt FRP (BFRP) KW - High-performance concrete (HPC) PY - 2025 DO - https://doi.org/10.1016/j.engstruct.2024.119055 VL - 322 SP - 1 EP - 10 PB - Elsevier B.V. AN - OPUS4-61262 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schneider, Ronald T1 - Impulsvortrag: Ermüdungslebensdauerbewertung mittels Informationen aus Monitoring und Inspektionen N2 - Kontext: Ermüdungsbeanspruchte Tragstrukturen von Windenergieanlagen, Bestimmung der Ermüdungsbeanspruchungen und -zuverlässigkeit auf der Grundlage von Simulationen aus dem Design unter Berücksichtigung von Modellunsicherheiten, Aktualisierung der Ermüdungsbeanspruchungen und -zuverlässigkeit auf der Grundlage von globalen Monitoring- und lokalen Inspektionsinformationen aus dem Betrieb unter Berücksichtigung von Modell- und Messunsicherheiten T2 - 3. Verbundtreffen ReNEW CY - Berlin, Germany DA - 05.09.2024 KW - Modellunsicherheiten KW - Windenergie KW - Ermüdungslebensdauer KW - Tragstrukturen KW - Monitoring KW - Inspektionen PY - 2024 AN - OPUS4-61427 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Erning, Johann Wilhelm T1 - Hygienische Bewertung von SLM-gedrucktem rostfreiem Stahl N2 - Werkstoffe im Kontakt mit Trinkwasser müssen hygienisch bewertet werden. Hier wird ein bereits bewerteter Werkstoff wegen neuer Fertigungsmethoden (additive Fertigung) erneut geprüft und die Besonderheiten durch das Verfahren dargestellt. Der Werkstoff ist auch mit additiver Produktionsmethode geeignet. T2 - GfKORR - Jahrestagung CY - Frankfurt am Main, Germany DA - 05.11.2024 KW - Additive Fertigung KW - Trinkwasser KW - Korrosion KW - Nichtrostender Stahl PY - 2024 AN - OPUS4-61845 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Denkler, Tilman T1 - The Metabuilding Labs approach to Quality Assurance – Standard Operating Procedures and Work Instructions for the O3BETs N2 - The development of the Standard Operating Procedures and Work Instructions for the O3BETs by setting up 3 working roups during Summer 2024 aredescribed. Major achievements are shown and future work is outlined. T2 - 6th General Meeting Metabuilding Labs CY - Szentender, Hungary DA - 26.11.2024 KW - Open innovation test bed KW - Metabuilding Labs KW - Quality management PY - 2024 AN - OPUS4-61866 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Goller, Sebastian M. A1 - Schartel, Bernhard A1 - Krüger, Simone T1 - Phosphorus features halogen –calcium hypophosphite replaces antimony trioxide, reduces smoke, and improves flame retardancy N2 - Replacing antimony trioxide (ATO) in flame retardant formulations is an urgent task due to its toxicity. There are indications that calcium hypophosphite (CaP) may be a promising replacement. This study investigates the decomposition, fire behavior, and smoke release of brominated flame-retarded acrylonitrile butadiene styrene (ABS) under various fire scenarios like ignition, developing fire and smoldering, while replacing ATO with CaP and CaP/talc. Adding 4 wt.-% of talc to CaP formulations showed beneficial effects on flammability due to changes in the viscosity and barrier properties. Synergism between 8 wt.-% talc and CaP improved the protective layer in the developing fire scenario, resulting in a ∼60 % decrease in the peak of heat release rate and reduction of ∼21 % in total smoke production (ref. ABS+Br+ATO). With a conventional index of toxicity (CIT) of below 0.75, ABS+Br+CaP passes the highest requirements according to EN 45545-2. Overall, the CaP/talc materials improve flame retardancy, show less smoke emission under forced flaming conditions, and prevent chronic intoxication and environmental pollution through smoke particles contaminated with antimony. KW - Smoke KW - Flame retardancy KW - Acrylonitrile butadiene styrene KW - Calcium hypophosphite KW - Antimony trioxide PY - 2024 DO - https://doi.org/10.1016/j.tca.2024.179764 SN - 0040-6031 VL - 737 SP - 1 EP - 9 PB - Elsevier Ltd. AN - OPUS4-60063 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Tabaka, Weronika A1 - Meinel, Dietmar A1 - Schartel, Bernhard T1 - Sacrifice Few to Save Many: Fire Protective Interlayers in Carbon- Fiber-Reinforced Laminates N2 - The fire protection of carbon-fiber-reinforced polymer (CFRP) laminates often relies on flame-retardant coatings, but in some applications, their efficacy may diminish upon direct fire exposure due to rapid pyrolysis. This study introduces an innovative approach by integrating protective interlayers within the laminate structure to enhance the fire resistance. Various materials, including ceramic composite WHIPOX, titanium foil, poly(etherimide) (PEI) foil, basalt fibers, rubber mat, and hemp fibers, were selected as protective interlayers. These interlayers were strategically placed within the laminate layout to form a sacrificial barrier, safeguarding the integrity of the composite. Bench-scale fire resistance tests were conducted, where fire (180 kW/m2) was applied directly to the one side of the specimen by a burner while a compressive load was applied at the same time. Results indicate significant prolongation of time to failure for CFRP laminates with protective interlayers, which is up to 10 times longer. This innovative approach represents a potential advance in fire protection strategies for CFRP laminates, offering improved resilience against fire-induced structural failure. KW - Composites in fire KW - Fire resistance KW - Fire retardant interlayers KW - Laminate design KW - Carbon fibre reinforced PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-601943 DO - https://doi.org/10.1021/acsomega.4c01408 SN - 2470-1343 VL - 9 IS - 22 SP - 23703 EP - 23712 PB - ACS AN - OPUS4-60194 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Denkler, Tilman T1 - WP8 - METABUILDING LABS OITB catalogue of testing infrastructures and services, its structuring and exploitation, training and quality management N2 - Developments of Workpackage 8 in the last year are presented. Focuss on the development of quality assurance procedures for the O3BETs. Upcoming activites for the tasks 8.2, 8.3, 8.4, 8.5 and 8.6 are described. T2 - 5th General Meeting Metabuilding Labs Project CY - Online meeting DA - 06.06.2024 KW - Open Innovation Test Bed KW - Quality assurance KW - Quality management PY - 2024 AN - OPUS4-60208 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schartel, Bernhard T1 - Fire Behaviour and Flame Retardancy of Polymeric Materials N2 - Lecture-like introduction in the topic. Fundamental aspects are discussed: Burning of polymers, fire risks, pyrolysis, combustion in the flame, physical chemistry of ignition, flame spread and steady state burning, flame retardancy mechanisms and groups of flame retardants, fire hazards (smoke, toxic products) and environmental concerns, fire testing. T2 - International Combustion Institute Summer School on Near-Wall Reactive Flows CY - Darmstadt, Germany DA - 10.06.2024 KW - Flame retardants KW - Fire behaviour PY - 2024 AN - OPUS4-60246 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Jauregui Rozo, Maria A1 - Sunder, Sruthi A1 - Schartel, Bernhard A1 - Ruckdäschel, Holger T1 - Weaving through fire and force: Fire behavior, fire stability and modes of action between epoxy resin and glass-fiber composites N2 - Several investigation groups have studied the flame-retardancy modes of action and properties of epoxy resins in the past; nevertheless, the selection of suitable flame retardants for epoxy resins remains challenging, and the transfer to fiber composites is difficult. The addition of flame retardants and glass fibers (GFs) to a polymeric system in a fire scenario changes the polymer's pyrolytic path and burning characteristics, reduces the heat released in the combustion, and suppresses the modes of action in the condensed and gas phase. In this study, the thermal analysis, flammability, fire behavior, residue analysis, fire stability, and quantification of modes of action of three different systems with three halogen-free flame retardants (melamine polyphosphate (MPP), ammonium polyphosphate (APP), and silane ammonium polyphosphate (SiAPP)) and three different types of GFs (unidirectional (UD), bidirectional (BD), and woven roving (WR)) will be compared with pure epoxy resin as a reference. T2 - Fire & Polymers CY - New Orleans, LA, USA DA - 12.05.2024 KW - Glass-fiber-composites KW - Epoxy Resins KW - Flame Retardancy KW - Fire Stability KW - Bench-scale Fire Resistance Test PY - 2024 AN - OPUS4-60150 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schepers, Winfried A1 - Kulke, D. T1 - Cone penetration tests and dynamic soil properties N2 - ISO 14837-32:2015 and DIN EN 1998-1/NA:2021 as well as prEN 1997-2:2022 allow for us-ing correlations between the results of in-situ soil penetration tests and shear wave velocity (or shear modulus) to determine soil properties to be used in dynamic analyses. While the ISO and prEN standards even provide some recommendations on specific correlations to be used, the DIN standard does not. Due to the statistical nature of such correlations their general applica-bility has to be verified. We collected data sets from test sites from Germany as well as New Zealand at which cone penetration tests (CPT) as well as seismic site investigation methods were conducted. These sites comprise sandy soils as well as clayey soils, mixed soils as well as glacial soils. We compare the results of several correlations between CPT results and shear wave velocity. The accuracy of such correlations is assessed with respect to the accuracy of seismic in-situ tests. It turns out that for clean sands such correlations between CPT and Vs have a similar order of variability as seismic in-situ tests conducted at the same site. The higher the fines portion of the soil, the higher the variability of the statistical correlations, and conse-quently the less the general applicability. For glacial soils and other special soil types usage of statistical correlations to determine dynamic soil properties is not recommended. T2 - XII International Conference on Structural Dynamics CY - Delft, Netherlands DA - 02.07.2023 KW - Wave propagation KW - Soil properties KW - Dynamic excitation PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-604887 DO - https://doi.org/10.1088/1742-6596/2647/25/252005 VL - 2647 SP - 1 EP - 11 PB - IOP Publishing CY - Bristol AN - OPUS4-60488 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schepers, Winfried A1 - Brinkgreve, RBJ A1 - Appel, S. T1 - Recommendations on finite element modelling of non-seismic excitation in soil-structure interaction problems N2 - Nowadays geotechnical engineering firms have powerful software tools to extent their consult-ing business also into dynamic soil-structure interaction, which before has been restricted to a rather small community of specialized experts in this field, and they certainly do. This is par-ticularly true with respect to non-seismic sources, that is all kinds of human induced vibrations. Hence, there is a demand from clients as well as from contractors to have guidance on the re-quirements as well as the limits of numerical modelling of soil-structure interaction. From the literature as well as from relevant standards, recommendations for the numerical modelling of soil-structure interaction problems involving seismic actions are well known, e. g. ASCE/SEI 4-16. There are, however, some particularities when dealing with human-induced vibrations, which are absent in seismic analyses. For human-induced excitations very little specific guid-ance has been published in the past. A machine foundation on a homogeneous half space ex-cited by harmonic loads with excitation frequency between 4 Hz and 64 Hz has been ana-lysed by means of several commercially available software packages. Parametric studies have been performed to verify if recommendations for seismic soil-structure analyses are valid for non-seismic analyses as well. This paper provides details on the benchmark example and the most important conclusions from the undertaken parametric studies. T2 - XII International Conference on Structural Dynamics CY - Delft, Netherlands DA - 02.07.2023 KW - Numerische Analysen KW - Referenzbeispiel KW - Maschinenfundament KW - Wellenausbreitung PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-604931 DO - https://doi.org/10.1088/1742-6596/2647/8/082014 SN - 1742-6596 VL - 2647 IS - 25 SP - 1 EP - 13 PB - IOP Publishing AN - OPUS4-60493 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schneider, Ronald T1 - Modeling in support of offshore wind farm end-of-life decision making N2 - The EU member states have set out ambitious long-term goals for deploying offshore wind energy. The installed offshore wind capacity is set to increase from 14.6 GW in 2021 to around 320 GW in 2050. This signifies the role of offshore wind energy as a major contributor to reaching the EU’s climate and energy goals. To ensure that the defined targets are met, a significant number of new wind farms has to be installed and existing wind farms reaching the end of their planned life need to be reused efficiently. Some of the relevant reuse alternatives are lifetime extension, repowering based on the existing support structures and repowering with new turbines. As a basis of the decision-making regarding the reuse of existing offshore wind farm, the expected utility of each relevant option should be determined based on the associated expected rewards, costs and risks. The optimal concept maximizes the utility of the decision-maker and fulfills the existing constraints and requirements. To facilitate such a quantitative decision-making, models and methods have to be developed. In particular, models are required that enable predictions of (a) the condition and performance of the turbines and support structures and (b) the renumeration, costs and consequences of adverse events. These predictions have to consider (a) the governing uncertainties, (b) the available information from the planning, construction, installation and operating phase, (b) potential repair, retrofitting and strengthening schemes and (c) possible monitoring, inspection and maintenance regimes for the future operating phase. Over the past years, several models, methods and tools have been developed at the Bundesanstalt für Materialforschung und -prüfung (BAM) to support the structural integrity management of offshore wind turbine substructures. These include: (a) a prototype for reliability-based, system-wide, adaptive planning of inspections of welded steel structures in offshore wind farms, (b) a method for monitoring and risk-informed optimization of inspection and maintenance strategies for jacket structures subject to fatigue, and (c) a probabilistic cost model of inspection and maintenance of welded steel structures in offshore wind farms. This contribution provides an overview on these works and discusses how they can be adapted and extended to support the decision-making regarding lifetime extensions and repowering of offshore wind farms. T2 - 12th International Forum on Engineering Decision Making (12th IFED) CY - Stoos, Switzerland DA - 05.12.2023 KW - Windenergie KW - Offshore Wind KW - Lifetime Extension KW - Repowering PY - 2023 AN - OPUS4-60430 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Häßler, Dustin A1 - Mund, Maximilian A1 - Daus, Lars-Hendrik A1 - Hothan, Sascha A1 - Schaumann, Peter A1 - Schartel, Bernhard T1 - Durability of intumescent coatings and recommendations for test concepts for a working life of more than 10 years N2 - It is an essential requirement for all building products to ensure durability of their fire safety. Throughout the working life of products, intumescent coatings are aged by certain climatic factors. To predict a lifetime of several years, generally the behaviour of the intumescent coating is extrapolated based on accelerated artificial ageing. The established German and European procedures to assess the durability assume a working life of at least 10 years. For a longer period, additional evidence is required; yet the procedure and the specifications to justify this are not described. In addition to addressing this formal lack, from a scientific point of view it is necessary to investigate the degradation of intumescent coatings in detail and to propose a reliable test concept to assess durability for more than 10 years. This paper summarises the existing knowledge about the ageing of intumescent coatings. The results of various demanding weathering approaches are presented for two intumescent coatings tested in a joint research project. Moreover, formulations with a reduced amount of functionally relevant components were analysed to gain insight into the associated effects. Derived from these research results and knowledge, recommendations are proposed to assess the durability of intumescent coatings for more than 10 years based on a combination of verifications. KW - Ageing KW - Fire protection KW - Intumescent coating KW - Steel construction KW - Working life PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-603852 DO - https://doi.org/10.1016/j.firesaf.2024.104173 SN - 0379-7112 VL - 146 SP - 1 EP - 10 PB - Elsevier B.V. AN - OPUS4-60385 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Häßler, Dustin T1 - Fire resistance testing of steel tension members with hollow section protected by intumescent coating N2 - Steel tension members with hollow sections are used in applications such as trusses. To ensure the fire resistance, the steel must be prevented from heating up too quickly. A suitable solution is the application of intumescent coatings. However, the approval-based scope of application of these products generally does not include steel tension members with hollow section. This is mainly due to the lack of a corresponding European test and assessment standard. To investigate the characteristics to be considered when testing these structural members and assessing the contribution of the intumescent coating to the fire resistance, several mechanically loaded fire tests were carried out using a special tension test furnace. The fire tests have shown that intumescent coatings can provide a significant improvement in the fire resistance of steel tension members with hollow section. However, this specific application generally places particularly high demands on the performance of the intumescent coating. This is partly due to the four-sided fire exposure and the mainly filigree cross sections, which both result in high section factors. In addition, there is an increased crack formation due to the tensile load. As a result, the thermal protection of the tested intumescent coating on the tension members decreased compared to columns with the same section factor and fire exposure. Consequently, the presence of a mechanical load in the fire test as well as the type of loading affect the thermal protective performance of the intumescent coating and shall be considered. T2 - Structures in Fire Conference 2024 CY - Coimbra, Portugal DA - 19.06.2024 KW - Fire resistance KW - Fire test KW - Intumescent coating KW - Steel KW - Tension member PY - 2024 AN - OPUS4-60389 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Burkert, Andreas T1 - Korrosion und Korrosionsschutz metallener Werkstoffe- elektrochemische Grundlagen N2 - Ausgehend von den Grundlagen der Korrosion stellt der Vortrag die Möglichkeiten des Korrosionsschutzes mit Zink vor. Dabei wird sowohl auf den kathodische Korrosionsschutz mit aktiven Zink-Anoden, als auch auf den Korrosionsschutz durch Deckschichtbildung an Zink und Zinküberzügen eingegangen. Veränderte Umweltbedingungen in Europa in den letzten Jahrzehnten, ermöglichen mit Schichtdicken um 80 µm einen Korrosionsschutz von über 100 Jahren, wenn konstruktive Randbedingungen beachtet werden. T2 - Seminar VSVI-NRW: KKS-Kostensenkung und Kilmaschutz im konstruktiven Ingenieurbau CY - Bochum, Germany DA - 25.06.2024 KW - Korrosion KW - Korrosionsschutz KW - Zinküberzüge KW - Dauerhaftigkeit PY - 2024 AN - OPUS4-60483 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kemmler, Samuel T1 - Simulating Piping Erosion in Suction Buckets N2 - This presentation gives an overview of the recent achievements in simulating piping erosion during the installation process of suction bucket foundations for offshore wind turbines. The physical correctness of the code is validated, and the simulation code's performance on the LUMI supercomputer is presented. The simulation results are compared to experimental data. T2 - Forschungsbesuch CY - Aix-en-Provence, France DA - 14.05.2024 KW - Offshore wind turbine KW - Suction bucket KW - Coupled fluid-particle simulation KW - High-performance computing PY - 2024 AN - OPUS4-60136 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Dudziak, Mateusz A1 - Bhatia, Riya A1 - Dey, Rohit A1 - Ullrich, Matthias S. A1 - Schartel, Bernhard T1 - Phosphor-enriched wastewater products as sustainable flame retardant in PLA N2 - Revolutionizing our polymer industry for adaption to a sustainable carbon circular economy has become one of today’s most demanding challenges. Exploiting renewable resources to replace fossil-fuel—based plastics with biopolymers such as poly(lactic acid) (PLA) is inevitable while using waste streams as a raw material resource at least is promising. When it comes to using PLA as technical polymer, its high flammability must be addressed by flame retardants compatible with the thermoplastic processing of PLA and its compostability. This study proposes microalgae enriched with phosphorus from wastewater (P-Algae) as an elegant way towards a kind of sustainable organophosphorus flame retardant. The concept is demonstrated by investigating the processing, pyrolysis, flammability, and fire behavior of PLA/P-Algae, while varying the P-Algae content and comparing P-Algae with four alternative bio-fillers (phosphorylated lignin, biochar, thermally treated sewage sludge, and metal phytate) with different P-contents as meaningful benchmarks. T2 - EcoFRam2024 CY - Valencia, Spain DA - 22.05.2024 KW - PLA KW - Flame retardancy KW - Phosphorylated algae KW - Wastewater flame retardants KW - Zink phytate KW - Phosphorylated lignin KW - Thermally treated sludge PY - 2024 AN - OPUS4-60142 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schartel, Bernhard T1 - More than the sum of its parts – synergistic FR-combinations N2 - Efficient flame retardancy is often achieved only when applying synergistic multicomponent systems. Flame retardants are combined or used together with adjuvants or synergists to enhance their efficiency, reduce the amount required, or reduce the costs; fibers and fillers contribute to fire properties crucially. Although the main flame-retardant modes of action are known, the detailed scientific understanding usually falls short, when it comes to complex synergistic multicomponent systems, the important tiny optimizations, or quantifying in terms of specific fire properties. This paper tries to illuminate the concept of synergistic flame retardants. The need for the multicomponent approach and the main phenomena are described. Thought-provoking impulses are delivered on how the understanding of multicomponent systems promotes the evidence-based development of future flame retardant polymeric materials. Multicomponent systems are discussed in their capacity as general powerful strategy for achieving and optimizing flame retardant polymeric materials. This paper is based mainly on the overall conclusions and concrete results of several projects performed in the group of the author. Thanks to my (former) students and co-operation partners in these projects. Thanks for financing to DFG (Scha 730/8-1 Scha 730/8-2, Br 3376/1-1, Scha 730/19-1), AiF IGF (438 ZN, 17833N/2, 19078 N/2), and BMBF (03X0111C, 01DN16040). T2 - Fire & Polymers CY - New Orleans, LA, US DA - 12.05.2024 KW - Flame retardants KW - Synergy KW - Composites KW - Adjuvants PY - 2024 AN - OPUS4-60082 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Klein, Ulrich T1 - Korrosion an Rohren aus ferritischem Stahl 1.4521 N2 - An Trinkwasserrohren aus ferritischem Stahl (1.4521) sind bei einigen größeren Bauvorhaben massive Korrosionsschäden aufgetreten. Die Leckagen treten ausschließlich durch Spaltkorrosion in Pressverbindungen auf, wo konstruktionsbedingt ein mit Wasser gefüllter Spalt zwischen der Rohr-Außenseite und dem Pressfitting gebildet wird. Im Vortrag werden die gewonnenen Erkenntnisse aus verschiedenen Schadensfällen der jüngeren Vergangenheit vorgestellt. T2 - GfKORR e.V. Arbeitskreis Schadensanalyse CY - Berlin, Germany DA - 09.03.2024 KW - Spaltkorrosion KW - Chromstahl KW - Trinkwasser PY - 2024 AN - OPUS4-60098 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Dudziak, Mateusz A1 - Schartel, Bernhard T1 - Phosphor-enriched wastewater products as sustainable flame retardant in PLA N2 - Revolutionizing our polymer industry for adaption to a sustainable carbon circular economy has become one of today’s most demanding challenges. Exploiting renewable resources to replace fossil-fuel—based plastics with biopolymers such as poly(lactic acid) (PLA) is inevitable while using waste streams as a raw material resource at least is promising. When it comes to using PLA as technical polymer, its high flammability must be addressed by flame retardants compatible with the thermoplastic processing of PLA and its compostability. This study proposes microalgae enriched with phosphorus from wastewater (P-Algae) as an elegant way towards a kind of sustainable organophosphorus flame retardant. The concept is demonstrated by investigating the processing, pyrolysis, flammability, and fire behavior of PLA/P-Algae, while varying the P-Algae content and comparing P-Algae with four alternative bio-fillers (phosphorylated lignin, biochar, thermally treated sewage sludge, and metal phytate) with different P-contents as meaningful benchmarks. T2 - Polymers for Sustainable Future CY - Prague, Czech Republic DA - 24.06.2024 KW - PLA KW - Flame Retardancy KW - Thermally Treated Sludge KW - Phosphorylated Algae KW - Zink Phytate KW - Wastewater Flame Retardants KW - Phosphorylated Lignin PY - 2024 AN - OPUS4-60619 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hupp, Vitus A1 - Schartel, Bernhard A1 - Flothmeier, K. A1 - Hartwig, A. T1 - Pyrolysis and flammability of phosphorus based flame retardant pressure sensitive adhesives and adhesive tapes N2 - Pressure-sensitive adhesive tapes are used in a variety of applications such as construction, aircrafts, railway vehicles, and ships, where flame retardancy is essential. Especially in these applications, phosphorus-based flame retardants are often chosen over halogenated ones due to their advantages in terms of toxicity. Although there are pressure-sensitive adhesives with phosphorus flame retardants available on the market, their flame-retardant modes of action and mechanisms are not entirely understood. This research article provides fundamental pyrolysis research of three phosphorus-based flame retardants that exhibit different mechanisms in a pressuresensitive adhesive matrix. The flame-retardants modes of action and mechanisms of a 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO) derivate, an aryl phosphate, and a self-synthesized, covalently bonded DOPO derivate (copolymerized) are investigated. The blended DOPO derivate is volatilized at rather low temperatures while the covalently bonded DOPO derivate decomposes together with the polymer matrix at the same temperature. Both DOPO derivates release PO radicals which are known for their flame inhibition. The aryl phosphate decomposes at higher temperatures, releases small amounts of aryl phosphates into the gas phase, and acts predominantly the condensed phase. The aryl phosphate acts as precursor for phosphoric acid and improves the charring of the pressure sensitive adhesive matrix. All flame retardants enhance the flammability of the adhesives depending on their individual mode of action while the covalently bonded flame retardant additionally improves the mechanical properties at elevated temperatures making it a promising future technology for pressure-sensitive adhesives. KW - Pyrolysis of flame retardant KW - Pyrolysis gas chromatography KW - Mass spectrometry KW - Phosphorus flame retardant KW - Decomposition mechanism KW - Flame retardant pressure sensitive adhesives KW - Flame retardancy PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-607192 DO - https://doi.org/10.1016/j.jaap.2024.106658 SN - 0165-2370 SN - 1873-250X VL - 181 SP - 1 EP - 31 PB - Elsevier B.V. AN - OPUS4-60719 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Degener, Sebastian T1 - Load Identification and Damage Detection by a Digital Twin of a Bridge applying Bayesian Model Calibration N2 - A digital twin for decision making during the life cycle of civil infrastructure is a promising concept combining simulation models with corresponding structure-specific sensor data to support maintenance decisions or to investigate the reliability. The sensor data quality as well as the model quality of the digital twin, comprising on modeling assumptions and correct model parameters strongly influences the prognosis results. T2 - 10th European Workshop on Structural Health Monitoring (EWSHM 2024) CY - Potsdam, Germany DA - 10.06.2024 KW - Load identification KW - Damage detection KW - Digital Twin KW - Bayesian Model Calibration KW - Bridge model PY - 2024 AN - OPUS4-62186 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Vollmer, Malte A1 - Degener, Sebastian A1 - Bolender, Artjom A1 - Bauer, Andre A1 - Liehr, Alexander A1 - Stark, Andreas A1 - Schell, Norbert A1 - Barriobero-Vila, Pere A1 - Requena, Guillermo A1 - Niendorf, Thomas T1 - Time resolved insights into abnormal grain growth by in situ synchrotron measurements N2 - Large oligo-crystalline or single-crystalline metallic materials are of great interest for numerous applications, and a recently developed strategy for promoting abnormal grain growth induced by a cyclic heat treatment opens up new opportunities to manufacture single crystals with a size of several centimeters. So far, the entire available knowledge on this kind of abnormal grain growth has been elaborated based on time discrete observations and, thus, detailed insights into the interplay of elementary mechanisms are still lacking in open literature. The present study reveals time resolved insights into this kind of abnormal grain growth for the first time. It was possible to break down the influence of the individual heat treatment phases by in situ synchrotron high energy X-ray diffraction analysis during cyclic heat reatment. The results obtained not only help to gain a deep understanding of the abnormal grain growth mechanisms, they will also be the basis for an adjustment of the cyclic heat treatment process to improve its efficiency and to eventually obtain even larger single crystals. KW - Single crystals KW - Grain growth method KW - Synchrotron diffraction KW - High-energy X-ray diffraction KW - Grain boundary migration PY - 2023 DO - https://doi.org/10.1016/j.actamat.2023.119168 SN - 1359-6454 VL - 257 SP - 1 EP - 9 PB - Elsevier Ltd. AN - OPUS4-62188 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Nandish, Ranjith A1 - Knaust, Christian A1 - Zehfuß, J. T1 - Numerical investigations of a large fire exposure crib test - presenting different pyrolysis modelling methodologies and numerical results N2 - The need for numerical-based approaches to investigate the fire behaviour in buildings with combustible components is growing due to the increasing use of timber by the construction industry in order to meet the "Climate Action Plan 2050". This requires consideration of the complex kinetic processes that take place during the burning of the wood in the numerical models. This is accomplished by using computational fluid dynamics (CFD) to numerically model the material pyrolysis and combustion processes. This paper presents three different approaches for simulating the behaviour of a wood crib fire using the Fire Dynamics Simulator (FDS). These approaches are based on either prescribing the burning rate of the wood directly from the physical experiments or using the kinetic parameters to govern the underlying processes, such as pyrolysis. Wooden crib fire experiments carried out by the RISE research institute in Sweden inside the combustion chamber were used to validate all the methods. The numerical results from the method, which utilized the experimentally determined burning rate, were in good agreement with the experimental results, with a maximum deviation of 6% in the case of HRR. On the other hand, the model that needs kinetic parameters as its input has shown maximum discrepancies of 12% and 33% compared to experimental results. These methods are sensitive to the input parameters and the extent of dependency needs to be investigated. KW - Wooden buildings KW - Ppyrolysis KW - Wood combustion KW - Wood fire loads PY - 2024 SN - 1099-1018 SP - 1 EP - 25 PB - John Wiley & Sons Ltd. AN - OPUS4-62253 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Jafari, Abbas T1 - Bayesian inference of constitutive law parameters for crack localization using full-field displacement measurements N2 - Physics-based models of mechanical structures are widely adopted for assessing and predicting the behaviour of structures. In the context of structural mechanics, the constitutive law that describes the stress-strain relation forms an important modelling component, which suffers from a considerable amount of uncertainties. These uncertainties primarily arise due to the inherent simplifications and assumptions placed in favor of facilitating the modeling process. Bayesian techniques have been proven to be effective for tackling uncertainties associated with the identification of material model parameters and quantifying the confidence level that can be associated with the placed modeling assumptions. We present a Bayesian framework for the identification of constitutive parameters of quasi-brittle materials suffering strain localization effects, via the use of full-field displacement measurements. The proposed framework explores the idea of force-based Finite Element Model Updating (FEMU-F), which relies on measured full-field displacements and aggregated forces. In particular, the scheme takes advantage of FEMU-F, in contrast to the conventional FEMU, where the information from full-field displacements is directly incorporated into the model. We also address the uncertainties involved in the measured displacements, by treating them as additional unknown variables to be identified, alongside the constitutive parameters. These unknown variables collectively form the inputs to a well-defined objective function, which forms the basis for the Bayesian inference problem. To efficiently solve this Bayesian problem, we employ a variational Bayesian scheme that relies on approximate posteriors represented as multivariate normal distributions. We demonstrate the proposed framework for the parameter identification of a nonlinear path-dependent gradient damage constitutive law, which exhibits strain localization and softening behaviour. The first example illustrates the effectiveness of the inference procedure, highlighting the advantage of FEMU-F in incorporating information about cracks. The second example demonstrates a sub-domain analysis suitable for inferring models with limited domain knowledge; e.g. with uncertain Dirichlet boundary conditions. T2 - EMI 2024 IC – ASCE Engineering Mechanics Institute 2024 International Conference CY - Vienna, Austria DA - 11.09.2024 KW - Bayesian inference KW - Gradient damage model KW - Full-field measurements PY - 2024 AN - OPUS4-62248 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schartel, Bernhard A1 - Humphrey, J.K. A1 - Gibson, A.G. A1 - Hörold, Andreas A1 - Trappe, Volker A1 - Gettwert, V. T1 - Assessing the structural integrity of carbon-fibre sandwich panels in fire: Bench-scale approach N2 - The fire resistance of lightweight sandwich panels (SW) with carbon fibre/epoxy skins and a poly(methacryl imide) (PMI) foam core is investigated in compression under direct application of a severe flame (heat flux=200 kW m−2). A bench-scale test procedure was used, with the sample held vertically. The epoxy decomposition temperature was quickly exceeded, with rapid flash-over and progressive core softening and decomposition. There is a change in failure mode depending on whether the load is greater or less than 50% of the unexposed failure load, or in other words if one or two skins carry the load. At high loads, failure involved both skins with a single clear linear separation across each face. There is an inflection in the failure time relationship in the ∼50% load region, corresponding to the time taken for heat to be transmitted to the rear face, along with a change in the rear skin failure mode from separation to the formation of a plastic hinge. The integrity of the carbon front face, even with the resin burnt out, and the low thermal diffusivity of the core, both play key roles in prolonging rear face integrity, something to be borne in mind for future panel design. Intumescent coatings prolong the period before failure occurs. The ratio of times to failure with and without protection is proposed as a measure of their effectiveness. Apart from insulation properties, their adhesion and stability under severe fire impact play a key role. KW - Carbon fibres KW - Sandwich KW - Structural composites KW - Fracture KW - High-temperature properties KW - Surface treatments PY - 2019 DO - https://doi.org/10.1016/j.compositesb.2018.11.077 SN - 1359-8368 VL - 164 SP - 82 EP - 89 PB - Elsevier AN - OPUS4-46908 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Yin, Huajie A1 - Sypaseuth, Fanni D. A1 - Schubert, M. A1 - Schoch, R. A1 - Bastian, M. A1 - Schartel, Bernhard T1 - Routes to halogen‐free flame‐retardant polypropylene wood plastic composites N2 - Developing halogen‐free flame retardants with reasonably high efficiency, which thus function at limited loadings in polypropylene‐based wood/plastic composites (WPC), is still a challenge. Cost‐effective flame‐retarded WPC have been identified as a way to open the door to an interesting, broader spectrum of application in the building and transportation sectors. This work imparts a systematic comprehensive understanding and assessment of different basic routes to halogen‐free flame‐retarded WPC, taking into account economic and environmental considerations. Cheap, halogen‐free single‐component flame retardants and their multicomponent systems are investigated at reasonable filling grades of 20 wt%. The basic routes of promising synergistic multicomponent systems are discussed, and their potential and Limits assessed. Optimizing the consistency of fire residue; closing the surface of inorganic‐organic residual layers; the thermal stabilization and design of the residue, eg, synergistic combination of ammonium polyphosphate and expandable graphite; and the combination of different flame‐retardant mechanisms, eg, intumescence and flame inhibition, are proposed as promising routes to boost the flame‐retardant efficiency. KW - Flammability KW - Halogen‐free KW - Multicomponent systems KW - Polypropylene KW - Wood plastic composite (WPC) PY - 2019 DO - https://doi.org/10.1002/pat.4458 SN - 1099-1581 SN - 1042-7147 VL - 30 IS - 1 SP - 187 EP - 202 PB - Wiley AN - OPUS4-46909 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Moustapha, M.E. A1 - Farag, Z.R. A1 - Krüger, Simone A1 - Geesi, M.H. A1 - Friedrich, J.F. T1 - Potentiometric studies on the influence of poly(vinylpyrrolidone) on the thermal degradation behavior of poly(vinyl chloride) blends N2 - The thermal degradation behavior of poly(vinyl chloride) (PVC) and poly(N-vinylpyrrolidone) (PVP) blends was investigated using potentiometric measurements of the released HCl gas during the degradation process, estimating the degree of discoloration of the degraded samples and measuring the thermal stability values (Ts) values. The influence of the PVP percentage in the blend and, moreover, the addition of commercial dibasic lead carbonate stabilizer to the blend on its thermal stability was studied. It was found that the dehydrochlorination rate of the blend was promoted by increasing the PVP concentration in the blend. KW - Poly(vinyl chloride) KW - Poly(N-vinylpyrrolidone) KW - Potentiometry PY - 2019 DO - https://doi.org/10.3139/120.111304 SN - 0025-5300 VL - 61 IS - 2 SP - 179 EP - 183 PB - Carl Hanser CY - München AN - OPUS4-47360 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Le, Quynh Hoa A1 - Bäßler, Ralph A1 - Bettge, Dirk T1 - On the corrosion mechanism of CO2 transport pipeline steel caused by condensate: Synergistic effects of NO2 and SO2 N2 - To study the effects of condensed acid liquid, hereafter referred to as condensate, on the CO2 transport pipeline steels, gas mixtures containing a varying concentration of H2O, O2, NO2, and SO2, were proposed and resulted in the condensate containing H2SO4 and HNO3 with the pH ranging from 0.5 to 2.5. By exposing the pipeline steel to the synthetic condensate with different concentration of acidic components, the corrosion kinetic is significantly changed. Reaction kinetic was studied using electrochemical methods coupled with water analysis and compared with surface analysis (scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), and X-ray diffractometry (XRD)) of corroded coupons. The results showed that, although the condensation of NO2 in the form of HNO3 causes faster general corrosion rate, it is the condensation of SO2 in the form of H2SO4 or the combination of SO2 and NO2 that may cause much more severe problems in the form of localized and pitting corrosions. The resulting corrosion forms were depended on the chemical nature of acids and their concentration at the same investigated pH. The effects of changing CO2 flow rate and renewing condensate on pitting corrosion were further studied. KW - Carbon capture, utilization and storage technology KW - CCUS KW - Corrosion KW - Condensate KW - Electrochemical characterisation KW - Pitting corrosion KW - Impurities KW - Carbon steel PY - 2019 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-473685 UR - https://www.mdpi.com/1996-1944/12/3/364 DO - https://doi.org/10.3390/ma12030364 SN - 1996-1944 VL - 12 IS - 3 SP - 364, 1 EP - 17 PB - MDPI CY - Basel AN - OPUS4-47368 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kunz, Valentin T1 - Surface chemical transformations of nanoparticles N2 - Nanomaterials are a relatively new class of materials for which a regulatory framework still has to be established and regulators require comprehensive datasets of well characterized nanomaterials for the implementation. Especially information about the surface chemistry of nanoparticles is crucial, since it largely determines their biological and environmental fate. How the surface chemistry changes under relevant ageing conditions is of particular interest, because exposure will normally occur not to the pristine material but to a nanoform that underwent some kind of transformation. In this talk, first a short overview about the contributions of division 6.1 to multiple European-funded projects will be presented, in which surface analytical techniques are used to improve the physical-chemical characterization of nanomaterials. Secondly, a study investigating the surface-chemical transformations of a representative set of titanium dioxide nanoparticles is discussed in more detail. The ageing has partly been performed at the BAM division 7.5, and the surface chemistry was analyzed using time-of-flight secondary ion mass spectrometry (ToF-SIMS) and X-ray photoelectron spectroscopy (XPS). By analyzing the complex mass spectra with principal component analysis (PCA), it was possible to identify even subtle changes that occur upon ageing. T2 - Abteilungsseminar CY - BAM, Berlin, Germany DA - 25.2.2019 KW - Nanoparticles KW - Surface Chemistry KW - Ageing KW - Titanium Dioxide KW - ToF-SIMS PY - 2019 AN - OPUS4-47444 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Rabe, Sebastian A1 - Sánchez-Olivares, G. A1 - Pérez-Chávez, R. A1 - Schartel, Bernhard T1 - Natural keratin and coconut fibres from industrial wastes in flame retarded thermoplastic starch biocomposites N2 - Natural keratin fibres derived from Mexican tannery waste and coconut fibres from coconut processing waste were used as fillers in commercially available, biodegradable thermoplastic starch-polyester blend to obtain sustainable biocomposites. The morphology, rheological and mechanical properties as well as pyrolysis, flammability and forced flaming combustion behaviour of those biocomposites were investigated. In order to open up new application areas for these kinds of biocomposites, ammonium polyphosphate (APP) was added as a flame retardant. Extensive flammability and cone calorimeter studies revealed a good flame retardance effect with natural fibres alone and improved effectiveness with the addition of APP. In fact, it was shown that replacing 20 of 30 wt. % of APP with keratin fibres achieved the same effectiveness. In the case of coconut fibres, a synergistic effect led to an even lower heat release rate and total heat evolved due to reinforced char residue. This was confirmed via scanning electron microscopy of the char structure. All in all, these results constitute a good approach towards sustainable and biodegradable fibre reinforced biocomposites with improved flame retardant properties. KW - Biomaterials KW - Biodegradable KW - Calorimetry KW - Composites KW - Flame retardance PY - 2019 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-472518 DO - https://doi.org/10.3390/ma12030344 SN - 1996-1944 VL - 12 IS - 3 SP - 344, 1 EP - 24 PB - MDPI AN - OPUS4-47251 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Sut, Aleksandra A1 - Metzsch-Zilligen, E. A1 - Großhauser, M. A1 - Pfaendner, R. A1 - Schartel, Bernhard T1 - Synergy between melamine cyanurate, melamine polyphosphate and aluminum diethylphosphinate in flame retarded thermoplastic polyurethane N2 - The multicomponent flame retardant system of melamine polyphosphate (MPP), melamine cyanurate (MC) and aluminum diethylphosphinate (AlPi) is proposed and investigated for thermoplastic polyurethane (TPU). The synergy between those additives and the resulting superior fire performance are discussed. Systematically varied sets of flame retarded TPU with various MPP/MC/AlPi ratios were investigated in terms of fire behavior, pyrolysis products and mechanical properties. The total amount of the additives was always 30 wt.-%. Further, the influence of various AlPi concentrations was investigated. The optimal MPP:MC ratio was determined while keeping the amount of AlPi constant. The combination of 8 wt.-% MPP, 12 wt.-% MC and 10 wt.-% is proposed as the most promising halogen free flame retardant formulation for TPU, because it yielded a reduction in PHRR from 2660 kW/m2 (TPU) to 452 kW/m2 and enabled V-0 classification in the UL 94 test. Combinations of MPP and MC as well a high concentration of AlPi are beneficial for the mechanical properties e.g. tensile strength and elongation at break of the formulations and could be a strong competitor to commercial flame retarded TPUs. KW - Thermoplastic polyurethane KW - Synergy KW - Melamine cyanurate KW - Melamine polyphosphate KW - Aluminum diethylphosphinate KW - Rapid mass calorimeter PY - 2019 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-472523 DO - https://doi.org/10.1016/j.polymertesting.2019.01.001 SN - 0142-9418 VL - 74 SP - 196 EP - 204 PB - Elsevier Ltd. AN - OPUS4-47252 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Burkert, Andreas A1 - Babutzka, Martin T1 - Korrosionsschutz durch Deckschichtbildung und Passivität N2 - Metallene Konstruktionswerkstoffe reagieren infolge ihres thermodynamisch instabilen Zustandes mehr oder weniger stark mit Stoffen aus der Umgebung. Eine große Rolle bei diesen Reaktionen spielt das Feuchtigkeitsangebot an der Metalloberfläche, welches nicht zwingend mit einem sichtbaren Wasserfilm einhergehen muss. An der Atmosphäre bilden sich an sauberen Metalloberflächen bei etwa 80 % relativer Luftfeuchte, bei versalzten Oberflächen auch schon ab etwa 25 % r. F., Feuchtfilme aus. Im Feuchtfilm laufen grundsätzlich die gleichen elektrochemischen Reaktionen ab, wie diese von wässrigen Medien bekannt sind. Dabei geht das Metall zunächst in Ionenform und in nachgelagerten Reaktionen in einen thermodynamisch stabilen Zustand in Form unterschiedlichster Oxid- und Hydroxidverbindungen über. Die so entstehenden Korrosionsprodukte können im Feuchtigkeitsfilm begrenzt löslich oder unlöslich sein und lagern sich auf den Oberflächen der Konstruktionswerkstoffe häufig als feste Korrosionsprodukte ab bzw. wachsen dort auf. Je nachdem wie die Korrosionsprodukte strukturell zum Untergrund passen, können sich dichte, sehr gut haftende Schichten ausbilden oder poröse, dicke Schichten ohne nennenswerte Haftung aufwachsen. Wachsen dichte, porenfreie Schichten mit guter Haftung auf, die im umgebenden Medium unlöslich sind, wird die weitere Auflösung des Metalls stark gehemmt. Man spricht dann von der Ausbildung schützender Deckschichten bzw. von Passivschichten auf welcher der Korrosionsschutz und damit die Dauerhaftigkeit vieler Konstruktionswerkstoffe beruhen. Kaesche bezeichnete die Passivität sehr treffend als „optimalen Grenzfall des Korrosionsschutzes durch Schichten von Korrosionsprodukten“. Aus technischer Sicht hält Kaesche eine Unterscheidung von Deckschichten bzw. Passivschichten für nicht zwingend erforderlich, da beide die Korrosionsgeschwindigkeit in gleichem Maß herabsetzen können. Die Übergänge zwischen den meist dickeren und dadurch sichtbaren Deckschichten und den meist dünnen, nicht sichtbaren Passivschichten sind fließend. T2 - 18. Tagung "Korrosionsschutz in der maritimen Technik" CY - Hamburg, Germany DA - 30.01.2019 KW - Korrosionsschutz KW - Überzüge KW - Deckschichten KW - Passivität PY - 2019 SN - 978-3-935406-70-3 VL - 18 SP - 25 EP - 38 AN - OPUS4-47307 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CHAP A1 - Pistol, Klaus A1 - Huismann, S. A1 - Diederichs, U. A1 - Pimienta, P. A1 - Jumppanen, U.M. A1 - Mindeguia, J.C. T1 - Stress-strain-relation, compressive strength and modulus of elasticity N2 - This chapter report the most recent experimental results on mechanical behaviour at high temperature of high-performance concretes. After a short introduction, subsection 5.2 describes the main testing methods that were used in the analysed studies. Sub-section 5.3 collects and compares; the temperature-dependency of the compressive strength and modulus of elastici1ty of many experimental studies. The influence of parameters such as the initial compressive strength, the type of aggregate, the presence of additions, the W/C ratio, the moishrre content and the way the mechanical test was performed is analysed. Sub-section 5.4 presents the experimental results obtained under a constant temperature, i.e. creep tests at high temperature. Sub-section 5.5 presents experimental results obtained under increasing temperahrre. These results allow assessing the free thennal strain of concrete (when no mechanical load is applied) and the so-called "transient the1mal strain". Finally, subsection 5.6 collects and analyses the few results conceming the temperature-dependency of the tensile strength of high-perfo1mance concretes. KW - Stress-strain-relation KW - High temperature PY - 2019 SN - 978-3-319-95431-8 SN - 978-3-319-95432-5 SN - 2213-204X SN - 2213-2031 SP - 89 EP - 105 PB - Springer CY - Swizerland AN - OPUS4-47212 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Bäßler, Ralph T1 - Book review: Advanced ceramic and metallic coating and thin film materials for energy and environmental applications N2 - This book provides a state‐of‐the‐art overview on the processing, characterization, and modelling of metallic and ceramic materials used for energy and environmental applications. 17 scientists show a collection of current knowledge in 8 chapters. This book fulfills its intention to provide a reference book containing a collection of publications on thin films and coatings made of ceramic and metals used for energy and environmental applications. It covers a broad range of this topic and provides a comprehensive insight. Graduate and undergraduate students of materials science and mechanical engineering can find an overview on this topic to step in this interesting field of engineering. KW - Ceramic KW - Coating KW - Thin film KW - Energy PY - 2019 DO - https://doi.org/10.1002/maco.201970034 SN - 0947-5117 SN - 1521-4176 VL - 70 IS - 03 SP - 567 EP - 568 PB - WILEY-VCH Verlag GmbH & Co. KGaA CY - Weinheim AN - OPUS4-47517 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Zirnstein, Benjamin A1 - Schulze, Dietmar A1 - Schartel, Bernhard T1 - The impact of polyaniline in phosphorus flame retardant ethylene-propylene-diene-rubber (EPDM) N2 - Usually elastomers are loaded with high amounts of flame retardants to fulfill fire safety requirements. In this study the potential char precursor polyaniline (PANI) and the established fire retardant pentaerythritol (PER) were implemented in ethylene-propylene-diene monomer rubber (EPDM). PANI and PER were used in low loadings (7 phr) and combined with two phosphorous flame retardants, Ammonium polyphosphate (APP) and a piperazine-pyrophosphate/phosphoric acid compound (FP), to boost their performance. A comprehensive study is presented, explaining the impact of PANI on curing and mechanical properties, including compensation for the plasticizer-like effect of APP in EPDM, and improved flame retardancy. In the cone calorimeter test, the combination of EPDM/FP/PANI reduced the effective heat of combustion by 20%. All nine EPDM rubber compounds were investigated with the LOI and UL 94 tests, cone calorimeter, FMVSS 302 and glow wire testing to quantify fire performance. The PANI containing EPDM rubbers, EPDM/APP/PANI and EPDM/FP/PANI outperformed the corresponding PER containing, EPDM/APP/PER and EPDM/FP/PER rubbers in various tests. Moreover, the study investigated the impact of PANI and PER on the mode of action of the phosphorus species and showed that the addition of PANI increased the amount of phosphorus in the condensed phase. To receive a broader understanding of the flame retardant mode of action of PANI in combination with APP and FP, calculations were carried out to estimate the impact of PANI on the protective layer effect. KW - EPDM KW - Rubber KW - Flame retardant KW - Polyaniline KW - Pentaerythritol PY - 2019 DO - https://doi.org/10.1016/j.tca.2019.01.019 SN - 0040-6031 VL - 673 SP - 92 EP - 104 PB - Elsevier B.V. AN - OPUS4-47503 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Teng, Jun A1 - Tang, De-Hui A1 - Zhang, Xiao A1 - Hu, Wei-Hua A1 - Said, Samir A1 - Rohrmann, Rolf G. T1 - Automated modal analysis for tracking structural change during construction and operation phases N2 - The automated modal analysis (AMA) technique has attracted significant interest over the last few years, because it can track variations in modal parameters and has the potential to detect structural changes. In this paper, an improved density-based spatial clustering of applications with noise (DBSCAN) is introduced to clean the abnormal poles in a stabilization diagram. Moreover, the optimal system model order is also discussed to obtain more stable poles. A numerical Simulation and a full-scale experiment of an arch bridge are carried out to validate the effectiveness of the proposed algorithm. Subsequently, the continuous dynamic monitoring system of the bridge and the proposed algorithm are implemented to track the structural changes during the construction phase. Finally, the artificial neural network (ANN) is used to remove the temperature effect on modal frequencies so that a health index can be constructed under operational conditions. KW - Automated Modal Analysis for Tracking Structural Change during Construction and Operation Phases PY - 2019 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-475116 UR - https://www.mdpi.com/1424-8220/19/4/927/pdf DO - https://doi.org/10.3390/s19040927 SN - 1424-8220 VL - 19 IS - 4 SP - 927, 1 EP - 23 PB - MDPI AG CY - Basel, Switzerland AN - OPUS4-47511 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Ogle, K. A1 - Erning, Johann Wilhelm A1 - Zhou, P. T1 - Interactions between elemental components during the dealloying of Cu-Zn alloys N2 - The elemental dissolution of Cu-Zn alloys was investigated as a function of Zn content ranging from 0 to 45 wt%. Atomic emission spectroelectrochemistry (AESEC) was utilized to directly monitor Cu2+ and Zn2+ release and oxide growth as function of time during potentiodynamic experiments. It was determined that Cu dissolution undergoes a simultaneous mechanism of Cu2O formation and Cu2+ release. The addition of Zn in Cu-Zn alloy does not measurably change the dissolution mechanism of Cu2+ and the rate of aqueous Cu2+ was only dependent on the potential. Zn dissolution was however blocked by the formation of a Cu(0) film which shifted the Zn dissolution in the anodic direction. KW - Copper KW - Brass KW - Dealloying KW - Drinking water PY - 2019 DO - https://doi.org/10.1016/j.electacta.2018.09.181 SN - 0013-4686 VL - 293 IS - Januar SP - 290 EP - 298 PB - Elsevier AN - OPUS4-46269 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Wachtendorf, Volker A1 - Geburtig, Anja A1 - Trubiroha, P. ED - Ziegahn, K.-F. T1 - Messung der effektiven UV-Bestrahlung bei der Bewitterung von Polymeren N2 - Bei der Bestrahlung und Bewitterung von polymeren Werkstoffen wird die Degradation durch eine Absorption von Strahlung initiiert und meistens durch weitere Klimagrößen, wie z.B. Wärme, Feuchte und atmosphärische Gase beeinflusst. Die Messung einer effektiven Bestrahlungsstärke und ihre zeitliche Integration sind deshalb von großer Bedeutung und zwar sowohl für die Kontrolle der Funktion des Bewitterungs- oder Bestrahlungsgerätes als auch als zusätzliche Angabe der wirkenden Beanspruchung. Photochemische Prozesse werden beim Sehen oder allgemeiner bei Farbstoffen schon durch sichtbare (VIS) Strahlung, dagegen bei der Erythembildung der Haut und der Photodegradation von Polymeren erst durch die energiereicheren Photonen der ultravioletten (UV) Strahlung initiiert. Die spektrale Empfindlichkeit des Auges und die Erythembildung sind im VIS- bzw. UV-Bereich sehr stark wellenlängenabhängig, was durch die Angabe der mit der spektralen Hellempfindlichkeit V(λ) des Auges bewerteten VIS-Strahlung in Lux (lx) bzw. die mit der Erythem-Wirkfunktion Serythem bewertete UV Strahlung als dimensionsloser UV-Index berücksichtigt wird. Spektrale Empfindlichkeiten. Die Photodegradation von Polymeren ist im UV-Bereich ebenfalls stark wellenlängenabhängig, was bisher bei der radiometrischen UV-Messung nicht berücksichtigt wurde. Seit Mitte der 70er Jahre, als die lx- bzw lxh- Messung bei der Strahlungsbeanspruchung langsam durch die Ermittlung der radiometrischen UV-Bestrahlungsstärke bzw. der UV-Bestrahlung im gesamten UV-Bereich abgelöst wurde, gab es hier bei der Bewitterungsprüfung keine weiteren Fortschritte auf dem Gebiet der Charakterisierung der Strahlungsbeanspruchung im UV-Bereich. Seit Jahren liegen zahlreiche Ergebnisse über die spektrale Empfindlichkeit von Photo-degradationsprozessen vor, die zeigen, dass die spektrale Empfindlichkeit im Bereich der Globalstrahlung an der kurzwelligen Grenze bei ca. 300 nm, am größten ist und im langwelligen UV-Bereich bei ca. 400 nm gegen Null geht. Die Messungen der radiometrischen Größen UV-Gesamtbestrahlungsstärke und UV-Gesamtbestrahlung erfasst deshalb über weite Wellenlängenbereiche Strahlungsanteile, die für die Photodegradation bedeutungslos sind und mittelt über potenziell bedeutsame Änderungen im kurzwelligen UV-Bereich hinweg. Es wird das Konzept eines neuen UV-Radiometers vorgestellt, dessen spektrale Empfindlichkeit einer mittleren spektralen Empfindlichkeit der Photodegradation von Polymeren entspricht. Die effektive UV-Bestrahlungsstärke und UV-Bestrahlung kann dadurch wesentlich genauer erfasst werden. T2 - 48. Jahrestagung der GUS 2019 CY - Stutensee, Germany DA - 27.03.2019 KW - UV-Bestrahlungsstärke PY - 2019 SN - 978-3-9818507-3-4 SP - 89 EP - 100 AN - OPUS4-47896 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Bäßler, Ralph T1 - Book review: Materials and processes for CO2 capture, conversion and sequestration N2 - This book provides an overview on research‐topics who need to be investigated when dealing with this topic, basing on the symposium in 2014. It addresses the key challenges involved in CCS materials design, processing and modelling. Readers can get an overview on topics one should consider when working in these field and selecting current Journal articles. KW - CCS KW - CO2-Corrosion KW - Microstructure PY - 2019 DO - https://doi.org/10.1002 maco.201970044 SN - 0947-5117 SN - 1521-4176 VL - 70 IS - 04 SP - 751 EP - 752 PB - WILEY-VCH Verlag GmbH & Co. KGaA CY - Weinheim AN - OPUS4-47909 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Günther, Martin T1 - Investigating the fire phenomena of rigid polyurethane foams N2 - This work investigates the fire phenomena of rigid polyurethane foams (RPUF) in detail. Rigid polyurethane foams (RPUF) are widely used in industry and daily life because of their outstanding mechanical and thermal insulating properties. In case of fire, cellular polymers like RPUF behave differently from bulk materials, the reason for this is their low thermal inertia. The aim of this study is to investigate the fire phenomena of RPUF in detail. Characterized by simultaneous physical and chemical processes which interact, depend, and compete with each other, the combustion of RPUF is a highly complex occurrence. Therefore it is necessary to study all aspects in detail. The fire phenomena that were examined are gasification, liquefaction, charring and structural integrity as well as collapse. The comprehensive understanding of the processes taking place during combustion is the foundation of customized development of successful flame retardant approaches. Advanced cone calorimeter investigations provide insight into the fire behavior under forced flaming conditions. Thermocouples in the inside of specimens give information about the temperature gradient and temperature of the pyrolysis zone during combustion. Changes in the morphology and thickness of the pyrolysis zone were examined using a hot-stage microscope, as well as SEM images of cross-sections of quenched foam specimens. Furthermore, fire phenomena were characterized using LOI and thermal analysis. By using a multimethodological approach and systematically varied sets of Polyurethane and Polyisocyanurate foams, new insights into the burning of RPUF were won. The detailed knowledge of fire phenomena is essential for future development of tailored flame retardant strategies for RPUF. T2 - AMI Fire Retardants in Plastics 2019 CY - Pittsburgh, PA, USA DA - 02.04.2019 KW - Fire behavior KW - Rigid polyurethane foam PY - 2019 AN - OPUS4-47835 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Auersch, Lutz T1 - Compliance and damping of piles for wind tower foundation in nonhomogeneous soils by the finite-element boundary-element method N2 - A combined finite-element boundary-element method for the dynamic interaction of the soil with flexible structures such as single piles or complete wind energy towers has been developed. Flexible piles in different soils are analysed in frequency domain. The different parameters such as the stiffness of the soil, the bending stiffness and the radius of the hollow pile are analysed for their influence on the complex compliances. The results have been determined as specific power laws which are different for the different load cases (horizontal, rocking, coupling) and for the different soil models (Winkler, continuum with constant, root-parabolic and proportional-linear stiffness variation). The strongest influence of the soil stiffness can be found for the homogeneous soil and the horizontal component. Winkler soils have a weaker influence than the corresponding continuous soils. An offshore wind energy tower has been modeled and calculated for wind and wave loads. KW - Pile foundation KW - Finite-element boundary-element method KW - Pile bending stiffness KW - Soil stiffness KW - Continuously inhomogeneous soils KW - Layered soils KW - Wind energy tower PY - 2019 DO - https://doi.org/10.1016/j.soildyn.2018.12.005 SN - 0267-7261 VL - 120 IS - 5 SP - 228 EP - 244 PB - Elsevier CY - London AN - OPUS4-47891 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz T1 - Vehicle-track-soil interaction and train-induced ground vibration – Theory and measurements in Germany, Switzerland and France N2 - Three measurement campaigns of train-induced ground vibrations are evaluated for the vehicle-track-soil interaction. Ground vibrations, track vibrations and vehicle vibrations have been measured for train passages and impulse excitation and compared with theoretical results. The soil and the track-soil system are calculated by wavenumber integrals. The influence of the vehicle is introduced by a substructure method. By comparing theory and measurement the different components of excitation force and ground vibration can be analysed, the quasi-static excitation, track-alignment errors, the out-of-roundness of wheels, the wheel and rail roughness, and moreover, scattered axle impulses and ineffective high-frequency parts of the wheelset accelerations and forces. T2 - Recent Advance in Structural Dynamics CY - Lyon, France DA - 15.04.2019 KW - Vehicle-track-soil interaction KW - Train-induced ground vibration KW - Vibration measurements PY - 2019 SP - 810 EP - 821 PB - University of Southampton CY - Southampton AN - OPUS4-47892 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz T1 - Vehicle-track-soil interaction and train-induced ground vibration: Theory and measurements in Germany, Switzerland and France N2 - Three measurement campaigns of train-induced ground vibrations are evaluated for the vehicle-track-soil interaction. Ground vibrations, track vibrations and vehicle vibrations have been measured for train passages and impulse excitation and compared with theoretical results. The soil and the track-soil system are calculated by wavenumber integrals. The influence of the vehicle is introduced by a substructure method. By comparing theory and measurement the different components of excitation force and ground vibration can be analysed, the quasi-static excitation, track-alignment errors, the out-of-roundness of wheels, the wheel and rail roughness, and moreover, scattered axle impulses and ineffective high-frequency parts of the wheelset accelerations and Forces. T2 - Recent Advance in Structural Dynamics CY - Lyon, France DA - 15.04.2019 KW - Vehicle-track-soil interaction KW - Train-induced ground vibration PY - 2019 AN - OPUS4-47893 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz T1 - Roughness and wheelset acceleration from axle-box measurements for understanding the generation and mitigation of ground vibrations N2 - Two measurement campaigns of train-induced ground vibrations are evaluated for the vehicle-track-soil interaction. Ground vibrations, track vibrations and vehicle vibrations have been measured for train passages and impulse excitation and compared with theoretical results. The soil and the track-soil system are calculated by wavenumber integrals. The influence of the vehicle is introduced by a substructure method. By comparing theory and measurement the different components of excitation force and ground vibration can be analysed, the quasi-static excitation, track-alignment errors, the out-of-roundness of wheels, the wheel and rail roughness, and moreover, scattered axle impulses and ineffective high-frequency parts of the wheelset accelerations and forces. T2 - ISO/TC 108/SC 2/WG 8 Working group Ground-borne noise and vibration from rail systems CY - Berlin, Germany DA - 12.03.2019 KW - Vehicle-track-soil interaction KW - Train-induced ground vibration PY - 2019 AN - OPUS4-47894 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Bäßler, Ralph T1 - Rezension: Beurteilung von Gefahrgutlagern mit Hilfe einer Tabellenkalkulation N2 - Dieses Werk bietet Personen, die sich mit Gefahrgutlagerung beschäftigen einen Ansatz und ein Hilfsmittel für deren Arbeit. Dieses Buch ist lediglich ein Nachdruck der Masterarbeit. Einer redaktionellen Überarbeitung, am besten mit Rückmeldungen von Anwendern, sieht der Rezensent mit Interesse entgegen. KW - Gefahrgut KW - Gefahrstoff PY - 2019 DO - https://doi.org/10.1002 maco.201970045 SN - 0947-5117 SN - 1521-4176 VL - 70 IS - 04 SP - 6 EP - 7 PB - WILEY-VCH Verlag GmbH & Co. KGaA CY - Weinheim AN - OPUS4-47910 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bäßler, Ralph A1 - Stoljarova, A. A1 - Regenspurg, S. T1 - Material qualification in Saline, copper containing geothermal water N2 - By exposure and electrochemical tests in the laboratory the Cu-effect on corrosion behavior of carbon steel, high-alloyed steels and Ti-alloy can be assessed. Critical materials specific properties were determined by static exposure and electrochemical tests in an artificial geothermal water with high salinity and low pH, containing Cu. Conclusions were drawn using characteristic potential values. It could be shown that significant Cu-deposition and -precipitation only occurred in combination with carbon steel. High-alloyed materials (S31603, S31653, S31700, S31703, S31803 and N08904) prevent the disturbing Cu-agglomeration. Therefore, they are suitable to be chosen for future design of the piping system, either in massive or in cladded form, if formation of crevices with non-metallic materials can be excluded. From the interactions and pitting corrosion point of view, R50400 seems to be most favorable. T2 - NACE International Corrosion Conference 2019 CY - Nashville, TN, USA DA - 24.03.2019 KW - Copper KW - Corrosion KW - Steel KW - Geothermal energy PY - 2019 SP - 1 EP - 11 PB - NACE International CY - Houston AN - OPUS4-47911 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Aristia, G. A1 - Le, Quynh Hoa A1 - Bäßler, Ralph A1 - Roth, C. T1 - The Effect of Different Polyaniline Types in Silicon Dioxide Containing Coatings for Carbon Steel Protection in Artificial Geothermal Brines N2 - According to the results of the experiments carried out, the following points can be concluded: 1. Exposure tests showed that specimens with the addition of SiO2 particles and polyaniline particles exhibit better corrosion resistance than specimens with the addition of only polyaniline particles or binder only. 2. Open circuit potential measurements showed that in the beginning of the experiments, both coatings had an open circuit potential 100 mV higher than carbon steel. Within one day of immersion, the potential of carbon steel increased significantly, indicating the formation of oxide layer. After extended exposure the carbon steel potential sat between PS1 (which had higher potential) and PS2 (which had a lower potential) and all three were in the range –600 mV to –500 mV vs Ag/AgCl. 3. Both coatings PS-1 and PS-2 were degraded with increasing exposure time, shown by the decrease of absolute impedance value at low frequency range after 2, 4, and 6 days exposure. 4. Potentiodynamic test was performed after 3 hours and 6 days exposure, and it was shown that the coating in the initial stage exhibited more passive behavior than the specimens exposed for 6 days. T2 - NACE International Corrosion Conference 2019 CY - Nashville, TN, USA DA - 24.03.2019 KW - Geothermal KW - Coating KW - Polyaniline KW - Corrosion PY - 2019 SP - 13121-1 EP - 13121-14 PB - NACE International CY - Houston AN - OPUS4-47913 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Le, Quynh Hoa A1 - Bäßler, Ralph A1 - Bettge, Dirk A1 - Kratzig, Andreas A1 - Knauer, S. T1 - Factors Influencing Droplet Corrosion in Dense Phase CO2 N2 - Recent studies have shown that even at a very low concentration of impurities (less than 100 ppmv of SO2, NO2, O2 and H2O) the droplet formation and condensation of sulfuric and nitric acids in dense phase CO2 are possible and observable. To reveal the mechanism of droplet corrosion in dense phase CO2 at high pressure and low temperature, further studies on factors that affect wettability and resulting corrosion behaviors of transport pipeline steels are needed. In this study, effects of surface morphology were investigated by varying surface roughness of carbon steel coupons exposed to CO2 stream containing impurities to measure the wettability by contact angle and to observe the condensation as well as possible droplet corrosion that followed. Other considered factors were: pH of the droplet, temperature, droplet volume, and exposure time. T2 - NACE International Corrosion Conference 2019 CY - Nashville, TN, USA DA - 24.03.2019 KW - CCUS KW - Dense phase KW - CO2 KW - Droplet KW - Corrosion KW - Condensation KW - Carbon steel PY - 2019 SP - 13017-1 EP - 13017-13 PB - NACE International CY - Houston AN - OPUS4-47915 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Zirnstein, Benjamin A1 - Schulze, Dietmar A1 - Schartel, Bernhard T1 - Mechanical and fire properties of multicomponent flame retardant EPDM rubbers using aluminum trihydroxide, ammonium polyphosphate, and polyaniline N2 - In this study, multicomponent flame retardant systems, consisting of Ammonium polyphosphate (APP), aluminum trihydroxide (ATH), and polyaniline (PANI), were used in ethylene propylene diene monomer (EPDM) rubber. The multicomponent system was designed to improve flame retardancy and the mechanical properties of the rubber compounds, while simultaneously reducing the amount of filler. PANI was applied at low loadings (7 phr) and combined with the phosphorous APP (21 phr) and the mineral flame retardant ATH (50 phr). A comprehensive study of six EPDM rubbers was carried out by systematically varying the fillers to explain the impact of multicomponent flame retardant systems on mechanical properties. The six EPDM materials were investigated via the UL 94, limiting oxygen index (LOI), FMVSS 302, glow wire tests, and the cone calorimeter, showing that multicomponent flame retardant systems led to improved fire performance. In cone calorimeter tests the EPDM/APP/ATH/PANI composite reduced the maximum average rate of heat emission (MARHE) to 142 kW·m-2, a value 50% lower than that for the unfilled EPDM rubber. Furthermore, the amount of phosphorus in the residues was quantified and the mode of action of the phosphorous flame retardant APP was explained. The data from the cone calorimeter were used to determine the protective layer effect of the multicomponent flame retardant systems in the EPDM compounds. KW - EPDM KW - Rubber KW - Flame retardant KW - Polyaniline KW - Aluminum trihydroxide (ATH) PY - 2019 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-482769 DO - https://doi.org/10.3390/ma12121932 SN - 1996-1944 VL - 12 IS - 12 SP - 1932, 1 EP - 22 PB - MDPI AN - OPUS4-48276 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Bäßler, Ralph T1 - Book review: Impedance spectroscopy - Theory, experiment and applications N2 - This textbook fulfills its dedication of being the “essential reference for the field, featuring protocols, analysis,fundamentals and the latest advances” of impedance spectroscopy to its readers. It really provides an insight in all facets of this powerful technique. It should not be missed in the bookshelf of electrochemists and all other interested researchers and engineers who want to be on the current state of this technique. KW - Impedance spectroscopy KW - Surface PY - 2019 DO - https://doi.org/10.1002/maco.201970064 SN - 1521-4176 SN - 0947-5117 VL - 70 IS - 6 SP - 1133 PB - WILEY ‐ VCH Verlag GmbH & Co. KGaA CY - Weinheim AN - OPUS4-48210 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Rappsilber, Tim A1 - Krüger, Simone A1 - Below, Philipp T1 - Wood crib fire tests to evaluate the influence of extinguishing media and jet type on extinguishing performance at close range N2 - This paper is intended to be the first study to discuss the fire suppressing performance of the four most common extinguishing media under the same reproducible conditions. The tests were performed in bench-scale and used standardized 5A wood cribs as well as a miniature extinguishing system with a liquid flow rate of 1.4 lmin−1. The tests results present a consistent overview of the fire suppression efficacies of water, water with a foaming agent, nozzle-aspirated foam and compressed air foam. Depending on their jet types, the cooling capabilities of the extinguishing media water and water with a foaming agent were compared to the cooling capability of a full Jet of wet, general and dry foams. The results show that compressed air foam suppressed fire most effectively under the test conditions. Because of the convoluted crib structure, water and water with foaming agents used from a distance are more effective in the form of a full jet rather than a spraying jet. At close range, spraying jets multiply their effectiveness. A slight difference can be observed in the cooling performance of extinguishing foams that use foaming agents from different manufacturers. The paper establishes a link between the foaming agent's cooling capability and its wetting power by relating the results of wood crib fire tests according to DIN EN 3–7 and findings from laboratory immersion tests compliant with DIN EN 1772. KW - CAF KW - Druckluftschaum KW - Löschen KW - Krippe PY - 2019 DO - https://doi.org/10.1016/j.firesaf.2019.04.014 SN - 0379-7112 SN - 1873-7226 VL - 106 SP - 136 EP - 145 PB - Elsevier Ltd. AN - OPUS4-47996 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Pötzsch, Sina T1 - Book review: Practical testing and evaluation of plastics N2 - One can conclude, this first edition of “Practical Testing and Evaluation of Plastics” provides a comprehensive and compact reference. It can be recommended as clear overview as well as introducing manual for everyone working with characterization and testing of plastics. KW - Plastic KW - Testing PY - 2019 DO - https://doi.org/10.1002/maco.201970054 SN - 0947-5117 SN - 1521-4176 VL - 70 IS - 5 SP - 931 EP - 932 PB - Wiley-VCH CY - Weinheim AN - OPUS4-48013 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Burkert, Andreas T1 - Bedingungen für den schadensfreien Einsatz von nichtrostenden Stählen N2 - Unter Passivität versteht man den Korrosionsschutz durch dünne, festhaftende Schichten aus Korrosionsprodukten. Für den schadensfreien Einsatz nichtrostender Stähle ergeben sich daraus zwei grundsätzliche Anforderungen. Erstens muss sich die Passivschicht vollständig ausbilden können. Dabei sind die Oberflächenausführung,die mechanische Bearbeitung,die Elementverteilung, Ausscheidungen, die Wärmeeinbringung z.B. bei der schweißtechnischen Verarbeitung, Anlauffarben, sowie die chemische Nachbehandlung bzw. Konditionierung der Oberflächen von großer Bedeutung. Zweitens muss die Repassivierung von möglichen Defektstellen unter den Einsatzbedingungen möglich sein. Für das Repassivierungsvermögen sind die Legierungszusammensetzung, mögliche kritische Betriebszustände, prozessbedingte Besonderheiten wie etwa Stagnationsbedingungen und Reinigungsprozesse von Bedeutung. T2 - Nichtrostende Stähle - Eigenschaften und Anwendungen CY - Dusseldorf, Germany DA - 14.05.2019 KW - Korrosion KW - Werkstoffauswahl KW - Dauerhaftigkeit PY - 2019 AN - OPUS4-48016 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Babutzka, Martin T1 - Auslagerungsversuche von Standardproben unter verschiedenen atmosphärischen Bedingungen N2 - Der Vortrag berichtet über die Auslagerung von Standardproben nach DIN EN ISO 9223 bis 9226 aus Zink, Stahl, Kupfer und Aluminium auf den verschiedenen atmosphärischen Bewitterungsständen der Bundesanstalt für Materialforschung und -prüfung (BAM). Im Vortrag werden die Masseverluste, Korrosionsgeschwindigkeiten und Korrosivitätskategorien der Standardproben im freibewitterten und überdachten Bereich nach einem Jahr vorgestellt und Unterschiede hinsichtlich der Atmosphärenbedingungen aufgezeigt. Freibewitterte Proben zeigen dabei deutliche Unterschiede hinsichtlich ihres Korrosionsverhaltens im Vergleich zu überdachten Proben. Die ermittelten Korrosivitätskategorien sind sowohl standort- als auch materialspezifisch. T2 - 44. Arbeitskreissitzung „Schadensuntersuchung“ des GfKORR e. V. CY - Frankfurt a. M., Germany DA - 02.04.2019 KW - Korrosion KW - Atmosphärische Korrosion KW - Freibewitterung KW - Auslagerungsversuche PY - 2019 AN - OPUS4-47719 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz T1 - Zur Wirksamkeit und Berechenbarkeit von elastischen Gebäudelagerungen N2 - Es wird die Vorgehensweise erläutert wie die Notwendigkeit einer elastischen Gebäudelagerung geprüft wird. Es werden die Möglichkeiten und Schwächen vereinfachter Rechenverfahren dargestellt. Es folgen weitere Beispiele detaillierter Gebäudemodelle und ihres Schwingungsverhaltens. Schließlich greift eine aktuelle Bachelorarbeit die Fragestellung komplexen Gebäudeschwingungsverhaltens auf. Die letzte Folie zeigt dazu Gebäudemodelle, die an die konkreten Erschütterungsprognosen anknüpfen. T2 - Elastische Gebäudelagerungen CY - Berlin, Germany DA - 23.5.2019 KW - Gebäudemodelle KW - Gebäudeschwingungen KW - elastische Gebäudelagerungen PY - 2019 AN - OPUS4-48089 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Markwart, Jens C. A1 - Battig, Alexander A1 - Zimmermann, Lisa A1 - Wagner, Martin A1 - Fischer, Jochen A1 - Schartel, Bernhard A1 - Wurm, Frederik R. T1 - Systematically controlled decomposition mechanism in phosphorus flame retardants by precise molecular architecture: P−O vs P−N N2 - Flame retardants (FR) are inevitable additives to many plastics. Halogenated organics are effective FRs but are controversially discussed due to the release of toxic gases during a fire or their persistence if landfilled. Phosphorus-containing compounds are effective alternatives to halogenated FRs and have potential lower toxicity and degradability. In addition, nitrogencontaining additives were reported to induce synergistic effects with phosphorus-based FRs. However, no systematic study of the gradual variation on a single phosphorus FR containing both P−O and P−N moieties and their comparison to the respective blends of phosphates and phosphoramides was reported. This study developed general design principles for P−O- and P−N-based FRs and will help to design effective FRs for various polymers. We synthesized a library of phosphorus FRs that only differ in their P-binding pattern from each other and studied their decomposition mechanism in epoxy resins. Systematic control over the decomposition pathways of phosphate (PO(OR)3), phosphoramidate (PO(OR)2(NHR)), phosphorodiamidate (PO(OR)(NHR)2), phosphoramide (PO(NHR)3), and their blends was identified, for example, by reducing cis-elimination and the formation of P−N-rich char with increasing nitrogen content in the P-binding sphere. Our FR epoxy resins can compete with commercial FRs in most cases, but we proved that the blending of esters and amides outperformed the single molecule amidates/diamidates due to distinctively different decomposition mechanisms acting synergistically when blended. KW - Phosphorus KW - Flame retardants KW - Epoxies KW - Mechanistic study KW - Toxicity PY - 2019 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-481549 DO - https://doi.org/10.1021/acsapm.9b00129 SN - 2637-6105 VL - 1 IS - 5 SP - 1118 EP - 1128 PB - ACS AN - OPUS4-48154 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Krüger, Simone A1 - Schartel, Bernhard A1 - Schoch, Rebecca A1 - Schubert, Martina T1 - Holz-Kunststoff-Verbundwerkstoffe - Wie beeinflussen Flammschutzmittel die Rauchgaszusammensetzung im Brandfall? N2 - Der steigende Einsatz von Holz-Kunststoff-Verbundwerkstoffen (Wood Plastic Composite, WPC) erfordert das Wissen um seine spezifischen Eigenschaften, insbesondere dem Brand risiko. Dabei können Flammschutzmittel die Entflammbarkeit, Wärmeabgabe und die Brandausbreitung des Materials verringern. Deshalb sind der gezielte und effiziente Einsatz und die Kenntnis über die Wirkungsweise der Flammschutzmittel im WPC für den Brandschutz von enormer Bedeutung. Dazu gehört auch die Rauchentwicklung im Brandfall. Rauch beeinflusst aufgrund seiner Toxizität und seiner Sichttrübung die Fluchtmöglichkeit der betroffenen Personen. In der Rauchkammer nach ISO 5659-2 wird die Rauchentwicklung von flachen Werkstoffproben ermittelt. Die Rauchgastoxizität bzw. die Rauchgaszusammensetzung wird mithilfe der FTIR (Fourier Transformierte Infrarot)-Spektroskopie ermittelt. Frei werdende Partikel schädigen die Atemorgane und beeinflussen damit auch die Fluchtfähigkeit von Personen im Brandfall. Aussagen zur Partikelemission können mithilfe eines an die Rauchkammer gekoppelten Partikelanalysators getroffen werden. Im Rahmen dieser Arbeit wurden verschiedene flammgeschützte WPC-Systeme hinsichtlich ihres Rauchverhaltens in der Rauchkammer untersucht. Die Ergebnisse zu emittierten toxischen Gasen, Partikeln und zur Rauchentwicklung werden vorgestellt und in Abhängigkeit von den eingesetzten Flammschutzmitteln im WPC diskutiert. KW - Rauchgase KW - Holz-Kunststoff-Verbundwerkstoffe KW - Partikel KW - Flammschutz PY - 2019 DO - https://doi.org/10.1002/bate.201900020 VL - 96 SP - 1 EP - 12 PB - Wiley AN - OPUS4-48157 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schartel, Bernhard T1 - Digging in the dirt: Using natural fibers from industrial waste in flame retarded thermoplastic starch biocomposites N2 - To exploit application fields beyond packaging for biodegradable materials, flame retardancy and increased mechanical strength are usually required. This work focuses on the flammability of a thermoplastic starch/polyester blend reinforced with natural fibers derived from Mexican industry processes wastes, such as keratin fibers from the tannery industry, coconut fibers (coconut industry), and agave tequilana fibers and henequen fibers from tequila industry. Different fiber contents as well as combinations of varying contents of aluminum trihydroxide, expandable graphite, aluminum diethylphosphinate or ammonium polyphosphate are investigated. It is the goal to propose sustainable waste fibers as adjuvants improving the flame retardancy. This work provides the proof of principle for sustainable biodegradable flame retarded biocomposites. T2 - Flame 2018, 30th Annual Conference on Recent Advances in Flame Retardancy of Polymeric Materials CY - San Antonio, TX, USA DA - 19.05.2019 KW - biocomposite KW - sustainable KW - natural fibers KW - renewable KW - industrial waste KW - sustainability KW - thermoplastic starch KW - flame retardant PY - 2019 AN - OPUS4-48143 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Lima, G. T. S. A1 - Silvestro, L. A1 - Durlo Tambara, Luis Urbano A1 - Cheriaf, M. A1 - Rocha, J. C. T1 - Autonomous Self-Healing Agents in Cementitious Materials: Parameters and Impacts on Mortar Properties N2 - The concept of self-healing materials and the development of encapsulated curing agents represent a cutting-edge approach to enhancing the longevity and reducing the maintenance costs of cementitious structures. This systematic literature review aims to shed light on the parameters involved in the autonomous self-healing of cementitious materials, utilizing various encapsulated healing agents such as pellets, granules, and capsules. This review also identifies and selects studies that offer additional insights into the efficacy of the self-healing process in cementitious materials and the influence of these specific encapsulated healing agents on the physical mechanical properties of mortars. This comprehensive approach provides a deep understanding of the interplay between self-healing and the physical–mechanical properties of mortars containing these encapsulated healing agents. The main findings indicate that the cement-to-sand ratio, characteristics of fine aggregates, and encapsulation methods significantly impact crack control, self-healing efficiency, and properties of mortar in both fresh and hardened states. The content of encapsulated healing agents within the cementitious matrix affects both the initial workability or flow and subsequent mechanical properties. While pellets coated with PVA film typically reduce workability in the fresh state and compressive strength, capsules coated with Portland cement and sodium silicate mitigate these effects and improve crack sealing in fresh and hardened states without compromising the self-healing capacity of cracks. The three-point flexural test has emerged as the preferred method for a pre-crack assessment over 28 days, with variations depending on the type of healing agent used. As noted in the literature, water has been identified as the optimal environment for autonomous healing. These findings underscore the potential of encapsulation techniques to enhance self-healing capabilities through the controlled release of agents within the cementitious matrix, thereby advancing the research on and development of intelligent construction materials and increasing the durability of cement-based structures. KW - Self-healing cementitious composite KW - Encapsulated curing agents KW - Pellets KW - Granules KW - Capsules KW - Physical–mechanical properties KW - Autonomous self-healing PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-611860 DO - https://doi.org/10.3390/buildings14072000 SN - 2075-5309 VL - 14 IS - 7 SP - 1 EP - 23 PB - MDPI CY - Basel AN - OPUS4-61186 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Eiz Eddin, Ahmad T1 - Building acoustic analysis of doubly curved beam like shell floors made of CFRP prestressed concrete and its integration into an interdisciplinary optimisation tool N2 - An optimisation tool was developed to reduce the embodied carbon of floor systems. The consideredsystem consists of a doubly curved beam-like shell made of carbon-fibre-reinforced polymer (CFRP) prestressed concrete and an infill layer. The thin-walled design of the system makes it susceptible to sound excitation. Therefore, the optimisation tool considers the static ultimate and serviceability limit states and the sound insulation aspect. Due to a lack of experience with the building acoustic properties of this floor system, it is, in practice, often simplified as a homogeneous floor. This paper aims to investigate its acoustic behaviour in more detail using numerical simulations and to integrate the gained knowledge into the optimisation tool. For this purpose, a simulation concept is set up and implemented. Simulations are carried out for different combinations of geometry and material parameters of the floor system. The data obtained is summarised into linear regression equations that estimate the weighted airborne sound reduction index and the weighted equivalent normalised impact sound pressure level of the system. The optimisation results based on these equations show a clear difference compared to those based on the above-mentioned simplified approach. T2 - IASS 2024 CY - Zurich, Switzerland DA - 26.08.2024 KW - Building acoustic simulation KW - Impact sound pressure level KW - Airborne sound reduction index KW - Doubly curved beam-like shells KW - Optimisation tool KW - Embodied carbon KW - Parametric design KW - Interdisciplinary optimisation PY - 2024 AN - OPUS4-61131 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schartel, Bernhard T1 - Flame and Fire Retarded Composites: Principles and Concepts N2 - Carbon fibre (CF), short glass fibre, and long glass fibre (GF) reinforced polymers are used for diverse applications such as electronics/electrical engineering, transportation (railway vehicles, shipping, aviation) and construction. The fire behaviour of composites differs in comparison to polymers. Fibres behave often inert with respect to pyrolysis, but they change the melt flow and dripping behaviour, the heat absorption and transfer, the amount and properties of the fire residue and so on. Flame and fire retardancy concepts are needed not only suitable for the different fire protection goals typical for each application, but also tailored for composites. The field is illuminated by examples taken from different projects carried out in the group of the author in the last 22 years. The examples target on different applications through achieving V0 in UL 94 testing (reaction to small flame controlling the fire risks in the beginning of a fire), reducing heat release rate and fire load in the cone calorimeter (fire risks under forced flaming combusting controlling the contribution to developing fires) and investigating the fire stability when a severe flame is directly applied (key property in fully developed fires). Approaches to halogen-free flame retardancy in GF reinforced thermoplastics and CF reinforced thermosets are presented as well as building up a bench and intermediate scale testing of composites in fire applying mechanical load and direct flame exposure simultaneously. The understanding of fire behaviour and flame retardancy mode of actions in composites is a promising basis for target-oriented development. The role of flame inhibition, charring and protective layer formation is discussed in composites. Successful concepts are presented for flame retardancy tailored for different application as well as general guidelines for future development. Different phosphorus flame retardants are proposed to achieve halogen-free flame retardancy in applications demanding limited fire risks with respect to ignition and developing fires. Different protective approaches are sketched for addressing the fire resistance of composite that is the most important fire risk for structural applications. T2 - 2nd Conference Flame Retardancy for Composite Applications CY - Berlin, Germany DA - 20.11.2024 KW - Composites KW - Flame retardancy KW - Modes of action KW - Lightweight materials KW - Fire resistance KW - Flammability KW - Flame retardant mechanisms PY - 2024 AN - OPUS4-61726 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Zinas, Orestis A1 - Wilhelm, Sigrid T1 - CPT-based probabilistic design of monopile foundations N2 - This work was presented in the two-day workshop ‘Reliability-based methods in geotechnics’ organized by BAM and DGGT AK 2.15 in cooperation with the DGGT Academy. The presentation provides an overview of the sources of uncertainty in geotechnical analyses. A probabilistic 3D ground model of the cone-tip resistance from CPTs is developed utilizing sparse CPT data from a real offshore wind farm site in the North Sea. The predictive cone tip resistance model is used to derive a design property, such as the friction angle, using geotechnical transformation models. The friction angle profiles are then used to show an example of monopile design under uncertainty. T2 - Workshop: Einführung in die zuverlässigkeitsbasierte Bemessung in der Geotechnik 2024 CY - Berlin, Germany DA - 19.11.2024 KW - Geotechnical site-characterization KW - CPT KW - Spatial variability KW - Gaussian process regression KW - Design of monopiles KW - Offshore wind farms PY - 2024 AN - OPUS4-61716 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Vlach, Tomáš A1 - Řepka, Jakub A1 - Hájek, Jakub A1 - Pošta, Jan A1 - Fürst, Richard A1 - Hájek, Petr T1 - Shear Capacity of Hollow High-Performance Concrete Beams with Cross-Wound Carbon Fiber-Reinforced Polymer Reinforcement N2 - This paper introduces cross-wound CFRP shear reinforcement of hollow HPC beams. The CFRP reinforcement was manufactured in the form of a square tubular mesh from carbon rovings oriented at ±45° from the longitudinal axis. The shear reinforcement was made in two variants from carbon yarns with linear densities of 1600 and 3700 tex. Tensile reinforcement made of BFRP bars was positioned directly around the hollow core and was used as a platform for manual winding of the shear reinforcement. The hollow beams were subjected to a three-point bending test with four configurations of the tensile BFRP reinforcement for better evaluation of the effect of the shear reinforcement under different conditions. The 1600 tex shear reinforcement increased the ultimate flexural strength by at least 89% compared to specimens without any shear reinforcement. The 3700 tex shear reinforcement yielded slightly better results in most cases but was not utilized to its full shear capacity as these specimens always failed in shear due to the delamination of the concrete matrix from the shear reinforcement. There was too much reinforcement in the beam cross-section. KW - Hollow concrete beam KW - Shear reinforcement KW - Composite reinforcement KW - Woven reinforcement KW - Cross-wound reinforcement KW - Fiber-reinforced polymer KW - High-performance concrete PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-623868 DO - https://doi.org/10.3390/polym17010075 SN - 2073-4360 VL - 17 IS - 1 SP - 1 EP - 13 PB - MDPI AN - OPUS4-62386 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Balscheit, Hagen T1 - Buckling Design of Soil Embedded Piles N2 - Monopiles sind die gängigste Gründungskonstruktion für Offshore-Windkraftanlagen, doch größere Turbinen erfordern Pfahldurchmesser über 10 m und Pfahllängen über 60 m, was das Risiko von lokalem Beulen in den eingebetteten Bereichen erhöht. Aktuelle Richtlinien berücksichtigen die Pfahl-Boden-Interaktion nicht ausreichend so dass nur ein vollständig numerischer GMNIA-Nachweis geführt werden kann. Für derartige Berechnungsmodelle fehlen allerdings derzeit noch validierungswerte für eingebettete Schalen. Experimente im Rahmen des VERBATIM-Projekts schließen diese Lücke. T2 - Phd Conference Univiersity Innsbruck CY - Innsbruck, Austria DA - 05.02.2025 KW - Buckling KW - Wind Energy KW - Monopile Foundation PY - 2025 AN - OPUS4-62534 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Lehmann, Jens T1 - Forschungsbericht VH 7604 - Teil 2: Ergebnisse zum Korrosionsverhalten nichtrostender Stähle in den beprobten Straßentunneln N2 - In Straßentunneln sind nichtrostende Stähle weitverbreitete Werkstoffe, die für Konstruktionsteile verschiedenster Art verwendet werden. Straßentunnel sind aus Sicht des Korrosionsschutzes sehr speziell und zählen in Mitteleuropa zu den korrosivsten atmosphärischen Umgebungsbedingungen. Die hier vorgestellten Ergebnisse eines gemeinsamen Forschungsvorhabens von Straßen.NRW, der Bundesanstalt für Materialforschung und -prüfung (BAM), LSBG-Hamburg sowie weiteren Partnern, zeigen geeignete Duplexstähle für Straßentunnelanwendungen. Hierfür wurde eine breit angelegte Parameterstudie durchgeführt und seit 2017 die Korrosionsbedingungen in mehreren Tunneln umfassend untersucht. Die Korrosivität der Tunnelatmosphären wurden anhand normativer Regelwerke bewertet und dem Korrosionszustand von Prüfkörpern aus nichtrostenden Stählen gegenübergestellt. T2 - Infotag "Dauerhaftigkeit der Betriebs- und Sicherheitsausstattung im Straßentunnel" CY - Düsseldorf, Germany DA - 13.02.2025 KW - Korrosion KW - Tunnel KW - Atmosphärische Korrosion KW - Nichtrostender Stahl KW - Edelstahl rostfrei KW - ZTV-ING PY - 2025 AN - OPUS4-62551 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Burkert, Andreas T1 - Vorhaben: Innovation und Sicherheit durch Einsatz von Duplexstählen in Straßentunneln - Ergebnisse der Korrosivitätsbewertung N2 - In Straßentunneln sind nichtrostende Stähle weitverbreitete Werkstoffe, die für Konstruktionsteile verschiedenster Art verwendet werden. Straßentunnel sind aus Sicht des Korrosionsschutzes sehr speziell und zählen in Mitteleuropa zu den korrosivsten atmosphärischen Umgebungsbedingungen. Grund hierfür ist die Kombination aus hoher Feuchtigkeit, Abgasen der Fahrzeuge (SO2, NOx) und dem winterlichen Streusalzeinsatz (Cl-). Die daraus entstehenden feuchten Oberflächenfilme sind hochchloridhaltig und weisen durch Reaktionen mit Schwefeldioxid sehr niedrige pH-Werte auf. Durch die fehlende Abwaschung der Oberflächenfilme können sich Verunreinigungen über die Einsatzzeit aufkonzentrieren. Aufgrund der Gefahr von Spannungsrisskorrosion bei einigen nichtrostenden Stahlsorten in Tunnelatmosphären, sind in der ZTV-ING (Teil 7, Abschnitt 4) sowie in der DIN EN 1993-1-4 (Eurocode 3) Regeln für die Werkstoffauswahl in Tunneln aufgestellt worden, die seit vielen Jahrzehnten gültig sind. Die Korrosivität der Tunnelatmosphären wurden anhand normativer Regel¬werke bewertet und dem Korrosionszustand von Prüfkörpern aus nichtrostenden Stählen gegenübergestellt. T2 - Infotag "Dauerhaftigkeit der Betriebs- und Sicherheitsausstattung im Straßentunnel" CY - Düsseldorf, Germany DA - 13.02.2025 KW - Korrosion KW - Tunnel KW - Atmosphärische Korrosion PY - 2025 AN - OPUS4-62552 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Müller, Thoralf T1 - Qualitätssicherung im Metallbau Vorgehen und erste Erfahrungen N2 - In diesem Vortrag wird ein erster Erfahrungsbericht über den erstmaligen Einsatz eines fertigungsbegleitenden Qualitätssicherungskonzepts an dem Pilotprojekt im Tunnel Menkhauser Berg vorgestellt. Ziel des Qualitätskonzepts war die Sicherstellung der korrosionsschutzgerechten Auswahl, Ausführung und Verarbeitung von nichtrostenden Stählen an Tunnellüfterbauteilen und -baugruppen. Es werden verschiedene Prüfmethoden zur Überprüfung der korrosionsschutzgerechten Verarbeitung von nichtrostenden Stählen vorgestellt und Angaben zum Vorgehen und Fehlerquellen gemacht. T2 - Infotag "Dauerhaftigkeit der Betriebs- und Sicherheitsausstattung im Straßentunnel" CY - Düsseldorf, Germany DA - 13.02.2025 KW - Korrosion KW - Tunnel KW - QM KW - Nichtrostender Stahl KW - Edelstahl rostfrei PY - 2025 AN - OPUS4-62553 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Cunningham, Patrick A1 - Wang, L. A1 - Kane, S. A1 - Kim, A. A1 - Jenkins, B. M. A1 - Miller, S. A. T1 - Lifecycle implications and mechanical properties of carbonated biomass ashes as carbon-storing supplementary cementitious materials N2 - Methods to sequester and store atmospheric CO2 are critical to combat climate change. Alkaline-rich bioashes are potential carbon fixing materials. This work investigates potential co-benefits from mineralizing carbon in biomass ashes and partially replacing high embodied greenhouse gas (GHG) Portland cement (PC) in cement-based materials with these ashes. Specifically, rice hull ash (RHA), wheat straw ash (WSA), and sugarcane bagasse ash (SBA) were treated to mineralize carbon, and their experimental carbon content was compared to modeled potential carbonation. To understand changes in the cement-based storage materials, mortars made with CO2-treated WSA and RHA were experimentally compared to PC-only mortars and mortars made with ashes without prior CO2 treatment. Life cycle assessment methodology was applied to understand potential reductions in GHG emissions. The modeled carbonation was ∼18 g-CO2/kg-RHA and ∼180 g-CO2/kg-WSA. Ashes oxidized at 500 °C had the largest measured carbon content (5.4 g-carbon/kg-RHA and 35.3 g-carbon/kg-WSA). This carbon appeared to be predominantly residual from the biomass. Isothermal calorimetry showed RHA-PC pastes had similar heat of hydration to PC-pastes, while WSA-PC pastes exhibited an early (at ∼1.5 min) endothermic dip. Mortars with 5 % and 15 % RHA replacement had 1–12 % higher compressive strength at 28 days than PC-only mortars, and milled WSA mortars with 5 % replacement had 3 % higher strength. A loss in strength was noted for the milled 15 % WSA, the CO2-treated 5 %, and the 15 % WSA mortars. Modeled reductions in GHG emissions from CO2-treated ashes were, however, marginal (<1 %) relative to the untreated ashes. KW - CO2 sequestration KW - CO2 storage KW - Biomass ash KW - Supplementary cementitious materials KW - Concrete PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-626959 DO - https://doi.org/10.1016/j.biombioe.2025.107772 SN - 1873-2909 VL - 197 SP - 1 EP - 13 PB - Elsevier CY - Amsterdam AN - OPUS4-62695 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Asante, Bright T1 - Optimized mix design and fire resistance of geopolymer recycled aggregate concrete under elevated temperatures N2 - This study investigates the performance of fly ash-based geopolymer recycled aggregate concrete (GRAC) as a sustainable alternative to Ordinary Portland Cement (OPC) concrete, focusing on its compressive strength and behavior under high-temperature exposure (150 ◦C, 300 ◦C, 600 ◦C, and 900 ◦C). The research emphasizes the use of 100 % recycled concrete aggregates as a replacement for natural aggregates, with samples cured at ambient conditions and at 60 ◦C in an oven. Key factors, including water content and curing conditions, were evaluated to determine their influence on compressive strength and thermal stability. Results indicate that water content is the primary factor governing compressive strength, while recycled aggregates contribute to a secondary but notable effect. GRAC maintained up to 65 % of its initial strength after exposure to 600 ◦C, though strength degradation and severe cracking occurred at 900 ◦C. Oven-cured samples showed fewer surface cracks but experienced slightly higher mass loss than room-cured coun-terparts. This study highlights the potential of GRAC as an environmentally friendly material capable of withstanding moderate thermal conditions, providing significant contributions to green construction practices and the reuse of construction and demolition waste. KW - Geopolymer KW - Recycled aggregate concrete KW - Elevated temperature PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-627071 DO - https://doi.org/10.1016/j.cscm.2025.e04401 SN - 2214-5095 VL - 22 SP - 1 EP - 17 PB - Elsevier Ltd. AN - OPUS4-62707 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Baier, Johanna A1 - Ziegert, Christof T1 - DIN 18940 für tragendes Lehmsteinmauerwerk – Potenzial und erste Anwendungserfahrungen N2 - Mit der Veröffentlichung der DIN 18940 Juni 2023 steht in Deutschland eine zeitgemäße Bemessungsgrundlage für tragendes Lehmmauerwerk zur Verfügung, die derzeit europaweit einmalig ist. Während nach bisherigen Vorschriften lediglich zweigeschossige Gebäude mit tragendem Lehmsteinmauerwerk realisierbar waren, ermöglicht die DIN 18940 nun den Einsatz von Lehmsteinmauerwerk in fünfgeschossigen, bis zu 13 m hohen Gebäuden. Das Bemessungskonzept der DIN 18940 lehnt sich an die Grundprinzipien der vereinfachten Berechnungsmethoden für unbewehrte Mauerwerksbauten nach DIN EN 1996-3/NA an und berücksichtigt dabei die materialspezifischen Eigenschaften von Lehmsteinmauerwerk. Anpassungen waren aufgrund der feuchteabhängigen Festigkeits- und Verformungskenngrößen sowie der im Vergleich zu herkömmlichem Mauerwerk geringen Steifigkeit erforderlich. Ein Vergleich mit konventionellem Mauerwerk aus Ziegeln, Porenbeton und Kalksandsteinen zeigt, dass Lehm hinsichtlich Tragfähigkeit und bauphysikalischen Eigenschaften im Bereich der Gebäudeklasse 1-4 konkurrenzfähig ist. Besonders die geringen CO2-Emissionen und die vollständige Rezyklierbarkeit machen Lehmsteinmauerwerk zu einer klimagerechten Alternative. Weiterhin werden erste Projekte vorgestellt, die nach DIN 18940 geplant wurden. Aus den Anwendungserfahrungen werden materialgerechte Entwurfsgrundsätze für Gebäude aus Lehmsteinmauerwerk formuliert. Abschließend zeigen Einblicke in laufende Forschung und zukünftige Entwicklung, wie das Potenzial von Lehmsteinmauerwerk weiter gesteigert werden kann. T2 - LEHM 2024 - 9. Internationale Fachtagung für Lehmbau CY - Weimar, Germany DA - 27.09.2024 KW - Lehmmauerwerk KW - Ökobilanzierung KW - Normung PY - 2024 SP - 1 EP - 8 AN - OPUS4-62030 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schneider, Ronald T1 - Zuverlässigkeitsbasierte Bemessung und Monte Carlo Simulation N2 - Am 19. und 20.11.2024 veranstaltete die BAM und der DGGT AK 2.15 „Zuverlässigkeitsbasierte Methoden in der Geotechnik“ in Zusammenarbeit mit der DGGT-Akademie einen zweitägigen Workshop zur Einführung in die zuverlässigkeitsbasierte Bemessung. Am ersten Tag wurden in einem Short Course die Grundlagen der Zuverlässigkeitsanalyse in der Geotechnik vermittelt, wobei den Teilnehmenden die Möglichkeit geboten wurde, unter Anleitung Aufgaben mit Hilfe geeigneter Software am PC selbstständig zu bearbeiten. In diesem Vortrag wurde die Grundlagen der zuverlässigkeitsbasierten Bemessung und die Monte Carlo Simulation zur Abschätzung der Versagenswahrscheinlichkeit dargestellt. T2 - 2. Workshop des DGGT AK 2.15 „Zuverlässigkeitsbasierte Methoden in der Geotechnik“ CY - Berlin, Germany DA - 19.11.2024 KW - Zuverlässigkeitsanalyse KW - Geotechnik KW - Monte Carlo Simulation PY - 2024 AN - OPUS4-61905 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schneider, Ronald A1 - Schwiersch, Niklas T1 - Betrieb und Planung - Ausgewählte Vorteile von Risikoanalysen im Ingenieur- und Wasserbau N2 - Am 19. und 20.11.2024 veranstaltete die BAM und der DGGT AK 2.15 „Zuverlässigkeitsbasierte Methoden in der Geotechnik“ in Zusammenarbeit mit der DGGT-Akademie einen zweitägigen Workshop zur Einführung in die zuverlässigkeitsbasierte Bemessung. Im Rahmen der Vortragsveranstaltung am zweiten Tag wurden zum einen die unterschiedlichen Sicherheits- und Bemessungsphilosophien nach dem bewährten Teilsicherheitskonzept sowie nach dem zuverlässigkeitsbasierten Konzept vorgestellt. Zum anderen werden verschiedene Anwendungen zuverlässigkeitsbasierter Verfahren aus der Ingenieurpraxis und Wissenschaft präsentiert. In diesem Vortrag wurden aus Sicht des Ingenieur- und Wasserbaus Vorteile von Risikoanalysen u. a. für die Planung von Inspektionszyklen, die Ursachenforschung im Versagensfall und die Konzeption von Hochwasserrisikomanagement-Maßnahmen präsentiert. T2 - 2. Workshop des DGGT AK 2.15 „Zuverlässigkeitsbasierte Methoden in der Geotechnik“ CY - Berlin, Germany DA - 19.11.2024 KW - Risikoanalyse KW - Offshore-Strukturen KW - Hochwasserschutz PY - 2024 AN - OPUS4-61906 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Lehmann, Jens T1 - Vorstellung des GfKORR Arbeitskreises Atmosphärische Korrosion N2 - Es wird ein Überblick zu den Zielen Aktivitäten und Schwerpunktthemen des GfKORR Arbeitskreises Atmosphärische Korrosion gegeben. Hintergründe zu den einzelnen Schwerpunkten Pflege des Sachstandes, Vernetzung und Output sollen einen Einblick in die AK Arbeit geben. T2 - Gemeinschaftssitzung GfKORR Arbeitskreise "Korrosionsschutz in der Elektronik und Mikrosystemtechnik" und “Atmosphärische Korrosion” CY - Online Meeting DA - 05.12.2024 KW - Korrosion KW - Experimente KW - Atmosphärische Korrosion PY - 2024 AN - OPUS4-62081 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Baier, Johanna A1 - Ziegert, Christof T1 - DIN 18940 für tragendes Lehmsteinmauerwerk – Potenzial und erste Anwendungserfahrungen N2 - Mit der Veröffentlichung der DIN 18940 Juni 2023 steht in Deutschland eine zeitgemäße Bemessungsgrundlage für tragendes Lehmmauerwerk zur Verfügung, die derzeit europaweit einmalig ist. Während nach bisherigen Vorschriften lediglich zweigeschossige Gebäude mit tragendem Lehmsteinmauerwerk realisierbar waren, ermöglicht die DIN 18940 nun den Einsatz von Lehmsteinmauerwerk in fünfgeschossigen, bis zu 13 m hohen Gebäuden. Das Bemessungskonzept der DIN 18940 lehnt sich an die Grundprinzipien der vereinfachten Berechnungsmethoden für unbewehrte Mauerwerksbauten nach DIN EN 1996-3/NA an und berücksichtigt dabei die materialspezifischen Eigenschaften von Lehmsteinmauerwerk. Anpassungen waren aufgrund der feuchteabhängigen Festigkeits- und Verformungskenngrößen sowie der im Vergleich zu herkömmlichem Mauerwerk geringen Steifigkeit erforderlich. Ein Vergleich mit konventionellem Mauerwerk aus Ziegeln, Porenbeton und Kalksandsteinen zeigt, dass Lehm hinsichtlich Tragfähigkeit und bauphysikalischen Eigenschaften im Bereich der Gebäudeklasse 1-4 konkurrenzfähig ist. Besonders die geringen CO2-Emissionen und die vollständige Rezyklierbarkeit machen Lehmsteinmauerwerk zu einer klimagerechten Alternative. Weiterhin werden erste Projekte vorgestellt, die nach DIN 18940 geplant wurden. Aus den Anwendungserfahrungen werden materialgerechte Entwurfsgrundsätze für Gebäude aus Lehmsteinmauerwerk formuliert. Abschließend zeigen Einblicke in laufende Forschung und zukünftige Entwicklung, wie das Potenzial von Lehmsteinmauerwerk weiter gesteigert werden kann. T2 - LEHM 2024 - 9. Internationale Fachtagung für Lehmbau CY - Weimar, Germany DA - 27.09.2024 KW - Lehmmauerwerk KW - Ökobilanzierung KW - Normung PY - 2024 SP - 1 AN - OPUS4-62034 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Saif-Ur-Rehman, Saif-Ur-Rehman T1 - Failure prediction during 3D concrete printing: a numerical simulation aproach N2 - 3D concrete printing is a technology that promises to bring digitalization in the construction phase of E&C industry. It brings automation in the construction process by removing the need for formwork and providing a much better geometrical flexibility in terms of construction of complex structures. However, owing to the novelty of the technology, it brings an added complexity compared to traditional methods which needs to be studied. As many parameters are involved in the process, a detailed knowledge about the parameters and their influence on the mechanical behaviour of the object being printed is limited. Because of this, these parameters are commonly determined using a trial-and-error approach which can lead to unforeseen failure during the printing process. A systematic approach to determine the optimal set of parameters is required so that the mechanical behaviour of the (freshly) printed concrete can be controlled. This work is aimed towards achieving a better understanding of the various parameters involved in the 3DCP process and how they affect the mechanical behaviour of the object being printed using a modeling and simulation approach. Additionally, it seeks to develop optimization strategies and process control methods based on numerical models. A physics based numerical model is developed with the focus on capturing the correct material response using von-mises plasticity model with non-linear isotropic hardening. An objective stress rate is used to account for geometric non-linearity. Time dependent material parameters are used to replicate the aging effect of concrete. A density-based step by step layer activation approach is used for the structural model to mimic the layer-by-layer printing process. Both failure modes namely plastic collapse and elastic buckling are observed qualitatively. Model calibration and quantitative comparison with experimental results are planned for future work. Furthermore, development of optimization strategies and building a digital twin of the process using the developed model and sensor data from the printer are also planned. T2 - Additive Manufactured Concrete Structures 2024 CY - Naples, Italy DA - 15.07.2024 KW - 3D Concrete Printing KW - Material Modeling KW - Simulation PY - 2024 AN - OPUS4-62088 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Costa, Giancarlo A1 - Thöns, Sebastian A1 - Limongelli, Maria Pina A1 - Piscini, Andrea T1 - Value of information‐driven innovation in Gerber saddles monitoring N2 - AbstractInnovation plays a crucial role in shaping technological, economic, and social progress in modern societies. In the realm of bridge integrity management, the development and diffusion of technologies to acquire information can significantly enhance industries' safety and functionality capabilities. Among the most widely diffused bridge types in Europe and North America, Gerber bridges are particularly susceptible to deterioration over time. Gerber saddles are typically not instrumented and are checked only through visual inspections. This paper introduces the metric of the Value of Information for Innovation to estimate the benefit associated with introducing an established technology in a new market of application. Herein, the operational value of implementing microelectromechanical inclinometers in the integrity management of Gerber saddles is quantified for the specific case of a bridge in northern Italy. Microelectromechanical systems companies may use these results to optimally select the technology price, investigate diverse market strategies, and optimize sensor arrangement. KW - Gerber saddles KW - Innovation KW - MEMs KW - Sensor optimization KW - Value of Information PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-627853 DO - https://doi.org/10.1002/suco.202400951 SN - 1751-7648 SP - 1 EP - 16 PB - Wiley AN - OPUS4-62785 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - THES A1 - Chaves Spoglianti de Souza, Roberto T1 - Sensitivity Analyses of Probabilistic Thermo-Mechanical Fire Safety Assessment of Tunnel Linings N2 - Fire safety structural analyses contain uncertainties related to the mechanical aspects, such as compressive strength and tensile strength, and the thermal aspects, such as conductivity, specific heat and fire loads. The uncertainties related to the mechanical aspects are explicitly considered by the applicable standards. However, the uncertainties related to the conductivity and specific heat are implicitly considered by the standards, while the uncertainties related to the fire loads are only considered in the German National Annex of the Eurocode 1991-1-2. Nevertheless, considering the severe nature of tunnel fires, these uncertainties must be incorporated into the design. The complexity of the stresses in a tunnel lining in fire can be determined by a probabilistic thermo-mechanical analysis as proposed in the methodology presented in this work. The methodology presented here to investigate the influence of thermal parameters on the fire safety of concrete structures in tunnels is based on the thermo-mechanical finite element analysis. The methodology includes the design of experiments executed by a Correlation Latin Hypercube Sampling. This work includes three case studies to illustrate the use of the proposed methodology. The second and the third studies contain reliability analyses to evaluate the probabilities of failure. The first case study uses an analytical thermo-mechanical analysis based on the 500 °C isotherm method. It considers the uncertainties related to the thermal and mechanical properties of the concrete, the soil load, and the temperatures described by the standard temperature-time curve. The results demonstrate the importance of incorporating the characteristic values of conductivity and specific heat in the semi-probabilistic structural fire design. The probability of failure is Pf = 3.1 × 10−3. The second case study is a probabilistic thermo-mechanical analysis of tunnels using the standard temperature-time curve. It considers the uncertainties related to the thermal and mechanical properties of the concrete, the soil load, and temperature. The probability of failure is Pf = 0.06. The third case study is a probabilistic thermo-mechanical analysis of the tunnel using natural fire calculated with CFast. It considers the uncertainties related to the thermal and mechanical properties of the concrete, the soil load, and the fire load. The probability of failure is Pf = 0.08. Although the natural fire in the third study results in higher temperatures than the standard fire in the second study, the difference between the failure probabilities of both case studies is smaller than expected. The reason for the small difference is probably that the effects due to the higher temperatures are compensated by the decay phase of the natural fire. The reliability assessments of both the second and the third case study show that the investigated structures do not meet the reliability requirements derived from the EN 1990 standard. Therefore, the structures would either need to be redesigned or more protective methods would need to be provided, such as the thermal boards or sprinklers. The conductivity, specific heat, and fire load are the parameters that correlate to the results the most. For the tunnel structural fire design, the following safety factors are recommended based on this work: γfi = 1.76 for the conductivity, γfi = 0.31 for the specific heat, and γfi = 1.8 for the fire load. Given the range of results of the fire safety analyses, the inclusion of the uncertainties is demonstrated to be necessary. The choice of failure criterion has a significant influence on the probability of failure and is, therefore, a critical step in the safety analysis. For the tunnel fire, the model must be improved to accurately account for the fast heating rate and the cooling phase of tunnel fires. KW - Tunnel Fires KW - Uncertainties of Structural Fire Safety KW - Tunnel Linings KW - Fire Safety Assessment PY - 2021 SP - 1 EP - 186 PB - Fakultät Architektur, Bauingenieurwesen und Umweltwissenschaften der Technischen Universität Carolo-Wilhelmina zu Braunschweig CY - Braunschweig AN - OPUS4-62967 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Zhang, Kun A1 - Lin, Chang A1 - Pan, Lisha T1 - Effect of sisal fibers on the rheology of cement paste plasticized by polycarboxylate superplasticizer N2 - Sisal fibers (SF) and polycarboxylate superplasticizers (PCE) contribute to the sustainable development of cementitious materials by improving and optimizing their hardening properties. In this study, the impact of SF and PCE on the workability of cement pastes was investigated. The workability was evaluated through spreading diameter, yield stress, and plastic viscosity measurements, and the adsorption behavior of PCE was analyzed. The results showed that the introduction of SF had a negative effect on the workability of PCE plasticized cement pastes, reducing flowability and increasing yield stress and plastic viscosity, regardless of aspect ratio or dosage. A contact angle tester and a scanning electron microscope (SEM) were employed to examine the surface properties of SF. The mechanism behind this interaction of cement-PCE-SF was explored and found to be due to the rough surface of SF, which increased the consumption of PCE, and the formation of hydrogen bonds between PCE and SF. Additionally, PCE modified the interfacial structure between SF and the cement matrix, strengthening the relationship between the different phases. These findings provide new insights into the modification of fiber-reinforced cementitious materials. KW - Cement paste KW - Polycarboxylate KW - Flowability KW - Rheological KW - Sisal fiber (SF) KW - Adsorption PY - 2024 DO - https://doi.org/10.1061/jmcee7.mteng-16789 SN - 0899-1561 VL - 36 IS - 3 SP - 1 EP - 12 PB - American Society of Civil Engineers (ASCE) CY - Reston, VA AN - OPUS4-62893 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Geburtig, Anja A1 - Wachtendorf, Volker A1 - Trubiroha, P. T1 - Simulationsdaten zur photooxidativen Beanspruchung an verschiedenen geografischen Freibewitterungs-Standorten N2 - Freibewitterungen weisen grundsätzlich eine hohe Variabilität der jeweiligen Intensität der Beanspruchungsparameter auf; sie sind nicht einfach wiederholbar. Um dennoch die Ergebnisse einer Beanspruchung vergleichen zu können, ist eine aussagekräftige Charakterisierung der Freibewitterung wichtig. Traditionell werden Daten bekannter Einflussgrößen wie Globalstrahlung, Temperatur oder Feuchtewerte herangezogen. Obwohl man weiß, dass diese Größen an den exponierten Oberflächen wechselwirken und kombiniert als Mikroklima Einfluss auf Degradationsprozesse nehmen, werden schon aus Praktikabilitätsgründen diese separat als klimatische Messgrößen angegeben. Die Aussagekraft dieser Daten ist mäßig. Ziel dieses Beitrags ist es, die Aussagekraft und damit Vergleichbarkeit zu erhöhen, indem diese Messdaten als Stundendaten zu Wirkintegralen vorverarbeitet und jahresweise akkumuliert werden. Betrachtet wird dafür der Prozess der Photooxidation, da dieser Alterungs-mechanismus bei allen Kunststoffen auftritt. Für eine einfache Modellierung wird die wirksame UV-Bestrahlung, gewichtet mit einer Arrhenius-abhängigen Ober¬flächen-temperatur (TOF), über den Beanspruchungszeitraum von hier je einem Jahr akkumuliert. Die Idee einer solchen Messgröße für photooxidative Ober¬flächen¬alterung wurde bereits vorgestellt [1]. Dort wurde ein Gerät vor¬geschlagen, mit dem dieser Wert für verschieden absorbierende Oberflächen für die Dauer einer Exposition akkumuliert wird, und ergänzend eine Abschätzung der Betauungs¬zeiten dieser Referenz-Oberflächen erfolgen könnte. Hier soll es um eine rechnerisch generierte Zusammenstellung dieser photo¬oxidativen 1-Jahres-Alterungswerte für verschiedene Standorte gehen. Ein Temperaturfaktor erfasst dabei den Einfluss der Strahlungserwärmung auf eine weiße, graue bzw. schwarze Referenzoberflächen, spiegelt also die Kopplung von solarer Strahlung und Temperatur wider [1]. Ermittelt wird er aus Stunden¬daten der Globalstrahlung und der Lufttemperatur. Die spektrale Wirkung wird aus Sonnenhöhenständen entsprechend der geografischen Breite mit Hilfe der FastRT-Oberfläche [2] als PiT·h-Wert abgeschätzt [3]. Anhand der errechneten Jahreswerte können die Schweregrade der photo¬oxidativen Beanspruchung an den verschiedenen Standorten unmittelbar verglichen werden. Die gezeigten Simulationsdaten für ein solches „elektronisches Referenzmaterial“ für photooxidative Degradation zeigen die prinzipielle Möglichkeit einer Kartografierung solcher Daten auf. T2 - 53. Jahrestagung der GUS CY - Stutensee-Blankenloch, Germany DA - 26.03.2025 KW - Polymer 3R, UV, Bestrahlung, Bewitterung PY - 2025 SN - 978-3-9826129-2-8 VL - 53 SP - 19 EP - 28 PB - Gesellschaft für Umweltsimulation e.V. CY - 76327 Pfinztal (Berghausen) AN - OPUS4-62902 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Liehr, Alexander A1 - Dingel, Kristina A1 - Kottke, Daniel A1 - Degener, Sebastian A1 - Meier, David A1 - Sick, Bernhard A1 - Niendorf, Thomas T1 - Data selection strategies for minimizing measurement time in materials characterization N2 - Every new material needs to be assessed and qualified for an envisaged application. A steadily increasing number of new alloys, designed to address challenges in terms of reliability and sustainability, poses significant demands on well-known analysis methods in terms of their efficiency, e.g., in X-ray diffraction analysis. Particularly in laboratory measurements, where the intensities in diffraction experiments tend to be low, a possibility to adapt the exposure time to the prevailing boundary conditions, i.e., the investigated microstructure, is seen to be a very effective approach. The counting time is decisive for, e.g., complex texture, phase, and residual stress measurements. Traditionally, more measurement points and, thus, longer data collection times lead to more accurate information. Here, too short counting times result in poor signal-to-background ratios and dominant signal noise, respectively, rendering subsequent evaluation more difficult or even impossible. Then, it is necessary to repeat experiments with adjusted, usually significantly longer counting time. To prevent redundant measurements, it is state-of-the-art to always consider the entire measurement range, regardless of whether the investigated points are relevant and contribute to the subsequent materials characterization, respectively. Obviously, this kind of approach is extremely time-consuming and, eventually, not efficient. The present study highlights that specific selection strategies, taking into account the prevailing microstructure of the alloy in focus, can decrease counting times in X-ray energy dispersive diffraction experiments without any detrimental effect on data quality for the subsequent analysis. All relevant data, including the code, are carefully assessed and will be the basis for a widely adapted strategy enabling efficient measurements not only in lab environments but also in large-scale facilities. KW - Materials characterization KW - Machine learning KW - X-ray diffraction KW - Measurement optimization PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-630831 DO - https://doi.org/10.1038/s41598-025-96221-1 SN - 2045-2322 VL - 15 IS - 1 SP - 1 EP - 12 PB - Springer Science and Business Media LLC AN - OPUS4-63083 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Merz, P. A1 - Dombrowski, M. A1 - Loutfi, J. A1 - Zeitler, B. T1 - Building acoustic analysis of doubly curved beam-like shell floors made of CFRP prestressed concrete and its integration into an interdisciplinary optimisation tool N2 - An optimisation tool was developed to reduce the embodied carbon of floor systems. The considered system consists of a doubly curved beam-like shell made of carbon-fibre-reinforced polymer (CFRP) prestressed concrete and an infill layer. The thin-walled design of the system makes it susceptible to sound excitation. Therefore, the optimisation tool considers the static ultimate and serviceability limit states and the sound insulation aspect. Due to a lack of experience with the building acoustic properties of this floor system, it is, in practice, often simplified as a homogeneous floor. This paper aims to investigate its acoustic behaviour in more detail using numerical simulations and to integrate the gained knowledge into the optimisation tool. For this purpose, a simulation concept is set up and implemented. Simulations are carried out for different combinations of geometry and material parameters of the floor system. The data obtained is summarised into linear regression equations that estimate the weighted airborne sound reduction index and the weighted equivalent normalised impact sound pressure level of the system. The optimisation results based on these equations show a clear difference compared to those based on the above-mentioned simplified approach. T2 - IASS 2024 Annual Symposium: Redefining the Art of Structural Design CY - Zurich, Switzerland DA - 26.08.2024 KW - Building acoustic simulation KW - Impact sound pressure level KW - Airborne sound reduction index KW - Doubly curved beam-like shells KW - CFRP KW - Interdisciplinary optimisation PY - 2024 SP - 2752 EP - 2761 PB - International Association for Shell and Spatial Structures (IASS) CY - Zürich, Schweiz AN - OPUS4-63089 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Liao, Chun-Man ED - Zhang, Jian T1 - Modal and Wave Propagation Analysis of Vibration Tests on a Laboratory Building Model Before and After Damage N2 - Weakened structural stiffness is often a consequence of building damage, particularly after severe events such as earthquakes, where compromised structural performance can pose significant risks. To prevent immediate structural failure, an early warning system is essential, which requires inspection of local components. This research aims to achieve that by exploring the wave propagation analysis method, specifically seismic interferometry. Previous studies have applied this method to building structures, treating them as homogeneous layers of grouped floors. By analyzing the wave travel time along the height of these layers, the fundamental period of the building was estimated. However, this approach did not account for local damage or the variability of structural components, similar to the limitations of vibration‐based damage detection methods, which mainly identify global changes. Thus, the goal of this paper is to improve structural health monitoring by examining the sensitivity of wave screening, bridging the gap between nondestructive testing and vibration‐based damage detection. A half‐scale, seven‐story building model, characterized by vertical stiffness irregularity and transverse plan asymmetry, was tested in a laboratory setting. Two vertical sensor arrays were placed near corner columns of different sizes, representing both strong and weak structural areas. These arrays recorded floor accelerations in three directions. The study confirmed the effectiveness of wave propagation analysis for detecting damage along the sensor arrays before and after the earthquake. A transmissibility damage indicator was used to correlate changes in wave velocity, providing a quantitative assessment of damage levels along the wave propagation path. KW - Damage location KW - Laboratory test KW - Soft story KW - Stifness irregular structure KW - Structural health monitoring PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-624931 DO - https://doi.org/10.1155/stc/3453150 SN - 1545-2263 VL - 2025 IS - 1 SP - 1 EP - 17 PB - John Wiley & Sons Ltd. AN - OPUS4-62493 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - He, Yuxiang A1 - Robens-Radermacher, Annika A1 - Noda, S. A1 - Wolf, Christoph A1 - Unger, Jörg F. A1 - Mai, I. ED - Ferrara, L. ED - Muciaccia, G. ED - di Summa, D. T1 - Automated Workflows for Concrete Additive Manufacturing for Design, Optimization, and Fabrication of Parametrized Elements N2 - 3D concrete printing is an innovative new construction technology offering the potential to enable the efficient production of individual structures with less consumption of resources. The technology will mainly shape the future construction philosophy. From the design of a structure to the printed component, many individual steps based on different software are required, which must be repeated for each new or even slightly changed design. The geometry of the structure is created in a CAD program. The print path is defined in slicer software leading to the machine code for the printer to print the structure. A numerical model of the printed structure makes optimization in design and fabrication possible, by predicting the behaviour of the structure and reducing the number of test prints and costs. For that, additional steps like meshing the design and running a simulation are required. In order to work efficiently, an automated workflow is necessary, which runs all of the individual steps without interacting with each software program. Furthermore, changes in parameters or the exchange of parts (different designs or printers) must be simple. One way to develop such an automated workflow is presented within this paper. The interfaces are defined in a way that allows running the full chain of tools as well as individual steps. The workflow is demonstrated based on the example of a parametrized wall element for extrusion-based concrete. Furthermore, a test series of cubes is printed, and the influence of different infill structures is numerically and experimentally compared. T2 - RSCC 2024 - RILEM Spring Convention and Conference 2024 CY - Milano, Italy DA - 07.04.2024 KW - 3D concrete printing KW - Automation KW - Workflow KW - Innovative technologies PY - 2024 SN - 978-3-031-70280-8 SN - 978-3-03170281-5 SN - 978-3-031-70283-9 DO - https://doi.org/10.1007/978-3-031-70281-5_28 SN - 2211-0844 SN - 2211-0852 N1 - Serientitel: RILEM Bookseries – Series title: RILEM Bookseries VL - 56 IS - 2 SP - 247 EP - 254 PB - Springer CY - Cham AN - OPUS4-61608 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Titscher, Thomas A1 - van Dijk, T. A1 - Kadoke, Daniel A1 - Robens-Radermacher, Annika A1 - Herrmann, Ralf A1 - Unger, Jörg F. T1 - Bayesian model calibration and damage detection for a digital twin of a bridge demonstrator N2 - Using digital twins for decision making is a very promising concept which combines simulation models with corresponding experimental sensor data in order to support maintenance decisions or to investigate the reliability. The quality of the prognosis strongly depends on both the data quality and the quality of the digital twin. The latter comprises both the modeling assumptions as well as the correct parameters of these models. This article discusses the challenges when applying this concept to realmeasurement data for a demonstrator bridge in the lab, including the data management, the iterative development of the simulation model as well as the identification/updating procedure using Bayesian inference with a potentially large number of parameters. The investigated scenarios include both the iterative identification of the structural model parameters as well as scenarios related to a damage identification. In addition, the article aims at providing all models and data in a reproducibleway such that other researcher can use this setup to validate their methodologies. KW - Damage detection KW - Finite element analysis KW - Load identification KW - Model updating KW - Estimation KW - System identification KW - Variational Bayesian statistics PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-574496 DO - https://doi.org/10.1002/eng2.12669 SN - 2577-8196 SP - 1 EP - 27 PB - Wiley CY - Hoboken, NJ AN - OPUS4-57449 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Diercks, Philipp A1 - Veroy, K. A1 - Robens-Radermacher, Annika A1 - Unger, Jörg F. T1 - Multiscale modeling of linear elastic heterogeneous structures via localized model order reduction N2 - In this paper, a methodology for fine scale modeling of large scale linear elastic structures is proposed, which combines the variational multiscale method, domain decomposition and model order reduction. The influence of the fine scale on the coarse scale is modelled by the use of an additive split of the displacement field, addressing applications without a clear scale separation. Local reduced spaces are constructed by solving an oversampling problem with random boundary conditions. Herein, we inform the boundary conditions by a global reduced problem and compare our approach using physically meaningful correlated samples with existing approaches using uncorrelated samples. The local spaces are designed such that the local contribution of each subdomain can be coupled in a conforming way, which also preserves the sparsity pattern of standard finite element assembly procedures. Several numerical experiments show the accuracy and efficiency of the method, as well as its potential to reduce the size of the local spaces and the number of training samples compared to the uncorrelated sampling. KW - Multiscale methods KW - Variational multiscale method KW - Localized model order reduction KW - Domain decomposition methods PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-580671 DO - https://doi.org/10.1002/nme.7326 SN - 0029-5981 SP - 1 EP - 23 PB - Wiley online library AN - OPUS4-58067 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Otto, Peter A1 - de Lorenzis, L. A1 - Unger, Jörg F. T1 - Explicit dynamics in impact simulation using a NURBS contact interface N2 - In this paper, the impact problem and the subsequent wave Propagation are considered. For the contact discretization an intermediate non-uniform rational B-spline (NURBS) layer is added between the contacting finite element bodies, which allows a smooth contact formulation and efficient element-based integration. The impact event is ill-posed and requires a regularization to avoid propagating stress oscillations. A nonlinear mesh-dependent penalty regularization is used, where the stiffness of the penalty regularization increases upon mesh refinement. Explicit time integration methods are well suited for wave propagation problems, but are efficient only for diagonal mass matrices. Using a spectral element discretization in combination with a NURBS contact layer the bulk part of the mass matrix is diagonal. KW - Explicit dynamics KW - Impact simulation KW - Isogeometric analysis KW - mortar method KW - spectral elements PY - 2019 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-506041 DO - https://doi.org/10.1002/nme.6264 VL - 121 IS - 6 SP - 1248 EP - 1267 PB - Wiley Online Libary AN - OPUS4-50604 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Robens-Radermacher, Annika A1 - Held, Felix A1 - Coelho Lima, Isabela A1 - Titscher, Thomas A1 - Unger, Jörg F. T1 - Efficient identification of random fields coupling Bayesian inference and PGD reduced order model for damage localization N2 - One of the main challenges regarding our civil infrastructure is the efficient operation over their complete design lifetime while complying with standards and safety regulations. Thus, costs for maintenance or replacements must be optimized while still ensuring specified safety levels. This requires an accurate estimate of the current state as well as a prognosis for the remaining useful life. Currently, this is often done by regular manual or visual inspections within constant intervals. However, the critical sections are often not directly accessible or impossible to be instrumented at all. Model‐based approaches can be used where a digital twin of the structure is set up. For these approaches, a key challenge is the calibration and validation of the numerical model based on uncertain measurement data. The aim of this contribution is to increase the efficiency of model updating by using the advantage of model reduction (Proper Generalized Decomposition, PGD) and applying the derived method for efficient model identification of a random stiffness field of a real bridge.” KW - Model reduction KW - Model updating KW - Proper generalized decomposition KW - Random field KW - Variational Bayesian Inference PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-521275 DO - https://doi.org/10.1002/pamm.202000063 VL - 20 IS - 1 SP - e202000063 PB - Wiley Online Libary AN - OPUS4-52127 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schönsee, Eric A1 - Hüsken, Götz A1 - Jeyifous, Olubunmi Anthony A1 - Mezhov, Alexander A1 - Strangfeld, Christoph T1 - Calculating rheological properties of fresh mortar for additive manufacturing based on experimental, multi-sensor data N2 - Additive manufacturing of concrete structures is a novel and emerging technology. Freecontouring in civil engineering, which allows for entirely new designs, is a significant advantage. Inthe future, lower construction costs are expected with increased construction speeds and decreasingrequired materials and workers. However, architects and civil engineers rely on a certain quality ofexecution to fulfil construction standards. Although several techniques and approaches demonstratethe advantages, quality control during printing is highly challenging and rarely applied. Due to thecontinuous mixing process commonly used in 3D concrete printing, it is impossible to exclude varia-tions in the dry mixture or water content, and a test sample cannot be taken as a representative samplefor the whole structure. Although mortar properties vary only locally, a defect in one layer duringprinting could affect the entire integrity of the whole structure . Therefore, real-time process monitor-ing is required to record and document the printing process.At the Bundesanstalt für Materialforschung und -prüfung (BAM) a new test rig for the additive man-ufacturing of concrete is built. The primary purpose is measuring and monitoring the properties of amortar during the printing process.The following study investigates an approach for calculating yield stress and plastic viscosity based onexperimentally recorded pressure data. The calculations assume that fresh mortar behaves as a Bing-ham fluid and that the Buckingham-Reiner-equation is applicable. A test setup consisting of rigid pipeswith integrated pressure sensors at different positions is utilized.Monitoring the printing process with different sensors is crucial for the quality control of an ongoingprocess. T2 - Non-Traditional Cement and Concrete 2023 Conference CY - Brno, Czech Republic DA - 25.06.2023 KW - 3DCP KW - Monitoring KW - Additive manufacturing KW - Rheology KW - Bingham fluid KW - Concrete printing PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-598179 DO - https://doi.org/10.4028/p-EV4gPv SN - 1662-0356 VL - 145 SP - 131 EP - 139 PB - Trans Tech Publications CY - Baech AN - OPUS4-59817 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Strobl, Dominic A1 - Unger, Jörg F. A1 - Ghnatios, C. A1 - Robens-Radermacher, Annika T1 - PGD in thermal transient problems with a moving heat source: A sensitivity study on factors affecting accuracy and efficiency N2 - Thermal transient problems, essential for modeling applications like welding and additive metal manufacturing, are characterized by a dynamic evolution of temperature. Accurately simulating these phenomena is often computationally expensive, thus limiting their applications, for example for model parameter estimation or online process control. Model order reduction, a solution to preserve the accuracy while reducing the computation time, is explored. This article addresses challenges in developing reduced order models using the proper generalized decomposition (PGD) for transient thermal problems with a specific treatment of the moving heat source within the reduced model. Factors affecting accuracy, convergence, and computational cost, such as discretization methods (finite element and finite difference), a dimensionless formulation, the size of the heat source, and the inclusion of material parameters as additional PGD variables are examined across progressively complex examples. The results demonstrate the influence of these factors on the PGD model’s performance and emphasize the importance of their consideration when implementing such models. For thermal example, it is demonstrated that a PGD model with a finite difference discretization in time, a dimensionless representation, a mapping for a moving heat source, and a spatial domain non-separation yields the best approximation to the full order model. KW - Additive manufacturing KW - Mapping for unseparable load KW - Model order reduction (MOR) KW - Thermal transient problem KW - Sensitivity analysis KW - Proper generalized decomposition (PGD) PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-598001 DO - https://doi.org/10.1002/eng2.12887 VL - 6 IS - 11 SP - 1 EP - 22 PB - John Wiley & Sons Ltd. CY - Berlin AN - OPUS4-59800 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Strangfeld, Christoph A1 - Stolpe, Heiko A1 - Wiehle, Philipp T1 - Moisture diffusion affected by the Knudsen effect in temporal changing pore networks N2 - Almost all building materials in civil engineering have an open porosity and interact with or are affected by the environmental conditions. Structures might suffer from effects such as moisture adsorption, carbonation, corrosion, penetration of salt ions and chemical substances, etc. In the hygroscopic range, these processes are mostly driven by diffusion. Due to the confinement of small pores (< 1 µm), the Knudsen effect reduces the molecular diffusion. This reduction can become more significant in case of temporal changing pore systems because of physisorption of water vapor, carbonation, or chemisorption. In this study, unstabilised earth blocks and earth masonry are investigated. In a first step, the pore size distribution of the blocks is measured and sorption isotherms are recorded in experiments. Besides the ordinary physisorption, the involved clay minerals undergo swelling or shrinking due to chemisorption. The following two effects must be considered: first, the reduction of the available pore space by the adsorbed water layer. For this, the Hillerborg sorption theory is used, which is a combination of the well-known Brunauer-Emmett-Teller sorption theory and the Kelvin equation. This allows the computation of adsorbed water layers even in curved pore geometries. Second, the variation of the initial pore size distribution due to chemisorption needs to be modelled. Based on these two models, the effective diffusion coefficient can be predicted. For validation, arrays of relative humidity sensors were embedded into a free-standing earth masonry wall. This monitoring was carried out over more than a year to have a broad variety of environmental conditions and was located in Berlin, Germany. The prediction of the effective diffusion coefficient can also be transferred to other processes and allows the investigation of materials having temporarily changing pore systems. Examples are the carbonation of cementitious materials, alkali silica reaction, calcium leaching of long-lasting structures, etc. This effect becomes most prominent in the meso-pore range and might alter the effective diffusion coefficient by more than 100 %. T2 - 4th International Congress on Materials & Structural Stability CY - Rabat, Morocco DA - 08.03.2023 KW - Earth masonry KW - Material moisture KW - Molecular diffusion KW - Chemisoprtion KW - Knudsen effect KW - Physisorption PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-571391 SP - 1 EP - 8 PB - RILEM CY - Champs-sur-Marne AN - OPUS4-57139 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Diercks, Philipp A1 - Gläser, Dennis A1 - Lünsdorf, Ontje A1 - Selzer, Michael A1 - Flemisch, Bernd A1 - Unger, Jörg F. T1 - Evaluation of tools for describing, reproducing and reusing scientific workflows N2 - In the field of computational science and engineering, workflows often entail the application of various software, for instance, for simulation or pre- and postprocessing. Typically, these components have to be combined in arbitrarily complex workflows to address a specific research question. In order for peer researchers to understand, reproduce and (re)use the findings of a scientific publication, several challenges have to be addressed. For instance, the employed workflow has to be automated and information on all used software must be available for a reproduction of the results. Moreover, the results must be traceable and the workflow documented and readable to allow for external verification and greater trust. In this paper, existing workflow management systems (WfMSs) are discussed regarding their suitability for describing, reproducing and reusing scientific workflows. To this end, a set of general requirements for WfMSs were deduced from user stories that we deem relevant in the domain of computational science and engineering. On the basis of an exemplary workflow implementation, publicly hosted at GitHub (https://github.com/BAMresearch/NFDI4IngScientificWorkflowRequirements), a selection of different WfMSs is compared with respect to these requirements, to support fellow scientists in identifying the WfMSs that best suit their requirements. KW - FAIR KW - Reproducibility KW - Scientific workflows KW - Tool comparison KW - Workflow management PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-584832 DO - https://doi.org/10.48694/inggrid.3726 VL - 1 IS - 1 SP - 1 EP - 27 AN - OPUS4-58483 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Mezhov, Alexander A1 - Kulisch, D. A1 - Goncharov, A. A1 - Zhutovsky, S. T1 - A Comparative Study of Factors Influencing Hydration Stoppage of Hardened Cement Paste N2 - There is no consensus on which hydration stoppage method is optimal to preserve the microstructure and mineral composition of samples, especially considering the specific aspects of different testing methods, such as TGA, MIP, or XRD. This paper presents a quantitative comparison between the most popular hydration stoppage strategies and parameters such as the sample piece size, the soaking time in a solvent, and the type, as examined on cement paste hydrated for 7 days. It was found that the carbonation appears either for samples smaller than 2.36 mm and bigger than 4.75 mm or samples soaked in a solvent for longer than 1 h. Fast solvent replacement leads to ettringite diminution and total pore volume increase. Among others, solvent replacement with subsequent gentle heating under a vacuum was found to be the most efficient, whereas it was experimentally demonstrated that isopropyl alcohol stops hydration faster than ethanol and acetone. KW - Hydration stoppage KW - Solvent replacement KW - Soaking time KW - Sample piece size PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-582430 DO - https://doi.org/10.3390/su15021080 VL - 15 IS - 2 SP - 1 EP - 21 PB - MDPI CY - Basel, Switzerland. AN - OPUS4-58243 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Strangfeld, Christoph A1 - Stolpe, Heiko A1 - Wiehle, Philipp T1 - Moisture diffusion affected by the Knudsen effect in temporal changing pore networks N2 - Almost all building materials in civil engineering have an open porosity and interact with or are affected by the environmental conditions. Structures might suffer from effects such as moisture adsorption, carbonation, corrosion, penetration of salt ions and chemical substances, etc. In the hygroscopic range, these processes are mostly driven by diffusion. Due to the confinement of small pores (less than1 µm), the Knudsen effect reduces the molecular diffusion. This reduction can become more significant in case of temporal changing pore systems because of physisorption of water vapor, carbonation, or chemisorption. In this study, unstabilised earth blocks and earth masonry are investigated. In a first step, the pore size distribution of the blocks is measured and sorption isotherms are recorded in experiments. Besides the ordinary physisorption, the involved clay minerals undergo swelling or shrinking due to chemisorption. The following two effects must be considered: first, the reduction of the available pore space by the adsorbed water layer. For this, the Hillerborg sorption theory is used, which is a combination of the well-known Brunauer-Emmett-Teller sorption theory and the Kelvin equation. This allows the computation of adsorbed water layers even in curved pore geometries. Second, the variation of the initial pore size distribution due to chemisorption needs to be modelled. Based on these two models, the effective diffusion coefficient can be predicted. For validation, arrays of relative humidity sensors were embedded into a free-standing earth masonry wall. This monitoring was carried out over more than a year to have a broad variety of environmental conditions and was located in Berlin, Germany. The prediction of the effective diffusion coefficient can also be transferred to other processes and allows the investigation of materials having temporarily changing pore systems. Examples are the carbonation of cementitious materials, alkali silica reaction, calcium leaching of long-lasting structures, etc. These effects are prominent in the meso-pore range and might significantly alter the effective diffusion coefficient. KW - Earth material KW - Material moisture KW - Physisoprtion KW - Chemisorption PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-583811 DO - https://doi.org/10.1016/j.matpr.2023.09.034 SN - 2214-7853 SP - 1 EP - 8 PB - Elsevier Ltd. CY - Amsterdam, Niederlande AN - OPUS4-58381 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Tamsen, Erik T1 - From concrete mixture to structural design an optimization framework to reduce the global warming potential N2 - Concrete has a long history in the construction industry and is currently one of the most widely used building materials. Unfortunately, the concrete industry has a significant impact on the environment by contributing to about 9% of the total anthropogenic greenhouse gas (GHG) emissions. Concrete is a highly complex composite material. However, the main source of concrete's GHG emissions is the cement. This leads to two main strategies when trying to reduce the environmental impact. The first is to reduce the cement within the concrete mix. This can be done by substituting it using additives or increasing the amount of aggregates. Usually this will lead to decreased material properties, like compressive strength or stiffness. The second option is to reduce the amount of required concrete by optimizing the topology of the structure. However, this might require higher compressive strength. In addition, there are other properties like to workability which need to be considered. All in all, this leads to a highly complex optimization problem, which requires the estimation of effective concrete properties, based on the mixture as input to a predictive simulation. We present an automated workflow framework which combines experimental data with simulations, calibrates the simulation and performs the desired optimization. This workflow includes classical FE models, design guidelines based on model codes, as well as data driven methods. The chosen example is a beam, for which the concrete mixture is optimized to reduce GHG emissions. The first step is an estimation of material parameters, based on experimental data. This includes measures of stochastic distribution, allowing the quantification of the quality of the estimated parameters. The second step is the optimization. It takes into account constraints like the loading capacity after 28 days, the maximum allowed temperature during cement hydration and the maximum time till demoulding. The applied models include a Mori-Tanaka-based homogenization method to estimate effective concrete parameters, an FE simulation including the evolution of the concrete compressive strength and stiffness, the temperature field, displacements, and stress. This research shows a way towards a more performance-oriented material design. T2 - M2P 2023 (First International Conference Math 2 Product) CY - Taormina, Italy DA - 30.05.2023 KW - Experimental data KW - Simulations PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-582545 AN - OPUS4-58254 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schnell, A. A1 - Rübner, Katrin A1 - Seher, Julia A1 - Müller, A. A1 - Liebezeit, S. A1 - Fenner, J. A1 - Martin, F. A1 - Pniok, N. T1 - REALight ‐ Leichtgranulate und REA‐Gips aus feinkörnigen sulfatbelasteten Bau‐ und Abbruchabfällen N2 - Ziel des Projekts REALight ist die Entwicklung einer Referenzanlage zur Herstellung von Leichtgranulaten (leichte Gesteinskörnungen) aus Bau‐ und Abbruchabfällen und zur Gipsrückgewinnung. Als Rohstoffe werden bisher ungenutzte oder auf niedrigem Niveau eingesetzte Bau‐ und Abbruchabfälle und industrielle Nebenprodukte verwendet. Als Produkte werden leichte Gesteinskörnungen hergestellt. Die Sulfatabtrennung durch eine thermische Zersetzung bildet die Grundlage für die zusätzliche Gewinnung von Rauchgasentschwefelungs‐Gips (REA‐Gips). Das Projekt wird im Rahmen der Fördermaßnahme „Ressourceneffiziente Kreislaufwirtschaft – Bauen und Mineralische Stoffkreisläufe (ReMin)” gefördert. ReMin ist eine Maßnahme zur Umsetzung des BMBF‐Forschungskonzepts „Ressourceneffiziente Kreislaufwirtschaft” als Teil der BMBF Strategie „Forschung für nachhaltige Entwicklung – FONA”. Ziel der Förderung ist es, den Ausbau der Kreislaufwirtschaft voranzutreiben. Im Mittelpunkt steht dabei die Bauwirtschaft mit ihrer hohen Nachfrage nach Rohstoffen und gleichzeitig großen Mengen an anfallenden mineralischen Abfällen. Am Projekt REALight sind 12 Partner aus verschiedenen Bereichen der Baustoffherstellung und ‐anwendung, Abfallaufbereitung, Verfahrenstechnik sowie Forschung und Entwicklung beteiligt. T2 - 21. Internationale Baustofftagung (ibausil) CY - Weimar, Germany DA - 13.09.2023 KW - Baustoffrecycling KW - Leichtgranulate KW - Gips KW - Leichte Gesteinskörnungen KW - Drehrohrofen KW - Recycling KW - Mauerwerkbruch KW - Infraleichtbeton PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-591708 DO - https://doi.org/10.1002/cepa.2840 SN - 2509-7075 VL - 6 IS - 6 SP - 530 EP - 536 PB - Ernst & Sohn CY - Berlin AN - OPUS4-59170 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Seher, Julia A1 - Rübner, Katrin A1 - Schnell, A. A1 - Hahn, A. A1 - Bruch, I. A1 - Alewell, U. A1 - Vöge, M. A1 - Shafiei, K. A1 - Schumann, G. ED - Pfaff, G. ED - Mertzsch, N. ED - Jeremias, E.-P. T1 - Hydrothermalgranulate – Eine Verwertungsmöglichkeit für Mauerwerkbruch N2 - Im Jahr 2020 fielen in Deutschland rund 220 Millionen Tonnen mineralische Bau- und Abbruchabfälle an, die als Sekundärrohstoffquelle genutzt werden können. Trotz hoher Recyclingquoten wird ein Teil der mineralischen Bau- und Abbruchabfälle immer noch deponiert oder in Anwendungen mit geringen Qualitätsanforderungen eingesetzt, da ein effektives Recycling dieser heterogenen Abfälle recht kompliziert ist. Bauschutt ist ein heterogener, SiO2-reicher Sekundärrohstoff, der sich aus einem Gemisch verschiedener abgebrochener Baumaterialien wie Ziegel, Betonfertigteile, Leichtbeton, Porenbeton, Kalksandsteine, Natursteine, Gips und Mörtel zusammensetzt. Die genaue Zusammensetzung hängt von der Abbruchstelle, der Vorsortierung und der Wiederaufbereitung in der Recyclinganlage ab. Eine direkte Wiederverwendung als rezyklierte Gesteinskörnung ist aufgrund der uneinheitlichen Zusammensetzung und des bis zu 50 %igen Feinanteils nach der mechanischen Aufbereitung nicht zulässig. Eine Möglichkeit, Mauerwerksschutt effektiv zu recyceln, ist die rohstoffliche Verwertung über ein chemisch-hydrothermales Umwandlungsverfahren, das poröse Granulate erzeugt. Durch die Porenstruktur dieser hydrothermal gehärteten Granulate ergeben sich Anwendungsmöglichkeiten als Filter- oder Wasserspeichermaterial, die über den Bausektor hinausgehen. Diese neuartigen Granulate können leichte Gesteinskörnungen natürlichen Ursprungs (z. B. Lavasand, Bimsstein) oder Körner aus natürlichen Rohstoffen (z. B. Blähton) ersetzen. Die neue Recyclingstrategie spart natürliche Ressourcen. Im Vergleich zur Herstellung von Blähton ist der Energieverbrauch wesentlich geringer. Ziel des Verbundprojektes HYTEGRA war die Entwicklung eines Verfahrens zur Herstellung von leichten Gesteinskörnungen aus SiO2- und CaO-reichen Sekundärrohstoffen. Als Rohstoffe wurden Mauerwerksschutt als SiO2-Quelle und Papierasche aus der energetischen Verwertung von Reststoffen der Altpapierverwertung als CaO-Quelle eingesetzt. Der komplette Prozess von der mechanisch-physikalischen Aufbereitung über die Bildung des Grüngranulats bis zur hydrothermalen Härtung wurde entwickelt und im Labormaßstab getestet. Die Anwendungen des hydrothermal gehärteten Granulats als Wasserspeichermaterial für die innere Nachbehandlung von hochfestem Beton, Pflanzensubstrat und Filtermaterial in Bodenfiltern zur Abwasserreinigung wurden untersucht. Der Beitrag gibt einen Überblick über die wichtigsten Ergebnisse des erfolgreich abgeschlossenen Verbundforschungsprojekts HYTEGRA. T2 - Kolloquium des Arbeitskreises “Energie, Mensch und Zivilisation” - Die Energiewende 2.0 Im Fokus: Die Stoffwirtschaft CY - Potsdam, Germany DA - 09.06.2023 KW - Rohstoffliches Recycling KW - Mauerwerkbruch KW - Papierasche KW - leichte Gesteinskörnung KW - poröse Granulate KW - hydrothermale Behandlung PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-593445 UR - https://leibnizsozietaet.de/wp-content/uploads/2023/12/01_SB158-0.pdf SN - 978-3-86464-252-4 DO - https://doi.org/10.53201/SITZUNGSBERICHTE158 SN - 0947-5850 VL - 158 SP - 79 EP - 94 PB - trafo Wissenschaftsverlag CY - Berlin AN - OPUS4-59344 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Agrawal, A. A1 - Tamsen, E. A1 - Unger, Jörg F. A1 - Koutsourelakis, P-S T1 - From concrete mixture to structural design—a holistic optimization procedure in the presence of uncertainties N2 - We propose a systematic design approach for the precast concrete industry to promote sustainable construction practices. By employing a holistic optimization procedure, we combine the concrete mixture design and structural simulations in a joint, forward workflow that we ultimately seek to invert. In this manner, new mixtures beyond standard ranges can be considered. Any design effort should account for the presence of uncertainties which can be aleatoric or epistemic as when data are used to calibrate physical models or identify models that fill missing links in the workflow. Inverting the causal relations established poses several challenges especially when these involve physicsbased models which more often than not, do not provide derivatives/sensitivities or when design constraints are present. To this end, we advocate Variational Optimization, with proposed extensions and appropriately chosen heuristics to overcome the aforementioned challenges. The proposed approach to treat the design process as a workflow, learn the missing links from data/models, and finally perform global optimization using the workflow is transferable to several other materials, structural, and mechanical problems. In the present work, the efficacy of the method is exemplarily illustrated using the design of a precast concrete beam with the objective to minimize the global warming potential while satisfying a number of constraints associated with its load-bearing capacity after 28 days according to the Eurocode, the demolding time as computed by a complex nonlinear finite element model, and the maximum temperature during the hydration. KW - Black-box optimization under uncertainty KW - Mix design KW - Performance oriented design KW - Precast concrete KW - Probabilistic machine learning KW - Sustainable material design PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-615443 DO - https://doi.org/10.1017/dce.2024.18 VL - 5 IS - e20 SP - 1 EP - 32 PB - Cambridge University Press CY - England AN - OPUS4-61544 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Vogler, Nico A1 - Drabetzki, Philipp A1 - Lindemann, Mathias A1 - Kühne, Hans-Carsten T1 - Description of the concrete carbonation process with adjusted depth resolved thermogravimetric analysis N2 - The thermal gravimetric analysis (TG) is a common method for the examination of the carbonation progress of cement-based materials. Unfortunately, the thermal properties of some components complicate the evaluation of TG results. Various hydrate phases, like ettringite (AFt), C-S-H and AFm decompose almost simultaneously in the temperature range up to 200 °C. Additionally, physical bound water is released in the same temperature range. In the temperature range between 450 °C and 600 °C the decomposition of calcium hydroxide and amorphous or weakly bound carbonates takes place simultaneously. Carbonates, like calcite, from limestone powder or other additives may be already contained in the noncarbonated sample material. For this research an attempt was made to minimise the influence of these effects. Therefore, differential curves from DTG-results of non-carbonated areas and areas with various states of carbonation of the same sample material were calculated and evaluated. Concretes based on three different types of cement were produced and stored under accelerated carbonation conditions (1 % CO2 in air). The required sample material was obtained by cutting slices from various depth of previously CO2-treated specimen and subsequent grinding. During the sample preparation, a special attention was paid that no additional carbonation processes took place. As reference method for the determination of the carbonation depth the sprayed application of phenolphthalein solution was carried out. Microscopic analysis where examined to confirm the assumptions made previously. Furthermore, the observed effect of encapsulation of calcium hydroxide by carbonates caused by the accelerated carbonation conditions was examined more closely. KW - Microscopy KW - Accelerated carbonation KW - Carbonation behaviour KW - Concrete KW - Thermal Analysis PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-530571 DO - https://doi.org/10.1007/s10973-021-10966-1 VL - 147 IS - 11 SP - 1 EP - 14 PB - Springer AN - OPUS4-53057 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hüsken, Götz A1 - Pirskawetz, Stephan A1 - Hofmann, Detlef A1 - Basedau, Frank A1 - Gründer, Klaus-Peter A1 - Kadoke, Daniel T1 - The load-bearing behaviour of a reinforced concrete beam investigated by optical measuring techniques N2 - Bending beams and slabs are typical examples for structural elements used for reinforced concrete structures such as bridge girders, T-beams and bridge decks. Their strength related failure modes at maximum loading can be divided into bending and shear failure. The failure of beams loaded in bending can occur with or without indication. Therefore, conventional design concepts aim on failure modes with sufficient indication (e.g. large deflections or cracks), as it occurs in the case of secondary flexural compression failure. These indicating factors can also be used for Structural Health Monitoring (SHM) of civil infrastructure systems (e.g. bridges) to identify structural changes. In this context, non-destructive testing (NDT) methods offer different techniques for measuring deflections or crack formation and opening. However, profound knowledge on the determining failure modes of bending beams and their detection by NDT methods is required for the reliable application of SHM. Different NDT methods have been used in this study for analysing the load-bearing behaviour of a reinforced concrete beam in bending. The different measuring techniques are briefly described and their applicability is discussed by means of experimental results. For this purpose, the load-bearing behaviour of a reinforced concrete beam having a span of 2.75 m was investigated in a four-point bending flexural test at laboratory scale. The focus is on the characterization of determining failure modes by optical NDT and the comparison with classical measuring techniques (e.g. deformation measurements by displacement transducers). The bending beam was equipped with two single-mode (SM) sensor fibres. One fibre served as Distributed Optical Fibre Sensor (DOFS), whereas the other fibre contained Fibre Bragg Grating (FBG) sensors. In addition, optical deformation measurements using Digital Image Correlation (DIC) and Stereophotogrammetry (SP) were conducted. KW - Concrete beam KW - Bending KW - Digital image correlation KW - Stereophotogrammetry KW - Distributed fibre optic sensor KW - Fibre bragg grating PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-524762 DO - https://doi.org/10.1617/s11527-021-01699-6 VL - 54 IS - 3 SP - Article 102 PB - Springer AN - OPUS4-52476 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Weigel, Sandra A1 - Gehrke, M. A1 - Recknagel, Christoph A1 - Stephan, D. T1 - Identification and quantification of additives in bituminous binders based on FTIR spectroscopy and multivariate analysis methods N2 - Bitumen is a crucial building material in road construction, which is exposed to continuously higher stresses due to higher traffic loads and changing climatic conditions. Therefore, various additives are increasingly being added to the bitumen complicating the characterisation of the bituminous binder, especially concerning the reuse of reclaimed asphalt. Therefore, this work aimed to demonstrate that the combination of Fourier transform infrared (FTIR) spectroscopy with attenuated total reflexion (ATR) technique and multivariate evaluation is a very wellsuited method to reliable identify and quantify additives in bituminous binders. For this purpose, various unmodified and modified binders, directly and extracted from laboratory and reclaimed asphalts, were investigated with FTIR-ATR spectroscopy. The determined spectra, pre-processed by standard normal variate (SNV) transformation and the determination of the 1st derivation, were evaluated using factor Analysis (FA), linear discriminant analysis (LDA) and partial least square regression (PLSR). With this multivariate evaluation, first, a significant model with a very high hit rate of over 90% was developed allowing for the identification of styrene-butadiene copolymers (SBC), ethylene-copolymer bitumen (ECB) and different waxes (e.g. amide and Fischer-Tropsch wax) even if the additives do not show any additional peaks or the samples are multi-modified. Second, a quantification of the content is possible for SBC, ECB, and Amide wax with a mean error of RMSE B 0.4 wt% and a coefficient of determination of R2[90%. Based on these results, FTIR identification and quantification of additives in bituminous binders is a very promising method with a great potential. KW - Bituminous binders KW - FTIR-ATR KW - Multivariate evaluation KW - Identification and quantification of additives KW - Polymers KW - Waxes PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-534877 DO - https://doi.org/10.1617/s11527-021-01763-1 VL - 54 IS - 4 SP - 1 EP - 9 PB - Springer AN - OPUS4-53487 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Strangfeld, Christoph A1 - Schönsee, Eric A1 - Jeyifous, Olubunmi Anthony A1 - Izanlu, Morteza A1 - Hüsken, Götz ED - Rogge, Andreas ED - Meng, Birgit T1 - In situ Prozessüberwachung und Qualitätskontrolle bei der additiven Fertigung von Betonbauteilen N2 - In der additiven Fertigung von Beton wird kontinuierlich Material gemischt und verarbeitet. Dies erfordert eine kontinuierliche in situ Prozessüberwachung und Qualitätskontrolle. An der BAM wurde ein 3D-Betondrucker aufgebaut, der eine umfängliche Prozessüberwachung ermöglicht. Druck-, Temperatur- und Feuchtesensoren in der Pumpe und im Fördersystem erlauben ein kontinuierliches Monitoring des Frischbetons, während ein Laserlinienscanner am Druckkopf unmittelbar die gedruckte Ist-Kontur verfolgt. Die so gewonnenen Daten können Grundlage für die Erarbeitung von Normen für die additive Fertigung von Betonbauteilen sein und somit deren Standsicherheit gewährleisten. T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM Green Intelligent Building CY - Berlin, Germany DA - 16.10.2024 KW - In situ KW - Prozessüberwachung KW - Additive Fertigung KW - Betonbauteil PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-613064 SN - 978-3-9818564-7-7 SP - 138 EP - 146 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-61306 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rübner, Katrin ED - Rogge, Andreas ED - Meng, Birgit T1 - Vom Bauschutt zur leichten Gesteinskörnung N2 - Leichte Gesteinskörnungen können ressourcenschonend aus heterogenen und feinkörnigen Bau- und Abbruchabfällen in einem mehrstufigen Prozess durch thermische oder hydrothermale Stoffumwandlung hergestellt werden. Ihre Anwendung erfolgt in Leichtbetonen und Leichtmörteln, als Schüttung im Garten und Landschaftsbau oder auch als Filter- und Speichermaterial. In zahlreichen Forschungsprojekten wurden die Herstellungsprozesse entwickelt, die Materialeigenschaften optimiert und unterschiedliche Applikationen untersucht. In diesem Beitrag wird zusammenfassend über dieser Forschungsarbeiten berichtet. T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM Green Intelligent Building CY - Berlin, Germany DA - 16.10.2024 KW - Bauschutt KW - Gesteinskörnung PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-613105 SN - 978-3-9818564-7-7 SP - 70 EP - 77 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-61310 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Cook, Jake A1 - Tonon, Chiara A1 - Stohl, Leonie A1 - von Werder, Julia ED - Rogge, Andreas ED - Meng, Birgit T1 - Assessment of concrete bioreceptivity and model organism performance for use in algal biofilm green facade systems N2 - Elevated temperatures and high levels of air pollution in urban environments pose a significant threat to the health and life quality of inhabitants of these areas. This research aims to address these challenges by developing green façade systems using micro-algal biofilms. Both material and biological properties are assessed to optimise biofilm performance and durability. Cementitious samples with different pH levels and varying nutrient compositions are tested in combination with model microorganisms. Organism growth, health and adhesion are monitored over a 3-month period under controlled laboratory conditions. T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM Green Intelligent Building CY - Berlin, Germany DA - 16.10.2024 KW - Concrete bioreceptivity KW - Model organism performance KW - Algal biofilm KW - Algal biofilm green facade systems PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-613114 SN - 978-3-9818564-7-7 SP - 159 EP - 166 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-61311 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Robens-Radermacher, Annika A1 - Saif-Ur-Rehman, A1 - Wolf, Christoph A1 - Kujath, Cezary A1 - He, Yuxiang A1 - Mezhof, Alexander A1 - Hüsken, Götz A1 - Jeyifous, Olubunmi Anthony A1 - Unger, Jörg F. ED - Rogge, Andreas ED - Meng, Birgit T1 - Modellierung und Simulation von 3D Betondruck – Design- und Prozessoptimierung N2 - Der 3D Betondruck ermöglicht die effiziente und ressourcenschonendere Herstellung maßgeschneiderter Betonstrukturen. Trotz des großen Potentials gibt es bisher keine einheitlichen Normen und Standards für den sicheren und robusten 3D Betondruck. Der Beitrag zeigt das Potential numerischer Methoden und Modelle zur effizienten und ressourcenschonenden Design- und Prozessoptimierung des 3D Betondrucks. Dazu werden die aktuellen Forschungsarbeiten im Bereich der Entwicklung robuster und zuverlässiger numerischer Zwillinge, geeigneter Optimierungstools sowie digitaler Workflows diskutiert. T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM Green Intelligent Building CY - Berlin, Germany DA - 16.10.2024 KW - Modellierung KW - Simulation KW - 3D Betondruck KW - Designoptimierung KW - Prozessoptimierung PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-613023 SN - 978-3-9818564-7-7 SP - 132 EP - 137 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-61302 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Andrés Arcones, Daniel A1 - Unger, Jörg F. ED - Rogge, Andreas ED - Meng, Birgit T1 - Modell- und Parameterunsicherheiten am Beispiel eines digitalen Brückenzwillings N2 - Digitale Zwillinge bieten wertvolle Einblicke in das Verhalten von Bauwerken und ermöglichen eine fundierte Entscheidungsfindung. Durch den Einsatz von Simulationen, die auf physikalischen Gesetzen beruhen, ist es möglich, Vorhersagen über die Struktur auf der Grundlage zukünftiger oder hypothetischer Situationen zu treffen. Die Verwendung solcher Simulationen impliziert jedoch eine Reihe von Annahmen und Vereinfachungen, die unvermeidbare Fehler in die Vorhersagen einbringen. Die Quantifizierung dieser Unsicherheiten ist der Schlüssel für den Einsatz zuverlässiger digitaler Zwillinge von Brücken. T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM Green Intelligent Building CY - Berlin, Germany DA - 16.10.2024 KW - Modellunsicherheit KW - Parameterunsicherheit KW - Digitaler Brückenzwilling PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-613013 SN - 978-3-9818564-7-7 SP - 218 EP - 223 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-61301 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hüsken, Götz A1 - Jeyifous, Olubunmi Anthony A1 - Schönsee, Eric A1 - Strangfeld, Christoph ED - Rogge, Andreas ED - Meng, Birgit T1 - Beitrag zur Beurteilung der Wiederholbarkeit additiv gedruckter Betonbauteile N2 - Die additive Fertigung von Betonbauteilen, auch bekannt als 3D-Betondruck, ist eine Technologie, die im letzten Jahrzehnt aufgrund ihrer finanziellen und ökologischen Vorteile als nachhaltige Fertigungstechnologie viel Aufmerksamkeit erhalten hat. Obwohl die Vorteile der additiven Fertigung bereits durch zahlreiche Forschungs- und Demonstrationsprojekte gezeigt wurden, ist die Qualitätskontrolle während des Druckens äußerst anspruchsvoll und wird auch aufgrund fehlender harmonisierter Normen kaum angewendet. Aufgrund des kontinuierlichen Mischprozesses beim 3D-Betondruck ist es unmöglich Schwankungen des Trockenmörtels oder des Wassergehalts auszuschließen. Daher ist eine einzelne Stichprobe nicht mehr repräsentativ für das gesamte Bauteil und ein während des Druckens in einer Schicht auftretender Fehler kann die Integrität der gesamten Struktur beeinträchtigen. In diesem Beitrag werden die Ergebnisse eines als Fachwerkstruktur konzipierten Bogens, der unter vergleichbaren Randbedingungen mehrmals mit einem 3D-Betonextrusionsdrucker gedruckt wurde, vorgestellt. Jeder Bogen wurde auf seine mechanische Festigkeit und sein Tragverhalten geprüft. Die Ergebnisse der mechanischen Prüfungen der gedruckten Bögen werden mit Materialdaten aus klassischen Materialprüfungen verglichen und hinsichtlich ihrer statistischen Signifikanz diskutiert. T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM Green Intelligent Building CY - Berlin, Germany DA - 16.10.2024 KW - Additiv gedrucktes Betonbauteil KW - Beurteilung KW - Wiederholbarkeit PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-613043 SN - 978-3-9818564-7-7 SP - 126 EP - 131 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-61304 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Pirskawetz, Stephan A1 - Trattnig, H. A1 - Boehm, C. ED - Rogge, Andreas ED - Meng, Birgit T1 - Spanndrahtbrüche und ihr digitaler akustischer Zwilling N2 - Die Planung eines Monitorings von Spanndrahtbrüchen mit Schallemissionsanalyse erfordert viel Erfahrung und setzt eine akustische Analyse der Spannbetonstruktur voraus. Eine akustische Simulation der Struktur unterstützt die Optimierung der Sensoranordnung und erhöht die Zuverlässigkeit der Drahtbrucherkennung durch die Fusion von Simulations- und Messergebnissen in einer Datenbank. Künftig können Baulastträger und Monitoringanbieter von standardisierten – FAIR-en – akustischen Daten profitieren. T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM Green Intelligent Building CY - Berlin, Germany DA - 16.10.2024 KW - Spanndrahtbruch KW - Digitaler akustischer Zwilling PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-613038 SN - 978-3-9818564-7-7 SP - 224 EP - 229 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-61303 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Stohl, Leonie A1 - Cook, Jake A1 - von Werder, Julia ED - Rogge, Andreas ED - Meng, Birgit T1 - Bioreceptive concrete surfaces: Understanding material-biology interactions for façade greening N2 - The climate crisis has led to a growing demand for environmentally oriented approaches in the construction industry, including not only eco-friendly materials, but also the greening of urban spaces. Microbial facade greening with algae is a novel concept based on the inherent bioreceptive properties of different building materials. This study focuses on the influence of physical material properties on biofilm formation. Differently textured samples from the same UHPC mix were produced and their roughness and water absorption documented. The samples were then weathered under laboratory conditions to observe material-algae interactions. T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM Green Intelligent Building CY - Berlin, Germany DA - 16.10.2024 KW - Bioreceptive KW - Material-biology Interaction KW - Façade greening PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-613096 SN - 978-3-9818564-7-7 SP - 153 EP - 158 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-61309 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Weise, Frank A1 - Kühnel, Alena A1 - Fladt, Matthias A1 - Stelzner, Ludwig ED - Rogge, Andreas ED - Meng, Birgit T1 - Dauerhaftigkeit von Betonfahrbahndecken im deutschen Bundesautobahnnetz N2 - Die Dauerhaftigkeit der Betondecke und deren Oberflächentexturierung bestimmen maßgebend das Ge-brauchsverhalten von Betonfahrbahnen. Der Beitrag zeigt die Leistungsfähigkeit der Innenhydrophobierung als neuartige AKR-Vermeidungsstrategie zur Sicherstellung der geplanten, normativen Nutzungsdauer, auch unter Verwendung grenzwertig alkaliempfindlicher Gesteinskörnungen, auf. Zusätzlich wird eine neuartige Prüfmethodik zur in situ Verfolgung der 3D-Texturveränderungen auf einem erneuerten BAB-Abschnitt mit Grindingtextur vorgestellt. Diese beeinflussen maßgebend die Griffigkeit und die Reifen-Fahrbahn-Geräusche. T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM Green Intelligent Building CY - Berlin, Germany DA - 16.10.2024 KW - Betonfahrbahnen KW - Alkali-Kieselsäure-Reaktion KW - Innenhydrophobierung PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-613184 SN - 978-3-9818564-7-7 SP - 232 EP - 243 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-61318 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Recknagel, Christoph A1 - Weigel, Sandra A1 - Hoppe, Johannes ED - Rogge, Andreas ED - Meng, Birgit T1 - Dauerhafte Funktionsfähigkeit von Bauwerksfugen - Das performance concept in der Abdichtungstechnik von Betonfahrbahnen N2 - Verlässliche Funktionsfähigkeit und planbare Lebensdauerzyklen sind entscheidend für die Weiterentwicklung der Betonbauweise im Straßenbau. Aus Forschungsergebnissen zur Fugenproblematik in hochbeanspruchten Betonfahrbahnen unter Diskussion regelungsspezifischer Erfordernisse erfolgt ein Plädoyer für eine funktionsanalytische Untersuchung von Fugensystemen. Mit aktuellen Projekten werden die Datengrundlage zu maßgebenden Einwirkungen und eine innovative versuchstechnische Infrastruktur als methodische Voraussetzungen zur Erhöhung zuverlässiger Funktionsfähigkeit von Bauwerksfugen bereitgestellt. T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM Green Intelligent Building CY - Berlin, Germany DA - 16.10.2024 KW - Betonfahrbahnen KW - Bauwerksfugen KW - Abdichtungstechnik von Betonfahrbahnen KW - SensoJointField KW - INFUKON PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-613207 SN - 978-3-9818564-7-7 SP - 244 EP - 252 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-61320 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Weigel, Sandra A1 - Recknagel, Christoph ED - Rogge, Andreas ED - Meng, Birgit T1 - Ein Ausblick: Alternative Bindemittel für bitumenhaltige Materialien N2 - Im Straßen- und Ingenieurbau sind neben dem Baustoff Beton auch bitumenhaltige Materialien in Flächenab-dichtungen, Dehnfugenkonstruktionen und Asphaltbelägen von entscheidender Bedeutung. Die bestehende Erdölabhängigkeit dieser Materialien fordert jedoch ein dringendes Umdenken, wobei langfristig die Substitu-tion des Bitumens durch nachhaltige, biobasierte Alternativmaterialien angestrebt werden sollte. Durch eine partielle Substitution wäre zudem bereits kurz- bis mittelfristig eine Reduzierung der Erdölabhängigkeit mög-lich, wobei sich z.B. Rückstände der Mikroalgenaufbereitung oder Lignin als Substitutionsprodukte eignen. T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM Green Intelligent Building CY - Berlin, Germany DA - 16.10.2024 KW - Alternative KW - Bindemittel KW - Bitumenhaltige Materialien PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-613138 SN - 978-3-9818564-7-7 SP - 167 EP - 174 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-61313 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Pittrich, Tim A1 - Stelzner, Ludwig A1 - Weise, Frank ED - Rogge, Andreas ED - Meng, Birgit T1 - Tunnelbrand – Abplatzverhalten von normalfesten Betonen mit verschiedenen klinkereffizienten Zementen N2 - Zur Verminderung der CO2-Emissionen der Bauindustrie gewinnen klinkereffiziente Zemente immer mehr an Bedeutung und werden vermehrt in Ingenieurbauwerken eingesetzt. Das brandinduzierte Abplatzverhalten von Betonen mit diesen Zementen ist allerdings nur bedingt bekannt und ist u.a. im Tunnelbau von hoher Bedeutung. Im Zuge dessen, wurden normalfeste Betone mit vier verschiedenen Zementen (CEM I, CEM II/A-LL, CEM III/A und CEM II/B-Q) auf ihr brandinduziertes Abplatzverhalten untersucht. Die Ergebnisse zeigen, dass Betone mit klinkereffizienten Zementen zu stärkeren Abplatzungen neigen. T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM Green Intelligent Building CY - Berlin, Germany DA - 16.10.2024 KW - Verminderung CO2-Emissionen KW - Brandinduziertes Abplatzverhalten KW - Klinkereffiziente Zemente PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-613215 SN - 978-3-9818564-7-7 SP - 253 EP - 262 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-61321 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bednarska, Dalia A1 - von Werder, Julia ED - Rogge, Andreas ED - Meng, Birgit T1 - Modification of clay-based materials with a novel geopolymer: potential application towards water-resistance N2 - Earth is probably the most eco-friendly building material. However, since earthen materials dissolve in water easily their application is limited. The presented manuscript aims to verify the usefulness of a one-part geo- polymer developed at BAM as a stabilizing agent for earthen mortars. The experimental study encompasses water-resistance, compressive strength, linear shrinkage, water vapour permeability and microstructural anal- ysis of the reference and the modified earthen plaster. The presented results show that the modification visibly affects the properties of the initial material providing its water-resistance. T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM Green Intelligent Building CY - Berlin, Germany DA - 16.10.2024 KW - Clay-based materials KW - Water-resistance KW - Novel geopolymer PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-613150 SN - 978-3-9818564-7-7 SP - 94 EP - 101 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-61315 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hille, Falk A1 - Herrmann, Ralf A1 - Schneider, Ronald A1 - Pitters, S. A1 - Wedel, F. A1 - Hindersmann, I. T1 - Developing a guideline for structural health monitoring of road bridges in Germany N2 - In recent years, Structural Health Monitoring (SHM) has become a useful and increasingly widely used tool for supporting lifetime extensions of existing bridges with known structural deficiencies or indications of potentially critical damages or damage processes. At the same time, methods and tools are emerging, which enable monitoring-informed predictive maintenance of new and existing bridges based on digital twins. The monitoring process – starting from the definition of monitoring actions and ending with decisions based on monitoring outcomes – is complex and requires expertise in structural engineering, operation and maintenance of bridges, metrology, and data analytics. To support German road authorities, engineering consultancies, building contractors and other stakeholders of the bridge management, the Federal Highway Research Institute (BASt) has initiated the development of a new guideline for applying SHM as part of the management of road bridges. The guideline will present various use cases and for each identified use case, it will propose a proven monitoring scheme. In addition, the guideline will provide guidance on assessing the benefits of SHM as well as a common approach to managing monitoring data as a systematic basis for integrating monitoring data in the bridge management. This contribution discusses the motivation, objectives, and scope of the guideline, describes its use case centric structure and outlines the proposed data management. T2 - IABMAS 2024 CY - Kopenhagen, Danmark DA - 24.06.2024 KW - Guideline KW - Structural health monitoring KW - Road bridges KW - Infrastructure PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-613947 SN - 978-1-032-77040-6 DO - https://doi.org/10.1201/9781003483755-236 SP - 2009 EP - 2017 PB - CRC Press AN - OPUS4-61394 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Neugum, Tim A1 - Stelzner, Ludwig A1 - Häßler, Dustin A1 - Hothan, Sascha A1 - Zehfuß, J. ED - Rogge, Andreas ED - Meng, Birgit T1 - Feuerwiderstand gezwängter Stahlbetonstützen N2 - Bei realen Brandereignissen stellen sich in der Regel mechanische und thermische Randbedingungen ein, die deutlich von denen in präskriptiven, bauteilorientierten Brandprüfungen abweichen. Beispielsweise werden Interaktionen der brandbeanspruchten Bauteile mit dem umgebenden Tragwerk und daraus resultierende Zwangsbeanspruchungen bei konventionellen Brandprüfungen nicht berücksichtigt. Mit Hilfe der Substrukturtechnik kann das Verhalten einer Stütze im Brandfall unter Berücksichtigung der Interaktion mit dem umgebenden Tragwerk untersucht werden. T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM Green Intelligent Building CY - Berlin, Germany DA - 16.10.2024 KW - Brandprüfungen KW - Substrukturtechnik KW - Zwangsbeanspruchungen KW - Brandbeanspruchung PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-613249 SN - 978-3-9818564-7-7 SP - 270 EP - 277 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-61324 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Thiele, Marc A1 - Herrmann, Ralf A1 - Degener, Sebastian A1 - Pirskawetz, Stephan A1 - Loewe, Anna ED - Rogge, Andreas ED - Meng, Birgit T1 - Monitoring an Türmen von Onshore Windenergieanlagen in Betonbauweise im Hinblick auf Ermüdung N2 - Der Beitrag stellt das Messkonzept sowie dessen Umsetzung für ein umfassendes Monitoringsystem an einer onshore Windenergieanlage mit einem Hybridturm vor. Dieses ist Bestandteil des Forschungsvorhabens Win-ConFat – Structure, welches neben der Validierung geeigneter Sensorik auch die Bewertung des Zustands und der möglichen Restlebensdauer der ermüdungsbeanspruchten Betonstruktur zum Ziel hat. Neben dem Monitoringsystem werden erste Messergebnisse aus den Betriebsdaten sowie vom Verhalten der Turmstruktur vorgestellt. T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM Green Intelligent Building CY - Berlin, Germany DA - 16.10.2024 KW - Monitoring KW - Windenergieanlage und Hybridturm KW - Ermüdung KW - WinConFat – Structure PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-613276 SN - 978-3-9818564-7-7 SP - 286 EP - 293 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-61327 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hering, Marcus A1 - Fiedler, Georg A1 - Schubert, T. A1 - Hille, Falk A1 - Hüsken, Götz A1 - Beckmann, B. ED - Rogge, Andreas ED - Meng, Birgit T1 - Großmaßstäbliche Impaktversuche mit Stahlbetonplatten – Konzeptionierung und Vorbereitung N2 - Seit 1977 ist der Flugzeugabsturz ein wesentliches Belastungsszenario bei der Auslegung von Kernkraftwerken. Zur Untersuchung dieses Szenarios wurden umfassende Studien durchgeführt, welche die Reaktion von Stahlbetonkonstruktionen unter Stoßbelastung analysieren. Da großmaßstäbliche Experimente teuer und aufwendig sind, gewinnen skalierte Versuche zunehmend an Bedeutung. Im Rahmen eines Forschungsprojekts der TU Dresden und der BAM wurden Grundlagen für skalierte Impaktversuche im großen Maßstab geschaffen, um die Übertragbarkeit vom Labor- auf Realmaßstab zu ermöglichen. T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM Green Intelligent Building CY - Berlin, Germany DA - 16.10.2024 KW - Fallturm KW - Impakt KW - Stahlbetonbauteile PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-613257 SN - 978-3-9818564-7-7 SP - 278 EP - 285 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-61325 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Deresse, N. E. A1 - Thiele, Marc A1 - Pirskawetz, Stephan A1 - Sarem, M. A1 - Francois, St. A1 - Verstrynge, E. T1 - Evaluation of Concrete Fatigue Damage with Elastic Wave-based Measurement Techniques N2 - The fatigue damage evolution and the fatigue life of quasi-brittle materials such as concrete are not yet completely understood. Accordingly to get better insights, researchers have recently been incorporating advanced measuring techniques in their fatigue experiments. In this research, acoustic emission techniques (AET), active ultrasonic, and deformation measurements are used to track the damage evolution of concrete samples subjected to fatigue loading. The samples are subjected to constant amplitude and stepwise fatigue loading in Brazilian splitting test set-ups. Initially, a good agreement is observed between the deformation and the ultrasonic measurements in capturing the crack propagation during Brazilian splitting tests. The three fatigue damage phases could be identified with all of the three techniques. The Phase II damage rates quantified by deformation measurements and AET in stepwise fatigue tests were used to predict the number of cycles to failure at various stress levels. The predictions were validated using the number of cycles to failure of the constant amplitude fatigue tests. T2 - 36th Conference of the European Working Group on Acoustic Emission CY - Potsdam, Germany DA - 18.09.2024 KW - Concrete KW - Acoustic emission KW - Ultrasonic testing KW - Fatigue PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-615677 DO - https://doi.org/10.58286/30228 SN - 1435-4934 VL - 29 IS - 10 SP - 1 EP - 10 PB - NDT.net AN - OPUS4-61567 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Stelzner, Ludwig A1 - Eiz Eddin, Ahmad A1 - Häßler, Dustin A1 - Hothan, Sascha ED - Rogge, Andreas ED - Meng, Birgit T1 - Zum Feuerwiderstand von filigranen Deckenelementen aus vorgespanntem Carbonbeton N2 - Der Einsatz von hoch zugbeanspruchbarem und korrosionsbeständigem Carbongelege anstelle herkömmlichen Spannstahls ermöglicht es Beton vorzuspannen und gleichzeitig die Betondeckung auf ein für den Verbund nötiges Minimum zu reduzieren. Der Wechsel von massiven zu filigranen Bauteilen führt in der Regel aufgrund der geringeren thermischen Masse zu einer Abnahme des Feuerwiderstandes. Der Beitrag stellt Versuchsergebnisse zum Abplatzverhalten von Carbonbeton vor, die im Rahmen des Verbundvorhabens „Vorgespannte Carbonbetondecken mit reduzierten Querschnitten“ (CaPreFloor) erzielt wurden. T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM Green Intelligent Building CY - Berlin, Germany DA - 16.10.2024 KW - Feuerwiderstand KW - Carbonbeton KW - Abplatzverhalten KW - CaPreFloor PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-613221 SN - 978-3-9818564-7-7 SP - 263 EP - 269 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-61322 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Krüger, Miriam E. A1 - Hilbig, Harald A1 - Stelzner, Ludwig A1 - Machner, Alisa T1 - Effect of the chemical composition of synthetic alkali-silica gels on their structure, swelling behavior and water uptake N2 - For alkali-silica reaction (ASR) gels, the relationship between swelling expansion, structure and chemical composition, particularly the effect of aluminum, remains unknown. This study investigates the structure, swelling expansion and associated water uptake of synthetic ASR gels with various Al/Si (0–0.1) and Ca/Si (0.1–0.4) ratios. The results show that aluminum incorporated into the gel structure reduces the overall swelling expansion and the leaching of silicate species during the swelling test. Moreover, they revealed that water in the Al-ASR gels is more tightly bound, reducing the overall water uptake compared to the Al-free ASR gels. Additionally, there is a linear correlation between the maximal swelling results and the ASR gel composition. However, no direct correlation emerged between the amount of water uptake and the free swelling of the ASR gels, which indicates that other factors, like the type of water bonding and pore size of the gels, are decisive for the swelling mechanism. KW - Concrete KW - Alkali-silica reaction (ASR) KW - Durability KW - 1H NMR relaxometry KW - 29Si NMR KW - 27Al NMR KW - FTIR KW - Al-ASR gel KW - Swelling test PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-624268 DO - https://doi.org/10.1016/j.cemconres.2024.107596 VL - 184 SP - 1 EP - 18 PB - Elsevier B.V. AN - OPUS4-62426 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Fürst, Richard A1 - Häßler, Dustin A1 - Stelzner, Ludwig A1 - Hothan, Sascha T1 - Fire resistance of existing steel structures with aged intumescent coating based on an in situ test method N2 - Intumescent coatings are commonly used in civil engineering to increase the fire resistance of steel structures. Exposed to fire, the intumescent coating reacts and forms a thermal protective char around the steel member. Thus, the heating of the steel is significantly slowed down and the fire resistance can be improved. Information regarding the scope of application and the durability of intumescent coatings are given in national approvals or European Technical Assessment documents. Due to the environmental conditions, intumescent coatings are subjected to ageing effects, which can reduce the durability and their thermal protection performance. To predict the durability for several years, during the approval procedure the behaviour of intumescent coatings is predominantly extrapolated based on accelerated artificial ageing. The established German and European assessment procedures to test and assess durability assume a working life of at least 10 years. Additional evidence may be required for longer periods. However, at present there is no method of verifying the thermal performance of existing structural members on site. For this reason, BAM is conducting the research project "INSIST" [1] to develop a minimally invasive in situ test method to determine the fire resistance of existing steel structures with applied intumescent coating. The investigation includes the development of a mobile prototype furnace. The paper describes the test setup, the developed prototype furnace, and the results of the performed test programme on uncoated and coated steel specimens. Based on this, recommendations for the test procedure are given. KW - In situ testing KW - Fire resistance KW - Intumescent coating KW - Steel KW - Thermal protection KW - Durability PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-629533 DO - https://doi.org/10.1016/j.firesaf.2025.104380 VL - 153 SP - 1 EP - 12 PB - Elsevier Ltd. AN - OPUS4-62953 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Ferrier, Emmanuel A1 - Michel, Laurent A1 - Thiele, Marc A1 - Mercier, Julien T1 - Strain-rate effect on the bond strength of external bonded reinforced carbon fiber-reinforced polymer for concrete structure N2 - The aim of the presented study is to investigate the dynamic loading strength of an external bonded fiber-reinforced polymers (FRP) system under seismic loading. 16 bonded FRP samples under different loading speeds ranging as 0.0000167–0.8 m /s were examined to determine the characteristics of the FRP bond strength on the concrete. The mechanical tests involved measuring the concrete/FRP shear properties using a double-lap shear test. Sixteen concrete specimens were cast, strengthened and surface preparation, instrumented, and driven to failure in the LMC laboratory and the BAM laboratory (Germany). Dynamic loading increased the bonded strength mainly because of an increase in the concrete tensile strength. Experimental data are then analysed and competed with the equation given by the new European standard that develop the design of external bonded FRP. The characteristic properties and bonded strength obtained by design equation were compared. Based on the results design equation are modified. KW - EBR strengthening system KW - Desing bond strength KW - Durability PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-625354 DO - https://doi.org/10.1016/j.conbuildmat.2025.140216 SN - 1879-0526 VL - 466 SP - 1 EP - 14 PB - Elsevier Ltd. AN - OPUS4-62535 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Andrés Arcones, Daniel A1 - Weise, M. A1 - Koutsourelakis, P-S. A1 - Unger, Jörg F. T1 - Bias Identification Approaches for Model Updating of Simulation-based Digital Twins of Bridges N2 - Simulation-based digital twins of bridges have the potential not only to serve as monitoring devices of the current state of the structure but also to generate new knowledge through physical predictions that allow for better-informed decision-making. For an accurate representation of the bridge, the underlying models must be tuned to reproduce the real system. Nevertheless, the necessary assumptions and simplifications in these models irremediably introduce discrepancies between measurements and model response. We will show that quantifying the extent of the uncertainties introduced through the models that lead to such discrepancies provides a better understanding of the real system, enhances the model updating process, and creates more robust and trustworthy digital twins. The inclusion of an explicit bias term will be applied to a representative demonstrator case based on the thermal response of the Nibelungenbrücke of Worms. The findings from this work are englobed in the initiative SPP 100+, whose main aim is the extension of the service life of structures, especially through the implementation of digital twins. T2 - EWSHM 2024 11th European Workshop on Structural Health Monitoring CY - Potsdam, Germany DA - 10.06.2024 KW - Digital Twins KW - Model Bias KW - SPP100+ KW - Bridge Monitoring PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-622522 DO - https://doi.org/10.58286/30524 SN - 2941-4989 IS - 12 SP - 1 EP - 10 PB - NDT.net GmbH & Co. KG CY - Mayen, Germany AN - OPUS4-62252 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Pirskawetz, Stephan A1 - Zaripova, Gulshat A1 - Brinkmann, Nienke A1 - Gebraad, Lars A1 - Boehm, Christian A1 - Trattnig, Horst T1 - Simulation der Schallemissionen von Spanndrahtbrüchen N2 - In den 1950er Jahren setzte sich die Spannbetonbauweise für Brücken mit größeren Spannweiten durch. Heute existieren im deutschen Bundesfernstraßennetz ca. 21.000 Spannbetonbrücken. Die mangelnde Erfahrung in der Anfangszeit dieser Bauweise stellt uns heute vor Probleme hinsichtlich einer Kombination aus Korrosion und Ermüdung der Spannglieder. Hauptursachen sind Spannungsrisskorrosion, deutlich gewachsene Verkehrslasten sowie ungenügende Annahmen zu Temperaturlasten. Insbesondere Spanndrahtbrüche infolge Spannungsrisskorrosion können zu einem Strukturversagen ohne Ankündigung führen. Spannstähle mit einer starken Gefährdung für Spannungsrisskorrosion wurden in der Bundesrepublik bis 1965, in der ehemaligen DDR bis Ende der 1980er Jahre verbaut. Um katastrophale Schadensfälle zu verhindern, müssen Bauwerke unter Verdacht auf Spannungsrisskorrosion in Kombination mit unzureichendem Ankündigungsverhalten überwacht werden. Derzeit ist die Schallemissionsanalyse die einzige zuverlässige und ökonomisch vertretbare Überwachungsmethode. Damit kann der sichere Betrieb der Bauwerke über die verbleibende Nutzungsdauer gewährleistet werden. Die DGZfP-Richtlinie SE05 “Detektion von Spanndrahtbrüchen mit Schallemissionsanalyse” beschreibt detailliert Planung, Installation und Betrieb solcher Monitoringsysteme. Im Projekt SimAS “Digitaler Zwilling zur Simulation der Ausbreitung akustischer Wellen in Spannbetonelementen” werden die Grundlagen für eine Optimierung der Monitoringsysteme auf Basis der Schallemissionsanalyse gelegt. Eine akustische Simulation der Struktur und deren Fusion mit Messdaten unterstützt sowohl die vorbereitenden akustischen Analysen der Brücken als auch die Planung der Monitoringsysteme und die Drahtbrucherkennung T2 - SCHALL 25 – Schallemissionsanalyse und Zustandsüberwachung mit geführten Wellen CY - Dresden, Germany DA - 27.03.2025 KW - Acoustic Emission KW - Simulation KW - Schallemission KW - Spannbetonbrücke KW - Spanndrahtbruch KW - Digitaler akustischer Zwilling KW - Spannungsrisskorrosion KW - Schallemissionsanalyse KW - Schallausbreitung PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-628347 DO - https://doi.org/10.58286/30964 VL - 4 SP - 1 EP - 6 PB - Deutsche Gesellschaft für Zerstörungsfreie Prüfung AN - OPUS4-62834 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Unger, Jörg F. T1 - From advanced simulation models to industrial applications N2 - The integration of advanced simulation models into industrial applications, especially in civil engineering, is a challenge that requires to develop new concepts. In particular, this is related to the validation of models using open access and FAIR data as well as objective methods for identifying model parameters and model comparison with the integration of both the models and their calibration into reproducible workflow systems. The challenges are illustratively discussed for a variety of applications ranging from bridge monitoring over the structural behavior under blast loading up to the additive manufacturing of concrete. An important basis for model validation is the existence of machine-readable data structures for experimental data, e.g. based on semantic representations. In addition, platforms to share this structured data in a searchable format in addition with reproducible scientific workflows must be established. Based on these tools, objective methods for model parameter estimation and validation of the models are a critical step in ensuring their accuracy and usefulness in industrial applications. Bayesian inference is one approach that can be used to optimize simulation parameters, improving the accuracy of the model while being able to estimate the uncertainty. Integrating these procedures in a real-time application with a bidirectional information exchange between the physical systems and the virtual simulation model leads to the concept of digital twins. For complex simulation models, the computational efficiency is a significant barrier both for real-time applications and in the context of model calibration with potentially millions of required forward-model evaluations. As a consequence, reduced order modeling approaches such as the proper generalized decomposition method can be used to build an efficient to evaluate model - speeding up the online computation but requiring a precomputation in an offline phase. Finally, a perspective for integrating material and structural design into a joint design optimization is given. The integration of advanced simulation models into industrial applications is a rapidly evolving field with significant potential for innovation and progress. From additive manufacturing of concrete to digital twins and reduced order modeling, there are many tools and approaches that can be used to improve industrial processes and drive progress in a variety of industries. T2 - Kolloquium des MUSEN-Zentrums Braunschweig CY - Braunschweig, Germany DA - 04.05.2023 KW - Digital twins KW - Reduced order models PY - 2023 AN - OPUS4-60842 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Frei, Vivian A1 - Pirskawetz, Stephan A1 - Thiele, Marc A1 - Rogge, Andreas T1 - Ermüdungsverhalten von Beton für unterschiedliche Probekörpergeometrien N2 - Die heute in der Anwendung befindlichen Bemessungskonzepte für Ermüdung von Beton stammen zum Teil noch aus den 1990er Jahren und sind speziell hinsichtlich hochfester Betone konservativ ausgelegt. Um die Vorteile von Türmen für Windkraftanlagen, vor allem auch aus hochfesten Betonen, im Zuge des geplanten Ausbaus der Windenergieversorgung in Deutschland wirtschaftlich nutzbar zu machen, müssen diese Bemessungskonzepte weiterentwickelt werden. Dafür sind umfangreiche Untersuchungen zur Ermittlung von Bruchlastwechselzahlen und zur Charakterisierung der Schädigungsentwicklung unter Ermüdungsbeanspruchung erforderlich. Allgemein anerkannte bzw. verbindliche Regelwerke oder Verfahren zur experimentellen Bestimmung der Ermüdungsfestigkeit (Bruchlastwechselzahlen) an Betonproben gibt es zurzeit aber nicht und die bisher durchgeführten Untersuchungen variieren in Parametern wie Probengeometrie, Probengröße und Prüffrequenz. Eine vergleichende Analyse der Ergebnisse der Studien und insbesondere die Übertragbarkeit auf bauteilrelevante Abmessungen ist auf dieser Grundlage nur sehr eingeschränkt möglich. KW - Ermüdungsverhalten KW - Probekörpergeometrien KW - Druckschwellenversuch KW - Bruchlastwechselzahlen KW - Beton PY - 2023 UR - https://www.betonverein.de/dbv-heft-52-materialermuedung-von-stahl-und-spannbeton-unter-hochzyklischer-beanspruchung-ergebnisse-des-verbundforschungsvorhabens-win-con-fat IS - 52 SP - 19 EP - 22 PB - Deutscher Beton- und Bautechnik-Verein E.V. CY - Berlin AN - OPUS4-58746 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Robens-Radermacher, Annika A1 - Unger, Jörg F. T1 - Efficient structural reliability analysis by using a PGD model in an adaptive importance sampling schema N2 - One of the most important goals in civil engineering is to guarantee the safety of the construction. Standards prescribe a required failure probability in the order of 10−4 to 10−6. Generally, it is not possible to compute the failure probability analytically. Therefore, many approximation methods have been developed to estimate the failure probability. Nevertheless, these methods still require a large number of evaluations of the investigated structure, usually finite element (FE) simulations, making full probabilistic design studies not feasible for relevant applications. The aim of this paper is to increase the efficiency of structural reliability analysis by means of reduced order models. The developed method paves the way for using full probabilistic approaches in industrial applications. In the proposed PGD reliability analysis, the solution of the structural computation is directly obtained from evaluating the PGD solution for a specific parameter set without computing a full FE simulation. Additionally, an adaptive importance sampling scheme is used to minimize the total number of required samples. The accuracy of the failure probability depends on the accuracy of the PGD model (mainly influenced on mesh discretization and mode truncation) as well as the number of samples in the sampling algorithm. Therefore, a general iterative PGD reliability procedure is developed to automatically verify the accuracy of the computed failure probability. It is based on a goal-oriented refinement of the PGD model around the adaptively approximated design point. The methodology is applied and evaluated for 1D and 2D examples. The computational savings compared to the method based on a FE model is shown and the influence of the accuracy of the PGD model on the failure probability is studied. KW - Reliability KW - Probability of failure KW - Adaptive importance sampling KW - Reduced order models KW - Proper Generalized Decomposition PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-510345 DO - https://doi.org/10.1186/s40323-020-00168-z VL - 7 SP - Article number: 29 PB - SpringerOpen AN - OPUS4-51034 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - INPR A1 - Villani, P. A1 - Unger, Jörg F. A1 - Weiser, M. T1 - Adaptive Gaussian process regression for Bayesian inverse problems N2 - We introduce a novel adaptive Gaussian Process Regression (GPR) methodology for efficient construction of surrogate models for Bayesian inverse problems with expensive forward model evaluations. An adaptive design strategy focuses on optimizing both the positioning and simulation accuracy of training data in order to reduce the computational cost of simulating training data without compromising the fidelity of the posterior distributions of parameters. The method interleaves a goal-oriented active learning algorithm selecting evaluation points and tolerances based on the expected impact on the Kullback-Leibler divergence of surrogated and true posterior with a Markov Chain Monte Carlo sampling of the posterior. The performance benefit of the adaptive approach is demonstrated for two simple test problems. T2 - Algoritmy 2024 - Central-European Conference on Scientific Computing CY - Vysoké Tatry, Slovakia DA - 15.03.2024 KW - Active learning KW - Bayesian inverse problems KW - Gaussian Process Regression (GPR) KW - Parameter identification KW - Surrogate models PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-600408 DO - https://doi.org/10.48550/arXiv.2404.19459 SN - 2331-8422 SP - 1 EP - 12 PB - Cornell University CY - Ithaca, NY AN - OPUS4-60040 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schönsee, Eric A1 - Jeyifous, Olubunmi Anthony A1 - Strangfeld, Christoph A1 - Hüsken, Götz T1 - Investigations on multi-sensor data for monitoring volume flow during the printing process N2 - Extrusion based 3D concrete printing (3DCP) is a growing technology because of its high potential for automating construction and the new possibilities of design. In conventional construction methods, a sample is taken to be representative for one material batch. However, in 3DCP continuous mixing is used which results in variations during the mixing process. Therefore, one sample is not representative for the entire structure. This leads to the necessity of continuous and real-time process monitoring. This study focuses on the variations of pressure and temperature which are caused by changes in the material due to the ongoing mixing process. Changes in material, which is transported downstream, are influencing sensor signals in different positions with a time delay. In the following, the data is analysed to investigate if the changing material and the so caused change in pressure can be used to calculate volume flow. T2 - Digital Concrete 2024 CY - Munich, Germany DA - 04.09.2024 KW - Additive manufacturing KW - In-line Monitoring KW - Volume Flow KW - Process Control PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:gbv:084-2024081513042 DO - https://doi.org/10.24355/dbbs.084-202408151304-0 SP - 1 EP - 3 AN - OPUS4-61001 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - von Werder, Julia A1 - Simon, Sebastian A1 - Gardei, André A1 - Fontana, P. A1 - Meng, Birgit T1 - Thermal and hydrothermal treatment of UHPC: influence of the process parameters on the phase composition of ultra-high performance concrete N2 - Several studies show that thermal and hydrothermal treatment can further improve the excellent properties of UHPC in terms of mechanical strength and durability. While for the thermal treatment the increase in strength is attributed to an intensified pozzolanic and hydraulic reaction, for the hydrothermal treatment previous studies accredited it mostly to the formation of tobermorite. In the presented study thermal and hydrothermal treatment of UHPC samples was systematically varied and the phase formation analysed related to the strength development of a reference sample cured for 28 days in water. For the thermal treatment the results show that the strength increase depends on the protection against desiccation and can be ascribed to an improved pozzolanic reaction of the siliceous fillers. To achieve a significant enhancement of strength, a pre-storage time of few days and a long dwell time at elevated temperature/pressure are required. For the hydrothermal treatment already heating the specimens up to 185 °C in saturated steam followed by an immediate cooling leads to a substantial increase in compressive strength. Pre-storage time did not affect the result as far as a minimum of several hours is guaranteed. The improved performance is due to an increase in the pozzolanic and hydraulic reaction. Surprisingly, tobermorite was only found within a very thin layer at the surface of the sample, but not in the bulk. Sulphate and aluminium stemming from the decomposition of the ettringite are bound in the newly formed phases hydroxylellestadite and hydrogarnet. KW - UHPC KW - Thermal treatment KW - Hydrothermal treatment KW - Compressive strength KW - Phase development KW - Durability KW - Tobermorite KW - Hydroxylellestadite KW - Hydrogarnet PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-523402 DO - https://doi.org/10.1617/s11527-021-01633-w SN - 1871-6873 SN - 1359-5997 VL - 54 IS - 1 SP - Article 44 PB - Springer Nature AN - OPUS4-52340 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Viefhues, Eva A1 - Döhler, M. A1 - Hille, Falk A1 - Mevel, L. T1 - Fault detection for linear parameter varying systems under changes in the process noise covariance N2 - Detecting changes in the eigenstructure of linear systems is a comprehensively investigated subject. In particular, change detection methods based on hypothesis testing using Gaussian residuals have been developed previously. In such residuals, a reference model is confronted to data from the current system. In this paper, linear output-only systems depending on a varying external physical parameter are considered. These systems are driven by process noise, whose covariance may also vary between measurements. To deal with the varying parameter, an interpolation approach is pursued, where a limited number of reference models – each estimated from data measured in a reference state – are interpolated to approximate an adequate reference model for the current parameter. The problem becomes more complex when the different points of interpolation correspond to different noise conditions. Then conflicts may arise between the detection of changes in the eigenstructure due to a fault and the detection of changes due to different noise conditions. For this case, a new change detection approach is developed based on the interpolation of the eigenstructure at the reference points. The resulting approach is capable of change detection when both the external physical parameter and the process noise conditions are varying. This approach is validated on a numerical simulation of a mechanical system. T2 - 21st IFAC World Congress CY - Online meeting DA - 13.07.2020 KW - Linear parameter varying systems KW - Fault detectionchanging KW - Process noise KW - Subspace-based residual KW - Model interpolation PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-524652 DO - https://doi.org/10.1016/j.ifacol.2020.12.868 SN - 2405-8963 VL - 53 IS - 2 SP - 13668 EP - 13673 PB - Elsevier AN - OPUS4-52465 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wallau, Wilma A1 - Recknagel, Christoph T1 - Durability Assessment of Structural Sealant Glazing Systems applying a Performance Test Method N2 - During the service life of a Structural Sealant Glazing (SSG) facade, its silicone bond is exposed to climatic, chemical, and mechanical loads. While current durability assessment methods schedule separate test programmes for accelerated weathering and fatigue, the presented test applies mechanical loading and weather cycling simultaneously to simulate 50 years of use. Specifically designed medium-scale system specimens resemble a common SSG-bond. Displacement-controlled sinusoidal load cycles in two load directions subject these specimens to tensile, compression and shear loads. Weathering comprises temperature and humidity cycles, UV-radiation, and application of water and detergent. During testing, the forces transmitted by the system specimens are continuously measured for performance assessment. The resulting system response reveals mechanical performance characteristics like elastic moduli and dissipated energies which decrease during exposure, indicating stress relaxation and degradation. Two common structural sealants were tested. After testing, sections of the system specimens were subjected to tensile and shear tests for mechanical characterisation. Strengths and moduli are notably reduced by combined loading compared to those of reference and weathered specimens. Hardness and visual inspections of the bond correlate with the performance and bond characteristics. The approach introduced in this article provides a basis for life cycle assessment of SSG-systems. KW - Structural sealant glazing KW - Cyclic weathering KW - Mechanical loading KW - Artificial ageing KW - Durability assessment PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-519172 DO - https://doi.org/10.1080/00218464.2020.1840985 VL - 98 IS - 5 SP - 464 EP - 487 PB - Taylor & Francis Group AN - OPUS4-51917 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF ED - Rogge, Andreas ED - Meng, Birgit T1 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM - Beiträge zum 63. Forschungskolloquium Green Intelligent Building am 16. und 17. Oktober 2024 N2 - Zentrale gesellschaftliche Herausforderungen der kommenden Jahrzehnte sind der Klima- und Ressourcenschutz, insbesondere mit der Zielsetzung einer erheblichen Reduktion der Treibhausgasemissionen. Hierbei kommt dem Bauen eine besondere Bedeutung zu. Nach Angaben des UN Environment Programme ist der Bausektor für ca. 37 % der weltweiten CO2-Emissionen verantwortlich, wobei allein die Zementherstellung etwa 8 % der jährlichen Gesamtemissionen verursacht. Da in vielen Industriesektoren in naher Zukunft deutlich verminderte CO2-Emissionen zu erwarten sind, wird sich ohne schnelle und effiziente Entwicklungen der prozentuale Anteil der Zementherstellung an den Gesamtemissionen zukünftig noch deutlich erhöhen. Auch hinsichtlich des Ressourcenbedarfs im Bausektor steht die Weltgemeinschaft vor gewaltigen Herausforderungen, da der globale Trend zur Urbanisierung in Verbindung mit dem Bevölkerungswachstum in vielen Regionen eine dramatische Fortsetzung findet. Nach UN-Schätzungen werden im Jahr 2030 ca. 60 % aller Menschen in Städten leben. Schätzungen gehen davon aus, dass neben den heutigen Megastädten neue Zentren bisher unbekannten Ausmaßes insbesondere auf dem afrikanischen Kontinent entstehen werden (z. B. Lagos: 88 Mio. Einwohner, Kinshasa: 83 Mio., Daressalam: 74 Mio.). Die geografische Lage und die klimatischen Bedingungen bestimmen die Anforderungen und Probleme. Neben dem Neubau, der vor allem zentrales Thema in den aufstrebenden Zentren des globalen Südens sein wird, spielt auch das Bauen im Bestand im globalen Norden eine zentrale Rolle vor dem Hintergrund der Erreichung der Klima- und Nachhaltigkeitsziele. Bauwerke, z. B. als Wohnraum oder als bauliche Infrastruktur für Produktions-, Mobilitäts- und Konsumprozesse, haben seit Generationen eine zentrale Bedeutung bei der Sicherung elementarer Bedürfnisse der Menschen. Am Beispiel Deutschland lässt sich feststellen, dass aufgrund der Vielzahl und Größe der Gebäude die Bauwirtschaft der größte Verursacher von Stoffströmen ist. Neben den umgesetzten Materialmengen und benötigten Energieressourcen stammen zusätzlich auch nahezu 50 % des deutschen Reststoffaufkommens aus dem Baubereich. Das Bauwesen und die hier verwendeten Bauprodukte weisen sowohl unter materialtechnischer als auch mengenmäßiger Betrachtung ein weitgehend nicht ausgeschöpftes Potential bei der Verwendung rezyklierter Baustoffe und zusätzlich vorhandener, bisher ungenutzter industrieller Reststoffe als hochwertige Ersatzbaustoffe auf. Die zunehmenden Klimawandelfolgen fördern das gesellschaftliche Bewusstsein für die Auswirkungen anthropogener Aktivitäten auf unsere Umwelt und die regulierenden Eigenschaften der Natur. Naturbasierte und biomimetische Lösungen wie z. B. neue Möglichkeiten der Begrünung von Gebäudehüllen oder die gezielte Verbesserung der Wasserdurchlässigkeit versiegelter städtischer Flächen können das Stadtklima deutlich verbessern und die Resilienz gegenüber Extremwetterereignissen erhöhen. Auch wenn zukünftig vermehrt nachwachsende und rezyklierte Stoffe Eingang in die Bauprozesse finden werden, wird aus heutiger Sicht ein großer Teil der Materialen und Bauteile weiterhin zementbasiert, d. h. aus Beton oder Mörtel, sein. Diese Notwendigkeit ergibt sich aus der Kombination der vielfältigen günstigen Merkmale wie Form- und Gestaltbarkeit, Langlebigkeit, Robustheit, Flexibilität, Schallschutz, Wärmespeicherung, Nichtbrennbarkeit und der Umweltverträglichkeit. Hieraus ergibt sich die zwingende Notwendigkeit, die mit der Herstellung und der Verwendung von Beton und Mörtel bzw. ihrer Ausgangsstoffe verbundenen CO2-Emissionen idealerweise auf null zu senken. Hierzu werden von Wissenschaft und Industrie bereits seit Jahrzehnten erhebliche Anstrengungen unternommen, jedoch findet der Wandel hin zu nachhaltigeren Baustoffen und Bautechniken in der Praxis nur schleppend statt. Die Ursachen hierfür sind vielfältig, und dementsprechend kann eine signifikante Senkung der CO2-Emissionen durch den Bausektor nur erreicht werden, wenn eine Vielzahl von Strategien und Ansätzen untersucht und nach einer validen Bewertung und Evaluationsphase umgesetzt werden. Eine singuläre, allumfassende Lösung der adressierten Klimaschutz- und Nachhaltigkeitsfragen im Bausektor kann und wird es nicht geben. Vielmehr ist die Entwicklung breit gefächerter Baukästen diverser, bauaufsichtlich geregelter Lösungsansätze insbesondere auf den Gebieten klimaschonender Baustoffe, Ressourcenschonung und angepasster bzw. innovativer Technologien erforderlich. Die Bundesanstalt für Materialforschung und -prüfung (BAM) verfügt über mehr als 150 Jahre Erfahrung mit Bau- und Werkstoffen aller Art mit einem Schwerpunkt auf sicherheits- und dauerhaftigkeitsrelevanten Fragestellungen. Die generelle Festlegung der Forschungsthemen wird im Rahmen dieser grundlegenden Aufgabenstellung regelmäßig überprüft und auf die gesellschaftlich relevanten Fragestellungen ausgerichtet. Neben einer vorrangig anwendungsorientierten Forschung legen wir Wert darauf, unsere im Forschungsbereich erzielten Ergebnisse durch Technologietransfer und Mitwirkung in Standardisierung und Normung in die praktische Anwendung zu überführen. Die mittelfristige Festlegung unserer Forschungsschwerpunkte erfolgt in enger Abstimmung mit allen Interessengruppen. Im stark fragmentierten Bausektor mit ca. 80% Umsatzanteil kleinerer und mittlerer Unternehmen (KMU) sowie kleinteilig gegliederter Prozessketten mit wirtschaftlich voneinander unabhängigen Beteiligten (Planer, Baustoffhersteller, Bauunternehmer, Handwerker) sind dies vorrangig Forschungs- und Industrieverbände sowie Regelsetzungsgremien auf nationaler und internationaler Ebene. Die Umsetzung dieser Umfeldbetrachtungen in konkrete Aktivitäten erfolgt in BAM-internen, bereichsübergreifenden Strategieworkshops. In diesen wird auch die Anbindung der Material- und Technologiethemen an angrenzende Themenbereiche wie z. B. Fire Science, Additive Fertigung oder Leichtbau sichergestellt. Speziell auf dem Gebiet der Betonbauweisen haben wir auf diese Weise Forschungsschwerpunkte festgelegt, in welchen wir uns auf Basis unserer speziellen Kompetenzen eine besonders große Hebelwirkung unserer Ergebnisse auf die übergreifenden gesellschaftlichen Bedarfe versprechen. Somit liegt unser Fokus entsprechend unserer materialwissenschaftlichen Grundausrichtung auf dem Einsatz klimaschonender Materialen und Verarbeitungsprozesse, den Fragen der Ressourcenschonung, der Dauerhaftigkeit und Kreislaufwirtschaft und auf den technologischen Innovationen zum sicheren und produktiven Einsatz der Materialien. Unsere diesbezüglichen Forschungs- und Entwicklungsthemen haben wir zusammengefasst unter der Überschrift Green Intelligent Building. Für kurz- bis mittelfristig umsetzbare CO2-Einsparungen untersuchen wir, wie durch thermische Behandlung (Calcinierung) von Tonen Zementkomponenten mit ausreichend hoher Reaktivität hergestellt werden können. Da potenziell geeignete Tone weltweit in sehr großer Menge zur Verfügung stehen, können insbesondere solche calcinierten Tone einen nennenswerten Beitrag zur Senkung der CO2-Emissionen leisten. Darüber hinaus werden an der BAM verschiedene industrielle Reststoffe und biogene Aschen hinsichtlich ihrer Eignung als Zementkomponenten analysiert. Mit unserer Forschung wollen wir relevant zum übergreifenden Ziel der Bundesregierung hinsichtlich eines klimaneutralen Gebäudesektors bis zum Jahr 2045 beitragen. Langfristig können die mit der Bindemittelherstellung verbundenen CO2-Emissionen am stärksten gesenkt werden, indem Bindemittel ohne Portlandzementklinker („alternative Zemente“) verwendet werden. Zu diesen gehören u. a. Calciumsulfoaluminatzemente, Magnesiabinder sowie alkalisch aktivierte Bindemittel. Einige dieser Bindemittel lassen sich potenziell CO2-neutral oder nahezu CO2-neutral herstellen. An der BAM werden insbesondere alkalisch aktivierte Bindemittel untersucht, wobei neben der CO2-armen Herstellung auch die hervorragende technische Eignung in bestimmten Einsatzgebieten, wie z. B. in Reparaturmaterialien für Abwassersysteme, sowie der Einsatz als Stabilisator für Lehmbaustoffe im Fokus steht. Ein weiteres aktuelles Arbeitsfeld mit potenziell großem CO2-Einsparpotential ist der Einsatz von Biokohle als Zusatzstoff in Beton. Auf dem Gebiet des ressourcenschonenden Bauens forschen wir entsprechend unserem übergeordneten Auftrag „Sicherheit in Technik und Chemie“ insbesondere an der Wiederverwertung von Materialen mit konkreten Anforderungen an die Zuverlässigkeit, Dauerhaftigkeit und Umweltverträglichkeit. Im Hinblick auf die wesentlichen Massenströme arbeiten wir an sicheren Technologien für mineralische Bindemittel sowie sekundäre Gesteinskörnungen für Mörtel und Beton. Hierbei werden neben der umweltschonenden Wiederverwendung von Massenreststoffen auch wertvolle Ressourcen aus industriellen Reststoffströmen extrahiert und in neuen Baustoffen zielgerichtet eingesetzt wie z. B. Gipsabfälle, EOS- und LD-Schlacken, Papierasche oder biobasierte Reststoffe. Hieraus werden neue klimafreundliche Baustoffe, Gesteinskörnungen, Bindemittelsysteme, Zusatzstoffe und Zusatzmittel entwickelt und analysiert. Es geht um die stoffliche Bewertung und Weiterentwicklung dauerhafter, umweltsicherer und klimafreundlicher Baustoffe, wozu auch die Erforschung von Herstellungsstrategien, Schädigungsmechanismen und die Entwicklung von Performancekonzepten gehört. Zusammen mit Industrie- und Forschungspartnern werden gegenwärtig und zukünftig Forschungsprojekte, die zur Ressourcenschonung und Einsparung von CO2-Emissionen im Bauwesen beitragen, bearbeitet. Weitere Arbeiten zielen darauf ab, die Kreislaufwirtschaft durch digitale Innovationen, den Einsatz von KI und die Entwicklung digitaler Produktpässe zu fördern. Über die Mitarbeit in nationalen und internationalen Gremien bei der Normung und Regelsetzung in den Bereichen Kreislaufwirtschaft und für verschiedene Bauprodukte fördern wir den Wissenstransfer zwischen Forschung und Industrie. Eine weitere Strategie zur Verbesserung der Ressourceneffizienz und der Minimierung der Umweltwirkungen der Bauwirtschaft bietet die Entwicklung innovativer Technologien und Bauteile. An der BAM wird insbesondere an der additiven Fertigung (3D-Druck) mineralischer Baustoffe, der Anwendung hochwiderstandsfähiger Instandsetzungssysteme, dem Einsatz innovativer Materialien in funktionalen Fassaden und digitalen Verfahren zur Prozessoptimierung geforscht. Ein Beitrag zum klimaschonenden Bauen wird dabei sowohl durch neue Möglichkeiten des Designs, verbunden mit Materialeinsparungen oder der intelligenten Integration weiterer Funktionalitäten erreicht als auch durch eine erhöhte Dauerhaftigkeit der Materialien verbunden mit einer Lebensdauerverlängerung der Bauwerke. Die BAM beschäftigt sich mit der Optimierung unterschiedlicher additiver Fertigungsverfahren sowohl der Pulverbett- als auch der Extrusionstechnologie. Dabei steht die ganzheitliche Betrachtung des neuen Fertigungsprozesses im Fokus, die die Entwicklung klimaschonender Druckmaterialien, die gezielte Optimierung der rheologischen Eigenschaften von mineralischen Baustoffsystemen, die kontinuierliche Prozessüberwachung mittels In-Situ-Monitoring, die Prozesssteuerung durch digitale Modelle sowie die abschließende Qualitätskontrolle vereint. Durch die ganzheitliche Betrachtung des Fertigungsprozesses werden zentrale Grundlagen geschaffen, um für die großtechnische Anwendung zukünftige Normen und Standards für den 3D-Betondruck zu erarbeiten und der Industrie bereitzustellen. Digitale modell- und/oder datenbasierte Methoden spielen grundsätzlich eine entscheide Rolle bei der Optimierung von Prozessen und Strukturen. Sie ermöglichen eine virtuelle Produktentwicklung von baustoff- oder strukturoptimierten Bauteilen sowie Prozessen und tragen damit wesentlich zur Steigerung der Ressourceneffizienz bei. Die Grundlage bilden Modelle, die das Material-, Struktur- oder Prozessverhalten abhängig von bestimmten Parametern (zum Beispiel Zeit, Temperatur, Zusammensetzung, Belastung) vorhersagen. Basierend auf gemessenen Daten werden die Modelle kontinuierlich verbessert, so dass ein virtueller Zwilling entsteht. Neben der Entwicklung solcher Zwillinge für unterschiedliche Anwendungen werden an der BAM Methoden entwickelt, die zusätzlich die Unsicherheiten sowohl in den Messdaten als auch im Modell berücksichtigen und eine Bewertung der Prognosequalität der Zwillinge erlauben. Dies schafft die Grundlage zur Verwendung in Standards und Normen. T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM Green Intelligent Building CY - Berlin, Germany DA - 16.10.2024 KW - Beton KW - Green Intelligent Building KW - Klimafreundliche Bindemittel KW - Chemie der Bindemittel KW - Ressourcenschonung KW - Innovative Technologien KW - Digitalisierung im Bauwesen KW - Bauteile KW - Bauwerke PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-613383 SN - 978-3-9818564-7-7 DO - https://doi.org/10.26272/opus4-61338 SP - 1 EP - 301 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-61338 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Recknagel, Christoph A1 - Spitzer, Stefan A1 - Hoppe, Johannes A1 - Wenzel, Norman A1 - Pirskawetz, Stephan T1 - SENSO JOINT - An innovative sensor system for a sustainable joint design of concrete pavements N2 - Inacceptable capability and durability of joint sealing systems but also inadequate traffic performance (noise emission; overrolling comfort) up to traffic safety aspects reflect the still enormous demand for data-based description of concrete pavements performance under heavy loading conditions. Especially the deformation behavior of concrete pavement slabs in the joint region in consideration of new pavement construction types and improved concrete mixtures meanwhile established but also under the steeply rising traffic loads is not sufficiently explored. To create a data basis for advanced design rules, evaluation methods and product standards - and with it to improve quality, durability and finally sustainability of pavements - an innovative 3-D sensor system SENSO JOINT adapted to german roadworking requirements and suitable for heavy-duty operating conditions was developed. The contribution introduced describes the development of an extensive technical solution based on the analysis of decisive loads, interactions and boundary conditions. Based on calibration data, results of laboratory testing and finally field-testing on different concrete pavement construction types the outcome of a multi-level evaluation process shall introduce the potential of the new sensor system. T2 - 9th International Conference on Maintenance and Rehabilitation of Pavements (Mairepav9) CY - Online meeting DA - 01.07.2020 KW - Concrete pavements KW - Sustainable joint sealing KW - Load quantification KW - Innovative measurement technology KW - Field validation KW - Performance design for joint systems PY - 2020 SN - 978-3-030-48678-5 SN - 978-3-030-48679-2 DO - https://doi.org/10.1007/978-3-030-48679-2 SN - 2366-2557 VL - 76 SP - 191 EP - 199 PB - Springer Nature Switzerland AG CY - Switzerland AN - OPUS4-51965 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Weise, Frank A1 - Stelzner, Ludwig A1 - Recknagel, Christoph A1 - Pittrich, Tim A1 - Neugum, Tim A1 - Hering, Marcus A1 - Fiedler, Georg A1 - Thiele, Marc A1 - Simon, Patrick A1 - Maack, Stefan T1 - 63. DAfStb-Forschungskolloquium in der BAM - Themenblock 5: Bauteile und Bauwerke N2 - Ein weiterer Fokus des 63. DAfStb-Forschungskolloquiums (Tagungsband: DOI 10.26272/opus4-61338) lag auf den Bauteil- und Bauwerksuntersuchungen. Insbesondere wurde hier ein Einblick in die Forschungsaktivitäten in den BAM-Themenfeldern „Infrastruktur“ und „Energie“ gegeben. Thematisch wird dabei der Bogen von der Dauerhaftigkeit von Betonfahrbahndecken über die Extrembeanspruchung von Bauteilen und Bauwerken mittels Brand und Impact bis zum Bauwerksmonitoring und der Zustandsanalyse von Bestandsbauwerken gespannt. T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM Green Intelligent Building CY - Berlin, Germany DA - 16.10.2024 KW - Dauerhaftigkeit von Betonfahrbahndecken KW - Alkali-Kieselsäurereaktion KW - Brand Impact KW - Bauwerksmonitoring PY - 2025 SN - 0005-9846 VL - 75 IS - 4 SP - 138 EP - 140 PB - concrete content UG CY - Schermbeck AN - OPUS4-63071 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Andrés Arcones, Daniel T1 - Uncertainty Quantification and Model Extension for Digital Twins of Bridges through Model Bias Identification N2 - The creation and use of Digital Twins of existing structures, such as bridges, implies precise digital replicas that accurately mirror their physical counterparts. Ensuring the trustworthiness of Digital Twins and facilitating informed decision-making necessitates a robust approach to Uncertainty Quantification (UQ). A suitable model-updating scheme is key in preserving the quality and robustness of simulation-based Digital Twins. Model bias, stemming from discrepancies between computational models and real-world systems, poses a significant challenge in achieving this goal. This study delves into the challenges posed by model bias within Bayesian updating of Digital Twins of bridges. Two alternative model bias identification methods —a modularized version of Kennedy and O’Hagan’s approach and another one based on Orthogonal Gaussian Processes — are evaluated in comparison with the classical Bayesian inference framework. A key innovation lies in the modification of the aforementioned approaches to incorporate additional information into the Digital Twin framework via the bias term. This enables the extension of the model non-intrusively, leveraging large pools of data inherent in Digital Twins. The study showcases the potential of this approach to correct predictions, quantify uncertainties, and enhance the system with previously untapped information. This underscores the importance of everaging available data within Digital Twins to identify deficiencies and guide potential future model improvements. T2 - ECCOMAS CONGRESS 2024 9th European Congress on Computational Methods in Applied Sciences and Engineering CY - Lisbon, Portugal DA - 03.06.2024 KW - Digital Twin KW - Simulation Models KW - Uncertainty Quantification KW - Model Bias PY - 2024 AN - OPUS4-61023 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Andrés Arcones, Daniel A1 - Weiser, M. A1 - Koutsourelakis, F. A1 - Unger, Jörg F. T1 - A Bayesian Framework for Simulation-based Digital Twins of Bridges N2 - Simulation-based digital twins have emerged as a powerful tool for evaluating the mechanical response of bridges. As virtual representations of physical systems, digital twins can provide a wealth of information that complements traditional inspection and monitoring data. By incorporating virtual sensors and predictive maintenance strategies, they have the potential to improve our understanding of the behavior and performance of bridges over time. However, as bridges age and undergo regular loading and extreme events, their tructural characteristics change, often differing from the predictions of their initial design. Digital twins must be continuously adapted to reflect these changes. In this article, we present a Bayesian framework for updating simulation-based digital twins in the context of bridges. Our approach integrates information from measurements to account for inaccuracies in the simulation model and quantify uncertainties. Through its implementation and assessment, this work demonstrates the potential for digital twins to provide a reliable and up-to-date representation of bridge behavior, helping to inform decision-making for maintenance and management. T2 - Eurostruct 2023 CY - Vienna, Austria DA - 25.09.2023 KW - Digital Twins KW - Bayesian Inference KW - Bridge Monitoring KW - Uncertainty Quantification PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-586803 UR - https://eurostruct.org/eurostruct-2023/ DO - https://doi.org/10.1002/cepa.2177 SN - 2509-7075 VL - 6 IS - 5 SP - 734 EP - 740 PB - Ernst & Sohn CY - Berlin AN - OPUS4-58680 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Oesch, Tyler A1 - Weise, Frank A1 - Meinel, Dietmar A1 - Gollwitzer, Christian T1 - Quantitative in-situ analysis of water transport in concrete completed using X-ray computed tomography N2 - This paper describes a novel methodology for quantitative in-situ moisture measurement without tracking agents using X-ray computed tomography (XCT). The high levels of grey-scale precision required for the measurement of moisture without tracking agents resulted in the need for an additional image calibration procedure to correct for water-related X-ray scattering and for equipment-variability related artefacts arising during in-situ testing. This calibration procedure was developed on the basis of existing principles of XCT image cor-rection. Resulting images of moisture distribution exhibit a high level of agreement with expected material behaviour. This research demonstrated that XCT can be successfully used to measure both moisture-front movement over time and changes in 3D moisture distribution within samples. This approach to moisture measurement lays the groundwork for the planned future investigation of the interaction between cracking induced by varying chemical and mechanical processes and water transport in concrete. KW - X-ray computed tomography (XCT) KW - In-situ testing KW - Water transport KW - Quantitative moisture measurement KW - Concrete PY - 2019 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-474395 DO - https://doi.org/10.1007/s11242-018-1197-9 SN - 1573-1634 VL - 127 IS - 2 SP - 371 EP - 389 PB - Springer Netherlands AN - OPUS4-47439 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Pirskawetz, Stephan A1 - Gründer, Klaus-Peter A1 - Kadoke, Daniel A1 - Unger, Jörg F. T1 - Überwachung von Stahlbetonbrücken - Ein Modellprojekt N2 - Die Brücken im Netz der Bundesverkehrswege sind überwiegend in einem ausreichenden bis guten Zustand. Allerdings steigt der Unterhalts- und Sanierungsaufwand aufgrund des inzwischen hohen Alters vieler Brücken sowie des ständig wachsenden Schwerlastverkehrs. Techniken zur Einschätzung der verbleibenden Lebensdauer von Brücken sowie zur dauerhaften Beobachtung des Tragverhaltens bzw. des Erfolges von Sanierungsmaßnahmen werden daher für den sicheren und wirtschaftlichen Betrieb dringend benötigt. Zur Evaluierung dafür geeigneter holistischer Ansätze wurde in der BAM das Projekt BLEIB - Bewertung, Lebensdauerprognose und Instandsetzung von Brückenbauwerken - ins Leben gerufen. Ein zentrales Ergebnis des Projektes ist eine extern vorgespannte Stahlbetonbrücke als Zweifeldträger mit einer Gesamtlänge von 24 m, die für den Test verschiedenster Sensorsysteme, zur Validierung numerischer Modelle und zur Erprobung von Sanierungs- und Verstärkungsmaßnahmen entwickelt wurde. Für die Simulation unterschiedlicher Schädigungsgrade kann die Vorspannung der Brücke variiert werden. Die Brücke wird mit beweglichen Gewichten belastet und über einen Shaker zum Schwingen angeregt. Das Brückenmodell wurde bewusst geschädigt, indem die Vorspannung der Struktur erstmalig schrittweise bis auf null reduziert wurde. Unter der Eigenlast verformte sich die Brücke, wodurch eine Rissbildung im Beton einsetzte. Die Zugspannung, die zuvor durch die Vorspannung aufgenommen wurde, übernahm Schritt für Schritt der Beton. Als die Zugspannungen die relativ geringe Zugfestigkeit des Betons überstiegen, begann dieser zu reißen und die schlaffe Bewehrung der Struktur nahm die Spannungen auf. Dieser Versuch wurde unter anderem von Schallemissionsmessungen begleitet. Der Rissbildungsprozess konnte damit, bei gleichzeitiger Aufzeichnung der Vorspannung, früh detektiert und die Risse geortet werden. Die Ergebnisse korrelieren gut mit den Ergebnissen der stereophotogrammetrischen Verformungsmessungen der Struktur. T2 - 22. Kolloquium Schallemission und 3. Anwenderseminar Zustandsüberwachung mit geführten Wellen CY - Karlsruhe, Germany DA - 27.03.2019 KW - Brückenmonitoring KW - Schallemissionsanalyse PY - 2019 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-477878 SN - 978-3-947971-00-8 VL - 169 SP - 1 EP - 5 PB - Deutsche Gesellschaft für Zerstörungsfreie Prüfung (DGZfP) CY - Berlin AN - OPUS4-47787 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bartels, Jan-Hauke A1 - Xu, Ronghua A1 - Kang, Chongjie A1 - Herrmann, Ralf A1 - Marx, Steffen T1 - Experimental Investigation on the Transfer Behavior and Environmental Influences of Low-Noise Integrated Electronic Piezoelectric Acceleration Sensors N2 - Acceleration sensors are vital for assessing engineering structures by measuring properties like natural frequencies. In practice, engineering structures often have low natural frequencies and face harsh environmental conditions. Understanding sensor behavior on such structures is crucial for reliable masurements. The research focus is on understanding the behavior of acceleration sensors in harsh environmental conditions within the low-frequency acceleration range. The main question is how to distinguish sensor behavior from structural influences to minimize errors in assessing engineering structure conditions. To investigate this, the sensors are tested using a long-stroke calibration unit under varying temperature and humidity conditions. Additionally, a mini-monitoring system configured with four IEPE sensors is applied to a small-scale support structure within a climate chamber. For the evaluation, a signal-energy approach is employed to distinguish sensor behavior from structural behavior. The findings show that IEPE sensors display temperature-dependent nonlinear transmission behavior within the low-frequency acceleration range, with humidity having negligible impact. To ensure accurate engineering structure assessment, it is crucial to separate sensor behavior from structural influences using signal energy in the time domain. This study underscores the need to compensate for systematic effects, preventing the underestimation of vibration energy at low temperatures and overestimation at higher temperatures when using IEPE sensors for engineering structure monitoring. KW - Acceleration sensors KW - Environmental influence KW - IEPE KW - Structural Health Monitoring KW - Low-frequency shaker PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-594623 UR - https://www.mdpi.com/2673-8244/4/1/4/ DO - https://doi.org/10.3390/metrology4010004 SN - 2673-8244 VL - 4 IS - 1 SP - 46 EP - 65 PB - MDPI CY - Basel AN - OPUS4-59462 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Klimek, André A1 - Stelzner, Ludwig A1 - Hothan, Sascha A1 - Zehfuß, Jochen T1 - Influence of thermal strain on concrete spalling N2 - Understanding the susceptibility to spalling of concrete members in case of fire is important to evaluate the residual load-bearing capacity. The investigations of the spalling phenomenon of a concrete mixture using real scale members are necessary but expensive to carry out. Reducing the specimen size leads to an increase of boundary effects that can result in a reduced spalling or absence of spalling. In this study, fire tests were carried out on unrestrained, single-sided exposed, cuboid shaped specimens (0.6 m x 0.6 m x 0.29 m) as well as unrestrained and steel ring restrained cylindrical specimens (Ø = 0.47 m, h = 0.29 m), which induce different boundary conditions. These fire tests were carried out on two ordinary concrete mixtures. The two mixtures differ only in the type of aggregates (quartz gravel and basalt grit) and were used to investigate the influence of the thermal expansion of the aggregate on the spalling behaviour of the concrete. The results show a significant increase of the spalling depth due to the restrained thermal expansion achieved by the applied steel rings. Additionally, the type of aggregate has a direct influence on the spalling behaviour of a concrete mixture. The reduction of the boundary effects by the steel rings recreate the test conditions in the centre of a large concrete member. Thus, this type of specimen is suitable to determine the susceptibility to spalling of a material (screening-tests) as preliminary investigations to full scale fire tests. KW - Spalling KW - Concrete KW - Fire test KW - Restraint KW - Screening test PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-593350 DO - https://doi.org/10.1617/s11527-023-02274-x VL - 57 SP - 1 EP - 14 PB - Springer AN - OPUS4-59335 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Glienke, R. A1 - Kalkowsky, F. A1 - Hobbacher, A. F. A1 - Holch, A. A1 - Thiele, Marc A1 - Marten, F. A1 - Kersten, R. A1 - Henkel, K.-M. T1 - Evaluation of the fatigue resistance of butt‑welded joints in towers of wind turbines - A comparison of experimental studies with small scale and component tests as well as numerical based approaches with local concepts N2 - Wind turbines are exposed to a high number of load cycles during their service lifetime. Therefore, the fatigue strength verification plays an important role in their design. In general, the nominal stress method is used for the fatigue verification of the most common used butt-welded joints. The Eurocode 3 part 1–9 is the current design standard for this field of application. This paper presents recent results of fatigue tests on small-scaled specimens and large components with transverse butt welds to discuss the validity of the FAT-class. Furthermore, results from numerical simulations for the verification with the effective notch stress and the crack propagation approach are used for comparison. Based on the consistency between the numerical results and the fatigue tests, the influence of the seam geometry on the fatigue resistance was investigated. Finally, a prediction of the fatigue strength of butt-welded joints with plate thicknesses up to 80 mm was carried out. KW - Transverse butt weld KW - Weld imperfections KW - Wind turbine tower KW - Fatigue strength KW - Local approaches KW - Large components KW - Wind energy PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-596648 DO - https://doi.org/10.1007/s40194-023-01630-3 SN - 1878-6669 SP - 1 EP - 26 PB - Springer CY - Berlin AN - OPUS4-59664 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hirsch, T. A1 - Voigt, Marieke A1 - Lehmann, Christian A1 - Meng, Birgit A1 - Lothenbach, B. T1 - Impact of autoclaving on the phase assemblage of Portland cement: Experiment and thermodynamic modelling N2 - Even after autoclaving for 2 weeks in the temperature range of 120 to 200 °C, CEM I paste with a water-to-cement ratio of 0.5 still contains some low-crystalline C-S-H. The conversion of low-crystalline C-S-H to crystalline is faster with increasing temperature. The observed low-crystalline and crystalline C-S-H phases (reinhardbraunsite, jaffeite) indicate that the sampleshave not reached equilibrium yet under these experimental conditions. However, there is a good agreement between experiment and thermodynamic modelling for the other solids indicating that the used datasets are suitable for this application. T2 - 16th International Congress on the Chemistry of cement 2023 - ICCC2023 CY - Bangkok, Thailand DA - 18.09.2023 KW - Zement KW - Thermodynamik KW - Phasenzusammensetzung KW - Mineralogie KW - Modellierung PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-589779 UR - https://iccc2023.org VL - 1 SP - 619 EP - 621 AN - OPUS4-58977 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wedel, F. A1 - Pitters, S. A1 - Herrmann, Ralf A1 - Schneider, Ronald A1 - Hille, Falk A1 - Hindersmann, I. T1 - Guideline for the strategic application of monitoring of road bridges in Germany N2 - Engineering structures are an important part of our transport infrastructure. Their failure is associated with high safety risks and economic damage. Ensuring the availability of these constructions and guaranteeing their operational safety are thus important tasks. Currently, maintenance of engineering structures is a reactive process and therefore not yet a predictive process. Every 3 to 6 years, the structures are visually inspected, all damages are documented and a condition grade is assigned to the structure based on the detected damages. Continuous data-providing methods such as monitoring are used only very occasionally. With the help of monitoring, condition data about the structures are continuously collected, which can be used for a better assessment of the structures. On the one hand, this would increase safety of engineering structures, and on the other hand, it makes the shift towards predictive maintenance management based on real-time data and predictions, where the onset of damage is detected before it occurs, possible in the first place. Monitoring plays therefore an important role in the management of the infrastructure. It is a crucial a step towards the digitalisation of our infrastructure and existing processes. Although there are many use cases for monitoring that have already been successfully implemented, monitoring is not yet widely used by German road authorities due to several challenges that were also identified within the scope of the project. Therefore, a guide has been developed in which the current obstacles related to monitoring are identified and possibilities for integrating monitoring into existing processes are offered. To ensure optimal alignment with the needs of road authorities, both an online survey and a workshop have been conducted. The results are summarised in a brochure that is made available to authorities to improve the use of monitoring in Germany. This paper presents the guideline and the brochure. T2 - 10th European Workshop on Structural Health Monitoring (EWSHM 2024) CY - Potsdam, Germany DA - 10.06.2024 KW - Verkehrsinfrastrukturen KW - Engineering Structures KW - Bridges KW - Structural Health Monitoring KW - Guideline PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-612821 UR - https://www.ndt.net/search/docs.php3?id=29582 DO - https://doi.org/10.58286/29582 SN - 1435-4934 VL - 29 IS - 7 SP - 1 EP - 8 PB - NDT.net GmbH & Co. KG CY - Mayen AN - OPUS4-61282 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Pirskawetz, Stephan A1 - Thiele, Marc A1 - Löhr, Manuel A1 - Loewe, Anna A1 - Degener, Sebastian A1 - Herrmann, Ralf T1 - Acoustic emission for monitoring of fatigue damage in concrete elements of wind turbine towers N2 - Wind energy has become an important player in the energy transition in Germany. Towers of onshore wind turbines are often designed as hybrid structures: the lower part is made of prestressed concrete whereas the upper part is made of steel tubes. The tall structures are permanently subjected to cyclic loads. A research project of BAM as part of the joint project WinConFat - Structure focusses on the evelopment of techniques to monitor fatigue damage evolution in the concrete part. Results of a previous project show that a combination of ultrasonic and acoustic emission testing can give an indication for critical conditions near the end of the fatigue life of the concrete. In the ongoing project acoustic emission sensors have been installed at the base and at the transition piece between concrete and steel of a hybrid wind turbine tower. Beside of acoustic emission measurement the sensor spacing allows for measuring the concrete ultrasonic velocity along the circumference in both levels. Additional measurements like strain, temperature, inclination, or acceleration allow for comparison of environmental loads and change of acoustic properties of the concrete. The paper focusses on first acoustic measurements recorded since December 2023 in comparison to operating data of the wind turbine. T2 - EWGAE2024: 36th Conference of the European Working Group on Acoustic Emission CY - Potsdam, Germany DA - 18.09.2024 KW - Concrete fatigue monitoring KW - Acoustic emission KW - Ultrasound KW - Hybrid wind turbine tower PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-612197 DO - https://doi.org/10.58286/30234 SN - 1435-4934 VL - 29 IS - 10 SP - 1 EP - 9 AN - OPUS4-61219 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Unger, Jörg F. A1 - Tamsen, Erik A1 - Agrawal, A. A1 - Koutsourelakis, P.-S. ED - Rogge, Andreas ED - Meng, Birgit T1 - Von Messdaten zum optimierten Bauteil durch Kombination von Material- und Strukturdesign N2 - Die Entwicklung eines optimierten Designs für Bauwerke erfordert die Berücksichtigung sowohl des Materials als auch des Strukturdesigns. Ziel des Beitrages ist die Vorstellung eines Designprinzips basierend auf automatisierten Workflows, das am Beispiel eines Biegebalkendesign zur Reduzierung des Treibhauspotenzials vorgestellt wird. Eine ganzheitliche Optimierung berücksichtigt Material- und Strukturdesign. Es werden physikalische Modelle mit Ansätzen aus dem maschinellen Lernen kombiniert, die mit experimentellen Daten kalibriert bzw. trainiert werden. Eine besondere Bedeutung hat dabei die Berücksichtigung von Unsicherheiten. T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM Green Intelligent Building CY - Berlin, Germany DA - 16.10.2024 KW - Materialdesign KW - Strukturdesign PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-613003 SN - 978-3-9818564-7-7 SP - 209 EP - 217 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-61300 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Telong, Melissa A1 - Zoriyatkha, Aida A1 - Pirskawetz, Stephan A1 - Meng, Birgit ED - Rogge, Andreas ED - Meng, Birgit T1 - Beton-Datenmanagement anhand von wissensbasierten Datenstrukturen unter Nutzung von Ontologien und Wissensgraphen N2 - Im Rahmen der Entwicklung von Betonrezepturen, bei der Betonherstellung und während der Nutzungsphase im Bauwerk, wird eine Vielzahl von Materialdaten generiert. LeBeDigital (Lebenszyklus von Beton - Ontologie- Entwicklung für die Prozesskette der Betonherstellung) ist ein Verbundprojekt innerhalb der Initiative Plattform Material Digital. Das Projekt zielt darauf ab, eine Struktur für Betonmaterialdatenbanken zu entwickeln, die dem FAIR-Prinzip folgt und sowohl praxisnah als auch flexibel genug ist, um zukünftige Entwicklungen in der Betonforschung und -produktion zu unterstützen. Ontologien stellen ein geeignetes Werkzeug zur Generierung von Wissensgraphen dar, um Workflows zur automatisierten Datenerfassung und zur semantischen Datenabfrage zu gestalten. Daher ist die Erarbeitung betonspezifischer Ontologien zentraler Bestandteil des Verbundprojektes, das dazu beitragen will, die Vorrausetzungen für eine Teilhabe der Betonbranche am digitalen Wandel im Bereich der Materialforschung zu sichern. T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM Green Intelligent Building CY - Berlin, Germany DA - 16.10.2024 KW - Beton-Datenmanagement PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-612984 SN - 978-3-9818564-7-7 SP - 201 EP - 208 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-61298 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Herrmann, Ralf A1 - Hille, Falk A1 - Pitters, S. A1 - Ramasetti, Eshwar Kumar A1 - Schneider, Ronald A1 - Wedel, F. A1 - Hindersmann, I. ED - Rogge, Andreas ED - Meng, Birgit T1 - Föderiertes Datenmanagement von Monitoringdaten aus Structural Health Monitoring Anwendungen und daraus gewonnenen Trainingsdaten bei Spannbetonbrücken N2 - Beim Structural Health Monitoring entstehen eine Vielzahl von Daten, Metadaten und Modellen mit hohem Wert für die Beurteilung des Bauwerkszustands und der Prognose von Veränderungen. Kontinuierlich anwachsende Datenbestände müssen nachhaltig geteilt, genutzt und über die Bauwerkslebensdauer archiviert werden. Dabei stellen die Vielfalt der Messaufgaben, die Heterogenität der Daten, die dezentrale Erfassung und z. T. der Umfang eine Herausforderung für die beteiligten Akteure dar. Für den Datentransfer der Monitoringdaten zwischen der Straßenbauverwaltung und den Monitoringausführenden wird ein flexibles Abstimmungsverfahren vorgeschlagen und ein Lösungskonzept für ein föderiertes Datenmanagement skizziert. Eine weitere Herausforderung stellt die bauwerksübergreifende Zusammenstellung von Trainingsdaten für konkrete KI-Anwendungen dar. T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM Green Intelligent Building CY - Berlin, Germany DA - 16.10.2024 KW - Structural Health Monitoring PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-612902 SN - 978-3-9818564-7-7 SP - 178 EP - 185 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-61290 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hille, Falk A1 - Herrmann, Ralf A1 - Pitters, S. A1 - Hindersmann, I. A1 - Schneider, Ronald A1 - Wedel, F. ED - Rogge, Andreas ED - Meng, Birgit T1 - Leitfaden für den strategischen Einsatz von Monitoring an Straßenbrücken N2 - Für die Anwendung von Structural Health Monitoring (SHM) im Rahmen des Managements von Straßenbrü-cken wurde zur Unterstützung von Straßenbauverwaltungen, Ingenieurbüros, Bauunternehmen und weiteren Akteuren die Erstellung eines Leitfadens initiiert. Dieser Leitfaden stellt typische Anwendungsfälle für Monito-ring vor und schlägt für diese bewährte Herangehensweisen vor. Darüber hinaus bietet der Leitfaden Empfeh-lungen für Ausschreibung und Vergabe von Monitoringleistungen, eine Anleitung zur Bewertung des wirt-schaftlichen Nutzens von SHM, Hinweise zur optimal einsetzbaren Messtechnik sowie einen Ansatz für das Datenmanagement zur Integration der Monitoringdaten in das Brückenmanagement. T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM Green Intelligent Building CY - Berlin, Germany DA - 16.10.2024 KW - Leitfaden KW - Monitoring KW - Straßenbrücke PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-612931 SN - 978-3-9818564-7-7 SP - 186 EP - 191 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-61293 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Rosenbusch, Sjard Mathis A1 - Balzani, D. A1 - Unger, Jörg F. T1 - Regularization of softening plasticity models for explicit dynamics using a gradient-enhanced modified Johnson–Holmquist model N2 - The behavior of concrete under high strain rates is often described by plasticity models with softening, which is modeled by a reduction of the yield surface as a function of the local equivalent plastic strain. Many of these models are local and therefore produce mesh-dependent results. In this contribution, the gradient-enhancement of such models is investigated to mitigate the mesh-dependency. First, the mesh-dependency of these local formulations based on the analysis with a modified JH2 model as a representative for these constitutive formulations is demonstrated using a one-dimensional benchmark example. In the benchmark, the width of the damaged zone decreases upon mesh-refinement and the dissipated plastic energy tends to zero. It is further shown that a significantly small safety factor for the critical time step is needed in order to achieve accurate results for the benchmark example. The first investigated gradient-enhancement approach replaces the equivalent local plastic strain with its nonlocal counterpart. The enhancement is based on the inclusion of inertia and damping to the additional Helmholtz equation which enables the use of the central difference method as an explicit solver. This method successfully distributes the damage over several elements, however, the local equivalent plastic strain still localizes into one cell. The inclusion of hardening with respect to the local equivalent plastic strain inhibits the localization and the dissipated plastic energy converges with mesh-refinement. This is further confirmed in a two-dimensional wedge-splitting experiment and a four-point bending test where the damage pattern produced by the local model is mesh-dependent as well and the dissipated plastic energy tends to zero with mesh-refinement. The proposed nonlocal model with hardening results in a consistent damage pattern and the dissipated plastic energy converges. Furthermore, the nonlocal model with hardening is less sensitive to time step refinement, such that computational efficiency can be improved compared to the local model. The numerical experiments are implemented using the free open source tool FEniCSx and have been made available on Zenodo. KW - Gradient plasticity KW - Explicit dynamics KW - JH2 model KW - Concrete modeling KW - FEniCS KW - Mesh convergence KW - Time step convergence PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-630453 DO - https://doi.org/10.1016/j.ijimpeng.2024.105209 SN - 1879-3509 VL - 198 SP - 1 EP - 18 PB - Elsevier Ltd. CY - Schweiz AN - OPUS4-63045 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Ji, Y. A1 - Pott, U. A1 - Mezhov, Alexander A1 - Rößler, Ch. A1 - Stephan, D. T1 - Modelling and experimental study on static yield stress evolution and structural build-up of cement paste in early stage of cement hydration N2 - Static yield stress is crucial for concrete, especially for 3D printed concrete, as it determines whether the bottom layer can support the load of the subsequent layers or withstand any potential impulses. A better understanding of the evolution of the static yield stress and its changing mechanism is therefore needed. Under the assumption that hydrate formation follows fractal patterns, this work proposes a model for simulating static yield stress that links the hydration process and bridging possibility. To validate the model, parameters were first obtained from the BNG (Boundary Nucleation Growth) equation fitted with calorimetry data, and the relation of associated hydration rates to sound speed variation rate was analyzed. Results showed that the proposed model predicts well the static yield stress obtained with a penetration test, under varying water-cement ratios and accelerator conditions. The fitted parameter β was found to correlate with size and morphology of the hydration products, suggesting that the model can not only simulate the static yield stress, but also capture the structural build-up information. Furthermore, the decrease in fractal-related β implies that more compact hydrates are formed during hydration. KW - Static yield stress KW - Fractal pattern KW - Hydration process KW - Bridging possibility PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-623503 DO - https://doi.org/10.1016/j.cemconres.2024.107710 SN - 1873-3948 VL - 187 SP - 1 EP - 15 PB - Elsevier Ltd. CY - Schweiz AN - OPUS4-62350 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Rosenbusch, Sjard Mathis A1 - Diercks, Philipp A1 - Kindrachuk, Vitaliy A1 - Unger, Jörg F. T1 - Integrating custom constitutive models into FEniCSx: A versatile approach and case studies N2 - The development and integration of user-defined constitutive relationships into finite element (FE) tools using standardized interfaces play a pivotal role in advancing the capabilities of FE solvers for structural mechanics applications. While commercial FE solvers like Abaqus and Ansys have designed their interfaces to provide custom stresses, tangents, and updated history variables, the open-source solver FEniCSx remains efficient only when the constitutive update has an analytical representation. This restricts the application of FEniCSx for non-linear structural mechanics. Since FEniCSx has become a powerful and popular open-source tool for solving partial differential equations, particularly due to its automatic computation of Hessians, we aim to develop a generalized interface to enhance its capability for constitutive modeling. This approach will address complex constitutive equations that require iterative solutions at the quadrature point level. Specific implementation challenges, such as using return-mapping procedures, can then be managed commonly. The provided interface for custom constitutive models offers a versatile way to implement them in various languages, including C++, Python, Rust, and Fortran. Finally, with UMATs for viscoplastic models as an example, we demonstrate how existing user subroutines can be incorporated into the interface and utilized within the FEniCSx framework. KW - Finite element method KW - Constitutive models KW - FEniCSx KW - UMAT KW - Rust KW - Python KW - C++ PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-630439 DO - https://doi.org/10.1016/j.advengsoft.2025.103922 SN - 0965-9978 VL - 206 SP - 1 EP - 11 PB - Elsevier CY - Amsterdam AN - OPUS4-63043 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Ji, Y. A1 - Mezhov, Alexander A1 - Wang, S. A1 - Stephan, D. T1 - Influence of polycarboxylate superplasticizers with different molecular structures on rheological properties of glass bead suspension at different resting times N2 - Using an inert glass bead suspension, the study explores the interaction between various PCE superplasticizers, ions and investigates how it affects rheological performance during resting. To understand the underlying mechanisms, surface charge properties, adsorption, aggregates amount, and size of PCE during resting were measured. Results showed that yield stress increased with time, mainly when a high PCE dosage was used, and the modulus from strain sweep experiments agreed with the yield stress variations. The increase in zeta potential value and decrease in aggregate amount explain the decrease in yield stress in the non-PCE sample but are inconsistent with the increase in yield stress in presence of PCE. The PCE clusters’ size increases during resting, and increasing PCE adsorption does not disperse the glass bead particles. In addition, compared to the amount of carboxylate group, the molecular weight of PCE is more dominant in increasing the yield stress during resting. The increase in yield stress could be explained by the increase in the bridging and depletion forces due to the increasing size of the PCE cluster. Another possible reason is that non-adsorbed PCE clusters may form a polymer network that restricts the movement of the particles. KW - Glass bead KW - Rheological performance KW - PCE superplasticizers KW - Ion KW - Resting time PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-617609 DO - https://doi.org/10.1016/j.colsurfa.2024.133583 SN - 0927-7757 VL - 688 IS - 133583 SP - 1 EP - 12 PB - Elsevier B.V. CY - Schweiz AN - OPUS4-61760 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schwettmann-Lui, Kim A1 - Nytus, Nina A1 - Weigel, Sandra A1 - Radenberg, Martin A1 - Stephan, Dietmar T1 - Effect of multiple-repeated aging and rejuvenation processes on bitumen properties evaluated with physical and chemical tests and multivariate analysis methods N2 - This paper presents laboratory experiments on repeated bitumen aging and rejuvenation processes to assess multiple reuse feasibility. Three 50/70 penetration-graded bitumen samples were reused with four different rejuvenators without adding virgin binder. The experiments continued until significant material changes, such as inhomogeneities and increased stickiness, prevented reliable characterization. After each rejuvenation and aging process, physical and chemical properties were analyzed, resulting in a comprehensive dataset. Results indicate that the reuse of pure rejuvenators, without incorporating virgin binder, is limited. Cyclic reuse depends heavily on the rejuvenator and its interaction with the binder. Of the four rejuvenators tested, two bio-based products enabled the maximum reuse of four cycles. Therefore, the rejuvenators used in this project are more suitable as additives to improve the physical properties of the bitumen for reuse rather than as substitutes for the binder. The datasets were further evaluated using multivariate analysis methods to construct statistical models for two use cases: In the first use case, the samples are classified by their aging condition. In the second use case, the samples are differentiated according to the rejuvenators. The models were successfully validated, providing a promising framework for the classification of unknown bitumen samples for reuse. KW - Bitumen KW - Aging KW - Rejuvenation KW - Multiple recycling KW - DSR measurements KW - Reuse KW - FTIR spectroscopy KW - Multivariate analysis methods PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-627563 DO - https://doi.org/10.1016/j.conbuildmat.2025.140734 SN - 1879-0526 VL - 472 SP - 1 EP - 16 PB - Elsevier Ltd. AN - OPUS4-62756 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Wiehle, Philipp A1 - Härder, M. A1 - Strangfeld, Christoph T1 - Moisture behaviour of earth block masonry under natural climate conditions – experimental and numerical studies N2 - The compressive stength of unstabilised earth masonry depends on the moisture content. Knowledge of the moisture content is necessary in order to be able to account for the impact of moisture on the structural design of earth block masonry. For conventional building materials it is possible to precisely forecast the component moisture according to the layered structure on the basis of hygrothermal simulations. However , it is still not clear to what degree these numerical calculations can offer valid results for earth building materials. Earth building materials have a number of special properties related to moisture storage and moisture transport that differ significantly from the physical simplifications that are a component of existing material models. The swelling and shrinking of earth materials and their organic components results in changes to the pore space, the sorption behaviour exhibits a clear hysteresis, and the experimental determination of hygrothermal parameters in continuous contact with liquid water is almost impossible. To adequately forecast the moisture content of earth block masonry under natural climate conditions, extensive investigations of the moisture behaviour of load-bearing earth block masonry have been carried out within the framework of this project. These efforts began with the performance of magnetic resonance spectroscopic tests on two load-bearing earth blocks, in order to quantify the adsorption and desorption processes at relative humidities of between 50 % and 90 % under controlled, isothermal laboratory conditions. Once this had been done, a modified test setup was used to determine the water absorption coefficient , from which the liquid transport coefficients were derived. Based on the hygrothermal parameters values that were thus determined, the model was calibrated using the WUFI software program [7]. Finally, long-term moisture measurements were conducted on an earth block masonry wall that was ex-Increasing shortages of raw materials and rising energy prices are resulting in continuous growth in the demand for earth construction. In comparison to conventional building materials, earth building materials offer three significant advantages that have become even more important in light of the energy crisis in 2021 and the associated increase in the price of building supplies by approx. 40 percent [1]. Firstly, water solubility makes it possible to fully separate and recover all of the material components, and in particular the sand component. Secondly, energy-intensive firing processes, such as those required for cement production or brick manufacture, are eliminated. And thirdly, earth is a local raw material that is available in large quantities [1]. However, the load-bearing capacity of earth building materials is very much dependent on the moisture content. An increase in the relative humidity results in a reduction in the clay mineral cohesion , and this in turn results in a decline in both the compressive strength and the modulus of elasticity. In this regard, the mechanical properties of earth block masonry change in inverse proportion to the relative humidity. In other words, with every percentage point increase in relative humidity, both the compressive strength and the modulus of elasticity decline by one percent [2] [4]. The internal walls of heated living areas are generally only subject to relatively small fluctuations in relative humidity (between 40 % and 60 %) [5], and short periods in excess of these levels (such as in bathrooms or kitchens) only lead to a significant increase in the moisture content of the uppermost layers [6]. Exterior walls, on the other hand, are subject to large seasonal fluctuations in temperate climates, with a relative humidity in excess of 90 % in winter months. However, the exterior walls of heated living areas must be insulated in accordance with the German Buildings Energy Act (GEG), and with masonry this is generally done us T2 - LEHM 2024 – 9. Internationale Fachtagung für Lehmbau CY - Weimar, Germany DA - 27.09.2024 KW - Earth stone KW - Masonry KW - Material moisture KW - Moisture monitoring KW - Hygrothermal simulations PY - 2024 SP - 1 EP - 10 AN - OPUS4-61220 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Signorini, C. A1 - Bracklow, F. A1 - Hering, Marcus A1 - Butler, M. A1 - Leicht, L. A1 - Schubert, T. A1 - Beigh, M. A. B. A1 - Beckmann, B. A1 - Curbach, M. A1 - Mechtcherine, V. T1 - Ballistic limit and damage assessment of hybrid fibre-reinforced cementitious thin composite plates under impact loading N2 - Impact resistance of reinforced concrete (RC) structures can be significantly improved by strengthening RC members with thin composite layers featuring high damage tolerance. Indeed, to limit the well-known vulnerability of cement-based materials against impact loading, the synergistic effects of short fibres and continuous textile meshes as hybrid reinforcement has been proved to be highly beneficial. This paper addresses the characterisation of novel cement-based hybrid composites through accelerated drop-weight impact tests conducted on rectangular plates at different impact energies. Two distinct matrices are assessed, with particular interest in a newly developed limestone calcined clay cement (LC3)-based formulation. Important parameters quantifying energy dissipation capability, load bearing capacity and damage are cross-checked to compute the ballistic limit and estimate the safety-relevant characteristics of the different composites at hand. Although textiles alone can improve the damage tolerance of fine concrete to some extent, the crack-bridging attitude of short, well-dispersed fibres in hybrid composites imparts a certain ductility to the cement-based matrices, allowing a greater portion of the textile to be activated and significantly reducing the amount of matrix spalling under impact. KW - Impact loading KW - Cement-based composites KW - SHCC KW - TRC KW - Sustainable binders PY - 2023 DO - https://doi.org/10.1016/j.jobe.2023.108037 VL - 80 SP - 1 EP - 21 PB - Elsevier Ltd. AN - OPUS4-58793 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Sigrüner, M. A1 - Hüsken, Götz A1 - Pirskawetz, Stephan A1 - Herz, J. A1 - Muscat, D. A1 - Strübbe, N. T1 - Pull-out behavior of polymer fibers in concrete N2 - The bond between polymer fibers and the surrounding cementitious matrix is essential for the development of concrete reinforcement. The single fiber pull-out test (SFPT) is the standard characterization technique for testing the bond strength. However, the different phases of debonding cannot be distinguished by the SFPT. This study investigates the debonding of different polymer fibers from the surrounding cementitious matrix with a modified SFPT and proposes methods to change the SFPT setup to generate more valuable information on the debonding mechanism. The SFPT was equipped with linear variable differential transformers (LVDT), digital image correlation (DIC) and acoustic emission (AE) analysis. The results demonstrate that the modified SFPT allows a better understanding of the different phases of debonding during fiber pull-out. Furthermore, bond strength values calculated by different methods reveal that the chemical bond of the investigated polymers is not different as reported by previous studies. Deformation measurements performed using LVDTs and DIC are suitable measuring techniques to characterize the debonding mechanism in SFPT. A correlation between recorded AE and debonding phases was not found. KW - Polymer Fibres KW - Concrete KW - Pull-Out Behaviour KW - Debonding Mechanism PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-582918 DO - https://doi.org/10.1002/pol.20230264 SN - 2642-4169 SP - 1 EP - 13 PB - Wiley Periodicals, LLC. AN - OPUS4-58291 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Pirskawetz, Stephan T1 - Richtlinie „Detektion von Spanndrahtbrüchen mit Schallemission“ N2 - Ein großer Teil unserer Brücken wurden in den 1950er bis 1970er Jahren als Spannbetonbrücken gebaut. Mit der damals noch relativ jungen Technologie entstanden elegante, teilweise gewagte Bauwerke mit großen Spannweiten, welche die Vorteile der Materialien Stahl und Beton geschickt kombinieren. Die Standsicherheit einiger dieser Brücken ist heute gefährdet. Die Ursachen liegen in der enorm gewachsenen Belastung durch Schwerverkehr, teilweise ungenügender Wartung und in konstruktiven und Materialschwächen, die der mangelnden Erfahrung mit der Technologie in der Bauzeit geschuldet sind. Ein neuralgischer Punkt der Bauwerke sind die in den Beton integrierten Spannglieder. Infolge von Korrosion und Ermüdung können Elemente der Spannglieder reißen, wodurch die für das Tragwerk notwendige Spannung und somit die Tragfähigkeit reduziert werden. Nicht bei allen Brücken kündigen sichtbare Risse im Beton oder auffällige Verformungen den Tragfähigkeitsverlust bzw. das finale Versagen rechtzeitig an. Die Schallemissionsanalyse ist die derzeit einzige Methode, das Reißen einzelner Spannstähle zuverlässig und mit wirtschaftlich vertretbarem Aufwand zu detektieren. Trotzdem es schon einige Spannbetonbauwerke gibt, die mit Schallemissionsanalyse überwacht werden, ist das Verfahren noch wenig bekannt. Außerdem fehlen technische Richtlinien, was die Ausschreibung und Vergabe von entsprechenden Aufträgen und die Bewertung der Angebote sehr erschwert. Um sowohl Baulastträger als auch Dienstleistungsanbieter in den Vergabeverfahren und im Betrieb der Monitoringsysteme zu unterstützen, hat sich eine Gruppe von Experten aus den Bereichen Bauingenieurwesen und Schallemission zum Entwurf einer Richtlinie „Detektion von Spanndrahtbrüchen mit Schallemission“ zusammengefunden. Mit diesem Beitrag wird die Richtlinie vorgestellt, deren Bearbeitung bis zur SCHALL 23 abgeschlossen sein soll. T2 - SCHALL 23 Entwicklung und Anwendung der Schallemissionsanalyse und Zustandsüberwachung mit geführten Wellen CY - Wetzlar, Germany DA - 21.03.2023 KW - Schallemission KW - Spannbeton KW - Brücke KW - Spannstahlbruch PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-573904 SP - 1 EP - 4 PB - DGZfP CY - Berlin AN - OPUS4-57390 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Agasty, Amit A1 - Hering, Marcus T1 - Eine Machbarkeitsstudie zur Skalierung von Sprengversuchen an Stahlbetonbauteilen N2 - Sprengversuche sind erforderlich, um Explosionsereignisse auf Grund von Unfällen oder Anschlägen zu untersuchen und um das Schutzniveau für Menschen und Anlagen in kritischen Infrastrukturen zu bewerten. Die Durchführung von Feldversuchen in großem Maßstab für komplexe Szenarien ist sehr ressourcenintensiv. Verlässliche Experimente im kleinen Maßstab sind eine vielversprechende Alternative. Die Skalierungsgesetze für die Bemessung von Stahlbetonkonstruktionen unter Explosionsbelastung sind jedoch nicht hinreichend etabliert. Die Forschungsarbeit fokussiert sich auf Stahlbetonstrukturen, die für die Standardisierung von skalierten Sprengversuchen in Frage kommen. Im Rahmen der Machbarkeitsstudie wurden auf dem TTS-Gelände Sprengversuche an Probekörpern unterschiedlicher Größe durchgeführt. Dabei wurden verschiedene horizontal gelagerte Stahlbetonplatten getestet und unterschiedlichen Explosionsbelastungen ausgesetzt. Die Sprengversuche umfassten verschiedene Messtechniken zur Quantifizierung der Explosionslast sowie des Verhaltens der Stahlbetonplatten. Die Explosionslast wurde mit bündig eingebauten piezoelektrischen Druckmessern gemessen, während Beschleunigungssensoren und flächig applizierte verteilte faseroptische Sensorik verwendet wurden, um das dynamische Verhalten der Platte unter Explosionsbelastung zu charakterisieren. Darüber hinaus wurden Schädigungsmerkmale ebenfalls mit verteilter faseroptischer Sensorik ermittelt. Die Anwendung solcher Messtechniken sowie die Nutzung verschiedener numerischer Softwaretools bieten die Möglichkeit die Skalierungsgesetze zu verifizieren bzw. anzupassen. T2 - BBK - Fachkongress Forschung für den Bevölkerungsschutz 2025 CY - Bonn, Germany DA - 05.02.2025 KW - Sprengversuch KW - Skalierung KW - Faseroptik PY - 2025 AN - OPUS4-62509 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Lehmann, F. A1 - Hille, Falk T1 - Dauerüberwachung von Ingenieurbauwerken - Das neue Merkblatt B 09 der DGZfP T1 - Permanent monitoring of engineering structures The new leaflet B 09 of the DGZFP N2 - Messtechnische Systeme zur Dauerüberwachung von Bauwerken ermöglichen Einblicke in deren reale Trag- und Verformungsverhalten. Die Planung und technische Umsetzung solcher Maßnahmen erfordern für die erfolgreiche Erfüllung der Aufgabenstellungen eine hohe Fachkompetenz, sowohl auf der planerischen Seite, als auch für die fachliche Bewertung von angebotenen Monitoringlösungen. Als Hilfestellung dafür wurde von der Deutschen Gesellschaft für Zerstörungsfreie Prüfung (DGZfP) das Merkblatt „Dauerüberwachung von Ingenieurbauwerken“ erarbeitet, welches nun verfügbar ist. In diesem Beitrag werden die Inhalte des neuen Merkblatts vorgestellt und dieses in die vorhandene Literatur eingeordnet. KW - Structural Health Monitoring KW - Brücken KW - Windenergieanlagen KW - Merkblatt KW - Bauwerksüberwachung KW - Richtlinie PY - 2023 DO - https://doi.org/10.1002/best.202200122 VL - 118 IS - 4 SP - 275 EP - 280 PB - Ernst & Sohn AN - OPUS4-57302 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schubert, T. A1 - Bracklow, F. A1 - Unger, N. A1 - Hering, Marcus A1 - Beckmann, B. T1 - Impact Tests on Reinforced Concrete Slabs – Variation in Results and Residual Load Bearing Capacity due to Hard Impact N2 - Structures such as concrete slabs and concrete barriers of critical infrastructure facilities must be able to withstand impact events or severe accidents. In particular, the structural safety of the confinements of nuclear power plants against a possible aircraft impact is essential to ensure the safety of inhabitants and environment. This article presents research results of hard impact on reinforced concrete slabs, which have been carried out at the Institute of Concrete Structures (IMB) at TUD Dresden University of Technology Technische Universität (TU Dresden). A specially designed drop tower is available for this purpose on the premises of the Otto Mohr Laboratory of TU Dresden. In the framework of a research project many reinforced concrete slabs of dimension 1.5 x 1.5 x 0.2 m³ were tested by hard impact. The investigation on some already carried out impact tests on reinforced concrete slabs intend to show the range of deviation of impact tests. In particular, the possible standard deviations that should be regarded in impact tests are estimated for the applied test setup. Furthermore, the residual structural capacity of an undamaged and damaged reinforced concrete slab has been investigated. T2 - Conference: 27th International Conference on Structural Mechanics in Reactor Technology (SMiRT) CY - Yokohama, Japan DA - 04.03.2024 KW - Reinforced Concrete KW - Drop Tower KW - Hard Impact PY - 2024 SP - 1 EP - 10 PB - IASMiRT CY - Yokohama, Japan AN - OPUS4-61915 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Reyher, Boris A1 - Stelzner, Ludwig A1 - Hothan, Sascha A1 - Hückler, Alex A1 - Pistol, Klaus A1 - Madlener, Simon A1 - Schlaich, Mike T1 - Ein Supermarkt aus Infraleichtbeton: Nachweisführung bei einer Außenwand mit Brandwandanforderungen T1 - A supermarket made of infra-lightweight concrete- Proof of stability for a fire wall N2 - Infraleichtbeton (ILC) ist eine spezielle Form von Leichtbeton, der durch seine niedrige Rohdichte im Vergleich zu herkömmlichem Beton eine verbesserte Wärmedämmeigenschaft aufweist. Infraleichtbeton ermöglicht die monolithische einschichtige Konstruktion von Bauteilen der Gebäudehülle ohne additive Wärmedämmung und Fassadenbekleidung. Dadurch wird die Baukonstruktion gegenüber herkömmlich gedämmten Betonbauteilen erheblich vereinfacht und die Recyclingfähigkeit deutlich verbessert. Zudem weisen Bauteile aus Infraleichtbeton eine günstigere CO2‐Bilanz auf als Außenwandkonstruktionen in konventioneller Bauweise wie z. B. Wärmedämmverbundsysteme. Nach etwa 15 Jahren Forschung und diversen Bauvorhaben im Wohn‐ und Bildungssektor konnte nun ein erster Einzelhandelsmarkt mit Außenwänden aus Infraleichtbeton realisiert werden. Im Rahmen dieses Bauvorhabens wurde erfolgreich eine vorhabenbezogene Bauartgenehmigung (vBG) auf der Grundlage eines Brandversuchs und eines auf Berechnungen basierenden Übertragungskonzepts für eine Brandwand aus ILC erwirkt. Der Beitrag stellt das Übertragungskonzept sowie ein für die vorliegende besondere Bauweise der Brandwand entwickeltes vereinfachtes Berechnungsverfahren zum Nachweis der Standsicherheit im Brandfall vor. N2 - htweight concrete (ILC) is a special form of light-weight concrete which, due to its low density, possesses improved thermal insulation properties in comparison to normal concrete. ILC facilitates the construction of monolithic, single-layer building skins without any added thermal insulation or facade cladding. This way, the building components are effectively simplified in comparison to conventionally insulated concrete members and the recyclability is significantly improved. In addition to that, structural elements made of ILC have a reduced CO2 footprint in comparison to conventional composite elements of the building envelope. After 15 years of research and several completed construction projects in the housing and education sector, a commercial retail building has been realized. For this project, an individual approval for a firewall built out of ILC was obtained based on a fire test in combination with a transfer concept based on calculations. This article demonstrates the transfer concept as well as a simplified structural analysis concept for the proof of stability developed for the special application of a firewall. KW - Infraleichtbeton KW - Brandschutz KW - Brandwand KW - Hallenkonstruktion KW - Bauen im Bestand PY - 2024 DO - https://doi.org/10.1002/best.202400016 SN - 0005-9900 VL - 119 IS - 9 SP - 658 EP - 666 PB - Wiley AN - OPUS4-61409 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Grunewald, Thomas A1 - Grätz, Rainer A1 - Kühne, Hans-Carsten T1 - Werkzeuge zur Verwendung in explosionsgefährdeten Bereichen - Erkenntnisse zur Zündwahrscheinlichkeit von Edelstahl und NE-Metallen gegen Baustahl und Estrichbeton in Wasserstoff und Acetylen N2 - Üblicherweise werden Werkzeuge für den industriellen Einsatz aus hochlegierten Chromstählen hergestellt. Für den Einsatz in explosionsgefährdeten Bereichen werden oft Werkzeuge aus speziellen Nichteisen-Metalllegierungen (NE-Metall) verwendet. Für diese sogenannten funkenarmen Werkstoffe und deren mögliche Schlagpartner gibt es bisher keine umfassenden Untersuchungen mit Aussagen zur Zündwahrscheinlichkeit. Die TRGS 723, Abschn. 5.15, fordert den Nachweis der Funkenfreiheit der verwendeten Werkstoffpaarung. Jedoch sind Werkzeuge keine Geräte oder Schutzsysteme im Sinne der Richtlinie 2014/34/EU. Deshalb ist es nicht möglich, Werkzeuge in Übereinstimmung mit dieser Richtlinie zu zertifizieren. Der Nachweis der Erfüllung dieser Anforderungen ist durch Zertifizierungen im sogenannten "gesetzlich nicht geregelten" Bereich möglich. Die BAM bietet diese Zertifizierung für "Funkenarme Werkzeuge" im Rahmen ihres Zertifizierungsprogrammes an. Die bisherigen Ergebnisse der hier vorgestellten Untersuchung haben gezeigt, dass es keine funkenfreien, metallischen Werkzeuge (non-sparking Tools) gibt. Entscheidend ist im Hinblick auf die TRGS 723, ob zündfähige Funken entstehen oder nicht. Es ist immer die Frage, worauf die Werkzeuge im praktischen Anwendungsfall schlagen oder fallen gelassen werden können, d.h. aus welchem Material der mögliche Schlagpartner besteht. Dies können metallische Schlagpartner, aber auch Betonoberflächen sein. Unterschiedliche Kombinationen von Werkstoffen ergeben bei Schlagbeanspruchung im explosionsgefährdeten Bereich jeweils unterschiedliche Zündwahrscheinlichkeiten. Aber auch die Höhe der beim Einsatz der Werkzeuge möglichen kinetischen Schlagenergie und der Brenngas/Luft-Atmosphäre im betreffenden explosionsgefährdeten Bereich sind wichtige Einflussgrößen. KW - Mechanisch erzeugte Funken KW - Nichtelektrische Funken KW - Schlagfunken KW - Schleiffunken KW - Reibfunken KW - Funkenarmes Werkzeug KW - Funkenfreies Werkzeug KW - Nichtelektrischer Explosionsschutz KW - Non sparking tools PY - 2021 DO - https://doi.org/10.37544/2191-0073-2021-11-12-33 SN - 2191-0073 VL - 11 IS - 11-12 SP - 33 EP - 37 PB - VDI Fachmedien CY - Düsseldorf AN - OPUS4-53936 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Herrmann, Ralf A1 - Hille, Falk A1 - Munsch, Sarah Mandy A1 - Telong, Melissa A1 - Unger, Jörg F. A1 - Andrés Arcones, Daniel A1 - Pirskawetz, Stephan T1 - 63. DAfStb-Forschungskolloquium in der BAM - Themenblock 4: Digitalisierung im Bauwesen N2 - Die Digitalisierung hat sich in vielen Bereichen des Bauwesens durchgesetzt. So sind Planung und Entwurf selbst kleinerer Bauvorhaben heute vollständig digitalisiert. Auch das Monitoring von Bestandsbauwerken ist ohne digitale Datenerfassung, -verarbeitung und -speicherung nicht denkbar. Trotzdem sind Fragen hinsichtlich der strukturierten Speicherung und künftigen Nutzung von Daten noch offen. Einige Aspekte der Digitalisierung wurden im Rahmen des 63. DAfStb-Forschungskolloquiums (Tagungsband: DOI 10.26272/opus4-61338) in Vorträgen und Veröffentlichungen aufgegriffen und werden im Folgenden zusammengefasst. T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM Green Intelligent Building CY - Berlin, Germany DA - 16.10.2024 KW - Digitalisierung KW - Infrastruktur KW - Structural Health Monitoring KW - Digitaler Zwilling PY - 2025 SN - 0005-9846 VL - 75 IS - 4 SP - 136 EP - 138 PB - concrete content UG CY - Schermbeck AN - OPUS4-63070 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hüsken, Götz A1 - Strangfeld, Christoph A1 - Robens-Radermacher, Annika A1 - von Werder, Julia A1 - Weigel, Sandra A1 - Mezhov, Alexander T1 - 63. DAfStb-Forschungskolloquium in der BAM - Themenblock 3: Innovative Technologien N2 - Innovationen sind der Treiber des technologischen Fortschritts. Durch die Anwendung innovativer Technologien, Produktionsverfahren und neuer Materialien können Effizienzsteigerungen erzielt werden, die sowohl zu einer Kosten- als auch Materialreduzierung führen können. Gerade vor dem Hintergrund einer nachhaltigen Entwicklung sind Innovationen der Schlüssel zu einem verantwortungsvollen Umgang mit Ressourcen und Rohstoffen. Im Rahmen des 63. DAfStb-Forschungskolloquiums (Tagungsband: DOI 10.26272/opus4-61338) an der BAM wurden innovative Ansätze im Bereich effizienter Fertigungstechnologien und neuer Materialien vorgestellt, die nachfolgend kurz zusammengefasst werden. T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM Green Intelligent Building CY - Berlin, Germany DA - 16.10.2024 KW - Additive Fertigung KW - Biorezeptive Oberflächen KW - Biopolymere PY - 2025 SN - 0005-9846 VL - 75 IS - 4 SP - 134 EP - 135 PB - concrete content UG CY - Schermbeck AN - OPUS4-63069 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Otto, Peter A1 - Lorenzis, L. A1 - Unger, Jörg F. T1 - Explicit dynamics in impact simulation using a NURBS contact interface N2 - In this paper, the impact problem and the subsequent wave propagation are considered. For the contact discretization an intermediate NURBS layer is added between the contacting finite element bodies, which allows a smooth contact formulation and efficient element‐based integration. The impact event is ill‐posed and requires a regularization to avoid propagating stress oscillations. A nonlinear mesh dependent penalty regularization is used, where the stiffness of the penalty regularization increases upon mesh refinement. Explicit time integration methods are well suited for wave propagation problems, but are efficient only for diagonal mass matrices. Using a spectral element discretization and the coupled FE‐NURBS approach the bulk part of the mass matrix is diagonal. KW - Impact simulation KW - Explicit dynamics KW - Isogeometric analysis KW - Spectral elements KW - Mortar method PY - 2019 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-494947 DO - https://doi.org/10.1002/nme.6264 SP - 1 EP - 21 PB - Wiley Online Libary AN - OPUS4-49494 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Coelho Lima, Isabela A1 - Robens-Radermacher, Annika A1 - Titscher, Thomas A1 - Kadoke, Daniel A1 - Koutsourelakis, P.-S. A1 - Unger, Jörg F. T1 - Bayesian inference for random field parameters with a goal-oriented quality control of the PGD forwardmodel's accuracy N2 - Numerical models built as virtual-twins of a real structure (digital-twins) are considered the future ofmonitoring systems. Their setup requires the estimation of unknown parameters, which are not directly measurable. Stochastic model identification is then essential, which can be computationally costly and even unfeasible when it comes to real applications. Efficient surrogate models, such as reduced-order method, can be used to overcome this limitation and provide real time model identification. Since their numerical accuracy influences the identification process, the optimal surrogate not only has to be computationally efficient, but also accurate with respect to the identified parameters. This work aims at automatically controlling the Proper Generalized Decomposition (PGD) surrogate’s numerical accuracy for parameter identification. For this purpose, a sequence of Bayesian model identification problems, in which the surrogate’s accuracy is iteratively increased, is solved with a variational Bayesian inference procedure. The effect of the numerical accuracy on the resulting posteriors probability density functions is analyzed through two metrics, the Bayes Factor (BF) and a criterion based on the Kullback-Leibler (KL) divergence. The approach is demonstrated by a simple test example and by two structural problems. The latter aims to identify spatially distributed damage, modeled with a PGD surrogate extended for log-normal random fields, in two different structures: a truss with synthetic data and a small, reinforced bridge with real measurement data. For all examples, the evolution of the KL-based and BF criteria for increased accuracy is shown and their convergence indicates when model refinement no longer affects the identification results. KW - Variational inference KW - Proper generalized decomposition KW - Goal-oriented KW - Digital twin KW - Random field PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-555755 DO - https://doi.org/10.1007/s00466-022-02214-6 SN - 1432-0924 SP - 1 EP - 22 PB - Springer CY - Berlin AN - OPUS4-55575 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Strangfeld, Christoph A1 - Schönsee, Eric A1 - Jeyifous, Olubunmi Anthony A1 - Mezhov, Alexander A1 - Hüsken, Götz T1 - Introduction of a monitoring system for Bingham fluids in additive manufacturing with concrete N2 - Freeform additive manufacturing of concrete structures is a rising technology in civil engineering with several fascinating advantages. Nonetheless, to ensure reliability and structural integrity, standards and quality control are required in the future to bring this technology into the market. As the concrete is manufactured continuously, continuous quality control of the printing process is also required, i.e. comprehensive process monitoring. At BAM, a test rig will be installed, enabling the printing of concrete structures with a maximum size of 2 m x 1 m x 1 m (l x w x h). Here, process monitoring is the focus of the test rig. In this study, we show the results of the first pump tests, including the measurement of several parameters such as temperature and pressure along the supply system, i.e. from the concrete pump to the printer head. T2 - NDT-CE 2022 CY - Zurich, Switzerland DA - 16.08.2022 KW - Additive manufacturing of concrete KW - Process monitoring KW - Non-destructive testing KW - Bingham fluid PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-556367 SP - 1 EP - 12 AN - OPUS4-55636 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Pohl, Christoph A1 - Smilauer, V. A1 - Unger, Jörg F. T1 - A three-phase transport model for high-temperature concrete simulations validated with X-ray CT data N2 - Concrete exposure to high temperatures induces thermo-hygral phenomena, causing water phase changes, buildup of pore pressure and vulnerability to spalling. In order to predict these phenomena under various conditions, a three-phase transport model is proposed. The model is validated on X-ray CT data up to 320 ◦C, showing good agreement of the temperature profiles and moisture changes. A dehydration description, traditionally derived from thermogravimetric analysis, was replaced by a formulation based on data from neutron radiography. In addition, treating porosity and dehydration evolution as independent processes, previous approaches do not fulfil the solid mass balance. As a consequence, a new formulation is proposed that introduces the porosity as an independent variable, ensuring the latter condition. KW - Concrete KW - Porous media KW - Spalling KW - Dehydration KW - Moisture transport KW - Heat transfer KW - Pore pressure KW - Porosity KW - Finite elements PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-532840 UR - https://doi.org/10.5281/zenodo.4890635 DO - https://doi.org/10.3390/ma14175047 SN - 1996-1944 VL - 14 IS - 17 SP - 1 EP - 21 PB - MDPI CY - Basel AN - OPUS4-53284 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Sittner, Jonathan A1 - Götze, Jens A1 - Müller, Axel A1 - Renno, Axel D. A1 - Ziegenrücker, René A1 - Pan, Yuanming T1 - Trace element analysis and luminescence behavior of quartz in pegmatites of the Tørdal Region, Norway N2 - This publication presents a study on the mineral chemistry and luminescence properties of quartz samples from pegmatites of the Tørdal region in Norway. A total of 12 samples were analyzed using Secondary Ion Mass Spectrometry (SIMS), Electron Paramagnetic Resonance Spectroscopy (EPR), and Cathodoluminescence (CL) to gain insights into their trace element concentration and distribution as well as their luminescence behavior. The samples are characterized by different Cl emissions at 450 nm, 500 nm 650 nm and an additional shoulder at 390 nm, which is only partially visible due to the absorption of the glass optics. Of these luminescence bands, the 500 nm band is the most dominant in most samples and it is characterized by an initial blue-green luminescence, which is not stable under electron irradiation. Moreover, it is characterized by a heterogeneous distribution within the samples. This luminescence can be mostly assigned to [AlO4/M+]0 defects, with charge compensation mostly achieved by Li+. Analyses by EPR spectroscopy prove the dominance of structurally bound Al, Li, and Ti ions in the investigated samples. Further analyses using SIMS mapping demonstrate that Na and K are mainly bound to micro fractures or inclusions, suggesting a limited role in the compensation of the luminescence centers. Additionally, the SIMS mappings show that some samples contain Al-rich clusters of 10 to 20 µm in diameter, whereas other trace elements are characterized by a homogeneous distribution. These clusters correspond to bright luminescence areas in size and shape and could potentially indicate H+ compensated [AlO4/M+]0 defects. KW - Quartz KW - Trace elements KW - SIMS KW - Cathodoluminescence KW - EPR KW - Tørdal KW - Pegmatite PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-612529 DO - https://doi.org/10.1016/j.chemgeo.2024.122427 VL - 670 SP - 1 EP - 15 PB - Elsevier BV AN - OPUS4-61252 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hüsken, Götz A1 - Jeyifous, Olubunmi Anthony A1 - Schönsee, Eric A1 - Strangfeld, Christoph T1 - An assessment of the repeatability of 3D printed concrete structures N2 - Additive manufacturing of concrete structures, also known as 3D concrete printing, is a technology that received a lot of attention over the past decade due to its financial an ecological advantage as sustainable construction technology. Although several techniques and approaches demonstrate these advantages, quality control during printing is highly challenging and rarely applied and harmonized standards are not existing. Due to the continuous mixing process used in 3D concrete printing, it is impossible to exclude variations in the dry mixture or water content, and a single test sample is insufficient to be representative for the whole structure. A defect in one layer during the printing can affect the entire integrity of the whole structure. This study shows the results of an arch designed as framework structure that was printed multiple times under the same boundary conditions using an extrusion-based 3D concrete printer. Each arch was tested for its mechanical strength and load bearing behavior. The results of the mechanical testing of the printed arches are compared with material data obtained by classical tests and discussed regarding their statistical significance. T2 - Digital Concrete 2024 CY - Munich, Germany DA - 04.09.2024 KW - 3D concrete printing KW - Repeatability KW - Monitoring KW - Process control KW - Quality control PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-611012 DO - https://doi.org/10.24355/dbbs.084-202408150641-0 SP - 1 EP - 9 PB - TU Braunschweig AN - OPUS4-61101 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - He, Yuxiang T1 - Automated workflows for concrete additive manufacturing for design, optimization and fabrication of parametrized elements N2 - 3D concrete printing is an innovative new construction technology offering the potential to enable an efficient production of individual structures with less consumption of resources. The technology will mainly shape the future construction philosophy, automate the build process and help reaching the climate goals in civil engineering. From the design of a structure to the printed component, many individual steps based on different software are required which must be repeated for each new or changed structure. First, the geometry of the structure is created in a CAD program. Second, the print path is defined in a slicer software creating the machine code for the printer (G-Code). Finally, the structure can be printed. Furthermore, a numerical model of the printed structure is necessary for process optimization and control. In that way the number of test prints can be reduced, costs can be saved, and the component behavior can be predicted. For those purposes, an automated workflow allowing to run all steps or individual steps without interacting with each individual software program is required. Furthermore, changes in parameters or the exchange of parts (using a different design or different printer) must be possible in a simple manner. In the presented work, such an automated workflow based on the example of a parametrized wall element for extrusion-based concrete printing is developed. The investigated wall structure is parametrized using the global geometry parameters: height, width, thickness, radius, kind of infill structure (honey-comb, zig-zag) and number of repeated infills. All above mentioned steps are implemented via python interfaces using pydoit as workflow tool. General interfaces with prescribed input and output files are defined allowing adaptations for different software and tools. The described workflow is tested by performing a test series investigating the influence of the in-fill structure on the mechanical properties of the test walls. T2 - RILEM spring convention & conference on advanced construction materials and processes for a carbon neutral society 2024 CY - Milan, Italy DA - 07.04.2024 KW - 3D concrete printing KW - Design KW - G-Code KW - Simulation KW - Automatization PY - 2024 UR - https://www.rilem.net/agenda/rilem-spring-convention-conference-on-advanced-construction-materials-and-processes-for-a-carbon-neutral-society-1530 AN - OPUS4-59909 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Munsch, Sarah Mandy T1 - Ermittlung der Porosität von Sandsteinen - Vergleich von Quecksilberporosimetrie, Tauchwägung und NMR N2 - Die Porosität sowie die Porengrößenverteilung (PSD) eines Baustoffs sind wichtige petrophysikalische Eigenschaften, die Transportprozesse im Material beeinflussen und im direkten Zusammenhang mit der Schadensanfälligkeit stehen (Frost-Tau-Schäden, Schäden durch Salzeinträge und sauren Regen). Verfahren zur Ermittlung der Porosität stellen die Quecksilberporosimetrie (MIP), das Prinzip der Tauchwägung nach Archimedes (triple weighing method, TWM) und die Nuklear Magnetische Resonanz (NMR) dar. Das Hauptziel dieser Arbeit ist der Vergleich der drei Methoden für die Porositätsbestimmung. Als Untersuchungsmaterial wurde Sandstein gewählt. Als Baustoff wird Sandstein trotz einer teilweise geringen Festigkeit, aber aufgrund seiner Farbvielfalt häufig für Kulturbauten, Gehwegmaterial und Fassaden eingesetzt. Sandsteine weisen zudem meist eine hohe effektive Porosität (bis zu ca. 30 %) und teilweise breite Porengrößenspektren auf, wodurch Feuchte- und Ioneneinträge begünstigt werden und zu z. B. langfristigen Verfärbungen an Sandsteinfassaden führen können. Im Rahmen dieser Arbeit werden die Porositäten von 10 verschiedenen Sandsteinen aus Deutschland und Tschechien bestimmt. Für die Untersuchungen mittels TWM und NMR wurden für jede Sandsteinart zwei zylinderförmige Proben unter Unterdruck mit Leitungswasser aufgesättigt. Beim Vergleich der Verfahren liegt der Fokus insbesondere auf NMR und der verwendeten Gerätetechnik, die mit einer minimalen Echozeit von 50 µs ein Wasserstoffsignal in Sandsteinen aus bis zu ca. 2 nm kleine Poren erfassen kann. Darüber hinaus wird das Auflösungsvermögen von MIP und NMR bezüglich der Poren- bzw. Poreneingangsgrößen diskutiert. Für den Vergleich von NMR und MIP werden an ausgewählten Sandsteinproben ebenfalls die zusätzlich ermittelten PSD in Korrelation zueinander gebracht. Erste Ergebnisse zeigen eine gute Korrelation von NMR- und TWM-Daten, aber teilweise starke Abweichungen zu den mit MIP bestimmten Porositäten. Ergebnisse zu den PSD zeigen teilweise nahezu identische Kurvenverläufe. Jedoch ist die Abschätzung des Umrechnungsfaktors für die NMR-Daten ohne Hinzuziehen von zusätzlichen Referenzverfahren wie Röntgen-Computer-Tomographie oder Spektral Induzierte Polarisation teilweise sehr schwierig. T2 - Bauwerksdiagnose CY - Berlin, Germany DA - 13.02.2020 KW - NMR KW - Porosität KW - Sandsteine KW - Quecksilberporosimetrie KW - Tauchwägung PY - 2020 N1 - Geburtsname von Munsch, Sarah Mandy: Nagel, S. M. - Birth name of Munsch, Sarah Mandy: Nagel, S. M. AN - OPUS4-50405 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Rogge, Andreas A1 - Meng, Birgit A1 - Kühne, Hans-Carsten T1 - 63. DAfStb-Forschungskolloquium in der BAM - Green Intelligent Building N2 - Das jährlich im Herbst an wechselnden Forschungsstandorten stattfindende DAfStb-Forschungskolloquium wurde im Jahr 2024 von der BAM Bundesanstalt für Materialforschung und -prüfung in Berlin ausgerichtet. Unter der Überschrift „Green Intelligent Building“ referierten rd. 35 Vortragende in fünf Sitzungen unterschiedlicher Thematik über verschiedene betonbezogene Forschungsschwerpunkte in der BAM. Anhand der überwiegend von Doktoranden und Post-Docs dargebotenen Vorträge konnten sich die Teilnehmerinnen und Teilnehmer ein aktuelles Bild von der Qualität der wissenschaftlichen Arbeit und der hervorragenden Forschungsmöglichkeiten in der BAM machen. Durch die Vernetzung unterschiedlich ausgerichteter Fachbereiche innerhalb der BAM werden Synergie-Effekte genutzt. Analytische, baustoffliche, konstruktive, umweltorientierte und auf die Verfahrensentwicklung ausgerichtete Bereiche der BAM forschen gemeinsam zum Thema Stahlbetonbau. Es folgen ausführliche Zusammenfassungen der Tagungsinhalte. T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM Green Intelligent Building CY - Berlin, Germany DA - 16.10.2024 KW - Bauteile KW - Bauwerke KW - Beton KW - Chemie der Bindemittel KW - Digitalisierung im Bauwesen KW - Green Intelligent Building KW - Innovative Technologien KW - Klimafreundliche Bindemittel KW - Ressourcenschonung PY - 2025 SN - 0005-9846 VL - 75 IS - 4 SP - 128 EP - 129 PB - concrete content UG CY - Schermbeck AN - OPUS4-63109 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Jafari, Abbas T1 - Bayesian identification of constitutive laws using full-field displacements N2 - Mechanical structures are widely analysed by means of numerical simulators developed based on physical laws. In the context of structural mechanics, while the formulations of both kinetics and kinematics are transparently established in accordance with Newton’s laws and the compatibility condition of deformation, the constitutive relation often suffers from a considerable amount of uncertainties. Such uncertainties are mainly rooted in insufficient physics and imprecise assumptions and simplifications. In recent decades, Bayesian techniques have been utilized for coping with these uncertainties and for quantifying the level of confidence that may be attributed to the inferred model. Among various approaches, some of which are reviewed in [1], this work focuses on the parameter identification of a candidate parameterized physics-based constitutive model, on the basis of full-field measurements of displacements. These measurements are assumed to be obtained in the form of Digital Image Correlation (DIC) measurements, complemented with external force measurements at the structural level aggregated over certain sub-boundaries. The principal idea is to minimize a suitable objective function that measures the discrepancy between the parameterized model’s response and the measured quantities. This objective function is formulated in terms of the internal forces and the measured aggregated forces, and the associated Bayesian inverse problem is introduced. A variational Bayesian scheme, originally proposed in [2], is employed to compute the unknown posteriors considered as multivariate normal distributions. We verify our framework on two synthetic examples described by a gradient damage model [3] and an elastic law, with the former reflecting a path-dependent nonlinear constitutive law. The first example illustrates an application of the proposed procedure to cracked structures. In the second example, a regularizer, in terms of admissible stresses, is further incorporated to the identification procedure, offering robustness against contamination of measurements with noise. T2 - The 9th European Congress on Computational Methods in Applied Sciences and Engineering CY - Lisbon, Portugal DA - 03.06.2024 KW - Bayesian inference KW - Constitutive law KW - Full-field measurements PY - 2024 AN - OPUS4-62243 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rogge, Andreas T1 - Future Challenges in Construction engineering N2 - Productivity and sustainability are key factors for the technical development of the construction sector during the next decades. Only a corresponding, goal-oriented and efficient combination of specifically developed construction materials and techniques based on innovative digital technologies and ideas will contribute to the huge societal challenges of the future. On a material level, sustainability in concrete production stands for the use of alternative binders, aggregates and reinforcing fibres in combination with bio-based additives to produce robust mixtures with a minimized CO2-footprint. On a constructional level, the focus will be on reducing manpower on site by automated techniques like additive manufacturing and by an increased use of prefabricated elements up to modular room cells, accompanied by innovative methods for the re-use of constructional elements, reduction of supplementary constructions and digitally optimized site logistics. This presentation will discuss recent developments in these fields, as well as upcoming ideas. T2 - CoMS 2021 Construction Materials for a Sustainable Future CY - Online meeting DA - 20.04.2021 KW - Sustainability KW - Productivity KW - Prefabrication PY - 2021 AN - OPUS4-52482 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Jeyifous, Olubunmi Anthony T1 - Correlation of continuously measured in-line process parameters and extruded geometry in 3D concrete printing experiments N2 - Additive manufacturing of concrete structures is a novel and emerging tech-nology. Free contouring in civil engineering, which allows for entirely new designs, is a significant advantage. Although several techniques and ap-proaches demonstrate these advantages, quality control during printing is highly challenging and rarely applied. Due to the continuous mixing process used in 3D concrete printing, it is impossible to exclude variations in the dry mixture or water content, and a single test sample is insufficient to represent the whole structure. A defect in one layer during printing can affect the in-tegrity of the entire structure. Therefore, continuous and real-time process monitoring is required to record and document the printing process. At the Bundesanstalt für Materialforschung und -prüfung (BAM), a test rig for 3D concrete printing was developed to monitor the properties during the printing process. This study investigates the relationship between geometric accuracy and process parameters (pressure, pump torque, print speed, layer height, water content) in extrusion-based 3D concrete printing. Using a high-precision laser scanner, the geometric measurements of printed concrete ele-ments are evaluated in real-time. The concrete elements are printed under controlled conditions with varied process parameters. Preliminary findings indicate a significant correlation between process variables and geometric ac-curacy. T2 - Fourth RILEM International Conference on Concrete and Digital Fabrication CY - Munich, Germany DA - 04.09.2024 KW - 3D concrete printing KW - Geometric accuracy KW - Process monitoring KW - Quality control PY - 2024 DO - https://doi.org/https://doi.org/10.1007/978-3-031-70031-6_15 AN - OPUS4-61532 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Herrmann, Ralf A1 - Moortgat-Pick, A. A1 - Marx, S. ED - Helmerich, Rosemarie ED - Ilki, A. ED - Motavalli, M. T1 - Vibration Analysis of Structures using a Drone (UAV) based Mobile Sensing Platform N2 - The identification of the dynamic behavior of structures, like bridges and towers, is relevant to address multiple issues. In many cases the dynamic parameters should be acquired only once or at a frequency that doesn’t justify the installation of distinct vibration sensors for a long-term monitoring. To identify modal frequencies of a structure, a drone based mobile sensing platform has been implemented. This sensing platform measures the relative displacement be-tween the structure and the drone, which also shows a strong dynamic behavior under wind tur-bulences. By regarding the dynamic model of the drone and additional measurements at the dis-tance sensor the absolute movement of the structure can be estimated based on the measured relative distance. This time domain data is a suitable input for various operational modal analysis algorithms. The system has been used to identify the dynamic properties of test and real structure, like a 1.5 MW wind turbine tower. T2 - 5th International Conference on Smart Monitoring, Assessment and Rehabilitation of Civil Structures (SMAR 2019) CY - Potsdam, Germany DA - 27.08.2019 KW - Modal Analysis KW - Drone KW - Vibration KW - Wind Turbines KW - Bridges PY - 2019 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-492045 UR - http://data.smar-conferences.org/downloads/SMAR_2019_Proceedings.zip SN - 978-3-947971-07-7 SP - We.4.C.3 EP - 8 PB - German Society for Non-Destructive Testing (DGZfP e.V.) AN - OPUS4-49204 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Thiele, Marc A1 - Hille, Falk A1 - Makris, Ruben ED - Helmerich, Rosemarie ED - Ilki, A. ED - Motavalli, M. T1 - Comparison of fatigue crack detection methods for high-cyclic loaded steel structures N2 - At present, to produce renewable energy offshore wind farms play an important role. The available space combined with the more valuable wind conditions make offshore locations very attractive for wind powered energy production. In Europe a significant number of offshore wind farms already exist, especially in the North and Baltic Sea. In future this trend will continue, and further offshore wind farms will be built. The majority of offshore wind turbines are mounted on steel foundation structures. Due to the high-cyclic loading by wind and waves fatigue stress plays a substantial role regarding structural safety. Besides the consideration of fatigue within the design process, to monitor existing steel structures for potential fatigue cracks during their life time is a major topic and a challenge. For the structures of the offshore wind turbines are large and partially under water effective reliable methods for the detection of fatigue cracks are required. This contribution presents investigations on different crack detection methods applied at high-cycle fatigue tests on small-scale welded steel samples as well as on large-scale welded steel components. The tests were conducted at the BAM laboratories. For crack detection mainly three different methods were used and compared. The first method regards to the measurement of strain by conventionally strain gauges. Secondly, the crack luminescence was used as a new and effective optical method for surface monitoring. And finally, crack detection by pressure differentials of the inner and outer section of tubular steel elements was investigated. A comparison study will emphasize the advantages and disadvantages of the different methods and show which of the described methods is potentially more suitable for an application on real offshore wind structures. T2 - 5th International Conference on Smart Monitoring, Assessment and Rehabilitation of Civil Structures CY - Potsdam, Germany DA - 27.08.2019 KW - Fatigue KW - Steel structures KW - Crack detection PY - 2019 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-489433 SP - Th.2.A.1-1 EP - Th.2.A.1-8 AN - OPUS4-48943 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF ED - Weise, Frank ED - Stelzner, Ludwig ED - Dehn, F. T1 - 7th international workshop on concrete spalling due to fire exposure - Proceedings N2 - The fire-induced spalling behaviour of concretes has a huge effect on the fire resistance of concrete components. Therefore, fire performance must be taken into account in the design and dimensioning of concrete structures. The use of new types of concrete and different types of cement or binder must also be considered. Despite decades of research, the mechanisms underlying the spalling phenomenon are not yet fully understood. However, knowledge about these mechanisms is the prerequisite for predicting the spalling behaviour as accurately as possible. Experimental research from material characterisation on the micro scale up to full-sized fire tests as well as the simulation and modelling of fire-induced damage processes offer the opportunity to investigate the spalling behaviour of concrete. Thereby, a variety of influencing parameters must be regarded. Against this background, the effect of avoidance strategies can be evaluated. Since 2009, the International Workshop on Concrete Spalling due to Fire Exposure (IWCS) offers a platform to get in touch with researchers and practitioners, exchange the latest research results and newly acquired data from real fire scenarios, and discuss current developments in the field of concrete spalling. After the successful workshops in Leipzig (Germany), Delft (Netherlands), Paris (France), Borås (Sweden) and Sheffield (United Kingdom), the 7th International Workshop IWCS took place in Berlin at BAM. It provided insights into the work of two RILEM Technical Committees. Based on this, various results of screening tests and large-scale tests for the assessment of the fire-induced spalling behaviour of concretes were presented, taking into account a large number of influencing parameters. Further topics of the workshop were the analysis of the mechanisms for the spalling phenomenon as well as the modelling and simulation of the spalling processes. A large part of the workshop was devoted to the high-temperature behaviour of various types of concrete. The workshop was dedicated to Prof. Diederichs, who passed away on 20 January 2022. With his death, the spalling community lost an internationally renowned expert in the field of fire behaviour of concrete and reinforced concrete components. He played a decisive role in the design of all previous RILEM TCs on the high temperature and fire behaviour of concretes and reinforced concrete components. T2 - IWCS 2022 CY - Berlin, Germany DA - 12.10.2022 KW - High temperature behaviour of concretes KW - Concrete spalling due to fire exposure KW - Screening-tests KW - Large-scale tests KW - Mechanisms for the spalling phenomenon KW - Modelling and simulation KW - Fire behaviour of concretes PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-560798 SP - 1 EP - 257 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-56079 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Pirskawetz, Stephan A1 - Schmidt, S. T1 - Detection of wire breaks in prestressed concrete bridges by Acoustic Emission analysis N2 - problem. One reason is the sensitivity to stress corrosion cracking of the prestressing steel. Failure of prestressing wires can result in collapse of the entire structure without premature indication by transverse bending cracks or considerable deformation. The response of a structure to significant number of prestressing wire breaks was studied on a bridge in Brandenburg, Germany. Two thirds of the prestressing wires in concentrated tendons of two girders were cut before the bridge was demolished. Acoustic Emission Analysis was used to detect the wire breaks. Thus, the number of wire breaks was correlated with results of other measurement techniques, in particular strain measurements on the girders. In preparation of the measurements, the acoustic properties of the bridge were determined and the suitability of Schmidt hammer impacts as an acoustic reference source was validated. KW - Real scale test KW - Acoustic emission monitoring KW - Structural health monitoring (SHM) KW - Prestressed concrete bridge KW - Stress corrosion cracking KW - Wire break KW - Destructive testing KW - Nondestructive testing PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-573927 DO - https://doi.org/10.1016/j.dibe.2023.100151 SN - 2666-1659 VL - 14 SP - 1 EP - 10 PB - Elsevier Ltd AN - OPUS4-57392 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Klimek, André A1 - Stelzner, Ludwig A1 - Hothan, Sascha A1 - Rogge, Andreas T1 - Fire induced concrete spalling in combination with size effects N2 - The size effect has its origin in fracture mechanics and describes the formation as well as propagation of cracks in brittle and solid materials in dependence of the specimen size. However, the size effect in concrete spalling describes the damage behaviour on a macroscopic scale for different sized specimens in case of fire. Concrete spalling is a very complex and yet not fully understood phenomenon. To reduce the effort of fire tests to analyse the spalling behaviour of concrete mixtures, this study investigates the susceptibility to spalling for six different concrete mixtures and three specimen sizes. The sizes were divided in full scale slabs (1.8 m x 1.2 m x 0.3 m), intermediate scale cuboids (0.6 m x 0.6 m x 0.3 m) and small scale cylinders (Ø0.15 m x 0.3 m). For this purpose, a novel test set-up was built to test six intermediate scale or twelve small scale specimens simultaneously to ensure a similar heating regime for every specimen. All specimens were fire exposed on one side and remained unrestrained. A size effect occurred for four of the six concrete mixtures. Compared to the full scale specimens the spalling was reduced significantly for all smaller specimen sizes. Additionally, spalling did not occur for the small scale specimens. The results show that the specimen size is an essential parameter to investigate the susceptibility to spalling of a concrete mixture. For future investigations the testing conditions must be adjusted for the intermediate scale specimens to recreate the conditions of the slabs. KW - Concrete KW - Spalling KW - Size effect KW - Fire test PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-559231 DO - https://doi.org/10.1617/s11527-022-02051-2 VL - 55 IS - 8 SP - 1 EP - 14 PB - Springer AN - OPUS4-55923 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Mendler, A. A1 - Döhler, M. A1 - Hille, Falk T1 - Detecting changes in boundary conditions based on sensitivity-based statistical tests N2 - Structural health monitoring is a promising technology to automatically detect structural changes based on permanently installed sensors. Vibration-based methods that evaluate the global system response to ambient excitation are suited to diagnose changes in boundary conditions, i.e., changes in member prestress or imposed displacements. In this paper, these changes are evaluated based on sensitivity-based statistical tests, which are capable of detecting and localizing parametric structural changes. The main contribution is the analytical calculation of sensitivity vectors for changes in boundary conditions (i.e., changes in prestress or support conditions) based on stress stiffening, and the combination with a numerically efficient algorithm, i.e., Nelson’s method. One of the main advantages of the employed damage diagnosis algorithm is that, although it uses physical models for damage detection, it considers the uncertainty in the data-driven features, which enables a reliabilitybased approach to determine the probability of detection. Moreover, the algorithm can be trained and the probability of detecting future damages can be predicted based on data and a model from the undamaged structure, in an unsupervised learning mode, making it particularly relevant for unique structures, where no data from the damaged state is available. For proof of concept, a numerical case study is presented. The study assesses the loss of prestress in a two-span reinforced concrete beam and showcases suitable validation approaches for the sensitivity calculation. T2 - International Symposium on Non-Destructive Testing in Civil Engineering (NDT-CE 2022) CY - Zurich, Switzerland DA - 16.08.2022 KW - Nelson’s method KW - Global ambient vibrations KW - Asymptotic local approach KW - Sensitivity vectors KW - Probability of detection KW - Stress stiffening PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-566632 DO - https://doi.org/10.58286/27311 SN - 1435-4934 VL - 27 IS - 9 SP - 1 EP - 13 PB - NDT.net CY - Kirchwald AN - OPUS4-56663 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Wiehle, Philipp T1 - Feuchteverhalten von Lehmsteinmauerwerk unter natürlichen Klimabedingungen N2 - Druckfestigkeit und Elastizitätsmodul von Lehmsteinmauerwerk nehmen mit steigendem Feuchtegehalt ab, weswegen die Mauerwerksdruckfestigkeit bei der Bemessung gemäß DIN 18940 in Abhängigkeit der maximal zu erwartenden Ausgleichsfeuchte abgemindert wird. Da bisher allerdings keine Messdaten zum Feuchtegehalt von Lehmsteinmauerwerk unter natürlichen Klimabedingungen vorliegen, stellen die normativen Grenzwerte lediglich eine konservative Abschätzung dar. Um die Feuchtegehalte von Lehmsteinmauerwerk und somit die Tragfähigkeit realitätsnah einschätzen zu können, wurden im Rahmen der vorliegenden Arbeit sowohl experimentelle als auch numerische Untersuchungen zum feuchtetechnischen Verhalten durchgeführt. Dabei wurden erstmalig magnetresonanzspektroskopische Untersuchungen an tragenden Lehmsteinen unterschiedlicher Herstellungsmethoden angewandt Weiterhin wurden Luftfeuchtesensoren in Lehmsteinmauerwerk eingebettet, um hygrische Langzeitfeuchtemessungen unter natürlichen Klimabedingungen durchzuführen. Auf Basis dieser Erkenntnisse wurde schließlich ein numerisches Modell kalibriert und Parameterstudien durchgeführt, um den unter realen Klimabedingungen tatsächlich auftretenden Feuchtegehalt im Lehmmauerwerk sowie dessen Verteilung über den Querschnitt einschätzen zu können und die normativen Grenzwerte zu überprüfen. Gezeigt wurde, dass die realitätsnahe instationäre Berechnung des Feuchtetransports mit üblichen hygrothermischen Simulationsprogrammen auf Basis einfacher feuchtetechnischer Kennwerte auch bei Lehmbaustoffen möglich ist. Der Einfluss des Quellens und Schwindens der enthaltenen Tonminerale und organischen Bestandteile wurde durch eine Modifikation bei der Ermittlung des Wasseraufnahmekoeffizienten explizit berücksichtigt und ist somit auch in den daraus abgeleiteten Transportkoeffizienten enthalten. Darüber hinaus wurde die Feuchtespeicherfunktion im überhygroskopischen Bereich auf Grundlage der Porenvolumenverteilung abgeschätzt. Die Approximation der Transportkoeffizienten und der Feuchtespeicherfunktion stellt dabei eine wesentliche Vereinfachung für Lehmbaustoffe dar, da ihre experimentelle Bestimmung aufgrund des Kontaktes mit Flüssigwasser kaum möglich ist. In Bezug auf das Feuchteverhalten üblicher Außenwandaufbauten von Wohnräumen konnte festgestellt werden, dass die Ausgleichsfeuchte im Lehmsteinmauerwerk stets unterhalb des in Nutzungsklasse 1 gemäß DIN 18940 zulässigen Grenzwertes von 65 % liegt. Je nach Putzsystem und Dämmstoff reduziert sich die Ausgleichsfeuchte auf Werte unter 60 %, wobei sich eine annähernd gleichmäßige Verteilung der Feuchte über den Mauerwerksquerschnitt hinweg einstellt. Bei Außenwänden von unbeheizten Räumen ergab sich eine maximale Ausgleichsfeuchte, die über weite Teile des Querschnitts unterhalb von 80 % lag. Der Ansatz einer maximalen Ausgleichsfeuchte von 90 % in Nutzungsklasse 2 ist folglich zu hoch angesetzt. Die zulässige Ausgleichsfeuchte bzw. der Umgebungsfeuchtefaktor in Nutzungsklasse 2 sollte dementsprechend angepasst werden. T2 - LEHM 2024 - 9. Internationale Fachtagung für Lehmbau CY - Weimar, Germany DA - 27.09.2024 KW - Lehm KW - Mauerwerk KW - Feuchte KW - Tragverhalten KW - Bemessung PY - 2024 AN - OPUS4-61904 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Unger, Jörg F. T1 - Digital Twins for materials and structures N2 - A safe and robust performance is a key criterion when building and maintaining structures and components. Ensuring this criterion at different stages of the lifetime can be supported by applying continuous monitoring concepts. The latter usually can serve multiple purposes, including the determination of material parameters for the design phase, the evaluation of the actual loading/environmental conditions (instead of using conservative estimates that are usually larger) and evaluating or predicting the true performance of the structure (thus decreasing the model bias). In this context, a digital twin of the structure has many benefits. In addition, it allows to introduce virtual sensors to “measure” sensor information that is e.g. inaccessible or unmeasureable. In the limit, the remaining useful life of a structure can be interpreted as a property that can be “measured” indirectly via the numerical model in combination with real sensor data. In order to efficiently use monitoring techniques in the context of a digital twin, it is important to consider the complete chain of information including the choice of sensors, the data processing and structuring, the modelling assumptions, the numerical simulation and finally the stochastic nature of the model prediction. In this presentation, challenges in this context are discussed with a specific focus on Bayesian model updating of the digital twin, accounting for both parameter updates as well as model bias that results from the limitations of modelling assumption. A bottleneck in this approach is the computational effort related to sampling methods such as Markov chain Monte Carlo methods that require many evaluations of the forward model. An alternative to the expensive computation of the forward model for updating the digital twin is the combination with model reduction techniques such as the Proper General Decomposition. The results are illustrated for several examples and scales, ranging from digitals twin for material tests in the lab over lab scale structural digital twins up to damage identification in field experiments. T2 - 1st International Workshop on Metrology for virtual measuring instruments CY - Berlin, Germany DA - 21.09.2021 KW - Digital twin for monitoring KW - Digital Twins for materials and structures PY - 2021 AN - OPUS4-53879 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Krankenhagen, Rainer T1 - Photothermal investigation of original and degraded asphalt N2 - Asphalt is one of the most common materials used in road construction. It is subject to both chemical and structural aging processes during use. At least to our knowledge, it is not currently known whether these aging processes also lead to a measurable change in the thermal properties of asphalt. If so, these changes could be exploited for non-destructive testing of the aging condition in situ. Photothermal analysis of a component surface involves looking at the time course of the surface temperature during and after pulse-like heating with an expanded laser beam. In the case of concrete surfaces, this method works well under laboratory conditions. It allowed the determination of the thermal effusivity. Now it should be investigated whether the photothermal signal allows conclusions to be made regarding the aging state of the asphalt. Within the scope of this paper, 2 asphalt specimens were investigated: a closed asphalt with 3% void content (SMA 11S) and an open-pore asphalt with 25% void content (PA 8). Both samples were artificially degraded according to a standardized procedure, leaving a portion of the surface unaffected. Subsections from both areas were then separated for photothermal testing. It was found, that the photothermal method is apparently not sensitive enough to detect aging on asphalt in general. However, it is noteworthy that both asphalt types heat up significantly faster than would be expected from the theory of heat conduction, which might be explained by the specific microstructure. T2 - 22nd Conference ECTP "European Confence on thermophysical properties" CY - Venice, Italy DA - 10.09.2023 KW - Asphalt KW - Ageing KW - Photothermal PY - 2023 AN - OPUS4-58857 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Seher, Julia T1 - Ein hydrothermaler Verwertungsweg für Mauerwerkbruch N2 - Mauerwerkbruch setzt sich aus unterschiedlichen Anteilen der üblichen Wandbaustoffe Ziegel, Beton- und Leichtbeton, Kalksandstein, Porenbeton sowie Mauer- und Putzmörtel zusammen. Bei seiner mechanischen Aufbereitung zum RC-Gemisch fallen häufig bis zu 50 % Feinanteile an. Die heterogene Zusammensetzung und der hohe Feinanteil verhindern eine Wiederverwertung nach einer einfachen mechanischen Aufbereitung. Eine Möglichkeit des Recyclings von Mauerwerkbruch ist aber ein hydrothermaler Stoffwandlungsprozess, durch den leichte poröser Granulate hergestellt werden. Aus ziegelhaltigem Mauerwerkbruch werden unter Zusatz von Branntkalk nach dem Mahlen, Mischen und Granulieren des Rohmehls durch hydrothermale Verfestigung in einem Autoklav poröse Körnungen mit Rohdichten kleiner als 2000 kg/m³, die Hydrothermalgranulate, erhalten. Die Erhärtung erfolgt bei ca. 200 °C und 1,6 MPa Sattdampf ähnlich dem Prozess der Kalksandsteinherstellung. Festigkeit und Gefüge der Hydrothermalgranulate entwickeln sich durch die Ausbildung von Calciumsilicathydraten (CSH-Phasen), die durch die Reaktion zwischen Quarz, als Bestandteil von Mauerwerkbruch, und Kalk entstehen. Über die Mischungszusammensetzung und die Reaktionsbedingungen können die Eigenschaften der Granulate gezielt gesteuert werden. Ihr Materialgefüge ist durch ein ungeordnetes System an Mesoporen und kleinen Makroporen mit Porenweiten kleiner 100 nm gekennzeichnet. Damit unterscheiden sich ihre Eigenschaften deutlich von denen der thermisch erhärteten Blähgranulate, da sich durch die CSH-Phasen eine ganz andere Gefüge- und Porenstruktur ausbildet. Aus den Granulateigenschaften ergeben sich Anwendungen als Filter- oder Speichermaterial, d.h. Applikationen, die über den Baustoffsektor hinausgehen. In einem laufenden Forschungsprojekt wird mit 4 Industrie- und 2 Forschungspartnern aus den Bereichen Baustoffrecycling, Verfahrens- und Syntheseentwicklung, Partikelcharakterisierung so-wie Filter- und Betontechnologie ein Syntheseweg zur gezielten Herstellung hydrothermal erhärteter, körniger und poröser Produkte aus Mauerwerkbruch im Labor- und Pilotmaßstab entwickelt. Dazu gehört auch die Untersuchung aller Prozessschritte von der Aufbereitung der Ausgangsmaterialien über das Homogenisieren und Granulieren der Mehle bis zur hydrothermalen Behandlung der Granulate. Die Hydrothermalgranulate werden umfangreichen Eignungs- und Dauerhaftigkeitstests unterzogen. Das aktuelle Forschungsvorhaben und insbesondere erste Ergebnisse zur hydrothermalen Synthese von Mauerwerkbruch-Kalk-Mischungen werden im Vortrag vorgestellt. T2 - Fachtagung Recycling R'19 CY - Weimar, Germany DA - 25.09.2019 KW - Poröse Granulate KW - Rohstoffliches Recycling KW - Mauerwerkbruch PY - 2019 AN - OPUS4-49371 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Stelzner, Ludwig A1 - Eiz Eddin, Ahmad A1 - Häßler, Dustin A1 - Hothan, Sascha T1 - Zum Feuerwiderstand vorgespannter Carbonbetondecken N2 - Der Einsatz von hoch zugbeanspruchbarem und korrosionsbeständigem Carbongelege anstelle herkömmlichen Spannstahls ermöglicht es Beton vorzuspannen und gleichzeitig die Betondeckung auf ein für den Verbund nötiges Minimum zu reduzieren. Der Wechsel von massiven zu filigranen Bauteilen führt in der Regel aufgrund der geringeren thermischen Masse zu einer Abnahme des Feuerwiderstandes. Der Beitrag stellt Versuchsergebnisse zum Abplatz- und Hochtemperaturverhalten von Carbonbeton vor, die im Rahmen des Verbundvorhabens „Vorgespannte Carbonbetondecken mit reduzierten Querschnitten“ (CaPreFloor) erzielt wurden. Für die Untersuchung der Tragfähigkeit bei hohen Temperaturen wurden 4-Punktbiegeversuche mit instationärer Temperaturbeanspruchung an vorgespannten Carbonbetonplatten bei Variation des Carbongeleges und des Vorspanngrades durchgeführt. Ferner erfolgte die Analyse der Abplatzneigung an bewehrten und unbewehrten Bauteilen mittels Brandversuchen unter Einheits-Temperaturzeitkurve. T2 - 16. Carbonbetontage 2024 CY - Dresden, Germany DA - 24.09.2024 KW - Carbonbeton KW - Feuerwiderstand KW - Abplatzverhalten PY - 2024 SP - 56 EP - 57 AN - OPUS4-62430 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Diercks, Philipp T1 - Physically meaningful samples in randomized local model order reduction N2 - In this contribution, a methodology for fine scale modeling of large scale structures is proposed, which combines the variational multiscale method[1], domain decomposition and model order reduction. The influence of the fine scale on the coarse scale is modelled by the use of an additive split of the displacement field, addressing applications without a clear scale separation. Based on the work of Buhr and Smetana[2], local reduced spaces are constructed by solving an oversampling problem with random boundary conditions. Herein, we inform the boundary conditions by a global reduced problem and compare our approach using physically meaningful correlated samples with existing approaches using uncorrelated samples. The local spaces are designed such that the local contribution of each subdomain can be coupled in a conforming way, which also preserves the sparsity pattern of standard finite element assembly procedures. Several numerical experiments show the accuracy and efficiency of the method, as well as its potential to reduce the size of the local spaces and the number of training samples compared to the uncorrelated sampling. T2 - XVII International Conference on Computational Plasticity, COMPLAS 2023 CY - Barcelona, Spain DA - 05.07.2023 KW - Domain Decomposition KW - Localized model order reduction KW - Multiscale method KW - Variational Multiscale Method PY - 2023 AN - OPUS4-58658 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Brighenti, Francesca A1 - Caspani, Valeria Francesca A1 - Costa, Giancarlo A1 - Giordano, Pier Francesco A1 - Limongelli, Maria Pina A1 - Zonta, Daniele T1 - Bridge management systems: A review on current practice in a digitizing world N2 - Bridges are subject to a plethora of deterioration phenomena, such as corrosion, fatigue, and damaging events (e. g., truck impacts and earthquakes) that can affect their performance and compromise functionality and safety. These challenges, along with the expansion of physical infrastructures and limited economic resources, underscore the need for effective management systems to enhance the efficiency of maintenance activities. To address this need, bridge operators have developed Bridge Management Systems (BMSs), which assist in ensuring safe operations while optimizing budget allocation and intervention strategies. Existing state-of-the-art studies on BMSs, dating back several years, primarily focus on specific aspects of BMSs and do not provide exhaustive insight into the implemented processes. Consequently, a comprehensive analysis of the entire process is currently lacking. This review organizes and discusses the key features of existing BMSs and introduces a novel definition of BMS modules — data management, diagnosis, prognosis, and decision-making — where consensus is currently lacking. The paper covers the historical and current practices of the most common BMSs, outlining the main principles of each phase along with their critical aspects and future trends. KW - Bridge management system KW - Digitalization KW - Automation KW - Inspection KW - Structural health monitoring KW - Digital twin KW - Decision making KW - Life-cycle analysis PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-628380 DO - https://doi.org/10.1016/j.engstruct.2024.118971 SN - 0141-0296 VL - 321 SP - 1 EP - 21 PB - Elsevier CY - Amsterdam AN - OPUS4-62838 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Pirskawetz, Stephan A1 - Steinbock, O. A1 - Hille, Falk A1 - Schmidt, S. A1 - Hofmann, Detlef T1 - Erfahrungen aus dem Rückbau der Brücke am Altstädter Bahnhof in der Stadt Brandenburg - Teil 2: Schadensmonitoring bei zerstörenden Versuchen N2 - Im Dezember 2019 wurden bei einer turnusmäßigen Inspektion der B 1-Brücke am Altstädter Bahnhof in Brandenburg an der Havel massive und schnell voranschreitende Schäden festgestellt. Als Ursache für die Risse entlang der Längsträger wurde das Versagen eines signifikanten Anteils der Spanndrähte der konzentrierten Spannglieder vermutet. Die Brücke wurde umgehend für den Verkehr gesperrt und im Mai 2021 gesprengt. Im Vorfeld der Sprengung wurden durch das Bundesministerium für Digitales und Verkehr (BMDV) weiterführende Untersuchungen zum Schadensbild veranlasst, welche vom Landesbetrieb Straßenwesen Brandenburg koordiniert und in den Bauablauf integriert wurden. Das von der Hochschule für Technik und Wirtschaft (HTW) Dresden erstellte Versuchskonzept ist Bestandteil des vorangestellten ersten Teils des Beitrags [1]. Hier im zweiten Teil werden ausgewählte Ergebnisse der umfangreichen versuchsbegleitenden Mess- und Monitoringmaßnahmen beschrieben, welche in Kooperation der HTW Dresden, der Bilfinger Noell GmbH sowie der Bundesanstalt für Materialforschung und -prüfung (BAM) durchgeführt wurden. N2 - A routine inspection of the B1 bridge at the Altstädter Bahnhof in Brandenburg an der Havel in December 2019 revealed massive and rapidly progressing damage. The cause of the cracks along the longitudinal girders was suspected to be the failure of a significant portion of the prestressing wires of the concentrated tendons. The bridge was immediately closed to traffic and demolished in May 2021. Prior to the demolition, the Federal Ministry for Digital and Transport (BMDV) initiated further investigations into the damage pattern, which were coordinated and integrated into the deconstruction process by the Landesbetrieb Straßenwesen Brandenburg. The test concept was developed by the Hochschule für Technik und Wirtschaft Dresden (HTW) and is described in the previous article (Part 1). The article at present (Part 2) describes selected results of the extensive measurement and monitoring measures accompanying the tests. The Tests were carried out in cooperation with the HTW Dresden, Bilfinger Noell GmbH and the Bundesanstalt für Materialforschung und -prüfung (BAM). KW - Spannbetonbrücke KW - Spannstahlbruch KW - Schallemission KW - Fotogrammetrie KW - Faseroptik KW - Stochastische Subspacebasierte Schadensdetektion PY - 2022 DO - https://doi.org/10.1002/best.202200052 SN - 1437-1006 VL - 117 IS - 8 SP - 581 EP - 589 PB - Ernst & Sohn CY - Berlin AN - OPUS4-55513 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Pittrich, Tim A1 - Stelzner, Ludwig A1 - Weise, Frank T1 - Fire-induced spalling of normal strength concrete with different types of blended Portland cement N2 - The cement industry is looking to reduce its overall CO2 footprint. Greener manufacturing can be achieved by the introduction of more clinker-reduced cements. Concrete exposed to fire tends to show explosive spalling caused by thermomechanical and thermohydraulic processes. It is therefore essential to determine how concretes with clinker-reduced cements behave under fire exposure, especially for concretes containing calcined clays, as these are expected to be the supplementary cementitious material of the future. In this paper, normal strength concretes with four different cements (CEM I, CEM II/A-LL, CEM III/A and CEM II/B-Q) were examined for their fire-induced spalling behaviour. In addition, a mix with PP fibres was investigated for each concrete. The experiments were conducted on ring-restrained cylindrical specimens exposed to the hydrocarbon fire curve. The results showed that the cement type influences spalling behaviour. Samples with CEM I spalled the least, followed by CEM II/A-LL and CEM III/A. Finally, samples with CEM II/B-Q showed the most severe damage. It was found that the spalling behaviour of different concretes correlates with the moisture content before exposure to fire, meaning that higher moisture content leads to higher spalling susceptibility. The use of 2 kg/m³ PP fibres completely inhibited spalling regardless of the cement type used and therefore remains a successful avoidance strategy. T2 - Structures in Fire 2024 CY - Coimbra, Portugal DA - 19.06.2024 KW - Fire-induced concrete spalling KW - Concrete KW - Blended Portland cement KW - SCM KW - PP-fibres PY - 2024 SN - 978-989-35292-2-5 DO - https://doi.org/10.30779/cmm_SIF24 VL - 1st Edition SP - 461 EP - 471 AN - OPUS4-60809 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Dombrowski, M. A1 - Hückler, A. A1 - Stelzner, Ludwig A1 - Häßler, Dustin A1 - Heidemann, L. A1 - Reinhold, S. A1 - Zeitler, B. A1 - Früke, J. A1 - Lenz, T. A1 - Theuerkauf, H. A1 - Söll, S. A1 - Reyher, B. A1 - Schlaich, M. T1 - Innovative lightweight floors made of prestressed CFRP-reinforced concrete – from research to construction practice N2 - The presented joint research project “CaPreFloor”, which started in 2023, aims to employ prestressed textile-reinforced concrete using carbonfibre-reinforced polymer (CFRP) to design lightweight floor elements. This allows the reduction of common steel-reinforced concrete floors of 30 cm thickness to a maximum of 6 cm for office, residential, and hotel buildings. Lower material consumption significantly contributes to the conservation of resources and minimises the carbon footprint. In addition, the prefabrication of these floor elements results in high and consistent quality, short construction times and enhanced reusability of the components. A team of experts from various research and practice fields works on this project to achieve the set goal. Currently, open questions include the anchorage and load transfer of the prestressed CFRP reinforcement, structural failure indication, the behaviour of CFRP reinforcement and high-performance concrete at elevated temperatures, as well as fire resistance and sound insulation. As a result, an extensive test programme on different size scales will be conducted. Practical aspects, such as design, field of application and life cycle, as well as the development of an automated production plant, are also considered. The paper will present considerations related to the geometry and design, material selection, manufacturing, ecological footprint, and intended experimental test programme. Four different geometries and two different CFRP reinforcements are being examined. As a result, the developed floor must fulfil all practical requirements in building construction. T2 - XI International Symposium on Fiber Reinforced Concrete (Befib 2024) CY - Dresden, Germany DA - 15.09.2024 KW - Lightweight floor system KW - Prestressed CFRP concrete KW - Fire resistance KW - Sound insulation PY - 2024 SP - 246 EP - 256 AN - OPUS4-62431 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Recknagel, Christoph T1 - Innovative Versuchsmethodik - INFUKON Performance-orientierte Dauerhaftigkeitsuntersuchung gefügter Bauteile/Konstruktionen N2 - Permanent erfolgen konstruktive Verbesserungen der Bauwerke, stoffliche Weiterentwicklungen der Baustoffsysteme sowie technologische Optimierungen der Bauprozesse. Insbesondere für Fugenkonstruktionen und Fugenfüllstoffsysteme fehlt ein realitätsnahes, stoffneutrales und vergleichbares versuchstechnisches Untersuchungs- und Bewertungskonzept. Der Posterbeitrag „Innovative Versuchsmethodik - INFUKON" möchte auf eine neu entwickelte Versuchsmethodik zur Funktions- und Dauerhaftigkeitsuntersuchung von Fugenlösungen im Bauwesen hinweisen. Methodische Grundlage der erforderlichen Neuentwicklung ist eine funktionsanalytische Herangehensweise entsprechend dem „performance concept". Aus der Analyse der maßgebenden Einwirkungen und daraus erforderlichen Funktions- und Dauerhaftigkeitsprinzipien wurde ein multimodal aufgebauter Versuchsstand mit größtmöglicher Einsatzvielfalt entwickelt. Verschiedenartige mechanische Einwirkungen in mehraxialer Wirkrichtung können einzeln oder in unterschiedlichster Kombination mit verschiedenartigen klimatischen und zusätzlichen Sonderbeanspruchungen überlagert auf realitätsnah aufgebaute Systemprobekörper aufgebracht werden. Die derart frei konfigurierbaren Beanspruchungsfunktionen können die maßgebenden Beanspruchungszustände bauteilgerecht widerspiegeln. Erstes Anwendungsgebiet sind Untersuchungen zur Optimierung des Fugenbereiches von hochbeanspruchten Betonfahrbahndecken. Eine Übertragung der Versuchsmethodik auf weitere Dehnfugenkonstruktionen oder aber auch Funktions- und Dauerhaftigkeitsuntersuchungen sonstiger gefügte Bauteile wurde weitestgehend im gefundenen versuchstechnischen Lösungsansatz implementiert. T2 - Jubiläumskongress 100 Jahre Deutscher Straßen- und Verkehrskongress CY - Bonn, Germany DA - 23.10.2024 KW - Innovative Versuchsmethodik KW - Infrastruktur KW - Performance-concept KW - Innovative Untersuchungsmethodik PY - 2024 AN - OPUS4-61467 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Baier, Johanna T1 - Structural design of rammed earth considering the impact of moisture N2 - In March 2024, a research project was initiated at BAM with the aim of developing a design concept for rammed earth construction. It is based on experimental and numerical investigations into the mechanical load-bearing behaviour at both material and component level. As the mechanical parameters of earth building materials are strongly dependent on material moisture, the moisture behaviour of rammed earth is also being investigated in more detail. T2 - LEHM 2024 - 9. Internationale Fachtagung für Lehmbau CY - Weimar, Germany DA - 27.09.2024 KW - Rammed earth KW - Structral design KW - Material moisture PY - 2024 AN - OPUS4-62031 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Diercks, Philipp A1 - Robens-Radermacher, Annika A1 - Rosenbusch, Sjard Mathis A1 - Unger, Jörg F. A1 - Saif-Ur-Rehman, Saif-Ur-Rehman T1 - fenics-constitutive N2 - This software enables the use of nonlinear constitutive models with FEniCSx. KW - Constitutive models KW - FEniCSx KW - Fenics-constitutive PY - 2024 DO - https://doi.org/10.5281/zenodo.13364955 PB - Zenodo CY - Geneva AN - OPUS4-62114 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Robens-Radermacher, Annika A1 - Strobl, Dominic T1 - PGDrome N2 - A FEniCS based python module of the Proper Generalized Decomposition (PGD) method. KW - Reduced Order Model KW - Proper Generalized Decomposition KW - Fenics PY - 2023 DO - https://doi.org/10.5281/zenodo.10075334 PB - Zenodo CY - Geneva AN - OPUS4-59134 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CHAP A1 - Oesch, Tyler A1 - Stelzner, Ludwig A1 - Weise, Frank ED - Herrmann, H. ED - Schnell, J. T1 - Non-destructive evaluation of the contribution of polymer-fibre orientation and distribution characteristics to concrete performance during fire N2 - Although concrete itself is not a combustible material, concrete mixtures with high density, such has high-performance concretes (HPCs), are susceptible to significant damage during fires due to explosive spalling. Past research has shown that the inclusion of polymer fibres in high density concrete can significantly mitigate this fire damage. The exact mechanisms causing this increased spalling resistance are not yet fully under-stood, but it is thought that the fibres facilitate moisture transport during fire exposure, which in turn contributes to relief of internal stresses in the spalling-susceptible region. In this study, X-ray Computed Tomography (CT) was applied to observe the interaction between polymer fibres and cracking during thermal exposure. For this purpose, two concrete samples containing different polymer fibre types were subjected to incremental application of a defined thermal exposure. CT images were acquired before and after each thermal exposure and powerful image processing tools were used to segment the various material components. This enabled a detailed analysis of crack formation and propagation as well as the visualization and quantification of polymer fibre characteristics within the concrete. The results demonstrated that the orientation of both fibres and cracks in polymer-fibre reinforced concrete tend to be anisotropic. The results also indicated that crack geometry characteristics may be correlated with fibre orientation, with cracks tending to run parallel to fibre beds. Clear quantitative relationships were also observed between heating and increasing cracking levels, expressed in terms of both crack surface area and crack volume. KW - X-ray Computed Tomography (CT) KW - Polypropylene Fibres KW - Fire Performance KW - Fibre-Reinforced Concrete (FRC) KW - Fibre Orientation Analysis PY - 2019 SN - 978-3-030-00868-0 DO - https://doi.org/10.1007/978-3-030-00868-0 SP - 51 EP - 73 PB - Springer Nature Switzerland AG AN - OPUS4-47206 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kruschwitz, Sabine T1 - Ortsaufgelöste NMR-Relaxometrie an mineralischen Baustoffen N2 - Zahlreiche Schädigungsprozesse in Baustoffen stehen im engen Zusammenhang mit Feuchteeintrag und Feuchtetransport. Als Beispiel sind die schädigende Alkali-Kieselsäurereaktion (AKR) von Beton sowie Frost-Tauwechsel induzierte Gefügeschäden genannt. Zur zerstörungsfreien, ortsaufgelösten Feuchtemessung eignet sich die im Bereich der Geophysik etablierte, aber im Bauingenieurwesen noch wenig verbreitete, Messmethode der Nuklear Magnetischen Resonanz (NMR). Unter Verwendung der NMR-Relaxometrie sind sowohl Aussagen zum Feuchtegehalt und dessen räumliche Verteilung als auch die Charakterisierung der Porengrößen möglich, die das Transportverhalten eines porösen Materials maßgeblich beeinflussen. Zur Erfassung der Mikro- und Mesoporen in Baustoffen ist dabei die Auflösung von kurzen T2 Relaxationszeiten unabdingbar. Bisher ist es mit gängigen NMR-Laborgeräten nur begrenzt möglich, solche kurzen T2-Zeiten schichtselektiv zu erfassen. Vor diesem Hintergrund wurde ein speziell für die Messung an mineralischen Baustoffen optimierter NMR-Tomograph beschafft. Dieser ermöglicht sowohl schichtselektive Messungen von Bohrkernen mit Durchmessern von bis zu 70 mm als auch bildgebende Untersuchungen an Proben mit Durchmessern ≤ 40 mm. Erste Untersuchungsergebnisse an Sandstein, Tuffstein und Beton zeigen die Leistungsfähigkeit des neuen NMR-Tomographen zur Erfassung der porengrößenspezifischen Feuchteverteilung. In diesem Beitrag werden erste Ergebnisse verschiedenartiger Laborversuche exemplarisch dargestellt. Für Sandsteine mit unterschiedlichsten Porengrößenverteilungen wurden mit dem neuen NMR-Tomographen und einem herkömmlichen NMR-System vergleichbare T2 Zeitenverteilungen ermittelt. Am sehr heterogenen Tuffstein konnten unterschiedlich poröse (und feuchte) Bereiche räumlich aufgelöst werden. Im Beton ließ sich der Feuchtetransport im Zementstein porengrößenspezifisch, schichtselektiv und zeitlich aufgelöst verfolgen. Die bisher gewonnenen Ergebnisse zeigen das breite Anwendungsspektrum des neuen NMR Tomographen auf und ermöglichen ein besseres Verständnis des Feuchtetransports und der oft damit einhergehenden Schädigungsprozesse in Baustoffen. T2 - 79. Jahrestagung Deutsche Geophysikalische Gesellschaft CY - Brunswick, Germany DA - 04.03.2019 KW - Concrete KW - NMR KW - Sandstone KW - Capillary suction PY - 2019 N1 - Geburtsname von Munsch, Sarah Mandy: Nagel, S. M. - Birth name of Munsch, Sarah Mandy: Nagel, S. M. AN - OPUS4-47501 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Nerger, Deborah T1 - Impact damage characterization at RC plates with planar tomography and FEM N2 - Prediction of dynamic effects of reinforced concrete structures under impact loading is a technical challenge. This is a consequence of the great variability of the physical properties resulting from the wide adaptability of reinforced concrete and a consequence of the wide range of impact loading. Experiments and numerical investigations are normally used on a small scale to address the problem. In this paper, impact tests on reinforced conrete plates with the lateral dimensions of 1.5 m x 1.5 m and a thickness of 30 cm are presented. In bending reinforcement, besides the velocity two properties are varied, the diameter and the spatial distribution of the rebars. Experiments are performed at the Otto-Mohr-Laboratory of the Institute of Concrete Structures of the Technische Universit¨at Dresden. Due to the accelerated fall of the impactor the velocity ranges between 20 and 70 m/s. In addition to the measured quantities such as bearing forces, accelerations are also measured at 4 different positions on and under the plate, as well as the deflection at several positions. The measured data are used for the analysis of the damage form and the numerical examinations with the program Ansys Autodyn and the material model after Drucker-Prager. Numerical investigations support the tests, with detailed analysis of individual effects. These numerical computations and the planar tomographic investigations were carried out at BAM in Berlin. With the help of planar tomographic evaluation, the damaged structure is made visible and compared with the numerical results. Influences of the bending reinforcement are explained on the basis of damage evaluation in the local area and on selected measured values. In addition to the test evaluation, the tomographic and numerical methods are presented. T2 - XI International Conference on Structural Dynamics (EURODYN 2020) CY - Online meeting DA - 23.11.2020 KW - Post-impact evaluation KW - Damage characterization KW - Planar tomography KW - Drucker-Prager KW - Ansys Autodyn PY - 2020 AN - OPUS4-51768 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Andrés Arcones, Daniel T1 - Modell- und Parameterunsicherheiten am Beispiel eines Digitalen Brückenzwillings N2 - Digitale Zwillinge bieten wertvolle Einblicke in das Verhalten von Bauwerken und ermöglichen eine fundierte Entscheidungsfindung. Durch den Einsatz von Simulationen, die auf physikalischen Gesetzen beruhen, ist es möglich, Vorhersagen über die Struktur auf der Grundlage zukünftiger oder hypothetischer Situationen zu treffen. Die Verwendung solcher Simulationen impliziert jedoch eine Reihe von Annahmen und Vereinfachungen, die unvermeidbare Fehler in die Vorhersagen einbringen. Die Quantifizierung dieser Unsicherheiten ist der Schlüssel für den Einsatz zuverlässiger digitaler Zwillinge von Brücken. T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM Green Intelligent Building CY - Berlin, Germany DA - 16.10.2024 KW - Unsicherheiten Quantifizierung KW - Brückenüberwachung KW - Digitaler Zwilling PY - 2024 AN - OPUS4-61568 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Munsch, Sarah Mandy T1 - Anwendung von KI für die Materialoptimierung im Bauwesen N2 - Diese Arbeit untersucht den Einsatz von Künstlicher Intelligenz (KI) in der Materialentwicklung für Beton, mit einem Fokus auf Karbonatisierungswiderstand, CO₂-Reduktion und Kostenoptimierung. Das KI-Tool SLAMD, das auf inverses Materialdesign setzt, konnte in Studien die Entwicklungszeit für Betonmischungen um bis zu 80 % verkürzen. Durch die Integration zusätzlicher 1H-Kernspinresonanz-Daten wurde der Prozess um weitere 40 % beschleunigt. Insgesamt zeigt sich, dass der Einsatz von KI die Effizienz und Nachhaltigkeit in der Materialentwicklung signifikant steigern kann. T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM Green Intelligent Building CY - Berlin, Germany DA - 16.10.2024 KW - Cement & Concrete KW - SLAMD app KW - Nuclear magnetic KW - Resonance KW - Carbonation resistance PY - 2024 AN - OPUS4-61423 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Rosenbusch, Sjard Mathis A1 - Diercks, Philipp A1 - Kindrachuk, Vitaliy A1 - Unger, Jörg F. T1 - Integrating custom constitutive models into FEniCSx: A versatile approach and case studies N2 - The development and integration of user-defined constitutive relationships into finite element (FE) tools using standardized interfaces play a pivotal role in advancing the capabilities of FE solvers for structural mechanics applications. While commercial FE solvers like Abaqus and Ansys have designed their interfaces to provide custom stresses, tangents, and updated history variables, the open-source solver FEniCSx remains efficient only when the constitutive update has an analytical representation. This restricts the application of FEniCSx for non-linear structural mechanics. Since FEniCSx has become a powerful and popular open-source tool for solving partial differential equations, particularly due to its automatic computation of Hessians, we aim to develop a generalized interface to enhance its capability for constitutive modeling. This approach will address complex constitutive equations that require iterative solutions at the quadrature point level. Specific implementation challenges, such as using return-mapping procedures, can then be managed commonly. The provided interface for custom constitutive models offers a versatile way to implement them in various languages, including C++, Python, Rust, and Fortran. Finally, using the example of UMATs for viscoplastic models, we demonstrate how available user subroutines can be incorporated into the interface while maintaining computational performance of FEniCSx comparable to that of Abaqus. KW - Finite element method KW - Constitutive models KW - FEniCSx KW - UMAT KW - Rust KW - Python KW - C++ PY - 2024 DO - https://doi.org/10.5281/zenodo.13980988 PB - Zenodo CY - Geneva AN - OPUS4-62112 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Seher, Julia T1 - Hydrothermalgranulate - Verwertungsmöglichkeit für Mauerwerkbruch N2 - Jährlich fallen in Deutschland etwa 75 Mio. t mineralische Bau- und Abbruchabfälle an, die eine vielfältig einsetzbare sekundäre Rohstoffquelle darstellen. Trotz hoher Verwertungsquoten werden Bau- und Abbruchabfälle zum Teil deponiert oder nur in Anwendungen mit geringen Qualitätsanforderungen eingesetzt, weil geeignete hochwertige Verwertungswege für solche sehr heterogen zusammengesetzte Körnungen mit hohem Feinanteil fehlen. Der Reststoff Mauerwerkbruch ist ein heterogenes SiO2-reiches Gemisch aus Ziegel-, Beton- und Leichtbeton-, Kalksandstein- und Porenbetonbruch sowie Putz- und Mörtelanhaftungen. Die uneinheitliche Zusammensetzung und mehr als 50 % Feinanteile durch die mechanische Aufbereitung verhindern eine unmittelbare Wiederverwertung als rezyklierte Gesteinskörnung. Eine Möglichkeit der effektiven Verwertung von Mauerwerkbruch stellt das rohstoffliche Recycling über einen hydrothermalen Stoffumwandlungsprozess dar, bei dem poröse Granulate entstehen. Aus den Eigenschaften der Hydrothermalgranulate, insbesondere ihrer Porenstruktur, ergeben sich Anwendungsmöglichkeiten als Filter- oder Speichermaterial, d. h. auch in Bereichen, die über den Bausektor hinausgehen. Hierbei können die Granulate Gesteinskörnungen natürlichen Ursprungs, z. B. Lavasand und Bims, oder aus natürlichen Rohstoffen hergestellte Körnungen, z. B. Blähtone, ersetzen. Somit wird ein Beitrag zur Schonung natürlicher Ressourcen und zur Energieeinsparung im Vergleich zur Blähtonherstellung geleistet. Ziel des ZIM-Kooperationsprojekts „HYTEGRA – Hydrothermalgranulate“ war die Entwicklung des Verfahrens zur Herstellung leichter Gesteinskörnungen durch die hydrothermale Behandlung eines Gemischs quarz- und kalkreicher Reststoffe. Als Ausgangsstoffe dienten ziegelhaltiger Mauerwerkbruch als SiO2-Träger und Papierasche aus dem Altpapierrecycling als CaO-Träger. Die vollständige Prozesskette von der mechanisch-physikalischen Aufbereitung der Reststoffe über die Formgebung der Grüngranulate bis zur hydrothermalen Härtung der Leichtgranulate wurde im Labormaßstab entwickelt und erprobt. Die Anwendung der Hydrothermalgranulate als Speichermaterial zur inneren Nachbehandlung von Beton und als Pflanzsubstrat sowie als Filtermaterial in Bodenfiltern zur Abwasserbehandlung wurde untersucht. Im Vortrag wird ein Überblick über die Ergebnisse des erfolgreich abgeschlossenen Projekts „HYTEGRA“ gegeben. T2 - Kolloquium der Leibniz-Sozietät der Wissenschaften zu Berlin: Die Energiewende 2.0 - Im Fokus: Die Stoffwirtschaft CY - Potsdam, Germany DA - 09.06.2023 KW - Mauerwerkbruch KW - Poröse Granulate KW - Rohstoffliches Recycling KW - Papierasche KW - Leichte Gesteinskörnung PY - 2023 AN - OPUS4-57639 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Pirskawetz, Stephan A1 - Schmidt, S. A1 - Steinbock, O. T1 - Rückbau der Brücke Altstädter Bahnhof, Brandenburg/Havel - Detektion von Spanndrahtbrüchen mit Schallemissionsanalyse N2 - Bei einer turnusmäßigen Inspektion der B1 Brücke am Altstädter Bahnhof in Brandenburg an der Havel wurden im Dezember 2019 Risse und Hohlstellen entlang der Längsträger festgestellt. Als Ursache wurde das Versagen eines signifikanten Anteils der Spanndrähte der konzentrierten Spannglieder vermutet. Die Brücke wurde umgehend für den Verkehr gesperrt und nach weiteren, umfassenden Untersuchungen im Mai 2021 abgebrochen. Um die Sicherheit des unter der Brücke geführten Verkehrs zu gewährleisten, wurde die Brücke unter anderem mit einem Schallemissionsmesssystem überwacht. Mit diesem Verfahren ist es möglich, Spanndrahtbrüche zuverlässig zu detektieren und zu lokalisieren. In dem gut einjährigen Überwachungszeitraum wurden mehr als einhundert Spanndrahtbrüche detektiert, die in einigen Bereichen der Brücke besonders konzentriert auftraten. Vor dem Abbruch der Brücke war es möglich, den Nachweis der Detektion von Spanndrahtbrüchen mit der Schallemissionsanalyse und ihre Ortungsgenauigkeit anhand von künstlich erzeugten Drahtbrüchen zu validieren. Weiterhin konnte das sichtbare Schadensbild, Längsrisse und Hohlstellen über den Spannkanälen, auf die lokale Schädigung der Spanndrähte zurückgeführt werden. Derzeit wird ein Merkblatt erarbeitet, in dem die Erfahrungen in der bisherigen Anwendung der Schallemissionsanalyse zum Monitoring von Spanndrahtbrüchen zusammengefasst werden. In diesem Beitrag werden die Grundlagen der Schallemissionsanalyse und die Ergebnisse der Validierungsversuche an der Brücke in Brandenburg dargestellt. Weiterhin werden die Vorteile und Grenzen der Brückenüberwachung mittels Schallemissionsanalyse sowie Maßnahmen zur Sicherstellung der Qualität und der Zuverlässigkeit diskutiert. T2 - 5. Brückenkolloquium CY - Esslingen, Germany DA - 05.09.2022 KW - Spannbeton KW - Spannstahlbruch KW - Schallemission KW - Brücke PY - 2022 SN - 978-3-8169-3549-0 SN - 978-3-8169-0125-9 SP - 549 EP - 553 PB - expert verlag - Narr Francke Attempto Verlag GmbH + Co. KG AN - OPUS4-55685 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Bos, Freek A1 - Robens-Radermacher, Annika A1 - Muthukrishnan, S. A1 - Versteegen, J. A1 - Wolfs, R. A1 - Santhanam, M. A1 - Menna, C. A1 - Mechtcherine, V. T1 - Database of the RILEM TC 304-ADC interlaboratory study on mechanical properties of 3D printed concrete (ILS-mech) N2 - The RILEM TC 304-ADC has set up a large interlaboratory study on the mechanical properties of 3D printed concrete (ILS-mech). The study was prepared in 2022 by a preparation group leading to a Study Plan which the TC approved on 29 November 2022 (https://doi.org/10.14459/2023mp1705940). The ILS-mech was performed in 2023. The data was collected using a pre-prepared spreadsheet template. For data management, a database was derived and set-up in openBIS. The underlying Postgres database of openBIS was exported to the here-published SQLite database for sharing without maintaining a server. The structure of the database is described in (doi). The results are discussed in three associated papers focusing on the overall outcomes and evaluation of the procedures (doi), the compressive test results (doi), and the tensile test results (doi). KW - Additive manufacturing of concrete KW - 3d concrete printing KW - 3dcp KW - Test protocol KW - Compression KW - Flexure KW - Tension KW - E-modulus KW - Bending KW - Splitting PY - 2023 PB - Zenodo CY - Geneva AN - OPUS4-61022 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schnell, A. A1 - Rübner, Katrin A1 - Ihlenfeldt, Toni A1 - Vöge, M. T1 - Leichtgranulate aus heterogenen Bau- und Abbruchabfällen N2 - Mineralische Bauabfälle stellen in den Industrienationen den größten Abfallstrom dar. Allein in Deutschland fallen jährlich mehr als 50 Mio. Tonnen Bauschutt an, der hauptsächlich aus Beton- und Mauerwerkbruch besteht. Dabei nehmen die Verwertungs- und Recyclingquoten bei den bereits etablierten herkömmlichen Einsatzgebieten für aufbereitete Bau- und Abbruchabfälle mit zunehmender Heterogenität des Materials ab. Ein höherwertiges Recycling mit dem Ziel das aufbereitete Material beispielsweise in Betonprodukten einzusetzen erfolgt heute in Deutschland lediglich im Rahmen von Pilotprojekten. So können die groben Körnungen des Betonbruchs als rezyklierte Gesteinskörnung im Beton eingesetzt werden. Besonders eingeschränkte Verwertungsmöglichkeiten liegen für Mauerwerkbruch vor, einem Gemisch aus Beton, Ziegel, Kalksandstein, Porenbeton, Mörtel, Natursteinen und anderen mineralischen Bestandteilen. Die Ursache hierfür ist neben der heterogenen Zusammensetzung des Materials auch dessen feine Kornverteilung, die durch den bei der mechanischen Aufbereitung zwangsläufig anfallenden Feinkornanteil von 30 bis über 40 Prozent bedingt ist. Defizite in der Verwertung bestehen also besonders bei heterogenen feinkörnigen Gemischen. Hier müssen Ansätze gefunden werden, um eine hochwertige Wiederverwertung zu ermöglichen. Dafür ist eine möglichst gute Trennung der einzelnen Materialfraktionen ein bewährter Ansatz. Während Metalle mittels Band- und Wirbelstromabscheidern und leichte Fremdbestandteile über Windsichtung und Dichtesortierung ausgetragen werden können, ist eine Trennung der Materialien Ziegel, Mörtel und Beton, insbesondere für die feinen Fraktionen, derzeit technologisch und wirtschaftlich nicht umsetzbar. Ein rohstoffliches Recycling dieser heterogen zusammengesetzten Abfälle unter Nutzung ihrer chemisch-mineralogischen Zusammensetzung ohne eine vorherige Trennung in die einzelnen Materialfraktionen bietet sich als Alternative an. Ergebnisse zur Herstellung von Leichtgranulaten aus Mauerwerkbruch und Tonen in einem thermischen Prozess ähnlich der Blähtonherstellung wurden bereits mehrfach veröffentlicht. Diese Recycling-Granulate (RCG) könnten unter anderem als leichte Gesteinskörnung für Betone verwendet werden. T2 - 24. Tagung Siedlungsabfallwirtschaft Magdeburg CY - Magdeburg, Germany DA - 18.09.2019 KW - Leichte Gesteinskörnungen KW - Bau- und Abbruchabfälle KW - Mauerwerkbruch KW - Recycling PY - 2019 VL - 2019 SP - 89 EP - 94 PB - Otto-von-Guericke-Universität Magdeburg CY - Magdeburg AN - OPUS4-50189 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Buchheim, Janine A1 - Recknagel, Christoph A1 - Wolter, Patrick A1 - Kittler-Packmor, Kai T1 - A new approach towards scientific evaluation and performance-related design of bituminous joint sealing materials and constructions N2 - While there is a permanent improvement of concrete pavement mixtures and pavement construction types over the last decades, the state-of-the-art joint sealing materials and joint constructions seem to stagnate on an antiquated empirical level. This status has been reaffirmed in the latest European standard. The consequences in the motorway network due to unsatisfying capability and durabilty of joint sealing systems are unacceptable. In addition, inadequate traffic performance (noise emissions, roll-over comfort) and traffic safety losses in the joint area of concrete pavements are existing challenges. These deficits and weaknesses reflect a demand for joint sealing materials and constructions whose approval requirements take functional aspects into account. Furthermore a sufficient analysis of decisive loads and a practice-oriented method to evaluate the requirements towards performance and durability is still missed. In this contribution decisive loads to German highways are analyzed. The design of test specimen for representative functional testing of joint sealing systems is discussed. The focus is on the geometry of the test specimens and the used concrete mixture. Finally, a new approach for a function-orientated test concept that considers representative load functions is presented. The potential of this approach to validate the durability and capability of various joint sealing systems is also presented using an example. T2 - RILEM International Symposium on Bituminous Materials CY - Online meeting DA - 08.06.2020 KW - Joint sealing KW - Expansion joint KW - Performance testing KW - Capability KW - Durability PY - 2020 SN - 978-3-030-46454-7 VL - 27 SP - 1 EP - 6 PB - Springer Nature AN - OPUS4-53488 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Recknagel, Christoph T1 - SENSO JOINT - An innovative sensor for suitable joint design N2 - Inacceptable capability and durability of joint sealing systems but also inadequate traffic performance (noise emission; overrolling comfort) up to traffic safety aspects reflect the still enormous demand for data-based description of concrete pavements performance under heavy loading conditions. Especially the deformation behavior of concrete pavement slabs in the joint region in consideration of new pavement construction types and improved concrete mixtures meanwhile established but also under the steeply rising traffic loads is not sufficiently explored. To create a data basis for advanced design rules, evaluation methods and product standards - and with it to improve quality, durability and finally sustainability of pavements - an innovative 3-D sensor system SENSO JOINT adapted to german roadworking requirements and suitable for heavy-duty operating conditions was developed. The contribution introduced describes the development of an extensive technical solution based on the analysis of decisive loads, interactions and boundary conditions. Based on calibration data, results of laboratory testing and finally field-testing on different concrete pavement construction types the outcome of a multi-level evaluation process shall introduce the potential of the new sensor system. T2 - 9th International Conference on Maintenance and Rehabilitation of Pavements (MAIREPAV 2020) CY - Online meeting DA - 01.07.2020 KW - Concrete pavements KW - Sustainable joint sealing KW - Load quantification KW - innovative measurement technology KW - Field validation KW - Performance design for joint systems PY - 2020 AN - OPUS4-51926 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Pirskawetz, Stephan T1 - Richtlinie zur Detektion von Spanndrahtbrüchen mit Schallemissionsanalyse N2 - Ein großer Teil unserer Brücken wurden in den 1950er bis 1970er Jahren als Spannbetonbrücken gebaut. Mit der damals noch relativ jungen Technologie entstanden elegante, teilweise gewagte Bauwerke mit großen Spannweiten, welche die Vorteile der Materialien Stahl und Beton geschickt kombinieren. Die Standsicherheit einiger dieser Brücken ist heute gefährdet. Die Ursachen liegen in der enorm gewachsenen Belastung durch Schwerverkehr, teilweise ungenügender Wartung und in konstruktiven und Materialschwächen, die der mangelnden Erfahrung mit der Technologie in der Bauzeit geschuldet sind. Ein neuralgischer Punkt der Bauwerke sind die in den Beton integrierten Spannglieder. Infolge von Korrosion und Ermüdung können Elemente der Spannglieder reißen, wodurch die für das Tragwerk notwendige Spannung und somit die Tragfähigkeit reduziert werden. Nicht bei allen Brücken kündigen sichtbare Risse im Beton oder auffällige Verformungen den Tragfähigkeitsverlust bzw. das finale Versagen rechtzeitig an. Die Schallemissionsanalyse ist die derzeit einzige Methode, das Reißen einzelner Spannstähle zuverlässig und mit wirtschaftlich vertretbarem Aufwand zu detektieren. Trotzdem es schon einige Spannbetonbauwerke gibt, die mit Schallemissionsanalyse überwacht werden, ist das Verfahren noch wenig bekannt. Außerdem fehlen technische Richtlinien, was die Ausschreibung und Vergabe von entsprechenden Aufträgen und die Bewertung der Angebote sehr erschwert. Um sowohl Baulastträger als auch Dienstleistungsanbieter in den Vergabeverfahren und im Betrieb der Monitoringsysteme zu unterstützen, hat sich eine Gruppe von Experten aus den Bereichen Bauingenieurwesen und Schallemission zum Entwurf einer Richtlinie „Detektion von Spanndrahtbrüchen mit Schallemission“ zusammengefunden. Mit diesem Beitrag wird die Richtlinie vorgestellt, die 2024 erscheinen soll. T2 - Fachtagung Bauwerksdiagnose CY - Berlin DA - 29.02.2024 KW - Spannbeton KW - Brücke KW - Spannstahlbruch KW - Schallemission PY - 2024 AN - OPUS4-59688 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Munsch, Sarah Mandy A1 - Telong, Melissa A1 - Grobla, Lili A1 - Schumacher, Katrin A1 - Völker, Christoph A1 - Yared, Kaleb A1 - Kruschwitz, Sabine ED - Ferrara, Liberato ED - Muciaccia, Giovanni ED - di Summa, Davide T1 - Study on the Predictability of Carbonation Resistance of Cementitous Materials Based on NMR Features and the Use of SLAMD N2 - This study explores the acceleration of material design in the concrete industry, focusing on improving carbonation resistance, a key factor in the durability of concrete structures. Traditional tests for carbonation resistance are lengthy, but with the construction industry aiming for sustainable production, finding a balance between carbonation resistance and CO2 footprint is crucial. Our research employs two innovative methods: 1. Applying the Sequential Learning App for Materials Discovery (SLAMD), an AI materials design framework, to an extensive dataset of real-world concrete compositions to selectively test materials that meet market demands: maximum durability, optimal eco-durability, and the best cost-durability trade-off. 2. Investigating 1H Nuclear Magnetic Resonance (NMR) relaxometry as a quick alternative for characterizing carbonation behavior, as it saves time compared to traditional tests and assesses the complete material’s pore space. Specific NMR features are then integrated into the material design model, with the model’s performance compared against traditional approaches. The results of our study are compelling, demonstrating that materials can be precisely tailored to meet specific requirements with minimal data points. This marks a significant stride in the concrete industry, indicating thatNMR-based, lowfidelity surrogate characterizations, combined with a focused, data-driven design approach, can substantially accelerate the development of durable, sustainable concrete mixtures. T2 - 4 RILEM Spring Convention and Conference on advanced construction materials and processes for a carbon neutral society 2024 CY - Milano, Italy DA - 07.04.2024 KW - Nuclear magnetic resonance KW - carbonation resistance KW - cement and concrete KW - SLAMD app KW - predictability PY - 2024 DO - https://doi.org/10.1007/978-3-031-70281-5_49 VL - 2 SP - 435 EP - 442 PB - Springer CY - Cham, Switzerland AN - OPUS4-61692 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Tyagi, Divyansh T1 - Damage Localisation and Quantification from Experimental Modal Data using Sparsity Promoting Priors N2 - Structural components gradually undergo damage during their service life. This leads to un-desirable Operating Conditions (OCs) such as high stresses, large displacements, etc., which could ultimately lead to their failure. Thus, it is necessary to identify the presence and extent of damage to take appropriate measures for failure mitigation. A computer model of a com-ponent is used to make predictions about the aforementioned OCs under different boundary conditions, thereby serving as a means to forecast failure. However, a data-driven update of the model parameters according to the component’s current damage state is important for it to make reliable predictions. The goal of this work is to perform damage localisation and quantification in the model us-ing modal response data, due to its property of implicitly carrying damage information. As an example, experimental modal data together with its uncertainty bounds from a gradually damaged concrete slab is used. An inverse problem is formulated and solved using Bayesian inference. Damage regions are defined with a spatially varying field corresponding to a reduc-tion in the nominal Young’s modulus over a sub-domain. An arbitrary number of such damage regions are assumed to be present over the domain. The locations of these regions and the local reduction in Young’s modulus within them are then inferred. Sparsity-promoting priors with regard to the number of damage regions are used, which provide the needed regularization for the problem. T2 - FrontUQ 2024 CY - Braunschweig, Germany DA - 24.09.2024 KW - Bayesian Inference KW - Solid Mechanics KW - Sparsity Promoting Priors PY - 2024 AN - OPUS4-61786 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Pirskawetz, Stephan T1 - B1 - Brücke am Altstädter Bahnhof in Brandenburg an der Havel - Detektion von Spanndrahtbrüchen mit Schallemissionsanalyse N2 - Bei einer turnusmäßigen Inspektion der B1 Brücke am Altstädter Bahnhof in Brandenburg an der Havel wurden im Dezember 2019 Risse und Hohlstellen entlang der Längsträger festgestellt. Als Ursache wurde das Versagen eines signifikanten Anteils der Spanndrähte der konzentrierten Spannglieder vermutet. Die Brücke wurde umgehend für den Verkehr gesperrt und nach weiteren, umfassenden Untersuchungen im Mai 2021 abgebrochen. Um die Sicherheit des unter der Brücke geführten Verkehrs zu gewährleisten, wurde die Brücke unter anderem mit einem Schallemissionsmesssystem überwacht. Mit diesem Verfahren ist es möglich, Spanndrahtbrüche zuverlässig zu detektieren und zu lokalisieren. In dem gut einjährigen Überwachungszeitraum wurden mehr als einhundert Spanndrahtbrüche detektiert, die in einigen Bereichen der Brücke besonders konzentriert auftraten. Vor dem Abbruch der Brücke war es möglich, den Nachweis der Detektion von Spanndrahtbrüchen mit der Schallemissionsanalyse und ihre Ortungsgenauigkeit anhand von künstlich erzeugten Drahtbrüchen zu validieren. Weiterhin konnte das sichtbare Schadensbild, Längsrisse und Hohlstellen über den Spannkanälen, auf die lokale Schädigung der Spanndrähte zurückgeführt werden. Derzeit wird ein Merkblatt erarbeitet, in dem die Erfahrungen in der bisherigen Anwendung der Schallemissionsanalyse zum Monitoring von Spanndrahtbrüchen zusammengefasst werden. In diesem Beitrag werden die Grundlagen der Schallemissionsanalyse und die Ergebnisse der Validierungsversuche an der Brücke in Brandenburg dargestellt. Weiterhin werden die Vorteile und Grenzen der Brückenüberwachung mittels Schallemissionsanalyse sowie Maßnahmen zur Sicherstellung der Qualität und der Zuverlässigkeit diskutiert. T2 - 5. Brückenkolloquium CY - Esslingen, Germany DA - 05.09.2022 KW - Spannbetonbrücke KW - Spannstahlbruch KW - Schallemission KW - Fotogrammetrie KW - Faseroptik PY - 2022 AN - OPUS4-55686 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Wolf, Christoph T1 - Optimization Framework for Powder Bed 3D Printed Concrete Structures under Various Constraints N2 - The fusion of 3D printing with concrete has transformed large scale construction, accelerating creative design possibilities. In recent years, multiple printing techniques have been developed and are still under investigation. The powder bed technique enables overhang constructions, thereby increasing design flexibility. To maximize the advantages of those printing techniques, a holistic approach is required taking topology optimization through finite element analysis into account. The challenge is to consider a range of constraints, from material to geometrical to manufacturing. The current research focuses on the development of a holistic approach to large-scale 3D powder bed printed concrete structure optimization, navigating the in-tricacies of constraints, leveraging the advantages of powder-based printers, and integrating essential information from material tests. A workflow starting from geometry input and ending with printing instructions is derived, minimizing user interaction, and offering fast and reliable results for different structures. Starting from a geometric model of the global design with the required load cases, the geometry is optimized with respect to reduce the mass and thus CO2 emissions. Thereby, the topology optimization includes various constraints: stress con-straints (mitigating tension and limit compressive stress using Drucker-Prager based models), geometric constraints (preserving specific surfaces from optimi-zation), and manufacturing constraints (controlling member size and avoiding trapped powder). Different objective functions, like minimizing compliance or mass are considered in this study. The process receives input from upstream ma-terial tests, offering insights into strength, stiffness and possible anisotropy. This integration of material testing enhances the accuracy and reliability of the opti-mization, aligning the design with real-world behavior of 3D printed concrete. An important aspect of the workflow is the segmentation of the optimized global structure into substructures, aligning with the size limitations of the 3D powder-bed printer. As final output of the developed workflow, printer specific fabrica-tion instructions are generated for each substructure. The developed optimization framework is demonstrated in the design of a multiperson shading element. T2 - 4th RILEM International Conference on Concrete and Digital Fabrication CY - Munich, Germany DA - 04.09.2024 KW - Topology Optimization KW - Powder Bed 3D Printing KW - Segmentation and Substructure KW - Modelling KW - Material Testing PY - 2024 AN - OPUS4-61021 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Diercks, Philipp T1 - Multiscale modeling of heterogeneous structures based on a localized model order reduction approach N2 - Many of today’s problems in engineering demand reliable and accurate prediction of failure mechanisms of mechanical structures. Thus, it is necessary to take into account the heterogeneous structure on the smaller scale, to capture the underlying physical phenomena. However, this poses a great challenge to the numerical solution since the computational cost is significantly increased by resolving the smaller scale in the model. Moreover, in applications where scale separation as the basis of classical homogenization schemes does not hold, the influence of the smaller scale on the larger scale has to be modelled directly. This work aims to develop an efficient concurrent methodology to model heterogeneous structures combining the variational multiscale method (VMM) [1] and model order reduction techniques (e. g. [2]). First, the influence of the smaller scale on the larger scale can be taken into account following the additive split of the displacement field as in the VMM. Here, also a decomposition of the global domain into subdomains, each containing a fine grid discretization of the smaller scale, is introduced. Second, local reduced approximation spaces for the smaller scale solution are constructed by exploring possible solutions for each subdomain based on the concept of oversampling [3]. The associated transfer operator is approximated by random sampling [4]. Herein, we propose to incorporate the actual physical behaviour of the structure of interest in the training data by drawing random samples from a multivariate normal distribution with the solution of a reduced global problem as mean. The local reduced spaces are designed such that local contributions of each subdomain can be coupled in a conforming way. Thus, the resulting global system is sparse and reduced in size compared to the direct numerical simulation, leading to a faster solution of the problem. T2 - ECCOMAS YIC CY - Porto, Portugal DA - 19.06.2023 KW - Multiscale Method KW - Variational Multiscale Method KW - Domain Decomposition KW - Model Order Reduction PY - 2023 AN - OPUS4-58251 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Neugum, Tim T1 - Feuerwiderstand gezwängter Stahlbetonstützen N2 - Bei realen Brandereignissen stellen sich in der Regel mechanische und thermische Randbedingungen ein, die deutlich von denen in präskriptiven, bauteilorientierten Brandprüfungen abweichen. Beispielsweise werden Interaktionen der brandbeanspruchten Bauteile mit dem umgebenden Tragwerk und daraus resultierende Zwangsbeanspruchungen bei konventionellen Brandprüfungen nicht berücksichtigt. Mit Hilfe der Substrukturtechnik kann das Verhalten einer Stütze im Brandfall unter Berücksichtigung der Interaktion mit dem umgebenden Tragwerk untersucht werden. T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM CY - Berlin, Germany DA - 16.10.2024 KW - Substrukturtechnik KW - Stahlbeton KW - Stützen KW - Zwang KW - Brandschutz PY - 2024 AN - OPUS4-61402 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bartels, Jan-Hauke A1 - Gündogdu, Berk A1 - Herrmann, Ralf A1 - Marx, Steffen T1 - Beschleunigungssensoren zur Zustandsüberwachung von Ingenieurbauwerken unter Einfluss von Umweltfaktoren bei tiefen Frequenzen T1 - Acceleration sensors for structural health monitoring of engineering structures under the influence of environmental factors at low frequencies N2 - Structural Health Monitoring (SHM) wird zunehmend zur kontinuierlichen Zustandsbewertung von Ingenieurbauwerken eingesetzt. Wichtige Bewertungsparameter sind globale Systemeigenschaften, wie z. B. Eigenfrequenzen, zu deren Bestimmung Beschleunigungssensoren eingesetzt werden. Häufig werden sog. MEMS-Sensoren (Micro Electro Mechanical Systems) verwendet, die jedoch ein hohes Rauschniveau aufweisen. Alternativ können rauschärmere IEPE-Sensoren (Integrated Electronics Piezo Electric) eingesetzt werden, die auch bei geringster Strukturanregung Schwingungen zuverlässig erfassen. Ferner besteht das Problem, dass Änderungen der Eigenfrequenzen infolge Bauwerksschädigung schwer von Änderungen der Eigenfrequenzen infolge Umwelteinflüssen zu unterscheiden sind. Letztere verändern die Eigenschaften der Struktur und die des Messsystems. Um Umwelteinflüsse auf das Messsystem im Anwendungsgebiet Ingenieurbau zu untersuchen, wurden IEPE-Beschleunigungsaufnehmer hinsichtlich ihres Übertragungsverhaltens im niederfrequenten Beschleunigungsbereich analysiert. Es zeigt sich, dass das Verhalten nicht nur frequenz-, sondern auch temperaturabhängig ist, während die Luftfeuchte keinen Einfluss hat. Diese für das Bauwerk unbedenklichen Einflüsse müssen für eine robuste Zustandsüberwachung kompensiert werden. Für die Anwendung im Ingenieurbau werden IEPE-Sensoren empfohlen, da sie ein hohes Signal-zu-Rausch-Verhältnis aufweisen und niederfrequente Bauwerksschwingungen zuverlässig erfassen. N2 - Acceleration sensors for structural health monitoring of engineering structures under the influence of environmental factors at low frequencies. Structural health monitoring (SHM) is increasingly used to continuously assess the condition of engineering structures. Important assessment parameters are global system properties, such as eigenfrequency, which are measured by accelerometers. Micro-electro-mechanical systems (MEMS) sensors are often used, but have a high noise level. Alternatively, low-noise IEPE (integrated electronics piezo electric) sensors can be used, which reliably detect vibrations even with the slightest structural excitation. Another problem is that changes in eigenfrequency due to structural damage are difficult to distinguish from changes in eigenfrequency due to environmental effects. The latter change the properties of both the structure and the measurement system. In order to investigate environmental effects on the measurement system in the field of civil engineering, IEPE accelerometers have been analyzed for their transmission behavior in the low-frequency acceleration range. It was found that the behavior is not only frequency dependent, but also temperature dependent, while humidity has no influence. These nonstructural effects must be compensated for to ensure robust condition monitoring. IEPE sensors are recommended for civil engineering applications because of their high signal-to-noise ratio and ability to reliably detect low-frequency structural vibrations. KW - Beschleunigungssensoren KW - Kalibrierung KW - Structural Health Monitoring KW - Umwelteinflüsse KW - Übertragungsverhalten KW - acceleration sensors KW - calibration KW - environmental influences KW - transmission behavior PY - 2024 DO - https://doi.org/10.1002/bate.202300056 SN - 1437-0999 SN - 0932-8351 VL - 101 IS - 10 SP - 1 EP - 11 PB - Ernst & Sohn CY - Berlin AN - OPUS4-60772 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Weise, Frank A1 - Fladt, Matthias T1 - Innenhydrophobierung - neuartige AKR-Vermeidungsstrategie bei Betonfahrbahndecken N2 - Verstärkt auftretende Schäden in Betonfahrbahndecken des Bundesfernstraßennetzes, die mit einer Alkali-Kieselsäure-Reaktion (AKR) in Verbindung gebracht werden, haben zu einer massiven Verschärfung der Prüfvorschriften zur Bewertung der Alkaliempfindlichkeit von Ge-steinskörnungen geführt. Die damit verbundene Einschränkung potenziell für den Straßenbau einsetzbarer Gesteinskörnungen ruft eine verstärkte Ressourcenknappheit und ein erhöhtes Transport- und damit einhergehendes Kostenaufkommen hervor. Vor diesem Hintergrund wird nach neuartigen AKR-Vermeidungsstrategien gesucht, die auch eine Verwendung grenzwertig alkaliempfindlich eingestufter Gesteinskörnungen erlaubt. Einen möglichen Lösungsansatz stellt in diesem Kontext die Innenhydrophobierung des Fahrbahndeckenbetons dar. Es soll so durch die Behinderung des Feuchte- und Tausalzeintrags in den Beton der AKR-Schädigungs-prozess signifikant vermindert werden. Für die Bewertung der Leistungsfähigkeit der Innen-hydrophobierung zur Vermeidung einer schädigenden AKR in Betonfahrbahndecken wird zur-zeit im Auftrage der BASt an der BAM ein Forschungsvorhaben bearbeitet. Im Rahmen dieses Beitrags werden erste ausgewählte Ergebnisse dieses Forschungsvorhabens vorgestellt. So wird exemplarisch an einem Oberbeton (0/8) mit einer alkaliempfindlichen Gesteinskörnung der Einfluss eines Hydrophobierungsmittels auf die Frisch- und Festbetoneigenschaften ganz-heitlich aufgezeigt und bewertet. Bei Letzteren stehen zunächst die mechanischen und hygri-schen Parameter sowie der Frost-Tausalzwiderstand im Vordergrund. In einem weiteren Schritt wird der Einfluss der Innenhydrophobierung auf die schädigende AKR mittels verschie-denartiger AKR-Performanceprüfungen beleuchtet. T2 - Betonstraßentagung 2019 CY - Aschaffenburg, Germany DA - 26.09.2019 KW - Alkali-Kieselsäure-Reaktion KW - AKR KW - Innenhydrophobierung PY - 2019 SN - 978-3-86446-260-3 SP - 1 EP - 15 AN - OPUS4-49484 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Neugum, Tim A1 - Stelzner, Ludwig A1 - Häßler, Dustin A1 - Hothan, Sascha A1 - Zehfuß, J. T1 - Feuerwiderstand gezwängter Stahlbetonstützen N2 - Bei realen Brandereignissen stellen sich in der Regel mechanische und thermische Randbedingungen ein, die deutlich von denen in präskriptiven, bauteilorientierten Brandprüfungen abweichen. Beispielsweise werden Interaktionen der brandbeanspruchten Bauteile mit dem umgebenden Tragwerk und daraus resultierende Zwangsbeanspruchungen bei konventionellen Brandprüfungen nicht berücksichtigt. Mit Hilfe der Substrukturtechnik kann das Verhalten einer Stütze im Brandfall unter Berücksichtigung der Interaktion mit dem umgebenden Tragwerk untersucht werden. T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM CY - Berlin, Germany DA - 16.10.2024 KW - Substrukturtechnik KW - Stahlbeton KW - Stützen KW - Zwang KW - Brandschutz PY - 2024 SN - 978-3-9818564-7-7 SP - 270 EP - 277 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-61401 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Neugum, Tim A1 - Stelzner, Ludwig A1 - Häßler, Dustin A1 - Hothan, Sascha A1 - Zehfuß, J. T1 - Anwendung der Substrukturtechnik zur Untersuchung des Feuerwiderstands von Stützen unter Zwang N2 - Bei realen Brandereignissen stellen sich in der Regel mechanische und thermische Randbedingungen ein, die deutlich von denen in präskriptiven, bauteilorientierten Brandprüfungen abweichen. Beispielsweise werden Interaktionen der brandbeanspruchten Bauteile mit dem umgebenden Tragwerk und daraus resultierende Zwangsbeanspruchungen bei konventionellen Brandprüfungen nicht berücksichtigt. Mit Hilfe der Substrukturtechnik kann das Verhalten einer Stütze im Brandfall unter Berücksichtigung der Interaktion mit dem umgebenden Tragwerk untersucht werden. T2 - Symposium Heißbemessung 2024 CY - Braunschweig, Germany DA - 24.09.2024 KW - Substrukturtechnik KW - Stahlbeton KW - Stützen KW - Zwang KW - Brandschutz PY - 2024 SP - 40 EP - 60 PB - TU Braunschweig CY - Braunschweig AN - OPUS4-61234 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Fladt, Matthias T1 - Internal water-repellent treatment - a novel strategy for mitigating alkali-aggregate reaction in concrete road pavements N2 - To prevent future alkali-aggregate reaction (AAR) damage, which has occurred frequently in the German highway network in recent years, a new regulation has been drafted. This regulation severely limits the use of alkali-sensitive aggregates by requiring that their suitability be verified by certified inspectors using newly developed AAR concrete tests that involve the external supply of alkali. This has led to a significant limitation in the number of aggregates usable for concrete pavements. A novel AAR avoidance strategy is now being pursued, which aims to enable the use of borderline alkali-sensitive aggregates through the application of an internal water-repellent treatment. The addition of water repellents during concrete production should significantly reduce the ingress of water and external de-icing salts into the concrete pavement, thus reducing the potential for AAR damage. This paper presents the results of laboratory tests to assess the suitability of this new AAR prevention strategy. Representative, highly AAR-susceptible road paving concrete made with an alkali-sensitive greywacke and various water repellents were used as the basis for these experiments. The tests for concrete suitability included determining the conventional fresh and hardened concrete properties as well as concrete prism tests with external alkaline supply. Building on these results, laser-induced breakdown spectroscopy (LIBS) analyses of de-icing-salt intrusion as well as microscopic examinations for verification of the AAR characteristics were carried out. The results of the AAR concrete tests with external alkaline supply support the conclusion that, when hydrophobic agents containing a suitable active ingredient are used, the AAR damage process in road paving concrete can be sufficiently prevented. T2 - 16th International Conference on Alkali-Aggregate Reaction in Concrete CY - Lisbon, Portugal DA - 31.05.2022 KW - Concrete pavements KW - Internal water-repellent treatment KW - Preventive measures KW - Testing for potential alkali-aggregate reaction PY - 2022 AN - OPUS4-55185 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Neugum, Tim T1 - Anwendung der Substrukturtechnik zur Untersuchung des Feuerwiderstands von Stützen unter Zwang N2 - Bei realen Brandereignissen stellen sich in der Regel mechanische und thermische Randbedingungen ein, die deutlich von denen in präskriptiven, bauteilorientierten Brandprüfungen abweichen. Beispielsweise werden Interaktionen der brandbeanspruchten Bauteile mit dem umgebenden Tragwerk und daraus resultierende Zwangsbeanspruchungen bei konventionellen Brandprüfungen nicht berücksichtigt. Mit Hilfe der Substrukturtechnik kann das Verhalten einer Stütze im Brandfall unter Berücksichtigung der Interaktion mit dem umgebenden Tragwerk untersucht werden. T2 - Symposium Heißbemessung 2024 CY - Braunschweig, Germany DA - 24.09.2024 KW - Substrukturtechnik KW - Stahlbeton KW - Stützen KW - Zwang KW - Brandschutz PY - 2024 AN - OPUS4-61232 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Pittrich, Tim T1 - Fire-induced spalling of normal strength concrete with different types of blended Portland cement N2 - The cement industry is looking to reduce its overall CO2 footprint. Greener manufacturing can be achieved by the introduction of more clinker-reduced cements. Concrete exposed to fire tends to show explosive spalling caused by thermomechanical and thermohydraulic processes. It is therefore essential to determine how concretes with clinker-reduced cements behave under fire exposure, especially for concretes containing calcined clays, as these are expected to be the supplementary cementitious material of the future. In this paper, normal strength concretes with four different cements (CEM I, CEM II/A-LL, CEM III/A and CEM II/B-Q) were examined for their fire-induced spalling behaviour. In addition, a mix with PP fibres was investigated for each concrete. The experiments were conducted on ring-restrained cylindrical specimens exposed to the hydrocarbon fire curve. The results showed that the cement type influences spalling behaviour. Samples with CEM I spalled the least, followed by CEM II/A-LL and CEM III/A. Finally, samples with CEM II/B-Q showed the most severe damage. It was found that the spalling behaviour of different concretes correlates with the moisture content before exposure to fire, meaning that higher moisture content leads to higher spalling susceptibility. The use of 2 kg/m³ PP fibres completely inhibited spalling regardless of the cement type used and therefore remains a successful avoidance strategy. T2 - Structures in Fire 2024 CY - Coimbra, Portugal DA - 19.06.2024 KW - Fire-induced concrete spalling KW - Normal strength concrete KW - Blended Portland cement KW - SCM KW - PP-fibres PY - 2024 AN - OPUS4-60521 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Pittrich, Tim T1 - Tunnelbrand – Abplatzverhalten von normalfesten Betonen mit verschiedenen klinkereffizienten Zementen N2 - Zur Verminderung der CO2-Emissionen der Bauindustrie gewinnen klinkereffiziente Zemente immer mehr an Bedeutung und werden vermehrt in Ingenieurbauwerken eingesetzt. Das brandinduzierte Abplatzverhalten von Betonen mit diesen Zementen ist allerdings nur bedingt bekannt und ist u.a. im Tunnelbau von hoher Bedeutung. Im Zuge dessen, wurden normalfeste Betone mit vier verschiedenen Zementen (CEM I, CEM II/A-LL, CEM III/A und CEM II/B-Q) auf ihr brandinduziertes Abplatzverhalten untersucht. Die Ergebnisse zeigen, dass Betone mit klinkereffizienten Zementen zu stärkeren Abplatzungen neigen. T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM Green Intelligent Building CY - Berlin, Germany DA - 16.10.2024 KW - Beton KW - Brandinduziertes Abplatzen KW - Klinkereffiziente Zemente KW - PP-Fasern PY - 2024 AN - OPUS4-61414 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Barthel, Maria A1 - Rübner, Katrin A1 - Kühne, Hans-Carsten T1 - Aktivierung von Papierasche zur Nutzung als Bindemittelkomponente N2 - In Deutschland fallen jährlich 20 Millionen Tonnen Altpapier an. 75 % davon werden dem Recyclingprozess zugeführt. Dabei bleiben Prozessrückstände wie Deinkingschlämme, Sortierrückstände und Faserreststoffe übrig. Zusammengefasst als Papierschlamm verwerten die Recycler diesen Reststoff thermisch in dezentralen Heizkraftwerken. Die dabei anfallende Papierasche hat mit den Anteilen der Hauptoxide von 59 M.-% CaO, 22 M.-% SiO2 und 13 M.-% Al2O3 eine ähnliche chemische Zusammensetzung wie Portlandzement, wobei sich die Mineralphasen unterscheiden. Durch eine Aktivierung der Papierasche können jedoch hydraulisch aktive Phasen wie Mayenit (C7A12) und Belit (C2S) erzeugt werden. Die Mineralphase Mayenit reagiert schnell mit Wasser zu Calciumaluminathydraten, wodurch der Bindemittelleim schnell ansteift. Die festigkeitsbildenden Calciumsilicathydrate (CSH) in Bindemittelleimen entstehen bei einer späteren Reaktion von Belit mit Wasser. Zur Aktivierung dient eine hydrothermale Calcinierung. Dabei wird Papierasche mit einer Aktivatorlösung (Wasser oder KOH) gemischt und bei 200 °C hydrothermal behandelt, wobei sich Hydratphasen ausbilden. Diese Zwischenprodukte dehydratisieren durch eine anschließende Calcinierung zu reaktiven Calciumsilicaten und Calciumaluminaten. Wie sich die Parameter des Aktivierungsprozesses auf die Mineralphasen auswirken, war Fokus der Untersuchungen. Mit thermogravimetrischen Analysen der Zwischenprodukte konnten die Reaktionsprodukte nach dem hydrothermalen Prozessschritt bestimmt werden. Den größten Einfluss auf den Mineralphasenbestand hat hierbei die Alkalität der Aktivatorlösung. Im zweiten Prozessschritt, der Calcinierung, ist die Temperatur der wesentliche Faktor für die Ausbildung reaktiver Phasen. Die Ergebnisse kalorimetrischer Untersuchungen an Leimen aus den calcinierten Proben dienten der Auswahl der optimalen Calcinierungstemperatur. Die gesamte Reaktionswärme war für die Proben, welche bei einer Calcinierungstemperatur zwischen 700-800 °C hergestellt wurden, am höchsten. T2 - GDCH-Tagung Bauchemie CY - Aachen, Germany DA - 30.09.2019 KW - Papierasche KW - Zement KW - Hydrothermale Calcinierung KW - Bindemittel PY - 2019 SN - 978-3-947197-13-2 VL - 54 SP - 16 EP - 24 CY - Aachen AN - OPUS4-49312 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kühnel, Alena T1 - Measurement and analysis of concrete pavement surface textures using hand-held 3d laser scanning technology N2 - Concrete pavement surface textures are divided by means of their dimension into four categories: microtexture, macrotexture, megatexture and roughness. They influence the most important performance characteristics of road surfaces, such as friction (also referred to as “skid resistance”), tire/pavement noise, evenness and surface drainage. These properties are relevant for driving safety, comfort and environmental aspects. Up to now, research in Germany has focused on monitoring these characteristics by tire/pavement noise and skid resistance measurements. However, the topography of surface textures has not been sufficiently investigated and evaluated until now. The development and availability of high-performance, hand-held 3D scanning systems during the last years enable measurements of the microtexture and macrotexture of concrete pavement surfaces at short measuring times and high resolution. This paper shows the ability of modern laser-based technology to record three-dimensional data of different concrete pavement surface textures in situ. For this purpose, a special measuring frame has been developed. The presented results were primarily obtained within the framework of a research project commissioned by the German Federal Highway Research Institute (BASt) and processed by the Federal Institute for Materials Research and Testing. Various concrete pavement surface textures by means of diamond grinding and hybrid of diamond grinding and grooving were investigated in situ. In addition, exposed aggregate concretes (EAC), which were introduced as a standard type of concrete for motorway pavements in Germany in 2006, have been analyzed. Based on the gathered 3D data, evaluation routines for qualitative and quantitative analysis have been developed and applied. The aim was to derive the statistical parameters such as the relative and cumulative frequency distribution of the profile depth as well as the roughness coefficient for diamond ground pavements and EAC. Also, the “mean profile depth” (MPD) as a common texture-related parameter was determined. T2 - 14th International Symposium on Concrete Roads CY - Krakow, Poland DA - 25.06.2023 KW - Concrete pavement surface textures KW - 3D laser scanning KW - Diamond grinding KW - Hybrid of diamond grinding and grooving KW - Exposed aggregate concrete surface KW - Surface characteristics KW - Data analysis PY - 2023 AN - OPUS4-60965 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Gebauer, D. A1 - Beltrán Gutierrez, R. A1 - Marx, S. A1 - Maack, Stefan A1 - Küttenbaum, Stefan A1 - Pirskawetz, Stephan A1 - Breit, W. A1 - Mechtcherine, V. A1 - Grahl, K. A1 - Thiel, T. A1 - Schickert, M. A1 - Krüger, M. T1 - Interrelated Data Set from Nondestructive and Destructive Material Testing of Concrete Compressive Strength Specimens N2 - "This data set contains three different data types obtained from concrete specimens. For each specimen, the rebound numbers, ultrasonic data (ultrasonic velocity, time of flight), and destructive concrete strength are given. Two kind of specimen geometries were tested: cubes and drilled cores. The files are labeled according to the specimen geometry as "cube" or "core" and the type of measurement data as "compressive_strength", "rn_R" and "rn_Q" for rebound numbers as well as "us" for ultrasonic data. The ultrasonic data were generated by six independent laboratories, the rebound numbers by five independent laboratories and the destructive tests by one laboratory. The designation of each specimen establishes the relationship between the different data types." KW - Compressive Concrete Strength KW - Rebound Hammer KW - Ultrasonic Pulse Velocity PY - 2023 DO - https://doi.org/10.7910/DVN/AFCITK PB - Harvard College CY - Cambridge, MA, USA AN - OPUS4-57223 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Thiele, Marc A1 - Makris, Ralf ED - Aign, J. T1 - Reinforcement bar and reinforcement bar splicing systems under impact loading – Experimental tests and test specification N2 - Reinforced concrete is a widely used material for power generation structures, where load scenarios like impact loadings need to be considered. In this context mechanical splicing systems for the connection of reinforcement bars are of specific interest and impact resistance for the splicing systems has to be verified. High speed tensile tests need to be performed on splicing systems for reinforcement bars to confirm the capability of the coupler to resist impact loading. Furthermore, the ability of the reinforcement steel to dissipate energy by ductile behaviour with pronounced plastic strains should be confirmed by these tests. During the last decades comprehensive experiences were developed at BAM performing high speed tensile tests on reinforcement bars as well as on several splicing systems. For the lack of available standards defining these tests in detail an appropriate test procedure was developed and continuously optimized during this period at BAM. The test procedure is partially based on testing principles adapted from available standards. The main intention behind this test procedure is to perform high-speed tensile tests with a specific constant strain rate generated at the specimen. Furthermore, main objective was to establish a procedure to guarantee the comparability of test results for different diameter of reinforcement as well as for different types of couplers. Besides the pure execution of the high-speed tensile tests, the test specification also declares how to evaluate the measurements and the test results. Finally, some typical results will be presented in this contribution. T2 - SMIRT 26 CY - Potsdam, Germany DA - 10.07.2022 KW - Impact KW - Coupler systems KW - High-speed KW - Reinforcement PY - 2022 SP - 1 EP - 10 AN - OPUS4-55422 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Robens-Radermacher, Annika T1 - Efficient model identification using a PGD forward model - Influence of surrogate accuracy and converergence approach N2 - There is a rising attention of using numerical models for effcient structural monitoring and ensuring the structure's safety. Setting up virtual models as twin for real structures requires a model identification process calculating the unknown model parameters, which mostly are only indirectly measurable. This is a computationally very costly inverse optimization process, which often makes it unfeasible for real applications. Effcient surrogate models such as reduced order models can be used, to overcome this limitation. But the influence of the model accuracy on the identification process has then to be considered. The aim is to automatically control the influence of the model's accuracy on the identification. Here, a variational Bayesian inference approach[3] is coupled with a reduced forward model using the Proper Generalized Decomposition (PGD) method. The influence of the model accuracy on the inference result is studied and measured. Therefore, besides the commonly used Bayes factor the Kullback-Leibler divergences between the predicted posterior pdfs are proposed. In an adaptive inference procedure, the surrogate's accuracy is iteratively increased, and the convergence of the posterior pdf is analysed. The proposed adaptive identification process is applied to the identification of spatially distributed damage modeled by a random eld for a simple example with synthetic data as well as a small, reinforced bridge with real measurement data. It is shown that the proposed criteria can mirror the influence of the model accuracy and can be used to automatically select a suffciently accurate surrogate model. T2 - The 8th European Congress on Computational Methods in Applied Sciences and Engineering (ECCOMAS) 2022 CY - Oslo, Norway DA - 05.06.2022 KW - Model order reduction KW - Model identification KW - Bayes factor KW - PGD KW - Kullback-Leibner divergence PY - 2022 AN - OPUS4-55112 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Robens-Radermacher, Annika T1 - Stiffness identification by efficient model calibration of random field variables for the Young's modulus N2 - The main challenge in using numerical models as digital twins in real applications for prognosis purposes, such as reliability analysis, is the calibration and validation of the models based on uncertain measurement data. Uncertainties are not limited to the measurement data, but the numerical model itself will not be perfect due to the modelling assumptions. In this contribution, a probabilistic inference method for model calibration, based on the Bayes’ Theorem, is used to face that issue. Such inference approaches include uncertainties on the data as well as on the model parameters, allowing to compute an a posteriori distribution for the model parameters as well as a noise term reflecting the measured data. However, such probabilistic inference methods require a lot of evaluations of the numerical forward model for different model parameters. An improvement of the efficiency is obtained by replacing the forward model with a reduced model. Model reduction, e.g. the proper generalized decomposition (PGD) method, is a popular concept to decrease the computational effort, where each evaluation of the reduced forward model is a pure less costly function evaluation. The heterogeneous spatial distribution of material parameters in the forward model is described by a lognormal random field. This allows identifying a variable stiffness over the spatial directions by identifying the random field variables with given measurement data. These changes can e.g. be caused by damage. The lognormal field is approximated as series expansion for the PGD problem. The derived efficient model identification procedure is shown using a real reinforced prestress demonstrator bridge and stereophotogrammetry measurement data. A digital twin for that demonstrator bridge is build up using a set of measurement data and verified by testing additional measurement data. PGD model error against the FEM model is discussed based on an importance sampling analysis computing the Bayes Factor. T2 - COMPLAS 2021 CY - Berlin, Germany DA - 08.09.2021 KW - Digital twin KW - Structure monitoring KW - Model updating KW - Proper generalized decomposition KW - Bayesian inferences PY - 2021 AN - OPUS4-53285 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Robens-Radermacher, Annika T1 - Modeling the influence of temperature for extrusion based 3d concrete printing from material to structural stability N2 - Abstract: 3D concrete printing (3DCP) aims to revolutionize construction by increasing automation, reducing material usage, and enabling customized designs. Despite its potential, the lack of regulations and reliance on trial-and-error methods result in significant waste and inefficiencies. Reliable models are needed to predict and control the complex printing process with its various influencing factors from material, process, and environment. This study aims to develop a structural model to predict print stability and prevent buckling and material failure in extrusion-based 3D concrete printing (3DCP), with a focus on environmental influences, particularly temperature. The structural build-up of the material is crucial for stability but is influenced by material ingredients, water-binder ratio, and ambient conditions, which vary in real-world projects. It describes the process of cementitious material gaining strength and stability during its early ages due to thixotropy and early hydration. Modeling that, a time- and temperature-dependent model for the evolution of early-age material parameters, such as stiffness, is derived. The model employs the maturity method, using an equivalent time to capture the temperature influence. It is verified using experimental data on stiffness evolution from squeeze flow tests and yield stress evolution measured from rotational rheometer tests. The model parameters are estimated using Bayesian inference, and validation shows good agreement with experimental data for both parameters at the material level. Subsequently, the derived time- and temperature-dependent stiffness model is adapted into a structural simulation using an elastoplastic material law with nonlinear hardening to study the temperature effect on the stability of 3DCP. Layers are activated sequentially based on a pseudo-density approach. The method is illustrated with an example of a printed wall with a width of one layer under varying ambient temperatures. The temperature impact on buckling and material failure during printing is demonstrated and numerically investigated through a sensitivity study. T2 - 95 th Annual Meeting of the International Association of Applied Mathematics and Mechanics (GAMM) CY - Poznan, Poland DA - 07.04.2025 KW - 3D concrete printing KW - Structural build-up KW - Temperature KW - Maturity method KW - Structural simulation PY - 2025 AN - OPUS4-62966 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Robens-Radermacher, Annika T1 - Advantages and challenges of data stores for interlaboratory studies – an example from mechanical test data of printed concrete structures N2 - Interlaboratory studies are common tools for collecting comparable data to implement standards for new materials or testing technologies. In the case of construction materials, these studies form the basis for recommendations and design codes. Depending on the study, the amount of data collected can be enormous, making manual handling and evaluation difficult. On the other hand, the importance of the FAIR (findable, accessible, interoperable, and reusable) principles for scientific data management, published by Wilkinson et al. in 2016, is constantly growing and changing the view on data usage. The benefits of using data management tools such as data stores/repositories or electronic laboratory notebooks are many. Data is stored in a structured and accessible way (at least within a group) and data loss due to staff turnover is reduced. Tools usually support data publishing and analysis interfaces. In this way, data can be reused years later to generate new knowledge with future insights. On the other hand, there are many challenges in setting up a data repository, such as selecting suitable software tools, defining the data structure, enabling data access, and understanding by others and ensuring maintenance, among others. This talk discusses the advantages and challenges of setting up and applying a data repository using the interlaboratory study on the mechanical properties of printed concrete structures carried out in RILEM TC 304-ADC as example. First, the definition of a suitable data structure including all information is discussed. The tool-dependent upload process is then described. Here, the data management system openBIS (open source software developed by ETH Zurich) is used. Since in most cases an open compute platform allowing access from different organisations is not possible or available due to data protection and maintenance issues, tool-independent export options are discussed and compared. Finally, the different query and analysis possibilities are demonstrated. T2 - RILEM spring convention & conference on advanced construction materials and processes for a carbon neutral society 2024 CY - Milan, Italy DA - 07.04.2024 KW - Data stores KW - Data structuring KW - Data evaluation KW - Automatization KW - Interlaboratory PY - 2024 UR - https://www.rilem.net/agenda/rilem-spring-convention-conference-on-advanced-construction-materials-and-processes-for-a-carbon-neutral-society-1530 AN - OPUS4-59906 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Robens-Radermacher, Annika T1 - Modellierung und Simulation von 3D Betondruck – Design- und Prozessoptimierung N2 - Der 3D Betondruck ermöglicht die effiziente und ressourcenschonendere Herstellung maßgeschneiderter Betonstrukturen. Trotz des großen Potentials gibt es bisher keine einheitlichen Normen und Standards für den sicheren und robusten 3D Betondruck. Der Beitrag zeigt das Potential numerischer Methoden und Modelle zur effizienten und ressourcenschonenden Design- und Prozessoptimierung des 3D Betondrucks. Dazu werden die aktuellen Forschungsarbeiten im Bereich der Entwicklung robuster und zuverlässiger numerischer Zwillinge, geeigneter Optimierungstools sowie digitaler Workflows diskutiert. T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM Green Intelligent Building CY - Berlin, Germany DA - 16.10.2024 KW - 3D Betondruck KW - Design- und Prozessoptimierung KW - Modellierung KW - Simulation PY - 2024 AN - OPUS4-61575 LA - mul AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Pirskawetz, Stephan A1 - Bösche, Thomas A1 - Carstens, Ole A1 - Hille, Falk A1 - Holst, Ralph A1 - Käding, Max A1 - Kaplan, Felix A1 - Löhr, Manuel A1 - Richter, Walter A1 - Saloga, Katrin A1 - Schmidt, Sebastian A1 - Sodeikat, Christian A1 - Thenikl, Thomas T1 - Detektion von Spanndrahtbrüchen mit Schallemissionsanalyse N2 - Dieses Dokument beschreibt das Verfahren Schallemissionsanalyse zur Detektion von Spanndrahtbrüchen in Spannbetonbrücken im Rahmen einer kontinuierlichen Überwachung. Die Überwachung mit Schallemission liefert eine Aussage über die Anzahl von Spanndrahtbrüchen innerhalb des Überwachungszeitraumes und innerhalb der Reichweite der installierten Sensoren. Mit dem Verfahren können die Spanndrahtbrüche lokalisiert werden. Auf Basis einer weitgehend automatisierten Datenanalyse stehen Informationen über Drahtbrüche kurzfristig nach dem Ereignis zur Verfügung. Der Anwendungsbereich des Dokuments umfasst Brücken- und Ingenieurbauwerke mit Spanndrähten mit sofortigem oder nachträglichem Verbund. Spannsysteme ohne Verbund fallen nicht in den Anwendungsbereich. Die beschriebenen Verfahren können auf Spannsysteme ohne Verbund übertragen werden. Mit dem Verfahren Schallemissionsanalyse ist es nicht möglich, Spanndrahtbrüche zu finden, die vor dem Beginn der Überwachung entstanden sind. Das Dokument richtet sich an Baulastträger, Anbieter und Betreiber von Monitoringsystemen auf Basis der Schallemissionsanalyse sowie Ingenieurbüros, welche die Ergebnisse der Überwachung bewerten und Maßnahmen daraus ableiten. Es gibt Hinweise zur Planung, Ausschreibung, Installation und zum Betrieb von Monitoringsystemen zur Detektion von Spanndrahtbrüchen mit Schallemission sowie zur Überprüfung der Funktion installierter Systeme. Zur Funktionskontrolle werden Signale mit der Referenzquelle am Bauwerk ausgelöst. Diese Signale sind zu detektieren, innerhalb der vorgegebenen Genauigkeit zu lokalisieren und die vorgegebene Alarmkette muss angestoßen werden. KW - Schallemission KW - Brücke KW - Spannbeton KW - Spannstahlbruch PY - 2024 SN - 978-3-947971-34-3 VL - Richtlinie SE 05 SP - 1 EP - 33 PB - Deutsche Gesellschaft für Zerstörungsfreie Prüfung (DGZfP) CY - Berlin ET - Ausgabe Mai 2024 AN - OPUS4-60679 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kremberg, Jan A1 - Häßler, Dustin A1 - Stelzner, Ludwig A1 - Hothan, Sascha T1 - Brandversuche an mechanisch belasteten Carbonzuggliedern T1 - Fire testing of loaded carbon tension members N2 - Die Anwendung von Zuggliedern aus Carbon ist durch die außergewöhnlich gute Ermüdungs- sowie hohe Zugfestigkeit des Werkstoffs motiviert. Ferner ergibt sich gegenüber Stahl eine deutliche Reduzierung des Querschnitts. Perspektivisch sollen damit u. a. Stahlzugglieder im Netzwerkbogenbrückenbau ersetzt werden. Das Tragverhalten von Carbonzuggliedern im Brandfall ist jedoch bislang unbekannt. Daher wurden mittels Bauteilbrandversuchen die Versagensmechanismen untersucht sowie anhand gewonnener Versuchsdaten eine exemplarische Einschätzung zur Gleichwertigkeit gegenüber konventionellen Stahlzuggliedern vorgenommen. Der Beitrag beschreibt realmaßstäbliche Brandversuche an mechanisch belasteten Carbonzuggliedern, die im Rahmen des Verbundforschungsvorhabens NeZuCa durchgeführt wurden. Das Versuchsprogramm umfasste vier Carbonzugglieder mit kreisrunden Querschnitten in zwei verschiedenen Durchmessern, 36 mm und 51 mm. In Ermangelung eines präskriptiven Brandszenarios für den im Projekt vorgesehenen Anwendungsfall und aus Gründen der Vergleichbarkeit erfolgte die Brandbeanspruchung nach Einheitstemperaturzeitkurve (ETK). Neben den Längsverformungen der Zugglieder wurden auch die Bauteil und Brandraumtemperaturen aufgezeichnet. KW - Netzwerkbogenbrücke KW - Carbonzugglied KW - Feuerwiderstand KW - Brandversuche PY - 2023 DO - https://doi.org/10.1002/stab.202200081 SN - 1437-1049 SN - 0038-9145 VL - 92 IS - 7 SP - 427 EP - 436 PB - Ernst & Sohn CY - Berlin AN - OPUS4-57926 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Andrés Arcones, Daniel T1 - Evaluation of Model Bias Identification Approaches Based on Bayesian Inference and Applications to Digital Twins N2 - In recent years, the use of simulation-based digital twins for monitoring and assessment of complex mechanical systems has greatly expanded. Their potential to increase the information obtained from limited data makes them an invaluable tool for a broad range of real-world applications. Nonetheless, there usually exists a discrepancy between the predicted response and the measurements of the system once built. One of the main contributors to this difference in addition to miscalibrated model parameters is the model error. Quantifying this socalled model bias (as well as proper values for the model parameters) is critical for the reliable performance of digital twins. Model bias identification is ultimately an inverse problem where information from measurements is used to update the original model. Bayesian formulations can tackle this task. Including the model bias as a parameter to be inferred enables the use of a Bayesian framework to obtain a probability distribution that represents the uncertainty between the measurements and the model. Simultaneously, this procedure can be combined with a classic parameter updating scheme to account for the trainable parameters in the original model. This study evaluates the effectiveness of different model bias identification approaches based on Bayesian inference methods. This includes more classical approaches such as direct parameter estimation using MCMC in a Bayesian setup, as well as more recent proposals such as stat- FEM or orthogonal Gaussian Processes. Their potential use in digital twins, generalization capabilities, and computational cost is extensively analyzed. T2 - 5th ECCOMAS Thematic Conference on Uncertainty Quantificationin Computational Sciences and Engineering CY - Athens, Greece DA - 12.06.2023 KW - Digital Twin KW - Simulation Models KW - Uncertainty Quantification KW - Model Bias PY - 2023 UR - https://2023.uncecomp.org/ AN - OPUS4-58226 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Jafari, Abbas A1 - Vlachas, K. A1 - Chatzi, E. A1 - Unger, Jörg F. T1 - A Bayesian framework for constitutive model identification via use of full field measurements, with application to heterogeneous materials N2 - In this paper, we present a Bayesian framework for the identification of the parameters of nonlinear constitutive material laws using full-field displacement measurements. The concept of force-based Finite Element Model Updating (FEMU-F) is employed, which relies on the availability of measurable quantities such as displacements and external forces. The proposed approach particularly unfolds the advantage of FEMU-F, as opposed to the conventional FEMU, by directly incorporating information from full-field measured displacements into the model. This feature is well-suited for heterogeneous materials with softening, where the localization zone depends on the random microstructure. Besides, to account for uncertainties in the measured displacements, we treat displacements as additional unknown variables to be identified, alongside the constitutive parameters. A variational Bayesian scheme is then employed to identify these unknowns via approximate posteriors under the assumption of multivariate normal distributions. An optimization problem is then formulated and solved iteratively, aiming to minimize the discrepancy between true and approximate posteriors. The benefit of the proposed approach lies in the stochastic nature of the formulation, which allows to tackle uncertainties related to model parameters and measurement noise. We verify the efficacy of our proposed framework on two simulated examples using gradient damage model with a path-dependent nonlinear constitutive law. Based on a nonlocal equivalent strain norm, this constitutive model can simulate a localized damage zone representing softening and cracking. The first example illustrates an application of the FEMU-F approach to cracked structures including sensitivity studies related to measurement noise and parameters of the prior distributions. In this example, the variational Bayesian solver demonstrates a sizable advantage in terms of computational efficiency compared to a traditional least-square optimizer. The second example demonstrates a sub-domain analysis to tackle challenges associated with limited domain knowledge such as uncertain boundary conditions. KW - Constitutive model identification KW - Full-field measurements KW - Variational Bayes KW - Force-based finite element model updating KW - FEMU-F PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-615476 DO - https://doi.org/10.1016/j.cma.2024.117489 SN - 1879-2138 VL - 433 IS - Part A SP - 1 EP - 32 PB - Elsevier B.V. AN - OPUS4-61547 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Fürst, Richard A1 - Häßler, Dustin A1 - Stelzner, Ludwig A1 - Hothan, Sascha T1 - Development of an in situ test method to assess the fire resistance of steel members with applied intumes-cent coating N2 - Intumescent coatings are commonly used in civil engineering to improve the fire resistance of steel constructions. Exposed to fire, the intumescent coating reacts and forms a thermal protective char around the steel member. Thus, the heating of the steel is delayed, and a higher fire resistance can be achieved. Generally, the scope of application and the durability of intumescent coatings are described in national approvals or European Technical Assessment (ETA) documents. Due to environmental conditions, intumescent coatings are subjected to ageing effects, which can reduce their durability and thermal protection performance. Available in situ methods to investigate the performance of applied intumescent coatings, such as visual inspection, flame exposure testing, adhesive tensile tests or chemical analysis, are not fully conclusive. Therefore, in the civil engineering practice, there is an increasing demand to verify the fire resistance of existing steel structures with applied intumescent coatings necessary in several cases, e.g., the working life is exceeded, the visual appearance of the intumescent coating changed or the information about the applied product is missing. The research presented in the paper shows the progress of the ongoing research project "INSIST" at BAM [1], where a new in situ method is being developed to assess the actual fire resistance of existing steel structures with applied intumescent coating. The investigation is based on a development of the in situ test procedure and a mobile prototype furnace. T2 - 10th Symposium Structural Fire Engineering CY - Braunschweig, Germany DA - 24.09.2024 KW - In situ KW - Intumescent coating KW - Steel structures KW - Test procedure PY - 2024 SP - 1 EP - 15 AN - OPUS4-61275 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Thibaux, Philippe A1 - Thiele, Marc A1 - Van Wittenberghe, Jeroen A1 - Baeßler, Matthias T1 - Comparison of resonance and hydraulic testing on large scale fatigue tests of welded tubular joints for offshore wind turbine foundations N2 - Jackets structures as foundations for offshore wind energy converters are efficient solutions. But these structures require the welding of a large number of joints. The design of the Jacket structures is typically driven by fatigue. Therefore, consequently the fatigue strength of the joints is a primary parameter for an optimized design. The present paper investigates if tubular joints produced by manual welding using the current techniques have an improved performance compared to the relevant standards that are applied for the design of the foundations. To investigate this, 4 full-scale tests in geometry representative of a structure were performed, 2 using a resonance method and 2 using a three-point bending method with hydraulic actuators. The results are similar, with cracks initiated early and extending extensively before failure. The results are very close to the current T-curve from DNV RP-C203 applied for tubular joints. KW - Fatigue KW - Tubular joints KW - Resonance testing KW - Steel welds PY - 2025 DO - https://doi.org/10.1016/j.ijfatigue.2024.108797 SN - 0142-1123 VL - 193 SP - 1 EP - 16 PB - Elsevier Ltd. AN - OPUS4-62373 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Recknagel, Christoph T1 - Fugenfüllungen - Anforderungen, Eigenschaften, Prüfungen, Dauerhaftigkeit N2 - Fugenfüllungen im kommunalen Stadtstrassenbau unterliegen besonderen mechanischen Beanspruchungen. Hier kommt es bereits bei der Planung darauf an, Fugenausführungen und insbesondere Fugenfüllstoffe bewusst nach ingenieurtechnischen Gesichtspunkten auszuwählen. Dazu ist das ingenieurtechnische Verständnis der relevanten Fugenfüllstoffe - Funktionsweise, Leistungskriterien, Prüfungen, Dauerhaftigkeit - von entscheidender Bedeutung. Der Vortrag erläutert nicht nur die maßgebenden Fugenfüllstoffe unter den vorgenannten Schwerpunkten, sondern stellt auch das Verständnis zu den Rahmenbedingungen, Grundlagen und Wirkmechanismen des entsprechenden technischen Regelwerkes her. Neueste Entwicklungen werden den Praxisvertretern näher gebracht und erläutert. Die Zusammenhänge und Strategien zur Weiterentwicklung der „Betonstrasse der Zukunft“ werden diskutiert und dargestellt. T2 - Qualitätsgemeinschaft Städtischer Strassenbau (QGS) - Weiterbildung für technisches Führungspersonal CY - Berlin, Germany DA - 14.06.2022 KW - Kommunale Infrastruktur KW - Betonfahrbahndecken KW - Qualitätssicherung KW - Verfügbarkeit PY - 2022 AN - OPUS4-55070 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ratkovac, Mirjana T1 - Perspectives on Wind and Wave Load Reconstruction from SHM Data for Offshore Wind Turbines N2 - As many wind turbines approach the end of their design lifetime, from a technical point of view, comprehensive fatigue analysis of all critical parts is necessary to decide what comes after – continued operation, repowering, or decommissioning. Typically, it is a two-stage evaluation process consisting of a physical inspection of the structure and an analytical part to compare the design and actually experienced loading conditions. Structural health monitoring helps to reduce the uncertainties in the estimations by providing insight into deviations between the designed and the built structure. Furthermore, it allows the evaluation of the consumed fatigue lifetime by analyzing the strain measurements that mirror the actual structural response to experienced environmental and operational conditions. However, the measurement values are limited to a sparse number of instrumented spots on the structure, and further extrapolation to the non-instrumented (critical) sections is required to perform a complete fatigue assessment. One known approach is the external force reconstruction, which has only scarcely been considered for application in offshore wind turbines. In order to extend the previously developed thrust force reconstruction framework, this work discusses the possibilities and challenges of wind and wave loading reconstruction in offshore wind turbine support structures. T2 - 4th International Conference on Health Monitoring of Civil & Maritime Structures (HeaMES 2023) CY - Online meeting DA - 12.06.2023 KW - Wind turbines KW - Force reconstruction KW - Structural Health Monitoring PY - 2023 AN - OPUS4-57687 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schepers, Winfried A1 - Brinkgreve, Ronald B. J. A1 - Holtzendorff, Kira A1 - Wegener, Dirk A1 - Appel, Silke A1 - Efthymiou, Georgia A1 - Krajewski, Wolfgang A1 - Machaček, Jan A1 - Meier, Thomas A1 - Nseir, Bashar A1 - Rangelow, Peter A1 - Schmitt, Jürgen A1 - Staubach, Patrick A1 - Vrettos, Christos T1 - Numerische Ermittlung von Baugrundschwingungen bei dynamisch belasteten Fundamenten: Empfehlungen zur Modellierung T1 - Numerical analysis of soil vibrations due to vibrating foundations: Guidance for model design N2 - AbstractIn der Praxis tätige geotechnisch Planende kommen in zunehmendem Maße mit dynamischen Fragestellungen in Berührung. Hersteller von geotechnischer Berechnungssoftware haben entsprechend ihre ursprünglich für statische Aufgabenstellungen konzipierten Produkte um die Möglichkeit zur Lösung von Wellenausbreitungsproblemen im Baugrund erweitert. Den Anwendern fehlt aber häufig die notwendige Erfahrung zur Durchführung dieser Art von numerischen Berechnungen. Die Arbeitskreise 1.4 „Baugrunddynamik“ und 1.6 „Numerik in der Geotechnik“ der Deutschen Gesellschaft für Geotechnik (DGGT) haben diese Entwicklung aufgegriffen und einen gemeinsamen Unterarbeitskreis „Numerik in der Baugrunddynamik“ gegründet. Der vorliegende Beitrag stellt die aktuellen Ergebnisse der Arbeit des Unterarbeitskreises vor und fasst die gewonnenen Erkenntnisse in Form von Empfehlungen zusammen. N2 - Geotechnical engineers are increasingly concerned with wave propagation problems. Manufacturers of geotechnical analysis software added features for soil dynamic analyses to their products initially devised for static geotechnical analyses. Though, users often lack the experience for conducting such advanced numerical analyses. Working groups 1.4 "Soil dynamics" and 1.6 "Numerical analyses in geotechnical engineering" of DGGT German Society for Geotechnical Engineering established a joint subgroup "Numerical analyses in soil dynamics" to address this shortcoming. The present paper presents the work of the subgroup so far and provides some guidance on conducting numerical analyses in soil dynamics. KW - Wellenausbreitung KW - Numerische Methoden KW - Empfehlungen KW - Modellgröße KW - Zeitschrittweite PY - 2024 DO - https://doi.org/10.1002/gete.202400016 SN - 0172-6145 VL - 47 IS - 4 SP - 254 EP - 268 PB - Ernst CY - Berlin AN - OPUS4-62078 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schneider, Ronald A1 - Simon, Patrick A1 - Herrmann, Ralf A1 - Hille, Falk A1 - Baeßler, Matthias T1 - Bestandteile Digitaler Zwillinge im Erhaltungsmanagement von Verkehrsbrücken T1 - Components of digital twins in the operation and maintenance management of traffic bridges N2 - Digitale Zwillinge werden zukünftig ein integraler Bestandteil des Erhaltungsmanagements von Verkehrsbrücken sein. In diesem Beitrag wird argumentiert, dass sie nicht nur als digitale Abbilder physikalischer Bauwerke verstanden werden sollten, sondern als eine umfassende digitale Methode, die durch die Integration von Datenerfassung, Erhaltungsmaßnahmen, Datenmanagement, Bauwerksbewertung und Entscheidungsunterstützung die Bauwerksüberwachung und ‐erhaltung verbessert. In diesem Zusammenhang wird betont, dass der Übergang von der reaktiven zur prädiktiven Erhaltung durch den Einsatz von Digitalen Zwillingen nur dann realisierbar ist, wenn neben den erforderlichen diagnostischen und prognostischen Zustandsanalysen auch Methoden zur Optimierung von Entscheidungen über Datenerfassung und Erhaltungsmaßnahmen implementiert werden. Zur Veranschaulichung der Diskussion werden in diesem Beitrag exemplarisch zwei Bestandteile eines Digitalen Zwillings für das Erhaltungsmanagement von Verkehrsbrücken am Beispiel einer Eisenbahnbrücke demonstriert. Dabei wird zum einen gezeigt, wie Monitoringdaten mittels eines Datenmanagementsystems strukturiert verwaltet und für angeknüpfte Analysen bereitgestellt werden. Zum anderen erfolgt im Rahmen einer bauwerksspezifischen Einwirkungsermittlung eine Zugidentifikation anhand von gemessenen Schwellenschwingungen. N2 - Digital twins will become an integral part of the operation and maintenance management of traffic bridges in the future. This paper argues that they should not only be understood as digital representations of physical structures but as a digital methodology that enhances the operation and maintenance of bridges through the integration of data collection, maintenance actions, data management, structural assessment, and decision support. In this context, it is emphasized that the transition from reactive to predictive maintenance using digital twins can only be achieved if, in addition to the necessary diagnostic and prognostic condition analyses, methods for optimizing decisions on data collection and maintenance actions are also implemented. To illustrate this discussion, two key components of a digital twin for the operation and maintenance management of traffic bridges are demonstrated using a railway bridge as an example. First, it is shown how monitoring data can be systematically managed and made available for subsequent analyses through a data management system. Second, train identification based on measured sleeper vibrations is conducted as part of an object-specific load assessment. KW - Digitale Zwillinge KW - Erhaltung KW - Inspektion KW - Monitoring KW - Brücken PY - 2025 DO - https://doi.org/10.1002/bate.202400101 SN - 1437-0999 SP - 1 EP - 11 PB - Ernst & Sohn CY - Berlin AN - OPUS4-62837 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Simon, Patrick A1 - Helmrich, M. A1 - Herrmann, Ralf A1 - Schneider, Ronald A1 - Baeßler, Matthias A1 - Lorelli, S. A1 - Morgenthal, G. T1 - Maintalbrücke Gemünden: Bauwerksmonitoring und -identifikation aus einem Guss T1 - Maintalbrücke Gemünden – Integrated structural health monitoring and UAS diagnostics N2 - Die Infrastruktursysteme der Industriestaaten erfordern heute und in Zukunft ein effizientes Management bei alternder Bausubstanz, steigenden Lasten und gleichbleibend hohem Sicherheitsniveau. Digitale Technologien bieten ein großes Potenzial zur Bewältigung der aktuellen und künftigen Herausforderungen im Infrastrukturmanagement. Im BMBF-geförderten Projekt Bewertung alternder Infrastrukturbauwerke mit digitalen Technologien (AISTEC) wird untersucht, wie unterschiedliche Technologien und deren Verknüpfung gewinnbringend eingesetzt werden können. Am Beispiel der Maintalbrücke Gemünden werden ein sensorbasiertes Bauwerksmonitoring, bildbasierte Inspektion mit durch Kameras ausgestatteten Drohnen (UAS) und die Verknüpfung digitaler Bauwerksmodelle umgesetzt. Die aufgenommenen Bilder dienen u. a. als Grundlage für spätere visuelle Anomaliedetektionen und eine 3D-Rekonstruktion, welche wiederum für die Kalibrierung und Aktualisierung digitaler Tragwerksmodelle genutzt werden. Kontinuierlich erfasste Sensordaten werden ebenfalls zur Kalibrierung und Aktualisierung der Tragwerksmodelle herangezogen. Diese Modelle werden als Grundlage für Anomaliedetektionen und perspektivisch zur Umsetzung von Konzepten der prädiktiven Instandhaltung verwendet. Belastungsfahrten und historische Daten dienen in diesem Beitrag der Validierung von kalibrierten Tragwerksmodellen. N2 - Infrastructure systems of industrialised countries today and in the future require efficient management with an ageing stock, increasing loads while simultaneously maintaining a high level of safety. Digital technologies offer great potential for the current and future challenges in infrastructure management. The BMBF-funded project AISTEC is investigating how the individual technologies and their interconnection can be used beneficially. With the Maintalbrücke in Gemünden as an exemplary application, sensor-based structural monitoring, image-based inspection using unmanned aircraft systems (UAS) equipped with cameras and the integration of digital structural models are being implemented. The recorded images serve, among others, as basis for subsequent anomaly detection and a 3D reconstruction, which in turn are used for updating digital structural models. Continuously recorded sensor data is used to update the parameters of the structural models, which in turn provide the basis for predictive maintenance. Load tests are used to validate the models. KW - Bauwerksüberwachung KW - Strukturmonitoring KW - Structural Health Monitoring KW - Modell-Update KW - UAS KW - Belastungstest KW - Structural system identification KW - Structural health monitoring KW - Model update KW - UAS KW - Load tests PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-554924 DO - https://doi.org/10.1002/bate.202100102 SN - 0932-8351 VL - 99 IS - 3 SP - 163 EP - 172 PB - Ernst & Sohn CY - Berlin AN - OPUS4-55492 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schneider, Ronald A1 - Simon, Patrick A1 - Hille, Falk A1 - Herrmann, Ralf A1 - Baeßler, Matthias T1 - Vibration-based system identification of a large steel box girder bridge N2 - The Bundesanstalt für Materialforschung und -prüfung (BAM) collaborates with TNO to develop a software framework for automated calibration of structural models based on monitoring data. The ultimate goal is to include such models in the asset management process of engineering structures. As a basis for developing the framework, a multi-span road bridge consisting of ten simply supported steel box girders was selected as a test case. Our group measured output-only vibration data from one box girder under ambient conditions. From the data, we determined eigenfrequencies and mode shapes. In parallel, we developed a preliminary structural model of the box girder for the purpose of predicting its modal properties. In this contribution, we provide an overview of the measurement campaign, the operational modal analysis, the structural modeling and qualitatively compare the identified with the predicted modes. As an outlook, we discuss the further steps in the calibration process and future applications of the calibrated model. T2 - XII International Conference on Structural Dynamics (EURODYN 2023) CY - Delft, The Netherlands DA - 02.07.2023 KW - Verkehrsinfrastukturen KW - SHM KW - Model updating KW - System identification KW - Operational modal analysis PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-605041 DO - https://doi.org/10.1088/1742-6596/2647/18/182039 SN - 1742-6596 VL - 2647 IS - 18 SP - 1 EP - 9 PB - IOP Publishing CY - Bristol AN - OPUS4-60504 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Thiele, Marc A1 - Makris, Ralf T1 - Specification for high-speed tensile tests on reinforcement bar coupler systems N2 - This document presents the specification for the execution and evaluation of high-speed tensile tests on reinforcement bar coupler systems. This specification was developed at BAM - Bundesanstalt für Materialforschung und -prüfung (Federal Institute for Materials Research and Testing, Germany) - following test principles from related international standards. The present document represents the latest status of the test specification. It is noted that until 2010 the test procedure was characterised on a test velocity based on L0. In an improved test conception and after intensive investigations in cooperation with industry partners, this procedure has been updated to consider instead a test velocity based on Lr, since this warrants more comparable and meaningful results. KW - Test specification KW - Coupler systems KW - High-speed KW - Tensile test KW - Reinforcement PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-525075 DO - https://doi.org/10.26272/opus4-52507 SP - 1 EP - 29 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin ET - V01 AN - OPUS4-52507 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hüsken, Götz A1 - Shamsuddoha, Md A1 - Thiele, Marc A1 - Baeßler, Matthias A1 - Kühne, Hans-Carsten T1 - Comparison of cracks formed in scaled grouted connection of offshore energy structures under static and cyclic loads N2 - Global energy consumption will increase in the future necessitating both fossil fuels and renewable energy choices - especially wind energy. Such high energy demand requires installation of offshore energy structures, rigs, platforms and towers, which are susceptible to adverse environmental conditions along with maintenances. Due to their large size and remote locations, cylindrical grouted joints are often adopted between substructure and foundation in these offshore platforms and wind structures such as monopiles. However, these connections are composite structures with exterior sleeve, interior pile and infill mortar. Degradation and settlements were reported inside similar connections, which were installed in last three decades. Besides, grouting in the offshore sites were proven difficult to obtain ideal load bearing capacity. In-situ loading conditions were also found to be affecting the failure mechanism inside such connections. This study aims at characterizing the nature of cracks generated in these grouted connections under both static and cyclic loading. Scaled grouted joints were manufactured using a novel reusable mold, and connections were loaded to failure to visualize the main failure patterns. An assessment between failure under these two types of load is drawn along with comparison to previously available literature. T2 - 5th International Conference on Smart Monitoring, Assessment and Rehabilitation of Civil Structures CY - Potsdam, Germany DA - 27.08.2019 KW - Grouted connection KW - Crack formation KW - Crack pattern KW - Static load KW - Cyclic load PY - 2019 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-487961 SP - Th.2.A.1-1 EP - Th.2.A.1-9 AN - OPUS4-48796 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Fiedler, Georg A1 - Hering, Marcus A1 - Schubert, T. A1 - Bracklow, F. A1 - Nerger, Deborah A1 - Hille, Falk A1 - Beckmann, B. ED - Wuttke, F. ED - Aji, H. ED - Özarmut, A. T1 - Schädigung von Stahlbetonplatten infolge eines harten Anpralls - Vergleich von halb-empirischen Methoden und experimentellen Ergebnissen N2 - Schutzbauwerke von systemkritischen Infrastruktureinrichtungen wie Betonwände und Betonbarrieren müssen Anprallereignissen oder schweren Unfällen in einem vertretbaren Maße widerstehen können. Anprallereignisse können verschiedenster Natur sein. Hierzu zählen Steinschlag, Fahrzeug- oder Flugzeuganprall oder auch Geschosseinschlag. Geschosseinschläge bzw. Bei den Anprall- oder Impaktereignissen wird zwischen hartem und weichem Anprall unterschieden, bei hartem Anprall verformt sich der Anprallkörper nicht oder nur geringfügig, bei weichem Anprall stark. In diesem Artikel werden Forschungsergebnisse zum harten Anprall auf bewehrte Stahlbetonplatten vorgestellt, welche über die letzten Jahre im Rahmen eines Kooperationsprojekts zwischen dem Institut für Massivbau (IMB) der Technischen Universität Dresden (TUD) und der Bundesanstalt für Materialforschung und -prüfung (BAM) durchgeführt wurden. Auf dem Gelände des Otto-Mohr-Labors (OML) der TUD steht hierfür ein speziell konzipierter Fallturm zur Verfügung. Der Aufbau im Fallturm lässt aktuell druckluftbeschleunigte Impaktversuche mit mittleren Anprallgeschwindigkeiten zu. Die durch Anprall geschädigten Stahlbetonplatten wurden anschließend bei der BAM mit Strahlung tomographisch untersucht. Diese Untersuchungen ermöglichen einen Blick auf die Schädigung und Rissstruktur im Inneren der Stahlbetonplatten. Ein Schwerpunkt der durchgeführten Untersuchung ist der Vergleich von Testergebnissen mit den häufig angewendeten halbempirischen Berechnungsmethoden zu den erforderlichen Wandstärken und den sich daraus ergebenden zulässigen Anprallgeschwindigkeiten. Bei diesem Vorgehen wird auch die mit analytischen Methoden abschätzbare Durchdringungsgeschwindigkeit bzw. Austrittgeschwindigkeit eines Projektils ermittelt und mit den realen Testergebnissen verglichen. Außerdem wird der Einfluss von sowohl externen als auch internen Strukturparametern auf Risse betrachtet und ein Fazit abgeleitet. Weiterhin werden laufende und zukünftige wissenschaftliche Untersuchungen zum Anprall auf Betonstrukturen am IMB und der BAM genannt. T2 - 18. D-A-CH-Tagung CY - Kiel, Germany DA - 13.09.2023 KW - Impakt KW - Harter Anprall an Stahlbetonstrukturen KW - Fallturm PY - 2023 SN - 978-3-930108-15-1 SP - 471 EP - 479 PB - Deutsche Gesellschaft für Erdbebeningenieurwesen und Baudynamik (DGEB) e.V. AN - OPUS4-58341 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Thiele, Marc T1 - Detection and monitoring of the fatigue crack growth on welds – Application-oriented use of NDT methods N2 - Early detection of fatigue cracks and accurate measurements of the crack growth play an important role in the maintenance and repair strategies of steel structures exposed to cyclic loads during their service life. Observation of welded connections is especially of high relevance due to their higher susceptibility to fatigue damage. The aim of this contribution was to monitor fatigue crack growth in thick welded specimens during fatigue tests as holistically as possible, by implementing multiple NDT methods simultaneously in order to record the crack initiation and propagation until the final fracture. In addition to well-known methods such as strain gauges, thermography, and ultrasound, the crack luminescence method developed at the Bundesanstalt für Materialforschung und -prüfung (BAM), which makes cracks on the surface particularly visible, was also used. For data acquisition, a first data fusion concept was developed and applied in order to synchronize the data of the different methods and to evaluate them to a large extent automatically. The resulting database can ultimately also be used to access, view, and analyze the experimental data for various NDT methods. During the conducted fatigue tests, the simultaneous measurements of the same cracking process enabled a comprehensive comparison of the methods, highlighting their individual strengths and limitations. More importantly, they showed how a synergetic combination of different NDT methods can be beneficial for implementation in large-scale fatigue testing but also in monitoring and inspection programs of in-service structures - such as the support structures of offshore wind turbines. T2 - Fatigue Design 2023 CY - Senlis, France DA - 29.11.2023 KW - Crack growth KW - Fatigue KW - NDT KW - Welded PY - 2023 AN - OPUS4-62374 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schneider, Ronald T1 - Digitaler Zwilling im Erhaltungsmanagement von Straßenbrücken N2 - Digitale Zwillinge werden zukünftig ein integraler Bestandteil des Erhaltungsmanagements von Straßenbrücken sein. In diesem Beitrag wird argumentiert, dass sie nicht nur als digitale Abbilder physikalischer Bauwerke verstanden werden sollten, sondern als eine umfassende digitale Methode, die durch die Integration von Datenerfassung, Erhaltungsmaßnahmen, Datenmanagement, Bauwerksbewertung und Entscheidungsunterstützung die Bauwerksüberwachung und -erhaltung verbessert. In diesem Zusammenhang wird betont, dass der Übergang von der reaktiven zur prädiktiven Erhaltung durch den Einsatz von Digitalen Zwillingen nur dann realisierbar ist, wenn neben den erforderlichen diagnostischen und prognostischen Zustandsanalysen auch Methoden zur Optimierung von Entscheidungen über Datenerfassung und Erhaltungsmaßnahmen implementiert werden. Zur Veranschaulichung der Diskussion werden in diesem Beitrag exemplarisch zwei Bestandteile eines Digitalen Zwillings für das Erhaltungsmanagement von Verkehrsbrücken am Beispiel einer Eisenbahnbrücke demonstriert. Dabei wird zum einen gezeigt, wie Monitoringdaten mittels eines Datenmanagementsystems strukturiert verwaltet und für angeknüpfte Analysen bereitgestellt werden. Zum anderen erfolgt im Rahmen einer bauwerksspezifischen Einwirkungsermittlung eine Zugidentifikation anhand von gemessenen Schwellenschwingungen T2 - Workshop „Digitaler Zwilling im Lebenszyklusmanagement" der AG BIM in der Bauwerkserhaltung des Koordinierungsausschusses Erhaltung (KoA-Erhaltung) der B/L-DB Konstruktiver Ingenieurbau CY - Potsdam, Germany DA - 09.04.2025 KW - Digitale Zwillinge KW - Erhaltung KW - Inspektion KW - Monitoring KW - Brücken PY - 2025 AN - OPUS4-62951 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kowitz, Astrid A1 - Wu, Cheng-Chieh A1 - Helmerich, Rosemarie A1 - Hille, Falk A1 - Kadoke, Daniel A1 - Gründer, Klaus-Peter A1 - Hauser, S. A1 - Schwarzinger, H. ED - Bland, S. T1 - Impact on a micro-reinforced UHPC: Experimental studies versus numerical modeling N2 - Within the presented research project, experimental and numerical investigations were performed to develop a thin-shelled, modular, mobile element system made of a micro-reinforced ultra-high-performance ductile concrete (DUCON®). Material parameters were experimentally determined to adapt the material model within the numerical analysis applying the Drucker-Prager relationship. Afterwards, for validation of the numerical models, quasi-static and high-velocity impact tests were performed on plate-like structures. Finally, a suitable geometry of transportable barrier elements will be designed, which provides a maximum of resistance against impact by a minimum of weight and a maximum of mobility. KW - UHPC KW - Impact KW - DUCON® KW - Quasi-static and dynamic tests KW - Micro-reinforcement KW - Ductility KW - Mobile elements KW - Numerical modeling KW - Stereo photogrammetry KW - Compressive strength KW - E-modulus PY - 2019 UR - https://www.sciencedirect.com/science/article/pii/S2214785319305115?dgcid=author DO - https://doi.org/10.1016/j.matpr.2019.03.152 SN - 2214-7853 VL - 12 IS - 2 SP - 474 EP - 483 PB - Elsevier Ltd CY - Amsterdam AN - OPUS4-48181 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Stelzner, Ludwig T1 - Zum Feuerwiderstand vorgespannter Carbonbetondecken N2 - Der Einsatz von hoch zugbeanspruchbarem und korrosionsbeständigem Carbongelege anstelle herkömmlichen Spannstahls ermöglicht es Beton vorzuspannen und gleichzeitig die Betondeckung auf ein für den Verbund nötiges Minimum zu reduzieren. Der Wechsel von massiven zu filigranen Bauteilen führt in der Regel aufgrund der geringeren thermischen Masse zu einer Abnahme des Feuerwiderstandes. Der Beitrag stellt Versuchsergebnisse zum Abplatz- und Hochtemperaturverhalten von Carbonbeton vor, die im Rahmen des Verbundvorhabens „Vorgespannte Carbonbetondecken mit reduzierten Querschnitten“ (CaPreFloor) erzielt wurden. Für die Untersuchung der Tragfähigkeit bei hohen Temperaturen wurden 4-Punktbiegeversuche mit instationärer Temperaturbeanspruchung an vorgespannten Carbonbetonplatten bei Variation des Carbongeleges und des Vorspanngrades durchgeführt. Ferner erfolgte die Analyse der Abplatzneigung an bewehrten und unbewehrten Bauteilen mittels Brandversuchen unter Einheits-Temperaturzeitkurve. T2 - Carbonbetontage 2024 CY - Dresden, Germany DA - 24.09.2024 KW - Carbonbeton KW - Feuerwiderstand KW - Abplatzverhalten PY - 2024 AN - OPUS4-62429 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kruschwitz, Sabine T1 - Non-destructive testing application examples using the NMR core-analyzing tomograph N2 - Nuclear magnetic resonance (NMR) with focus on 1H protons is increasingly applied for non-destructive testing applications. Besides mobile NMR, laboratory devices such as the NMR core-analyzing tomograph are used. As their magnetic field is more homogeneous, they enable measurements with higher signal-to-noise ratios (SNR), but with limited sample sizes. The tomograph presented here (8.9 MHz) was constructed for a maximum sample diameter of 70 mm and length of up to 1 m. The resolution, the echo time (min. 50 µs), the SNR and the measurement type can be adjusted by means of exchangable coils. The tomograph enables measurements along the complete sensitive length, slice-selective and even 2- or 3-dimensional measurements. A movable sample lifting system thereby allows a precise positioning of the sample. T2 - Magnetic Resonance in Porous Medie (MRPM) 2022 CY - Online meeting DA - 21.08.2022 KW - Spalling KW - Nuclear magnetic resonance KW - Tomography KW - Moisture transport KW - Frost salt attach PY - 2022 AN - OPUS4-55828 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Erning, Johann Wilhelm T1 - Crevice corrosion of 304 stainless steel under the influence of chlorine and chloride N2 - Der Einfluss von elektrolytisch erzeugten Desinfektionsmitteln auf die Spaltkorrosion des nichtrostenden Stahls 1.4301 wird dargestellt. Der Einfluss der Chlor- und Chloridkonzentration wird ermittelt N2 - The influence of electrolytically produced disinfectants on crevice corrosion of 304 stainless steel is shown. The influence of chlorine and chloride concentrations is determined. T2 - Kormat 2020 CY - Online meeting DA - 26.11.2020 KW - Crevice corrosion KW - Werkstoffe KW - Stainless steel KW - Disinfection PY - 2020 AN - OPUS4-51698 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - von Werder, Julia T1 - Funktionalisierung von Fasern für zementgebundene Materialien - ausgewählte Prüfmethoden N2 - Die geringe Zugfestigkeit von zementgebundenen Materialien kann durch die Zugabe von Fasern maßgeblich verbessert werden. Ziel eines gemeinsamen Verbundprojekts mit einem Industriepartner war die Erhöhung der Leistungsfähigkeit von kurzen Polymer- und Carbonfasern durch eine Verbesserung des Verbundes zwischen Faseroberfläche und Zementsteinmatrix. Von der IONYS AG wurde dazu eine spezielle Funktionalisierung entwickelt, die über eine Hydrophilisierung der Faseroberfläche eine chemische Anbindung an die Zementsteinmatrix gewährleistet. Aufgabe der BAM war es, die Effizienz der neuen Beschichtung bezüglich der Erhöhung der Nachrissbiegezugfestigkeit und der Reduzierung der Schwindrissbildung während der Erhärtungsphase zu quantifizieren. Die Ergebnisse zeigen, dass die Funktionalisierung die Neigung zur Schwindrissbildung für die Carbonfasern und in noch stärkerem Maße für die Polymerfasern reduziert. Eine Erhöhung der Nachrissbiegezugfestigkeit konnte dagegen nur für die deutlich steiferen Carbonfasern nachgewiesen werden. T2 - 10. Kolloquium Industrieböden CY - Esslingen, Germany DA - 03.03.2020 KW - Fibres KW - Cementitious materials KW - Shrinkage KW - Strain hardening PY - 2020 AN - OPUS4-51914 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kotula, Stefan T1 - Messsystemanalyse („Ringversuch“) zu WIPANO-Vorhaben „GELELEK“ – Zusammenfassung der Ergebnisse N2 - Im Rahmen des WIPANO-Vorhabens „GELELEK“ wurde ein Ringversuch durchgeführt, bei dem ca. 20 Teilnehmer aus Wirtschaft und Forschung teilnahmen. Dabei wurde eine neuartige elektrochemische Messung von Zinkoberflächen durchgeführt, welche an der BAM entwickelt und für industrielle Anwendung optimiert wurde. Dabei diente ein an der BAM geschriebener Normvorschlag als Anleitung. In dem Vortrag werden die Ergebnisse und Auswertungen der Messdaten vorgestellt. T2 - Sitzung der Ad hoc Gruppe "GELELEK" im DIN-Normenausschuss Materialprüfung (NMP) CY - Online Meeting DA - 07.09.2021 KW - Deckschichtbildung KW - Gelartige Elektrolyte KW - Korrosionsuntersuchungen KW - Ringversuch KW - Normung KW - Zink PY - 2021 AN - OPUS4-53280 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Babutzka, Martin T1 - Vorstellung des WIPANOVerbundforschungsvorhabens GELELEK: Forschungsziele und Ergebnisse N2 - Der Vortrag stellt das WIPANOForschungsvorhaben GELELEK vor und fasst die wichtigsten erzielten Ergebnisse zusammen. T2 - 13. Sitzung des GfKORR Arbeitskreises „Korrosionsuntersuchung und -überwachung“ CY - Online meeting DA - 08.12.2021 KW - Deckschichtbildung KW - Gelartige Elektrolyte KW - Korrosionsuntersuchungen KW - Normung KW - Ringversuch KW - Zink KW - WIPANO PY - 2021 AN - OPUS4-53946 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Babutzka, Martin T1 - New findings on the formation of corrosion product layers on zinc in the atmosphere N2 - The presentation shows systematic investigations to describe the corrosion and corrosion product formation processes of pure zinc under the climatic conditions currently prevailing in the Federal Republic of Germany. The investigations in their entirety aim at questioning current and establishing new ways of looking at the formation of corrosion products of pure zinc under atmospheric corrosion conditions. Thus, they make a significant contribution in understanding corrosion protection by zinc and zinc coatings. In particular, the focus is placed on the initial stage of the corrosion product formation. A systematic investigation of this time range, which is characterized by very reactive corrosion products, is only made possible by using gel-type electrolytes. The short periods of time at the beginning of weathering is now measurable and their influence on the formation of corrosion products and the kinetics of layer formation describable. By combining the new electrochemical approach with gravimetric, microscopic and analytical methods, new insights could be gained both on a methodic and scientific level. T2 - EUROCORR 2021 CY - Online meeting DA - 20.09.2021 KW - Atmospheric Corrosion KW - Corrosion KW - Corrosion products KW - Gel-type electrolytes KW - Zinc PY - 2021 AN - OPUS4-53332 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Babutzka, Martin T1 - Neue Erkenntnisse zur Deckschichtbildung von Zink an der Atmosphäre N2 - Die Untersuchungen und Ausführungen im Vortrag belegen, dass verfügbare Modellvorstellungen zur Beschreibung der Deckschichtbildung und Korrosion von Zink unter aktuellen atmosphärischen Bedingungen in Europa nicht mehr gültig sind und neu bewertet werden müssen. So können beispielsweise bisher verfügbare Prognosemodelle den Korrosionsfortschritt nicht mehr ausreichend beschreiben, da durch die Verringerung des Schwefeldioxidgehaltes der Luft veränderte Mechanismen vorliegen. T2 - Sitzung des Forschungsbeirats des Gemeinschaftsausschuss Verzinken e.V. CY - Online Meeting DA - 07.10.2021 KW - Atmosphärische Korrosion KW - Deckschichtbildung KW - Gelartige Elektrolyte KW - Zink PY - 2021 AN - OPUS4-53478 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Babutzka, Martin T1 - Vorstellung des WIPANO-Vorhabens GELELEK N2 - Der Vortrag stellt das WIPANO-Forschungsvorhaben GELELEK vor und fasst die wichtigsten erzielten Ergebnisse zusammen. T2 - Sitzung des Forschungsbeirats des Gemeinschaftsausschuss Verzinken e.V. CY - Online meeting DA - 07.10.2021 KW - Deckschichtbildung KW - Gelartige Elektrolyte KW - Korrosionsuntersuchungen KW - Normung KW - Ringversuch KW - Zink PY - 2021 AN - OPUS4-53479 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Erning, Johann Wilhelm T1 - Wie gehe ich bei einer Schadensuntersuchung vor? N2 - Die Vorgehensweise bei einer Schadensanalyse wird beschrieben. Hinweise zu Methodik, Fehlervermeidung und Verhalten werden gegeben. T2 - Der sichere Einsatz von Werkstoffen aus Kupfer und Kupferlegierungen in der Trinkwasserinstallation CY - Online meeting DA - 12.20.2021 KW - Schadensanalyse KW - Korrosion PY - 2021 AN - OPUS4-53518 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bäßler, Ralph T1 - Influence of Precipitating Brine Components on Materials Selection for Geothermal Applications N2 - By exposure and electrochemical tests in the laboratory the Cu- and Pb-effect on corrosion behavior and performance of carbon steel and a corrosion resistant alloy could be assessed. Critical material specific properties were determined by static exposure and electrochemical tests in artificial geothermal water with high salinity and low pH, containing Cu/Pb. It could be shown that significant Cu- resp. Pb-deposition and precipitation only occurred in combination with carbon steel. Corrosion resistant alloys (e. g. Cr- and Ni-dominated stainless steels) prevent the disturbing Cu-agglomeration resp. Pb-deposition. Therefore, they are suitable to be chosen for future design of geothermal piping system, either in massive or in cladded form. Regarding corrosion, formation of crevices with non-metallic materials shall be avoided. So, in addition to its already known limited corrosion resistance, carbon steel shall not be used when copper or lead species are content of the geothermal brine. Otherwise precipitation and/or deposition of metallic copper resp. lead must be expected, increasing the susceptibility of clogging the piping system. From the interactions and pitting corrosion point of view, corrosion resistant alloys (preferably Ni-rich) seem to be most favorable when selecting materials for applications in such geothermal brines. T2 - World Geothermal Congress CY - Online meeting DA - 15.06.2021 KW - Copper KW - Lead KW - Corrosion KW - Steel KW - Geothermal energy PY - 2021 AN - OPUS4-52829 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Babutzka, Martin T1 - Neue Erkenntnisse zur Deckschichtbildung von Zink an der Atmosphäre N2 - Die Untersuchungen und Ausführungen im Vortrag belegen, dass verfügbare Modellvorstellungen zur Beschreibung der Deckschichtbildung und Korrosion von Zink unter aktuellen atmosphärischen Bedingungen in Europa nicht mehr gültig sind und neu bewertet werden müssen. So können beispielsweise bisher verfügbare Prognosemodelle den Korrosionsfortschritt nicht mehr ausreichend beschreiben, da durch die Verringerung des Schwefeldioxidgehaltes der Luft veränderte Mechanismen vorliegen. T2 - Sitzung des GfKORR Arbeitskreises „Korrosion und Korrosionsschutz von Eisen und Stahl“ CY - Online meeting DA - 22.06.2021 KW - Atmosphärische Korrosion KW - Gelartige Elektrolyte KW - Deckschichtbildung KW - Zink PY - 2021 AN - OPUS4-52843 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bäßler, Ralph T1 - Study of Polyaniline/Silicon Dioxide based Coating on Carbon Steel in Artificial Geothermal Brine N2 - By using the available resources in Indonesia, such as silicon dioxide and marine coating base, the PANI/SiO2 modified alkyd coating was able to protect carbon steel in a deaerated artificial geothermal water. The screening of coatings shows that the modification by adding individual pigment was not sufficient to protect carbon steel even during a short-term exposure, indicated by the discoloration after only seven days of exposure. Electrochemical tests indicated that there was no significant change in the Ecorr between the coated and uncoated carbon steel at room temperature. At 150 °C, the coated carbon steel has a lower potential than that of carbon steel, indicating that the coating is protecting carbon steel cathodically or slowing down the corrosion reaction. Finally, a long-term exposure test confirmed that the PANI/SiO2 modified coating successfully protects the carbon steel in the Sibayak artificial geothermal water up to 150 °C for 6 months. T2 - World Geothermal Congress CY - Online meeting DA - 15.06.2021 KW - Coatings KW - Corrosion KW - Polyaniline KW - Sibayak KW - SiO2 KW - Geothermal PY - 2021 AN - OPUS4-52831 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kamaraj, Abinaya T1 - Susceptibility of 304 stainless steel to crevice corrosion in electrochemically active fluids N2 - The susceptibility of AISI 304 stainless steel to crevice corrosion on the effect of contact with electrochemically active fluids was investigated using exposure and stepwise potentiostatic polarisation. Crevice materials made up of 304 SS and Polyether ether ketone (PEEK) forming two kinds of crevices including 304 SS-to-PEEK and 304 SS-to-304 SS were tested. T2 - Corrosion 2019 NACE CY - Nashville, TN, USA DA - 24.03.2019 KW - Desinfection KW - Crevice corrosion KW - ECA PY - 2019 AN - OPUS4-49284 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Lehmann, Jens T1 - ISER Merkblatt 833 - Edelstahl Rostfrei in Erdböden - Aus Sicht des Korrosionsschutzes N2 - Der Einsatz von Edelstahl Rostfrei in Böden wird nur in wenigen Regelwerken behandelt, somit müssen sich Anwender und mPlaner auf Erfahruzngen und Studien stützen um Hilfestellung zum Beispiel zur Werkstoffauswahl zu erhalten. Der Vortrag stellt das von der BAM und der ISEr überarbeiteet Merkblatt 833 vor, welches den Einsatz von Edelstahl Rostfrei im Erdboden bahandelt. T2 - Informationsstelle Edelstahl Rostfrei - Kursleiter Fortbildung 2019 CY - Kalkar, Germany DA - 23.09.2019 KW - Nichtrostender Stahl KW - Korrosion KW - Erdboden PY - 2019 AN - OPUS4-49108 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Heise, Svenja T1 - Normentwurf für ein Prüfverfahren zur Bestimmung von Deckschichtwiderständen an Zinküberzügen mittels gelartiger Elektrolyte (WIPANO - GELELEK) N2 - Der Vortrag stellt das WIPANO-Vorhaben GELELEK vor. Zu Beginn wird die Problemstellung und Projektidee kurz erläutert. Anschließend wird ein Überblick über die Projektpartner, Projektziele und Arbeitsschritte gegeben, sowie die ausgewählten Probenbleche vorgestellt. Abschließend wurde noch eine Einladung zur Teilnahme am projektbegleitenden Ausschuss ausgesprochen. T2 - Sitzung des GAV-Forschungsbeirates CY - Iserlohn, Germany DA - 18.09.2019 KW - Deckschichtbildung KW - Gelartige Elektrolyte KW - Korrosion KW - Zinküberzüge PY - 2019 AN - OPUS4-49038 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bäßler, Ralph T1 - Components in CO2-stream, corrosive to Materials to be Used in CC(U)S Applications N2 - CO2 quality specifications are not only a matter of CO2 purity (i.e. CO2 content). The “rest” also matters, in particular contents of reactive impurities affecting material corrosion (and rock alteration). Also chemical reactions in CO2 stream needs to be considered, in particular when combining CO2 streams of different compositions. T2 - WCO Forum at AMPP Annual International Corrosion Conference 2021 CY - Online Meeting DA - 26.04.2021 KW - Carbon capture storage KW - Corrosion PY - 2021 AN - OPUS4-52502 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bäßler, Ralph T1 - Preliminary Study on Al2O3 Sol-Gel Coating for Corrosion Protection of Martensitic Stainless Steel in Artificial Geothermal Water N2 - Al2O3 coatings are often used as protective layers on steels against electrochemical and high-temperature corrosion because they are chemically inert and stable at elevated temperatures. This study presents preliminary work on the possibilities of using Al2O3 sol-gel coatings for corrosion protection of martensitic stainless steels in geothermal environments. Al2O3 sol-gel coatings were applied on UNS S42000, which is known to be susceptible to uniform and localized corrosion. The coated steel specimens were then tested in two types of artificial geothermal water, which simulate the geothermal fluids found in Sibayak (SBY), Indonesia, and North German Basin (NGB), Germany, respectively. SBY has pH 4 and 1.5 g/L of chloride ions, whereas NGB has a pH of 6 and 166 g/L of chloride ions. All experiments were carried out in autoclaves at 150 °C and 1 MPa under the deaerated condition. Evaluations were performed by investigating the surface profiles of both uncoated and coated steels before and after the corrosion test using a Laser Scanning Microscope (LSM) and Scanning Electron Microscope (SEM). Finally, Electrochemical Impedance Spectroscopy (EIS) was performed to compare the corrosion resistance of Al2O3 coated steels in SBY and NGB solutions. It was observed from the corrosion test that Al2O3 coatings are more suitable for use in the geothermal water with a higher pH. T2 - AMPP Annual International Corrosion Conference 2021 CY - Online Meeting DA - 19.04.2021 KW - Protective coating KW - Sol-gel coating KW - Geothermal KW - Martensitic steel KW - Corrosion PY - 2021 AN - OPUS4-52500 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rütter, H. T1 - Combining CO2 streams from different emitters ‐ a challenge for pipeline transportation N2 - Depending on the CO2 generating and the capture process as well as on consecutive purification steps applied, CO2 streams from different emitters may differ in their composition. When CO2 streams with different compositions are fed into a larger pipeline network, there are several aspects that must be considered: i) chemical reactions, such as acid formation, may occur within the joint CO2 stream; ii) there may be a variation of mass flow rate and CO2 stream composition within the pipeline network if the feed-in behavior of different CO2 sources changes with time. Potential impacts of changing CO2 stream compositions and mass flow rates in CCS cluster systems were investigated in the collaborative project "CLUSTER" (see also www.bgr.bund.de/CLUSTER). In this presentation, we focus on the experimental investigations of formation and condensation of strong acids and their impacts on the corrosion of pipeline steels. When SO2, NO2, O2 and H2O are present simultaneously in CO2 streams chemical cross-reactions may occur leading to the formation of strong acids such as sulfuric and nitric acid. To prevent this acid formation the concentration of at least one of these four impurities must be kept very low (e.g., Rütters et al., 2016). At temperatures below the acid dew point temperature, acids will condense, e.g., on pipeline steel surfaces. In turn, these acid condensates may trigger steel corrosion. To better understand the process of acid formation and condensation and its implications for steel corrosion, exposure tests were performed on pipeline steel X70 in dense CO2 with varying SO2, NO2 and O2 concentration under high pressure and at 278 K in an observable autoclave, in which water was added as droplets or as vapor. Further, electrochemical tests were carried out with X70 specimens immersed in 500 mL CO2-saturated synthetic condensate solution or in droplets of the same solution on the specimen’s surface. Depending on impurity concentrations in the CO2 streams, condensates consisting of different relative amounts of nitric and sulfuric acid were formed. In condensates containing both nitric and sulfuric acid, corrosion rates were higher than the sum of those of the individual acids. In addition, corrosion products and forms depended on the condensate composition. Investigations of water droplets on steel surfaces in impurity-containing dense-phase CO2 revealed the diffusion of SO2 and NO2, followed by cross-reactions forming corresponding acids. An increase in droplet size (from 1 to 5 µl) lead to higher corrosion rates. However, in comparison to measurements in bulk solution, corrosion reactions in droplets resulted in thick, high-resistance corrosion products and observed droplet corrosion rates were significantly lower. In addition, the possibility of acid droplet formation and growth in impure liquid CO2 is influenced by the wetting behavior of the acid droplet on the steel surface. Thus, the contact angle between a water droplet and the surface steel specimens in a CO2 atmosphere was investigated in a high pressure view cell following the sessile drop method. The contact angle wasand found to be larger at higher CO2 pressures (studied from 5 to 20 MPa) and at higher temperatures (e.g. 278 K to 333 K). Further, measured contact angles were larger on rough than on smooth metal surfaces. In addition, acid formation reduced the contact angle, i.e. lead to better wetting, thereby stimulating condensation that was followed by a corrosion process. These detailed insights on the complex interplay of acid formation, condensation, wetting behavior and corrosion allow a better assessment of material suitability for pipeline transportation of impure CO2 streams T2 - TCCS-10 The 10th Trondheim Conference on Carbon Capture, Transport and Storage CY - Trondheim, Norway DA - 17.06.2019 KW - arbon capture KW - utilization, and storage (CCUS) technology KW - corrosion KW - condensate KW - electrochemical characterization KW - pitting corrosion KW - impurities KW - carbon steel PY - 2019 UR - https://www.sintef.no/globalassets/project/tccs-10/dokumenter/tccs10---book-of-abstracts.pdf AN - OPUS4-48369 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Burkert, Andreas T1 - Normentwurf für ein Prüfverfahren zur Bestimmung von Deckschichtwiderständen an Zinküberzügen mittels gelartiger Elektrolyte (WIPANO – GELELEK) N2 - Der Vortrag stellt das WIPANO-Vorhaben GELELEK vor. Zu Beginn werden die Messtechnik und die Projektidee kurz erläutert. Anschließend wird ein Überblick über die Projektpartner, Projektziele und Arbeitsschritte gegeben. T2 - Arbeitskreissitzung des DIN-Arbeitskreises NA 062-01-77 AA „Korrosionsprüfverfahren“ CY - Neuss, Germany DA - 24.10.2019 KW - Deckschichtbildung KW - Gelartige Elektrolyte KW - Korrosion KW - Zinküberzüge PY - 2019 AN - OPUS4-49411 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Burkert, Andreas T1 - Korrosionsverhalten von Zink unter atmosphärischen Einsatzbedingungen N2 - Der Vortrag stellt aktuelle Frage- und Problemstellungen bei der atmosphärischen Korrosion von Zink vor, die aus der Anwendung der relevanten Normen resultieren. T2 - Arbeitskreissitzung des DIN-Arbeitskreises NA 062-01-71 AA „Korrosion und Korrosionsschutz“ CY - Neuss, Germany DA - 23.10.2019 KW - Deckschichtbildung KW - Korrosion KW - Zink PY - 2019 AN - OPUS4-49410 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Lin, Xuebao T1 - Weathering Resistance of Halogen-free Flame Retardance in E&E Polymeric Materials N2 - Nowadays, various polymeric materials are used in E&E applications with sufficient flame retardance by adding rather different flame retardants. It doesn’t matter whether cables are used outdoor or are installed indoor as building products, the weathering exposures such as UV radiation, humidity and variation in temperature occur and influence the flame-retardant property. Recently, the lifetime of the flame retardance itself becomes an increasingly important factor. In this work, several devices were used to perform accelerated artificial ageing simulating different environment exposures. The comprehensive and global understanding of the durability of flame retardance in dependence on the weathering or ageing conditions is still a matter of discussion. Therefore, the weathering resistance of various halogen-free fire-retarded polymers was investigated in this work. Polymeric systems with different kinds of fire retardants were chosen, including various fire retardant mechanisms. Ethylene Vinyl Acetate (EVA) blends with high amounts of inorganic flame retardant such as aluminum hydroxide (ATH), boehmite and synergists, which mainly dilutes the polymer resin work as heat sink and cooling agent, and enhance residue formation was examined. Thermoplastic Polyurethane (TPU) was modified with melamine cyanurate (MC), which mainly acts by changed melt flow and dripping behavior as well as fuel dilution. Additionally, aluminum diethylphosphinate and boehmite are induced as assistant flame retardant. Furthermore, glass fiber reinforced Polyamide 66 (PA) was investigated containing different kinds of aluminum diethylphosphinate based flame retardant mixtures, which acts by flame inhibition and additional char formation. The degradation of the surface was analyzed after the different weathering conditions. Most of the specimens exhibited an intensive material degradation at the top surface accompanied by a distinct discoloration, e.g. getting darker or showing yellowing. The weathering of the EVA samples lead to numerous cracks (already) after 4000 h. The corresponding changes in the chemical structure was investigated by ATR FT-IR for all materials. The flammability was investigated by cone calorimeter, UL-94 burning chamber, and oxygen index (LOI) using plate and bar specimens. The flame retardance of most of the materials studied degrades only slightly or were rather stable for the investigated exposure times. Interestingly, also some opposite results were found. EVA modified by different inorganic flame retardants such as ATH achieved higher LOI after exposing in the humidity chamber and the accelerated oxidation under water in the autoclaves. It is suggested that the particle size of ATH and boehmite plays an important role, when these flame retardants agglomerate at the surface during accelerated weathering. Both materials, EVA and TPU, were also investigated as cable jackets. While EVA modified with inorganic flame retardants exhibits low-smoke and non-dripping fire behavior, TPU flame-retarded with MC yields cables with pronounced melt-dripping. Cone calorimeter tests were carried out using cable rafts of the size of 100 mm * 100 mm as well as our self-made cable module test, which simulates the vertical full-scale test of a bundle of cables at the bench-scale. Both methods were used to investigate the weathering resistance of the flame retardance in cables. The results of the cable module test for the flame-retarded EVA cables were only slightly affected even when a long time hydrothermal ageing was carried out. This is because of inorganic residue which just delays the fire growth but does not extinguish. However, for the flame-retarded TPU cable jackets, the cable module test exhibited an accelerated fire spread and a melt-dripping behavior which was promoted by weathering exposure. T2 - FRPM 2019, 17th European Meeting on Fire Retardant Polymeric Materials CY - Turku, Finland DA - 26.06.2019 KW - Cable KW - Flame retardant KW - Weathering resistance KW - Durability KW - ethylene vinyl acetate KW - Thermoplastic polyurethane KW - Flammability PY - 2019 AN - OPUS4-48553 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Le, Quynh Hoa T1 - On the corrosion behaviour of CO2 injection pipe steels: Role of cement N2 - Carbon Capture and Storage (CCS) is identified as an excellent technology to reach the target of CO2 reduction. However, the safety issue and cost-effectiveness hinder the future of CCS. For the reliability and safety issues of injection wells, the corrosion resistance of the materials used needs to be determined. In this study, representative low-cost materials including carbon steel 1.8977 and low alloyed steel 1.7225 were investigated in simulated pore water at 333 K and under CO2 saturation condition to represent the worst-case scenario: CO2 diffusion and aquifer fluid penetration. These simulated pore waters were made from relevant cement powder to mimic the realistic casing-cement interface. Electrochemical studies were carried out using the pore water made of cement powder dissolved in water in comparison with those dissolved in synthetic aquifer fluid, to reveal the effect of cement as well as formation water on the steel performance. Two commercially available types of cement were investigated: Dyckerhoff Variodur® and Wollastonite. Variodur® is a cement containing high performance binder with ultra-fine blast furnace slag which can be used to produce high acid resistance concrete. On the other hand, Wollastonite is an emerging natural material mainly made of CaSiO3 which can be hardened by converting to CaCO3 during CO2 injection. The results showed the pH-reducing effect of CO2 on the simulated pore water/aquifer (from more than 10 to less than 5) leading to the active corrosion process that happened on both 1.8977 and 1.7225. Electrochemical characterization showed negative free corrosion potential and polarisation curves without passive behaviors. The tested coupons suffered from pitting corrosion, which was confirmed by surface analysis. Interestingly, basing on the pit depth measurements from the tested coupons and the hardness of cement powder, it is suggested that Variodur® performed better than Wollastonite in both aspects. The electrochemical data was compared to that resulted from exposure tests to give a recommendation on material selection for bore-hole construction. T2 - EUROCORR 2019 CY - Sevilla, Spain DA - 09.09.2019 KW - Carbon capture KW - Utilization, and storage (CCUS) technology KW - Corrosion KW - Carbon steel KW - Mortel KW - Crevice corrosion PY - 2019 AN - OPUS4-49105 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Babutzka, Martin T1 - Beschreibung der Deckschichtbildung bei Zink und Zinklegierungen mittels minimalinvasiver Korrosionsuntersuchungen und analytischer Methoden (MINIMAL) N2 - Der Vortrag stellt ein neuartiges Korrosionsprüfverfahren für Zinküberzüge auf Basis gelartiger Elektrolyte vor und führt die Vorteile gegenüber konventionellen Prüfverfahren auf. Basierend auf den Ergebnissen wird die Idee für einen IGF-Projektantrag in Kooperation mit dem Fraunhofer IKTS vorgestellt. T2 - Sitzung des GAV-Forschungsbeirates CY - Iserlohn, Germany DA - 18.09.2019 KW - Deckschichtbildung KW - Gelartige Elektrolyte KW - Korrosionsprüfung KW - Zinkdeckschichten KW - Corrosion testing KW - Gel-type electrolytes KW - Layer formation KW - Zinc coatings PY - 2019 AN - OPUS4-49036 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Markwart, J. C. A1 - Battig, Alexander A1 - Urbaniak, T. A1 - Haag, K. A1 - Koschek, K. A1 - Schartel, Bernhard A1 - Wurm, F. R. T1 - Intrinsic flame retardant phosphonate-based vitrimers as a recyclable alternative for commodity polymers in composite materials N2 - Recycling of crosslinked fiber-reinforced polymers is difficult. Moreover, as they are often based on flammable resins, additional additives are needed. So-called “vitrimers” open the possibility of Recycling and reprocessing and repairing with dynamically crosslinked chemistries. To date, vitrimer-based composites still need flame retardant additives, such as organophosphates. An additive-free vitrimer composite has not been reported. Herein, we synthesized an intrinsic flame-retardant vitrimer, relying on vinylogous polyurethanes containing covalently installed phosphonates as flame-retardant units and prepared glassfiber-reinforced composites. We studied recycling and flame retardant properties and compared the data to phosphorus-free vitrimers and conventional epoxy resins (with and without additive flame retardant). Our phosphonate-based vitrimer proved in first tests, a flame retardant effect comparable to commercial flame retardant resins. The bending strength and bending modulus for the phosphorus-vitrimer glass fiber composites were comparable to glass fiber composites with permanently cross-linked epoxies. In summary, we were able to prove that the covalent installation of phosphonates into vitrimers allows the preparation of recyclable and intrinsic flame retardant composites that do not need flame retardant additives. We believe this concept can be expanded to other polymer networks and additives to generate recyclable and sustainable high-performance materials. KW - Vitrimer KW - Flame retardant KW - Recyclable KW - Organophosphonate KW - Polyurethane PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-510889 DO - https://doi.org/10.1039/d0py00275e VL - 11 IS - 30 SP - 4933 EP - 4941 AN - OPUS4-51088 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hille, Falk A1 - Sowietzki, D. A1 - Makris, R. T1 - Luminescence-based early detection of fatigue cracks N2 - Classic non-destructive fatigue crack detection methods reveal the state of the fatigue damage evolution at the moment of application, generally not under operational conditions. The here introduced crack luminescence method realizes a clear visibility of the occurred and growing crack in loaded components during operation. Different established experiments show that due to the sensitive coating a crack Formation can be detected even in early stage under the premise the crack reached the surface. The coating consists of two layers with different properties and functions. The bottom layer emits light as fluorescence under UV radiation. The top layer covers the fluorescing one and prevents the emitting of light in case of no damage at the surface. In case of surface crack occurrence, the luminescent light is clearly noticeable by visual observations and also by standard camera equipment which makes automated crack detection possible as well. It is expected that crack luminescence can increase structural safety as well as reduce costs and time for inspections and preventive maintenance. KW - Coating KW - Fatigue KW - Crack damage detection KW - Luminescence PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-510517 DO - https://doi.org/10.1016/j.matpr.2020.02.338 SN - 2214-7853 SP - 1 EP - 5 PB - Elsevier CY - Amsterdam AN - OPUS4-51051 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Burkert, Andreas A1 - Lehmann, Jens T1 - Einfach und doch speziell - Das Korrosionsverhalten nichtrostender Stähle N2 - In diesem zweiten Teil wird das spezielle Korrosionsverhalten nichtrostender Stähle vorgestellt. T2 - ISER Kursleiterfortbildung 2022 CY - Düsseldorf, Germany DA - 26.09.2022 KW - Korrosion KW - Elektrochemie KW - Experimentalvortrag PY - 2022 AN - OPUS4-55857 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Burkert, Andreas A1 - Lehmann, Jens T1 - Einfach und doch komplex - Korrosion metallener Werkstoffe N2 - In diesem Teil 1 werden die Grundlagen der Korrosion für metallene Werkstoffe zusammengefasst. T2 - ISER Kursleiterfortbildung 2022 CY - Düsseldorf, Germany DA - 26.09.2022 KW - Korrosion KW - Elektrochemie KW - Experimentalvortrag PY - 2022 AN - OPUS4-55855 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Babutzka, Martin T1 - New findings on the formation of corrosion product layers on zinc in the atmosphere N2 - The presentation shows systematic investigations to describe the corrosion and corrosion product formation processes of pure zinc under the climatic conditions currently prevailing in the Federal Republic of Germany. The investigations in their entirety aim at questioning current and establishing new ways of looking at the formation of corrosion products of pure zinc under atmospheric corrosion conditions. Thus, they make a significant contribution in understanding corrosion protection by zinc and zinc coatings. In particular, the focus is placed on the initial stage of the corrosion product formation. A systematic investigation of this time range, which is characterized by very reactive corrosion products, is only made possible by using gel-type electrolytes. The short periods of time at the beginning of weathering is now measurable and their influence on the formation of corrosion products and the kinetics of layer formation describable. By combining the new electrochemical approach with gravimetric, microscopic and analytical methods, new insights could be gained both on a methodic and scientific level. T2 - 2nd Task Group Meeting TC124 WG4-TC 250 SC5 Task Group Corrosion CY - Online Meeting DA - 06.05.2021 KW - Zinc KW - Corrosion products KW - Gel-type electrolytes KW - Corrosion KW - Atmospheric corrosion PY - 2021 AN - OPUS4-52604 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Babutzka, Martin T1 - Vorstellung des Forschungsvorhabens GELELEK N2 - Der Vortrag stellt das Forschungsvorhaben GELELEK im Rahmen der Ad hoc Gruppe "GELELEK" des DIN-Normenausschusses Materialprüfung (NMP) vor. T2 - Sitzung der Ad hoc Gruppe "GELELEK" im DIN-Normenausschuss Materialprüfung (NMP) CY - Online Meeting DA - 21.04.2021 KW - Deckschichtbildung KW - Gelartige Elektrolyte KW - Korrosionsuntersuchungen KW - Zink PY - 2021 AN - OPUS4-52541 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kotula, Stefan T1 - Messsystemanalyse („Ringversuch“) zu WIPANO-Vorhaben „GELELEK“ N2 - Der Vortrag stellt die anstehende Messsystemanalyse im Rahmen der Ad hoc Gruppe "GELELEK" des DIN-Normenausschusses Materialprüfung (NMP) vor und erläutert die notwendigen Schritte zur erfolgreichen Durchführung. T2 - Sitzung der Ad hoc Gruppe "GELELEK" im DIN-Normenausschuss Materialprüfung (NMP) CY - Online Meeting DA - 21.04.2021 KW - Deckschichtbildung KW - Gelartige Elektrolyte KW - Korrosionsuntersuchungen KW - Zink KW - Normung KW - Messsystemanalyse PY - 2021 AN - OPUS4-52542 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Seher, Julia T1 - Lightweight Aggregates - Recycling of Construction and Demolition Waste N2 - A brief introduction into the production of lightweight aggregates from construction and demolition waste and some results of the project HYTEGRA. T2 - Postdoc Symposium: BAM Focus Area Material CY - Online meeting DA - 28.04.2021 KW - Leichte Gesteinskörnung KW - Rohstoffliches Recycling KW - Reststoffe KW - Mauerwerkbruch KW - Papierasche KW - Speichermaterial PY - 2021 AN - OPUS4-52606 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Stelzner, Ludwig T1 - Explosionsartiges Abplatzen gefügedichter Betone im Brandfall N2 - Beton, der heutzutage meist verwendete Baustoff, weist neben gutem Festigkeits- und Dauerhaftig-keitsverhalten ebenfalls erhöhte Brandschutzeigenschaften auf. Jedoch zeigen zahlreiche Schadensfälle, dass vor allem gefügedichte Betone im Brandfall zu explosionsartigen Abplatzungen neigen. Diese führen zum Freilegen der vorhandenen Stahlbewehrung und zur Verminderung des tragfähigen Bauteilquer-schnitts. Das wiederum kann im schlimmsten Fall eine Gefährdung der Standsicherheit eines Bauwerks zur Folge haben. Nach derzeitigem Stand werden die explosionsartigen Abplatzungen auf thermomechanische und thermohydraulische Prozesse zurückgeführt. Letztere beruhen auf der Generierung hoher Wasserdampfdrücke in einseitig brandbeanspruchten Betonbauteilen, die zum einen auf die geringe Permeabilität des hochfesten Betons und zum anderen auf die Bildung einer wassergesättigten Zone, der sogenannten „moisture clog“ zurückzuführen sind. Die experimentelle Analyse der dabei ablaufenden Feuchtetransport- und Feuchteumlagerungsmechanismen ist Gegenstand des Vortrags. Dazu wurde an der BAM im Rahmen eines MI-Typ 2 Projektes (FB 7.1, 7.3, 8.5) ein Versuchsstand aufgebaut, der die dreidimensionale, simultane Analyse und Quantifizierung des Feuchtetransports an einsei-tig erwärmten, miniaturisierten Prüfkörpern aus gefügedichtem Beton mittels Röntgencomputertomographie erstmals ermöglicht. Zusätzlich wird die eindimensionale Feuchteverteilung im Prüfkörper mittels Nuclear Magnetic Resonance (NMR) Technik vor und nach einseitiger Erwärmung untersucht. Mithilfe dieser Prüfmethodologie ist es möglich, die Ausbildung einer Trocknungs- bzw. Dehydrationszone sowie einer tiefergelegenen Feuchteakkumulationszone zeitlich aufgelöst abzubilden. Darüber hinaus können die Einflüsse einer Polypropylenfaserzugabe auf den thermisch induzierten Feuchtetransport quantifiziert werden. T2 - Abteilungs-Vortragsseminar CY - Berlin, Germany DA - 30.04.2019 KW - Explosionsartiges Abplatzen KW - Moisture clog KW - X-ray-CT KW - 1H-NMR KW - High-performance concrete PY - 2019 AN - OPUS4-48729 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Metz, Christian T1 - Untersuchung der Beständigkeit additiv gefertigter Bauteile mit Thermografie nach künstlicher Bewitterung N2 - Additiv gefertigte Prüfkörper aus Polyamid 12 (Laser Sinter Verfahren) und Acrylnitril-Butadien-Styrol (Fused Layer Modeling Verfahren) wurden über 2000 Stunden künstlich bewittert und ihr Alterungsverhalten untersucht. Die Ergebnisse wurden anschließend mit denen von Prüfkörpern verglichen, welche auf dieselbe Weise künstlich bewittert, aber mittels konventionellem Kunststoff-Spritzguss hergestellt wurden. Die Erkenntnisse dienen für die Entwicklung einer Strategie für eine Qualitätskontrolle von additiv gefertigten Kunststoffteilen. T2 - 48. Jahrestagung der Gesellschaft für Umweltsimulation e.V. (GUS) CY - Stutensee-Blankenloch, Germany DA - 27.03.2019 KW - Additive Fertigung KW - Künstliche Bewitterung KW - Thermografie KW - Zerstörungsfreie Prüfung KW - Additive manufacturing KW - Kunststoffe PY - 2019 AN - OPUS4-48328 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Babutzka, Martin T1 - Auslagerungsversuche von Reinzink-Standardproben unter verschiedenen atmosphärischen Bedingungen und in Straßentunneln N2 - Der Vortrag berichtet über die Auslagerung von Standardproben nach DIN EN ISO 9223 bis 9226 aus Zink, Stahl, Kupfer und Aluminium auf den verschiedenen atmosphärischen Bewitterungsständen der Bundesanstalt für Materialforschung und -prüfung (BAM). Im Vortrag werden die Masseverluste, Korrosionsgeschwindigkeiten und Korrosivitätskategorien der Standardproben im freibewitterten und überdachten Bereich nach einem Jahr vorgestellt und Unterschiede hinsichtlich der Atmosphärenbedingungen aufgezeigt. Freibewitterte Proben zeigen dabei deutliche Unterschiede hinsichtlich ihres Korrosionsverhaltens im Vergleich zu überdachten Proben. Die ermittelten Korrosivitätskategorien sind sowohl standort- als auch materialspezifisch. T2 - 11. Arbeitskreissitzung „Zink und Zinküberzüge“ des GfKORR e. V. CY - Frankfurt a. M., Germany DA - 03.07.2019 KW - Atmosphärische Korrosion KW - Auslagerungsversuche KW - Freibewitterung KW - Korrosion PY - 2019 AN - OPUS4-48406 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Babutzka, Martin T1 - Auslagerungsversuche von Standardproben unter verschiedenen atmosphärischen Bedingungen N2 - Der Vortrag berichtet über die Auslagerung von Standardproben nach DIN EN ISO 9223 bis 9226 aus Zink, Stahl, Kupfer und Aluminium auf den verschiedenen atmosphärischen Bewitterungsständen der Bundesanstalt für Materialforschung und -prüfung (BAM). Im Vortrag werden die Masseverluste, Korrosionsgeschwindigkeiten und Korrosivitätskategorien der Standardproben im freibewitterten und überdachten Bereich nach einem Jahr vorgestellt und Unterschiede hinsichtlich der Atmosphärenbedingungen aufgezeigt. Freibewitterte Proben zeigen dabei deutliche Unterschiede hinsichtlich ihres Korrosionsverhaltens im Vergleich zu überdachten Proben. Die ermittelten Korrosivitätskategorien sind sowohl standort- als auch materialspezifisch. T2 - Arbeitskreissitzung „Eisen und Stahl“ des GfKORR e. V. CY - Duisburg, Germany DA - 26.06.2019 KW - Atmosphärische Korrosion KW - Auslagerungsversuche KW - Freibewitterung KW - Korrosion PY - 2019 AN - OPUS4-48344 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - von Werder, Julia T1 - Internal sulfate resistance of concrete N2 - If the amount of sulfate within the mix design for concrete is not balanced, ettringite formation which first controls solidification continues while the concrete is hardening. Ettringite forms by reaction of sulfate contained in the cement or in some admixture with calcium aluminate (C3A) as cement component. The “late primary ettringite formation” promotes an increase in volume within the hardened concrete leading to cracks. To analyze the effect of substituting part of ordinary Portland cement (OPC) by a treated brown coal fly ash mortar bars were tested according to ASTM C452. This test method was originally developed to extrapolate from the internal to external sulfate attack and is based on the idea that by testing a concrete mixture containing sulfate the process of deterioration is accelerated because it does not have to diffuse into the concrete before reaction first. In addition to the samples prescribed in ASTM C452 further samples in the size of the German SVA procedure were tested also designed for accessing the external sulfate resistance. The results show that while the replacement of 25 % of cement by brown coal fly ash leads to length changes around the limit defined by ASTM, the substitution of 50 % cement exceeded the limit by a multiple. The progress of expansion is the very similar for the two geometries tested. In-situ XRD measurements confirmed that while for pastes made of OPC the formation of ettringite is completed after 20 hours, this is not true for the mixtures containing the brown coal fly ash. In a different study the effect of hydrothermal treatment on the phase composition of ultra-high-performance concrete was analyzed. The results show that the sulfate and aluminate resulting from the decomposition of ettringite are bound into new phases. If this binding is permanent this might allow the larger use of sulfate bearing raw materials. T2 - EuroCoalAsh 2021 Conference CY - Online meeting DA - 02.11.2021 KW - Brown coal fly ash KW - Ettringite KW - Internal sulfate resistance KW - Test methods KW - In-situ XRD KW - Hydrothermal treatment PY - 2021 AN - OPUS4-54134 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Koerdt, Andrea T1 - Mikrobielle Zusammensetzung im Wassertank N2 - Der Fachbereich 7.6 untersucht seit einiger Zeit an Auslagerungsständen auf dem Testgelände in Horstwalde Korrosion im maritimen Bereich. Im Moment läuft das System mit künstlichem Meerwasser und simuliert die Bewitterung von Metallproben unter angenäherten klimatischen Bedingungen ähnlich zum natürlichem Habitat. Im Laufe der Zeit konnte nicht intendierter mikrobieller bewuchs beobachtet werden. Es stellte sich die Frage, welche Mikroorganismen vorlagen und ob diese einen Einfluss auf die Korrosionsuntersuchungen haben könnte. Aus diesem Grund wurden 16S-rRNA Untersuchungen durchgeführt welche alle drei Domänen des Lebens widerspiegeln Bakterien, Archaea und Eukaryoten. Es konnte gezeigt werden, dass über 95% der vorliegenden Biomasse Grünalgen waren, die durch Licht Eintrag in den Container Photosynthese betrieben und dadurch an Biomasse zunahmen. Des weiteren konnten Bakterien detektiert werden, welche in der Regel halophilen und aeroben Habitaten zu finden sind. Allerdings wurden auch Sulfat reduzierende Bakterien (MIC) detektiert, wenn auch in einem geringen prozentualen Anteil. Es muss allerdings Berücksichtigt werden, dass die mikrobielle Zusammensetzung sich im Laufe der Zeit weiter ändern kann. Als Ursprung der Biomasse wird, das künstliche Sediment vermutet. Außerdem wäre es für zukünftige Experiment denkbar, das System mit echtem Sediment aus dem marinen Habitat anzuimpfen. T2 - Dechema CY - Online meeting DA - 10.11.2021 KW - Mikroorganismen KW - Mikrobielle Gemeinschaft KW - Korrosion KW - Simulation PY - 2021 AN - OPUS4-54035 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Wachtendorf, Volker T1 - Untersuchung der Witterungsbeständigkeit komplexer Funktionalitäten von Polymerwerkstoffen durch künstliche Bewitterung: Flammschutz N2 - In den letzten Jahrzehnten wurde die Degradation der polymeren Matrix von flammgeschützten Polymeren eingehend untersucht. Erst in den letzten Jahren jedoch hat sich die Frage der Lebensdauer der Funktionalität des Flammschutzes selbst als wichtige Fragestellung herauskristallisiert, z.B. bei Kabeln. Deshalb sollte diese Fragestellung durch systematisch-variierte künstliche Klima- und Bewitterungstests an flammgeschützten Polymerwerkstoffen untersucht werden T2 - 50. Jahrestagung der Gesellschaft für Umweltsimulation (GUS) CY - Online meeting DA - 23.03.2022 KW - Flammschutz KW - Witterungsbeständigkeit KW - Langzeitbeständigkeit KW - UV KW - E&E PY - 2022 AN - OPUS4-54541 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bäßler, Ralph T1 - Evaluation of Corrosion Resistance of Metallic Materials in Geothermal Applications N2 - Evaluation of corrosion resistance of metallic materials is essential to assure safe and reliable operation of geothermal sites. One need to be aware that corrosion is not a material's but a system property, determined by medium, material and construction aspects. Various corrosion types have to be evaluated. Conditions in laboratory shall reflect on-site reality. Depending on brine composition and temperature suitability of metallic materials can be ranked. Most important outcome of the research is that highly saline geothermal brines require high alloyed materials, for safe long-term operation. T2 - Geothermal Essentials - Moving Geothermal Forward in Canada: Scaling and Corrosion (Surface Facilities) CY - Online Webinar DA - 16.03.2022 KW - Corrosion KW - Geothermal KW - Steel PY - 2022 AN - OPUS4-54482 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Battig, Alexander A1 - Abdou-Rahaman Fadul, Naïssa A1 - Frasca, Daniele A1 - Schulze, Dietmar A1 - Schartel, Bernhard T1 - Multifunctional graphene nanofiller in flame retarded polybutadiene/chloroprene/carbon black composites N2 - To curtail flammability risks and improve material properties, flame retardants (FRs) and fillers are mixed into rubbers. High loadings of aluminum trihydroxide (ATH) and carbon black (CB) are the most used FRs and reinforcing additive, respectively, in rubbers. To reduce loading without losing mechanical properties, partial substitution of ATH as well as CB by low amounts of multilayer graphene (MLG) nanoparticles is investigated. The high aspect ratio MLG is made of ten graphene sheets. In polybutadiene/chloroprene (BR/CR) nanocomposites 3 phr MLG replaced 15 phr CB and/or 3 phr ATH. Material and mechanical properties as well as fire behavior of the nanocomposites are compared to BR/CR with 20 phr CB both with and without 50 phr ATH. MLG appears as a promising nanofiller to improve the functional properties: replacement of CB improved rheological, curing, and mechanical properties; substitution of ATH improved nanocomposite properties without affecting flame retardancy. KW - Nanocomposites KW - Rubber KW - Multilayer graphene KW - Carbon black KW - Polybutadiene/chloroprene KW - Graphene PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-523468 DO - https://doi.org/10.1515/epoly-2021-0026 SN - 1618-7229 VL - 21 IS - 1 SP - 244 EP - 262 PB - De Gruyter AN - OPUS4-52346 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schartel, Bernhard T1 - Bio, Waste, Non-vegan – Fun, Food for Thought, or Future N2 - Overview of the state of the art and current trends with the main topics: - renewable sources in flame retardant polymers (flame retarded bio-polymers and biocomposites; bio-flame retardants, renewable adjuvants from industrial waste) - flame retardancy meets sustainability - concepts between analogy and out-of-the-box. T2 - 18th SKZ International Conference on Trends in Fire Safety and InnovativeRFlame retardants for Plastics CY - Würzburg/Rottendorf, Germany DA - 27.09.2022 KW - Bio-polymer KW - Bio-composite KW - Renewable source KW - Renewable adjuvants KW - Vitrimer KW - Bio-flame retardant PY - 2022 AN - OPUS4-55840 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Lehmann, Jens T1 - ISER Merkblatt 833 - Edelstahl Rostfrei in Erdböden - Aus Sicht des Korrosionsschutzes N2 - Besonderheiten bei der Korrosion in Böden. Relevante Korrosionsarten für nichtrostende Stähle im Bodenkontakt. Regelwerke und Normen für die Anwendung nichtrostender Stähle in Böden. Erfahrungen und Studien zum Themenkomplex. Korrosionsrelevante Inhalte des MB 833. T2 - Informationsstelle Edelstahl Rostfrei - Marketing Sitzung CY - Düsseldorf, Germany DA - 02.05.2019 KW - Nichtrostender Stahl KW - Korrosion KW - Erdboden PY - 2019 AN - OPUS4-47926 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Burkert, Andreas T1 - Korrosionsschutz durch Deckschichtbildung und Passivität N2 - Metallene Konstruktionswerkstoffe reagieren infolge ihres thermodynamisch instabilen Zustandes mehr oder weniger stark mit Stoffen aus der Umgebung. Eine große Rolle bei diesen Reaktionen spielt das Feuchtigkeitsangebot an der Metalloberfläche, welches nicht zwingend mit einem sichtbaren Wasserfilm einhergehen muss. An der Atmosphäre bilden sich an sauberen Metalloberflächen bei etwa 80 % relativer Luftfeuchte, bei versalzten Oberflächen auch schon ab etwa 25 % r. F., Feuchtfilme aus. Im Feuchtfilm laufen grundsätzlich die gleichen elektrochemischen Reaktionen ab, wie diese von wässrigen Medien bekannt sind. Dabei geht das Metall zunächst in Ionenform und in nachgelagerten Reaktionen in einen thermodynamisch stabilen Zustand in Form unterschiedlichster Oxid- und Hydroxidverbindungen über. Die so entstehenden Korrosionsprodukte können im Feuchtigkeitsfilm begrenzt löslich oder unlöslich sein und lagern sich auf den Oberflächen der Konstruktionswerkstoffe häufig als feste Korrosionsprodukte ab bzw. wachsen dort auf. Je nachdem wie die Korrosionsprodukte strukturell zum Untergrund passen, können sich dichte, sehr gut haftende Schichten ausbilden oder poröse, dicke Schichten ohne nennenswerte Haftung aufwachsen. Wachsen dichte, porenfreie Schichten mit guter Haftung auf, die im umgebenden Medium unlöslich sind, wird die weitere Auflösung des Metalls stark gehemmt. Man spricht dann von der Ausbildung schützender Deckschichten bzw. von Passivschichten auf welcher der Korrosionsschutz und damit die Dauerhaftigkeit vieler Konstruktionswerkstoffe beruhen. Kaesche bezeichnete die Passivität sehr treffend als „optimalen Grenzfall des Korrosionsschutzes durch Schichten von Korrosionsprodukten“. Aus technischer Sicht hält Kaesche eine Unterscheidung von Deckschichten bzw. Passivschichten für nicht zwingend erforderlich, da beide die Korrosionsgeschwindigkeit in gleichem Maß herabsetzen können. Die Übergänge zwischen den meist dickeren und dadurch sichtbaren Deckschichten und den meist dünnen, nicht sichtbaren Passivschichten sind fließend. T2 - 18. Tagung "Korrosionsschutz in der maritimen Technik" CY - Hamburg, Germany DA - 30.01.2019 KW - Deckschichten KW - Korrosionsschutz KW - Passivität KW - Überzüge PY - 2019 AN - OPUS4-47325 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Babutzka, Martin T1 - Normentwurf für ein Prüfverfahren zur Bestimmung von Deckschichtwiderständen an Zinküberzügen mittels gelartiger Elektrolyte N2 - Der Vortrag stellt das WIPANO-Vorhaben GELELEK vor. Zu Beginn werden die Messtechnik und die Projektidee kurz erläutert. Anschließend wird ein Überblick über die Projektpartner, Projektziele und Arbeitsschritte gegeben. T2 - 66. Sitzung des NA 062-01-76 AA "Chemische und elektrochemische Überzüge" CY - Berlin, Germany DA - 19.03.2019 KW - Deckschichtbildung KW - Gelartige Elektrolyte KW - Korrosion KW - Zinküberzüge PY - 2019 AN - OPUS4-47575 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Babutzka, Martin T1 - Normentwurf für ein Prüfverfahren zur Bestimmung von Deckschichtwiderständen an Zinküberzügen mittels gelartiger Elektrolyte N2 - Der Vortrag stellt das WIPANO-Vorhaben GELELEK vor. Zu Beginn werden die Messtechnik und die Projektidee kurz erläutert. Anschließend wird ein Überblick über die Projektpartner, Projektziele und Arbeitsschritte gegeben. T2 - 12. Sitzung des NA 062-01-77 AA "Korrosionsprüfverfahren" CY - Berlin, Germany DA - 20.02.2019 KW - Korrosion KW - Zinküberzüge KW - Gelartige Elektrolyte KW - Deckschichtbildung PY - 2019 AN - OPUS4-47416 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Aristia, Gabriela T1 - The Effect of Different Polyaniline Types in Silicon Dioxide Containing Coatings for Carbon Steel Protection in Artificial Geothermal Brines N2 - According to the results of the experiments carried out, the following points can be concluded: 1. Exposure tests showed that specimens with the addition of SiO2 particles and polyaniline particles exhibit better corrosion resistance than specimens with the addition of only polyaniline particles or binder only. 2. Open circuit potential measurements showed that in the beginning of the experiments, both coatings had an open circuit potential 100 mV higher than carbon steel. Within one day of immersion, the potential of carbon steel increased significantly, indicating the formation of oxide layer. After extended exposure the carbon steel potential sat between PS1 (which had higher potential) and PS2 (which had a lower potential) and all three were in the range –600 mV to –500 mV vs Ag/AgCl. 3. Both coatings PS-1 and PS-2 were degraded with increasing exposure time, shown by the decrease of absolute impedance value at low frequency range after 2, 4, and 6 days exposure. 4. Potentiodynamic test was performed after 3 hours and 6 days exposure, and it was shown that the coating in the initial stage exhibited more passive behavior than the specimens exposed for 6 days. T2 - NACE International Corrosion Conference 2019 CY - Nashville, TN, USA DA - 24.03.2019 KW - Geothermal KW - Coating KW - Polyaniline KW - Corrosion PY - 2019 AN - OPUS4-47914 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bäßler, Ralph T1 - Material qualification in saline, copper containing geothermal water N2 - By exposure and electrochemical tests in the laboratory the Cu-effect on corrosion behavior of carbon steel, high-alloyed steels and Ti-alloy can be assessed. Critical materials specific properties were determined by static exposure and electrochemical tests in an artificial geothermal water with high salinity and low pH, containing Cu. Conclusions were drawn using characteristic potential values. It could be shown that significant Cu-deposition and -precipitation only occurred in combination with carbon steel. High-alloyed materials (S31603, S31653, S31700, S31703, S31803 and N08904) prevent the disturbing Cu-agglomeration. Therefore, they are suitable to be chosen for future design of the piping system, either in massive or in cladded form, if formation of crevices with non-metallic materials can be excluded. From the interactions and pitting corrosion point of view, R50400 seems to be most favorable. T2 - NACE International Corrosion Conference 2019 CY - Nashville, TN, USA DA - 24.03.2019 KW - copper KW - corrosion KW - geothermal energy KW - steel PY - 2019 AN - OPUS4-47912 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bäßler, Ralph T1 - Factors Influencing Droplet Corrosion in Dense Phase CO2 N2 - This work examined the factors that influence the droplet corrosion of CO2 pipeline steels caused by oxyfuel flue gases in dense phase CO2 at 278 K, simulating the underground transport conditions. The wetting properties were studied by contact angle measurement, revealing pH and time dependency on the reactive wetting behaviors of carbon steel X70. Exposure tests with CO2 saturated water droplet on steel surface showed that the impurities (220 ppmv SO2 and 6700 ppmv O2) diffused into the droplet and then reacted with metal surfaces in dense phase condition, forming the corrosion products. The corrosion rate was confirmed strongly depending on the droplet volume as well as the SO2 concentration. Condensation experiments carried out on freshly polished coupons in CO2 with 200 ppmv H2O, 220 ppmv SO2 and 6700 ppmv O2, showed that the formation and aggregation of droplets is time and temperature dependent. At 278 K, condensation happened stronger and the corrosion products, mainly consisted of dense hydrated FeSO3/FeSO4. While at 288 K, more fluffy corrosion products consisting of iron oxide/hydroxide and hydrated FeSO3/FeSO4 were found. Further exposure tests on carbon steel coupons with different surface roughness did not reveal the difference in weight loss/gain and therefore the corrosion rate. T2 - NACE International Corrosion Conference 2019 CY - Nashville, TN, USA DA - 24.03.2019 KW - Carbon Capture, Utilization and Storage (CCUS) KW - Supercritical/dense phase CO2 KW - Carbon steel KW - Droplet corrosion KW - Condensation PY - 2019 AN - OPUS4-47916 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Aristia, Gabriela T1 - Electrochemical measurement of polyaniline containing coating at high temperature: PROBLEMS AND CHALLENGES N2 - This presentation describes special aspects when performing measurements at high temperatures. Especially electrochemical issues are addressed for impedance spectroscopy, like overlapping time constants, handling of noise etc. T2 - Electrochemical Doctoral School “Corrosion: from analysis to modelling” CY - Brussels Belgium DA - 04.02.2019 KW - Polyaniline KW - Geothermal KW - Electrochemical impedance spectroscopy PY - 2019 AN - OPUS4-47917 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Burkert, Andreas T1 - Möglichkeiten und Grenzen elektrochemischer Messungen N2 - Elektrochemische Messungen sind für eine moderne Korrosionsforschung und –prüfung unverzichtbar. Aus dem Verständnis der Grundlagen können durch gezielte Modifizierung der Versuchsbedingungen unterschiedliche Fragestellungen beantwortet werden, wodurch bestehende Grenzen der Anwendung immer wieder verschoben werden können. Außerhalb etablierter Anwendungen stellen Auswahl und Einsatz geeigneter Verfahren sowie die Interpretation der Ergebnisse eine anspruchsvolle Aufgabe dar, die zwingend eine ausgewiesenen Fachexpertise voraussetzen. T2 - fkks infotag 2019 - Messen – Prüfen – Bewerten CY - Esslingen, Germany DA - 17.01.2019 KW - Korrosion KW - Elektrochemie KW - Gelelektrolyte PY - 2019 AN - OPUS4-47533 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Stelzner, Ludwig A1 - Weise, Frank A1 - Oesch, Tyler A1 - Dlugosch, R. A1 - Powierza, Bartosz T1 - Transport and reconfiguration of moisture in HPC due to unilateral heating N2 - Explosive spalling is caused by, among others, the thermohydraulic spalling mechanism. During this process, vaporization, dehydration, moisture-transport and condensation processes interact. As a result, a drying and dehydration zone as well as a saturated zone, known as a moisture clog, are observed inside the unilaterally-heated concrete. The presented research is focused on the experimental investigation of the underlying thermohydraulic processes. To investigate these, a test methodology based on X-ray computed tomography (CT) and nuclear magnetic resonance (NMR) was developed. Thereby, the X-ray CT scans are carried out simultaneously during the application of a defined unilateral-heating regime on a specially-constructed specimen. This miniaturized specimen, equipped with a double-layer casing, reproduces the condition within a planar, unilaterally-heated building component. A preliminary test methodology and the first experimental results were presented at the 5th International Workshop on Concrete Spalling in Borås, Sweden (2017). The contribution for the upcoming workshop presents an improved version of this test methodology and new results for a high-performance concrete (HPC) mixture exposed to temperatures up to 500 °C. Regarding the CT measurements, a higher time-resolution of 15 min was achieved and a quantification of the moisture changes was implemented. Due to an increase in signal quality of the NMR measurements, a pore-size specific moisture distribution can now be resolved. This allows to conclude about the moisture reconfiguration between small gel pores and larger interhydrate pores. Additionally, the NMR measurement are no longer limited to first 2.5 cm below the heated surface but a one-dimensional moisture distribution can now be estimated over the whole 10 cm long specimen. The presented results demonstrate that the combination of X-ray CT and NMR measurements enables to image and quantify the thermally-induced moisture transport and reconfiguration from small gel pores up to macro pores. This provides important insights into the thermohydraulic damage mechanism and leads to a better understanding of spalling avoidance strategies, like the addition of polypropylene fibres. T2 - 6th International Workshop on Concrete Spalling due to fire exposure CY - Sheffield, UK DA - 19.09.2019 KW - Moisture clog KW - X-ray CT KW - NMR KW - Moisture transport KW - HPC PY - 2019 UR - https://firespallingworkshop2019.group.shef.ac.uk/wp-content/uploads/2019/09/Fire-Spalling-Workshop_Proceedings.pdf SN - 978-1-5272-4135-0 SP - 181 EP - 190 CY - Sheffield AN - OPUS4-49161 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kratzig, A. A1 - Le, Quynh Hoa A1 - Bettge, Dirk A1 - Menneken, M. A1 - Bäßler, Ralph T1 - Early Stage of Corrosion Formation on Pipeline Steel X70 Under Oxyfuel Atmosphere at Low Temperature N2 - The early stage of corrosion formation on X70 pipeline steel under oxyfuel atmosphere was investigated by applying a simulated gas mixture (CO2 containing 6700 ppmv O2, 100 ppmv NO2, 70 ppmv SO2 and 50 ppmv H2O) for 15 h at 278 K and ambient pressure. Short-term tests (6 h) revealed that the corrosion starts as local spots related to grinding marks progressing by time and moisture until a closed layer was formed. Acid droplets (pH 1.5), generated in the gas atmosphere, containing a mixture of H2SO4 and HNO3, were identified as corrosion starters. After 15 h of exposure, corrosion products were mainly X-ray amorphous and only partially crystalline. In-situ energy-dispersive X-ray diffraction (EDXRD) results showed that the crystalline fractions consist primarily of water-bearing iron sulfates. Applying Raman spectroscopy, water-bearing iron nitrates were detected as subordinated phases. Supplementary long-term tests exhibited a significant increase in the crystalline fraction and formation of additional water-bearing iron sulfates. All phases of the corrosion layer were intergrown in a nanocrystalline network. In addition, numerous globular structures have been detected above the corrosion layer, which were identified as hydrated iron sulphate and hematite. As a type of corrosion, shallow pit formation was identified, and the corrosion rate was about 0.1 mma−1. In addition to in-situ EDXRD, SEM/EDS, TEM, Raman spectroscopy and interferometry were used to chemically and microstructurally analyze the corrosion products. KW - Corrosion KW - CCUS KW - In-situ ED-XRD KW - CO2 pipeline transport KW - Oxyfuel KW - Carbon steel KW - Impurities PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-506303 DO - https://doi.org/10.3390/pr8040421 SN - 2227-9717 VL - 8 IS - 4 SP - 421-1 EP - 421-19 PB - MDPI CY - Basel AN - OPUS4-50630 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schartel, Bernhard T1 - Small but Great – Multifunctional Graphene in Rubber Nanocomposites N2 - A few layer/multilayer graphene (MLG) with a specific surface area of BET ≥ 250 m2/g is proposed as an efficient multifunctional nanofiller for rubbers. The preparation method, i.e., ultrasonically-assisted solution or latex premixing of master batches followed by conventional two-roll milling, strongly influences the dispersion in the elastomeric matrix and is fundamental for the final properties. When homogenously dispersed, single stacks of only approximately 10 graphene sheets, with an aspect ratio of ca. 35, work at low loadings, enabling the replacement of large amounts of carbon black (CB), an increase in efficiency, and a reduction in filler load. The appropriate preparation yielded nanocomposites in which just 3 phr are sufficient to significantly improve the rheological, curing, gas barrier properties, electrical and thermal conductivity, as well as mechanical properties of different rubbers, as shown for chlorine-Isobutylene-Isoprene rubber (CIIR), nitrile-butadiene rubber (NBR), natural rubber (NR), and styrene-butadiene rubber (SBR).[1-5] 3 phr of MLG tripled the Young’s modulus of CIIR, an effect equivalent to 20 phr of CB. The stronger interactions between MLG and NR or SBR also resulted in a reduction in the elongation at break by 20% and 50%, respectively, while the same parameter was hardly changed for CIIR/MLG and NBR/MLG. CIIR/MLG and NBR/MLG were stiffer but just as defomable than CIIR and NBR. The strong reinforcing effect of 3 phr MLG was confirmed by the increase of greater than 10 Shore A in hardness. MLG reduces gas permeability, increases thermal and electrical conductivities, and retards flammability. We investigated MLG also as a synergist for reducing the aluminium trihydrate loading in flame retardant hydrogenated acrylonitrile-butadiene (HNBR), polybutadiene chloroprene (BR/CR), and chlorosulfonated polyethylene rubber(CSM).[6-8] The higher the nanofiller concentration is, the greater the improvement in the properties. For instance, the permeability decreased by 30% at 3 phr of MLG, 50% at 5 phr and 60% at 10 phr, respectively. Moreover, the MLG nanocomposites improve stability of mechanical properties against the effects of weathering. In key experiments an increase in UV-absorption and a pronounced radical scavenging were proved as stabilizing mechanisms. In a nutshell, MLG is an efficient multifunctional nanofiller ready to be used for innovative rubber development. T2 - 34th PDDG Conference CY - Dubrovnik, Croatia DA - 11.06.2023 KW - Graphene KW - Nanocomposites KW - Reinforcement KW - Antioxydant KW - Flame retardant KW - Durability PY - 2023 AN - OPUS4-57693 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Erning, Johann Wilhelm T1 - Susceptibility of 304 stainless steel to crevice corrosion in electrochemically active fluids N2 - The susceptibility of AISI 304 stainless steel to crevice corrosion on the effect of contact with electrochemically active fluids was investigated using exposure and stepwise potentiostatic polarisation. Crevice materials made up of 304 SS and Polyether ether ketone (PEEK) forming two kinds of crevices including 304 SS-to-PEEK and 304 SS-to-304 SS were tested. T2 - Eurocorr 2019 CY - Sevilla, Spain DA - 09.09.2019 KW - ECA KW - Crevice KW - Corrosion KW - Stainless KW - Steel PY - 2019 AN - OPUS4-49282 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Erning, Johann Wilhelm T1 - Susceptibility of 304 stainless steel to crevice corrosion in electrochemically active fluids N2 - The crevice corrosion behaviour of stainless steel 304 L n ECA fluids is investigated. Results are described, rules for operation are suggested T2 - Ceocor-Tagung 2019 CY - Copenhagen, Denmark DA - 21.05.2019 KW - Desinfection KW - Crevice corrosion KW - ECA PY - 2019 AN - OPUS4-49280 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Klein, Ulrich T1 - Messing unter Druck N2 - Schäden an verschiedenen Rohrverbindungs-Systemen im Sanitärbereich mit Bauteilen aus Messing. T2 - GfKORR Arbeitskreis Schadensanalyse CY - Frankfurt a.M., Germany DA - 17.10.2019 KW - Pressverbindung KW - Spannungsrisskorrosion KW - Messing KW - Schadensanalyse PY - 2019 AN - OPUS4-49335 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Erning, Johann Wilhelm T1 - Observations of copper pitting corrosion in german tap waters N2 - In recent years, a new type of pitting corrosion is observed on half-had copper pipes. examples are given and possible reasons are discussed T2 - Eurocorr 2019 CY - Sevilla, Spain DA - 09.09.2019 KW - Water KW - Pitting KW - Corrosion KW - Copper KW - Drinking PY - 2019 AN - OPUS4-49281 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Erning, Johann Wilhelm T1 - A new type of copper pitting corrosion in german tap waters N2 - Half-hard copper pipes show pitting corosion under conditions until now seen as uncritical. Examples are discussed, possible causes described. T2 - MTECH 2019 CY - Porec, Croatia DA - 09.10.2019 KW - Drinking KW - Pitting KW - Corrosion KW - Copper KW - Water PY - 2019 AN - OPUS4-49283 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Stelzner, Ludwig T1 - Transport and reconfiguration of moisture in HPC due to unilateral heating N2 - Explosive spalling is caused by, among others, the thermohydraulic spalling mechanism. During this process, vaporization, dehydration, moisture-transport and condensation processes interact. As a result, a drying and dehydration zone as well as a saturated zone, known as a moisture clog, are observed inside the unilaterally-heated concrete. The presented research is focused on the experimental investigation of the underlying thermohydraulic processes. To investigate these, a test methodology based on X-ray computed tomography (CT) and nuclear magnetic resonance (NMR) was developed. Thereby, the X-ray CT scans are carried out simultaneously during the application of a defined unilateral-heating regime on a specially-constructed specimen. This miniaturized specimen, equipped with a double-layer casing, reproduces the condition within a planar, unilaterally-heated building component. A preliminary test methodology and the first experimental results were presented at the 5th International Workshop on Concrete Spalling in Borås, Sweden (2017). The contribution for the upcoming workshop presents an improved version of this test methodology and new results for a high-performance concrete (HPC) mixture exposed to temperatures up to 500 °C. Regarding the CT measurements, a higher time-resolution of 15 min was achieved and a quantification of the moisture changes was implemented. Due to an increase in signal quality of the NMR measurements, a pore-size specific moisture distribution can now be resolved. This allows to conclude about the moisture reconfiguration between small gel pores and larger interhydrate pores. Additionally, the NMR measurement are no longer limited to first 2.5 cm below the heated surface but a one-dimensional moisture distribution can now be estimated over the whole 10 cm long specimen. The presented results demonstrate that the combination of X-ray CT and NMR measurements enables to image and quantify the thermally-induced moisture transport and reconfiguration from small gel pores up to macro pores. This provides important insights into the thermohydraulic damage mechanism and leads to a better understanding of spalling avoidance strategies, like the addition of polypropylene fibres. T2 - 6th International Workshop on Concrete Spalling due to fire exposure CY - Sheffield, UK DA - 19.09.2019 KW - Moisture clog KW - X-ray CT KW - NMR KW - Moisture transport KW - HPC PY - 2019 AN - OPUS4-49159 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Langklotz, U. T1 - FT-IR spectroscopy of corrosion products formed on zinc under atmospheric conditions N2 - Zinc materials are of high importance in the field of corrosion protection. For example, almost half of the annual production of zinc is used as anti-corrosive layer for steel components, particularly under atmospheric conditions. The corrosion protection is frequently ascribed to zinc carbonate species with low solubility which form on the metal surface under atmospheric conditions. Due to the technological importance and wide use of zinc materials, its corrosion behavior and the formation of reaction products has been intensively investigated over decades. Assuming atmospheric corrosion conditions, an initial native passive film of few nanometers thickness forms spontaneously. It consists of zinc oxide and hydroxide, transforming into various species in dependence of the surrounding atmospheric conditions. This study focusses on the investigation of corrosion product layers on massive titanium-zinc sheets, formed during short- and mid-term exposure experiments by Fourier-transformed infrared spectroscopy. This method enables the investigation of extremely thin native passive films which form during the initial hours of exposure. Furthermore, aged surface layers are analyzed which were formed by transformation of initial passive layers over the time of several weeks. The spectroscopic investigations are complemented by scanning electron microscopy (SEM/EDX) in order to obtain information on the chemical composition and morphology of the corrosion products. The combination of both methods offers a comprehensive view on the processes occurring in the early stages of zinc corrosion. T2 - EUROCORR 2019 CY - Sevilla, Spain DA - 09.09.2019 KW - Zinc coatings KW - FT-IR KW - Layer formation PY - 2019 AN - OPUS4-49132 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Babutzka, Martin T1 - Neue Erkenntnisse zur Deckschichtbildung von Zink an der Atmosphäre N2 - Die Untersuchungen und Ausführungen im Vortrag belegen, dass verfügbare Modellvorstellungen zur Beschreibung der Deckschichtbildung und Korrosion von Zink unter aktuellen atmosphärischen Bedingungen in Europa nicht mehr gültig sind und neu bewertet werden müssen. So können beispielsweise bisher verfügbare Prognosemodelle den Korrosionsfortschritt nicht mehr ausreichend beschreiben, da durch die Verringerung des Schwefeldioxidgehaltes der Luft veränderte Mechanismen vorliegen. T2 - Sitzung des GfKORR Arbeitskreises „Zink und Zinküberzügel“ CY - Online meeting DA - 28.09.2021 KW - Atmosphärische Korrosion KW - Deckschichtbildung KW - Gelartige Elektrolyte KW - Zink PY - 2021 AN - OPUS4-53410 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schartel, Bernhard T1 - Weathering resistance of halogen-free flame retardancy in thermoplastics N2 - Weathering resistance of halogen-free flame retardancy in thermoplastics - Durability of fire retardancy - Impact of different exposure condition - Degradation with respect to different fire tests T2 - 17th SKZ Conference on Trends in Fire Safety and Innovative Flame Retardants for Plastics CY - Online Meeting DA - 18.05.2021 KW - Durability KW - Flame retardant KW - Aluminum hydroxide (ATH) KW - Weathering KW - Cable KW - TPU KW - EVA KW - Polyamide 6.6 KW - Aluminium diethylphosphinate PY - 2021 AN - OPUS4-52680 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rütters, R. T1 - Towards defining reasonable minimum composition thresholds – impacts of variable CO2 stream compositions on transport, injection and storage N2 - The collaborative project “Impacts of impurities in CO2 streams captured from different emitters in a regional cluster on transport, injection and storage (CLUSTER)” aimed to set up recommendations on how to define “reasonable minimum composition thresholds” that CO2 streams should meet when accessing CO2 transport pipeline networks. Within CLUSTER, we investigated potential impacts of CO2 streams with different and temporally variable compositions and mass flow rates along the whole CCS chain. Investigations included, amongst others, impacts on: Corrosion of pipeline steel, pipeline network design and related transport costs, alteration of well bore cements, pressure evelopment and rock integrity, geochemical reactions, and petrophysical and geomechanical rock properties. All investigations are based on a generic CCS chain scenario. In this scenario, CO2 streams are captured from a spatial cluster of eleven emitters and collected in a regional pipeline network. Emitters comprise seven fossil fuel-fired power plants equipped with different capture technologies, two cement plants, one refinery and one integrated iron and steel plant. In total, 19.78 Mio t CO2 (including impurities) are captured in the emitter cluster annually. The combined CO2 stream is transported in a trunk line with a length of 400 km (100 km of these offshore) and is injected into five generic storage structures. The storage reservoirs are saline aquifers of the Buntsandstein. The investigations revealed beneficial and deteriorating impacts of different impurities and combinations thereof. Overall, no fundamental technical obstacles for transporting, injecting and storing CO2 streams of the modelled variable compositions and mass flow rates were observed. Based on the results, the CLUSTER project team recommends not to define “minimum composition thresholds” for CO2 streams as strict threshold values for eachindividual impurity in the stream. Instead, CO2 stream compositions and variabilities for specific CCS projects should be constrained with regard to a set of parameters including i) the overall CO2 content, ii) maximum contents of relevant impurities or elements, iii) acceptable variability of CO2 stream composition, and iv)impurity combinations to be avoided. T2 - 15th International Conference on Greenhouse Gas Control Technologies, GHGT-15 CY - Online meeting DA - 15.03.2021 KW - Corrosion KW - Impurities KW - CO2 quality KW - Pipeline network KW - Whole-chain CCS scenario KW - Recommendations PY - 2021 AN - OPUS4-52419 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Tian, H. T1 - Composition and microstructure stability of cement compound under cyclic hydrothermal condition N2 - There have been many researches focused on the performance improvement of ultra-high performance concrete (UHPC) by autoclaving treatment. The goal of autoclaving is to increase the pozzolanic reaction, and to densify the cement stone and the transition zone which originates from the incorporation of supplementary cementitious materials (SCMs), such as silica fume, fly ash and blast furnace slag. Due to the superior properties, UHPC can also be utilized under high mechanical load and aggressive condition, for example, the fabrication of water tanks for thermal storage which is of great significance for saving energy and reducing CO2 emission. It is known that mineral stability of the hydration products of an inorganic binder is highly related to the temperature and pressure of the environment. A certain stable composition at room temperature, however, may undergo a phase transformation at high temperature and the performance decrease under this severe condition will generally be more severe. In this way, the rationale behind this deterioration under long-term hydrothermal condition involving many cycles and long duration has to be clarified, and then appropriate optimizing methods will be performed in order to obtain a kind of construction with high durability under aggressive environment. For this purpose, different types and amounts of SCMs are introduced into the standard mixture of UHPC and the phase compositions after autoclaving at 200 °C and 15.5 bar are determined by combined X-ray diffraction and scanning electron microscope. Mercury intrusion porosimeter is used to characterise the microstructure of the samples. In order to establish the relationship between microstructure and macroscopic properties, compressive and flexural strength are also investigated. T2 - HiPerMat 2020 CY - Kassel, Germany DA - 11.03.2020 KW - Hydrothermal treatment KW - UHPC KW - Composition PY - 2020 AN - OPUS4-52377 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Babutzka, Martin T1 - Prozess- und materialbedingte Ursachen für Korrosionserscheinungen an nichtrostenden Stählen N2 - Der Vortrag beleuchtet prozess- und materialbedingte Ursachen für Korrosionserscheinungen an nichtrostenden Stählen. Der Fokus liegt auf dem Einfluss von Schleifprozessen. Es werden Maßnahmen erläutert, um die Korrosionsbeständigkeit der Oberfläche zu verbessern. T2 - 3M Webinar „Schleiftechnologien zur Korrosionsvermeidung und Produktivitätssteigerung“ CY - Online meeting DA - 25.03.2021 KW - Nichtrostender Stahl KW - Korrosion KW - Schleifprozesse PY - 2021 AN - OPUS4-52360 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Babutzka, Martin T1 - Process- and material-related causes for corrosion defects on stainless steels N2 - The presentation provides information on process- and material-related causes for corrosion on stainless steels. The influence of surface grinding is discussed. Methods for enhancing the corrosion resistance of stainless steels are shown. T2 - 3M Webinar “Technologies, Tools & Tips to avoid corrosion on Stainless Steel” CY - Online meeting DA - 25.02.2021 KW - Stainless steel KW - Corrosion KW - Grinding processes PY - 2021 AN - OPUS4-52358 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schilling, Markus T1 - Umgebungsinduzierte Spannungsrissbildung (ESC) von PE-HD induziert durch äußerliche Einwirkung organischer Flüssigkeiten N2 - Polyethylen hoher Dichte (PE-HD) wird als Werkstoff für Rohre und Behälter für den Transport und zur Lagerung von Gefahrgütern verwendet. Für die Beurteilung und technische Freigabe dieser Materialien ist insbesondere das Verständnis des Schädigungsmechanismus des langsamen, umgebungsbedingten Spannungsrisses (engl.: „environmental stress cracking“, ESC) essentiell. ESC tritt bei relativ geringen auf einen Werkstoff einwirkenden mechanischen Spannungen auf. An lokalen Fehlstellen (z.B. Defekte, Inhomogenitäten, Kerben) beginnend wächst ein Riss langsam durch das Material und führt nach gewisser Zeit zu einem charakteristischen, pseudo-spröden Bruch. Dabei wird das Risswachstum durch äußere Medieneinwirkung zusätzlich entscheidend beeinflusst. Dieses langsame Risswachstum wird als Hauptursache für das plötzliche und unerwartete Versagen von Polymerwerkstoffen angesehen. Eine etablierte Prüfmethode zur Bewertung des Materialverhaltens gegenüber dieses Schädigungsmechanismus ist der Full-Notch Creep Test (FNCT), der für PE-HD Behältermaterialien üblicherweise unter Verwendung von wässrigen Netzmittellösungen (Arkopal N 100) durchgeführt wird. Die aus dem FNCT erhaltene Standzeit dient dabei als Bewertungskriterium für verschiedene PE-HD-Werkstoffe. In einer Studie wurden neben einer typischen Arkopal-N-100-Netzmittellösung praktisch relevante, organische Flüssigkeiten wie Biodiesel und Diesel als Testmedien verwendet, um deren Einfluss auf das ESC-Verhalten von PE-HD-Behältermaterialien zu charakterisieren. Neben der klassischen Standzeit-Auswertung erfolgte eine erweiterte Bruchflächenanalyse mittels Licht- (LM), Laserscanning- (LSM) und Rasterelektronenmikroskopie (REM). Insbesondere die LSM erlaubt eine schnelle und einfache Unterscheidung pseudo-spröder und duktiler Bruchbilder, die zur Beurteilung der Repräsentativität des FNCT für das dem Spannungsriss zugrundeliegenden langsamen Risswachstum von Bedeutung ist. T2 - Polymer Service GmbH Merseburg - "Lebensdauerabschätzung von Polymerwerkstoffen - Möglichkeiten und Grenzen" CY - Merseburg, Germany DA - 27.03.2019 KW - Environmental Stress Cracking (ESC) KW - Slow Crack Growth (SCG) KW - Spannungsriss KW - Polyethylen hoher Dichte KW - Full-Notch Creep Test (FNCT) KW - Bruchflächenanalyse KW - Laserscanningmikroskopie (LSM) PY - 2019 AN - OPUS4-52947 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Seneschal-Merz, Karine T1 - New UV-protective glazing for the conservation of cultural assets N2 - For centuries, churches, secular buildings and museums have been furnished with valuable works of art. Many works of art are UV- and light-sensitive. It is well known that especially UV radiation causes damage and discoloration in paintings, textiles, plastics, wood and other materials. In particular, the wavelengths between 280 and 410 nm cause color changes, embrittlement or destruction of e.g. plastics over time. Therefore, strongly UV-absorbing glasses are advantageous for architecture and are necessary for the protection of cultural assets. As restorers in all disciplines become more and more aware, the demands placed on buildings and their furnishings in terms of climate are becoming increasingly detailed and precise. The aim in each case is to preserve the valuable artwork. For some years now, the industry has been offering the protection of cultural objects by installing special UV-protective glasses. Currently, UV protection for church buildings is realized by laminated safety glass equipped with appropriate UV-protective plastic films. Technically, this always means a second pane of glass in front of the windows, which is installed outside the building. This creates climatic gaps that are difficult to control and deterioration due to ageing effects can be expected. At the same time, this protective glazing is not invisible and has a considerable aesthetic influence on the interior and exterior appearance of the building. Meanwhile, the preservation of historical monuments accepts such aesthetic cuts on buildings in order to protect the artwork in the interior from UV light. To this day, however, the long-term durability of UV protection provided by inserted plastic films is still controversial. To date the only available alternative on the market is a mouth-blown UV protection glass which uses a so-called overlay to provide UV protection. This shows that UV protection can also be achieved by glasses without plastic films thus realizing an exclusive inorganic protection which normally is more stable than a polymeric one. So far there are not enough studies to prove long-term durability. The aim of this project is to provide existing glazing or new glazing to be created with a highly transparent layer that ensures this UV-protective filter function below 400 nm. The glass coating is to be applied to the glass over a large area and fired into the surface like a classic ceramic enamel paint with the same technics. In addition, it should be long-term durable in its function. It means, that the glass has to be fused at temperatures below 630 °C during the firing process, its chemical durability has to be high, its coefficient of thermal expansion has to be as close as the one of the substrate (usually float glass) and the glass has to absorb the UV-radiation within a thin thickness (thinner as 100 µm). In this project, the long-term durability of commercial UV-protective glasses is examined. New low melting glasses containing UV-absorbing ions are being developed. Their UV-absorption as a thin layer is analyzed as well as their chemical durability and their thermal properties. We are grateful to BMWI for the financial support in the frame of the Central Innovation Programme for SMEs (ZIM). T2 - HVG-DGG: 94. Glastechnische Tagung CY - Online meeting DA - 10.05.2021 KW - Glass KW - Low melting KW - Chemical durability KW - Weathering tests KW - Aging test KW - UV absorption KW - UV protection KW - Architecture KW - Optical properties PY - 2021 AN - OPUS4-52648 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Wagner, Adrian T1 - Vorstellung und Diskussion der Ergebnisse der 1. Probenentnahme. Im Rahmen des Forschungsprojektes zur Auslagerung von Edel- und Duplexstählen in Straßentunneln N2 - Ziel des Projektes ist die Qualifizierung von Duplexstählen in Tunnelbauwerken um die Einsatzmöglichkeiten alternativer nichtrostender Stähle zu den bislang gebräuchlichen rostfreien Edelstählen 1.4404 und 1.4571 zu eruieren. Da Duplexstähle im Vergleich zu austenitischen Stählen über eine doppelt so hohe Festigkeit verfügen, können Bauteile schlanker konstruiert werden, wodurch Material eingespart werden kann. Neben der Wirtschaftlichkeit muss die Dauerhaftigkeit untersucht werden. Dazu wurden speziell konzipierte Wand- und Deckenracks mit unterschiedlichen metallenen Werkstoffen und Oberflächen hergestellt und in den Tunnelbauwerken montiert. Nach bestimmten Auslagerungszeiten von bis zu drei Jahren werden die Proben demontiert und auf ihr Korrosionsverhalten untersucht. Ein weiteres Ziel neben der Qualifizierung der Werkstoffgruppe sind die Reduktion der Instandsetzungs- und Wartungsmaßnahmen der Tunnelbetreiber. T2 - Vorstellung und Diskussion der Ergebnisse der 1. Probenentnahme im Rahmen des Forschungsprojektes zur Auslagerung von Edel- und Duplexstählen in Straßentunneln CY - Dusseldorf, Germany DA - 19.06.2019 KW - Korrosion KW - Tunnel KW - Duplexstahl PY - 2019 AN - OPUS4-48330 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Metz, Christian T1 - Zerstörungsfreie Charakterisierung der Alterung additiv gefertigter Kunststoffbauteile N2 - Es wurden mittels Fused Layer Modeling (FLM) Probekörper aus ABS und mittels Laser Sintering (LS) Probekörper aus PA 12 hergestellt, die anschließend für drei Monate einer künstlichen Bewitterung unterzogen wurden. Die dabei erzeugte definierte Alterung wurde nach drei Zeitabschnitten jeweils mit zerstörungsfreien Methoden charakterisiert. Dabei wurde neben den spektroskopischen Standardmethoden auch die aktive Thermografie eingesetzt. Die Ergebnisse zeigen, dass sich mittels der Thermografie sowohl chemische Veränderungen als auch mechanische Schädigungen (Fehlstellen) darstellen lassen. Die Bewitterung beeinflusst die Teiltransparenz der Proben zumindest im sichtbaren Spektralbereich, was bei der Charakterisierung der Fehlstellen, die mittels optisch angeregter aktiver Thermografie detektiert wurden, berücksichtigt werden muss. Die Erkenntnisse dienen für die Entwicklung einer Strategie für eine Qualitätskontrolle von additiv gefertigten Kunststoffteilen. T2 - DACH-Jahrestagung 2019 - Zerstörungsfreie Materialprüfung CY - Friedrichshafen, Germany DA - 27.05.2019 KW - Additive Fertigung KW - Künstliche Bewitterung KW - Thermografie KW - Zerstörungsfreie Prüfung KW - additive manufacturing KW - Kunststoffe PY - 2019 AN - OPUS4-48331 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Le, Quynh Hoa A1 - Bäßler, Ralph A1 - Bettge, Dirk A1 - Buggisch, E. A1 - Schiller, Bernadette Nicole A1 - Beck, M. T1 - Corrosion Study on Wellbore Materials for the CO2 Injection Process N2 - For reliability and safety issues of injection wells, corrosion resistance of materials used needs to be determined. Herein, representative low-cost materials, including carbon steel X70/1.8977 and low alloyed steel 1.7225, were embedded in mortar to mimic the realistic casing-mortar interface. Two types of cement were investigated: (1) Dyckerhoff Variodur commercial Portland cement, representing a highly acidic resistant cement and (2) Wollastonite, which can react with CO2 and become stable under a CO2 stream due to the carbonation process. Exposure tests were performed under 10 MPa and at 333 K in artificial aquifer fluid for up to 20 weeks, revealing crevice corrosion and uniform corrosion instead of expected pitting corrosion. To clarify the role of cement, simulated pore water was made by dispersing cement powder in aquifer fluid and used as a solution to expose steels. Surface analysis, accompanied by element mapping on exposed specimens and their crosssections, was carried out to trace the chloride intrusion and corrosion process that followed. KW - Carbon capture storage KW - CCS KW - Carbon dioxide KW - Corrosion KW - Carbon steel KW - Aquifer fluid KW - Cement KW - Casing KW - Pitting PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-519774 DO - https://doi.org/10.3390/pr9010115 SN - 2227-9717 VL - 9 IS - 1 SP - 115 PB - MDPI CY - Basel AN - OPUS4-51977 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schartel, Bernhard T1 - Sustainability Finding its Way into Flame Retardancy: Food for Thought between Fake Fiction and Future N2 - Main message: Sustainability, or in other words, exploiting environmental conservation for the economic welfare and prosperity for all, would revolutionise the plastics industry were it to become predominant practice as a linear, fossil-fuel–based economy is switched to a carbon circular economy. Food for though is given by dint of a critical overview of the current trends in sustainable flame-retardant polymeric materials. Introduction: Transforming the plastics industry into a carbon circular economy over the next 30 years requires an immediate revolution entailing the development of cutting-edge materials and the planning of future industrial production plants. Hence, the innovative field of flame-retardant polymeric materials should lend its strength to drive this challenge. Visionary solutions are proposed to inspire us, while the implementation of economically feasible concepts can take us forward into the future. Experimental The synthesis, processing, polymer analysis, thermal analysis, and investigation of fire behaviour from our own research are performed according to the state of the art, mostly in accordance with the pertinent ISO standards. Indeed, some of our equipment is part of the accredited lab; for the other methods we fulfil equivalent quality standards in terms of maintenance, calibration, participation in round robins, etc. Work steps such as the synthesis or preparation of new materials are usually outsourced or done with partners that have the relevant core competence. The talk also presents examples from other groups whose experimental is described in the corresponding scientific papers. Results and Discussion An overview of current trends towards producing sustainable, flame-retardant polymeric materials is presented, using examples from the literature and by sketching our own projects performed in recent years. The examples are structured along a common theme leading from the use of old and new natural materials with some intrinsic flame retardancy, via flame-retardant biopolymers and biocomposites, to using renewable sources for flame retardants with the objective of exploiting natural sources available as industrial waste streams. Natural flame retardants and adjuvants are highlighted, although the status of most may be assessed as merely motivating our vision. Nevertheless, there are natural material streams finding their way into polymer mass production as fillers, adjuvants, polymers, or renewable educt sources. Natural substances originating from industrial waste streams open the door to sustainable solutions, because they are often available at low cost and avoid competition for land with farming or virgin forests. Aside from this main topic, remarks will address the recycling of flame-retarded polymeric materials; vitrimers are mentioned as a potential material for recyclable thermosets. At the end of the day, only convincing property profiles will prevail both for exploiting renewable sources and circular design, including cost effectiveness, sufficient availability, consistent quality, processibility, mechanical properties, and flame retardancy. However, sustainability must not be merely tolerated as an additional demand, but should instead be recognized as a solution, because sustainability aspires to ensure our economic welfare now and in the future. Acknowledgement: The examples shown from own project were supported by funding grants: BMBF WTZ: 01DN16040, DFG Scha 730/19-1, VW-Stiftung: Experiment No: 97437, DFG Scha 730/20-1, BMBF KMU Innovativ 031B1289B. T2 - 19th European Meeting on Fire Retardant Polymeric Materials (FRPM23) CY - Dübendorf, Switzerland DA - 26.06.2023 KW - Renewable KW - Biocomposite KW - Sustainable KW - Circular economy KW - Natural PY - 2023 AN - OPUS4-57815 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rosemann, P. T1 - Ursachen korrosionsanfälliger Oberflächen bei geschliffenen nichtrostenden Stählen N2 - Ergebnisse aus dem AiF Forschungsvorhaben IGF 18823 N/1 "Optimierung von Korundschleifprozessen" Ein Referenzwerkstoff mit einem definierten Oberflächenzustand wurde zunächst umfassend mittels elektrochemischer Korrosionsuntersuchungen, KorroPad-Untersuchungen und oberflächenanalytischer Verfahren charakterisiert. Anhand definierter Schleifversuche an diesem Referenzzustand wurden anschließend verschiedene Schleifparameter variiert, deren Auswirkungen auf die Korrosionsbeständigkeit mit den gleichen Methoden beurteilt wurden. Somit war es möglich, den Einfluss einzelner Schleifparameter auf das Korrosionsverhalten aufzuzeigen. T2 - MDZ Forschungsseminar 2019 CY - Magdeburg, Germany DA - 12.03.2019 KW - Nichtrostender Stahl KW - Korrosionsschnelltest KW - KorroPad KW - Passivschicht PY - 2019 AN - OPUS4-47535 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Bäßler, Ralph T1 - Review: Polymer Coatings ‐ A Guide to Chemistry, Characterization, and Selected Applications N2 - This book grew out of a course on polymer coatings held by the author at the university. It shall serve as an introduction to the wide field of polymer coatings. It is not intended to cover completely all facts on polymer coatings. All chapters are well structured. Selected figures and formulas illustrate the content and contribute to a good understandability. At the end of each chapter some hints for further reading are provided. Finally, the book fulfills its intention to introduce into the topic by providing basics on science and technology of polymer coatings, suitable for chemists in industry, materials scientists, polymer chemists and physical chemists. KW - Corrosion KW - Coating KW - Polymer PY - 2020 DO - https://doi.org/10.1002/maco.202070024 SN - 1521-4176 SN - 0947-5117 VL - 71 IS - 2 SP - 321 EP - 322 PB - WILEY‐VCH Verlag GmbH & Co. KGaA CY - Weinheim AN - OPUS4-50374 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Babutzka, Martin T1 - New findings on the formation of corrosion product layers on zinc in the atmosphere N2 - The presentation shows systematic investigations to describe the corrosion and corrosion product formation processes of pure zinc under the climatic conditions currently prevailing in the Federal Republic of Germany. The investigations in their entirety aim at questioning current and establishing new ways of looking at the formation of corrosion products of pure zinc under atmospheric corrosion conditions. Thus, they make a significant contribution in understanding corrosion protection by zinc and zinc coatings. In particular, the focus is placed on the initial stage of the corrosion product formation. A systematic investigation of this time range, which is characterized by very reactive corrosion products, is only made possible by using gel-type electrolytes. The short periods of time at the beginning of weathering is now measurable and their influence on the formation of corrosion products and the kinetics of layer formation describable. By combining the new electrochemical approach with gravimetric, microscopic and analytical methods, new insights could be gained both on a methodic and scientific level. T2 - 26th International Galvanizing Conference and Exhibition CY - Rome, Italy DA - 20.06.2022 KW - Atmospheric Corrosion KW - Corrosion KW - Corrosion products KW - Gel-type electrolytes KW - Zinc PY - 2022 AN - OPUS4-55113 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Babutzka, Martin T1 - Forschungsprojekt RUNOFF: "Neubewertung der Dauerhaftigkeit von Dach- und Fassadenmaterialien und des Eintrags von Schwermetall-Ionen in die Umwelt hervorgerufen durch Runoff„ N2 - Bei Betrachtungen zur Lebensdauer von Metallbauteilen im Bauwesen müssen Korrosions- und Runoff-Vorgänge an der Atmosphäre als verschiedene Reaktionen unterschieden werden. Korrosion ist der Prozess, der von elektrochemischen Reaktionen an der Grenzfläche Metall/Patina kontrolliert wird. Runoff dagegen wird durch chemische Reaktionen an der Grenzfläche Patina/Atmosphäre begünstigt. Mit zunehmender Bewitterungszeit nimmt die Korrosionsgeschwindigkeit stetig ab, während postuliert wird, dass die Geschwindigkeit des Runoffs über die gesamte Zeit konstant bleibt. Dieses Verhalten des Runoffs muss aber zunehmend bezweifelt werden. Die Gesamtmenge an abgezehrtem Metall beinhaltet zwei Bestandteile. Ein Teil wird in die Schicht aus Korrosionsprodukten eingebaut, der andere wird aufgrund von Niederschlägen aus der Patina gelöst. Aus diesem Grund ist die Menge an Zink-Runoff stark abhängig von den Eigenschaften der Korrosionsprodukt- bzw. Patinaschicht und nicht anhand der Zusammensetzung des Metalls abschätzbar. Vorhandene Modelle können die Menge an Runoff, und damit verbunden die Abzehrung einer Schicht aus Zink und Kupfer, sowie den resultierenden Eintrag von Schwermetallionen in die Umwelt nicht mehr darstellen und erklären. Um den Korrosionsschutz an Bauwerken zum einen dauerhaft unter Beachtung von Kostenaspekten und Ressourcenschonung und zum anderen unter ökologischen Gesichtspunkten auslegen zu können, müssen deshalb neue wissenschaftliche Grundlagen erarbeitet und die Mechanismen beschrieben werden. Das BAM-Forschungsvorhaben RUNOFF widmet sich den Fragestellungen. Der Vortrag gibt einen kurzen Überblick zum Forschungsvorhaben. T2 - 19. Projektetage der Bauforschung CY - Online meeting DA - 22.03.2022 KW - Runoff KW - Zink KW - Korrosion KW - Kupfer PY - 2022 AN - OPUS4-54580 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hille, Falk T1 - Developing a guideline for SHM of road bridges in Germany N2 - In recent years, Structural Health Monitoring (SHM) has become a useful and increasingly widely used tool for supporting lifetime extensions of existing bridges with known structural deficiencies or indications of potentially critical damages or damage processes. At the same time, methods and tools are emerging, which enable monitoring-informed predictive maintenance of new and existing bridges based on digital twins. The monitoring process – starting from the definition of monitoring actions and ending with decisions based on monitoring outcomes – is complex and requires expertise in structural engineering, operation and maintenance of bridges, metrology, and data analytics. To support German road authorities, engineering consultancies, building contractors and other stakeholders of the bridge management, the Federal Highway Research Institute (BASt) has initiated the development of a new guideline for applying SHM as part of the management of road bridges. The guideline will present various use cases and for each identified use case, it will propose a proven monitoring scheme. In addition, the guideline will provide guidance on assessing the benefits of SHM as well as a common approach to managing monitoring data as a systematic basis for integrating monitoring data in the bridge management. This contribution discusses the motivation, objectives, and scope of the guideline, describes its use case centric structure and outlines the proposed data management. T2 - IABMAS 2024 CY - Kopenhagen, Danmark DA - 24.06.2024 KW - Guideline KW - Infrastructure KW - Structural health monitoring KW - Road bridges PY - 2024 AN - OPUS4-61395 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Simon, Patrick A1 - Schneider, Ronald A1 - Baeßler, Matthias A1 - Morgenthal, Guido ED - Cha, Young-Jin T1 - A Bayesian Probabilistic Framework for Building Models for Structural Health Monitoring of Structures Subject to Environmental Variability N2 - Managing aging engineering structures requires damage identification, capacity reassessment, and prediction of remaining service life. Data from structural health monitoring (SHM) systems can be utilized to detect and characterize potential damage. However, environmental and operational variations impair the identification of damages from SHM data. Motivated by this, we introduce a Bayesian probabilistic framework for building models and identifying damage in monitored structures subject to environmental variability. The novelty of our work lies (a) in explicitly considering the effect of environmental influences and potential structural damages in the modeling to enable more accurate damage identification and (b) in proposing a methodological workflow for model‐based structural health monitoring that leverages model class selection for model building and damage identification. The framework is applied to a progressively damaged reinforced concrete beam subject to temperature variations in a climate chamber. Based on deflections and inclinations measured during diagnostic load tests of the undamaged structure, the most appropriate modeling approach for describing the temperature‐dependent behavior of the undamaged beam is identified. In the damaged state, damage is characterized based on the identified model parameters. The location and extent of the identified damage are consistent with the cracks observed in the laboratory. A numerical study with synthetic data is used to validate the parameter identification. The known true parameters lie within the 90% highest density intervals of the posterior distributions of the model parameters, suggesting that this approach is reliable for parameter identification. Our results indicate that the proposed framework can answer the question of damage identification under environmental variations. These findings show a way forward in integrating SHM data into the management of infrastructures. KW - Verkehrsinfrastukturen KW - SHM KW - Model Updating KW - Environmental and Operational Variability KW - Damage Identification KW - Model Building PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-605027 DO - https://doi.org/10.1155/2024/4204316 SN - 1545-2255 VL - 2024 IS - 1 SP - 1 EP - 23 PB - Wiley AN - OPUS4-60502 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Baeßler, Matthias A1 - Simon, Patrick T1 - Ballasted track on vibrating bridge decks: physical mechanisms, empirical findings, and a proposal for assessment N2 - This paper summarizes the key findings and physical mechanisms and provides information on open questions and the assessment of railway bridge superstructure vibrations. Bridges are classic disruption points on a railway track. If bridge superstructures are dynamically excited by train traffic, the vertical accelerations of the track must be considered. For a ballasted track, this can lead to the destabilization of the ballast track, as the bridge superstructure acts like a vibrating table. In this respect, the paper explains in more detail what is meant by destabilization, when this destabilization occurs and how various influencing parameters such as acceleration amplitude, the vibration sequence and frequency affect its occurrence. In the InBridge4EU project, gaps in knowledge such as the effect of single impulse loads are being investigated experimentally. A new test facility has been set up for this purpose, the initial results of which are presented here. An essential element in the assessment of this scenario is the stability of the track under high compression forces with simultaneous dynamic excitation of the superstructure. A new approach for the assessment of bridge vibrations with respect to lateral stability is presented. KW - Railway bridge dynamics KW - Bridge deck acceleration KW - Ballast destabilization KW - Lateral track stability KW - Track buckling PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-630972 DO - https://doi.org/10.1142/S0219455425400243 SN - 0219-4554 SN - 1793-6764 IS - 2540024 SP - 1 EP - 27 PB - World Scientific CY - Singapore AN - OPUS4-63097 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Herrmann, Ralf A1 - Ramasetti, Eshwar Kumar A1 - Degener, Sebastian A1 - Hille, Falk A1 - Baeßler, Matthias T1 - A living lab for Structural Health Monitoring at the Nibelungen Bridge Worms for Transfer Learning of Structural Dynamics N2 - The Nibelungen Bridge in Worms, Germany has been selected as a national demonstration structure for advanced non-destructive testing (NDT) and structural health monitoring concepts to extend the lifetime of civil structures and to optimize O&M actions. Parts of the research that involves this bridge as a demonstrator belong to the focus area program SPP100+. In this program, the bridges SHM System has been extended and combined with an additional setup of vibration sensors. The used digital smart sensor with pre-processing functions, the arrangement of the sensors at the structure and additional edge computing capability allows the investigation of transfer learning and other methods directly into the real structure. The living lab with seven triaxial accelerometers can be reconfigured in real-time and adjusted to the needs of AI models for classification. The comparison with the existing conventional SHM sensors has been made possible by hardware synchronization to the existing SHM System and collocating sensors at similar positions, so that a hardware exchange can be an investigated use-case for the transfer learning. During idle times, the system collects vibration data like a conventional SHM system. T2 - 10th European Workshop on Structural Health Monitoring (EWSHM 2024) CY - Potsdam DA - 10.06.2024 KW - Nibelungen Bridge KW - Living Lab KW - Transfer Learning KW - Transfer Structures KW - Modal Analysis PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-612810 UR - https://www.ndt.net/search/docs.php3?id=29853 DO - https://doi.org/10.58286/29853 SN - 1435-4934 VL - 29 IS - 7 SP - 1 EP - 8 PB - NDT.net GmbH & Co. KG CY - Mayen AN - OPUS4-61281 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Simon, Patrick A1 - Baeßler, Matthias ED - Rogge, Andreas ED - Meng, Birgit T1 - Temperatureinfluss auf Strukturmonitoring – Aktuelle Versuche N2 - Strukturmonitoring kann wertvolle Daten für die Zustandsbewertung und Schadensdetektion von Infrastrukturbauwerken liefern. Umgebungsbedingungen wie die Temperatur beeinflussen die Bauwerke und somit die Messdaten jedoch erheblich. Um Methoden für den Umgang mit Temperatureinflüssen zu entwickeln, wurden an der BAM Versuche an Stahlbeton- und Asphaltbalken unter kontrollierten Temperaturen von -40 °C bis 60 °C und definierten Schädigungen durchgeführt. Die Daten ermöglichen die Erforschung und Validierung neuer, auch unter Temperatureinfluss zuverlässiger Methoden des Strukturmonitorings. T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM Green Intelligent Building CY - Berlin, Germany DA - 16.10.2024 KW - Strukturmonitoring KW - Temperatureinfluss KW - Infrastrukturbauwerke KW - Stahlbeton- und Asphaltbalken PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-613289 SN - 978-3-9818564-7-7 SP - 294 EP - 302 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-61328 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Ramasetti, Eshwar Kumar A1 - Herrmann, Ralf A1 - Degener, Sebastian A1 - Baeßler, Matthias T1 - Development of generic AI models to predict the movement of vehicles on bridges N2 - For civil, mechanical, and aerospace structures to extend operation times and to remain in service, structural health monitoring (SHM) is vital. SHM is a method to examining and monitoring the dynamic behavior of essential constructions. Because of its versatility in detecting unfavorable structural changes and enhancing structural dependability and life cycle management, it has been extensively used in many engineering domains, especially in civil bridges. Due to the recent technical developments in sensors, high-speed internet, and cloud computing, data-driven approaches to structural health monitoring are gaining appeal. Since artificial intelligence (AI), especially in SHM, was introduced into civil engineering, these modern and promising methods have attracted significant research attention. In this work, a large dataset of acceleration time series using digital sensors was collected by installing a structural health monitoring (SHM) system on Nibelungen Bridge located in Worms, Germany. In this paper, a deep learning model is developed for accurate classification of different types of vehicle movement on the bridge from the data obtained from accelerometers. The neural network is trained with key features extracted from the acceleration dataset and classification accuracy of 98 % was achieved. KW - Structural Health Monitoring KW - Artifical Intelligence KW - Machine Learning KW - Nibelungen Bridge PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-620289 DO - https://doi.org/10.1016/j.prostr.2024.09.307 VL - 64 SP - 557 EP - 564 PB - Elsevier B.V. AN - OPUS4-62028 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Pimienta, Pierre A1 - McNamee, Robert A1 - Robert, Fabienne A1 - Boström, Lars A1 - Huang, Shan-Shan A1 - Mróz, Katarzyna A1 - Davie, Colin A1 - Mohaine, Siyimane A1 - Alonso, Maria Cruz A1 - Bodnarova, Lenka A1 - Bosnjak, Josipa A1 - Dal Pont, Stefano A1 - Dao, Vinh A1 - Dauti, Dorjan A1 - Dehn, Frank A1 - Felicetti, Roberto A1 - Hager, Izabela A1 - Hela, Rudolf A1 - Hozjan, Tomaz A1 - Juknat, Michael A1 - Jumppanen, Ulla-Maija A1 - Kirnbauer, Johannes A1 - Kolsek, Jerneja A1 - Korzen, Manfred A1 - Lakhani, Hitesh A1 - Lion, Maxime A1 - Lo Monte, Francesco A1 - Maluk, Cristian A1 - Meftah, Fekri A1 - Miah, Md Jihad A1 - Millard, Alain A1 - Mindeguia, Jean-Christophe A1 - Moreau, Bérénice A1 - Msaad, Yahia A1 - Ozawa, Mitsuo A1 - Pesavento, Francesco A1 - Pham, Duc Toan A1 - Pistol, Klaus A1 - Rickard, Ieuan A1 - Rodrigues, Joao Paulo Correia A1 - Roosefid, Mohsen A1 - Schneider, Martin A1 - Sharma, Umesh Kumar A1 - Sideris, Kosmas A1 - Stelzner, Ludwig A1 - Weber, Benedikt A1 - Weise, Frank T1 - Recommendation of RILEM TC 256-SPF on fire spalling assessment during standardised fire resistance tests: complementary guidance and requirements N2 - The recommendation is based on the co-authors’ work organized by the RILEM TC 256-SPF “Spalling of concrete due to fire: testing and modelling”. It aims to provide useful information, guidance and best practices in fire spalling assessment to laboratories that perform large-scale tests based on fire resistance test standards. It provides guidance on the spalling observation techniques during testing, as well as post-test spalling quantification/assessment methods. This document is intended to be used in conjunction with the fire resistance test standards, e.g. EN 1363-1 and ISO 834-1. KW - Concrete KW - Fire spalling KW - Large scale tests KW - Standardised fire resistance tests PY - 2024 DO - https://doi.org/10.1617/s11527-023-02248-z SN - 1871-6873 VL - 57 IS - 1 SP - 1 EP - 12 PB - Springer CY - Dordrecht AN - OPUS4-59288 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Pimienta, Pierre A1 - McNamee, Robert A1 - Hager, Izabela A1 - Mróz, Katarzyna A1 - Boström, Lars A1 - Mohaine, Siyimane A1 - Huang, Shan-Shan A1 - Mindeguia, Jean-Christophe A1 - Robert, Fabienne A1 - Davie, Colin A1 - Felicetti, Roberto A1 - Miah, Md Jihad A1 - Lion, Maxime A1 - Lo Monte, Francesco A1 - Ozawa, Mitsuo A1 - Rickard, Ieuan A1 - Sideris, Kosmas A1 - Alonso, Maria Cruz A1 - Millard, Alain A1 - Jumppanen, Ulla-Maija A1 - Bodnarova, Lenka A1 - Bosnjak, Josipa A1 - Dal Pont, Stefano A1 - Dao, Vinh A1 - Dauti, Dorjan A1 - Dehn, Frank A1 - Hela, Rudolf A1 - Hozjan, Tomaz A1 - Juknat, Michael A1 - Kirnbauer, Johannes A1 - Kolsek, Jerneja A1 - Korzen, Manfred A1 - Lakhani, Hitesh A1 - Maluk, Cristian A1 - Meftah, Fekri A1 - Moreau, Bérénice A1 - Pesavento, Francesco A1 - Pham, Duc Toan A1 - Pistol, Klaus A1 - Correia Rodrigues, Joao Paulo A1 - Roosefid, Mohsen A1 - Schneider, Martin A1 - Sharma, Umesh Kumar A1 - Stelzner, Ludwig A1 - Weber, Benedikt A1 - Weise, Frank T1 - Recommendation of RILEM TC 256-SPF on the method of testing concrete spalling due to fire: material screening test N2 - The recommendation is based on the coauthors’ work organized by the RILEM TC 256-SPF ‘‘Spalling of concrete due to fire: testing and modelling’’. The Committee has defined two types of screening tests for characterization of concrete propensity to fire spalling: Material screening tests and Product screening tests. Definitions of both types of tests are given in the paper. The following recommendations apply to Material screening tests. The material screening tests described in these recommendations are a set of minimum requirements to test concrete spalling propensity (for example, the minimal specimen size). This document covers the aspects of concrete characterization, specimen geometries, storage conditions, test methods and measured parameters. KW - Concrete KW - Fire Spalling KW - Screening tests KW - High temperature PY - 2023 DO - https://doi.org/10.1617/s11527-023-02202-z VL - 56 IS - 9 SP - 1 EP - 12 PB - Springer Science and Business Media LLC AN - OPUS4-60635 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schraut, Katharina A1 - Adamczyk, Burkart A1 - Simon, Sebastian A1 - von Werder, Julia A1 - Meng, Birgit A1 - Stephan, D. A1 - Kargl, F. A1 - Adam, Christian T1 - Formation and chemical stabilisation of tricalcium-silicate during solidification from the melt of post-treated metallurgical slags N2 - Tricalcium-silicate (C3S) or Alite is the most important mineral in Portland cement. Since pure tricalcium-silicate is only stable above temperatures of 1250 °C, its decomposition has to be prevented technically by fast cooling after the sintering process. At room temperature, the decomposition velocity is very slow so that metastable tricalcium-silicate is obtained. Although the mechanisms of clinker phase formation during burning process of Portland cement in a rotary kiln were solved and improved over the years, in view of possible economic and ecological benefits current projects aim to produce clinker phases from metallurgical slags. Recent studies discovered that the mineral phase which remained after a reducing treatment and separation of formed metallic iron from molten Linz-Donawitz (LD-) slags contained about 60 wt.% Alite despite it was cooled slowly. Because the results could be verified using slags from different origins and varying cooling velocities a chemical stabilisation of the Alite can be assumed. First tests in mortars indicate that workability, hardening and solid state properties are comparable with an ordinary Portland cement. An application of the observed phenomenon in cement production requires enhanced knowledge about formation and stabilisation conditions of Alite during crystallisation from melts in contrast to the sintering reactions in conventional Portland cement production. Therefore, this study focuses on the stabilisation mechanisms of Alite in consolidating melts. Samples from different melting experiments are analysed to determine stabilising factors. T2 - 15th International Congress on the Chemistry of Cement CY - Prag, Czech Republic DA - 16.09.2019 KW - Tricalcium-silicate KW - Portland Cement KW - Alite KW - Steelmaking slag PY - 2019 SP - Paper 492, 1 EP - 10 AN - OPUS4-49050 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Weise, Frank T1 - AKR an Betonfahrbahndecken - ausgewählte Einflussgrößen und neuartige AKR-Vermeidungsstrategie N2 - In den letzten Jahren sind im deutschen Bundesautobahnnetz vermehrt Schäden an vor 2005 hergestellten Betonfahrbahndecken aufgetreten, die mit einer Alkali-Kieselsäure-Reaktion(AKR) in Verbindung gebracht werden. Vor diesem Hintergrund werden in diesem Beitrag zunächst die Voraussetzungen und ausgewählte Einflussgrößen für eine schädigende AKR aufgezeigt. Besondere Aufmerksamkeit wird dabei der Rolle des Tausalzeintrags durch den Winterdienst bei Betonfahrbahndecken geschenkt. So wird mit Löseversuchen in 1 M KOH-Lösung zweier Gesteinskörnungen bei 80 °C gezeigt, dass mit zunehmender NaCI-Zugabe die Löslichkeit von SiÖ2 zunimmt und die von AI2O3 eine Verminderung erfährt. Basierend auf dem so exemplarisch erbrachten Nachweis für die Verstärkung der schädigenden AKR durch das Tausalz wird die Notwendigkeit und Richtigkeit der Durchführung von AKR-Betonversuchen mit Alkalizufuhr im ARS 04/2013 zur zukünftigen Vermeidung von AKR-Schäden an Betonfahrbahndecken im Rahmen von Neubau- und Erneuerungsmaßnahmen im Bundesfernstraßennetz belegt. Zusätzlich durchgeführte WS-Grundprüfungen nach dem ARS 04/2013 mit den beiden Gesteinskörnungen der Löse versuche veranschaulichen, dass die nach der Alkali-Richtlinie des DAfStb als unbedenklich eingestuften Gesteinskörnungen bei den Betonversuchen mit Alkalizufuhr durchaus als alkaliempfindlich bewertet werden können. Dies wiederum führt zu einer Verminderung der für den Betonstraßenbau verfügbaren Gesteinskörnungen. Vor diesem Hintergrund wird nach neuartigen AKR-Vermeidungsstrategien gesucht, die auch eine Verwendung der als grenzwertig alkaliempfindlich eingestuften Gesteinskörnungen erlaubt. Einen möglichen Lösungsansatz stellt in diesem Kontext die Innenhydrophobierung des Fahrbahndeckenbetons dar. Es soll so durch die Behinderung des Feuchte- und Tausalzeintrags in den Beton der AKR-Schädigungsprozess signifikant vermindert werden. Für die Bewertung der Leistungsfähigkeit der Innenhydrophobierung zur Vermeidung bzw. Verminderung einer schädigenden AKR in Betonfahrbahndecken wird zurzeit im Aufträge der BASt an der BAM ein Forschungsvorhaben bearbeitet. Im Rahmen dieses Beitrags werden erste Ergebnisse dieses Projekts vorgestellt. So wird exemplarisch an einem Oberbeton (D > 8)/Unterbeton und einem Oberbeton 0/8 mit einer alkaliempfindlichen Gesteinskörnung der Einfluss zweier Hydrophobierungsmittel auf die Frisch- und Festbetoneigenschaften ganzheitlich aufgezeigt und bewertet. Bei Letzteren stehen zunächst die mechanischen und hygrischen Parameter sowie der Frost-Tausalzwiderstand im Vordergrund. In einem weiteren Schritt wird der Einfluss beider Hydrophobierungsmittel auf die schädigende AKR mittels AKR-Betonversuchen mit Alkalizufuhr beleuchtet. Dabei gelangen ergänzend zur Beurteilung des Tausalzeintrags die Laser-Induced Breakdown Spectroscopy (LIBS) und zur Bewertung der Ausprägung der AKR und sekundären Ettringitbildung (SEB) die Dünnschliffmikroskopie zum Einsatz. T2 - 9. Betonfachtagung 2019 CY - Berlin, Germany DA - 12.11.2019 KW - AKR KW - Betonfahrbahn KW - Innenhydrophobierung KW - Tausalzeintrag KW - AKR-Betonversuche PY - 2019 AN - OPUS4-50218 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - von Werder, Julia A1 - Simon, Sebastian A1 - Meng, Birgit ED - Gemrich, J. T1 - Hydrothermal Treatment of Ultra-High-Performance Concrete: Mechanical Properties and Phase Composition N2 - The advantages of treating prefabricated components made of Ultra-High-Performance Concrete (UCPC) at 90 °C are largely recognized, while hydrothermal treatment at 185 °C and the corresponding saturation pressure of 1.1 MPa, in contrast, is not applied in building practice so far and was studied only by a few researchers. In the research presented, the parameters pre-storage-time before treatment and dwell time in the autoclave were systematically varied. The results illustrate in which way compressive strength increases with the duration of treatment. Already samples which were only heated up and immediately cooled down show an increase in strength compared to the 28-day reference of about 10 %. After 20 h the maximum increase of about 25 % is reached. Interestingly the compressive strength of samples treated very long hardly decreases. It can be therefore concluded that for the composition investigated the achievable mechanical strength is not severely sensitive regarding the duration of the treatment. Also, pre-storage times before autoclaving longer than 0.5 days showed no significant impact on strength development. The phase composition measured by XRD exhibits significant changes compared to the reference. The amount of ettringite and portlandite have vanished, the cement clinker phases are substantially decreased and hydroxylellestadite and hydrogarnet are formed as new phases. The increase in strength can be assigned to an improved pozzolanic and hydraulic reaction. Contradictory to literature, there was found no tobermorite, a mineral which is known to be susceptible for disintegration at Long autoclaving duration. This explains why no significant strength loss appeared. T2 - 15th International Congress on the Chemistry of Cement CY - Prague, Czech Republik DA - 16.09.2019 KW - Hydrothermal treatment KW - UHPC KW - Phase composition KW - Mechanical strength PY - 2019 SN - 2523-935X SP - 1 EP - 11 AN - OPUS4-49481 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Priebe, Nsesheye Susan A1 - Gluth, Gregor A1 - Vogler, Nico A1 - Simon, Sebastian A1 - Kühne, Hans-Carsten ED - Serdar, M. ED - Stirmer, N. ED - Provis, J. T1 - Investigation of calcined brick clays from Central Germany for use as a sustainable pozzolan N2 - The production of Portland cement causes a substantial environmental impact, since the calcination of limestone results in high emissions of carbon dioxide. The use of supplementary cementitious materials such as calcined clays as partial replacement for Portland cement offers a solution to limit this environmental impact. This paper investigates four clays from deposits in central Germany with the aim of obtaining pozzolans for the production of Portland-pozzolana cement. The results obtained show that the calcined clays possess pozzolanic properties, which differ depending on calcination temperature and the relative amounts of Kaolinite and 2:1 clay minerals. T2 - International Conference on Sustainable Materials, Systems and Structures (SMSS 2019) CY - Rovinj, Croatia DA - 20.03.2019 KW - Supplementary cementitious materials KW - Calcined clays KW - Blended cements KW - Brick clays KW - Illitic clays PY - 2019 SN - 978-2-35158-223-7 N1 - Geburtsname von Priebe, Nsesheye Susan: Msinjili, N. S. - Birth name of Priebe, Nsesheye Susan: Msinjili, N. S. VL - 1 SP - 462 EP - 469 PB - RILEM Publications CY - Paris AN - OPUS4-47586 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Meng, Birgit A1 - Simon, Sebastian T1 - Characterization of Alkali-Silica Reaction Products by means of Raman Spectroscopy before and after Application of Accelerated Tests N2 - Alkali silica reaction (ASR) is a major concrete durability problem resulting in significant maintenance and reconstruction costs for concrete infrastructures all over the world. To determine whether an aggregate is potentially reactive, accelerated concrete tests are used. Aim of this study is the chemical and microstructural characterization of ASR-products formed under the performance conditions of motorway pavements and during subsequent tests on the remaining ASR susceptibility. Samples were taken from concrete motorway pavements. Some of the samples already showed first indications for beginning damages whereas others showed deteriorations only after applying a performance testing procedure for the estimation of future risk of ASR damage. In a first step ASR-products were identified by polarized light microscopy in thin sections. The reaction products where then analyzed by Raman Spectroscopy and finally the chemical composition of the ASR-products was identified by SEM with EDX. The results indicate that most reaction products show an increasing Ca/Si-ratio with progressive crack length. If an ASR-product develops inside an aggregate and moves through the cement paste, it has a high (Na+K)/Si-ratio at the beginning which decreases with increasing distance from its place of origin. The Raman spectra of the ASR-products are characterized by two broad bands indicating specific Q-species of different amorphous gel networks. Within the scope of the analysis distinctions in the microstructure and the chemical composition of the ASR-gels were detected relating to various conditions of accelerated testing. T2 - 15th International Congress on Chemistry of Cement CY - Prague, Czech Republic DA - 16.09.2019 KW - Alkali-silica reaction KW - Raman microscopy KW - Microstructure KW - Concrete motorway pavements KW - Performance test PY - 2019 AN - OPUS4-49527 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - RPRT A1 - Gehrke, M. A1 - Stephan, D. A1 - Weigel, Sandra T1 - Entwicklung einer Prüfsystematik zur Identifizierung der Bitumenart und der verwendeten Modifizierungsmittel in einem Ausbauasphalt N2 - Development of a test system for identifying the bitumen type and the modifier used in a reclaimed asphalt Da Polymer-, Gummi-, wachs- und mehrfachmodifizierte Bitumen seit Jahren im Asphaltstraßenbau eigesetzt werden, kommen diese vermehrt im Ausbauasphalt vor. Zur Bewertung des Ausbauasphalts ist es daher notwendig, die Modifizierungen an der Mischanlage zu identifizieren. Die Ausbildung des Bindemittelsacks beim Erweichungspunkt Ring und Kugel ist charakteristisch für die Modifizierung. Hierdurch können wachsmodifizierte Bitumen (WmB) recht präzise und Polymermodifizierten Bitumen (PmB) teilweise identifiziert werden. Mittels Differential Scanning Calorimetry (DSC) werden die Schmelztemperaturen der Wachse erfasst. Hierdurch können WmB identifiziert und die Wachsarten unterschieden werden. Die Analytik mittels Dynamischem Scherrheometer (DSR) startet mit der Bestimmung der Äquisteifigkeitstemperatur EG*T. Bei EG*T werden Frequenz-, Amplituden- und MSCR-Tests durchgeführt. Die Grenze des LVE-Bereichs dient der Identifizierung von WmB. Anhand der Kennwerte bei 0,1 Hz können PmB erkannt werden. Die Rückformung (MSCRT) dient der Identifizierung von Mehrfachmodifizierungen. Da Gummimodifizierte Bitumen (GmB) bei der Extraktion erkannt werden, können alle Modifizierungsarten identifiziert werden. In den FTIR-Spektren (Fourier-Transformations-Infrarotspektroskopie) der modifizierten Bitumen verursachen einige Polymere und Wachse charakteristische Banden, wodurch diese erkannt werden. Die Identifizierung der übrigen Additive erfolgt mithilfe einer multivariaten Auswertung, wodurch mit Ausnahme der GmB (nicht erforderlich) alle Additive erkannt werden. An Stichproben konnte zudem eine Abgrenzung von Mehrfachmodifizierungen sowie eine Abschätzung der Zugabemenge erreicht werden. DSR und FTIR ermöglichen beide eine schnelle, einfache und zielsichere Identifizierung der Bitumenmodifizierungen. Durch die FTIR-Analytik können die Modifizierungen mit der größtmöglichen Präzision bestimmt werden. Die DSR-Analytik erlaubt dafür zusätzlich eine baupraktische Bewertung der Bindemittel. As polymer, rubber, wax and multi-modified bitumen are used for asphalt road construction since many years, they increasingly occur in reclaimed asphalt. To assess the reclaimed asphalt, it is therefore necessary to identify the modifications in the mixing plants. The formation of the binder bag at softening point ring and ball is characteristic for modification. In this way, wax modified bitumen (WmB) can be identified rather precisely and to a less extent polymer modified bitumen (PmB) can also be identified. Differential scanning calorimetry (DSC) is used to record the melting temperatures of the waxes. In this way, WmB can be identified and a differentiation can be made between the wax types. The analysis by means of the dynamic shear rheometer (DSR) starts with the determination of the equi-stiffness temperature EG*T. Frequency-, amplitude- and MSCR-tests are performed at EG*T. The limit of the LVE range is used to identify WmB. PmB can be identified based on the characteristic values at 0.1 Hz. Creep recovery (MSCRT) is used to identify multi-modifications. As rubber modified bitumen (GmB) is identified on extraction, all types of modification can therefore be identified. Several polymers and waxes cause characteristic bands in the FTIR spectra (Fourier Transform Infrared spectroscopy) of modified bitumen, which enables the identification of these additives. The other additives except the GmB (not necessary) can be identified by means of multivariate model. Further, due to random evaluations, the differentiation between single- and multi-modification as well as the estimation of the content of some additives is possible. DSR and FTIR both enable fast, simple and accurate identification of the bitumen modification. The modification can be determined with the greatest possible precision by using FTIR analysis. On the other hand, DSR analysis allows additional practical assessment of the binder on site. KW - Asphaltstraße (Oberbau) KW - Bitumen KW - Bitmuinöses Mischgut KW - Mechanik KW - Schicht PY - 2021 UR - https://bast.opus.hbz-nrw.de/frontdoor/index/index/docId/2586 SN - 978-3-95606-658-0 SN - 0943-9323 VL - Reihe S: Straßenbau (168) SP - 1 EP - 151 PB - Fachverlag NW in der Carl Ed. Schünemann KG CY - Bremen AN - OPUS4-54971 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Herrmann, Ralf T1 - Managing Structural Health Monitoring with the Research Data Management Platform BAM Data Store N2 - Structural Health Monitoring (SHM) is an interdisciplinary challenge involving the assessment and prediction of the condition of civil structures, such as bridges, based on measurements and models. This presentation provides insight into how the BAM Data Store is used to represent a SHM project including the metadata and the monitoring data, itself. It describes the structure of the core elements of a typical SHM and introduces metadata profiles. This enables linking objects within the BAM Data Store to create a hierarchical structure. N2 - Structural Health Monitoring (SHM) ist eine interdisziplinäre Aufgabe bei der es um die Bewertung und Zustandsprognose von Bauwerken, wie z. B. Brücken, auf der Grundlage von Messungen und Modellen geht. Die Präsentation gibt einen Einblick in die Verwendung des BAM Data Stores zur Abbildung eines SHM Projekts zum Datenmanagement aller relevanten Metadaten und der Monitoringdaten selbst. Es werden die Struktur der Kernelemente eines typischen SHM beschrieben und Metadatenprofile für diese vorgestellt. Im BAM Data Store werden damit die strukturierte Verknüpfung von Objekten ermöglicht, um eine hierarchische Struktur zu erzeugen. T2 - Data Store Days 2025 CY - Berlin, Germany DA - 09.04.2025 KW - Structural Health Monitoring (SHM) KW - BAM Data Store KW - Verkehrsinfrastrukturen PY - 2025 AN - OPUS4-62942 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schneider, Ronald T1 - SysPark: a software tool for system-wide adaptive planning of inspections of turbine support structures in offshore wind farms N2 - Fatigue is one of the main deterioration processes affecting the performance of welded steel support structures of wind turbines in offshore wind farms. In this contribution, we present a probabilistic physics-based fatigue deterioration model of a wind farm that accounts for the stochastic dependence among the fatigue behavior of different hotspots at turbine and wind farm level. The dependence exists because of uncertain common influencing factors such as similar material properties, fabrication qualities and load conditions. These system effects signify that an inspection of one hotspot provides indirect information of the condition of the remaining hotspots and thus enable an optimization of the inspection effort for a wind farm. The wind farm model consists of two levels: A turbine support structure (level 1 system model) is represented by its fatigue hotspots and their stochastic dependence. The fatigue performance of a hotspot is described by a probabilistic fracture mechanics (FM) fatigue model. The probabilistic model of the parameters of the FM fatigue model is calibrated based on design data and is thus directly linked to the design of the turbine support structures. Dependence among the fatigue performances of different hotspots in a turbine support structure is modeled by introducing correlations between the stochastic parameters of the FM fatigue models. A wind farm (level 2 system model) consists of different turbine support structures (level 1 system models). Additional correlations are introduced at wind farm level to account for the dependence among the fatigue behavior of hotspots belonging to different turbine support structures. The wind farm model enables the computation of (marginal) hotspot fatigue reliabilities, system fatigue reliabilities of individual turbine support structures and the system fatigue reliability of an entire wind farm. The probabilistic model of the parameters of the two-level system model can be consistently updated with inspection outcomes using Bayesian methods. The updated probabilistic model of the model parameters then forms the basis for updating the estimates of the fatigue reliabilities. We implement the wind farm model in a software tool named SysPark. The tool provides the means for planning inspections at wind farm level using an adaptive reliability-based threshold approach. In this approach, the first inspection campaign is planned in the year before the fatigue failure rates of the hotspots with the lowest fatigue reliabilities exceed a threshold failure rate. Once inspection results become available, the probabilistic model of the parameters of the wind farm model is updated. If repairs are performed, the wind farm model is additionally modified to describe the behavior of the repaired hotspots. The updated and modified model then enables the planning of the next inspection campaign and so on. The software tool is demonstrated in a case study considering a generic wind farm consisting of turbines with jacket support structures. T2 - Wind Energy Science Conference (WESC 2021) CY - Online Meeting DA - 25.05.2021 KW - Fatigue deterioration KW - Offshore wind farm KW - Inspection planning PY - 2021 AN - OPUS4-52767 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Eichner, Lukas T1 - Probabilistische Systemidentifikation einer Versuchsstruktur für Substrukturen von Offshore-Windenergieanlagen mit statischen und dynamischen Messdaten N2 - In diesem Beitrag wird ein probabilistischer Ansatz zur Systemidentifikation für Tragstrukturen von Offshore-Windkraftanlagen vorgestellt. Der Schwerpunkt der Forschung liegt auf der Integration von globalen Systemantworten in Form von Eigenfrequenzen und -formen sowie Verschiebungen und Dehnungen als lokale Messdaten. Die unterschiedlichen Daten werden kombiniert für die Aktualisierung der Parameter eines Finite-Elemente-Modells genutzt. Zu diesem Zweck wird ein probabilistischer Ansatz nach Bayes verfolgt, um Vorwissen sowie Unsicherheiten einzubeziehen. Die Methodik wird bei einer Versuchsstruktur angewandt, die eine Jacket-Substruktur von Offshore-Windenergieanlagen nachbildet. Eine Systemidentifikation mit Hilfe von Überwachungsdaten ist wertvoll für Jacket-Substrukturen, da eine Zustandsanalyse für die Gewährleistung der strukturellen Integrität unerlässlich ist, aber hinsichtlich der schwierigen Offshore-Bedingungen möglichst effizient sein muss. In diesem Zusammenhang schafft diese Arbeit die Grundlage für eine Schadenserkennung, eine verbesserte Vorhersage der Ermüdungslebensdauer und optimierte Instandhaltungsstrategien. Während das Modell hinsichtlich der statischen Messdaten erfolgreich aktualisiert werden kann, sind Schwierigkeiten bei der Identifizierung der dynamischen Systemeigenschaften erkennbar. T2 - 8. VDI-Fachtagung Baudynamik 2025 CY - Würzburg, Germany DA - 02.04.2025 KW - Systemidentifikation KW - Versuchsstruktur KW - Jacket KW - Offshore-Windenergie PY - 2025 AN - OPUS4-62880 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Andrés Arcones, Daniel T1 - Incorporating model form uncertainty in digital twins for reliable parameter updating and quantitites of interest analysis N2 - With the rapid adoption of Digital Twins in recent years, simulation models designed to replicate real-world physical systems have become increasingly common. To achieve accurate representations, it is typically necessary to update model parameters based on observations collected from sensors or measurements of the physical asset. However, no model can fully capture the infinitely complex nature of reality. As a result, quantifying the uncertainty in model predictions is essential for reliable decision-making. Bayesian updating frameworks provide an appealing approach for parameter calibration, inherently accounting for such uncertainties. One often-overlooked source of error is model form uncertainty. This type of uncertainty arises from the fundamental discrepancies between the model and reality, stemming from the assumptions and simplifications made during model construction. Ignoring model form uncertainty can lead to overly confident predictions that fail to accurately reflect sensor observations. To address this, we propose an embedded model form uncertainty framework that attributes the model variability to a stochastic extension of the model's latent parameters. This approach enables the quantification of uncertainties that can be represented by a variation in the model parameters. Of particular interest are scenarios involving noisy observations or additional discrepancies that cannot be directly integrated into the model. By incorporating uncertainty through the parameters, this method not only quantifies uncertainty in predictions but also propagates model form uncertainty to other Quantities of Interest (QoI) that rely on the same model or its parameters. Consequently, QoI computations yield more reliable values, accounting for the potential uncertainties introduced by imperfect models during parameter updating. Moreover, this approach facilitates a more comprehensive statistical analysis of QoI distributions, offering deeper insights into the model's reliability and highlighting areas for potential improvement. By incorporating model form uncertainty, decision-makers can achieve a more robust and nuanced understanding of system behavior and prediction quality. T2 - 95th Annual Meeting oft eh International Association of Applied Mathematics and Mechanics (GAMM) CY - Poznan, Poland DA - 07.04.2024 KW - Unsicherheiten Quantifizierung KW - Brückenüberwachung KW - Digitaler Zwilling PY - 2025 AN - OPUS4-62972 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schraut, Katharina T1 - Formation and hydraulic reactivity of an alite rich material from post treated basic oxygen furnace slag N2 - Basic oxygen furnace slag (BOFS) is a by-product of steelmaking of which about 10.4 Mt are produced annually in the EU. BOFS is mostly used in road construction, earthwork and hydraulic engineering. However, in this use, the iron bound in BOFS is lost and the opportunity to produce higher value products from BOFS is forgone. In recent decades, many researchers have investigated a thermochemical process to reduce iron oxides to metallic iron in molten BOFS. The metallic iron formed separates from the reduced slag due to its higher density and can be recovered. An advantage of this process is that simultaneously the chemical composition of the reduced slag is adapted to that of the Portland cement clinker and the hydraulic reactive mineral alite is formed. In this study, BOFS was reduced in a small-scale electric arc furnace using petrol coke as reducing agent, and the hydraulic properties of the reduced, low-iron BOFS were investigated. Despite a chemical and mineralogical composition similar to that of Portland cement clinker, the reduced BOFS produced less heat of hydration, and its reaction was delayed compared to Portland cement. However, the addition of gypsum, as is also done in cement production from Portland cement clinker, has been found to accelerate the hydration rate of reduced BOFS. Further research to improve the hydraulic properties of the reduced slag is essential. If successful, the production of a hydraulic binder and crude iron from BOFS could have economic and ecological benefits for both the cement and steel industry. T2 - GeoMin Köln 2022 CY - Cologne, Germany DA - 11.09.2022 KW - BOFS KW - Portland Cement KW - Hydraulic reactivity PY - 2022 AN - OPUS4-56080 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Klimek, Andre A1 - Hothan, Sascha A1 - Rogge, Andreas T1 - Das Abplatzverhalten von Beton im Zusammenhang mit dem Maßstabseffekt N2 - Beton, als aktuell am meisten verwendeter Baustoff ist nicht brennbar und weist zudem eine sehr geringe Temperaturleitfähigkeit auf. Er eignet sich somit gut für den baulichen Brandschutz. Jedoch neigt Beton im Brandfall zu explosionsartigen Abplatzungen, die zu einer Reduzierung des tragfähigen Querschnitts und sogar zum Versagen des Bauteils führen können. Derzeit werden thermomechanische und thermohydraulische Schädigungsprozesse als die zwei maßgeblichen Ursachen für explosionsartige Abplatzungen angesehen. Diese Schädigungsprozesse sind unter anderem abhängig von der Prüfkörpergröße, dem Wasser-Zement-Wert, der Porosität, der Permeabilität und dem Bewehrungsgrad des Bauteils. Im Rahmen des Vortrags werden die Forschungsarbeiten zum Maßstabseffekt des Abplatzverhaltens von Betonen bei Brandbeanspruchung präsentiert. Zu diesem Zweck wurden Betonprüfkörper aus sechs verschiedenen Betonmischungen in jeweils drei Prüfkörpergrößen einseitig, ohne Behinderung der thermischen Ausdehnung und ohne externe Last im Tunnelbrandprüfstand der BAM untersucht. Dieser unikale Prüfstand ermöglicht die Brandprüfung unterschiedlicher Prüfkörpergrößen unter vergleichbaren Brandbedingungen sowie die simultane Prüfung mehrerer kleinformatiger Betonprüfkörper. Das präsentierte, laufende Promotionsvorhaben basiert auf einem von der DFG geförderten Forschungsvorhaben und darauf aufbauenden Folgeuntersuchungen. Die Ergebnisse des DFG-Vorhabens zeigen einen deutlichen Maßstabseffekt mit einer starken Verringerung der Abplatztiefen bei einer Reduzierung der Prüfkörpergröße. Des Weiteren ist das Abplatzverhalten stark von der Betonmischung abhängig. Vor dem Hintergrund der Ressourcenschonung und Kostenreduzierung verfolgen die auf dem DFG-Vorhaben aufbauenden Untersuchungen das Ziel, das Abplatzverhalten großformatiger Betonprüfkörper durch kleinformatige Betonprüfkörper mit angepassten Randbedingungen nachzustellen. Hierfür wurden zwei Betonmischungen des DFG-Vorhabens verwendet. Die Ergebnisse zeigen, dass durch eine Anpassung der Versuchsrandbedingungen dem Maßstabseffekt entgegengewirkt werden kann. T2 - 7. Symposium 'Heißbemessung - Structural Fire Engineering' CY - Online meeting DA - 14.09.2021 KW - Maßstabseffekt KW - Beton KW - Abplatzen KW - Brand PY - 2021 SP - 1 EP - 12 PB - Technische Universität Braunschweig AN - OPUS4-53528 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Weise, Frank A1 - Fladt, Matthias T1 - Innenhydrophobierung - neuartige AKR-Vermeidungsstrategie bei Betonfahrbahndecken N2 - Um die zunehmenden AKR-Schäden an Betonfahrbahnen im deutschen Autobahnnetz zukünftig zu vermeiden, wurden mit dem ARS 04/2013 verbindliche Eignungsprüfungen zum Ausschluss alkaliempfindlicher Gesteinskörnungen bei Neubau- und Erhaltungsmaßnahmen eingeführt. Dies führte zu einer deutlichen Reduzierung der geeigneten Gesteinskörnungen. Vor diesem Hintergrund soll durch die Zugabe eines Innenhydrophobierungsmittels während der Betonherstellung grenzwertig alkaliempfindliche Gesteinskörnung nutzbar gemacht werden. Die AKR-Vermeidungsstrategie basiert dabei auf der signifikanten Reduzierung des Eindringens von Wasser und Tausalzlösung in den Fahrbahndeckenbeton. In einem im Aufträge der BASt an der BAM durchgeführten Forschungsvorhaben wurde die Leistungsfähigkeit verschiedener Hydrophobierungsmittel für diesen Einsatzzweck grundhaft untersucht. In dem Beitrag wird exemplarisch die Leistungsfähigkeit eines geeigneten Hydrophobierungsmittels in einem Waschbeton mit einer sehr alkaliempfindlichen Grauwacke aufgezeigt. Das Spektrum der Laboruntersuchungen reicht dabei von AKR-Betonversuchen mit Alkalizufuhr sowie den aufbauend durchgeführten mikroskopischen Untersuchungen zur Bewertung des AKR-Schädigungspotenzials über die Analyse des Feuchte- und Tausalzeintrags bis zur Ermittlung der mechanischen Eigenschaften und des Frost-Tausalz-Widerstands. Abschließend wird der noch vorhandene Forschungsbedarf zur Überführung dieser neuen AKR-Vermeidungsstrategie in die Praxis aufgezeigt. N2 - In order to avoid the increasing ASR damage to concrete pavements in the German motorway network in the future, binding suitability tests for the exclusion of alkali-sensitive aggregates in new construction and maintenanee measures were introduced with ARS 04/2013. This led to a significant reduetion in the number of suitable aggregates. Against this background, borderline alkali-sensitive aggregates are to be made usable by adding an internal water repellent during concrete easting. The ASR avoidance strategy is based on the signifi-cant reduetion of the penetration of water and de-icing salt solution into the concrete pavement. In a research project carried out at BAM on behalf of the BASt, the performance of various hydrophobing agents for this application was thoroughly investigated. In this contribution, the performance of a suitable water repellent in an exposed aggregate concrete with a very alkali-sensitive greywacke is shown as an example. The spectrum of laboratory investigations ranges from ASR concrete tests with alkali supply and the microscopic investigations carried out to evaluate the ASR damage potential, to the analysis of the moisture and de-icing salt penetration, to the determination of the mechanical properties and the freeze-thaw resistance. Finally, the still existing need for research for the transfer of this new ASR prevention strategy into practice is shown. KW - Betonfahrbahndecke KW - Alkali-Kieselsäure-Reaktion KW - Innenhydrophobierung PY - 2021 SN - 0039-2162 IS - 9.2021 SP - 730 EP - 738 PB - Kirschbaum Verlag GmbH AN - OPUS4-54554 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Unger, Jörg F. T1 - Combining material and structural design to reduce the global warming potential of concrete structures N2 - The creation of civil structures such as bridges, dams, and buildings involves a collaborative effort among various experts, each handling specific aspects of the process. Traditionally, this process is performed sequentially, i.e. starting with the structural design with assumptions on minimal material properties, and a subsequent material design within these limits. In the presentation, an alternative procedure is proposed that merges concrete mix design and structural simulations into a unified, progressive workflow. The design procedure is then reformulated as an optimization problem with constraints related to key performance indicators such as e.g. the load bearing capacity. Addressing uncertainties—whether inherent (aleatoric) or arising from incomplete knowledge (epistemic)—is crucial in any design endeavor. These uncertainties may stem from data used to calibrate physical models, from model simplifications or from machine learning models trained with limited amount of data that are used to bridge gaps in the workflow. Inverting the causal relations poses several challenges especially when these physics-based models do not provide derivatives/sensitivities or when design constraints are present. Our approach advocates for Variational Optimization, augmented by proposed extensions and carefully selected heuristics. Integrating the expertise and numerical methods from multiple experts is a challenging task in itself. The presentation discusses the use of workflow tools with a modularization of the computational methods. The presentation includes related challenges in the context of the FAIR principles (Findable, Accessible, Interoperable, Reusable). The design of a precast concrete beam is presented as an example to demonstrate the efficacy of our methodology. The objective is to minimize the environmental impact in terms of the global warming potential while fulfilling constraints related to the load-bearing capacity (Eurocode) as well as the demoulding time and the maximum temperature during hydration.The latter are computed from a macroscopic thermo-mechanical Finite Element simulation that is based on a hydration model on the paste level combined with homogenization procedures to obtain the macroscopic constitutive equations. Experimental data is used to perform a Bayesian calibration of these models. T2 - ECCOMAS CONGRESS 2024 CY - Lisbon, Portugal DA - 03.06.2024 KW - Performance oriented design KW - Black-box optimization under uncertainty KW - Probabilistic machine learning KW - Precast concrete KW - Mix design KW - Sustainable material design PY - 2024 AN - OPUS4-62108 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schönsee, Eric T1 - Investigations on multi-sensor data for monitoring volume flow during the printing process N2 - Extrusion based 3D concrete printing (3DCP) is a growing technology because of its high potential for automating construction and the new possibilities of design. In conventional construction methods, a sample is taken to be representative for one material batch. However, in 3DCP continuous mixing is used which results in variations during the mixing process. Therefore, one sample is not representative for the entire structure. This leads to the necessity of continuous and real-time process monitoring. This study focuses on the variations of pressure and temperature which are caused by changes in the material due to the ongoing mixing process. Changes in material, which is transported downstream, are influencing sensor signals in different positions with a time delay. In the following, the data is analysed to investigate if the changing material and the so caused change in pressure can be used to calculate volume flow. T2 - Digital Concrete 2024 CY - Munich, Germany DA - 04.09.2024 KW - Additive Manufacturing KW - In-line Monitoring KW - Volume Flow KW - Process Control PY - 2024 AN - OPUS4-61002 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - RPRT A1 - Recknagel, Christoph A1 - Eilers, M. A1 - Alte-Teigeler, R. A1 - Borchers, R. A1 - Commer, T. A1 - Gallai, G. A1 - Goldschmidt, M. A1 - Habiger, D. A1 - Karczewski, B. A1 - Koll, R.-J. A1 - Lorenz, S. A1 - Marossow, H. A1 - Rossi, M. A1 - Schneider, T. A1 - Seiffart, J. A1 - Staeck, M. A1 - Stark, S. A1 - Wehner, H. A1 - Willand, E. T1 - Hinweise für die Herstellung von Fahrbahnübergängen aus Poyurea oder Polyurethan für Ingenieurbauten - H FüPP N2 - Diese Hinweisbroschüre erläutert allgemeine Planungsvoraussetzungen und Dimensionierungsregelungen, Baugrundsätze und Zulassungsbedingungen zur Anwendung innovativer Belagsdehnfugensysteme (Fahrbahnübergangskonstruktionen) in hochbeanspruchten Verkehrsflächen des Bundesfernstraßenbereiches. Alle planungsrelevanten, baustoffrelevanten, versuchstechnische, qualitätssichernden und baupraktischen Aspekte werden zur Unterstützung der Straßenbauverwaltungen, der Lieferfirmen und Ausführungsbetriebe erläutert. Die Veröffentlichung stellt eine technische Analyse aus Erfahrungssammlungen und Auswertung praktischer Erkenntnisse dar. KW - Brückenbeläge KW - Fahrbahnübergänge KW - Dehnfugenkonstruktionen KW - technische und technologische Anforderungen PY - 2022 SN - 978-3-86446-355-6 VL - 778 SP - 1 EP - 47 PB - Forschungsgesellschaft für Straßen- und Verkehrswesen CY - Köln AN - OPUS4-59374 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Alte-Teigeler, R. A1 - Eilers, M. A1 - Recknagel, Christoph T1 - Hinweise und Erläuterungen zu den Zusätzlichen Technischen Vertragsbedingungen und Richtlinien für Ingenieurbauten Teil 6: Bauwerksausstattung Abschnitt 7: Fahrbahnübergänge aus Asphalt (ZTV-ING 6-7) sowie den TL BEL-FÜ und den TP BEL-FÜ N2 - Dieses Wissensdokument führt zu den Vertragstexten der früheren ZTV BEL-FÜ (ZTV-ING 8-2) und heutigen ZTV-ING Teil 6 Abschnitt 7 aus und erläutert die „Zusätzlichen Technischen Vertragsbedingungen und Richtlinien für Ingenieurbauten, Teil 6: Bauwerksausstattung, Abschnitt 7: Fahrbahnübergänge aus Asphalt“. Dabei geht es insbesondere um Fugen von Ingenieurbauwerken des Verkehrswegebaus, die quer oder in einem bestimmten Winkel zur Fahrbahn verlaufen und befahren werden. Diese Fugen müssen deshalb einerseits in fahrtechnischem Sinne verschlossen werden, damit die Fahrzeuge den Spalt störungsfrei und verkehrssicher überqueren können. Andererseits ist ein Fugenverschluss zum Schutz des Tragwerks vor Feuchte- oder Schadstoffbeanspruchung (Korrosionsgefahr) erforderlich. Je nach Größe des Fugenspaltes und der auftretenden Bewegungen müssen die Fugenfüllungen unterschiedlich ausgebildet werden, um die überquerenden Lasten sicher in das Tragwerk abzuleiten. Bauteile oder Konstruktionen, die diese verkehrstechnische Aufgabe übernehmen, werden allgemein als Fahrbahnübergänge bezeichnet. Die H ZTV-ING 6-7 ersetzen die „Hinweise und Erläuterungen zu den Zusätzlichen Technischen Vertragsbedingungen und Richtlinien für die Herstellung von Fahrbahnübergängen aus Asphalt in Belägen auf Brücken und anderen Ingenieurbauwerken aus Beton“, Ausgabe 2001. Die Überarbeitung der „Hinweise und Erläuterungen“ wurde aufgrund der Überarbeitung der ZTV-ING 6-7 erforderlich. Außerdem wurden in den Hinweisen neue Entwicklungen in den Bereichen der Fahrbahnübergänge aus Asphalt mit größeren Einbaubreiten und dehnungsverteilenden Einbauten, der Belagsdehnfugen sowie des Oberflächenabschlusses mit GFK-Platten berücksichtigt. KW - Brückenbeläge KW - Asphaltbauweise KW - Dehnfugen PY - 2022 SN - 978-3-86446-329-7 VL - 780/4 SP - 1 EP - 35 PB - FGSV Verlag GmbH CY - Köln AN - OPUS4-54858 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Pirskawetz, Stephan T1 - Digital acoustic twin for prestressed concrete structures N2 - In den 1950er Jahren setzte sich die Spannbetonbauweise für Brücken mit größeren Spannweiten durch. Heute existieren im deutschen Bundesfernstraßennetz ca. 21.000 Spannbetonbrücken. Die mangelnde Erfahrung in der Anfangszeit dieser Bauweise stellt uns heute vor Probleme hinsichtlich einer Kombination aus Korrosion und Ermüdung der Spannglieder. Hauptursachen sind Spannungsrisskorrosion, deutlich gewachsene Verkehrslasten sowie ungenügende Annahmen zu Temperaturlasten. Insbesondere Spanndrahtbrüche infolge Spannungsrisskorrosion können zu einem Strukturversagen ohne Ankündigung führen. Spannstähle mit einer starken Gefährdung für Spannungsrisskorrosion wurden in der Bundesrepublik bis 1965, in der ehemaligen DDR bis Ende der 1980er Jahre verbaut. Um katastrophale Schadensfälle zu verhindern, müssen Bauwerke unter Verdacht auf Spannungsrisskorrosion in Kombination mit unzureichendem Ankündigungsverhalten überwacht werden. Derzeit ist die Schallemissionsanalyse die einzige zuverlässige und ökonomisch vertretbare Überwachungsmethode. Damit kann der sichere Betrieb der Bauwerke über die verbleibende Nutzungsdauer gewährleistet werden. Die DGZfP-Richtlinie SE05 “Detektion von Spanndrahtbrüchen mit Schallemissionsanalyse” beschreibt detailliert Planung, Installation und Betrieb solcher Monitoringsysteme. Im Projekt SimAS “Digitaler Zwilling zur Simulation der Ausbreitung akustischer Wellen in Spannbetonelementen” werden die Grundlagen für eine Optimierung der Monitoringsysteme auf Basis der Schallemissionsanalyse gelegt. Eine akustische Simulation der Struktur und deren Fusion mit Messdaten unterstützt sowohl die vorbereitenden akustischen Analysen der Brücken als auch die Planung der Monitoringsysteme und die Drahtbrucherkennung. T2 - SCHALL 25 – Schallemissionsanalyse und Zustandsüberwachung mit geführten Wellen CY - Dresden, Germany DA - 27.03.2025 KW - Acoustic Emission KW - Spannbeton KW - Brücke KW - Digitaler akustischer Zwilling KW - Schallausbreitung KW - Schallemissionsanalyse PY - 2025 AN - OPUS4-62835 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Fiedler, Max A1 - Pirskawetz, Stephan A1 - Kaplan, Felix A1 - Holst, Ralph A1 - Saloga, Katrin A1 - Schmidt, Sebastian A1 - Sodeikat, Christian T1 - Detektion von Spanndrahtbrüchen mit Schallemissionsanalyse T1 - Detection of Wire Breaks using Acoustic Emission Analysis - The New Guideline SE 05 of the German Society for Non- Destructive Testing (DGZfP) N2 - AbstractSpannungsrisskorrosion stellt Brückenbetreiber vor immense Herausforderungen, da sie zu gravierenden Schäden an den Spanngliedern führen kann und gleichzeitig die Methoden zur frühzeitigen Schadenserkennung und Tragfähigkeitskontrolle stark eingeschränkt sind. In diesem Kontext hat sich die Schallemissionsanalyse (SEA) zur Detektion von Spanndrahtbrüchen als bedeutsame Methode etabliert. Diese Technologie bietet einzigartige Vorteile und kann einen wichtigen Beitrag zur Sicherstellung des Weiterbetriebs gefährdeter Bauwerke liefern. Gleichzeitig erfordert die Anwendung der SEA tiefgehende spezialisierte Fachkenntnisse. Mit der zunehmenden Verbreitung und dem steigenden Interesse an dieser Methode ist auch der Bedarf an standardisierten Prozessen und Qualitätskontrollen gewachsen. Diesen Bedarf hat der Fachausschuss Schallemissionsprüfung der DGZfP erkannt und die Richtlinie  SE 05 entwickelt. Diese Richtlinie setzt klare Standards und bietet umfassende Anleitung für die Implementierung und Anwendung der Schallemissionsanalyse zur Detektion von Spanndrahtbrüchen. N2 - Stress corrosion cracking confronts bridge operators with immense challenges, as it can lead to severe damage to the tendons while the methods for early damage detection and load-bearing capacity control are highly limited. In this context, Acoustic Emission Analysis (AEA) has established itself as an important method for detecting wire breaks. This technology offers unique advantages and can make a vital contribution to ensuring the continued operation of endangered structures. However, the application of AEA requires deep specialized expertise. With the increasing adoption and growing interest in this method, the need for standardized processes and quality controls has also grown. The DGZfP’s Acoustic Emission Testing Committee recognized this need and developed Guideline SE 05. This guideline sets clear standards and provides comprehensive guidance for the implementation and application of Acoustic Emission Analysis for detecting wire breaks. KW - Brücke KW - Spannungsrisskorrosion KW - Monitoring KW - Schallemission KW - Spanndrahtbrucherkennung KW - Schadensdetektion KW - Richtlinie SE 05 KW - DGZfP PY - 2025 DO - https://doi.org/10.1002/best.202400098 SN - 1437-1006 VL - 119 IS - 2 SP - 150 EP - 164 PB - Ernst & Sohn GmbH CY - Berlin AN - OPUS4-62753 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Recknagel, Christoph A1 - Eilers, Manfred A1 - Hoppe, Johannes A1 - Cetinkaya, Reha A1 - Machill, Nicole A1 - Weitz, Dennis A1 - Zscherpe, Oliver A1 - Sikinger, Thomas A1 - Loher, erich A1 - Oelerich, Martin A1 - Schäfer, Volker A1 - Schäfer, Thorsten A1 - Uslu, Cenk A1 - Virnau, Lucas A1 - Dudenhöfer, Bernd A1 - Rückert, Phillip A1 - Alte-Teigeler, Ralf A1 - Rau, Richard T1 - Merkblatt für die Herstellung von Abdichtungssystemen aus hohlraumreichen Asphalttraggerüsten mit nachträglicher Verfüllung (HANV) für Ingenieurbauten aus Beton N2 - Konventionelle Regelbauweisen für die Ausbildung von Abdichtungssystemen auf Brücken- und anderen Ingenieurbauwerken aus Beton machen signifikante material- und systembedingte Einbau- und Sperrzeiten erforderlich. Das innovative Abdichtungssystem „Hohlraumreiches Asphalttraggerüst mit nachträglicher Verfüllung“ (kurz: HANV) bietet eine deutliche Zeitersparnis von Ausführung bis Verkehrsfreigabe. Gleichzeitig zeichnet sich diese Bauweise mit einer hohen Deformationsbeständigkeit gegenüber Schwerlastverkehr aus. Auf der Grundlage eines mittlerweile ausgeprägten Erfahrungshintergrundes wird mit Hilfe des aufgestellten Regelwerkes der Baupraxis eine qualitätssichere Ausführung mit gütegesicherter Funktionalität zur Verfügung gestellt. KW - Abdichtungssysteme KW - Verkehrs-Infrastrukutur KW - Ingenieurbauwerke aus Beton PY - 2025 SN - 978-3-86446-421-8 VL - 2025 IS - 1 SP - 3 EP - 40 PB - FGSV-Verlag CY - Wesselinger Straße 15-17 in 50999 Köln ET - 1. Auflage AN - OPUS4-62798 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Robens-Radermacher, Annika T1 - Model identification coupling Bayesian Inference with PGD reduced models with random field material parameters N2 - The main challenge using numerical models as digital twins in real applications is the calibration and validation of the model based on uncertain measurement data. Therefore, model updating approaches which are inverse optimization processes are applied. This requires a huge number of computations of the same numerical model with slightly different model parameters. For that reason, model updating becomes computationally very expensive for real applications. Model reduction, e.g. the proper generalized decomposition method, is a popular concept to decrease the computational effort of complex numerical simulations. Therefore, a reduced model of the structure of interest is derived and will be used as surrogate model in a Variational Bayesian procedure to create a very efficient digital twin of the structure. An efficient model updating approach by means of a PGD reduced model with random field material stiffness parameters is shown. The random field allows, to calibrate the model considering parameter changes over the spatial direction. These changes can be caused by local damages as well as by production. As an exemplary application a demonstrator bridge is used. Digital twins can reduce the costs for maintenance and inspections especially for the costly civil infrastructure with high requirements at their performance over the whole lifetime. Currently, the current state of the structure is determined by regular manual and visual inspections within constant intervals. However, the critical sections are often not directly accessible or impossible to be instrumented at all. In this case, model-based approaches where a digital twin is set up can improve the process. Based on this digital twin, a prognosis of the future performance of the structure, e.g. the failure probability, can be computed. The influences of the reduction degree, the mesh discretization as well as the correlation length in the PGD Bayesian approach are studied by means of the digital twin of a simple pre-stressed concrete two field bridge. T2 - Annual Meeting of the International Association of Applied Mathematics and Mechanics (GAMM) 2020@21 CY - Online meeting DA - 15.03.2021 KW - Digital twin supporting KW - Proper generalized decomposition PY - 2021 AN - OPUS4-52317 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Gebauer, D. A1 - Gutierrez, B. A1 - Marx, S. A1 - Maack, Stefan A1 - Küttenbaum, Stefan A1 - Pirskawetz, Stephan A1 - Breit, W. A1 - Mechtcherine, V. A1 - Grahl, K. A1 - Thiel, T. A1 - Schickert, M. A1 - Krüger, M. T1 - Interrelated data set from nondestructive and destructive material testing of concrete compressive strength specimens N2 - This data set contains three different data types obtained from concrete specimens. For each specimen, the rebound numbers, ultrasonic data (ultrasonic velocity, time of flight), and destructive concrete strength are given. Two kind of specimen geometries were tested: cubes and drilled cores. The files are labeled according to the specimen geometry as "cube" or "core" and the type of measurement data as "compressive_strength", "rn_R" and "rn_Q" for rebound numbers as well as "us" for ultrasonic data. The ultrasonic data were generated by six independent laboratories, the rebound numbers by five independent laboratories and the destructive tests by one laboratory. The designation of each specimen establishes the relationship between the different data types. KW - Non-destructive testing KW - Rebound number KW - Ultrasonic pulse velocity KW - Compressive concrete strength KW - Interlaboratory comparison PY - 2023 DO - https://doi.org/10.7910/DVN/AFCITK PB - Harvard College CY - Cambridge, MA, USA AN - OPUS4-57499 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Diercks, Philipp T1 - Reduced order Approximations of fine scale edge basis functions within a variational multiscale approach N2 - In analyzing large scale structures, it is necessary to take into account the material heterogeneity for accurate failure prediction. However, this greatly increases the degrees of freedom in the numerical method thus making it infeasible. Moreover, in applications where scale separation as the basis of classical homogenization schemes does not hold, the influence of the fine scale on the coarse scale has to be modelled directly. This work aims to develop an efficient methodology to model heterogeneous structures combining the variational multiscale method and model order reduction techniques. Superposition-based methods assume a split of the solution field into coarse and fine scale contributions. In deriving practical methods, some form of localization is necessary to eliminate the fine-scale part from the coarse-scale equation. Hund and Ramm [2] discussed different locality constraints and in particular zero jump conditions enforced by a Lagrange-type method leading to a coupled solution scheme. In this contribution, a combination of the variational multiscale method and model order reduction techniques is applied to model the influence of the fine scale on the coarse scale directly. First, possible coarse and fine scale solutions are exploited for a representative volume element (RVE), specific to the material of interest, to construct local approximation spaces. For the local fine scale spaces different choices are presented, which ensure continuity between adjacent coarse grid elements. Therefore,the resulting global system takes into account, the effect of the fine scale on the coarse scale, is sparse and has much lower dimensions compared to the full system in the direct numerical simulation. The authors gratefully acknowledge financial support by the German Research Foundation (DFG), project number 394350870. This result is part of a project that has received funding from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation programme (Grant agreement No. 818473). T2 - COMPLAS 2021 CY - Berlin, Germany DA - 07.09.2021 KW - Multiscale methods KW - Variational multiscale method KW - Model order reduction PY - 2021 AN - OPUS4-53289 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Unger, Jörg F. T1 - Uncertainty Quantification and Model Extension for Digital Twins through Model Bias Identification N2 - Using digital twins requires precise digital models that accurately reflect their physical counterparts. Ensuring their trustworthiness and enabling informed decision making requires a robust approach to Uncertainty Quantification (UQ). A suitable model update scheme is crucial to preserve the quality and robustness of simulation-based digital twins. Model bias resulting from discrepancies between computational models and real systems pose a significant challenge in achieving this goal. Two alternative methods for identifying additive model discrepancies are investigated in comparison with the classical Bayesian inference framework - a modularized version of Kennedy and O'Hagan's approach [1] and another based on orthogonal Gaussian processes [2]. Furthermore, embedded bias approaches based on hierarchical Bayesian methods are used to incorporate the bias on the level of the parameters [3]. This improves the predictive quality of quantities that are not directly measured and allows for more accurate estimates of the uncertainty bounds. The approaches are demonstrated for predicting the complete temperature distribution and compensating for thermal deformations in a real structural problem, using data from a limited number of sensors. T2 - FrontUQ 2024 ​ CY - Braunschweig, Germany DA - 24.09.2024 KW - Model bias KW - Uncertainty quantification KW - Digital twin KW - Model updatin PY - 2024 AN - OPUS4-62106 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Pirskawetz, Stephan T1 - Acoustic emission for monitoring of fatigue damage in concrete elements of wind turbine towers N2 - Wind energy has become an important player in the energy transition in Germany. Towers of onshore wind turbines are often designed as hybrid structures: the lower part is made of prestressed concrete whereas the upper part is made of steel tubes. The tall structures are permanently subjected to cyclic loads. A research project of BAM as part of the joint project WinConFat - Structure focusses on the development of techniques to monitor fatigue damage evolution in the concrete part. Results of a previous project show that a combination of ultrasonic and acoustic emission testing can give an indication for critical conditions near the end of the fatigue life of the concrete. In the ongoing project acoustic emission sensors have been installed at the base and at the transition piece between concrete and steel of a hybrid wind turbine tower. Beside of acoustic emission measurement the sensor spacing allows for measuring the concrete ultrasonic velocity along the circumference in both levels. Additional measurements like strain, temperature, inclination, or acceleration allow for comparison of environmental loads and change of acoustic properties of the concrete. The paper focusses on first acoustic measurements recorded since December 2023 in comparison to operating data of the wind turbine. T2 - 36th Conference of the European Working Group on Acoustic Emission CY - Potsdam, Germany DA - 18.09.2024 KW - Concrete fatigue monitoring KW - Acoustic emission KW - Ultrasound KW - Hybrid wind turbine tower PY - 2024 AN - OPUS4-61566 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Unger, Jörg F. A1 - Robens-Radermacher, Annika A1 - Tamsen, Erik T1 - Data provenance - from experimental data to trustworthy simulation models and standards N2 - FAIR (findable, accessible, interoperable and reusable) data usage is one of the main principals that many of the research and funding organizations include in their strategic plans, which means that following the main principals of FAIR data is required in many research projects. The definition of data being FAIR is very general. When implementing that for a specific application or project or even setting a standardized procedure within a working group, a company or a research community, many challenges arise. In this contribution, an overview about our experience with different methods and tools is outlined. We begin with a motivation on potential use cases for the application of FAIR data with increasing complexity starting from a reproducible research paper over collaborative projects with multiple participants such as Round-Robin tests up to data-based models within standardization codes, applications in machine learning or parameter estimation of physics-based simulation models. In a second part, different options for structuring the data (including metadata schema) are discussed. The first one is the openBIS system, which is an open-source lab notebook and PostgreSQL based data management system. A second option is a semantic representation using RDF based on ontologies for the domain of interest. In a third section, requirements for workflow tools to automate data processing are discussed and their integration into reproducible data analysis is presented with an outlook on required information to be stored as metadata in the database. Finally, the presented procedures are exemplarily demonstrated for the calibration of a temperature dependent constitutive model for additively manufactured mortar. A metadata schema for a rheological measurement setup is derived and implemented in an openBIS database. After a short review of a potential numerical model predicting the structural build-up behavior, the automatic workflow to use the stored data for model parameter estimation is demonstrated. KW - FAIR data KW - Semantic web KW - Scientific workflows KW - Metadata KW - Reproducible data processing PY - 2023 DO - https://doi.org/10.1016/j.matpr.2023.08.081 SP - 1 EP - 10 PB - Elsevier AN - OPUS4-58215 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Weigel, Sandra T1 - Ein Ausblick: Alternative Bindemittel für bitumenhaltige Materialien N2 - Im Straßen- und Ingenieurbau sind neben dem Baustoff Beton auch bitumenhaltige Materialien in Flächenabdichtungen, Dehnfugenkonstruktionen und Asphaltbelägen von entscheidender Bedeutung. Die bestehende Erdölabhängigkeit dieser Materialien fordert jedoch ein dringendes Umdenken, wobei langfristig die Substitution des Bitumens durch nachhaltige, biobasierte Alternativmaterialien angestrebt werden sollte. Durch eine partielle Substitution wäre zudem bereits kurz- bis mittelfristig eine Reduzierung der Erdölabhängigkeit möglich, wobei sich z.B. Rückstände der Mikroalgenaufbereitung oder Lignin als Substitutionsprodukte eignen. T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM Green Intelligent Building CY - Berlin, Germany DA - 16.10.024 KW - Bitumen KW - Alternative Bindemittel KW - Lignin KW - Mikroalgenrückstände PY - 2024 AN - OPUS4-61737 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - RPRT A1 - Weise, Frank A1 - Fladt, Matthias A1 - Meyer, I. T1 - Bewertung der Innenhydrophobierung von Fahrbahndeckenbetonen als neuartige AKR-Vermeidungsstrategie T1 - Evaluation of internal water-repellent treatment of concrete pavements as a novel AAR preventive measure N2 - Zur Nutzbarmachung grenzwertig alkaliempfindlicher Gesteinskörnungen für Betonfahrbahndecken wurde basierend auf einer Literaturrecherche die Eignung von je einem Innenhydrophobierungsmittel auf der Basis eines Kalziumstearats (HM-A), eines Silan-Siloxan-Gemisches (HM-B) sowie eines der Vertraulichkeit unterliegenden Wirkstoffs (HM-C) für die neuartige AKR-Vermeidungsstrategie untersucht. Die Basis für die Eignungsuntersuchungen bildeten die Rezepturen im ARS 04/2013 für den OB (D>8)/UB sowie für den OB 0/8. Zur Herausarbeitung des Einflusses des Hydrophobierungsmittels auf die schädigende AKR fand in der groben Kornfraktionen ein alkaliempfindlicher Grauwackesplitt Anwendung. Aufgrund der unterschiedlichen Wechselwirkung zwischen dem LP-Bildner und dem Hydrophobierungsmittel wurde seine Dosierung beim HM-A reduziert sowie beim HM-B geringfügig und beim HM-C um ein Vielfaches erhöht. Ausgehend von den ausgewählten Rezepturen mit den unterschiedlichen Hydrophobierungsmitteln wurden bei den Untersuchungen u.a. folgende Erkenntnisse gewonnen: • Nachweis der Funktionalität aller drei Hydrophobierungsmittel im Festbeton durch signifikant reduzierte kapillare Aufnahme der Prüflösung. • Verschlechterung der mechanischen Eigenschaften und des Frost-Tausalzwiderstands des OB (D>8)/UB bei Zugabe aller Hydrophobierungsmittel. • Verzicht auf den Einsatz des HM-A im OB (D>8)/UB aufgrund drastischer Verschlechterung der Verarbeitbarkeit des Frischbetons und hohem Festigkeitsverlust. • Verzicht auf den Einsatz des HM-B im OB (D>8)/UB aufgrund der Überschreitung des Dehnungsgrenzwerts nach dem 9. bzw. 10. Zyklus (mit bzw. ohne zyklischer Vorschädigung) und der einhergehenden starken Abwitterung bei der KWL mit NaCl-Lösung. • Nachweis nachhaltiger Verminderung schädigender AKR in beiden Betonarten mit HM-C in Klimawechsellagerung und 60°C-Betonversuch mit externer Alkalizufuhr, allerdings zu Lasten der mechanischen Eigenschaften und des Frost-Tausalz-Widerstands. Fazit: Bei geeigneter Wirkstoffauswahl hat die Innenhydrophobierung das Potenzial für die Nutzbarmachung grenzwertiger Gesteinskörnung. Ihre Überführung in die Praxis erfordert jedoch eine weitere ganzheitliche Optimierung der Baustoffperformance. Das schließt auch die Verifizierung gezielter betontechnologischer Maßnahmen zur Verminderung der Verschlechterung der mechanischen Eigenschaften und des Frost-Tausalz-Widerstandes ein. N2 - In order to enable utilization of borderline-acceptable alkali-sensitive aggregates for concrete road pavements, the applicability of an internal hydrophobic treatment for a novel alkali-aggregate reaction (AAR) preventive measure was investigated. On the basis of a literature review, a calcium stearate (HM-A), a silane-siloxane emulsion (HM-B) and an active agent (HM-C), which is subject to confidentiality, were investigated. The mix designs from ARS 04/2013 for OB (D>8)/UB as well as for OB 0/8 formed the basis for the qualification tests. In order to shed light on the influence of the hydrophobic agent on the damaging AAR, alkali-sensitive greywacke chippings were used as the coarse grain aggregates. Due to the varying interaction between the air-entraining agent and the hydrophobic agent, the hydro-phobic agent dosage was reduced for HM-A, increased slightly for HM-B and increased many times over for HM-C. Based on the selected concrete mixes with the different hydrophobic agents the following findings were obtained: • Proof of the functionality of all three hydrophobic agents in hardened concrete by significantly reduced capillary absorption of the test solution. • Deterioration of the mechanical properties and the resistance to freeze-thaw with de-icing salt of the OB (D>8)/UB through the addition of all hydropho-bic agents. • The use of HM-A in OB (D>8)/UB should be avoided because of drastic deterioration of the workability of the fresh concrete and significant loss of strength. • The use of HM-B in OB (D>8)/UB was abandoned due to the exceeding of the expansion limit value from the 9th or 10th cycle onwards (with or without cyclical pre-damage) and the accompanying severe scaling during the cyclic climate storage test (CCST) with NaCl solution. • Proof of sustainable reduction of harmful AAR in both types of concrete with HM-C in CCST and 60°C concrete prism tests with external alkali supply. The disadvantage is deterioration of the mechanical properties and the resistance to freeze-thaw with de-icing salt. Conclusion: With a suitable selection of hydrophobic agent, internal waterrepellent treatment has the potential to enable utilization of borderline-acceptable alkali-sensitive aggregates. However, its transfer into practice re-quires a further holistic optimization of the building material performance. This includes the verification of specific concretetechnological measures to improve both, the mechanical properties and the resistance to freeze-thaw with de-icing salt. KW - Tausalzeintrag KW - Betonfahrbahndecke KW - Alkali-Kieselsäure-Reaktion PY - 2022 SN - 978-3-95606-643-6 SN - 0344-0788 VL - 1141 SP - 1 EP - 281 PB - Fachverlag NW in der Carl Ed. Schünemann KG CY - Bremen AN - OPUS4-54757 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Robens-Radermacher, Annika A1 - Unger, Jörg F. T1 - Efficient reliability analysis coupling importance sampling using adaptive subset simulation and PGD model reduction N2 - One of the most important goals in civil engineering is to guaranty the safety of constructions. National standards prescribe a required failure probability in the order of 10−6 (e.g. DIN EN 199:2010-12). The estimation of these failure probabilities is the key point of structural reliability analysis. Generally, it is not possible to compute the failure probability analytically. Therefore, simulation-based methods as well as methods based on surrogate modeling or response surface methods have been developed. Nevertheless, these methods still require a few thousand evaluations of the structure, usually with finite element (FE) simulations, making reliability analysis computationally expensive for relevant applications. The aim of this contribution is to increase the efficiency of structural reliability analysis by using the advantages of model reduction techniques. Model reduction is a popular concept to decrease the computational effort of complex numerical simulations while maintaining a reasonable accuracy. Coupling a reduced model with an efficient variance reducing sampling algorithm significantly reduces the computational cost of the reliability analysis without a relevant loss of accuracy. T2 - GAMM - Gesellschaft für Angewandte Mathematik und Mechanik e.V. CY - Wien, Austria DA - 18.02.2019 KW - PGD model reduction KW - Numerical models KW - FE modelling PY - 2019 DO - https://doi.org/10.1002/pamm.201900169 VL - 19 IS - 1 SP - 1 EP - 2 PB - Wiley- VCH Verlag GmbH CY - Weinheim AN - OPUS4-49786 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schneider, Ronald T1 - Integrating vibration monitoring into risk-based inspection and maintenance planning for deteriorating structural systems N2 - A reliability and risk-based framework for integrating vibration monitoring data in the planning of inspection and maintenance of deteriorating structural systems is discussed and demonstrated in a numerical example. T2 - Wind Energy Science Conference (WESC 2021) CY - Online Meeting DA - 25.05.2021 KW - Deterioration KW - Structural systems KW - Inspection KW - Vibration monitoring KW - Maintenance PY - 2021 AN - OPUS4-52766 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - THES A1 - Titscher, Thomas T1 - Efficient computational mesoscale modeling of concrete under cyclic loading N2 - Concrete is a complex material and can be modeled on various spatial and temporal scales. While simulations on coarse scales are practical for engineering applications, a deeper understanding of the material is gained on finer scales. This is at the cost of an increased numerical effort that can be reduced by the three methods developed and used in this work, each corresponding to one publication. The coarse spatial scale is related to fully homogenized models. The material is described in a phenomenological approach and the numerous parameters sometimes lack a physical meaning. Resolving the three-phase mesoscopic structure consisting of aggregates, the mortar matrix and the interfaces between them allow to describe similar effects with simpler models. KW - Concrete KW - Fatigue failure KW - Damage KW - Mesoscale PY - 2019 VL - 9 SP - 1 EP - 52 PB - UPC - Universitat Politecnica de Catalunya Barcelona CY - Barcelona AN - OPUS4-50362 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Unger, Jörg F. T1 - Bayesian model updating for predictive digital twins under model form uncertainty N2 - Simulation models are an essential tool to support decision making in civil engineering. Since the structures are often unique, full scale experimental validations are very costly or even impossible and the consequences of failure are severe, the simulation models have to be reliable and should provide results with sufficient safety margins, often resulting in very conservative designs. For innovative approaches such as 3D concrete printing, these models are even more important - supporting not only an a priori design optimization, but provide the option for a real-time process control or a quality assessment in a post-processing by evaluating the impact of discrepancies between the as-designed and as-built structures on quantities of interest. The simulation models are typically parameterized, and with the inclusion of noisy measurement data and prior knowledge of model parameters, Bayesian methods allow for the estimation of posterior parameter distributions. However, engineers are often interested in quantities of interest (QoIs) that are either not measured at the location of interest or cannot be measured directly, such as maximum stresses, failure probabilities or remaining useful life. Propagating posterior parameter distributions to these QoIs generally underestimates their uncertainty, especially when dealing with large datasets which is typical for digital twins with a constant data flow. One of the reasons is the fact that model form uncertainty is usually neglected. However, for complex structures involving interacting physical processes, model form uncertainty due to modeling assumptions and simplifications is unavoidable to ensure computational tractability of the simulation models. As a consequence, it is required to incorporate these additional uncertainties in the computational approach and model updating procedure. This work presents embedded Bayesian methods that integrate model form uncertainty into the parameter space by transforming the deterministic model into a stochastic one [1]. The propagation of these parameter distributions through the model is achieved using polynomial chaos expansion techniques. Additionally, the likelihood is redefined using Approximate Bayesian Computation (ABC) methods. The proposed methods are applied to several structural engineering case studies, ranging from model calibration for 3D concrete printing based on laboratory tests to the digital twin of the Nibelungen bridge in Worms, Germany. T2 - Digital Twins in Engineering & Artificial Intelligence and Computational Methods in Applied Science, DTE - AICOMAS 2025 CY - Paris, France DA - 17.02.2025 KW - Bayesian inference KW - Model updating KW - Parameter estimation KW - Model form uncertainty PY - 2025 AN - OPUS4-62748 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bäßler, Ralph T1 - ISO 27913 - Example For Successful Standardization Activities In The Field Of CCUS N2 - Since 2016 ISO Technical Committee (TC) 265 is working on standardization the whole CCS-process chain. Around 30 countries are working together to provide international guidelines. As ISO 27913 was the first standard finished within these activities it is already in the stage of first revision. The objective of ISO 27913 is “to provide specific requirements and recommendations on certain aspects of safe and reliable design, construction and operation of pipelines intended for the large-scale transportation of CO2 that are not already covered in existing pipeline standards such as ISO 13623, ASME B31.8, EN 1594, AS 2885 or other standards. Existing pipeline standards cover many of the issues related to the design and construction of CO2 pipelines; however, there are some CO2 specific issues that are not adequately covered in these standards. The purpose of this document is to cover these issues consistently. Hence, this document is not a standalone standard, but is written to be a supplement to other existing pipeline standards for natural gas or liquids for both onshore and offshore pipelines.” This contribution shall provide information on the content, the current stage of the revision process, encourage to contribute to this standard and make listeners aware to consider the influence of ISO standard on documents currently in draft. T2 - AMPP's Annual Conference + Expo 2024 CY - New Orleans, LA, USA DA - 02.03.2024 KW - Corrosion resistant materials KW - Carbon dioxide KW - Corrosion prevention KW - Standardization KW - CCUS KW - CCS KW - CCU PY - 2024 AN - OPUS4-59736 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Thiele, Marc A1 - Pirskawetz, Stephan T1 - Analysis of damage evolution in concrete under fatigue loading by acoustic emission and ultrasonic testing N2 - The fatigue process of concrete under compressive cyclic loading is still not completely explored. The corresponding damage processes within the material structure are especially not entirely investigated. The application of acoustic measurement methods enables a better insight into the processes of the fatigue in concrete. Normal strength concrete was investigated under compressive cyclic loading with regard to the fatigue process by using acoustic methods in combination with other nondestructive measurement methods. Acoustic emission and ultrasonic signal measurements were applied together with measurements of strains, elastic modulus, and static strength. It was possible to determine the anisotropic character of the fatigue damage caused by uniaxial loading based on the ultrasonic measurements. Furthermore, it was observed that the fatigue damage seems to consist not exclusively of load parallel oriented crack structures. Rather, crack structures perpendicular to the load as well as local compacting are likely components of the fatigue damage. Additionally, the ultrasonic velocity appears to be a good indicator for fatigue damage beside the elastic modulus. It can be concluded that acoustic methods allow an observation of the fatigue process in concrete and a better understanding, especially in combination with further measurement methods. KW - Concrete KW - Fatigue KW - Damage evolution KW - Ultrasonic testing KW - Acoustic emission PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-541891 DO - https://doi.org/10.3390/ma15010341 SN - 1996-1944 VL - 15 IS - 1 SP - 341 EP - 355 PB - MDPI CY - Basel AN - OPUS4-54189 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Geburtig, Anja A1 - Wachtendorf, Volker A1 - Falkenhagen, Jana T1 - Combined impact of UV radiation and nitric acid on high‐density polyethylene containers as a laboratory test N2 - In a laboratory test, transparent high‐density polyethylene (HDPE) jerrycans have been exposed to both UV radiation and 55 wt‐% nitric acid solution at (41 ± 2)°C, for up to 20 days. For comparison, UV radiant exposure (21 days) and nitric acid exposure (up to 6 weeks) were performed separately, at nearly equal temperatures. The damages are compared with FTIR spectroscopy in ATR and HT‐gel permeation chromatography(GPC) on a molecular level and with hydraulic internal pressure testing as a component test. For the used jerrycans, relevant oxidation can only be found after the combined exposure. This is caused by the decomposition of nitric acid into nitrous gases by UV radiation, which is also observed at lower concentrations (28 wt‐%). After 6 days of laboratory exposure, this is rated as critical, which corresponds to about 1/10 year in Central Europe, according to the UV radiant exposure. The gradual increase in oxidative damage shows the reproducibility of the test. KW - Molecular mass distribution KW - High-density polyethylene KW - Nitric acid KW - UV radiation PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-550141 DO - https://doi.org/10.1002/pts.2673 SN - 0894-3214 SP - 1 EP - 7 PB - John Wiley & Sons Ltd AN - OPUS4-55014 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Burkert, Andreas T1 - Innovation und Sicherheit durch Einsatz von Duplexstählen in Straßentunneln N2 - Es werden die Ergebnisse eines mehrjährigen Forschungsvorhabens der BAM in Zusammenarbeit mit Straßenbauverwaltungen der Länder und Industriebeteiligten zur betriebstechnischen Ausrüstung von Straßentunneln präsentiert. Schwerpunkte waren die Bestimmung der Korrosivität der Atmosphäre von 3 ausgewählten Straßentunneln, die Analyse korrosionsrelevanter Ablagerungen und von Klimadaten. Die Auswirkungen dieser Einflussgrößen auf die Dauerhaftigkeit von Konstruktionen aus nichtrostenden Stählen wurde ermittelt und in Abhängigkeit verschiedener Einflussparameter dargestellt. Die Ergebnisse der systematischen Untersuchungen an Prüfköpern decken sich mit Beobachtungen an realen Bauteilen. Spaltbehaftete Konstruktionen aus Werkstoffen der CRC III führen demnach in Zeiträumen zwischen 10 und 15 Jahren zu Korrosionserscheinungen, welche die technische Sicherheit beeinträchtigen können und die erwartete Dauerhaftigkeit nicht erfüllen. Die Folge sind zusätzliche Sperrungen und ein vorzeitig notwendiger Unterhaltsaufwand, die erhebliche Kosten verursachen. Im Ergebnis ist eine Überarbeitung des aktuellen Regelwerkes erforderlich, um die angestrebte Dauerhaftigkeit von 30 Jahren zu gewährleisten. T2 - Sitzung ISER Marketingausschuss CY - Dusseldorf, Germany DA - 24.04.2024 KW - Korrosion KW - Straßentunnel KW - Dauerhaftigkeit KW - Nichtrostender Stahl PY - 2024 AN - OPUS4-59955 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - von Werder, Julia T1 - Curtain Walls with Biofilms for Improving the City Climate N2 - Building envelopes & natural rock surfaces represent the frontier between solid material surfaces, biosphere and the atmospheric environment – and are subject to permanent change in structure and chemistry. These surfaces are a natural habitat of subaerial rock biofilms (SAB) that are an important stage of primary succession. As their metabolic processes have a great impact on the composition of the near-surface layers of the earth biofilms on natural and manmade hard substrates are a research focus of geomicrobiology. In technical systems immobilized algae biofilms are already used successfully for wastewater cleaning. Algae can eliminate bacteria from the water and at the same time increase the oxygen concentration and the pH value in the water through photosynthesis, which again allows phosphate elimination to take place. Nitrificants contained in the algae biofilm convert ammonium to nitrite and nitrate. Mineral claddings for building facades could be engineered to sustain either natural or previously established carefully selected algae-dominated biofilms and this way help to clean the air. For a targeted engineering of the mineral substrates and the biofilms attached to them basic knowledge is however missing. By systematic research in an interdisciplinary team of microbiologists and building material scientists the following questions shall be clarified • How can a curated biofilm be stabilized on the surface and designed to be durable without compromising the substrate • What exactly do the biofilms need in terms of moisture in their respective growth stages? Or how long water must be available in what form and quantity to enable growth. • What is the influence of the substrate on the availability and quality of the (rain) water (water quality, leaching of substances (alkalis) from the building materials, leaching of aerosol components, surface tension, suction tension, thickness of the water molecule layers adsorbed in the pore spaces....) There are several research groups working on bioreceptive building materials which emphasizes the general interest in the topic. The idea of speeding-up the process by the targeted establishment of biofilms on building façade panels is a unique approach that has so far only been researched at BAM. Architects are very interested in biofilm facades as a new co-designing method of humans and nature reflecting the changing awareness for the loss of biodiversity in cities. If the biofilms need irrigation the evaporative cooling would reduce the urban heat island effect. T2 - Preparatory Workshop SPP 2451: Engineered Living Materials with Adaptive Functions CY - Saarbrücken, Germany DA - 10.07.2023 KW - Engineered living materials KW - Adaptive functions KW - Bioreceptivity KW - Biofilm KW - Concrete PY - 2023 UR - https://spp2451.de/event/preparatory-workshop/ AN - OPUS4-58965 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - von Werder, Julia T1 - Biorezeptiver Beton: Interdisziplinäre Forschung an der BAM N2 - Inhalt des Vortrags: Forschungsidee und Zielstellung, Forschungsstruktur, Veränderung, Wasserverfügbarkeit, Wasserrückhaltevermögen, pH-Wert, Speziesauswahl, Applikation, Monitoring von Bewuchs T2 - BDA Galerie, Ausstellung: wechselStoffwechsel, Galeriegespräch Nr. 3 CY - Berlin, Germany DA - 06.06.2023 KW - Biorezeptivität KW - Beton KW - Biofilm KW - Funktionalisierung KW - Fassade PY - 2023 UR - https://www.bda-berlin.de/events/wechsel-stoff-wechsel-gespraech-3/ AN - OPUS4-58961 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Burkert, Andreas T1 - Korrosionsprüfung N2 - Der Vortrag gibt einen Überblick über gängige Korrosionsversuche. Die wesentlichen Unterschiede zwischen Prüf- und Untersuchungsverfahren, deren jeweilige Zielstellung, Aussagefähigkeit und Grenzen werden aufgezeigt. Es werden ausgewählte Auslagerungsversuche, Kammerprüfungen sowie elektrochemische Messmethoden zur Bestimmung der Korrosionsbeständigkeit vorgestellt. Anhand praktischer Beispiele werden ausgewählte Ergebnisse der einzelner Methoden vorgestellt und diskutiert. T2 - VDEh Seminar "Korrosionsverhalten nichtrostender Stähle in wässrigen Medien und bei atmosphärischer Beanspruchung* CY - Düsseldorf, Germany DA - 30.01.2024 KW - Korrosion KW - Korrosionsversuche KW - Nichtrostender Stahl PY - 2024 AN - OPUS4-59553 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - RPRT A1 - Weise, Frank A1 - Werner, D. A1 - Maier, Bärbel A1 - Wilsch, Gerd T1 - Schadenskategoriespezifische Bewertung von AKR-Prüfverfahren T1 - Evaluation of ASR testing methods in relation to specific damage categories N2 - Ausgehend von den verstärkt auftretenden AKR-Schäden an den vor 2005 hergestellten BAB-Abschnitten verfolgte das Forschungsvorhaben zwei Ziele. So sollte einerseits die Ursache für die mit der AKR-Schadensentwicklung einhergehende Dunkelfärbung der Oberfläche der Betonfahrbahndecke im Fugenbereich ermittelt werden. Andererseits galt es, ausgehend von der Zustands- und Schadenserfassung das AKR-Restschädigungspotenzial der Prüfkörper aus je drei ein- und zweischichtig ausgeführten, unterschiedlich stark AKR-geschädigten BAB-Abschnitten vergleichend zu bewerten. Folgende Ergebnisse wurden u. a. erzielt: 1. Dunkelfärbung Experimenteller Nachweis mit kombinierter insitu- Feuchtemessung mit Radar (integral) und NMR (tiefenaufgelöst), dass Dunkelfärbung der Oberfläche der Betonfahrbahndecke im Fugenbereich auf eine erhöhte Durchfeuchtung der Betonrandzone zurückzuführen ist; erfolgreiche Validierung der ZfP-Ergebnisse mit Darr-Wäge-Versuch. 2. Zustand beprobter BAB-Abschnitte und schadenskategoriespezifische Bewertung der AKR-Prüfverfahren: • Auffinden von Horizontalrissen im Bereich der Querscheinfuge bei allen AKR-geschädigten BAB-Abschnitten, • Ermittlung mittlerer Eindringtiefen bei Natrium von maximal 20 bis 45 mm und bei Chlorid von maximal 15 bis 60 mm im Entnahmezustand; keine Korrelation mit der AKR-Schadenskategorie des jeweiligen BAB-Abschnitts, • Nachweis gleichzeitig auftretender SEB bei allen AKR-geschädigten BAB-Abschnitten im Entnahmezustand, • keine signifikante Verminderung der Spaltzugfestigkeit durch die verstärkte AKR am Plattenrand, • Ermittlung eines erhöhten AKR-Restschädigungspotenzials bei vier der sechs beprobten BAB-Abschnitte primär mittels AKR-erformanceprüfungen, • Ermittlung höherer Dehnungen bei Performanceprüfungen aus Ober- und Unterbeton bestehenden Halbschalen, als an separat aus Ober- und Unterbeton gewonnenen Prismen, • Unauffälliges Verhalten nahezu aller bei der Performanceprüfung auffälligen Bestandsbetone im 40°C- und 60°C-Betonversuch; vermutete Ursache: mit LIBS nachgewiesene hohe und tiefreichende Auslaugung der Alkalien. N2 - Our research project had two aims in addressing the increased occurrence of ASR damage on German motorway sections built before 2005: firstly, to establish the cause of the darker discolouration around the joints of concrete road surface that occurs in conjunction with ASR damage. Secondly, based on the status and damage report, it aimed to comparatively evaluate the residual ASR damage potential of test samples from three federal motorway sections of one-layer and three of twolayer pavement, showing different levels of ASR damage. We obtained the following results (among others): 1. Dark discolouration Experimental evidence using non-destructive testing methods showing that dark discolouration of concrete road surfaces near joints is due to increased moisture in the concrete boundary zone: NDT findings successfully validated by weighing and drying test. 2. Condition of sampled motorway sections and evaluation of ASR test methods used: • discovery of horizontal cracks located near transverse contraction joint in all motorway sections with ASR damage, • determination of maximum mean penetration depth of sodium from 20 to 45 mm and of chloride from 15 to 60 mm in sample as extracted; no correlation with the ASR damage category of the relevant motorway section, • evidence of simultaneous occurrence of DEF on all ASR-damaged motorway sections in sample as extracted, • no significant reduction of splitting tensile strength due to increased ASR at slab edge, • increased ASR residual damage potential found on four of the six motorway sections tested primarily with ASR performance tests, • increased expansion found during performance tests on half shells consisting of upper and lower concrete compared to prisms taken separately from upper and lower concrete, • 40°C and 60°C concrete prism tests revealed no noticeable reactions in almost all existing concrete types that showed irregularities in the performance test. Suggested cause: high and deep levels of alkali leaching determined by LIBS. KW - NMR-Relaxometrie KW - Alkali-Kieselsäure-Reaktion KW - Betonfahrbahndecke KW - AKR-Betonversuche KW - Zerstörungsfreie Prüfung KW - Radar PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:hbz:opus-bast-24661 UR - https://bast.opus.hbz-nrw.de/frontdoor/index/index/docId/2466 SN - 978-3-95606-543-9 SN - 0943-9323 VL - S 145 SP - 1 EP - 60 PB - Fachverlag NW in der Carl Ed. Schünemann KG CY - Bremen AN - OPUS4-54748 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Lehmann, Jens T1 - Offshore Auslagerung von nichtrostenden Stahlcoupons N2 - Zur Erweiterung der Anwendungserfahrungen nichtrostender Stähle, insbesondere von Lean-Duplex-Stählen, unter maritimen Einsatzbedingungen, wurden Testracks auf der Umspannplattform OSS des Windparks Hohe See errichtet. Hier wurden neben Standardproben zur Korrosivitätsbestimmung nach ISO 9223 auch mehrere Serien nichtrostender Stahlgüten mit unterschiedlichen Oberflächen, Spaltausbildungen und Verarbeitungszuständen ausgelagert und nun nach 1-jähriger Bewitterungszeit bewertet. In diesem Beitrag werden Oberflächenzustände, Korrosionszustände und Lochtiefen dieser Probekörper gezeigt. T2 - 21. Tagung Korrosionsschutz in der maritimen Technik CY - Hamburg, Germany DA - 24.01.2024 KW - Korrosion KW - Offshore KW - Atmosphärische Korrosion KW - Nichtrostender Stahl KW - Edelstahl rostfrei PY - 2024 AN - OPUS4-59452 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Lehmann, Jens T1 - Demonstrationsexperimente N2 - Ergänzend zu den theoretischen Betrachtungen des Korrosionsverhaltens nichtrostender Stähle werden in diesem Vortrag Demonstrationsexperimente gezeigt. T2 - Seminar Korrosionsverhalten nichtrostender Stähle in wässrigen Medien und bei atmosphärischer Beanspruchung CY - Düsseldorf, Germany DA - 30.01.2024 KW - Korrosion KW - Experimente KW - Elektrochemie KW - Nichtrostender Stahl KW - Edelstahl rostfrei PY - 2024 AN - OPUS4-59455 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Babutzka, Martin A1 - Grabowski, Sven A1 - Sahrhage, H. A1 - Lampke, T. T1 - Electrochemical corrosion investigations on binary and ternary zinc alloy coatings using gel electrolytes N2 - Novel agar-based test electrolytes are used to perform electrochemical corrosion investigations on ZnFe and ZnNi binary as well as ZnFeMo ternary zinc coatings. The objectives of the electrochemical investigations include the characterization of the corrosion behavior, the description of the protective effect of the coatings as well as the investigation of the layer formation and degradation under artificial aging. ZnFe and ZnFeMo coatings are applied with varying iron content as well as an additional passivation layer, respectively, to study the effect on corrosion resistance. The results show that the protective effect of the coatings is not negatively influenced by different iron contents or the addition of molybdenum. Additional passivation of the ZnFe-containing coatings by means of a passivating agent leads to a significant improvement in the protective effect. Artificial aging leads to slight degradation of the additional passivation layer whereas coatings without post-treatment enhance their protective effect by the formation of corrosion product layers. KW - Binary zinc alloys KW - Ternary zinc alloys KW - Corrosion testing KW - Gel electrolytes KW - Corrosion PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-543013 DO - https://doi.org/10.1002/adem.202101336 SN - 1438-1656 SP - 1 EP - 14 PB - Wiley-VCH CY - Weinheim AN - OPUS4-54301 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Burkert, Andreas T1 - Korrosionsarten bei nichtrostenden Stählen N2 - Übersichtsvortrag zu Korrosionsarten, die bei nichtrostenden Stählen unter verschiedenen Einsatzbedingungen auftreten können. Die Grundlagen zur Pasivität und der örtlichen Störung der Passivität werden im Zusammenspiel komplexer Einflussfaktoren des Korrosionssystems herausgestellt. Die erarbeiteten theoretischen Grundlagen werden anhand praktischer Beispiel für alle relevanten Korrosionsarten vertieft. T2 - VDEh Seminar "Korrosionsverhalten nichtrostender Stähle in wässrigen Medien und bei atmosphärischer Beanspruchung* CY - Düsseldorf, Germany DA - 30.01.2024 KW - nichtrostender Stahl KW - Korrosionsverhalten KW - Passivität PY - 2024 AN - OPUS4-59549 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - RPRT A1 - Weise, Frank A1 - Oesch, T. A1 - Wilsch, Gerd A1 - Sigmund, S. A1 - Hünger, K.-J. A1 - Kositz, M. T1 - Analyse des gefügeabhängigen Löslichkeitsverhaltens potenziell AKR-empfindlicher Gesteinskörnungen T1 - Analysis of the microstructure depending solubility behavior of potential ASR sensitive aggregates N2 - Das gefügeabhängige Löslichkeitsverhalten wurde an folgenden vier Gesteinskörnungen unterschiedlicher Alkaliempfindlichkeitsklassen untersucht: • GK1 (EIII-S): quarzreicher Kies • GK2 (EIII-S): Grauwacke (Splitt) • GK3 (EI-S): Quarz-Feldspat-Porphyr (Splitt) • GK4 (EI-S): sandsteinreicher Kies DiePorenstrukturanalyse erfolgte sowohl an Einzelkörnern mittels vergleichender 3D-CT und BET- Untersuchungen als auch an Korngemengen der einzelnen Kornfraktionen (außer Fraktion 16/22 mm) über die Wasseraufnahme und mit BET. Für die Visualisierung und Quantifizierung der von außen zugänglichen Oberflächenanteile der Einzelkörner wurde ein Softwaretool entwickelt, erprobt und erfolgreich angewandt. Es gelang so u.a. den Nachweis zu erbringen, dass die gebrochenen Einzelkörner der Grauwacke und des Rhyoliths einen deutlich geringeren von außen zugänglichen Oberflächenanteil als die gleichartigen Gesteinskörner aus dem Kies besitzen. Aufgrund der limitierten Ortsauflösung der 3D-CT von 11 bis 16,5 μm wurde mit BET eine um drei Zehnerpotenzen höhere spezifische Oberfläche ermittelt. Zu den Porositätsuntersuchungen an den Korngemengen sei angemerkt, dass zum Teil gegenläufige Trends zwischen offener Porosität und spezifischer Oberfläche festgestellt wurden. Dieses ist beim Bezug des bei den Löseversuchen in 0,1 M KOH mit definierter NaCl-Zugabe aus der Gesteinskörnung gelösten SiO2 und Al2O3 von zentraler Bedeutung. Bei den Löseversuchen an den fraktionsspezifischen Korngemengen selbst zeigte sich, dass die stufenweise Erhöhung des NaCl-Gehalts von 0 auf 10 M.-% im Eluat eine erhöhte SiO2-Löslichkeit und eine verminderte Auslaugung von Al2O3 zur Folge hat. Auffallend war hierbei, dass die Al2O3-Löslichkeit bei GK4 ohne und mit geringer NaCl-Zugabe die mit Abstand höchsten Werte annimmt. Bei den zusätzlich durchgeführten Löseversuchen an den tomografierten Einzelkörnern in 1 M KOH-Lösung mit Zugabe von 1 M.-% NaCl zeigte sich, dass nur vereinzelt bei den untersuchten Gesteinsarten eine Korrelation zwischen dem SiO2- bzw. Al2O3-Gehalt im Eluat und der absoluten BET-Oberfläche nachweisbar ist. Dies ist vermutlich darauf zurückzuführen, dass neben der Oberfläche weitere Parameter (z.B. die mineralogische Zusammensetzung der Einzelkörner) das Löseverhalten maßgebend beeinflussen. Bei den parallel zu den Löseversuchen durchgeführten Betonversuchen nach dem ARS 04/2013 zeigte sich, dass die Alkaliempfindlichkeit der GK4 bei beiden Betonversuchen mit Alkalizufuhr unterschiedlich zu bewerten ist. So ist unabhängig von der vorgegebenen pessimalen Betonrezeptur des Fahrbahndeckenbetons ausschließlich bei der Klimawechsellagerung die GK4 als alkaliempfindlich einzustufen. Allerdings konnte der Befund der stark ausgeprägten AKR bei der GK4 mit der Dünnschliffmikroskopie nicht bestätigt werden. Analoges gilt für die Bewertung der Alkaliempfindlichkeit von GK2 mit den Betonversuchen nach der Alkalirichtlichtlinie des DAfStb. So ist auch hier die GK2 nicht im 60 °C-Betonversuch sondern ausschließlich im 40 °C-Betonversuch als alkaliempfindlich einzustufen. Dienach den verschiedenartigen Betonversuchen durchgeführten LIBS-Analysen am Vertikalschnitt der Prüfkörper zeigen, dass im Kernbereich nach dem 60 °C-Betonversuch mit 10 %iger NaCl-Lösung und nach der Klimawechsellagerung mit NaCl-Beaufschlagung annähernd gleich hohe Natrium- und Chloridgehalte vorgefunden werden. Wider Erwarten treten an den beaufschlagten Prüfflächen Abreicherungen von Natrium und Anreicherungen von Chlorid auf. Im 40°C- und 60 °C-Betonversuch wurde das Natrium bis in eine maximale Tiefe von ca. 30 mm bzw. 20 mm ausgelaugt. Die aufbauenden korrelativen Betrachtungen zwischen den Ergebnissen des 60°C Betonversuchs mit Alkalizufuhr und der Löseversuche an den fraktionsspezifischen Korngemengen in 1 M KOH-Lösung mit definierter NaCl-Zugabe sind durchaus vielversprechend. So zeigt sich beispielsweise beim Waschbeton, dass der fraktionsspezifisch gewichtete SiO2-Überschuss im Eluat nach 56 Tagen mit Zugabe von 0,5 M.-% NaCl ohne Bezug auf die BET-Oberfläche zur gleichen Einstufung der vier betrachteten Gesteinskörnungen wie bei den Dehnungen im 60 °C-Betonversuch mit 3 %-iger NaCl-Lösung führt. Außerdem korrelieren die im 60 °C-Betonversuch mit 10 %-iger NaCl-Lösung ermittelten Dehnungen mit dem gewichteten SiO2-Überschuss im Eluat bei Zugabe von 2 M.-% NaCl ohne Bezug auf die BET-Oberfläche. Ausschließlich bei den Betonversuchen nach der Alkali-Richtlinie erwies sich der Bezug des im Eluat ermittelten SiO2-Überschusses auf die BET-Oberfläche als zielführend. Aufgrund des Potenzials der Löseversuche mit NaCl-Zugabe für die Bewertung der Alkaliempfindlichkeit der Gesteinskörnung im Fahrbahndeckenbeton wird empfohlen, die vergleichenden Untersuchungen zwischen den Löseversuchen an Korngemischen der einzelnen Fraktionen und den Betonversuchen nach dem ARS 04/2013 mit einer möglichst hohen Anzahl an Gesteinskörnungen und einem präzisierten Untersuchungsumfang fortzuführen. N2 - The following four aggregates (GK) of varying grades of alkali sensitivity were examined for their microstructure-dependent solubility behavior: • GK1 (EIII-S) gravel with high quarz content • GK2 (EIII-S) greywacke (crushed stone) • GK3 (EI-S) quarz-feldspar-porphyry (crushed stone) • GK4 (EI-S) gravel with high sandstone content Pore structure analysis was carried out both on single grains using comparative 3D-CT and BET tests, and on grain samples of individual grain fractions (excluding the 16/22 mm fraction) using water absorption and BET. A software tool for visualizing and quantifying the externally accessible surfaces of single grains was developed, tested and successfully applied. This enabled us, among other things, to prove that single broken grains of greywacke and rhyolite have a much smaller externally accessible surface than grains of gravel of the same aggregate fraction. Due to the 3D-CT’s limited spatial resolution of 11 to 16.5 μm, BET was used to determine a two to three powers of ten higher specific surface. In relation to the porosity tests of the grain samples, it should be noted that in some cases, counterdirectional trends between open porosity and specific surface were determined. This is of central importance in relation to the SiO2 and Al2O3 dissolved from the aggregate in the solubility tests in 1 M KOH with defined addition of NaCl. The solubility tests on the grain samples of specific fractions showed that the gradual increase of the NaCl content in the eluate from 0 to 10 M.-% resulted in increased SiO2 solubility and reduced leaching of Al2O3. It was striking in this context that the solubility of Al2O3 in GK4 with no or little addition of NaCl gives by far the highest values. The additional solubility tests carried out on single grains, that were previously subjected to CT testing, in 1 M KOH solution with 1 M.-% added NaCl showed that in the types of aggregate examined, a correlation between the SiO2 and Al2O3 in eluate and the absolute BET surface is only occasionally demonstrable. This is probably due to the fact that solubility behavior is decisively influenced by other parameters in addition to the surface (e.g. by the mineralogical composition of individual grains). The concrete tests according to ARS 04/2013 carried out parallel to the solubility tests showed that GK4’s alkali sensitivity in both concrete tests with added alkali must be evaluated differently. For example, independent of the prescribed pessimal road surface concrete formula, GK4 can only be classified as alkali sensitive under cyclic storage. However petrographic microscopy could not confirm the findings of very marked ASR in GK4. The same applies to the evaluation of alkali sensitivity in GK2 with the concrete tests according to the German Committee for Structural Concrete (DAfStb)’s Alkali Guidelines. In this case too, GK2 should not be classified as alkali sensitive in 60 °C concrete testing, but only in 40 °C concrete testing. The LIBS analyses carried out on the vertical cross-section of the test specimens after the various concrete tests showed that almost equally high sodium and chloride levels were found in the core area after the 60 °C concrete prism test with 10 % NaCl solution and after cyclic storage with NaCl application. Contrary to expectations, the surfaces of samples after NaCl application showed a decrease in sodium and an increase in chloride. In the 40°C and 60°C concrete prism tests, sodium was depleted up to a maximum depth of approx. 30 mm and 20 mm respectively. Subsequent correlative observations between the findings of the 60°C concrete prism test with alkali application, and the solubility tests on the samples of specific grain fractions in 1 M KOH solution with defined NaCl addition, are very promising. In the case of exposed aggregate concrete, for example, the fraction-specific weighted excess SiO2 to in the eluate after 56 days with added 0.5 M.-% NaCl unrelated to the BET surface results in the same classification of the four aggregates examined as the expansions in the 60 °C concrete prism test with 3% NaCl solution. In addition, the expansions found in the 60 °C concrete prism test with 10% NaCl solution correlated with the weighted excess SiO2 in eluate with added 2 M.-% NaCl without relation to the BET surface. Only in the case of the concrete test in accordance with the Alkali Guidelines did the relationship of the excess SiO2 in the eluate to the BET surface prove to be productive. Due to the potential of the solubility test with added NaCl for the evaluation of alkali sensitivity of aggregates in road surface concrete, we recommend continuing with comparative tests between solubility tests of grain samples of the various fractions and the concrete tests in accordance with ARS O4/13 with the greatest possible number of aggregates and a precisely defined investigation scope. KW - LIBS KW - Betonfahrbahndecke KW - Alkali-Kieselsäure-Reaktion KW - Gesteinskörnung KW - Alkaliempfindlichkeit KW - 3D-CT KW - Tausalzeintrag PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:hbz:opus-bast-25832 UR - https://bast.opus.hbz-nrw.de/frontdoor/index/index/docId/2583 SN - 978-3-95606-648-1 SN - 0943-9323 VL - S 165 SP - 1 EP - 111 PB - Fachverlag NW in der Carl Ed. Schünemann KG CY - Bremen AN - OPUS4-54755 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Weise, Frank A1 - von Werder, Julia A1 - Manninger, Tanja A1 - Maier, Bärbel A1 - Fladt, Matthias A1 - Simon, Sebastian A1 - Gardei, Andre A1 - Höhnel, Desirée A1 - Pirskawetz, Stephan A1 - Meng, Birgit T1 - A multiscale and multimethod approach to assess and mitigate concrete damage due to alkali-silica reaction N2 - Alkali-silica reaction (ASR) is a chemical reaction within concrete which can lead over time to cracking and spalling. Due to the complexity of the problem, it still causes damage to concrete constructions worldwide. The publication aims to illustrate the interdisciplinary research of the German Federal Institute for Materials Research and Testing (BAM) within the last 20 years, considering all aspects of ASR topics from the macro to the micro level. First, methods for characterization and assessment of ASR risks and reaction products used at BAM are explained and classified in the international context. Subsequently the added value of the research approach by combining different, preferably nondestructive, methods across all scales is explained using specific examples from a variety of research projects. Aspects covered range from the development of new test-setups to assess aggregate reactivity, to analysis of microstructure and reaction products using microscopical, spectroscopical and X-ray methods, to the development of a testing methodology for existing concrete pavements including in-depth analysis of the visual damage indicator and the de-icing salt input using innovative testing techniques. Finally, research regarding a novel avoidance strategy that makes use of internal hydrophobization of the concrete mix is presented. KW - Mitigation strategies KW - Concrete KW - Damage analysis KW - Alkali silica reaction KW - Road pavement KW - Accelerated testing KW - Non-destructive testing KW - Microstructure PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:101:1-2022052515100075090235 DO - https://doi.org/10.1002/adem.202101346 SN - 1527-2648 VL - 24 IS - 6 SP - 1 EP - 36 PB - Wiley-VCH CY - Weinheim AN - OPUS4-54951 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Babutzka, Martin A1 - Lehmann, Jens A1 - Burkert, Andreas T1 - Field exposure study under sheltered and open exposure conditions at different test sites in Germany: First‐year corrosion rate and atmospheric corrosivity N2 - The corrosivity of atmospheres in Europe has changed significantly in recent decades. For the Federal Republic of Germany, no current values for the corrosion rate based on 1‐year atmospheric exposure of standard specimens can be found in the scientific literature after 2000. This paper presents results from a field exposure study in the Berlin metropolitan area and Helgoland in 2016. Based on standard specimens, values for the corrosion rate and the corresponding atmospheric corrosivity category are determined for open exposure and indirect weathering in a ventilated enclosure as sheltering after 1 year of exposure. The results prove that determined corrosivity categories are material‐specific. Sheltered exposure is a typical atmospheric situation for many building components. It allows statements on the effect of the concentration of airborne substances on the corrosivity beyond the normative requirements. KW - Atmospheric corrosion KW - Corrosivity category KW - ISO 9223 KW - Mass loss KW - Atmosphärische Korrosion PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-565099 DO - https://doi.org/10.1002/maco.202213582 SN - 0947-5117 (print) SN - 1521-4176 (online) SP - 1 EP - 15 PB - Wiley-VCH GmbH CY - Weinheim AN - OPUS4-56509 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Burkert, Andreas T1 - Einfluss der Oberflächennachbearbeitung auf die Korrosionsbeständigkeit von Schweißnähten N2 - Bedingung für den schadensfreien Einsatz nichtrostender Stähle ist die vollständige Ausbildung der Passivschicht. Voraussetzung dafür sind glatte, blanke, saubere Oberfläche, eine gleichmäßige Elementverteilung, wenig Ausscheidungen und Verunreinigungen. Eine mögliche Beeinflussung der Gefügeausbildung durch Warmumformung und durch die schweißtechnische Verarbeitung sind zu beachten. Anlauffarben müssen durch geeignete geeignete chemische bzw. mechanische Nachbehandlung entfernt werden. Eine ausreichende Nachbehandlung kann durch elektrochemische Prüfverfahren ebenso sichergestellt werden wie mittels der KorroPad-Prüfmethode. Letzte ist einfach und schnell in der Anwendung und ermöglicht es dem Verarbeiter, die Geeignetheit einer Nachbehandlung zu überprüfen. T2 - Fachtagung Edelstahl Rostfrei CY - Dresden, Germany DA - 19.10.2023 KW - Nichtrostender Stahl KW - Korrosionsverhalten KW - Schweißnaht KW - Nachbearbeitung KW - KorroPad Prüfverfahren PY - 2023 AN - OPUS4-58703 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Babutzka, Martin A1 - Burkert, Andreas A1 - Heise, Svenja A1 - Heyn, A. T1 - Korrosionsuntersuchungen mit gelartigen Elektrolyten an Zink - Eine innovative Prüfmethodik N2 - Ein neuer Ansatz bei elektrochemischen Korrosionsuntersuchungen kann durch den Einsatz von gelartigen Elektrolyten als Alternative zu wässrigen Prüfelektrolyten beschritten werden. Gelartige Elektrolyte ermöglichen minimalinvasive Untersuchungen an natürlich gebildeten Zinkdeckschichten. Dadurch können korrosionsrelevante Kennwerte ermittelt werden, die Aussagen zur Deckschichtbildung und zur Stabilität von atmosphärisch gebildeten Deckschichten erlauben. In diesem Beitrag wird anhand verschiedener Untersuchungen an Reinzink der Mehrwert von gelartigen Elektrolyten für die Korrosionsforschung und -prüfung verdeutlicht. Darüber hinaus werden neue Erkenntnisse zur Deckschichtbildung von Zink unter atmosphärischen Bedingungen vorgestellt. T2 - GfKORR-Jahrestagung 2019 CY - Frankfurt a. M. DA - 12.11.2019 KW - Zink KW - Gelartige Elektrolyte KW - Korrosionsuntersuchungen KW - Deckschichtbildung PY - 2019 SN - 978-3-935406-71-0 SP - 53 EP - 64 AN - OPUS4-49642 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Erning, Johann Wilhelm T1 - Sprechen wir über Korrosion - aber richtig! N2 - Die Korrosion in ihren zahlreichen Erscheinungsformen beschäftigt Fachleute und Laien. Um-so wichtiger ist es, die einzelnen Phänomene korrekt und eindeutig zu benennen. Nur so kann man eine saubere Beschreibung der Korrosionsvorgänge erreichen und damit in der wörtlichen und schriftlichen Kommunikation richtig verstanden werden. An zahlreichen Beispielen wird der richtige und normgemäße Sprachgebrauch beschrieben. T2 - Korrosionsschutz in der maritimen Technik CY - Hamburg, Germany DA - 29.01.2020 KW - Korrosion KW - Nomenklatur PY - 2020 SN - 978-3-935406-72-7 SP - 7 EP - 11 AN - OPUS4-50327 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rütters, H. A1 - Fischer, S. A1 - Le, Quynh A1 - Bettge, Dirk A1 - Bäßler, Ralph A1 - Maßmann, J. A1 - Ostertag-Henning, C. A1 - Wolf, J. Lennard A1 - Pumpa, M. A1 - Lubenau, U. A1 - Knauer, S. A1 - Jaeger, P. A1 - Neumann, A. A1 - Svensson, K. A1 - Lempp, C. A1 - Menezes, F. A1 - Hagemann, B. T1 - Towards defining reasonable minimum composition thresholds – impacts of variable CO2 stream compositions on transport, injection and storage N2 - The collaborative project “Impacts of impurities in CO2 streams captured from different emitters in a regional cluster on transport, injection and storage (CLUSTER)” aimed to set up recommendations on how to define “reasonable minimum composition thresholds” that CO2 streams should meet when accessing CO2 transport pipeline networks. Within CLUSTER, we investigated potential impacts of CO2 streams with different and temporally variable compositions and mass flow rates along the whole CCS chain. Investigations included, amongst others, impacts on: Corrosion of pipeline steel, pipeline network design and related transport costs, alteration of well bore cements, pressure development and rock integrity, geochemical reactions, and petrophysical and geomechanical rock properties. All investigations are based on a generic CCS chain scenario. In this scenario, CO2 streams are captured from a spatial cluster of eleven emitters and collected in a regional pipeline network. Emitters comprise seven fossil fuel-fired power plants equipped with different capture technologies, two cement plants, one refinery and one integrated iron and steel plant. In total, 19.78 Mio t CO2 (including impurities) are captured in the emitter cluster annually. The combined CO2 stream is transported in a trunk line with a length of 400 km (100 km of these offshore) and is injected into five generic storage structures. The storage reservoirs are saline aquifers of the Buntsandstein. The investigations revealed beneficial and deteriorating impacts of different impurities and combinations thereof. Overall, no fundamental technical obstacles for transporting, injecting and storing CO2 streams of the modelled variable compositions and mass flow rates were observed. Based on the results, the CLUSTER project team recommends not to define “minimum composition thresholds” for CO2 streams as strict threshold values for each individual impurity in the stream. Instead, CO2 stream compositions and variabilities for specific CCS projects should be constrained with regard to a set of parameters including i) the overall CO2 content, ii) maximum contents of relevant impurities or elements, iii) acceptable variability of CO2 stream composition, and iv) impurity combinations to be avoided. T2 - 15th International Conference on Greenhouse Gas Control Technologies, GHGT-15 CY - Online meeting DA - 15.03.2021 KW - Corrosion KW - Impurities KW - CO2 quality KW - Pipeline network KW - Whole-chain CCS scenario KW - Recommendations PY - 2021 DO - https://doi.org/10.2139/ssrn.3816427 SP - 1 EP - 18 AN - OPUS4-52418 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Aristia, Gabriela A1 - Nofz, Marianne A1 - Bäßler, Ralph A1 - Sojref, Regine A1 - Le, Quynh Hoa T1 - Preliminary Study on Al2O3 Sol-Gel Coating for Corrosion Protection of Martensitic Stainless Steel in Artificial Geothermal Water N2 - Al2O3 coatings are often used as protective layers on steels against electrochemical and high-temperature corrosion because they are chemically inert and stable at elevated temperatures. This study presents preliminary work on the possibilities of using Al2O3 sol-gel coatings for corrosion protection of martensitic stainless steels in geothermal environments. Al2O3 sol-gel coatings were applied on UNS S42000, which is known to be susceptible to uniform and localized corrosion. The coated steel specimens were then tested in two types of artificial geothermal water, which simulate the geothermal fluids found in Sibayak (SBY), Indonesia, and North German Basin (NGB), Germany, respectively. SBY has pH 4 and 1.5 g/L of chloride ions, whereas NGB has a pH of 6 and 166 g/L of chloride ions. All experiments were carried out in autoclaves at 150 °C and 1 MPa under the deaerated condition. Evaluations were performed by investigating the surface profiles of both uncoated and coated steels before and after the corrosion test using a Laser Scanning Microscope (LSM) and Scanning Electron Microscope (SEM). Finally, Electrochemical Impedance Spectroscopy (EIS) was performed to compare the corrosion resistance of Al2O3 coated steels in SBY and NGB solutions. It was observed from the corrosion test that Al2O3 coatings are more suitable for use in the geothermal water with a higher pH. T2 - AMPP Annual International Corrosion Conference 2021 CY - Online Meeting DA - 19.04.2021 KW - Protective coating KW - Sol-gel coating KW - Geothermal KW - Martensitic steel KW - Corrosion PY - 2021 SP - 16777-01 EP - 16777-12 CY - Houston AN - OPUS4-52501 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Tian, H. A1 - Voigt, Marieke A1 - Lehmann, C. A1 - Meng, Birgit A1 - Stephan, D. ED - Middendorf, B. ED - Fehling, E. T1 - Composition and microstructure stability of cement compound under cyclic hydrothermal condition N2 - There have been many researches focused on the performance improvement of ultra-high performance concrete (UHPC) by autoclaving treatment. The goal of autoclaving is to increase the pozzolanic reaction, and to densify the cement stone and the transition zone which originates from the incorporation of supplementary cementitious materials (SCMs), such as silica fume, fly ash and blast furnace slag. Due to the superior properties, UHPC can also be utilized under high mechanical load and aggressive condition, for example, the fabrication of water tanks for thermal storage which is of great significance for saving energy and reducing CO2 emission. It is known that mineral stability of the hydration products of an inorganic binder is highly related to the temperature and pressure of the environment. A certain stable composition at room temperature, however, may undergo a phase transformation at high temperature and the performance decrease under this severe condition will generally be more severe. In this way, the rationale behind this deterioration under long-term hydrothermal condition involving many cycles and long duration has to be clarified, and then appropriate optimizing methods will be performed in order to obtain a kind of construction with high durability under aggressive environment. For this purpose, different types and amounts of SCMs are introduced into the standard mixture of UHPC and the phase compositions after autoclaving at 200 °C and 15.5 bar are determined by combined X-ray diffraction and scanning electron microscope. Mercury intrusion porosimeter is used to characterise the microstructure of the samples. In order to establish the relationship between microstructure and macroscopic properties, compressive and flexural strength are also investigated. T2 - HiPerMat 2020 CY - Kassel, Germany DA - 11.03.2020 KW - Hydrothermal treatment KW - UHPC KW - Composition PY - 2020 SN - 978-3-7376-0828-2 VL - 23 SP - 87 EP - 88 PB - Kassel University Press CY - Kassel AN - OPUS4-52375 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Metz, Christian A1 - Franz, Philipp A1 - Maierhofer, Christiane A1 - Wachtendorf, Volker A1 - Fischer, C. ED - Ziegahn, K.-F. T1 - Untersuchung der Beständigkeit additiv gefertigter Bauteile durch Thermografie nach künstlicher Bewitterung N2 - Additiv gefertigte Prüfkörper aus Polyamid 12 (Laser Sinter Verfahren) und Acrylnitril-Butadien-Styrol (Fused Layer Modeling Verfahren) wurden über 2000 Stunden künstlich bewittert und ihr Alterungsverhalten untersucht. Die Ergebnisse wurden anschließend mit denen von Prüfkörpern verglichen, welche auf dieselbe Weise künstlich bewittert, aber mittels konventionellem KunststoffSpritzguss hergestellt wurden. T2 - 48. Jahrestagung der GUS 2019 CY - Stutensee, Germany DA - 27.03.2019 KW - Polymere KW - Additive Fertigung KW - 3D Druck KW - Künstliche Bewitterung KW - Thermografie PY - 2019 SN - 978-3-9818507-3-4 VL - 48 SP - 207 EP - 216 CY - Pfinztal (Berghausen) AN - OPUS4-48502 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Geburtig, Anja A1 - Wachtendorf, Volker A1 - Trubiroha, P. T1 - Discussion on Weathering Reference Materials N2 - Weathering reference materials (WRMs) are used to characterize the harshness of an exposure, aiming on either reproducibility of a specific exposure or on the comparability between various kinds of natural or artificial weathering exposure. The materials that are used as weathering reference materials differ in their sensitivities (as well as in interactions and interferences of the latter), conditioned by the different processes which lead to the respective property change. It is also essential to take into account the necessary measurement equipment for the respective property change, in order to allow timely intervention. What are the key issues on choosing a weathering reference material? What can be learned from the weathering reference materials, investigated so far? Possibilities and limitations are discussed on the basis of existing weathering reference materials. Conclusions are drawn, for establishing new weathering reference materials. T2 - 9th European Weathering Symposium CY - Basel, Switzerland DA - 18.09.2019 KW - Temperature dependency KW - Weathering KW - Irradiation KW - Spectral sensitivity PY - 2019 SN - 978-3-9818507-5-8 SP - 283 EP - 292 PB - Thomas Würtz Grafik-Design CY - Karlsruhe, Germany AN - OPUS4-49150 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kamaraj, Abinaya A1 - Erning, Johann Wilhelm A1 - Reimann, S. A1 - Ahrens, A. T1 - Susceptibility of 304 stainless steel to crevice corrosion in electrochemically active fluids N2 - The susceptibility of AISI 304 stainless steel to crevice corrosion on the effect of contact with electrochemically active fluids was investigated using exposure and stepwise potentiostatic polarisation. Crevice materials made up of 304 SS and Polyether ether ketone (PEEK) forming two kinds of crevices including 304 SS-to-PEEK and 304 SS-to-304 SS were tested. T2 - NACE International Corrosion Conference 2019 CY - Nashville, TN, USA DA - 24.03.2019 KW - Steel KW - Crevice KW - Corrosion KW - ECA KW - Stainless PY - 2019 SP - Paper 12868 PB - NACE International CY - Houston AN - OPUS4-49286 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Lauhoff, Christian A1 - Degener, Sebastian A1 - Bolender, Artjom A1 - Liehr, Alexander A1 - Hübner, Leoni A1 - Frenck, Johanna-Maria A1 - Molotnikov, Andrey A1 - Niendorf, Thomas T1 - In Situ Synchrotron Diffraction Assessment of Reversibility of the Martensitic Transformation in Single-Crystalline Co–Ni–Ga Shape Memory Alloy Under Torsion N2 - AbstractHeusler-type Co–Ni–Ga shape memory alloys attracted significant attention due to their excellent functional properties in single-crystalline state under both compressive and tensile loading. The present study investigates the superelastic deformation behavior under torsion. Using a newly installed torsion testing setup, in situ synchrotron diffraction was carried out on single-crystalline material in order to investigate the martensitic phase transformation. Incremental deformation experiments reveal a fully reversible martensitic transformation under torsional loading at room temperature, leading to excellent strain recovery after deformation to 6.5% shear strain. Furthermore, relevant aspects towards the analysis of powder diffraction data obtained for single-crystalline material in transmission mode under torsional loading are presented and critically discussed. KW - Shape memory alloy KW - Pseudoelasticity KW - Martensitic transformation KW - Synchrotron diffraction KW - In situ testing KW - Torsion PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-621872 DO - https://doi.org/10.1007/s40830-024-00496-8 VL - 10 SP - 326 EP - 333 PB - Springer Science and Business Media LLC AN - OPUS4-62187 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Erning, Johann Wilhelm T1 - Anforderungen an den Einsatz von Metallen im Trinkwasser N2 - Die Trinkwasserverordnung gibt regulatorische Vorgaben zum Werkstoffeinsatz. Daneben existieren normative Hinweise zur Beständigkeit der Werkstoffe. Das Zusammenspiel der unterschiedlichen Vorgaben wird dargestellt und diskutiert T2 - Korrosionsverhalten bleifreier Kupfer-Zink-Legierungen im Kontakt mit Trinkwasser CY - Dresden, Germany DA - 11.10.2022 KW - Korrosion KW - Trinkwasser KW - Hygiene KW - Werkstoffe PY - 2022 AN - OPUS4-55982 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bäßler, Ralph T1 - Influence Of Brine Precipitates On Materials Performance In Geothermal Applications N2 - Significant Cu-deposition and precipitation only occurred in combination with carbon steel. High-alloyed materials prevent the disturbing Cu-agglomeration. Pb-deposition and precipitation only occurred in combination with carbon steel. No negative Pb-effect could be observed in combination with high-alloyed steels. High alloyed corrosion resistant alloys are suitable and shall be chosen for future design of the piping system, either in massive or in cladded form, to prevent unwanted interactions with brine components. T2 - AMPP Annual 2023 Conference CY - Denver, CO, USA DA - 19.03.2023 KW - Geothermal KW - Electrochemistry KW - Copper KW - Lead KW - Corrosion PY - 2023 AN - OPUS4-57237 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Fornacon-Wood, C. A1 - Stühler, M. R. A1 - Gallizioli, C. A1 - Manjunatha, B. R. A1 - Wachtendorf, Volker A1 - Schartel, Bernhard A1 - Plajer, A. J. T1 - Precise construction of weather-sensitive poly(ester-alt-thioesters) from phthalic thioanhydride and oxetane N2 - We report the selective ring opening copolymerisation (ROCOP) of oxetane and phthalic thioanhydride by a heterobimetallic Cr(III)K catalyst precisely yielding semi-crystalline alternating poly(esteralt- thioesters) which show improved degradability due to the thioester links in the polymer backbone. KW - Sulfur containing polymers KW - Durability KW - Weathering KW - Synthesis PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-590762 DO - https://doi.org/10.1039/d3cc03315e SN - 1364-548X VL - 59 IS - 76 SP - 11353 EP - 11356 PB - RSC AN - OPUS4-59076 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Stohl, Leonie A1 - Manninger, Tanja A1 - von Werder, Julia A1 - Dehn, F. A1 - Gorbushina, Anna A1 - Meng, Birgit T1 - Bioreceptivity of concrete - A review N2 - Materials that support natural biodiversity on their surfaces can compensate for human activities that have a negative impact on nature and thus contribute to a carbon-neutral and nature-positive world. Specifically designing bioreceptive materials which favor the growth of biofilms on their surface is an approach complementing conventional, macroscopic green façades. But what exactly characterizes a bioreceptive substrate and how do biofilm and substrate interact? How and why does a spontaneous colonization and the formation of biofilms take place? What are biofilms and how can they be established in a laboratory setting? How can this existing knowledge be transferred to the artificial stone concrete so that this material can be tuned to increase (or decrease) its bioreceptivity? This review paper aims at summarizing the existing state of knowledge on bioreceptive concrete and pointing out inconsistencies and contradictions which can only be removed by more interdisciplinary research in the field. KW - Bioreceptivity KW - Biofilm KW - Green facades KW - Developing building materials KW - Surface interactions KW - Concrete PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-581685 DO - https://doi.org/10.1016/j.jobe.2023.107201 SN - 2352-7102 VL - 76 SP - 1 EP - 17 PB - Elsevier AN - OPUS4-58168 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Wachtendorf, Volker A1 - Geburtig, Anja T1 - Digitale Umweltsimulation am Beispiel der Photooxidation von Polymeren N2 - Die Umweltwirkungen auf ein Material werden als Überlapp der Funktionskurven von Materialempfindlichkeit und einwirkenden Umweltparametern betrachtet. Wenn entweder die Empfindlichkeit oder die Beanspruchungen Null sind, ergibt sich auch keine Umweltwirkung und bei beidseitig Werten größer Null das jeweilige Produkt der beiden. Die Akkumulation der nicht-reversiblen Effekte über die Zeit und allen Eigenschaftsänderungen entspricht der Alterung des Materials für den jeweiligen Expositionszeitraum. Die digitale Umweltsimulation gliedert sich hier in drei Teilaspekte. Ein erster, rein materialwissenschaftlicher Teil hat die Aufgabe, alle relevanten Materialempfindlichkeiten experimentell zu quantifizieren. Ein zweiter – unter Umständen numerischer Teil – hat die Aufgabe, das Bauteil und seine Einbaulage zu digitalisieren und aus den makroskopischen Umgebungsbedingungen die relevanten mikroklimatischen Umweltparameter für alle Oberflächen- oder Volumenelemente zu bestimmen. In einem dritten Teil werden die Einwirkungen über den betrachteten Zeitraum berechnet und kumuliert. Dieses Konzept, das auf den so genannten Expositions-Reaktions-Funktionen (ERF) basiert, wird an Beispielen der Photoxidation erläutert. Dieses Vorgehen wurde schon beim ViPQuali-Projekt als Numerische Umweltsimulation umgesetzt. Überprüft werden muss das Modell unbedingt an einer realitätsnahen Validierungsbeanspruchung. Hier werden die ermittelten ERFs mit über den kompletten Beanspruchungszeitraum geloggten Umweltparametern gekoppelt, um die berechnete mit der experimentell erfahrenen Alterungswirkung zu vergleichen. Nur so kann sichergestellt sein, dass alle für die Anwendungsumgebung relevanten Materialempfindlichkeiten einbezogen wurden. T2 - 52. Jahrestagung der GUS CY - Stutensee-Blankenloch, Germany DA - 26.03.2024 KW - UV KW - Polymer 3R KW - Bewitterung KW - Bestrahlung PY - 2024 SN - 978-3-9826129-0-4 SP - 31 EP - 40 PB - Gesellschaft für Umweltsimulation e.V. CY - Pfinztal (Berghausen) AN - OPUS4-59830 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bäßler, Ralph T1 - ISO 27913 - Example For Successful Standardization Activities In The Field Of CCUS N2 - Since 2016 ISO Technical Committee (TC) 265 is working on standardization the whole CCS-process chain. Around 30 countries are working together to provide international guidelines. As ISO 27913 was the first standard finished within these activities it is already in the stage of first revision. The objective of ISO 27913 is “to provide specific requirements and recommendations on certain aspects of safe and reliable design, construction and operation of pipelines intended for the large-scale transportation of CO2 that are not already covered in existing pipeline standards such as ISO 13623, ASME B31.8, EN 1594, AS 2885 or other standards. Existing pipeline standards cover many of the issues related to the design and construction of CO2 pipelines; however, there are some CO2 specific issues that are not adequately covered in these standards. The purpose of this document is to cover these issues consistently. Hence, this document is not a standalone standard, but is written to be a supplement to other existing pipeline standards for natural gas or liquids for both onshore and offshore pipelines.” This contribution shall provide information on the content, the current stage of the revision process, encourage to contribute to this standard and make listeners aware to consider the influence of ISO standard on documents currently in draft. T2 - AMPP's Annual Conference + Expo 2024 CY - New Orleans, LA, USA DA - 02.03.2024 KW - Corrosion resistant materials KW - Carbon dioxide KW - Corrosion prevention KW - Standardization KW - CCUS KW - CCS KW - CCU PY - 2024 SP - 1 EP - 6 PB - AMPP CY - Houston AN - OPUS4-59735 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bäßler, Ralph A1 - Stoljarova, A. A1 - Regenspurg, S. T1 - Influence Of Brine Precipitates On Materials Performance In Geothermal Applications N2 - Since geothermal wells are a feasible energy source to replace fossil fuel supply, many technologies have been developed to take advantage of geothermal energy. Nevertheless, service conditions in geothermal facilities are in many cases extreme in terms of corrosion due to the chemical composition of hydrothermal fluids and temperatures. Therefore, materials selection based on preliminary material qualification is essential to guarantee a secure and reliable operation of the facilities. During operation of a geothermal research facility in Groß Schönebeck copper and lead effects have been found downhole. Occurring mechanisms and measures to prevent precipitation or scaling needed to be investigated as well as potential influences of such precipitates on corrosion resistance of metallic materials used for equipment. This contribution deals with the evaluation of the corrosion behavior of carbon steel and corrosion resistant alloys in copper and/or lead containing artificial geothermal water, simulating the conditions in the Northern German Basin. The behavior of these materials in an artificial geothermal water obtained by electrochemical measurements and exposure tests are presented. While carbon steel exhibits precipitation and deposition, higher alloyed material shows different response to such species and a higher resistance in saline geothermal water. Basing on these results the suitability of the investigated corrosion resistant alloy is given for use in such conditions, whereas carbon steel creates difficulties due to its susceptibility to Cu- and Pb-precipitation. T2 - AMPP Annual 2023 Conference CY - Denver, CO, USA DA - 19.03.2023 KW - Geothermal KW - Electrochemistry KW - Copper KW - Lead KW - Corrosion PY - 2023 SP - 1 EP - 15 PB - AMPP CY - Houston TX USA AN - OPUS4-57233 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rübner, Katrin T1 - HYTEGRA - Hydrothermalgranulate - Rohstoffliches Recycling von Mauerwerkbruch N2 - Ziel des Projekts HYTEGRA ist die Herstellung leichter Gesteinskörnungen durch hydrothermale Behandlung quarz- und kalkreicher Reststoffe. Als Ausgangsstoffe dienen heterogener Mauerwerkbruch aus Bau- und Abbruchabfällen als SiO2-Träger und Papierasche aus dem Altpapierrecycling als CaO-Träger. Für beide Reststoffe besteht derzeit ein Verwertungsdefizit. Das Verfahren beruht auf der Idee des rohstofflichen Recyclings, d. h. die chemisch-mineralogischen Stoffeigenschaften werden für die hydrothermale Stoffumwandlung genutzt. Bei der Härtung der Hydrothermalgranulate bilden sich Calciumsilicathydrat-Phasen (CSH) aus der Reaktion zwischen Quarzpartikeln und Kalk im Autoklav bei 200 °C und 16 bar Sattdampf. T2 - Innovationstag Mittelstand des BMWK am 22. Juni 2022 CY - Berlin, Germany DA - 23.06.2022 KW - Mauerwerkbruch KW - Papierasche KW - Rohstoffliches Recycling KW - Leichte Gesteinskörnung KW - Bodenfilter PY - 2022 AN - OPUS4-55552 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Baeßler, Matthias T1 - Maßgeblicher Einfluss geotechnischer Interaktionsprobleme auf den Tragwerksentwurf: Zwei spezielle Fallbeispiele N2 - Geotechnische Interaktionsprobleme können den Entwurf eines Tragwerks maßgeblich beeinflussen. Anhand zweier Fallbeispiele - dem Schotteroberbau auf Brücken im HGV und der Installation großer Monopiles - werden aktuelle Fälle aus dem Forschungsrepertoire der BAM vorgestellt. T2 - Geotechnische Seminarreihe am IBF des KIT CY - Karlsruhe, Germany DA - 23.01.2025 KW - Schotter auf Brücken im Hochgeschwindigkeitsverkehr KW - Pfahlfussbeulen KW - Beschleunigungsgrenzwert KW - Rammung KW - Monopiles PY - 2025 AN - OPUS4-62451 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Eilers, M. A1 - Alte-Teigeler, R. A1 - Borchers, R. A1 - Gallai, G. A1 - Habiger, D. A1 - Recknagel, Christoph A1 - Karczewski, B. A1 - Koll, J. A1 - Lorenz, S. A1 - Marossow, H. A1 - Schneider, Th. A1 - Seiffart, J. A1 - Stark, S. A1 - et al., T1 - Zusätzliche Technische Vertragsbedingungen und Richtlinien für Ingenieurbauten, Teil 6: Bauwerksausstattung, Abschnitt 7: Fahrbahnübergänge N2 - ZTV ING, Teil 6, Abschnitt 7) Zusätzliche Technische Vertragsbedingungen und Richtlinien für Ingenieurbauten, Teil 6: Bauwerksausstattung, Abschnitt 7: Fahrbahnübergänge KW - Brückenbeläge KW - Asphaltbauweisen KW - Fahrbahnübergänge PY - 2022 SN - 978-3-86446-344-0 VL - 782/7 SP - 1 EP - 30 PB - FGSV Verlag GmbH CY - Köln AN - OPUS4-56219 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Robens-Radermacher, Annika T1 - Coupling PGD model reduction with importance sampling using adaptive subset simulation for reliability analysis N2 - The key point of structural reliability analysis is the estimation of the failure probability. This probability is defined as the integral over the failure domain which is given by a limit state function. Usually, this function is only implicit given by an underlying finite element simulation of the structure. It is generally not possible to solve the integral analytically. For that reason, numerical methods based on sampling and surrogates have been developed. Nevertheless, these sampling methods still require a few thousand calculations of the underlying finite element model, making reliability analysis computationally expensive for relevant applications. Coupling a reduced order model (proper generalized decomposition) with an efficient variance reducing sampling algorithm can reduce the computational cost of reliability analysis drastically. In the proposed method, an importance sampling technique is coupled with a reduced structural model by means of PGD to estimate the failure probability. Instead of calculating the design point e.g. with optimization algorithms, the design point is adaptively estimated by using the idea of subset simulation. The failure probability is estimated in an iterative scheme based on adaptively computing the design point and refining the PGD model. T2 - 5th international Workshop Reduced Basis, POD and PGD Model Reduction Techniques (MORTech) 2019 CY - Paris, France DA - 19.11.2019 KW - Reliability KW - Probability of failure KW - Importance sampling KW - Proper Generalized Decomposition KW - Reduced order models PY - 2019 AN - OPUS4-49801 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kocherla, Amarteja T1 - Embedded Sensors for Quality Control and Structural Integrity Monitoring of Large scale 3DCP Structures N2 - Additive manufacturing of concrete structures is a novel and emerging technology. Free contouring in civil engineering, which allows for entirely new designs, is a significant advantage. Although several techniques and approaches demonstrate these advantages, quality control during printing is highly challeng-ing and rarely applied. Due to the continuous mixing process used in 3D concrete printing, it is impossible to exclude variations in the dry mixture or water content, and a single test sample is insufficient to represent the whole structure. A defect in one layer during printing can affect the integrity of the entire structure. T2 - 34th Annual Conference & Exhibition on non destructive evaluation & enabling technologies CY - Chennai, India DA - 12.12.2024 KW - Embedded sensors KW - Additive manufacturing KW - Concrete printing KW - Piezo sensors PY - 2024 AN - OPUS4-62546 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Munsch, Sarah Mandy T1 - 1H NMR Relaxometry: A Reliable Tool for Predicting Durability Properties? N2 - Resistance to carbonation and chloride migration are critical durability properties in cementitious construction materials. The ingress of CO2 and chlorides can lead to concrete deterioration and reinforcement corrosion, underscoring the importance of ensuring high resistance to these durability-reducing factors. Traditional methods, such as determinating the carbonation coefficient using standard procedures, are time-consuming and resource-intensive. These tests typically require 42 days of preconditioning, followed by 70 days before the final results can be determined using a phenolphthalein test, for a total duration of 112 days. In addition, some test chambers can only accommodate four samples at a time. In this study, we investigate whether 1H NMR relaxometry can effectively predict not only the carbonation resistance, KAC,3%, but also the chloride migration coefficient, DRCM, and the compressive strength, fc, of concrete, providing a method that could potentially streamline and accelerate the material development process by directing us quickly to potentially well-suited formulations. We performed measurements on non-carbonated fully saturated concrete and mortar samples at 28, 56, and 92 days using the NMR tomograph at BAM (8.9 MHz). Notably, the NMR measurements taken at 28 days showed no significant differences, suggesting that this timeframe is sufficient for meaningful results. The samples analyzed were drill cores, each 70 mm in diameter and approximately 120 mm in height. The NMR features we focused on included the initial amplitude E0, the x and y values of the dominant T2 relaxation time, and the logarithmic mean of the T2 relaxation time distribution. Another key feature was the surface relaxivity, which was determined by comparing the NMR curves with results from mercury intrusion porosimetry. We examined the correlation of these NMR features with the aforementioned durability properties, which were determined in a laboratory on sister samples using standard procedures. No chloride migration tests were performed on the mortar samples, and the carbonation procedure was carried out unter atmospheric conditions. The preliminary results show that the correlation factors for the NMR features with the carbonation coefficients of concrete were particularly remarkable. The strongest correlations were observed for the dominant relaxation time and the logarithmic mean, with values approaching 1. The preliminary results also indicate that there are high correlations between the compressive strength and amplitude-related features. In contrast, no strong correlations are observed for the DRCM. Although the results related to the mortar samples are still being analyzed, these initial correlations suggest that 1H NMR relaxometry could be a valuable tool for early assessment of material properties. Furthermore, the rapid and non-destructive nature of NMR measurements, requiring only a few minutes per sample, suggests that this technique has the potential to significantly accelerate the process of evaluating durability properties in cementitious materials. This capability also paves the way for the use of NMR features as input for AI-driven predictive models. T2 - Magnetic Resonance in Porous Media 2024 CY - Tromso, Norway DA - 26.08.2024 KW - Nuclear magnetic resonance KW - SLAMD KW - Carbonation KW - Durability PY - 2024 AN - OPUS4-61058 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Simon, Patrick T1 - Experimente in der Klimakammer N2 - Im Rahmen des Verbundtreffens des Vorhabens AISTEC werden akutelle Versuche aus der Großklimakammer des FB 7.2 präsentiert. T2 - 5. Verbundtreffen AISTEC CY - Online meeting DA - 24.06.2021 KW - Klimakammer KW - Stochastic Subspace Damage Detection KW - Model Update KW - Asphalt PY - 2021 AN - OPUS4-52869 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schönsee, Eric T1 - Investigations on multi-sensor data for monitoring volume flow N2 - Extrusion based 3D concrete printing (3DCP) is a growing technology because of its high potential for automating construction and the new possibilities of de-sign. In conventional construction methods, a sample is taken to be representative for one material batch. However, in 3DCP continuous mixing is used which re-sults in variations during the mixing process. Therefore, one sample is not repre-sentative for the entire structure. This leads to the necessity of continuous and re-al-time process monitoring. At the Bundesanstalt für Materialforschung und -prüfung (BAM), Berlin, a test rig is developed to allow for comprehensive monitoring of the printing process. For this purpose, sensors for torque, temperature, pressure and moisture are in-stalled into the pipe. A laser scanner is installed at the nozzle to acquire infor-mation about the geometry of the extruded material. This study focuses on the variations of pressure and temperature which are caused by changes in the material due to the ongoing mixing process. Preliminary results indicate that changes in the material properties cause changes in the sensor signals as well. These changes can be observed in various sensors with a delay, caused by material which is carried downstream. In the following, the data is ana-lysed to investigate if the changing material and the so caused change in pressure can be used to calculate volume flow. T2 - Digital Concrete 2024 CY - Munic, Germany DA - 04.09.2024 KW - 3D concrete printing KW - Monitoring KW - Pressure PY - 2024 AN - OPUS4-60997 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Klimek, André A1 - Hothan, Sascha A1 - Rogge, Andreas T1 - Investigation of Size Effects in Concrete Spalling T1 - Untersuchung des Maßstabseffekts auf das Abplatzverhalten von Beton N2 - Spalling of concrete due to fire exposure can lead to severe damage of building components. It is a much discussed subject in structural engineering and not yet completely understood. Generally, it is assumed that thermohydraulic and thermomechanical processes induce tensile stresses in the concrete. Furthermore, the tensile strength of concrete is reduced due to increasing temperatures. The combination of an increasing tensile stress and a decreasing tensile strength result in the occurrence of explosive spalling. The spalling behaviour of concrete is influenced by many parameters, for instance the water cement ratio, porosity, permeability of concrete as well, the presence of steel reinforcement and polypropylene fibres, also the size and geometry of the fire exposed area. Within the current research project at Bundesanstalt für Materialforschung und prüfung (BAM), the susceptibility to spalling of six different concrete mixtures is analysed to quantify the size effect using small scale, intermediate scale and full scale tests. A special fire test setup was built to test specimens simultaneously to enable a better comparability. All specimens are tested without additional mechanical load and unrestraint to prevent external induced cracking at the fire exposed site. Thermocouples are used to measure in situ the temperature distribution as an indication on the thermal degradation of the concrete during the fire tests. Afterwards the maximum spalling depth and the damaged area of the specimen are illustrated by a photogrammetric measurement system. The contribution to the spalling workshop presents the results of four concrete mixtures tested in intermediate-scale and full-scale fire tests. The comparisons are based on the concrete temperature as well as the obtained photogrammetric data. The results show that the spalling depth and the spalling area are significantly affected by the size of the fire exposed area. T2 - 6th International Workshop on Concrete Spalling due to Fire Exposure CY - Sheffield, UK DA - 19.09.2019 KW - Concrete KW - Spalling KW - Fire Test KW - Photogrammetry KW - Size Effect PY - 2019 UR - https://firespallingworkshop2019.group.shef.ac.uk/wp-content/uploads/2019/09/Fire-Spalling-Workshop_Proceedings.pdf SN - 978-1-5272-4135-0 SP - 61 EP - 70 PB - The University of Sheffield CY - Sheffield AN - OPUS4-49254 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schwettmann, K. A1 - Stephan, D. A1 - Nytus, N. A1 - Radenberg, M. A1 - Weigel, Sandra T1 - Post carbon road - The endless cycle of bitumen reuse N2 - In Germany, the reuse of asphalt has a long tradition. Since the 1980s, the reclaimed asphalt has been recycled achieving a reuse rate of around 90% and thus a very high value in the last years. In the future, instead of the amount, the quality of the reclaimed asphalt will be more important because the recycled asphalt will be reused again and again. Thus, these asphalt mixes are in the second or even third cycle of reuse. Concerning this situation, the question arises if asphalt can be reused several times without any loss in quality. An important factor affecting the asphalt quality is the binder bitumen. During the production, construction and service life, the ageing of this binder occurs causing a hardening of the bitumen. To compensate this hardening, additives for the reclaimed asphalt in terms of rejuvenation agents (rejuvenators) gain in importance. With these rejuvenators, the physical properties of bitumen can be modified e.g. the hardness and the stiffness reduced. However, the mechanism of the rejuvenation agents and the effects of the bitumen chemistry are largely unknown because the composition of the products varies very strongly. But with growing knowledge about these mechanisms and effects of the rejuvenation agents, the chemical composition and thus the physical and ageing behavior of bitumen can be targeted modified by the use of suitable rejuvenators. In this work, the actual results of the project Postcarbone road should be presented including investigations about the chemical and physical mechanisms as well as the efficiency of different rejuvenators. Further, a model for the cyclic reuse of bitumen should be developed. Based on this model, the choice of a suitable rejuvenation agent for the considered bitumen or rather asphalt should be possible. The project Postcarbone road (392670763) is funded by the German Research Foundation (DFG). T2 - 7th Eurasphalt and Eurobitume Comgress CY - Online meeting DA - 15.06.2021 KW - Bitumen KW - Multiple ageing and rejuvenation KW - Conventional testing KW - DSR KW - BBR KW - FTIR KW - Asphaltene content KW - Column chromatography PY - 2021 SP - 1 EP - 14 AN - OPUS4-53490 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Weise, Frank A1 - Stelzner, Ludwig T1 - Dauerhaftigkeit von Betonfahrbahn-Decken im deutschen Bundesautobahnnetz N2 - Die Dauerhaftigkeit der Betondecke und deren Oberflächentexturierung bestimmen maßgebend das Ge-brauchsverhalten von Betonfahrbahnen. Der Beitrag zeigt die Leistungsfähigkeit der Innenhydrophobierung als neuartige AKR-Vermeidungsstrategie zur Sicherstellung der geplanten, normativen Nutzungsdauer, auch unter Verwendung grenzwertig alkaliempfindlicher Gesteinskörnungen, auf. Zusätzlich wird eine neuartige Prüfmethodik zur in situ Verfolgung der 3D-Texturveränderungen auf einem erneuerten BAB-Abschnitt mit Grindingtextur vorgestellt. Diese beeinflussen maßgebend die Griffigkeit und die Reifen-Fahrbahn-Geräusche T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM Green Intelligent Building CY - Berlin, Germany DA - 16.10.2024 KW - Dauerhaftigkeit KW - Betonfahrbahndecken KW - Bundesautobahnnetz KW - Innenhydrophobierung PY - 2024 AN - OPUS4-61738 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Baeßler, Matthias T1 - OWEC repowering from a structural engineering and research perspective N2 - A significant number of new wind farms has to be installed and, at the same time, existing wind farms reaching the end of their planned life need to be reused efficiently to ensure that the ambitous goals for deploying offshore wind are met. Some relevant reuse alternatives for offshore wind farms are lifetime extension, repowering utilizing existing substructures and full replacement. In this presentation - starting from experience gained from extending the lifetime of the of the U1 metro viaduct in Berlin - we discuss end-of-life decision making in offshore wind. We focus particularly on issues concerning substructures and highlight existing challenges and opprtunities in research and development. T2 - RWE RePowering Event CY - Wilhelmshaven, Germany DA - 10.10.2023 KW - Offshore wind KW - End-of-life decision making KW - Repowering KW - Substructures PY - 2023 AN - OPUS4-58632 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Unger, Jörg F. T1 - Digital Twins for monitoring purposes N2 - In materials and component research, artificial intelligence methodologies will lead to massive upheavals in the coming years. The processes of material development, material processing, lifetime prediction and material characterization will change significantly. By combining AI methods and new forms of knowledge representation, the data-based management of product life cycles will take on new qualities. To address this emerging field of research Fraunhofer IWM set up the online workshop »AI Methods for Fatigue Behavior Assessment and Component Lifetime Prediction« T2 - Workshop “AI for materials fatigue assessment and machine component lifetime prediction” CY - Online meeting DA - 24.11.2021 KW - Digital twin KW - Model calibration KW - Parameter estimation KW - Ontology for model calibration PY - 2021 AN - OPUS4-53846 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Simon, Patrick T1 - Enhancing structural models with material tests and static response data - a case study considering a steel beam with asphalt layer subject to temperature variations N2 - Gradual or sudden changes in the state of structural systems caused, for example, by deterioration or accidental load events can influence their load-bearing capacity. Structural changes can be inferred from static and/or dynamic response data measured by structural health monitoring systems. However, they may be masked by variations in the structural response due to varying environmental conditions. Particularly, the interaction of nominally load-bearing components with nominally non-load bearing components exhibiting characteristics that vary as a function of the environmental conditions can significantly affect the monitored structural response. Ignoring these effects may hamper an inference of structural changes from the monitoring data. To address this issue, we adopt a probabilistic model-based framework as a basis for developing digital twins of structural systems that enable a prediction of the structural behavior under varying ambient condition. Within this framework, different types of data obtained from real the structural system can be applied to update the digital twin of the structural system using Bayesian methods and thus enhance predictions of the structural behavior. In this contribution, we implement the framework to develop a digital twin of a simply supported steel beam with an asphalt layer. It is formulated such that it can predict the static response of the beam in function of its temperature. In a climate chamber, the beam was subject to varying temperatures and its static response wass monitored. In addition, tests are performed to determine the temperature-dependent properties of the asphalt material. Bayesian system identification is applied to enhance the predictive capabilities of the digital twin based on the observed data. T2 - International Conference on Structural Health Monitoring of Intelligent Infrastructure (SHMII-10) CY - Online meeting DA - 30.06.2021 KW - Digital twin KW - Structural health monitoring KW - Material tests KW - Bayesian updating PY - 2021 AN - OPUS4-54130 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - von Werder, Julia T1 - Living Concrete Walls: Engineering Bioreceptivity and Biofilms N2 - Building envelopes are a natural habitat of subaerial biofilms and can be more or less prone to be colonized (i.e. to be bioreceptive). Focusing on the added value of biofilms on manmade substrates represents new aesthetic frontiers and reduces the use of biocides. Moreover, the metabolic processes of photosynthetic biofilms can positively influence human health and life quality in densely populated cities by converting or absorbing pollutants. In the presented research the bioreceptivity of concrete claddings for building facades is engineered to sustain either natural or artificial establishment of microalgae-dominated biofilms. To be able to differentiate between the intrinsic material properties and the climatic boundary conditions, the experimental design in the first step comprised different analyses with model mono- and multi-species biofilms in sterile conditions and a high control of the environmental parameters. Growth and vitality of the algal component of the biofilms has been assessed with Pulse-amplitude modulation (PAM) fluorometry. T2 - 78th RILEM Annual Week & RILEM International Conference on Sustainable Materials & Structures: Meeting the major challenges of the 21st century - SMS 2024 CY - Toulouse, France DA - 25.08.2024 KW - Bioreceptivity KW - Biofilm KW - Weathering KW - Concrete KW - PAM fluorometry KW - Carbonation PY - 2024 AN - OPUS4-62224 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Munsch, Sarah Mandy T1 - Study on the predictability of carbonation resistance of cementitous materials based on nmr features and the use of slamd N2 - This study explores the acceleration of material design in the concrete industry, focusing on improving carbonation resistance, a key factor in the durability of concrete structures. Traditional tests for carbonation resistance are lengthy, but with the construction industry aiming for sustainable production, finding a balance between carbonation resistance and CO2 footprint is crucial. Our research employs two innovative methods: 1. Applying the Sequential Learning App for Materials Discovery (SLAMD), an AI materials design framework, to an extensive dataset of real-world concrete compositions to selectively test materials that meet market demands: maximum durability, optimal eco-durability, and the best cost-durability trade-off. 2. Investigating 1H Nuclear Magnetic Resonance (NMR) relaxometry as a quick alternative for characterizing carbonation behavior, as it saves time compared to traditional tests and assesses the complete material's pore space. Specific NMR features are then integrated into the material design model, with the model's performance compared against traditional approaches. The results of our study are compelling, demonstrating that materials can be precisely tailored to meet specific requirements with minimal data points. This marks a significant stride in the concrete industry, indicating that NMR-based, low-fidelity surrogate characterizations, combined with a focused, data-driven design approach, can substantially accelerate the development of durable, sustainable concrete mixtures. T2 - Rilem Spring Convention & Conference CY - Milan, Italy DA - 10.04.2024 KW - Nuclear magnetic resonance KW - Carbonation resistance KW - Cement and concrete KW - SLAMD app KW - Predictability PY - 2024 AN - OPUS4-60000 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rogge, Andreas T1 - Wissenschaftliche Perspektiven einer dauerhaften und zuverlässigen Verkehrsinfrastruktur N2 - Der Erhalt einer dauerhaft sicheren Infrastruktur erfordert neben der Berücksichtigung technisch bedingter Alterungs- und Schädigungsprozesse auch die Umsetzung aktueller gesellschaftlicher Herausforderungen wie die Integration neuer Mobilitätskonzepte, Steigerung der Resilienz gegenüber Klimawandel oder Ressourcenschonung. Die parallele Umsetzung dieser „alten“ und „neuen“ Anforderungen lässt sich nur durch räumlich und zeitlich skalenübergreifende Betrachtungen lösen, die ohne digitale Prozesse nicht möglich sein werden. Am Beispiel des Elements der Querscheinfuge in Betonstraßenoberflächen wird in diesem Vortrag aufgezeigt, wie die BAM durch Kombination diverser Projekte zu einzelnen Aspekten dieser Fragestellung in einem ganzheitlichen Konzept eines digitalen Zwillings dieses Bauelements löst. T2 - Forschungskolloquium Betonstraßenbau CY - Dresden, Germany DA - 19.01.23 KW - Alterungs- und Schädigungsprozesse KW - Mobilitätskonzepte KW - Verkehrsinfrastruktur PY - 2023 AN - OPUS4-56956 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Stelzner, Ludwig T1 - Feuerwiderstand vorgespannter Carbonbetondecken – Abplatz- und Hochtemperaturverhalten N2 - Der Einsatz von hoch zugbeanspruchbarem und korrosionsbeständigem Carbongelege anstelle herkömmlichen Spannstahls ermöglicht es Beton vorzuspannen und gleichzeitig die Betondeckung auf ein für den Verbund nötiges Minimum zu reduzieren. Der Wechsel von massiven zu filigranen Bauteilen führt in der Regel aufgrund der geringeren thermischen Masse zu einer Abnahme des Feuerwiderstandes. Der Beitrag stellt Versuchsergebnisse zum Abplatzverhalten von Carbonbeton vor, die im Rahmen des Verbundvorhabens „Vorgespannte Carbonbetondecken mit reduzierten Querschnitten“ (CaPreFloor) erzielt wurden. T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM Green Intelligent Building CY - Berlin, Germany DA - 16.10.2024 KW - Abplatzverhalten KW - CaPreFloor KW - Carbonbeton KW - Feuerwiderstand PY - 2024 AN - OPUS4-61424 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Weise, Frank A1 - Müller, U. A1 - Hüsken, Götz A1 - Gardei, Andre T1 - Begutachtung Berliner Tuffsteinfassaden - Turmruine der Kaiser-Wilhelm-Gedächtniskirche und Charlottenburger Tor N2 - Am Ende des 19. und zu Beginn des 20. Jahrhunderts wurden auch in Berlin vermehrt Bauwerke mit einer Fassadenverblendung aus Eifeler Tuffsteinen errichtet. Die Eifeler Tuffsteine zeichnen sich aufgrund ihrer hohen Porosität einerseits durch eine gute Verarbeitbarkeit aus. Andererseits sind sie nur schwach gebunden und besitzen deshalb eine geringe Verwitterungsbeständigkeit. T2 - Workshop Kulturguterhaltung - Vom Dampfkessel zu Nanomaterialien CY - Berlin, Germany DA - 17.11.2021 KW - Fassade KW - Tuffstein KW - Schalenbildung PY - 2021 SN - 2567-1251 VL - 3 SP - 107 EP - 123 PB - Druckerei G. Bohm CY - Berlin AN - OPUS4-54461 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Rübner, Katrin A1 - Seher, Julia A1 - Hahn, A. A1 - Schnell, A. ED - Rohs, M. ED - Weichold, O. T1 - Hydrothermale Herstellung von Filter- und Speichermaterialien aus SiO2- und CaO-reichen Reststoffen N2 - Aus SiO2- und CaO-reichen Sekundärrohstoffen können in einem hydrothermalen Stoffumwandlungsprozess poröse Körnungen (Hydrothermalgranulate HTG) hergestellt werden. Die Erhärtung der HTG erfolgt dabei in einem Autoklav bei ca. 200 °C und 1,6 MPa Sattdampf ähnlich dem Prozess der Kalksandsteinherstellung. Festigkeit und Gefüge der HTG entwickeln sich durch die Ausbildung von Calciumsilicathydraten (CSH-Phasen), die durch die Reaktion zwischen Quarzpartikeln (SiO2) und Kalk (CaO) entstehen. SiO2-Lieferant ist ziegelhaltiger Mauerwerkbruch, der als Hauptmineralphase Quarz enthält. Papierasche kann mit ihren Anteilen an Freikalk und anderen reaktive Calciumverbindungen als Kalkersatz dienen. Über die Mischungszusammensetzung und die Reaktionsbedingungen werden die Eigenschaften der Reaktionsprodukte gezielt gesteuert. Die HTG haben Rohdichten kleiner als 2000 kg/m³. Ihr Gefüge ist durch ein eher ungeordnetes System an Mesoporen und kleinen Makroporen mit Porenweiten kleiner 100 nm gekennzeichnet. Diese Porenstruktureigenschaften legen eine Anwendung der HTG als Filter- oder Speichermaterial nahe. Sie können natürliche Rohstoffe, wie Bims, Lavasand und fluviale Sande, aus Primärrohstoffen hergestellte Produkte, wie Blähton, Keramik und Aktivkohle, sowie erdölbasierte Kunststoffadditive ersetzen, wobei die typischen Filter- und Speichereigenschaften der herkömmlichen Produkte nahezu erreicht werden. Dadurch wird einerseits für Reststoffe, die gegenwärtig ein hohes Verwertungsdefizit aufweisen, eine hochwertige Wieder- bzw. Weiterverwertungsmöglichkeit geschaffen und die Abfallmenge vermindert. Andererseits erfolgt eine Schonung von knapper werdenden natürlichen mineralischen Rohstoffen und Erdöl. In einem Forschungsprojekt werden derzeit die technischen Möglichkeiten der hydrothermalen Herstellung von leichten porösen Körnungen aus Mauerwerkbruch, Kalk und Papierasche sowie die Anwendung der HTG als Filtermaterial in Bodenfiltern zur Abwasserreinigung und als Wasserreservoir in Substraten von Pflanzwänden und zur inneren Nachbehandlung hochfester Betone systematisch untersucht. Der Beitrag berichtet insbesondere über die experimentelle Entwicklung der hydrothermalen Synthesestrategie, die nachfolgende Charakterisierung der HTG und die Beziehungen zwischen Gefügekennwerten und technischen Eigenschaften der Körnungen. KW - Hydrothermale Synthese KW - Filtermaterial KW - Speichermaterial KW - Reststoffe KW - Mauerwerkbruch KW - Papierasche KW - Rohstoffliches Recycling PY - 2019 SN - 978-3-947197-13-2 VL - 54 SP - 183 EP - 190 PB - Gesellschaft Deutscher Chemiker e.V. CY - Frankfurt/Main ET - 1. AN - OPUS4-50207 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Viefhues, Eva T1 - Subspace-based Damage Detection with Rejection of the Temperature Effect and Uncertainty in the Reference N2 - Temperature variation can be a nuisance that perturbs vibration based structural health monitoring (SHM) approaches for civil engineering structures. In this paper, temperature affected vibration data is evaluated within a stochastic damage detection framework, which relies on a null space based residual. Besides two existing temperature rejection approaches – building a reference state from an averaging method or a piecewise method – a new approach is proposed, using model interpolation. In this approach, a General reference model is obtained from data in the reference state at several known reference temperatures. Then, for a particular tested temperature, a local reference model is derived from the general reference model. Thus, a well fitting reference null space for the formulation of a residual is available when new data is tested for damage detection at an arbitrary temperature. Particular attention is paid to the computation of the residual covariance, taking into account the uncertainty related to the null space Matrix estimate. This improves the test performance, contrary to prior methods, for local and global damages, resulting in a higher probability of detection (PoD) for the new interpolation approach compared to previous approaches. T2 - International Operational Modal Analysis Conference CY - Copenhagen, Danmark DA - 13.05.2019 KW - Un- certainty KW - Statistical method KW - Subspace-based method KW - Temperature rejection KW - Model interpolation PY - 2019 AN - OPUS4-48244 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Stohl, Leonie T1 - Funktionalisierter Beton: Biorezeptivität von strukturiertem UHPC N2 - Understanding the fundamentals of bioreceptivity enables the developement of functionalized materials. Concrete as the most used building material worldwide is of special interest as microbially greened panels may represent an alternative to classic façade greening with plants. As standards are not ye established, material characterization in context as well as bioreceptivity assessment itself has been proven to be difficult. The presentation reviews first results of methods adapted for this application. T2 - Tagung des Instituts für Bioanalytik: Bewertung biozidhaltiger Baustoffe CY - Augsburg, Germany DA - 29.06.2023 KW - Biorezeptivität KW - Beton KW - UHPC KW - Biofilm PY - 2023 AN - OPUS4-58375 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Nandish, Ranjith A1 - Knaust, Christian A1 - Zehfuß, Jochen T1 - Numerical Investigations of a Large Fire Exposure Crib Test—Presenting Different Pyrolysis Modelling Methodologies and Numerical Results N2 - ABSTRACTThe need for numerical‐based approaches to investigate the fire behaviour in buildings with combustible components is growing due to the increasing use of timber by the construction industry to meet the ‘Climate Action Plan 2050’. This requires consideration of the complex kinetic processes that take place during the burning of the wood in the numerical models. This is accomplished by using computational fluid dynamics (CFD) to numerically model the material pyrolysis and combustion processes. This article presents three different approaches for simulating the behaviour of a wood crib fire using the fire dynamics simulator (FDS). These approaches are based on either prescribing the burning rate of the wood directly from the physical experiments or using the kinetic parameters to govern the underlying processes, such as pyrolysis. Wooden crib fire experiments carried out by the RISE Research Institute in Sweden inside the combustion chamber that were used to validate all the methods. The numerical results from the method, that utilised the experimentally determined burning rate, were in good agreement with the experimental results, with a maximum deviation of 6% in the case of HRR. On the other hand, the model that needs kinetic parameters as its input has shown maximum discrepancies of 12% and 33% compared to experimental results. These methods are sensitive to the input parameters and the extent of dependency needs further investigation. KW - Pyrolysis KW - Wood combustion KW - Wood fire loads KW - Wooden buildings PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-626567 DO - https://doi.org/10.1002/fam.3287 SN - 1099-1018 VL - 49 IS - 4 SP - 371 EP - 387 PB - John Wiley & Sons Ltd. AN - OPUS4-62656 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Baeßler, Matthias A1 - Herrmann, Ralf A1 - Hille, Falk A1 - Wille, Frank T1 - Dynamisches Verhalten und Überwachung des Großen Fallturms der BAM in Horstwalde N2 - Falltürme sind Bauwerke, die als Versuchsanlagen sehr speziellen, impulsartigen Belastungen ausgesetzt sind. Am Fallturm auf dem Testgelände Technische Sicherheit (TTS) der BAM wurde bei Routineinspektionen eine Abnahme der strukturellen Integrität in Form von Vorspannungsverlusten in den Bolzen der Stahlverbindungen festgestellt. Um ein Verständnis für die zugrundeliegenden Trag- und Schädigungsmechanismen zu erlangen, wurde ein umfassendes Structural Health Monitoring (SHM) System geplant und am Bauwerk installiert unter Nutzung von digitalen Bauwerksmodellen. Für die Auslegung des Überwachungssystems, insbesondere aber zur Unterstützung der Untersuchung des Schädigungsprozesses, wurden Finite-Elemente-Modelle erstellt. Um sicherzustellen, dass die FE-Modelle das reale Tragwerksverhalten mit ausreichender Genauigkeit abbilden, mussten sie jedoch in Bezug auf die gemessenen Antworten des Tragwerks kalibriert werden. Der vorliegende Beitrag beschreibt experimentelle und numerische Untersuchungen zur Identifizierung des strukturellen Systems des Stahlrohrgitterturms in Vorbereitung einer Überwachungskampagne. Die Auswertung von gemessenen Schwingungen unter ambienter Anregung ermöglichte die Identifizierung der Eigenfrequenzen mehrerer globaler Schwingungsmoden des Fallturms. Zur Modellvalidierung wurde zunächst eine Sensitivitätsanalyse durchgeführt, um die Parameter mit dem größten Einfluss zu ermitteln. Anschließend wurde ein evolutionärer Algorithmus (EA) zur Optimierung nach dem Prinzip der Minimierung der Differenzen zwischen gemessenen und simulierten charakteristischen Antworten eingesetzt. Das aktualisierte Modell wurde schließlich an der dynamischen Reaktion der Turmstruktur infolge einer realen Falltest-induzierten Stoßbelastung validiert. Die Ergebnisse zeigten eine gute Übereinstimmung zwischen numerischen und experimentellen Ergebnissen. N2 - Drop test towers are structures subjected to very specific dynamic loadings. At the drop test tower at the Test Site Technical Safety (TTS) of BAM routine inspections revealed a decline of structural integrity in form of loss of pretension in bolts of structural steel connections. To get an understanding about the underlying damage mechanisms as well as to assure the structural safety in operation, a multifaceted Structural Health Monitoring (SHM) system was planned and installed at the structure with the help of digital models. For planning the monitoring system but especially for supporting the investigation of the damaging process finite element models are deployed. Though, to ensure the capability of the FE model to reproduce the real structural behavior in sufficient accuracy, it needs to be calibrated in respect to measured responses of the structure. The present contribution describes experimental and numerical investigations to identify the structural system of the steel tube lattice tower in preparation of the monitoring campaign. An ambient vibration test allowed the identification of the natural frequencies of several global vibrational modes of the drop test tower. For model updating first a sensitivity analysis is applied to identify the most influencing parameter. In succession a genetic algorithm was applied for optimization in the sense of minimization of the difference between measured and simulated characteristic responses. The updated model is finally validated on the dynamic response of the tower structure to a real drop test induced impact loading. The results showed a good agreement between numerical and experimental results though the robustness of the simulation should be improved by more sophisticated numerical modelling. T2 - 7. VDI-Fachtagung Baudynamik CY - Würzburg, Germany DA - 27.04.2022 KW - Großer Fallturm Horstwalde KW - Structural Health Monitoring KW - Belastungsversuch KW - Modalanalyse KW - Schwingungsdynamik KW - Finite Elemente Simulation PY - 2022 SN - 978-3-18-092379-6 SN - 978-3-18-102379-2 DO - https://doi.org/10.51202/9783181023792-265 SN - 0083-5560 VL - 2379 SP - 265 EP - 284 PB - VDI-Verlag CY - Düsseldorf AN - OPUS4-55472 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Suffa, Philipp A1 - Kemmler, Samuel A1 - Koestler, Harald A1 - Ruede, Ulrich T1 - Large-scale simulations of fully resolved complex moving geometries with partially saturated cells N2 - We employ the Partially Saturated Cells Method to model the interaction between the fluid flow and solid moving objects as an extension to the conventional lattice Boltzmann method. We introduce an efficient and accurate method for mapping complex moving geometries onto uniform Cartesian grids suitable for massively parallel processing. A validation of the physical accuracy of the solid–fluid coupling and the proposed mapping of complex geometries is presented. The implementation is integrated into the code generation pipeline of the waLBerla framework so that highly optimized kernels for Central Processing Unit (CPU) and Graphical Processing Unit (GPU) architectures become available. We study the node-level performance of the automatically generated solver routines. 71% of the theoretical peak performance can be achieved on CPU nodes and 86% on GPU accelerated nodes. Only a moderate overhead is observed for the processing of the solid–fluid coupling when compared to the fluids simulations without moving objects. Finally, a counter-rotating open rotor is presented as a prototype industrial scenario, resulting in a mesh size involving up to 4.3 × 109 fluid grid cells. For this scenario, excellent parallel efficiency is reported in a strong scaling study on up to 32 768 CPU cores on the LUMI-C supercomputer and on up to 1024 NVIDIA A100 GPUs on the JUWELS Booster system. KW - Computational fluid dynamics KW - Lattice Boltzmann methods KW - Fluid coupling KW - Turbulent flows KW - Supercomputer PY - 2025 DO - https://doi.org/10.1063/5.0268021 SN - 1070-6631 VL - 37 IS - 5 SP - 1 EP - 13 PB - AIP Publishing AN - OPUS4-63188 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Geburtig, Anja T1 - Digitale Umweltsimulation am Beispiel der Photooxidation von Polymeren N2 - Die Umweltwirkungen auf ein Material werden als Überlapp der Funktionskurven von Materialempfindlichkeit und einwirkenden Umweltparametern betrachtet. Wenn entweder die Empfindlichkeit oder die Beanspruchungen Null sind, ergibt sich auch keine Umweltwirkung und bei beidseitig Werten größer Null das jeweilige Produkt der beiden. Die Akkumulation der nicht-reversiblen Effekte über die Zeit und allen Eigenschaftsänderungen entspricht der Alterung des Materials für den jeweiligen Expositionszeitraum. Die digitale Umweltsimulation gliedert sich hier in drei Teilaspekte. Ein erster, rein materialwissenschaftlicher Teil hat die Aufgabe, alle relevanten Materialempfindlichkeiten experimentell zu quantifizieren. Ein zweiter – unter Umständen numerischer Teil – hat die Aufgabe, das Bauteil und seine Einbaulage zu digitalisieren und aus den makroskopischen Umgebungsbedingungen die relevanten mikroklimatischen Umweltparameter für alle Oberflächen- oder Volumenelemente zu bestimmen. In einem dritten Teil werden die Einwirkungen über den betrachteten Zeitraum berechnet und kumuliert. Dieses Konzept, das auf den so genannten Expositions-Reaktions-Funktionen (ERF) basiert, wird an Beispielen der Photoxidation erläutert. Dieses Vorgehen wurde schon beim ViPQuali-Projekt als Numerische Umweltsimulation umgesetzt. Überprüft werden muss das Modell unbedingt an einer realitätsnahen Validierungsbeanspruchung. Hier werden die ermittelten ERFs mit über den kompletten Beanspruchungszeitraum geloggten Umweltparametern gekoppelt, um die berechnete mit der experimentell erfahrenen Alterungswirkung zu vergleichen. Nur so kann sichergestellt sein, dass alle für die Anwendungsumgebung relevanten Materialempfindlichkeiten einbezogen wurden. T2 - 52. Jahrestagung der GUS CY - Blankenloch, Germany DA - 26.03.2024 KW - Polymer 3R KW - UV KW - Bestrahlung KW - Bewitterung PY - 2024 AN - OPUS4-59831 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Babutzka, Martin T1 - Korrosionsuntersuchungen mit gelartigen Elektrolyten an Zink - Eine innovative Prüfmethodik N2 - Ein neuer Ansatz bei elektrochemischen Korrosionsuntersuchungen kann durch den Einsatz von gelartigen Elektrolyten als Alternative zu wässrigen Prüfelektrolyten beschritten werden. Gelartige Elektrolyte ermöglichen minimalinvasive Untersuchungen an natürlich gebildeten Zinkdeckschichten. Dadurch können korrosionsrelevante Kennwerte ermittelt werden, die Aussagen zur Deckschichtbildung und zur Stabilität von atmosphärisch gebildeten Deckschichten erlauben. In diesem Beitrag wird anhand verschiedener Untersuchungen an Reinzink der Mehrwert von gelartigen Elektrolyten für die Korrosionsforschung und -prüfung verdeutlicht. Darüber hinaus werden neue Erkenntnisse zur Deckschichtbildung von Zink unter atmosphärischen Bedingungen vorgestellt. T2 - GfKORR-Jahrestagung 2019 CY - Frankfurt a. M., Germany DA - 12.11.2019 KW - Zink KW - Gelartige Elektrolyte KW - Korrosionsuntersuchungen KW - Deckschichtbildung PY - 2019 AN - OPUS4-49641 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kauss, Norman T1 - Detektion von Sensibilisierung am nichtrostenden Lean-Duplex-Stahl 1.4062 mit verschiedenen elektrochemischen Methoden N2 - Vorstellung von EPR, Ekrit, CPT und KorroPad zur Erfassung von Sensibilisierung am Lean Duplex 1.4062 an verschieden wärmebehandelten Zuständen. T2 - GfKORR-Arbeitskreis "Korrosion und Korrosionsschutz von Eisen und Stahl" CY - Duisburg, Germany DA - 12.12.2019 KW - Lean Duplex KW - Sensibilisierung KW - Lochkorrosion KW - EPR KW - KorroPad KW - Altern PY - 2019 AN - OPUS4-50182 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kauss, Norman T1 - Detektion von Sensibilisierung am nichtrostenden Lean-Duplex-Stahl 1.4062 mit verschiedenen elektrochemischen Methoden N2 - Vergleich von EPR, EKrit, CPT und KorroPad zur Ermittlung von Sensibilisierung an dem bei 600 °C gealterten Lean Duplex 1.4062. T2 - Korrosionsuntersuchung und -überwachung" und "Grundlagen und Simulation" CY - Dusseldorf, Germany DA - 21.11.2019 KW - Lean Duplex KW - Sensibilisierung KW - Lochkorrosion KW - EPR KW - KorroPad KW - Altern PY - 2019 AN - OPUS4-50180 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Erning, Johann Wilhelm T1 - Wie gehe ich bei einer Schadensuntersuchung vor? N2 - Die Vorgehensweise einer Schadensuntersuchung wird in Schritten erklärt und wichtige Einzelthemen diskutiert. T2 - Der sichere Einsatz von Werkstoffen aus Kupfer und Kupferlegierungen in der Trinkwasserinstallation CY - Iserlohn, Germany DA - 12.12.2019 KW - Schadensanalyse KW - Vorgehensweise PY - 2019 AN - OPUS4-50185 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Erning, Johann Wilhelm T1 - Planung und Betrieb von Trinkwasserinstallationen: Was uns das Regelwerk sagt N2 - Die aktuellen Vorgaben aus gesetzlichen Regelungen und dem technischen Regelwerk für die Planung, Erstellung und den Betrieb einer Trinkwasserinstallation werden dargelegt. Beispiele für einzelne Punkte werden gegeben. T2 - Der sichere Einsatz von Werkstoffen aus Kupfer und Kupferlegierungen in der Trinkwasserinstallation CY - Iserlohn, Germany DA - 12.12.2019 KW - Werkstoffe KW - Trinkwasserinstalltion KW - Sicherer Betrieb KW - Wartung PY - 2019 AN - OPUS4-50184 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Geburtig, Anja T1 - Discussion on Weathering Reference Materials N2 - Weathering reference materials are used to characterize the harshness of an exposure, aiming on either reproducibility of a specific exposure or on the comparability between various kinds of weathering exposure. The materials that are used as weathering reference materials differ in their sensitivities (as well as in interactions and interferences of the latter), conditioned by the different processes which lead to the respective property change. It is also essential to take into account the necessary measurement equipment for the respective property change, in order to allow timely intervention. What are the key issues on choosing a weathering reference material? What can be learned from the weathering reference materials, investigated so far? Possibilities and limitations are discussed on the basis of existing weathering reference materials. Conclusions are drawn, for establishing new weathering reference materials. T2 - 9th European Weathering Symposium CY - Basel, Switzerland DA - 18.09.2019 KW - Plastic KW - Ageing KW - Fragmentation KW - Environment KW - Digital twin PY - 2019 AN - OPUS4-49713 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Geburtig, Anja T1 - Messung der effektiven UV-Bestrahlung bei der Bewitterung von Polymeren N2 - Bei der Bestrahlung und Bewitterung von polymeren Werkstoffen wird die Degradation durch eine Absorption von Strahlung initiiert und meistens durch weitere Klimagrößen, wie z.B. Wärme, Feuchte und atmosphärische Gase beeinflusst. Die Messung einer effektiven Bestrahlungsstärke und ihre zeitliche Integration sind deshalb von großer Bedeutung. Photochemische Prozesse werden beim Sehen oder allgemeiner bei Farbstoffen schon durch sichtbare (VIS) Strahlung, dagegen bei der Erythembildung der Haut und der Photodegradation von Polymeren erst durch die energiereicheren Photonen der ultravioletten (UV) Strahlung initiiert. Die spektrale Empfindlichkeit des Auges und die Erythembildung sind im VIS- bzw. UV-Bereich sehr stark wellenlängenabhängig, was durch die Angabe der mit der spektralen Hellempfindlichkeit V() des Auges bewerteten VIS-Strahlung in Lux (lx) bzw. die mit der Erythem-Wirkfunktion bewertete UV Strahlung als dimensionsloser UV-Index berücksichtigt wird. Spektrale Empfindlichkeiten. Die Photodegradation von Polymeren ist im UV-Bereich ebenfalls stark wellenlängenab-hängig, was bisher nicht berücksichtigt wurde. Seit Mitte der 70er Jahre, als die lx- bzw lxh- Messung bei der Strahlungsbeanspruchung langsam durch die Ermittlung der radiometrischen UV-Bestrahlungsstärke bzw. der UV-Bestrahlung im gesamten UV-Bereich abgelöst wurde, gab es hier bei der Bewitterungsprüfung keine weiteren Fortschritte auf dem Gebiet der Charakterisierung der Strahlungsbeanspruchung im UV-Bereich. Seit Jahren liegen zahlreiche Ergebnisse über die spektrale Empfindlichkeit von Photo-degradationsprozessen vor, die zeigen, dass die spektrale Empfindlichkeit im Bereich der Globalstrahlung bei ca. 300 nm, am größten ist und im langwelligen UV-Bereich bei ca. 400 nm gegen Null geht. Die Messungen der radiometrischen Größen UV-Gesamt-bestrahlungsstärke und UV-Gesamtbestrahlung erfasst deshalb über weite Wellen-längenbereiche Strahlungsanteile, die für die Photodegradation bedeutungslos sind und mittelt über potenziell bedeutsame Änderungen im kurzwelligen UV-Bereich hinweg. Es wird das Konzept eines neuen UV-Radiometers vorgestellt, dessen spektrale Empfindlichkeit einer mittleren spektralen Empfindlichkeit der Photodegradation von Polymeren entspricht. Die effektive UV-Bestrahlungsstärke und UV-Bestrahlung kann dadurch wesentlich genauer erfasst werden. T2 - 48. Jahrestagung der GUS 2019 CY - Stutensee, Germany DA - 27.03.2019 KW - UV-Bestrahlungsstärke PY - 2019 AN - OPUS4-49712 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Aristia, Gabriela T1 - Fenomena Korosi pada aplikasi panas bumi N2 - To accelerate the development of Indonesian geothermal energy, progress should be done in all aspects. Corrosion is an important part on the technological development to ensure the safety and longevity of a power plant. T2 - Fireside Chat der Indonesischen Botschaft CY - Berlin, Germany DA - 21.11.2019 KW - Corrosion KW - Korosi KW - Korrosion PY - 2019 AN - OPUS4-49735 LA - mul AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Erning, Johann Wilhelm T1 - Sprechen wir über Korrosion - aber richtig! N2 - Die Korrosion in ihren zahlreichen Erscheinungsformen beschäftigt Fachleute und Laien. Um-so wichtiger ist es, die einzelnen Phänomene korrekt und eindeutig zu benennen. Nur so kann man eine saubere Beschreibung der Korrosionsvorgänge erreichen und damit in der wörtlichen und schriftlichen Kommunikation richtig verstanden werden. An zahlreichen Beispielen wird der richtige und normgemäße Sprachgebrauch beschrieben. T2 - Korrosionsschutz in der maritimen Technik CY - Hamburg, Germany DA - 29.01.2020 KW - Korrosion KW - Nomenklatur PY - 2020 AN - OPUS4-50328 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Burkert, Andreas T1 - Korrosionsarten bei nichtrostenden Stählen N2 - Übersichtsvortrag zu Korrosionsarten, die bei nichtrostenden Stählen unter atmosphärischen Bedingungen auftreten können. Theoretische Hintergründe und praktische Beispiel werden für die relevanten Korrosionsarten gezeigt. T2 - VDEh Seminar "Korrosionsverhalten nichtrostender Stähle in wässrigen Medien und bei atmosphärischer Beanspruchung" CY - Düsseldorf, Germany DA - 03.12.2019 KW - Nichtrostender Stahl KW - Korrosion PY - 2019 AN - OPUS4-49945 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Lehmann, Jens T1 - Demonstrationsexperimente N2 - Der Vortrag ergänzt das theroretisch vermittelte Korrosionswissen, macht es mit praktischen Versuchen erlebbar. T2 - VDEh Seminar "Korrosionsverhalten nichtrostender Stähle in wässrigen Medien und bei atmosphärischer Beanspruchung" CY - Düsseldorf, Germany DA - 03.12.2019 KW - Nichtrostender Stahl KW - Korrosion PY - 2019 AN - OPUS4-49947 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Frei, Vivian T1 - Characterizing the Fatigue Behavior of High-Performance Concrete for Wind Energy Structures N2 - Severe mechanical fatigue conditions for worldwide proliferating windfarms are a Major challenge for high-performance concrete in towers, connecting joints and foundations of wind turbines. High-performance concrete offers potential for the application in offshore windfarms, not only regarding its good mechanical, but also chemical resistivity due to low diffusivity in the highly densified microstructure. For a more reliable fatigue assessment, monitoring based on nondestructive testing can be a valuable complement to design rules. Both approaches demand reliable experimental data, information about scalability and the development of standardized testing methods. This article presents results of an ongoing research program of BAM (Bundesanstalt für Materialforschung und -prüfung), which is a part of a joint national project (WinConFat) funded by the German Federal Ministry for Economic Affairs and Energy. The subproject implemented by BAM examines the fatigue behavior in dependence of size and slenderness for varying concrete strength at different stress levels. Besides fatigue strength, nondestructive testing is carried out additionally. Methods used are strain measurement and ultrasonic testing. The change of strain, stiffness and ultrasonic pulse velocity in the fatigue process is discussed. Results disclose a deeper insight into the damage process under cyclic loading of high-performance concrete and contribute to improve nondestructive monitoring. T2 - LORCENIS - Long Lasting Reinforced Concrete for Energy Infrastructue under Severe Operating Conditions CY - Gent, Belgium DA - 10.09.2019 KW - Compressive Cyclic loading KW - Fatigue KW - High-strength concrete KW - Non destructive testing KW - Ultrasonic testing PY - 2019 AN - OPUS4-49474 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Babutzka, Martin T1 - Neue Erkenntnisse zum Korrosionsverhalten von Zink an der Atmosphäre N2 - Die Untersuchungen und Ausführungen im Vortrag belegen, dass verfügbare Modellvorstellungen zur Beschreibung der Deckschichtbildung und Korrosion von Zink unter aktuellen atmosphärischen Bedingungen in Europa nicht mehr gültig sind und neu bewertet werden müssen. So können beispielsweise bisher verfügbare Prognosemodelle den Korrosionsfortschritt nicht mehr ausreichend beschreiben, da durch die Verringerung des Schwefeldioxidgehaltes der Luft veränderte Mechanismen vorliegen. T2 - 69. Sitzung des NA 062-01-71 AA "Korrosion und Korrosionsschutz" CY - Berlin, Germany DA - 27.02.2020 KW - Korrosion KW - Zink KW - Atmosphärische Korrosion KW - Korrosionsprüfung KW - Deckschichtbildung KW - gelartige Elektrolyte PY - 2020 AN - OPUS4-50479 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bäßler, Ralph T1 - Corrosive CO2-stream components, challenging for materials to be used in CC(U)S applications N2 - This contribution provides current findings regarding materials susceptibility for CCUS applications. Basing on results gathered in 2 German long-term projects (COORAL and CLUSTER) suitable materials are introduced as well as dominating impurities of the CO2 stream and corrosion mechanisms. Investigations cover the whole CCUS process chain and provide the following recommendations for certain parts. Commercially available carbon steels are suitable for compression and pipelines as long as moisture content and impurities are limited (water 50 to 100 ppmv, SO2 and NO2 ca. 100 ppmv). Corrosion rates increase with increasing water content (0.2 – 20 mm/a). Condensation of acids and therefore droplet formation is always possible, even at low water contents. A low SO2 content within the CO2-stream might be more important than a low water content. Cr13-steels showed a general susceptibility to shallow pitting and pitting. So, they seem to be not suitable for CCUS applications. Low alloyed steels showed better corrosion behavior (predictable uniform corrosion). For direct contact with saline aquifer fluids only high alloyed steels shall be used. T2 - WCO Webinar on the occasion of Corrosion Awareness Day - Corrosion and Low-Carbon Energies CY - Frankfurt, Germany DA - 24.04.2020 KW - CO2-corrosion KW - CCUS KW - Pipeline KW - Carbon Capture PY - 2020 AN - OPUS4-50699 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Heise, Svenja T1 - Normentwurf für ein Prüfverfahren zur Bestimmung von Deckschichtwiderständen an Zinküberzügen mittels gelartiger Elektrolyte (WIPANO - GELELEK) N2 - Der Vortrag stellt eine Ergebniszusammenfassung des WIPANO-Vorhabens GELELEK im Hinblick auf eine Normung dar. Dafür wird das Projekt zunächst kurz vorgestellt, um anschließend auf normungsrelevante Parameter einzugehen. Dazu gehören insbesondere die Umgebungs- und Messbedingungen, die Herstellungsparameter der Gelpads, das Messverfahren selbst sowie die messbaren Proben. Ein erster Ausblick auf den Normvorschlag wird gegeben. T2 - 14. Sitzung des NA 062-01-77 AA „Korrosionsprüfverfahren“ CY - Berlin, Germany DA - 26.02.2020 KW - Deckschichtbildung KW - Gelartige Elektrolyte KW - Korrosion KW - Korrosionsprüfung KW - Zinküberzüge KW - Atmosphärische Korrosion PY - 2020 AN - OPUS4-50536 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Babutzka, Martin T1 - Beschreibung der Deckschichtbildung bei Zink und Zinklegierungen mittels minimalinvasiver Korrosionsuntersuchungen und analytischer Methoden (MINIMAL) N2 - Der Vortrag stellt ein neuartiges Korrosionsprüfverfahren für Zinküberzüge auf Basis gelartiger Elektrolyte vor und führt die Vorteile gegenüber konventionellen Prüfverfahren auf. Basierend auf den Ergebnissen wird die Idee für einen IGF-Projektantrag in Kooperation mit dem Fraunhofer IKTS vorgestellt. T2 - Web-Meeting GAV-Forschungsbeirat CY - Online meeting DA - 29.04.2020 KW - Deckschichtbildung KW - Zink KW - Korrosionsprüfung KW - Gelartige Elektrolyte PY - 2020 AN - OPUS4-50718 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Metz, Christian T1 - Zerstörungsfreie Charakterisierung additiv gefertigter Kunststoffbauteile und ihres Alterungsverhaltens sowie zerstörende Prüfungen N2 - Es wurden Prüfkörper aus additiver Fertigung mittels Laser Sinter Verfahren (Polyamid 12, PA 12) und Fused Layer Modeling (Acrylnitril-Butadien-Styrol, ABS) sowie Prüfkörper aus dem Kunststoff-Spritzguss Verfahren (PA 12 und ABS) über 2000 Stunden künstlich bewittert. Vor, während und nach der Bewitterung erfolgte eine zerstörungsfreie Prüfung mittels Thermografie, optischer Mikroskopie und spektralen Methoden (UV/VIS-Spektroskopie und spektrale Reflexion), um den Alterungsfortschritt zu untersuchen und Schäden durch die künstliche Bewitterung sowie eingedruckte Defekte zu identifizieren und zu detektieren. Zusätzlich wurden zerstörende Zugprüfungen vorgenommen, welche mit einer IR-Kamera verfolgt wurden. Auf diese Weise konnten lokale Temperaturänderungen, hervorgerufen durch elastische sowie plastische Verformungen, zeitaufgelöst erfasst und ausgewertet werden. T2 - Sitzung des DGM Fachausschusses Polymerwerkstoffe CY - Würzburg, Germany DA - 14.11.2019 KW - Additive Fertigung KW - Thermografie KW - Kunststoffe KW - Zugprüfungen KW - Künstliche Bewitterung PY - 2019 AN - OPUS4-49820 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Erning, Johann Wilhelm T1 - Werkstoffe im Kontakt mit Trinkwasser: Der Weg nach Europa N2 - Die Veränderungen bei der Regulierung der Werkstoffe im Kontakt mit Trinkwasser durch die neue EU-Trinkwasserrichtlinie werden erläutert. Folgen für die etablierten Werkstoffe und Verfahren werden aufgezeigt T2 - DVGW- Bezirksgruppenveranstaltung Berlin/Potsdam CY - Online meeting DA - 15.04.2025 KW - Korrosion KW - Metallmigration KW - Trinkwasser PY - 2025 AN - OPUS4-62985 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Erning, Johann Wilhelm T1 - Metall - Migration in der Trinkwasserinstallation N2 - Der grundsätzliche Mechanismus der Metallmigration wird erläutert, die gesetzlichen Regeln erläutert. Die Veränderungen, die sich aus der neuen EU-Trinkwasserrichtlinie für den Werkstoffeinsatz ergeben, werden erläutert. Beispiele für die Vorgehensweise werden gezeigt, ein Ausblick für die Umsetzung bildet den Abschluss. T2 - 24. Sanitärtechnisches Symposium CY - Ahaus, Germany DA - 04.04.2025 KW - Korrosion KW - Metallmigration KW - Trinkwasser PY - 2025 AN - OPUS4-62900 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Wagner, Adrian T1 - Korrosionsmonitoring bei der Instandsetzung von chloridbelasteten Stahlbetonwerken (KOMICS) N2 - In der aktuellen RL-SIB wie auch im Gelbdruck der Instandhaltungsrichtlinie ist bei Anwendung des Instandsetzungsprinzips W-Cl bzw. Verfahren 8.3 der Erfolg der Maßnahme durch Einbau und Messung von Korrosionsstrom-Mess-Einrichtungen nachzuweisen. Auch wird bei der Instandsetzung von chloridbelasteten Rissen bei Stahlbetonbauteilen durch Verpressen der Risse bzw. Aufbringen einer Rissbandage ein Korrosionsmonitoring empfohlen. Anerkannte Regelwerke oder Normen über Art und Aufbau des Monitoring-Systems sowie Kriterien zur Bewertung der Messergebnisse im Hinblick auf den Erfolg der Instandsetzungsmaßnahme gibt es derzeit nicht. Auch sind keine Untersuchungen zur Qualität der Messergebnisse veröffentlicht. Ziel des Vorhabens ist die Ausarbeitung eines Regelwerks-Entwurfes für die Art und den Aufbau von Korrosionsmonitoring-Systemen sowie für Kriterien zur zuverlässigen Bewertung der Messergebnisse, mit denen der Erfolg bei folgenden Instandsetzungskonzepten überprüft werden kann. T2 - 15. Sitzung des NA 062-01-77 AA "Korrosionsprüfverfahren" CY - Online meeting DA - 28.10.2020 KW - Korrosionsmonitoring KW - Korrosion KW - Korrosionssensoren KW - Chloridinduzierte Lochkorrosion KW - W-Cl Instandsetzungsprinzip PY - 2020 AN - OPUS4-51520 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Le, Quynh Hoa T1 - CO2-stream impurities and their effects on corrosion susceptibility of materials to be used in CCUS systems N2 - Carbon Capture Utilization and Storage (CCUS) is a promising technology to reach the target for reduction of CO2 emissions. Crucial points for a sustainable and future-proof CCUS system are reliability and cost efficiency of the whole process chain, including separation of CO2 from the source, compression of CO2, its subsequent transportation to the injection site and injection into geological formations, e.g. aquifers. Recent studies have shown that even at a very low concentration of impurities, condensation of sulfuric and nitric acids in dense phase CO2 are possible and observable. Thus, impact of impure CO2 stream toward corrosion susceptibility of materials to be used in CCUS system need to be considered. In this talk, basing on results achieved from two German long-term projects (COORAL and CLUSTER), the dominating impurities of the CO2 stream and corrosion mechanisms are addressed. Investigations cover the whole CCUS process chain and provide a material recommendation for certain parts. T2 - Corrosion in Low-Carbon Energies - IFPEN-Lyon CY - Online meeting DA - 03.11.2020 KW - Corrosion KW - CCUS KW - Carbon dioxide PY - 2020 AN - OPUS4-51509 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bäßler, Ralph T1 - Metallic Materials for Geothermal Applications N2 - The aim of the work presented was the evaluation of corrosion resistance of various materials in geothermal Waters as a base to create a catalogue of suitable materials for applications in (not only) German geothermal power plants. Users shall be enabled to have a basis for designing such facilities. High alloyed corrosion resistant alloys are suitable and do not cause copper or lead deposition. They shall be chosen for future design of the piping system, either in massive or in cladded form, if crevices formation with non-metallic materials can be prevented! T2 - IFPEN-Workshop: Corrosion in Low-Carbon Energies CY - Online meeting DA - 03.11.2020 KW - Geothermal KW - Corrosion KW - Saline brine PY - 2020 AN - OPUS4-51511 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Erning, Johann Wilhelm T1 - Wie gehe ich bei einer Schadensuntersuchung vor? N2 - Die Vorgehensweise bei einer Schadensanalyse wird beschrieben. Hinweise zu Methodik, Fehlervermeidung und Verhalten werden gegeben. T2 - Der sichere Einsatz von Werkstoffen aus Kupfer und Kupferlegierungen in der Trinkwasserinstallation CY - Online meeting DA - 21.10.2020 KW - Schadnesanalyse KW - Vorgehensweise KW - Korrosion PY - 2020 AN - OPUS4-51453 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Erning, Johann Wilhelm T1 - Corrosion Problems with 1.4521 steel pipes in drinking water N2 - In several cases crevice corrosion with 1.4521 stainless steel pipes was observed. The presentation shows the investigations that lead to the solution of the failure cases T2 - Eurocorr 2020 CY - Online meeting DA - 07.09.2020 KW - Crevice corrosion KW - Drinking water KW - Stainless steel KW - Failure analysis PY - 2020 AN - OPUS4-51235 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Babutzka, Martin T1 - Auslagerungsversuche von Standardproben nach DIN EN ISO 9223 unter verschiedenen atmosphärischen Bedingungen N2 - Der Vortrag berichtet über die Auslagerung von Standardproben nach DIN EN ISO 9223 bis 9226 aus Zink, Stahl, Kupfer und Aluminium auf den verschiedenen atmosphärischen Bewitterungsständen der Bundesanstalt für Materialforschung und -prüfung (BAM). Im Vortrag werden die Masseverluste, Korrosionsgeschwindigkeiten und Korrosivitätskategorien der Standardproben im freibewitterten und überdachten Bereich nach einem Jahr vorgestellt und Unterschiede hinsichtlich der Atmosphärenbedingungen aufgezeigt. Freibewitterte Proben zeigen dabei deutliche Unterschiede hinsichtlich ihres Korrosionsverhaltens im Vergleich zu überdachten Proben. Die ermittelten Korrosivitätskategorien sind sowohl standort- als auch materialspezifisch. T2 - Gemeinsame Sitzung des GfKORR Arbeitskreises „Korrosionsschutz von Windenergieanlagen“ mit der Fachgruppe „Korrosionsschutz“ der WAB e.V. CY - Online meeting DA - 07.12.2020 KW - Atmosphärische Korrosion KW - Auslagerungsversuche KW - Freibewitterung KW - Korrosion PY - 2020 AN - OPUS4-51783 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Pirskawetz, Stephan A1 - Menningen, J. A1 - Siegesmund, S. ED - Siegesmund, S. ED - Middendorf, B. T1 - Acoustic emissions - Insights into the decay mechanisms of thermally treated marbles N2 - Since ancient times, marble has been the preferred material for monuments, sculptures, Ornaments and architecture. Though the stone is often a Chosen material, long-term exposure of marble results in cumulative deterioration of the rock fabric. The rate and extent of deterioration depends on the rock fabric and the climatic conditions. Besides the thermal vulnerability of marble, a combination of thermal and hygric fluctuation accelerates the deterioration process. The weathering sensitivity of marbles can be characterised by the irreversible length change of samples after heating under thermohygric conditions as residual strain. This residual strain is a non-reversible deterioration and caused by microcracking induced by a pronounced anisotropy of the thermal dilatation coefficient of calcite. In brittle materials like marble, cracking and crack growth or friction on crack surfaces are accompanied by release of acoustic waves. The analysis of these acoustic emissions can give a deeper insight into the deterioration mechanism of marble. In this study, acoustic emissions of thermohygric treated marble were analysed and correlated with ultrasonic velocities, thermal dilatation and residual strains. Therefore, different types of calcitic marble were cyclically heated from 20 °C to 90 °C and after equilibration of the samples cooled down again to 20 °C. While the first cycles were performed under dry conditions, the following were executed in a humid environment. The analysis of acoustic emissions enables one to determine when cracking occurs during the thermal treatment. It is also possible to differentiate microcracking from internal friction. Furthermore, the evolution of Deterioration can be estimated based on ultrasonic velocities. The combination of acoustic Methods and strain measurement gives an insight into the disintegration mechanism and Supports the development of prevention strategies. T2 - 14th International Congress on the Deterioration and Conservation of Stone CY - Göttingen, Germany DA - 07.09.2020 KW - Marble KW - Weathering sensitivity KW - Cracking KW - Acoustic emission KW - Residual strain PY - 2020 SN - 978-3-96311-172-3 SP - 185 EP - 190 PB - mdv Mitteldeutscher Verlag GmbH CY - Halle (Saale) AN - OPUS4-51964 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Eiz Eddin, Ahmad T1 - Zum Feuerwiderstand von filigranen Deckenelementen aus vorgespanntem Carbonbeton N2 - Der Einsatz von hoch zugbeanspruchbarem und korrosionsbeständigem Carbongelege anstelle von herkömmlichem Spannstahl ermöglicht es Beton vorzuspannen und gleichzeitig die Betondeckung auf ein für den Verbund nötiges Minimum zu reduzieren. Das Carbongelege besteht aus Carbonfasern in einer Kunststoffmatrix. Mit dieser Bauweise können dünnwandige und damit ressourcenschonende Deckenelemente realisiert werden. Der Wechsel von massiven zu filigranen und vergleichsweise leichten Bauteilen führt jedoch aufgrund der geringeren Masse und der damit einhergehenden schnelleren Erwärmung zu einer Abnahme des Feuerwiderstands. Ferner führt die Erweichung der Matrix im Brandfall zu einer Abnahme der Verbundfestigkeit zwischen Carbongelege und Beton. Die Brennbarkeit des Carbongeleges sowie die Abplatzneigung des verwendeten Feinbetons stellen weitere Herausforderungen für den baulichen Brandschutz dar. Der Beitrag stellt Versuchsergebnisse zum Abplatz- und Hochtemperaturverhalten von Carbonbeton vor, die im Rahmen des Verbundvorhabens „Vorgespannte Carbonbetondecken mit reduzierten Querschnitten“ (CaPreFloor) erzielt wurden. Für die Untersuchung der Tragfähigkeit bei hohen Temperaturen wurden 4-Punkt-Biegeversuche an balkenförmigen Prüfkörpern (150 x 30 x 6 cm³) mit einlagiger Carbonbewehrung und instationärer Temperaturbeanspruchung durchgeführt. Neben dem Vorspanngrad des Carbongeleges wurde auch der Gelegetyp variiert. Im Bereich der konstanten Biegezugzone erfolgt die einseitige Erwärmung mittels elektrisch betriebener Heizmatten. Während der kontinuierlichen Erwärmung werden die Prüfkörper mit einer konstanten Kraft belastet, deren Betrag aus zuvor durchgeführten Biegeversuchen bei Raumtemperatur abgeleitet wurde. Die Abplatzversuche werden mit Einheits-Temperaturzeitkurve an rechteckigen (60 x 60 x 6 cm³) und kreisrunden (Ø 47 x 6 cm³), plattenförmigen Prüfkörpern am 1m³-Ofen der BAM durchgeführt. Die kreisrunden Prüfkörper sind zusätzlich mit einem Stahlring zur Behinderung der thermischen Dehnung des Betons versehen. Um den Einfluss des Geleges auf das Abplatzverhalten zu analysieren, werden sowohl Prüfkörper mit Carbongelege als auch unbewehrte Prüfkörper untersucht. Die daraus resultierenden Erkenntnisse fließen in die weitere Entwicklung der vorgespannten Carbonbetondeckenelemente ein. Anhand von realmaßstäblichen Brandversuchen wird der Feuerwiderstand dieser Bauteile im weiteren Projektverlauf bestimmt. T2 - Symposium Heißbemessung 2024 CY - Braunschweig, Germany DA - 24.09.2024 KW - Carbonbeton KW - Feuerwiderstand KW - Brandversuch KW - Carbon KW - Material PY - 2024 AN - OPUS4-61125 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Wiehle, Philipp A1 - Härder, M. A1 - Strangfeld, Christoph T1 - Feuchteverhalten von Lehmsteinmauerwerk unter natürlichen Klimabedingungen – Experimentelle und numerische Untersuchungen N2 - Druckfestigkeit und Elastizitätsmodul von Lehmsteinmauerwerk nehmen mit steigendem Feuchtegehalt ab, weswegen die Mauerwerksdruckfestigkeit bei der Bemessung gemäß DIN 18940 in Abhängigkeit der maximal zu erwartenden Ausgleichsfeuchte abgemindert wird. Da bisher allerdings keine Messdaten zum Feuchtegehalt von Lehmsteinmauerwerk unter natürlichen Klimabedingungen vorliegen, stellen die normativen Grenzwerte lediglich eine konservative Abschätzung dar. Um die Feuchtegehalte von Lehmsteinmauerwerk und somit die Tragfähigkeit realitätsnah einschätzen zu können, wurden im Rahmen der vorliegenden Arbeit sowohl experimentelle als auch numerische Untersuchungen zum feuchtetechnischen Verhalten durchgeführt. Dabei wurden erstmalig magnetresonanzspektroskopische Untersuchungen an tragenden Lehmsteinen unterschiedlicher Herstellungsmethoden angewandt Weiterhin wurden Luftfeuchtesensoren in Lehmsteinmauerwerk eingebettet, um hygrische Langzeitfeuchtemessungen unter natürlichen Klimabedingungen durchzuführen. Auf Basis dieser Erkenntnisse wurde schließlich ein numerisches Modell kalibriert und Parameterstudien durchgeführt, um den unter realen Klimabedingungen tatsächlich auftretenden Feuchtegehalt im Lehmmauerwerk sowie dessen Verteilung über den Querschnitt einschätzen zu können und die normativen Grenzwerte zu überprüfen. Gezeigt wurde, dass die realitätsnahe instationäre Berechnung des Feuchtetransports mit üblichen hygrothermischen Simulationsprogrammen auf Basis einfacher feuchtetechnischer Kennwerte auch bei Lehmbaustoffen möglich ist. Der Einfluss des Quellens und Schwindens der enthaltenen Tonminerale und organischen Bestandteile wurde durch eine Modifikation bei der Ermittlung des Wasseraufnahmekoeffizienten explizit berücksichtigt und ist somit auch in den daraus abgeleiteten Transportkoeffizienten enthalten. Darüber hinaus wurde die Feuchtespeicherfunktion im überhygroskopischen Bereich auf Grundlage der Porenvolumenverteilung abgeschätzt. Die Approximation der Transportkoeffizienten und der Feuchtespeicherfunktion stellt dabei eine wesentliche Vereinfachung für Lehmbaustoffe dar, da ihre experimentelle Bestimmung aufgrund des Kontaktes mit Flüssigwasser kaum möglich ist. In Bezug auf das Feuchteverhalten üblicher Außenwandaufbauten von Wohnräumen konnte festgestellt werden, dass die Ausgleichsfeuchte im Lehmsteinmauerwerk stets unterhalb des in Nutzungsklasse 1 gemäß DIN 18940 zulässigen Grenzwertes von 65 % liegt. Je nach Putzsystem und Dämmstoff reduziert sich die Ausgleichsfeuchte auf Werte unter 60 %, wobei sich eine annähernd gleichmäßige Verteilung der Feuchte über den Mauerwerksquerschnitt hinweg einstellt. Bei Außenwänden von unbeheizten Räumen ergab sich eine maximale Ausgleichsfeuchte, die über weite Teile des Querschnitts unterhalb von 80 % lag. Der Ansatz einer maximalen Ausgleichsfeuchte von 90 % in Nutzungsklasse 2 ist folglich zu hoch angesetzt. Die zulässige Ausgleichsfeuchte bzw. der Umgebungsfeuchtefaktor in Nutzungsklasse 2 sollte dementsprechend angepasst werden T2 - LEHM 2024 – 9. Internationale Fachtagung für Lehmbau CY - Weimar, Germany DA - 27.09.2024 KW - Lehmstein KW - Mauerwerk KW - Materialfeuchte KW - Feuchtemonitoring KW - hygrothermische Simulation PY - 2024 SP - 1 EP - 10 AN - OPUS4-61217 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Schmidt, S. A1 - Pirskawetz, Stephan T1 - Monitoring mit Schallemissionsmessung N2 - Die Brücke am Altstädter Bahnhof in Brandenburg an der Havel stand bei ihrer Eröffnung im Jahr 1969 für die höchste Ingenieurskunst der damaligen Zeit und für einen in die Zukunft gerichteten Blick. Sie trug den Namen "Brücke des 20. Jahrestag", denn am 20. Jahrestag der DDR wurde die Brücke für den Verkehr freigegeben. Sie verbindet die westlichen Stadtbezirke mit dem Zentrum der Stadt Brandenburg an der Havel und wurde so von vielen Einwohner:innen genutzt. Zu Fuß, mit dem Rad, dem Auto oder mit der Straßenbahn. 50 Jahre später, im Dezember 2019, wurde bei einer Bauwerksprüfung eine starke Schadenszunahme festgestellt. Eine sofortige Sperrung für den Verkehr war unumgänglich. Das hatte es im Land Brandenburg bislang nicht gegeben und stellt einen einzigartigen Sonderfall bei der Bewertung von Bauwerken dar. Die Sperrung führte zu starken Einschränkungen für den Verkehr, für den Landesbetrieb Straßenwesen aber hatte die Sicherheit oberste Priorität. Um die Belastung für die Stadt so gering wie möglich zu halten, hat der Landesbetrieb Straßenwesen sofort mit der Planung für Abriss und Neubau der Brücke begonnen. So gelang es innerhalb von kurzer Zeit den Rückbau umzusetzen und die Pläne für den Ersatzneubau vorzustellen. Gleichzeitig bot sich die einmalige Gelegenheit, kurz vor dem Rückbau noch umfangreiche Untersuchungen zur Verifizierung des Schadensbilds durchzuführen und verschiedene Monitoringverfahren zum Einsatz zu bringen. Damit wurden wertvolle Erfahrungen gesammelt, die der Landesbetrieb Straßenwesen anderen Baulastträgern zur Verfügung stellen möchte. Sie ermöglichen es, bei baugleichen Bauwerken zielgerichteter handeln zu können. Die Fülle der untersuchten Aspekte ist in diesem Bericht dokumentiert. Diese umfangreichen Untersuchungen wurden vom Bundesministerium für Verkehr und digitale Infrastruktur finanziert. Dafür möchten wir uns herzlich bedanken. Mit großem Engagement digitabeteiligt haben sich auch die Bundesanstalt für Materialforschung und -prüfung, die Technische Universität Dresden, die Hochschule für Wirtschaft und Technik Dresden sowie das Unternehmen Bilfinger Noell und die Ingenieursozietät Zech, Ruth, Blasius. Auch bei Ihnen bedankt sich der Landesbetrieb Straßenwesen. KW - Baustoffe KW - Korrosion KW - Beton KW - Spannbeton KW - Brücke KW - Spannstahl KW - Spannungsrisskorrosion KW - Zerstörungsfreie Prüfung KW - Schallemissionsanlayse KW - Spanndrahtbruch PY - 2021 SP - 65 EP - 71 PB - Landesbetrieb Straßenwesen Brandenburg CY - Hoppegarten AN - OPUS4-54600 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kühne, Hans-Carsten T1 - Die Kandelaber des Ensembles am Charlottenburger Tor N2 - Auf der Charlottenburger Brücke entstand mit dem Charlottenburger Tor und den beiden Kandelabern von 1905 bis 1908 ein repräsentatives Ensemble von Einzelbauwerken. Für die architektonische Wirkung des Charlottenburger Tores waren die beiden ca. 22 Meter hohen Kandelaber auf der Charlottenburg zugewandten Seite des Tores bedeutsam. Die Stiftung Denkmal ließ die Kandelaber seit Mai 2007 mit dem Ziel rekonstruieren, dem Tor, seiner Umgebung und der Straße des 17 Juni den historischen Gesamteindruck wiederzugeben. Im Rahmen der Rekonstruktion wurde die Grundsatzentscheidung getroffen, dass die Wiederherstellung der komplett zerstörten und auch nicht mehr in Fragmenten vorhandenen Kandelaber nicht unter Anwendung der Bautechnik von 1900 durchgeführt werden sollte. Die Zielsetzung war viel mehr, mit moderner Bautechnik die Anmutung der Kandelaber von 1903 wiederherzustellen, die in Verbindung mit anderen baulichen Elementen, wie der Charlottenburger Brücke und des Charlottenburger Tores, den historischen Gesamtkomplex bilden. T2 - Workshop Kulturguterhaltung - Vom Dampfkessel zu Nanomaterialien CY - Berlin, Germany DA - 17.11.2021 KW - Charlottenburger Tor KW - Kunststein KW - Hydrophobierung KW - Bildhauerbeton PY - 2021 VL - 3 SP - 97 EP - 105 PB - Druckerei G. Bohm CY - Berlin AN - OPUS4-57091 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Titscher, Thomas T1 - High-order cycle jump integration of a concrete fatigue damage model N2 - Fatigue models that accurately resolve the complex three-dimensional failure mechanisms of concrete are numerically expensive. Especially the calibration of fatigue parameters to existing Wöhler lines requires solving for thousands or millions of cycles and a naive cycle-by-cycle integration is not feasible. The proposed adaptive cycle jump methods provide a remedy to this challenge. They greatly reduce the numerical effort of fatigue simulations and provide the basis for a development of those models. T2 - 8th GACM Colloquium on Computational Mechanics CY - Kassel, Germany DA - 28.08.2019 KW - Time scale separation KW - Cycle jump KW - Fatigue damage PY - 2019 AN - OPUS4-52191 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Vogler, Nico A1 - Lindemann, Mathias A1 - Drabetzki, Philipp A1 - Kühne, Hans-Carsten T1 - Alternative pH-indicators for determination of carbonation depth on cement-based concretes N2 - The most common method for determination of the carbonation depth is the sprayed application of indicator solutions, Phenolphthalein in particular. Since the aerosols of Phenolphthalein are suspected to be carcinogenic, efforts have been intensified to use alternative indicators for the determination of carbonation depth. The subject and aim of this research paper are to examine indicator solutions from Alizarin Yellow R, Thymol Blue and a Mixed Indicator. These indicator solutions are commercially available and are not suspected to be carcinogenic. For the purpose of this research, samples previously stored under accelerated carbonation conditions (1% CO2) were examined by thermogravimetric analysis (TGA) and examination of the pH value. Additionally, the electrolytic back-titration for determination of total CO2 amount was carried out comparatively to TGA. KW - Thermal analysis KW - Accelerated carbonation KW - pH-indicators KW - Concrete PY - 2020 DO - https://doi.org/10.1016/j.cemconcomp.2020.103565 VL - 109 SP - 1 EP - 9 PB - Elsevier Ltd. AN - OPUS4-50458 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Voigt, Marieke A1 - Gardei, Andre A1 - Meng, Birgit ED - di Prisco, M. ED - Meda, A. ED - Balazs, G.L. T1 - The adaption of the set-up for gas permeability measurements for ultra-high performance concrete N2 - In the framework of this project, a steam pressure vessel was to be developed from ultra-high perfor-mance concrete (UHPC) to withstand process temperatures of 200 °C and the respective steam pressure of 15,5 bar. To guarantee the long-term water vapour tightness of the system, the permeability of two UHPC mixtures were tested after long-term cyclic autoclaving. As UPHC shows a high density and therefore low permeability, measurements after the RILEM-Recommendation (TC 116-PCD) reached their detection limit. Therefore, the measurement set-up was adapted to measure the permeability of highly dense UHPC more reliably and quickly. This adaption includes measurements in a higher pres-sure range, the change of sample size thickness and the usage of Ar as a medium compared with the RILEM Recommendation. Additionally, the system was equipped with two pressure sensors and Ar-flowmeters to guarantee a continuous record of the experimental parameters. The new system was tested and evaluated by comparing measurements with the RILEM recommended system. Preliminary results show that the adapted system is capable to provide efficient and reliable results of concrete with low permeability. T2 - 14th fib PhD Symposium in Civil Engineering CY - Rom, Italy DA - 05.09.2022 KW - Durability KW - UHPC KW - gas permeability PY - 2022 SN - 978-2-940643-17-2 SN - 2617-4820 VL - 58 SP - 353 EP - 359 AN - OPUS4-56862 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Seher, Julia T1 - Hydrothermalgranulate - Verwertungsmöglichkeit für gemischten Mauerwerkbruch und Papierasche N2 - Jährlich fallen in Deutschland ca. 56 Mio. t mineralischer Bauschutt an, der eine vielfältig einsetzbare sekundäre Rohstoffquelle darstellt. Trotz hoher Verwertungsquoten werden Bau- und Abbruchabfälle zum Teil deponiert, weil geeignete und rentable Verwertungswege fehlen. Der Reststoff Mauerwerkbruch ist ein heterogenes SiO2-reiches Gemisch aus Ziegel, Beton- und Leichtbetonsteinen, Kalksandstein, Porenbeton, Putz und Mörtel. Die un-einheitliche Zusammensetzung und mehr als 50 % Feinanteile durch die mechanische Aufbereitung verhindern meist eine unmittelbare Wiederverwertung als RC-Gemisch. Eine Möglichkeit der effektiven Verwertung von Mauerwerkbruchmehlen stellt das rohstoffliche Recycling über einen hydrothermalen Stoffumwandlungsprozess dar, bei dem poröse Granulate entstehen. Aus den Granulateigenschaften, insbesondere der Porenstruktur, ergeben sich Anwendungen als Filter- oder Speichermaterial, d. h. auch in Bereichen, die über den Bausektor hinausgehen. Hierbei können die Granulate leichte Gesteinskörnungen natürlichen Ursprungs, z. B. Lavasand oder Blähtone, ersetzen und somit einen Beitrag zur Schonung natürlicher Ressourcen leisten. Im Fokus des aktuellen ZIM-Projekts HYTEGRA steht die Entwicklung eines solchen hydrothermalen Herstellungsprozesses und die umfassende Charakterisierung der hergestellten Hydrothermalgranulate. Als sekundäre Rohstoffquelle wird neben SiO2-reichem Mauerwerkbruch aus Bau- und Abbruchabfällen auch CaO-reiche Papierasche eingesetzt. Die-se Asche aus dem Altpapierrecycling weist ebenfalls ein erhebliches Verwertungsdefizit auf. Ihr Freikalk ermöglicht den Einsatz als Kalksubstitut. Die Herstellung der Hydrothermalgranulate erfolgt in einem mehrstufigen mechanischen Prozess mit abschließender hydrothermaler Behandlung. Das konventionell mechanisch aufbereitete Abbruchmaterial (RC-Gemisch < 32 mm) wird mittels Kugelmühle zu einem Mehl (< 120 µm) verarbeitet, welches im Intensivmischer unter Zugabe von Kalk und Wasser granuliert wird. Die Härtung der Grüngranulate erfolgt hydrothermal unter erhöhtem Druck in gesättigter Wasserdampfatmosphäre bei Temperaturen von etwa 200 °C. Während des Härtungsprozesses bilden sich aus Quarz (SiO2), Kalk (CaO) und Wasser Calciumsilicathydrat-Phasen, die für die benötigte Festigkeit und Porosität der Hydrothermalgranulate sorgen. Durch die Variation der Syntheseparameter Temperatur, Druck, Zeit und SiO2-CaO-Mischungsverhältnis während der hydrothermalen Härtung, aber auch durch die Prozessführung der Granulierung, wird die Variation und gezielte Einstellung der Eigenschaften der Hydrothermalgranulate ermöglicht. In Kooperation mit Industriepartnern werden die hergestellten Hydrothermalgranulate in verschiedenen Applikationsbereichen getestet, z.B. in Bodenfiltern zur Abwasserbehandlung sowie als temporärer Wasserspeicher zur inneren Nachbehandlung von hochfestem Beton und in Pflanzsubstraten. Im Tagungsbeitrag wird das Projekt HYTEGRA vorgestellt, insbesondere der hydrothermale Verwertungsweg unter Verwendung von Mauerwerkbruch und Papierasche im Labor- und Technikumsmaßstab sowie die Anwendung der hergestellten porösen Granulate als Filter- und Speichermaterial. T2 - Tagung "Aufbereitung und Recycling" 2020 CY - Online meeting DA - 12.11.2020 KW - Mauerwerkbruch KW - Papierasche KW - Rohstoffliches Recycling KW - Poröse Granulate PY - 2020 AN - OPUS4-51560 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Simon, Patrick T1 - Zustandsbewertung von Bauwerken unter veränderlichen Umgebungsbedingungen mittels Structural Health Monitoring N2 - Brücken sind Teil der alternden Verkehrsinfrastruktur. Um die Nutzungsdauer zu verlängern und plötzliche Schäden zu detektieren kann Bauwerksmonitoring ("Structural Health Monitoring") eingesetzt werden. Der Einfluss von Umgebungsbedingungen, beispielsweise der Temperatur, auf das Bauwerksverhalten ist meist größer als der Einfluss von Schäden. Diese Einflüsse bestmöglich voneinander zu trennen und Veränderungen im Tragverhalten korrekt Schäden oder Umgebungsbedingungen zuzuordnen ist eine offene Forschungsfrage. Diese Arbeit zeigt eine mögliche Lösung, bei der gekoppelte Modelle von Umwelteinflüssen, Schäden und Tragverhalten des Bauwerks auf Grundlage von Monitoringdaten aktualisiert werden. Das Framework dazu wird vorgestellt und an einem Laborexperiment eines Stahlbetonbalkens in der Klimakammer angewandt. Die Ergebnisse bestätigen die Vorgehensweise. In nächsten Schritten müssen komplexere Tragwerke und die Sensitivität des Ansatzes untersucht werden. T2 - Forschungskolloquium, Institut für Konstruktiven Ingenieurbau, Bauhaus-Universität Weimar CY - Weimar, Germany DA - 28.06.2023 KW - Structural health monitoring KW - Bauwerksmonitoring KW - Umwelteinflüsse KW - Brücken PY - 2023 AN - OPUS4-58005 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Recknagel, Christoph A1 - Hoppe, Johannes A1 - Eilers, M. T1 - Zusätzliche Technische Vertragsbedingungen und Richtlinien für Ingenieurbauten, Teil 7: Brückenbeläge, Abschnitt 1: Brückenbeläge auf Beton mit einer Dichtungsschicht aus einer Polymerbitumen-Schweißbahn N2 - Die Forschungsgesellschaft für Straßen- und Verkehrswesen hat den „Abschnitt 1: Brückenbeläge auf Beton mit einer Dichtungsschicht aus einer Polymerbitumen-Schweißbahn“ zu dem Teil 7: „Brückenbeläge“ der ZTV-ING überarbeitet und neu herausgegeben. Die Neuausgabe berücksichtigt die aktuellen Anforderungen durch die Europäische Normung bezüglich der Polymerbitumen-Schweißbahnen. Weitere Änderungen zur Vorgängerausgabe von 2003 wurden notwendig durch die Neuauflagen weiterer FGSV-Regelwerke, insbesondere der TL Bitumen-StB (FGSV 794), der ZTV Fug-StB (FGSV 897/1), der TL Fug-StB (FGSV 897/2), der TP Asphalt-StB (FGSV 756) und der E KvB (FGSV 727). Die ZTV-ING Teil 7 Abschnitt 1 führt insbesondere aus zu den Grundlagen des Brückenbelages, zur Ausführung und Qualitätssicherung sowie zur Herstellung unmittelbar auf Trog- und Tunnelsohlen aus Beton. Der Anhang enthält die „Vorgaben für die Prüfungen während der Bauausführung“ sowie das Formblatt „Protokoll über die Entnahme von Rückstellproben“ und eine tabellarische Zusammenstellung über „Art und Umfang sowie Anforderungen und Toleranzen für die Baustoffeinangsprüfungen“. Das Bundesverkehrsministerium hat mit seinem ARS 23/2021 zur Fortschreibung der ZTV-ING die Neuausgabe der Teils 7 Abschnitt 1 bekannt gemacht. Die „Zusätzlichen Technischen Vertragsbedingungen und Richtlinien für Ingenieurbauten, Teil 7: Brückenbeläge, Abschnitt 1: Brückenbeläge auf Beton mit einer Dichtungsschicht aus einer Polymerbitumen-Schweißbahn“, Ausgabe 2021 ersetzen die „Zusätzlichen Technischen Vertragsbedingungen und Richtlinien für Ingenieurbauten, Teil 7: Brückenbeläge, Abschnitt 1: Brückenbeläge auf Beton mit einer Dichtungsschicht aus einer Bitumen-Schweißbahn“, Ausgabe 2003. KW - Brückenbeläge KW - Asphaltbauweise KW - PmB Schweißbahn KW - Technische Anforderungen PY - 2022 SN - 978-3-86446-323-5 VL - 782/2 SP - 1 EP - 31 PB - FGSV Verlag GmbH CY - Köln AN - OPUS4-54859 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Stohl, Leonie T1 - Bioreceptivity of structured concrete panels N2 - Understanding the fundamentals of bioreceptivity enables the developement of functionalized materials. Concrete as the most used building material worldwide is of special interest as microbially greened panels may represent an alternative to classic façade greening with plants. � This project includes extensive outdoor experiments, in which eight differently structured concrete panels are weathered under different conditions, aiming to grow a stable biofilm of photosynthetic eukaryotic organisms. Documentation and data analysis of this experiment will be demonstrated using an example of one of the surfaces. T2 - Word Green Infrastructure Congress 2023 CY - Berlin, Germany DA - 27.06.2023 KW - Bioreceptivity KW - Concrete KW - Material design PY - 2023 AN - OPUS4-57919 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CHAP A1 - Gehlen, C. A1 - Kränkel, T. A1 - Meng, Birgit A1 - Osterminski, K. A1 - Meyer, F. A1 - Schröder, P. ED - Zilch, K. T1 - Baustoffe im Betonbau N2 - In dem Kap. „Baustoffe im Betonbau“ werden zunächst die Baustoffe vorgestellt, die für die Herstellung von Stahlbeton- und Spannbetonbauwerken erforderlich sind (im Wesentlichen Beton, Betonstahl und Spannstahl). Herstellungsbedingte, typische Eigenschaftsprofile der Baustoffe werden aufgezeigt und ein Bezug zu entsprechenden Anwendungsgebieten hergestellt. KW - Betontechnik KW - Bindemittel KW - Betonstahl KW - Spannstahl KW - Herstellungsprozesse KW - Eigenschaften KW - Anwendungsbeispiele PY - 2019 SN - 978-3-658-21749-5 DO - https://doi.org/10.1007/978-3-658-21749-5_15-1 SP - 1 EP - 63 PB - Springer Fachmedien Wiesbaden GmbH AN - OPUS4-54173 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Radenberg, M. A1 - Schwettmann, K. A1 - Weigel, Sandra T1 - Möglichkeiten der vollständigen oder teilweisen Substitution von Bitumen als Bindemittel im Asphaltstraßenbau N2 - Die Klimakrise sowie die damit verbundene Distanzierung vom Erdöl und die aktuelle geopolitische Situation in Europa erfordern, dass die Asphaltbranche sowohl lang- als auch kurzfristig einen erdölunabhängigen Weg einschlägt. Langfristig sollte dabei ein vollständiger Ersatz des Bitumens durch biobasierte, nachhaltige Alternativmaterialien erfolgen, während kurz- bzw. mittelfristig ein teilweiser Ersatz bzw. eine Wiederverwendung von Asphalt mit biobasierten Alternativmaterialien eine Reduzierung der Erdölabhängigkeit erlauben würden. In diesem Zusammenhang wurden in dem Projekt „Möglichkeiten der vollständigen oder teilweisen Substitution von Bitumen als Bindemittel im Asphaltstraßenbau“ in einer umfassenden Literaturrecherche Erfolg versprechende Alternativbindemittel zur Bitumensubstitution und Bindemittelverjüngung identifiziert. Eine vielversprechende Eignung zeigen dabei vor allem verschiedene auf pflanzlicher Biomasse basierende Materialien (z. B. Lignine in Kombination mit öligen Komponenten, Bioöle, Zuckerrohrmelasse/-bagasse), aber auch Produkte basierend auf tierischer Biomasse (z. B. aufbereitete Schweinegülle), aquatischer Biomasse (z. B. Rückstände der Mikroalgenaufbereitung) oder aus Abfällen (z. B. gebrauchtes Speiseöl). N2 - The climate crisis with the increasing distancing from crude oil and the current geopolitical situation in Europe require the asphalt industry to take a path that is independent of crude oil in both the long and short term. In the long term, bitumen should be completely replaced by bio-based, sustainable alternative materials, while in the short and medium term, partial replacement, or reuse of asphalt with bio-based alternative materials for rejuvenation would reduce dependence on oil. In this context, the project “Possibilities for the total or partial substitution of bitumen as a binder in asphalt road construction” identifi ed promising alternative binders for bitumen substitution and binder rejuvenation in a comprehensive literature review. The most promising suitability is shown by various materials based on plant biomass (e. g. lignins in combination with oily components, bio-oils, sugar cane molasses/bagasse, but also products based on animal biomass (e. g. processed swine manure), aquatic biomass (e. g. residues from microalgae processing) or from waste (e. g. waste cooking oil). KW - Nachhaltiger Asphaltstraßenbau KW - Teilweise und vollständige Bitumensubstitution KW - Asphaltwiederverwendung KW - Pflanzliche Biomasse KW - Tierische Biomasse KW - Meeresbiomasse KW - Abfälle PY - 2024 DO - https://doi.org/10.53184/STA10-2024-2 IS - 11 SP - 896 EP - 901 PB - Kirschbaum Verlag AN - OPUS4-62099 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CHAP A1 - Brinkmann, M. A1 - Wiehle, Philipp A1 - Thiele, Marc A1 - Graubner, C.-A. ED - Schermer, D. ED - Brehm, E. T1 - Grundlagen zur Bemessung druckbeanspruchten Lehmmauerwerks N2 - Lehmmauerwerk bietet sich aufgrund seiner zahlreichen ökologischen Vorteile für die Errichtung klimafreundlicher und ressourcenschonender Gebäude an. Um den Anwendungsbereich tragenden Lehmmauerwerks durch eine zeitgemäße Nachweisführung zu erweitern, werden in diesem Beitrag Grundlagen für die Entwicklung eines eurocodekonformen Bemessungskonzepts erarbeitet. Hierzu werden die Ergebnisse umfangreicher experimenteller Untersuchungen an Lehmmauerwerk sowie Lehmsteinen und -mörteln nach Konditionierung bei unterschiedlichen Klimata vorgestellt. Darauf aufbauend erfolgt eine Traglastanalyse druckbeanspruchter Lehmmauerwerkswände mittels numerischer und analytischer Methoden. Die daraus gewonnenen Erkenntnisse werden abschließend in einen an DIN~EN~1996-3/NA angelehnten Bemessungsvorschlag überführt, welcher die materialspezifischen Besonderheiten von Lehmmauerwerk berücksichtigt und eine fundierte Grundlage für eine wirtschaftliche und zuverlässige Nachweisführung darstellt. KW - Druckfestigkeit KW - Lehm KW - Mauerwerk KW - Bemessung KW - Feuchte PY - 2023 SN - 978-3-433-03373-9 DO - https://doi.org/10.1002/9783433611142.ch4 VL - 48 SP - 79 EP - 110 PB - Ernst & Sohn GmbH CY - Berlin ET - 1 AN - OPUS4-57509 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rübner, Katrin T1 - Vom Bauschutt zur leichten Gesteinskörnung N2 - Leichte Gesteinskörnungen können ressourcenschonend aus heterogenen und feinkörnigen Bau- und Abbruchabfällen in einem mehrstufigen Prozess durch thermische oder hydrothermale Stoffumwandlung hergestellt werden. Ihre Anwendung erfolgt in Leichtbetonen und Leichtmörteln, als Schüttung im Garten und Landschaftsbau oder auch als Filter- und Speichermaterial. In zahlreichen Forschungsprojekten wurden die Herstellungsprozesse entwickelt, die Materialeigenschaften optimiert und unterschiedliche Applikationen untersucht. In diesem Beitrag wird zusammenfassend über dieser Forschungsarbeiten berichtet. T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM Green Intelligent Building CY - Berlin, Germany DA - 16.10.2024 KW - Bauschutt KW - Leichte Gesteinskörnung KW - Mauerwerkbruch KW - Hydrothermalgranulat PY - 2024 AN - OPUS4-61741 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bednarska, Dalia T1 - Modification of clay-based materials with a novel geopolymer: potential application towards water-resistance N2 - Earth is probably the most eco-friendly building material. However, since earthen materials dissolve in water easily their application is limited. The presented manuscript aims to verify the usefulness of a one-part geopolymer developed at BAM as a stabilizing agent for earthen mortars. The experimental study encompasses water-resistance, compressive strength, linear shrinkage, water vapour permeability and microstructural analysis of the reference and the modified earthen plaster. The presented results show that the modification visibly affects the properties of the initial material providing its water-resistance. T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM Green Intelligent Building CY - Berlin, Germany DA - 16.10.2024 KW - Clay-based Material KW - Water-Resistance KW - Mortar KW - Geopolymer KW - Calcined clay KW - Biomass ash KW - Paper ash PY - 2024 AN - OPUS4-61822 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Strobl, Domninic T1 - PGD in thermal transient problems with a moving heat source – a sensitivity study on factors affecting accuracy and efficiency N2 - Thermal transient problems, essential in applications like welding and additive metal manufacturing, are characterized by a dynamic evolution of temperature. Accurately simulating these phenomena is often computationally expensive, thus limiting the application, e. g. for model parameter estimation or online process control. Model order reduction, a solution to preserve accuracy while reducing complexity, is explored. This paper addresses challenges in developing a reduced model using the Proper Generalized Decomposition (PGD) for transient thermal problems with a specific treatment of the moving heat source within the reduced model. Factors affecting accuracy, convergence, and computational cost, such as discretization methods (finite element and finite difference), a dimensionless formulation, the size of the heat source, and the inclusion of material parameters as additional PGD variables are examined across progressively complex examples. The results demonstrate the influence of these factors on the PGD model's performance and emphasize the importance of their consideration when implementing such models. For thermal examples it is demonstrated that a PGD model with a finite difference discretization in time, a dimensionless representation, a mapping for a moving heat source, and a spatial domain non-separation yields the best approximation to the full order model. KW - Additive manufacturing KW - Mapping for unseparable load KW - Model order reduction KW - Proper generalized decomposition KW - Sensitivity analysis KW - Thermal transient problem PY - 2024 DO - https://doi.org/10.5281/zenodo.10102489 PB - Zenodo CY - Geneva AN - OPUS4-62235 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Manninger, T. A1 - von Werder, Julia A1 - Rübner, Katrin T1 - Lehmstabilisierung mittels eines Biomasseasche basierten Alkali-Aktivators und kalziniertem Ton N2 - Lehm sowie Lehmziegel sind jahrtausendealte Baustoffe, die sich durch lokale Verfügbarkeit, Umweltverträglichkeit und geringe COa-Belastung auszeichnen. Diese Eigenschaften machen sie zu Baustoffen der Zukunft. Wasserbeständigkeit ist ein wichtiger Aspekt, der beim Einsatz beachtet werden muss. Es gibt verschiedene Ansätze zur Stabilisierung, Idealerwelse sollen dabei die positiven Aspekte des Lehms, wie beispielsweise die Luftfeuchteregullerung, bewahrt werden. Zement ist hierfür nur bedingt geeignet. Als Alternative zur Stabilisierung mit Zement wurden in einer Versuchsreihe Mischungen mit calclnierten Tonen untersucht. Diese bei 600 °C auf CO2 sparende Welse erzeugten, lokal verfügbaren Rohstoffe, können mittels Alkall-Aktivierung zu einem festen „Geopolymer" vernetzt werden. Zur Aktivierung wurde eine lokal verfügbare Biomasseasche aus Hackschnitzelholz, sowie Industriell hergestelltes KOH genutzt, da das in beiden enthaltene Kalium das umweltverträglichste Alkallion Ist. In einer Versuchsreihe wurde das Verhalten des reinen Lehms mit dem stabilisierten Material verglichen. Es wurden Festigkeitswerte, Wasserlagerungsbeständigkeit und Wasserdampfdiffusionswiderstand geprüft. T2 - Internationale Baustofftagung (ibausil) CY - Weimar, Germany DA - 13.09.2023 KW - Lehmstabilisierung KW - Alkali aktivierte Bindemittel KW - Wasserbeständigkeit KW - Putz KW - Erdbau KW - Kalzinierter Ton PY - 2023 UR - https://www.uni-weimar.de/de/bauingenieurwesen/institute/fib/ibausil/ VL - 2023 SP - 1 EP - 6 PB - Sonderausgabe des Online-Journals ce/papers von Wiley AN - OPUS4-58316 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Becks, H. A1 - Lippold, L. A1 - Winkler, P. A1 - Moeller, M. A1 - Rohrer, M. A1 - Leusmann, T. A1 - Anton, D. A1 - Sprenger, B. A1 - Kähler, P. A1 - Rudenko, I. A1 - Andrés Arcones, Daniel A1 - Koutsourelakis, P. A1 - Unger, Jörg F. A1 - Weiser, M. A1 - Petryna, Y. A1 - Schnellenbach-Held, M. A1 - Lowke, D. A1 - Hessels, H. A1 - Lenzen, A. A1 - Zabel, V. A1 - Könke, C. A1 - Claßen, M. A1 - Hegger, J. T1 - Neuartige Konzepte für die Zustandsüberwachung und -analyse von Brückenbauwerken – Einblicke in das Forschungsvorhaben SPP100+ N2 - Die Brückeninfrastruktur in Deutschland und Europa steht aufgrund steigender Verkehrslasten und alternder Bauwerke vor erheblichen Herausforderungen. Das DFG-Schwerpunktprogramm 2388 „Hundert plus – Verlängerung der Lebensdauer komplexer Baustrukturen durch intelligente Digitalisierung“ (SPP100+) strebt an, durch digitale Innovationen und prädiktive Instandhaltungsstrategien die Nutzungsdauer bestehender Brückenbauwerke zu verlängern. Der vorliegende Beitrag fokussiert sich auf das SPP100+ zugehörige Cluster „Monitoring und Simulation“, das sieben Teilprojekte umfasst. Die Projekte entwickeln fortschrittliche Methoden zur Überwachung und Zustandsbewertung von Brücken mittels Digitaler Zwillinge, hochauflösender Sensortechnik und numerischer Simulationen. Innovative Ansätze wie nichtlineare Modellanpassungen, stochastische Methoden und künstliche Intelligenz ermöglichen eine präzise und frühzeitige Identifizierung potenzieller Schäden. Die Kombination aus kontinuierlichem Bauwerksmonitoring und effizienter Datenauswertung ist entscheidend für die langfristige Sicherheit und Langlebigkeit bestehender Brücken und trägt darüber hinaus zur Ressourcenschonung bei. KW - Bauwerkserhaltung KW - Brückenbau KW - Monitoring KW - Lebensdauer PY - 2024 DO - https://doi.org/10.37544/0005-6650-2024-10-63 SN - 0005-6650 VL - 99 IS - 10 SP - 327 EP - 338 PB - VDI Verlag-eLibrary - technisches Wissen für Ingenieur*innen CY - Düssledorf AN - OPUS4-61563 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - von Werder, Julia T1 - Biorezeptivität und Optimierung von Lehmbaustoffen - Forschung an der BAM N2 - Der Vortrag fasst die Forschungsaktivitäten der BAM in den Themengebieten Biorezeptivität von Beton und Optimierung von Lehmbaustoffen zusammen. Er diente als Kurzpräsentation für eine anschließende Podiumsdiskussion. T2 - Transformationsdialog "Material als Motor" CY - Berlin, Germany DA - 10.10.2024 KW - Biorezeptivität KW - Beton KW - Lehmbaustoffe PY - 2024 AN - OPUS4-62220 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Tyagi, Divyansh T1 - Identification of cracks from experimental modal data using sparsifying priors N2 - Computer models of civil structures like wind turbines, dams, bridges etc., find their use in predicting the structure’s behaviour under different loading conditions. The structure response might change over a period of time for the same loading conditions if some form of damage, e.g., cracks build up in the structure. A previously calibrated model thus won’t produce reliable results in this situation. The model needs to account for the damage to make reliable predictions. The goal here is to predict the location of cracks i.e., damage regions and the corresponding magnitude of damage in these regions. The response e.g., strain, eigenfrequency of a structure that has undergone damage if measured could be used to identify regions of damage in it. In order to perform this identification, the Bayesian inference is deployed. Each crack is modelled as a function that approximates the failure mechanics. A certain number of these cracks are assumed to be distributed in the domain. Their positions and their corresponding damage magnitude are put in as priors. The latter is defined as a sparsifying prior [1] that promotes sparsity in the set of inferred parameters. Therefore, on performing the inference some of the initially assumed cracks are discarded and the remaining cracks are identified and located. The modal data providing the eigenfrequency response of a concrete slab under an increasing load is used for the inference problem. The increasing damage is marked by a decreasing eigenfrequency response of the slab. Horizontal cracks that appear as the slab undergoes damage are identified, located and their contribution to the overall damage magnitude is identified. T2 - ECCOMAS Congress 2024 / The 9th European Congress on Computational Methods in Applied Sciences and Engineering CY - Lisbon, Portugal DA - 03.06.2024 KW - Bayesian Inference KW - Solid Mechanics KW - Damage KW - Sparsifying Priors PY - 2024 AN - OPUS4-61764 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kremberg, Jan T1 - Fire tests of carbon tension members for lightweight constructions N2 - Vorstellung der Brandversuche im Rahmen des Projektes NeZuCa an Carbonzuggliedern für den Brückenbau. T2 - ClimateChange@FireScience CY - Berlin, Germany DA - 10.11.2022 KW - Fire tests KW - Carbon KW - Lightweight constructions KW - Fire Science PY - 2022 AN - OPUS4-56302 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Pirskawetz, Stephan T1 - Spanndrahtbrüche und ihr digitaler akustischer Zwilling N2 - Die Planung eines Monitorings von Spanndrahtbrüchen mit Schallemissionsanalyse erfordert viel Erfahrung und setzt eine akustische Analyse der Spannbetonstruktur voraus. Eine akustische Simulation der Struktur unterstützt die Optimierung der Sensoranordnung und erhöht die Zuverlässigkeit der Drahtbrucherkennung durch die Fusion von Simulations- und Messergebnissen in einer Datenbank. Künftig können Baulastträger und Monitoringanbieter von standardisierten – FAIR-en – akustischen Daten profitieren. T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM Green Intelligent Building CY - Berlin, Germany DA - 16.10.2024 KW - Spanndrahtbrüche KW - Spannbetonbau KW - Spannbetonbrücken KW - Digitaler akustischer Zwilling PY - 2024 AN - OPUS4-61740 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Spilker, A. A1 - Stelzner, Ludwig A1 - Weise, Frank A1 - Wieland, M. T1 - Analyse der thermischen Dehnung von Fahrbahndeckenbetonen aus dem BAB-Netz N2 - Die Kenntnis von Materialeigenschaften spielt bei der Entwicklung oder Optimierung von Betonen und Bauweisen für den Straßenbau sowie der Qualitätssicherung eine bedeutende Rolle. Gleichermaßen bilden physikalische Materialkennwerte die Grundlage für die rechnerische Dimensionierung und die Restsubstanzbewertung von Betonfahrbahndecken. Eine relevante Kenngröße bei der Untersuchung thermisch induzierter Spannungs- und Verformungszustände stellt der thermische Ausdehnungskoeffizient dar. Im Zuge der systematischen Weiterentwicklung der rechnerischen Dimensionierung, aber auch im Zusammenhang mit der gezielten Verbesserung der Gebrauchseigenschaften von Betonfahrbahndecken gilt es zu hinterfragen, ob lastunabhängige Formänderungseigenschaften der verwendeten Betone aktuell ausreichend Beachtung finden, ob allgemeine Literaturwerte für die heutigen Fahrbandeckenbetone stets Gültigkeit besitzen und ob deren Implementierung in numerische Modelle zu realitätsnahen Vorhersagen führt. Für eine empirische Herangehensweise ist die Verfügbarkeit adäquater Prüfverfahren von entscheidender Bedeutung. In Deutschland existiert aktuell jedoch kein standardisiertes oder genormtes Verfahren für die prüftechnische Bestimmung des thermischen Ausdehnungskoeffizienten von Beton. Daher wurden unter Beachtung straßenbauspezifischer Gesichtspunkte zwei Prüfansätze entwickelt, die in diesem Beitrag vorgestellt sowie hinsichtlich möglicher Messunsicherheiten und Messungenauigkeiten diskutiert werden. Außerdem werden ausgewählte Ergebnisse aus Analysen an Bestandsbetonen aus dem BAB-Netz dargestellt. Im Ergebnis sollen die Untersuchungen einen Beitrag zur Schaffung der prüftechnischen Voraussetzungen für eine abgesicherte Quantifzierung der thermischen Dehnung von Fahrbahndeckenbetonen leisten. KW - Betonfahrbahndecken KW - Materialkennwerte KW - Thermischer Ausdehnungkoeffizient KW - Prüfverfahren PY - 2020 DO - https://doi.org/10.1002/best.202000044 VL - 116 IS - 1 SP - 26 EP - 34 PB - John Wiley & Sons AN - OPUS4-54967 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Weise, Frank T1 - Bewertung der Innenhydrophobierung als neuartige AKR-Vermeidungsstrategie bei Betonfahrbahndecken N2 - Zur Vermeidung von AKR-Schäden an Betonfahrbahndecken im deutschen Autobahnnetz wurden mit dem ARS 04/2013 verbindliche Eignungsprüfungen zum Ausschluss alkaliempfindlicher Gesteinskörnungen bei Neubau- und Erhaltungsmaßnahmen eingeführt. Das hatte eine signifikante Reduzierung geeigneter Gesteinskörnungen zur Folge. Deshalb wird geprüft, ob durch die Zugabe eines Hydrophobierungsmittels während der Betonherstellung grenzwertig alkaliempfindliche Gesteinskörnungen nutzbar gemacht werden können. In diesem Beitrag wird der Einfluss der Dosierung eines Compounds mit Hydrophobierungsmittel (HM) auf die Frisch- und Festbetoneigenschaften eines Waschbetons mit einer reaktiven Grauwacke dargestellt. Es zeigt sich, dass aufgrund des Antagonismus die zunehmende Dosierung des HM-Compounds eine signifikante Erhöhung der Zugabe des Luftporenbildners auf Wurzelharzbasis erfordert. Der AKR-Schädigungsprozess wird ab einer Dosierung des HM-Compounds von 0,75 M.-%, bezogen auf den Zementgehalt, hinreichend vermindert. Die mechanischen Eigenschaften des hydrophobierten Waschbetons verschlechtern sich im betrachteten Dosierungsbereich des HM-Compounds nur geringfügig. Auch der Frost-Tausalz-Widerstand vermindert sich, ohne den normativen Grenzwert für die Abwitterung zu überschreiten. T2 - 21. Internationale Baustofftagung ibausil CY - Weimar DA - 13.09.2023 KW - Alkali-Kieselsäure-Reaktion KW - Betonfahrbahndecke KW - Innenhydrophobierung KW - AKR-Vermeidung PY - 2023 AN - OPUS4-58357 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Erning, Johann Wilhelm T1 - "Grabenkorrosion": How scientific debate leads to an solution. And modern failures due to neglection of well described facts N2 - In the late 1980s, a new type of corrosion appeared in drinking water installations where galvanized steel pipes failed forming a deep groove with no corrosion at the other surfaces. The reason was discussed quite fiercely between failure analysts and material suppliers. In the end the discussion lead to the solution: inductive welded pipes of a certain sulphur content were prone to selective corrosion. The history of the arguments is discussed using old communications between Wilhelm Schwenk and Wolfgang Stichel, who later published the results in a paper unfortunately only I german. Thus the knowledge got lost and new cases based on the same material problems are observed in application of so-called C-Steel piping systems. Failure cases are shown. T2 - MTech 2023 CY - Cavtat, Croatia DA - 02.10.2023 KW - Corrosion KW - Grabenkorrosion PY - 2023 AN - OPUS4-58518 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Milks, A. A1 - Lehmann, J. A1 - Leder, D. A1 - Sietz, M. A1 - Koddenberg, T. A1 - Böhner, U. A1 - Wachtendorf, Volker A1 - Terberger, T. T1 - A double-pointed wooden throwing stick from Schöningen, Germany: Results and new insights from a multianalytical study N2 - The site of Schöningen (Germany), dated to ca. 300,000 years ago, yielded the earliest large-scale record of humanly-made wooden tools. These include wooden spears and shorter double-pointed sticks, discovered in association with herbivores that were hunted and butchered along a lakeshore. Wooden tools have not been systematically analysed to the same standard as other Palaeolithic technologies, such as lithic or bone tools. Our multianalytical study includes micro-CT scanning, 3-dimensional microscopy, and Fourier transform infrared spectroscopy, supporting a systematic technological and taphonomic analysis, thus setting a new standard for wooden tool analysis. In illustrating the biography of one of Schöningen’s double-pointed sticks, we demonstrate new human behaviours for this time period, including sophisticated woodworking techniques. The hominins selected a spruce branch which they then debarked and shaped into an aerodynamic and ergonomic tool. They likely seasoned the wood to avoid cracking and warping. After a long period of use, it was probably lost while hunting, and was then rapidly buried in mud. Taphonomic alterations include damage from trampling, fungal attack, root damage and compression. Through our detailed analysis we show that Middle Pleistocene humans had a rich awareness of raw material properties, and possessed sophisticated woodworking skills. Alongside new detailed morphometrics of the object, an ethnographic review supports a primary function as a throwing stick for hunting, indicating potential hunting strategies and social contexts including for communal hunts involving children. The Schöningen throwing sticks may have been used to strategically disadvantage larger ungulates, potentially from distances of up to 30 metres. They also demonstrate that the hominins were technologically capable of capturing smaller fast prey and avian fauna, a behaviour evidenced at contemporaneous Middle Pleistocene archaeological sites. KW - FTIR KW - Stone Age KW - Middle Pleistocene KW - Throwing-stick KW - Wood KW - Micro-CT scanning KW - 3-dimensional microscopy PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-580012 DO - https://doi.org/10.1371/journal.pone.0287719 SN - 1932-6203 VL - 18 IS - 7 SP - 1 EP - 32 PB - PLOS CY - San Francisco, California, US AN - OPUS4-58001 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Burkert, Andreas T1 - Einführung in die Korrosion metallener Werkstoffe N2 - Im Vortrag werden die wesentlichen Grundlagen zum Verständnis der Korrosion metallener Werkstoffe in komprimierter Form vorgestellt. Der Schwerpunkt liegt auf der Betrachtung der atmosphärischen Korrosion und den sich daraus ergebenden Anforderungen an den Korrosionsschutz insbesondere für den Bereich Verpackungen. T2 - CORPAC Seminar: Wie lassen sich VCI-Korrosionsschutz und Nachhaltigkeit vereinbaren? CY - Weidhausen bei Coburg/Germany DA - 29.03.2023 KW - Atmosphärische Korrosion KW - Einflussparameter KW - Befeuchtungsdauer PY - 2023 AN - OPUS4-57250 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hering, Marcus A1 - Sievers, Jürgen A1 - Curbach, Manfred A1 - Beckmann, Birgit T1 - An Approach to Predicting the Ballistic Limit of Thin Textile-Reinforced Concrete Plates Based on Experimental Results N2 - In this article, a partial selection of experiments on enhancing the impact resistance of structural components with non-metallic, textile-reinforced concrete is discussed. The focus is on the experimental investigations in which the impact resistance of thin, textile-reinforced concrete plates is characterized. The article discusses the materials, fabrics and test setup used. For the experimental work, a drop tower from the Otto Mohr Laboratory, which belongs to the Technische Universtät Dresden, was used. Furthermore, the experimental results are presented and evaluated using different methods. Based on the collected data, a suitable approach to determining the perforation velocity of an impactor through the investigated thin, textile-reinforced concrete plates is shown. KW - Building and Construction KW - Civil and Structural Engineering PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-586692 DO - https://doi.org/10.3390/buildings13092234 VL - 13 IS - 9 SP - 1 EP - 14 PB - MDPI AN - OPUS4-58669 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Stelzner, Ludwig A1 - Powierza, Bartosz A1 - Oesch, Tyler A1 - Dlugosch, R. A1 - Weise, Frank T1 - Thermally-induced moisture transport in high-performance concrete studied by X-ray-CT and 1H-NMR N2 - The thermohydraulic damage mechanism is one of the primary causes for explosive spalling of highperformance concrete. This paper presents the spatially- and temporally-resolved analysis of the thermally-induced moisture transport and reconfiguration processes by means of X-ray-CT and 1HNMR. Thermal testing results for a high-performance concrete, which is sensitive to explosive spalling and which was prepared with and without added polypropylene fibres, are presented in this paper. These results indicate that the addition of fibres leads to a faster and deeper migration of the drying front and, thus, to a lower likelihood of vapour-pressure induced explosive spalling. KW - Explosive spalling KW - Thermally-induced moisture transport KW - X-ray-CT KW - 1H-NMR KW - High-performance concrete PY - 2019 DO - https://doi.org/10.1016/j.conbuildmat.2019.07.065 SN - 0950-0618 VL - 224 SP - 600 EP - 609 PB - Elsevier Ltd. AN - OPUS4-48727 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ratkovac, Mirjana A1 - Gerards-Wünsche, Paul A1 - Thiele, Marc A1 - Brackrock, Daniel A1 - Stamm, Michael T1 - Detection and monitoring of the fatigue crack growth on welds – Application-oriented use of NDT methods N2 - Early detection of fatigue cracks and accurate measurements of the crack growth play an important role in the maintenance and repair strategies of steel structures exposed to cyclic loads during their service life. Observation of welded connections is especially of high relevance due to their higher susceptibility to fatigue damage. The aim of this contribution was to monitor fatigue crack growth in thick welded specimens during fatigue tests as holistically as possible, by implementing multiple NDT methods simultaneously in order to record the crack initiation and propagation until the final fracture. In addition to well-known methods such as strain gauges, thermography, and ultrasound, the crack luminescence method developed at the Bundesanstalt für Materialforschung und -prüfung (BAM), which makes cracks on the surface particularly visible, was also used. For data acquisition, a first data fusion concept was developed and applied in order to synchronize the data of the different methods and to evaluate them to a large extent automatically. The resulting database can ultimately also be used to access, view, and analyze the experimental data for various NDT methods. During the conducted fatigue tests, the simultaneous measurements of the same cracking process enabled a comprehensive comparison of the methods, highlighting their individual strengths and limitations. More importantly, they showed how a synergetic combination of different NDT methods can be beneficial for implementation in large-scale fatigue testing but also in monitoring and inspection programs of in-service structures - such as the support structures of offshore wind turbines. T2 - Fatigue Design 2023 (FatDes 2023) CY - Senlis, France DA - 29.11.2023 KW - Fatigue KW - Welded KW - NDT KW - Crack growth PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-600238 DO - https://doi.org/10.1016/j.prostr.2024.03.062 VL - 57 SP - 560 EP - 568 PB - Elsevier B.V. AN - OPUS4-60023 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bäßler, Ralph A1 - Amela Keserović, Amela A1 - Sobetzki, Joana A1 - Sarmiento Klapper, Helmuth A1 - Dimper, Matthias T1 - Geeignete Werkstoffe für Geothermieanwendungen (1) N2 - Durch Auslagerungs- und elektrochemische Tests im Labor kann das Korrosionsverhalten verschiedener metallener Werkstoffe beurteilt werden. Aus den Versuchsergebnissen, die in verschiedenen synthetischen Geothermalwässern im Labor erzielt wurden, lassen sich die folgenden Schlussfolgerungen ziehen: • Die Anfälligkeit für Spaltkorrosion wurde als wichtigster Aspekt für die Werkstoffqualifizierung ermittelt. • Der niedriglegierte Stahl 25CrMo4 zeigte bei niedrigem Salzgehalt in MB-Geothermalwasser eine gleichmäßige Korrosion unterhalb der akzeptierten Schwelle von 0,3 mm/Jahr. Daher kann er als geeignet für geothermische Bedingungen mit niedrigem Salzgehalt angesehen werden, wie sie für MB getestet wurden. Es besteht keine Notwendigkeit, auf höherlegierte (teurere) Werkstoffe auszuweichen. Ein niedrigerer pH-Wert (wie bei LHD) führt zu Korrosionsraten oberhalb der akzeptablen Grenzwerte, so dass die niedriglegierten Werkstoffe nicht für Flüssigkeiten mit niedrigem pH-Wert geeignet sind. • Stark salzhaltige Geothermalwässer erfordern höherlegierte Werkstoffe, da die Korrosionsrate von niedriglegiertem Stahl zu hoch ist. • Der Duplexstahl X2CrNiMo22-5-3 und der Superduplexstahl X2CrNiMoCuWN25-7-4 wurden aufgrund ihrer kritischen Anfälligkeit für örtliche Korrosion in Form von Loch- und Spaltkorrosion unter Betriebsbedingungen nicht als geeignet für geothermische Anwendungen in Geothermalwässern mit einer mit NDB und ORG vergleichbaren Zusammensetzung angesehen. • Der superaustenitische Stahl X1CrNiMoCu32-28-7 eignet sich für ORG und salzarme Wässer. In NDB-Geothermalwasser wurde er bei 100 °C als geeignet angesehen. Jedoch schränkt seine Anfälligkeit für Spaltkorrosion seine Anwendbarkeit ein. Neben seiner guten Korrosionsbeständigkeit ist sein Repassivierungsverhalten für seine begrenzte Anwendbarkeit in Geothermalwässern mit niedrigem pH-Wert verantwortlich. • Die Nickelbasislegierung NiCr23Mo16Al wurde als geeignet erachtet und stellt eine sichere Option für den Einsatz in geothermischen Anlagen dar, selbst wenn mit stark salzhaltigem Geothermalwasser gearbeitet wird. KW - Geothermie KW - Korrosion KW - Legierungen KW - Anlagensicherheit PY - 2024 SN - 0016-4232 VL - 2024 IS - 2 SP - 240 EP - 243 PB - Eugen G. Leuze Verlag CY - Bad Saulgau AN - OPUS4-59996 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Scholz, Philipp A1 - Wachtendorf, Volker A1 - Elert, Anna Maria A1 - Falkenhagen, Jana A1 - Becker, Roland A1 - Hoffmann, Katrin A1 - Resch-Genger, Ute A1 - Tschiche, Harald A1 - Reinsch, Stefan A1 - Weidner, Steffen ED - Scholz, Philipp T1 - Analytical toolset to characterize polyurethanes after exposure to artificial weathering under systematically varied moisture conditions N2 - Polyether and -ester urethanes (PU) were exposed to artificial weathering at 40 °C and artificial UV radiation in a weathering chamber. In 3 parallel exposures, humidity was varied between dry, humid, and wet conditions. Material alteration was investigated by various analytical techniques like size exclusion chromatography (SEC), liquid chromatography-infrared spectroscopy (LC-FTIR), thermal-desorption gas chromatography-mass spectrometry (TD-GC-MS), fluorescence mapping and dynamic mechanical analysis (DMA). Our results show that depending on the weathering conditions, different degradation effects can be observed. By means of SEC an initial strong decrease of the molar masses and a broadening of the mass distributions was found. After a material dependent time span this was followed by a plateau where molar mass changes were less significant. A minor moisture-dependent degradation effect was only found for polyester PU. Fluorescence measurements on two materials revealed an increase in the luminescence intensity upon weathering process reaching a saturation level after about 500 h. The changes in the optical properties observed after different exposure conditions and times were very similar. The TD-GC-MS data showed the fate of the stabilizers and antioxidant in the course of weathering. LC-FTIR measurements revealed a change in peak intensities and the ratio of urethane and carbonyl bands. KW - Polyurethane KW - Artificial weathering KW - Moisture KW - Crosslinking KW - Degradation PY - 2019 UR - https://www.sciencedirect.com/science/article/pii/S0142941819303708 DO - https://doi.org/10.1016/j.polymertesting.2019.105996 SN - 0142-9418 VL - 78 SP - 105996, 1 EP - 9 PB - Elsevier CY - Amsterdam AN - OPUS4-48625 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Beck, Joana T1 - Rezension: Prozessmanagement - Kundennutzen, Produktivität, Agilität N2 - Effizienz und Qualität sind schon immer Antriebsmotoren für die Wirtschaft. Um das heutzutage in einer stetig schneller agierenden Welt zu erreichen, wird konsequentes Prozessmanagement immer wichtiger. Dabei werden Prozesse nicht nur klar und eindeutig beschrieben, sondern auch Kompetenzen, Aufgaben und Verantwortlichkeiten festgelegt, um das Resultat für den Kunden in den Fokus zu rücken und zeitraubende Hierarchiekämpfe zu vermeiden. Der Autor untermalt die gut strukturierten Textpassagen, in denen wichtige Schlagworte fett abgedruckt sind, mit vielen Schaubildern zu Prozessen und übersichtlichen Tabellen. Er gibt dem Leser Werkzeuge in Form von Checklisten sowie Diagnoseplänen und Analyseformularen. Gleichzeitig wird durch beispielhaft ausgefüllte Formulare (Checklisten) der Praxisbezug anhand unterschiedlicher Branchenbereiche wie z.B. Controlling, Produktion, Medizin, etc. hergestellt. Somit liegt hier ein Arbeitsbuch vor für jeden, der gleich losstarten möchte. KW - Prozessmanagement KW - Qualitätsmanagement PY - 2019 DO - https://doi.org/10.1002/maco.201970106 SN - 1521-4176 SN - 0947-5117 VL - 70 IS - 10 SP - 3 EP - 4 PB - Wiley‐VCH CY - Weinheim AN - OPUS4-49303 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Persson, K. T1 - The EC4SafeNano Project - and the case study of Surface Chemical Transformations of Nano-TiO2 Samples upon Weathering N2 - A central challenge to ensure the sustainable production and use of nanotechnologies is to understand and effectively control the risks along the industrial innovation value chain. Knowledge about nanotechnology processes and nanosafety issues (hazards, fate, risk...) is growing rapidly but the effective use of this knowledge for risk management by market actors is lagging behind. EC4SafeNano (European Centre for Risk Management and Safe Innovation in Nanomaterials and Nanotechnologies) promotes a harmonized vision of expertise in risk assessment and management for the public and private sectors to enable the safe development and commercialization of nanotechnology. EC4SafeNano is operated together by major European risk institutes with the support of numerous associated partners, gathering all stakeholders involved in Nanomaterials and Nanotechnologies (regulators, industry, society, research, service providers...). In a case study the surface chemical transformations upon 2 different ageing procedures (long-term UV irradiation or swimming pool water) of a representative set of titanium dioxide nanoparticles has been investigated. The materials have been analyzed by various analytical techniques. Each method addresses different aspects of the complex endpoint surface chemistry. The multi technique approach allows evaluation of the capabilities and limitations of the applied methods regarding their suitability to address the endpoint surface chemistry and their sensitivity to identify even small surface chemical transformations. Results: - To obtain a comprehensive picture, it is insufficient to concentrate on a single analysis technique. - By using time-of-flight secondary ion mass spectrometry (ToF-SIMS) in combination with principal component analysis (PCA) it was possible to identify even subtle changes in the surface chemistry of the investigated materials. - A general trend that was observed for the UV-aged samples is the decrease of organic material on the nanomaterial surface. This project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 723623. T2 - FormulaX/NanoFormulation 2019 CY - Manchester, England, United Kingdom DA - 24.06.2019 KW - TiO2 nanoparticle KW - Surface Chemical Transformation KW - UV Weathering KW - SIMS KW - XPS KW - IR spectroscopy KW - EC4SafeNano PY - 2019 UR - https://www.formulation.org.uk/images/stories/FormulaX/Posters/P-14.pdf AN - OPUS4-48912 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Bäßler, Ralph T1 - Rezension: Verschleiß metallischer Werkstoffe ‐ Erscheinungsformen sicher beurteilen N2 - Das in der 3. Auflage vorliegende Fachbuch wird die praktische Arbeit des Ingenieurs bei der Beurteilung von Verschleißerscheinungen unterstützen. In acht Kapiteln behandeln die Autoren alle interessanten Aspekte zu diesem Thema. Zielgruppen sind Maschinen-bauingenieure, Techniker und Werkstofftechniker in der Entwicklung, Konstruktion und Instandhaltung. Sie werden für ihre Arbeit im Buch gute Unterstützung und Anregungen für ihre praktische Arbeitfinden. KW - Verschleiß PY - 2019 DO - https://doi.org/10.1002/maco.201970096 SN - 1521-4176 SN - 0947-5117 VL - 70 IS - 9 SP - 4 EP - 4 PB - WILEY‐VCH Verlag GmbH & Co. KGaA CY - Weinheim AN - OPUS4-48887 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Geburtig, Anja A1 - Wachtendorf, Volker A1 - Trubiroha, P. T1 - Exposure response function for a quantitative prediction of weathering caused aging of polyethylene N2 - The exposure response function of the carbonyl formation over the bulk has been determined for a high-density polyethylene of a thickness of 200 μm, which was used as a weathering reference material according to ISO TR 19032. To this end, spectral sensitivity was studied by local measurement of the effect of spectrally dispersed irradiation. Both the exposure device and the methodology of determination are described. The temperature dependency of photooxidation was determined by UV exposure at various temperatures between 23 and 80 °C. Deviations from linearity and thus reciprocity below 40 °C are discussed and assumed to be related to diffusion limitations. An Arrhenius approach –based on data of linear carbonyl formation – has been incorporated into the exposure response function. Using this exposure response function, aging in terms of the distribution of a quantitative property change over a plastic component can be predicted for a specific outdoor location with real chronologic weather data as input for the exposure. Thus, artificial and natural weathering can be linked and compared. The established exposure response function has been validated by outdoor exposure results from the literature. If an estimated diffusion limitation is taken into consideration, calculations and published data are in good agreement. KW - Irradiation KW - Weathering KW - Spectral sensitivity KW - Temperature dependency KW - Spectral irradiation PY - 2019 DO - https://doi.org/10.3139/120.111348 SN - 0025-5300 VL - 61 IS - 6 SP - 517 EP - 526 PB - Carl Hanser Verlag GmbH & Co. KG AN - OPUS4-48295 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Thuy, Maximilian T1 - Influence of molecular orientation on the environmental stress cracking resistance N2 - Molecular orientation has a significant effect on the material properties of polymers. Preferential orientation of the microstructure (polymer chains or crystallites) in a specific direction or plane often enhances the material properties, especially if the high-strength covalent bonds are primarily exposed to loads instead of the weaker van der Waals bonds. However, the orientation-dependent microstructure and its mechanical behavior is in general already well understood by many scientific studies [1-3]. Isotropic materials are frequently required for an intrinsic material characterization without prevailing processing-induced properties, as is the case for Full Notch Creep Test (FNCT) [4] addressing environmental stress cracking (ESC) in high-density polyethylene (PE-HD) [5, 6]. Since ESC is one of the major limiting issues for long-term performance of PE-HD pipes and containers [7], which in contrast have a production-related preferential orientated microstructure due to extrusion or extrusion blow molding, it is important to additionally investigate the ESC resistance of such anisotropic microstructure. Investigations of the slow crack growth (SCG) with respect to the molecular orientation generally obtain a factor of 1.2 up to 4.7 between crack growth perpendicular to the extrusion direction and crack growth parallel to the extrusion direction 8. Based on FNCT investigations with an aqueous detergent solution as environmental medium, hot pressed sheets with isotropic morphology are compared with extruded sheets from which specimens with different orientation angles are taken. However, the time to failure obtained by FNCT is also significantly influenced by the different cooling conditions under which the final morphology is formed. The tendency of the specimen to fail due to ESC is investigated as a function of environmental medium temperature. For a more detailed analysis of the affecting parameters in the manufacturing process, the ESC resistance is discussed considering the differences in crystallinity as revealed by thermal analysis. T2 - 36th International Conference of the Polymer Processing Society CY - Montreal, Canada DA - 26.09.2021 KW - Environmental stress cracking KW - Orientation-dependent microstructure KW - High-density polyethylene KW - Full Notch Creep Test PY - 2021 AN - OPUS4-53399 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Miccoli, Lorenzo A1 - Silva, R. A. A1 - Oliveira, D. V. A1 - Müller, U. T1 - Static behavior of cob: Experimental testing and finite-element modeling N2 - The aim of this paper is to implement a numerical model to reproduce the nonlinear behavior of cob walls under shear loading. Axial compression, pull-off, and diagonal compression tests were carried out to derive the mechanical parameters. In addition, the stressstrain relationships, the nonlinear behavior, and the failure modes were defined. The experimental results were then used to calibrate a finiteelement model. The material behavior was simulated through a macromodeling approach adopting the total strain rotating crack model. A sensitivity analysis was conducted to assess the effects of varying the parameters with higher uncertainty on the structural behavior. The numerical model achieved good correspondence with the experimental results in terms of simulation of the shear stress–shear strain relationship and of damage pattern. KW - Cob KW - Compression behavior KW - Shear behavior KW - Digital image correlation KW - Finite-element method PY - 2019 DO - https://doi.org/10.1061/(ASCE)MT.1943-5533.0002638 SN - 0899-1561 SN - 1943-5533 VL - 31 IS - 4 SP - 04019021-1 EP - 04019021-13 PB - ASCE American Society of Civil Engineers AN - OPUS4-47316 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Bäßler, Ralph T1 - Rezension: Projektarbeit bei kleinen und mittleren Vorhaben − Strukturiertes Vorgehen und überlegtes Handeln als Schlüssel zum Erfolg N2 - Der 2005 erstmalig erschienene und bewährte "Projektmanagement‐Kompass" wurde durch den auf diesem Gebiet erfahrenen Autor auf den neuesten Stand gebracht und zum 4. Mal neu aufgelegt. Den Lesern soll hiermit geholfen werden,"ihre Projekte strukturiert zu bearbeiten, überlegt zu handeln und ihr Vorhaben zielorientiert durch den Parcours der Überraschungen zu bewegen". In 5 Hauptkapiteln führt das Buch nach einer Übersicht einem Kompass gleich vom Start über die Planung und Umsetzung zum Ende von Projekten. Durch seine klare Struktur, die sich im vorgestellten PM‐Kompass wiederfinden lässt, wird dieses Buch seinem Anspruch, beim Projektmanagement den richtigen Weg zu weisen, gerecht. KW - Projektmanagement KW - Vorhaben PY - 2019 DO - https://doi.org/10.1002/maco.201970025 SN - 0947-5117 SN - 1521-4176 VL - 70 IS - 2 SP - 3 EP - 4 PB - WILEY-VCH Verlag GmbH & Co. KGaA CY - Weinheim AN - OPUS4-47367 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Musil, B. A1 - Böhning, Martin A1 - Johlitz, M. A1 - Lion, A. T1 - On the inhomogenous chemo-mechanical ageing behaviour of nitrile rubber: experimental investigations, modelling and parameter identification N2 - Elastomers are used in almost all areas of industrial applications, such as tires, engine mounts, bridge bearings, seals or coatings. During their use in operation, they are exposed to different environmental influences. These include, in particular, climatic factors such as air oxygen, high temperatures, light (UV radiation) and the influence of media (e.g. oils, fuels). A very important result of these factors is the chemical ageing of elastomers. In this case, the elastomer degenerates and changes its chemical structure in the aged regions, which leads to an irreversible change in the material properties in connection with the reduction in its usability. In this paper, chemical ageing of nitrile butadiene rubber (NBR) is investigated. Especially in case of thermo-oxidative ageing at elevated operating temperatures, the ageing processes run inhomogeneously. These effects are known as diffusion-limited oxidation (DLO) and are associated with the diffusion–reaction behaviour of atmospheric oxygen with the elastomer network. For these reasons, NBR samples are artificially aged in air and subjected to different experimental methods, which are presented and discussed. Additional results from inhomogeneous mechanical tests and permeation tests indicate the causes of the DLO-effect, show the influence of chemical ageing and are subsequently used for parameter identification in relation to the diffusion–reaction equation. A continuum-mechanical modelling approach is also presented here, which describes the finite hyperelasticity, diffusion–reaction processes as well as chemical degradation and reformation of the elastomer network. This multifield problem leads to a system of partial and ordinary differential equations and constitutive equations and is solved within the finite element method. KW - Rubber KW - Ageing KW - Gas permeability KW - DLO KW - NBR PY - 2019 DO - https://doi.org/10.1007/s00161-019-00791-1 SN - 0935-1175 SN - 1432-0959 VL - 32 IS - 1 SP - 127 EP - 146 PB - Springer CY - Heidelberg AN - OPUS4-48560 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Knauer, S A1 - Le, Quynh Hoa A1 - Bäßler, Ralph A1 - Jaeger, P T1 - Contact angle and corrosion of a Water – CO2 system on X70 and S41500 at 278 K and pressures up to 20 MPa N2 - Interfacial properties related to wettability and corrosion in CO2 transport pipelines are experimentally determined by the sessile and the pendant drop methods. The contact angle of a water drop in a compressed CO2 atmosphere is analyzed on an X70 pipeline carbon steel and compared to that on a martensitic steel S41500 to elucidate the effect of corrosion process on active wetting behaviour. The measurements are performed with liquid CO2 at 278 K and pressures ranging from 5 to 20 MPa. The results show that the contact angle (CA) increases with pressure from 132 ° to 143 ° for S41500 and from 117 ° to 137 ° for X70 and decreases with drop age by 20 ° to 24 ° regardless of the pressure and of the fact that corrosion only occurs on X70, which is confirmed by scanning electron microscopy, element mapping and energy dispersive x-ray spectrometry (EDS) analysis. At higher pressure, the contact angles on both materials converge. Further, related properties like density and interfacial tension were determined. CO2 - saturated water has a higher density than pure water: At 5 MPa saturated water reaches a density of 1017 kg⋅m^(-3) and at 20 MPa 1026 kg⋅m^(-3) compared to pure water with a density of 1002 kg⋅m^(-3) and 1009 kg⋅m^(-3), respectively. In this pressure range the IFT drops from 33 mN⋅m^(-1)at 5 MPa to 23 mN⋅m^(-1) at 20 MPa. KW - Carbon capture KW - Utilization, and storage (CCUS) technology KW - Contact angle KW - Wetting KW - Corrosion KW - Condensate KW - Impurities KW - Carbon steel PY - 2019 UR - https://www.sciencedirect.com/science/article/pii/S1750583618309472?dgcid=author DO - https://doi.org/10.1016/j.ijggc.2019.06.021 SN - 1750-5836 SN - 1878-0148 VL - 89 SP - 33 EP - 39 PB - Elsevier, ScienceDirect AN - OPUS4-48601 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Reinemann, Steffi A1 - Rosemann, P. A1 - Babutzka, Martin A1 - Lehmann, Jens A1 - Burkert, Andreas T1 - Influence of grinding parameters on the corrosion behavior of austenitic stainless steel N2 - Samples of the austenitic stainless steel grade X5CrNi18‐10 (1.4301, AISI 304) were ground industrially with various grinding parameters to study their influence on corrosion resistance. The ability of the mechanically ground surfaces to form a stable passive layer was evaluated by KorroPad test and a modified electrochemical potentiodynamic reactivation test based on a single loop (EPR‐SL). Furthermore, the surfaces were characterized by surface analytical methods. The main influence was determined regarding abrasive belt type. Surfaces mechanically ground with granulate abrasive belts constantly had a lower corrosion resistance than surfaces ground with single‐coated grain. The granulate abrasive belts generated more sensitized surface areas and left formations of welded sample material on the mechanically ground surfaces. A post‐treatment with a nonwoven abrasive proved to be an effective finishing process by which the surface defects and sensitized material got removed and the surfaces regained the expected corrosion resistance. KW - Abrasive belt KW - Austenitic stainless steel KW - Electrochemical potentiodynamic reactivation KW - Grinding KW - KorroPad KW - Surface KW - Corrosion PY - 2019 DO - https://doi.org/10.1002/maco.201910874 SN - 0947-5117 SN - 1521-4176 VL - 70 IS - 10 SP - 1776 EP - 1787 PB - Wiley-VCH Verlag CY - Weinheim AN - OPUS4-47871 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Bäßler, Ralph T1 - Rezension: Wärmebehandlung von Eisenwerkstoffen II − Nitrieren und Nitrocarburieren N2 - Das 1986 erstmalig erschienene und bewährte Fachbuch wurde, nachdem die 2014 herausgegebene 6. Auflage vergriffen war, auf den neuesten Stand gebracht und im Rahmen der,,Kontakt & Studium“‐Serie der Technischen Akademie Esslingen als Band 686 neu aufgelegt, um die ungebrochene Nachfrage zu befriedigen. Dabei wurden die nach der vorherigen Ausgabe geänderten Normen sowie einige Abbildungen und die Liste der Dissertationen aktualisiert. Wie schon in den vorherigen Ausgaben bietet dieses Buch Studierenden der technischen Fach‐ und Hochschulen eine gute Unterstützung und ist insbesondere für die in der Industrie tätigen Techniker, Konstrukteure und Ingenieure zu empfehlen. Die aktualisierte Bibliographie der zum Thema einschlägigen Dissertationsschriften am Ende des Werkes bietet auch einen hohen Nutzen für den wissenschaftlichen Gebrauch. KW - Korrosion KW - Legierung KW - Nitrieren PY - 2019 DO - https://doi.org/10.1002 maco.201970015 SN - 0947-5117 VL - 70 IS - 01 SP - 3 EP - 4 PB - WILEY-VCH Verlag GmbH & Co. KGaA CY - Weinheim AN - OPUS4-47150 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Beck, Joana T1 - Book review: Handbook of material weathering (6th edition) N2 - With its almost 1000 pages and 1.7 kg this handbook feels like holding the holy bible for users of weathering techniques as well as for technicians, engineers and scientist planning to test polymeric products behavior in natural or artificial environments. KW - Corrosion KW - Testing PY - 2019 DO - https://doi.org/10.1002/maco.201970014 SN - 0947-5117 VL - 70 IS - 1 SP - 170 EP - 171 PB - Wiley-VCH CY - Weinheim AN - OPUS4-47149 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Xu, C. A1 - Battig, Alexander A1 - Schartel, Bernhard A1 - Siegel, R. A1 - Senker, J. A1 - von der Forst, I. A1 - Unverzagt, C. A1 - Agarwal, S. A1 - Möglich, A. A1 - Greiner, A. T1 - Investigation of the Thermal Stability of Proteinase K for the Melt Processing of Poly(L‑lactide) N2 - The enzymatic degradation of aliphatic polyesters offers unique opportunities for various use cases in materials science. Although evidently desirable, the implementation of enzymes in technical applications of polyesters is generally challenging due to the thermal lability of enzymes. To prospectively overcome this intrinsic limitation, we here explored the thermal stability of proteinase K at conditions applicable for polymer melt processing, given that this hydrolytic enzyme is well established for its ability to degrade poly(L-lactide) (PLLA). Using assorted spectroscopic methods and enzymatic assays, we investigated the effects of high temperatures on the structure and specific activity of proteinase K. Whereas in solution, irreversible unfolding occurred at temperatures above 75−80 °C, in the dry, bulk state, proteinase K withstood prolonged incubation at elevated temperatures. Unexpectedly little activity loss occurred during incubation at up to 130 °C, and intermediate levels of catalytic activity were preserved at up to 150 °C. The resistance of bulk proteinase K to thermal treatment was slightly enhanced by absorption into polyacrylamide (PAM) particles. Under these conditions, after 5 min at a temperature of 200 °C, which is required for the melt processing of PLLA, proteinase K was not completely denatured but retained around 2% enzymatic activity. Our findings reveal that the thermal processing of proteinase K in the dry state is principally feasible, but equally, they also identify needs and prospects for improvement. The experimental pipeline we establish for proteinase K analysis stands to benefit efforts directed to this end. More broadly, our work sheds light on enzymatically degradable polymers and the thermal processing of enzymes, which are of increasing economical and societal relevance. KW - Enzymatic degradation KW - Poly(L‑lactide) KW - Polyesters KW - biodegradation PY - 2022 DO - https://doi.org/10.1021/acs.biomac.2c01008 SN - 1525-7797 SN - 1526-4602 VL - 23 IS - 11 SP - 4841 EP - 4850 PB - ACS Publications AN - OPUS4-56292 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bäßler, Ralph A1 - Amela Keserović, Amela A1 - Sobetzki, Joana A1 - Sarmiento Klapper, Helmuth A1 - Dimper, Matthias T1 - Geeignete Werkstoffe für Geothermieanwendungen (2) N2 - Durch Auslagerungs- und elektrochemische Tests im Labor kann das Korrosionsverhalten verschiedener metallener Werkstoffe beurteilt werden. Aus den Versuchsergebnissen, die in verschiedenen synthetischen Geothermalwässern im Labor erzielt wurden, lassen sich die folgenden Schlussfolgerungen ziehen: • Die Anfälligkeit für Spaltkorrosion wurde als wichtigster Aspekt für die Werkstoffqualifizierung ermittelt. • Der niedriglegierte Stahl 25CrMo4 zeigte bei niedrigem Salzgehalt in MB-Geothermalwasser eine gleichmäßige Korrosion unterhalb der akzeptierten Schwelle von 0,3 mm/Jahr. Daher kann er als geeignet für geothermische Bedingungen mit niedrigem Salzgehalt angesehen werden, wie sie für MB getestet wurden. Es besteht keine Notwendigkeit, auf höherlegierte (teurere) Werkstoffe auszuweichen. Ein niedrigerer pH-Wert (wie bei LHD) führt zu Korrosionsraten oberhalb der akzeptablen Grenzwerte, so dass die niedriglegierten Werkstoffe nicht für Flüssigkeiten mit niedrigem pH-Wert geeignet sind. • Stark salzhaltige Geothermalwässer erfordern höherlegierte Werkstoffe, da die Korrosionsrate von niedriglegiertem Stahl zu hoch ist. • Der Duplexstahl X2CrNiMo22-5-3 und der Superduplexstahl X2CrNiMoCuWN25-7-4 wurden aufgrund ihrer kritischen Anfälligkeit für örtliche Korrosion in Form von Loch- und Spaltkorrosion unter Betriebsbedingungen nicht als geeignet für geothermische Anwendungen in Geothermalwässern mit einer mit NDB und ORG vergleichbaren Zusammensetzung angesehen. • Der superaustenitische Stahl X1CrNiMoCu32-28-7 eignet sich für ORG und salzarme Wässer. In NDB-Geothermalwasser wurde er bei 100 °C als geeignet angesehen. Jedoch schränkt seine Anfälligkeit für Spaltkorrosion seine Anwendbarkeit ein. Neben seiner guten Korrosionsbeständigkeit ist sein Repassivierungsverhalten für seine begrenzte Anwendbarkeit in Geothermalwässern mit niedrigem pH-Wert verantwortlich. • Die Nickelbasislegierung NiCr23Mo16Al wurde als geeignet erachtet und stellt eine sichere Option für den Einsatz in geothermischen Anlagen dar, selbst wenn mit stark salzhaltigem Geothermalwasser gearbeitet wird. KW - Geothermie KW - Korrosion KW - Legierungen KW - Anlagensicherheit PY - 2024 SN - 0016-4232 VL - 2024 IS - 3 SP - 370 EP - 374 PB - Eugen G. Leuze Verlag CY - Bad Saulgau AN - OPUS4-59997 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Lehmann, Jens T1 - KorroPad - Vom Schadensphänomen zur Prüfmethode für Forschung und betriebliche Anwendung N2 - Eine Erfolgsgeschichte von der praktischen Umsetzung von Forschungsergebnissen für Entwicklung einer Prüfmethode. T2 - GfKORR Jahrestagung - Aktuelles aus der Korrosionsforschung - Nutzen und praktische Anwendungen CY - Frankfurt a. M., Germany DA - 08.11.2022 KW - Korrosion KW - Nichtrostender Stahl KW - KorroPad KW - Korrosionsprüfung PY - 2022 AN - OPUS4-56204 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Geburtig, Anja A1 - Wachtendorf, Volker A1 - Trubiroha, P. A1 - Giehl, A. A1 - Schönlein, A. A1 - Feil, F. T1 - Normenvorschlag zur Bewitterung transparenter oder transluzenter Kunststoffe N2 - Aufgrund des tieferen Eindringens der solaren Strahlung treten bei transparenten und bei transluzenten (durchscheinenden) Kunststoffen veränderte Bedingungen gegenüber opaken Proben auf. Dies kann zu speziellen Effekten und damit zu einem abweichenden Bewitterungsverhalten führen. Auch aus Mangel an geeigneten Normen werden diese Effekte häufig vernachlässigt. Deshalb initiiert der DIN-FNK auf ISO-Ebene ein entsprechendes Dokument. Die Norm ist in der Form eines Technical Reports geplant. In einem ersten Teil sollen die Besonderheiten transparenter oder transluzenter Kunststoffe erläutert werden, um den Nutzer für mögliche Probleme zu sensibilisieren. Im zweiten Teil werden Empfehlungen für Bestrahlung oder Bewitterung herausgearbeitet. In einem dritten Teil geht es dann um Besonderheiten bei der Messung von Eigenschaftsänderungen transparenter bzw. transluzenter Kunststoffe. In informativen Anhängen sollen verschiedene Beispiele die Thematik illustrieren. T2 - 51. Jahrestagung der GUS CY - Stutensee-Blankenloch, Germany DA - 29.03.2023 KW - Bewitterung KW - Polymer 3R KW - Bestrahlung KW - UV PY - 2023 SN - 978-3-9818507-8-9 SP - 39 EP - 46 PB - Gesellschaft für Umweltsimulation e.V. CY - Pfinztal (Berghausen) AN - OPUS4-57271 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Geburtig, Anja A1 - Wachtendorf, Volker A1 - Falkenhagen, Jana T1 - Combined impact of UV radiation and nitric acid (HNO3) on HDPE jerrycans – comparison of outdoor and lab test N2 - A damaging action of HNO3-55% only occurs in combination with its decomposition into nitrous gases, which can be caused by UV radiation. In a laboratory test, transparent HDPE jerrycans have been exposed to both UV radiation and 55 wt-% nitric acid solution at (41 ± 2)°C, for up to 20 days. For comparison, UV radiant exposure (21 days) and nitric acid exposure (up to 6 weeks) were performed separately, at nearly equal temperatures. The respective damages are compared with FTIR spectroscopy in ATR and HT-gel permeation chromatography (GPC) on a molecular level and with hydraulic internal pressure testing as a component test. For the used jerrycans, relevant oxidation can only be found after the combined exposure. The gradual increase in oxidative damage shows the good reproducibility of the lab exposure. The decomposition of nitric acid into nitrous gases by UV radiation – as well as the jerrycan oxidation – is also observed at lower HNO3 concentration (28 wt- %). Similar results are obtained after outdoor tests. Again, the damage occurs only after combined exposure, in contrast to the exposures to UV only and to HNO3 only, which were conducted in parallel. Outdoor exposures are most readily accepted as they represent possible end-use conditions. However, the reproducibility of these exposures is poor due to the large temporal variations in weather. There are also several safety risks, which is why the number of replicates remains limited. Since the outdoor and lab exposure tests show the same qualitative results, it is appropriate to conduct systematic studies in the laboratory. After 6 days of lab exposure, the oxidation damage is rated as critical, which corresponds to about 1/10 year in Central Europe, according to the UV radiant exposure. It should be noted that this amount can also occur in two sunny weeks. T2 - 24th iapri World Packaging Conference CY - Valencia, Spain DA - 17.06.2024 KW - Ppolyethylene KW - UV exposure KW - Nitric acid KW - Oxidation PY - 2024 VL - 2 SP - 30 EP - 37 PB - ITENE AN - OPUS4-60414 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bäßler, Ralph T1 - Wechselwirkungen in Geothermieanlagen - nicht nur ein Beständigkeitsaspekt N2 - Um Konstrukteuren und Nutzern geothermischer Anlagen grundlegende Informationen über die Korrosionsbeständigkeit zur Verfügung zu stellen, wurden verschiedene metallische Werkstoffe, darunter nichtrostende Duplex- und austenitische Stähle sowie eine Nickellegierung, in künstlichen Geothermalwässern bewertet, die die Bedingungen an verschiedenen Standorten mit geothermischem Potenzial simulieren. Mit Hilfe von elektrochemischen und Langzeittests wurde die Eignung verschiedener metallener Werkstoffe mittels kritischer Potentiale und Korrosionsraten untersucht. In hochsalinaren Umgebungen erwies sich Spaltkorrosion als der entscheidende Mechanismus. Die Nickelbasislegierung zeigt eine ausgezeichnete Beständigkeit gegenüber Lochkorrosion. Abgesehen von ihren hohen Kosten eignet sie sich sehr gut für den Bau von Geothermieanlagen mit stark salzhaltigen Fluiden. Rostfreie Stähle und Duplexstähle weisen eine begrenzte Korrosionsbeständigkeit gegen Loch- und Spaltkorrosion auf. Daher sind sie für stark salzhaltige Fluide nicht geeignet. Der Superaustenit zeigt ein temperaturabhängiges Verhalten. In nichtsalinaren Umgebungen könnten niedrig legierte Stähle (neben den höher legierten Werkstoffen) als Konstruktionsmaterial für Geothermieanlagen eingesetzt werden, sofern eine ausreichende Wandstärke des Materials berücksichtigt wird. Neben Korrosionsaspekten erwies sich auch die Ausfällung von Fluidbestandteilen als interessantes Thema. Beim Betrieb der Forschungsanlage in Groß Schönebeck wurden Kupfer- und Bleieffekte im Bohrloch festgestellt. Die auftretenden Mechanismen und Maßnahmen zur Verhinderung von Ausfällungen und Abscheidungen wurden ebenso untersucht, wie deren mögliche Einflüsse auf die Korrosionsbeständigkeit metallener Werkstoffe für Anlagenkomponenten. Der Vortrag beschreibt die Wechselwirkungen zwischen Geothermalwässern und Ausrüstungs-komponenten. T2 - Geothermiekongress 2024 CY - Potsdam, Germany DA - 22.10.2024 KW - Örtliche Korrosion KW - Edelstahl KW - Geothermie KW - Ni-Legierung KW - Abscheidung PY - 2024 AN - OPUS4-61441 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Geburtig, Anja A1 - Trubiroha, Peter A1 - Wachtendorf, Volker T1 - Significance of new data pairs for irradiance and (surface) temperature N2 - There is consent that UV irradiance and temperature at the place of photodegradation are the most important environmental parameters in weathering, along with humidity. This contribution shows how an improvement in the measurement data situation can improve the significance and comparability of outdoor exposures. Photooxidative ageing is calculated using sample polymers for which the corresponding modelling data (Exposure Response Functions, ERF) is available. The mean square deviations are estimated, which result from using different spectral irradiances and different spectral sensitivities, both of the sensors and the polymers. It will be shown here how the significance of the irradiance values increases with increasing approximation of the spectral sensitivities of the sensor and polymer. Also, the mean square deviations are estimated, which result from using different activation energies and surface temperatures. A selection of different variables to describe the weathering exposure is created. The potential of either individual values or data pairs is evaluated in terms of significance or correlation to the calculated photooxidative ageing. Recording hourly data also enables subsequent evaluations of individual test specimens, adapted to the respective colour or to determine activation energies. An accumulated value, calculated from PIT-radiometer irradiance and a suited surface temperature, can provide a comparison of different outdoor exposures over different locations or years. Thus, a characterisation of the weathering exposure would be related to a reference spectral sensitivity (much closer to a polymer than that of a common UV radiometer), one reference activation energy, and different surface temperature scenarios with, on the one hand, graded solar absorptions (white / grey / black) and, on the other hand, different thermal couplings (coated metal / thick plastic). This results in three values each for plastic samples and coated metals (light / grey / dark). It will never be possible to accurately predict the weathering tests for individual samples (with their specific sensitivities), but the proposed approaches can go a long way towards the comparability of outdoor weathering exposures. T2 - 10th European Weathering Symposium EWS CY - Graz, Austria DA - 11.09.2024 KW - Polymer 3R KW - Outdoor weathering PY - 2024 SN - 978-3-9826129-1-1 SP - 121 EP - 133 PB - Stober Medien GmbH CY - Eggenstein AN - OPUS4-61291 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Durlo Tambara, Luis Urbano A1 - Matos, P. R. de A1 - Lima, G. T. S. A1 - Silvestro, L. A1 - Rocha, J.C. A1 - Campos, C. E. M. de A1 - Gleize, P. J. P. T1 - Influence of Nanosilica and Superplasticizer Incorporation on the Hydration, Strength, and Microstructure of Calcium Sulfoaluminate Cement Pastes N2 - This study investigated the effect of incorporating three types of nanosilica (NS), two powders, and one colloidal suspension on the hydration, strength, and microstructure of calcium sulfoaluminate (CSA) cement pastes prepared with and without a superplasticizer (SP). X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy (SEM), and compressive strength tests were performed after 2, 5, and 28 days of hydration. The results showed that both NS powders delayed cement hydration at an early age, which was attributed to particle agglomeration (confirmed by dynamic light scattering). Whereas well-dispersed colloidal NS did not significantly affect the hydration of CSA at the investigated ages. SP incorporation improved the dispersion of CSA cement particles, resulting in a 10% increase in the degree of hydration of ye’elimite at 28 days for the system without NS. Conversely, when the SP was incorporated in NS-containing mixtures, it hindered cement hydration of the systems with powdered NS, but did not significantly affect the cement hydration of the system containing colloidal NS. The SEM images suggested that the SP changed the ettringite morphology, thereby negatively affecting the mechanical strength of the CSA pastes. KW - Calcium sulfoaluminate (CSA) cement KW - Nanosilica (NS) KW - Hydration KW - Microstructure PY - 2023 DO - https://doi.org/10.1061/JMCEE7.MTENG-15570 SN - 0899-1561 VL - 35 IS - 7 SP - 04023216 PB - ASCE AN - OPUS4-57404 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Erning, Johann Wilhelm A1 - Kamaraj, A. T1 - Susceptibility of 304 Stainless Steel to Crevice Corrosion in Electrochemically Active Fluids N2 - The susceptibility of Type 304 stainless steel (SS) to crevice corrosion upon contacting with electrochemically active fluids was investigated using exposure tests and stepwise potentiostatic polarization. Crevice materials made of 304 SS and polyether ether ketone (PEEK) were focused on in this study. The combined influence of oxidant and chloride concentration on crevice corrosion was examined in detail in the two types of crevice combinations (304 SS-to-PEEK and 304 SS-to-304 SS). The 304 SS specimens were strongly susceptible to crevice corrosion when coupled with 304 SS. Even at a low concentration of 5 mg/L free chlorine and 150 mg/L chloride, which is below nominal dilutions in beverage industries, the examined specimens underwent crevice corrosion in both crevices. The effect of water composition on crevice corrosion was also studied, indicating high susceptibility of 304 SS to crevice corrosion in low pH (pH ≤ 5) solutions. The corroded surface morphology was analyzed using scanning electron microscope, energy dispersive x-ray, and confocal. KW - Crevice corrosion KW - Disinfectants KW - Stainless steel PY - 2020 DO - https://doi.org/10.5006/3324 SN - 0010-9312 VL - 76 IS - 4 SP - 424 EP - 435 PB - Nace International CY - Houston AN - OPUS4-50652 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Bäßler, Ralph T1 - Rezension: Kurzlehrbuch Physikalische Chemie: für natur‐ und ingenieurwissenschaftliche Studiengänge N2 - Wem das Standardwerk der Physikalischen Chemie „Der Atkins“ zunächst zu überwältigend erscheint, dem gelingt mit diesem, nunmehr in der fünften Auflage erschienenen, Kurzlehrbuch sicherlich der Einstig in die Thematik. Studierenden im Bachelor‐ und Mastergang bietet es ein sehr hilfreiches Nachschlagewerk während des Studiums und zur Prüfungsvorbereitung. Die vielfältigen Übungen und Anwendungen am Ende jedes Kapitels, besser gesagt von jedem Fokus, tragen entscheidend zum Verständnis und Überprüfen des Gelernten bei. Sogenannte „Toolkits“ wiederholen an den entsprechenden Stellen inprägnanter Form mathematische Herangehensweisen und Techniken, die das Textverständnis unterstützen. Bei der Überarbeitung der vorherigen Ausgabe flossen nicht nur Anmerkungen von Lehrenden, sondern auch wertvolle Einblicke aus der Sicht der Lernenden, ein, was sich im Aufbau des Buches widerspiegelt. Dieses didaktisch und inhaltlich sehr gut aufgebaute Lehrbuch erfüllt auf jeden Fall seine Intension und weckt die Neugierde auf das im Frühjahr 2020 erscheinende dazugehörige Arbeitsbuch. KW - Elektrochemie KW - Korrosion PY - 2020 DO - https://doi.org/10.1002/maco.202070036 SN - 1521-4176 SN - 0947-5117 VL - 71 IS - 3 SP - 3 PB - WILEY‐VCH Verlag GmbH & Co. KGaA CY - Weinheim AN - OPUS4-50490 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Bäßler, Ralph T1 - Review: Nanopatterned and Nanoparticle‐Modified Electrodes N2 - Since nanoscience has a tremendous impact on the development of electrochemistry, Wiley‐VCH paid attention to that by publishing thisbook as volume 17 within the series “Advances in Electrochemical Science and Engineering”. This collection of “nanoaspects”on electrodes provides a helpful overview on principles and current findings to readers interested in such applications. It fulfills its intention of being “a valuable resource for researchers working in such fields as electrochemistry, materials science, spectroscopy, analytical and medicinal chemistry”. KW - Electrochemistry KW - Nanoparticle PY - 2020 DO - https://doi.org/10.1002/maco.202070014 SN - 1521-4176 SN - 0947-5117 VL - 71 IS - 1 SP - 179 EP - 180 PB - WILEY‐VCH Verlag GmbH & Co. KGaA CY - Weinheim AN - OPUS4-50205 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Bäßler, Ralph T1 - Review: Materials Handbook–A Concise Desktop Reference N2 - This concise reference book,consisting of 2 volumes, provides “key scientific and technical properties and data” for “materials scientists, metallurgists, engineers,chemists, and physicists as well as academic staff, technicians, and students” dealing with such kind of materials. Within its 3rd edition the previous work was extended by a chapter on occupational health and safety issues of materials, beside of the update of whole content. Within 22 chapters materials properties and data are summarized in many tables. Some facts are illustrated by drawings and diagrams for better understandability. Each chapter ends with a part on further reading arranged accordingly. KW - Corrosion KW - Materials KW - Corrosivity KW - Resistance PY - 2020 DO - https://doi.org/10.1002/maco.202070034 SN - 1521-4176 SN - 0947-5117 VL - 71 IS - 3 SP - 509 PB - WILEY‐VCH Verlag GmbH & Co. KGaA CY - Weinheim AN - OPUS4-50489 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - THES A1 - Babutzka, Martin T1 - Neue Erkenntnisse zur Deckschichtbildung von Zink an der Atmosphäre N2 - Die Korrosionsbeständigkeit und die Dauerhaftigkeit von Zink und Zinküberzügen an der Atmosphäre sind direkt mit der Bildungs- und Auflösungskinetik von schützenden Deckschichten aus festhaftenden Korrosionsprodukten verknüpft. Bei einem optimalen Zusammenwirken und einer günstigen Abfolge von atmosphärischen Einflussfaktoren bilden sich gut schützende, bei Feuchtigkeitszutritt nahezu unlösliche Deckschichten aus. Art und Eigenschaften der gebildeten Deckschichten hängen dabei insbesondere von den Luftinhaltsstoffen der Einsatzumgebung sowie von spezifischen Temperatur-Feuchte-Zyklen ab. Dabei besteht das Problem, dass sich die klimatischen Bedingungen und infolge auch die Deckschichtbildungsreaktionen bei Zink an der Atmosphäre im Laufe der letzten Jahrzehnte stark geändert haben. Das Ziel der vorliegenden Arbeit ist die systematische Untersuchung und Beschreibung von Korrosions- und Deckschichtbildungsvorgängen bei Reinzink unter den aktuell in der Bundesrepublik Deutschland vorherrschenden klimatischen Bedingungen. Die Untersuchungen zielen in ihrer Gesamtheit auf das Hinterfragen aktueller und die Etablierung neuer Betrachtungsweisen zur Deckschichtbildung bei Reinzink unter atmosphärischen Korrosionsbedingungen ab und sollen damit einen wesentlichen Beitrag für das Verständnis des Korrosionsschutzes durch Zink und Zinküberzüge liefern. Dabei wurde der Fokus insbesondere auf das Anfangsstadium der Deckschichtbildung gelegt. Eine systematische Untersuchung dieses Zeitraums, der von sehr reaktiven Deckschichten geprägt ist, wurde erst durch den gezielten Einsatz gelartiger Elektrolyte ermöglicht. KW - Zink KW - Korrosion KW - Deckschichtbildung KW - Atmosphäre KW - gelartige Elektrolyte PY - 2020 SN - 978-3-8440-7626-4 DO - https://doi.org/10.2370/9783844076264 SN - 0945-1056 SP - 1 EP - 181 PB - Shaker Verlag CY - Düren AN - OPUS4-51458 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Bäßler, Ralph T1 - Review: Corrosion of Linings and Coatings: Cathodic and Inhibitor Protection and Corrosion Monitoring N2 - This paperback issue of the 2007 hardcover version within the “Corrosion Engineering Handbook” series presents various materials and methods for controlling and protecting against corrosion instead of using expensive alloys to construct a tank or processing vessel. This book is a very comprehensive collection of the current knowledge about applied linings and coatings. So, it fulfills its intension, “that regardless of what is being built, … information for … whoever is responsible for the selection of material of construction will be found in this book to enable them to avoid unnecessary loss of material through corrosion”, to a very large extent. KW - Corrosion KW - Coating KW - Lining KW - Cathodic protection PY - 2020 DO - https://doi.org/10.1002/maco.202070104 SN - 1521-4176 SN - 0947-5117 VL - 71 IS - 10 SP - 1756 EP - 1757 PB - WILEY‐VCH Verlag GmbH & Co. KGaA CY - Weinheim AN - OPUS4-51414 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Langklotz, U. A1 - Babutzka, Martin A1 - Schneider, M. A1 - Burkert, Andreas T1 - The combination of minimally invasive electrochemical investigations and FTIR‐spectroscopy to analyze atmospheric corrosion product layers on zinc N2 - The present work describes the combination of electrochemical investigations by using a gel‐type electrolyte with Fourier‐transformed infrared spectroscopy to investigate partially extremely thin corrosion product films on titanium‐zinc. The gel pad method enables the determination of corrosion relevant parameters such as the potential and the linear polarization resistance without altering the corrosion product layers, which are extremely prone to re‐dissolution when freshly formed. Complementary infrared spectroscopy enables the determination of main compounds of even very thin surface layers of few tenth of nanometers with a certain lateral resolution. It was found that zinc forms mostly zinc carboxy‐hydroxides such as hydrozincite, under various exposure conditions. The protective properties of these hydrozincite layers depend on the structure of the corrosion product film rather than on its thickness. In mid‐term exposure tests, shallow corrosion pits were found even in the absence of corrosive agents such as chloride. KW - Gel-type electrolytes KW - Gelartige Elektolyte KW - Zinc coatings KW - Zinkdeckschichten KW - Korrosionsprüfung KW - Corrosion testing KW - FT-IR PY - 2019 DO - https://doi.org/10.1002/maco.201810696 SN - 0947-5117 SN - 1521-4176 VL - 70 IS - 7 SP - 1314 EP - 1325 PB - Wiley-VCH Verlag CY - Weinheim AN - OPUS4-47728 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Lehmann, Jens A1 - Burkert, Andreas A1 - Reinemann, Steffi A1 - Rother, D. T1 - Forschungsprojekt zum Korrosionsverhalten von Edelstählen - BAM und VSM mit neuen Erkenntnissen N2 - Wie kann man verhindern, dass Edelstahl korrodiert? Und welchen Einfluss haben Kornarten und Körnungen von Schleifmitteln auf das Korrosionsverhalten? Diesen Fragen ist die Bundesanstalt für Materialforschung und -prüfung (BAM) mit Unterstützung der VSM AG zwei Jahre lang auf den Grund gegangen. Heute wurden im VSM Technical Center am Hauptsitz von VSM in Hannover die Ergebnisse vorgestellt. Die zentralen Erkenntnisse: Kornarten und Zusätze im Schleifmittel haben keinen Einfluss auf die Korrosion. Aber: Je feiner die Oberfläche geschliffen ist, desto besser ist der Korrosionsschutz. Dabei ist das Einhalten der Schleiffolge besonders wichtig. KW - Nichtrostender Stahl KW - Korrosion KW - Schleifen KW - Korund PY - 2019 SN - 1430-0036 VL - 766 IS - 2 SP - 30 EP - 31 PB - Verlag Focus Rostfrei GmbH CY - Xanten AN - OPUS4-47607 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Weise, Frank T1 - AKR an Betonfahrbahndecken – ausgewählte Einflussgrößen und neuartige AKR-Vermeidungsstrategie N2 - In den letzten Jahren sind im deutschen Bundesautobahnnetz vermehrt Schäden an vor 2005 hergestellten Betonfahrbahndecken aufgetreten, die mit einer Alkali-Kieselsäure-Reaktion (AKR) in Verbindung gebracht werden. Vor diesem Hintergrund werden in diesem Beitrag zunächst die Voraussetzungen und ausgewählte Einflussgrößen für eine schädigende AKR aufgezeigt. Besondere Aufmerksamkeit wird dabei der Rolle des Tausalzeintrags durch den Winterdienst bei Betonfahrbahndecken geschenkt. So wird mit Löseversuchen in 1 M KOH-Lösung zweier Gesteinskörnungen bei 80 °C gezeigt, dass mit zunehmender NaCl-Zugabe die Löslichkeit von SiO2 zunimmt und die von Al2O3 eine Verminderung erfährt. Basierend auf dem so exemplarisch erbrachten Nachweis für die Verstärkung der schädigenden AKR durch das Tausalz wird die Notwendigkeit und Richtigkeit der Durchführung von AKR-Betonversuchen mit Alkalizufuhr im ARS 04/2013 zur zukünftigen Vermeidung von AKR-Schäden an Betonfahrbahndecken im Rahmen von Neubau- und Erneuerungsmaßnahmen im Bundesfernstraßennetz belegt. Zusätzlich durchgeführte WS-Grundprüfungen nach dem ARS 04/2013 mit den beiden Gesteinskörnungen der Löseversuche veranschaulichen, dass die nach der Alkali-Richtlinie des DAfStb als unbedenklich eingestuften Gesteinskörnungen bei den Betonversuchen mit Alkalizufuhr durchaus als alkaliempfindlich bewertet werden können. Dies wiederum führt zu einer Verminderung der für den Betonstraßenbau verfügba-ren Gesteinskörnungen. Vor diesem Hintergrund wird nach neuartigen AKR-Vermeidungsstrategien gesucht, die auch eine Verwendung der als grenzwertig alkaliemp-findlich eingestuften Gesteinskörnungen erlaubt. Einen möglichen Lösungsansatz stellt in diesem Kontext die Innenhydrophobierung des Fahrbahndeckenbetons dar. Es soll so durch die Behinderung des Feuchte- und Tausalzeintrags in den Beton der AKR-Schädigungsprozess signifikant vermindert werden. Für die Bewertung der Leistungsfähigkeit der Innenhydrophobierung zur Vermeidung bzw. Verminderung einer schädigenden AKR in Betonfahrbahndecken wird zurzeit im Auftrage der BASt an der BAM ein Forschungsvorha-ben bearbeitet. Im Rahmen dieses Beitrags werden erste Ergebnisse dieses Projekts vorge-stellt. So wird exemplarisch an einem Oberbeton (D > 8)/Unterbeton und einem Oberbeton 0/8 mit einer alkaliempfindlichen Gesteinskörnung der Einfluss zweier Hydrophobierungsmit-tel auf die Frisch- und Festbetoneigenschaften ganzheitlich aufgezeigt und bewertet. Bei Letz-teren stehen zunächst die mechanischen und hygrischen Parameter sowie der Frost-Tausalzwiderstand im Vordergrund. In einem weiteren Schritt wird der Einfluss beider Hydro-phobierungsmittel auf die schädigende AKR mittels AKR-Betonversuchen mit Alkalizufuhr beleuchtet. Dabei gelangen ergänzend zur Beurteilung des Tausalzeintrags die Laser-Induced Breakdown Spectroscopy (LIBS) und zur Bewertung der Ausprägung der AKR und sekundä-ren Ettringitbildung (SEB) die Dünnschliffmikroskopie zum Einsatz. T2 - 9. Betonfachtagung CY - Berlin, Germany DA - 12.11.2019 KW - AKR, Betonfahrbahndecke, Tausalzeintrag, Innenhydrophobierung PY - 2019 SN - 978-3-7640-0633-4 SP - 159 EP - 175 PB - Verlag Bau + Technik GmbH CY - Erkrath AN - OPUS4-51563 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Lehmann, Jens T1 - Der KorroPad Korrosions-Schnelltest Einfach, schnell, zerstörungsfrei N2 - Eine kurze Einführung in den KorroPad test. Kombiniert mit einer praktischen Vorführung. T2 - Tag der Technik, Romain-Rolland-Gymnasium CY - Berlin, Germany DA - 16.07.2024 KW - Korrosion KW - Experimente KW - KorroPad PY - 2024 AN - OPUS4-60664 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Recknagel, Christoph T1 - Dauerhafte Funktionsfähigkeit von Bauwerksfugen – Das Performance-concept in der Abdichtungstechnik von Betonfahrbahnen N2 - Verlässliche Funktionsfähigkeit und planbare Lebensdauerzyklen sind entscheidend für die Weiterentwicklung der Betonbauweise im Straßenbau. Aus Forschungsergebnissen zur Fugenproblematik in hochbeanspruchten Betonfahrbahnen unter Diskussion regelungsspezifischer Erfordernisse erfolgt ein Plädoyer für eine funktionsanalytische Untersuchung von Fugensystemen. Mit aktuellen Projekten werden die Datengrundlage zu maßgebenden Einwirkungen und eine innovative versuchstechnische Infrastruktur als methodische Voraussetzungen zur Erhöhung zuverlässiger Funktionsfähigkeit von Bauwerksfugen bereitgestellt T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM Green Intelligent Building CY - Berlin, Germany DA - 16.10.2024 KW - Nachhaltige Verkehrsinfrastruktur KW - Dauerhafte Betonfahrbahnen KW - Performance-concept KW - Kenngrößenermittlung in-situ KW - Versuchseinrichtung PY - 2024 AN - OPUS4-61465 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - BOOK A1 - Schoch, R. A1 - Schartel, Bernhard A1 - Wachtendorf, Volker A1 - Tan, Yi A1 - Lin, Xuebao A1 - Tröppner, O. A1 - Lang, M. A1 - Hochrein, T. A1 - Bastian, M. T1 - Langzeit- und Witterungsstabilität von halogenfreiem Flammschutz in Polymeren N2 - Die Forderung, dass der Flammschutz von Kunststoffen nicht nur zum bei der Herstellung der jeweiligen Produkte, sondern auch über die gesamte Einsatzdauer im geforderten Maß wirksam ist, stellt eine große Aufgabe dar. Ferner ist die Anforderung für viele Produkte in der Praxis neu, da bisher vor allem der Einfluss der Flammschutzmittel auf die Stabilität der Polymerwerkstoffe, nicht aber die Stabilität des Flammschutzes untersucht wurde. Das Langzeitverhalten halogenfreier Systeme ist bis heute wenig untersucht, insbesondere weil Phosphor- und Stickstoff-basierte Systeme die oxidative Beständigkeit von Polymeren weniger zu beeinflussen scheinen als halogenhaltige FSM. Die Frage, wie zuverlässig der Flammschutz wirkt, wenn Kunststoffe einige Jahre im Innen- und Außenbereich im Einsatz sind und dabei wechselnden Beanspruchungen ausgesetzt waren, wurde bislang nur vereinzelt untersucht. Mögliche Auswirkungen von Witterungseinflüssen auf flammgeschützte Polymerwerkstoffe sind, dass die Flammschutzmittel selbst abbauen, ausgewaschen werden, oder auch durch Wechselwirkung mit den eingesetzten Additiven oder mit den Alterungsprodukten der Polymermatrix in ihrer Wirkung nachlassen. Hier bestand großer Forschungsbedarf, um an den Punkt zu gelangen, die Beständigkeit der Flammschutzeigenschaften eines Produktes über seine gesamte Lebensdauer zuverlässig garantieren zu können. Diese Fragestellung greift das durchgeführte Forschungsvorhaben auf. Ziel war die Untersuchung der Langzeitstabilität der Flammschutzwirkung von halogenfrei flammgeschützten Polymerwerkstoffen unter diversen Witterungseinflüssen. Dazu wurden die Schädigungsmechanismen der Polymerwerkstoffe und der Flammschutzmittel sowie die auftretenden Wechselwirkungen analysiert, um ein Verständnis für die ablaufenden Prozesse zu entwickeln und Empfehlung für die Reduzierung der Alterung zu erarbeiten. Gegenstand der Untersuchungen waren anwendungsrelevante Flammschutz-Konzepte, die miteinander verglichen wurden. Die Erarbeitung von Struktur-Eigenschafts-Beziehungen ermöglichte die Beschreibung der Empfindlichkeiten und den Vergleich zwischen den Systemen. Darauf basierend wurden für die FSM spezifische Leitlinien für die Optimierung der Langzeitstabilität des Flammschutzes erstellt. N2 - The requirement that the flame retardancy of plastics is still effective to the required degree not only at the time of manufacture of the respective products, but also over the entire period of use, is a major challenge in view of the very long periods of time involved. In addition, the requirement is new for many products in practice, as up to now the influence of flame retardants on the stability of the polymer materials has been investigated, but not the stability of the flame retardant itself. The long-term behaviour of halogen-free systems has been little studied to date, especially because phosphorus- and nitrogen-based systems seem to have a much smaller influence on the oxidative stability of polymers than halogene containing flame retardants. The question of how reliable flame retardancy is when plastic products have been in use for several years indoors and outdoors and have been exposed to a wide range of climatic stresses has only been investigated in isolated cases. Possible effects of weathering on flame-retarded polymer materials are that the flame retardants themselves degrade, migrate or are washed out, or that their effect diminishes through interaction with other additives used or with the ageing products of the polymer matrix. At this point, there was a great need for research in order to reach the point where the stability of the flame retardant properties of a product can be reliably guaranteed over its entire service life. This question is taken up by the research project carried out. The aim of the research project was the systematic investigation of the long-term stability of the flame-retardant effect of halogen-free flame-retardant polymer materials under various weather conditions. For this purpose, the predominant damage mechanisms of the polymers and the flame retardants as well as the interactions occurring were analysed in order to develop an understanding of the processes taking place and to work out recommendations for reducing ageing. Subject of the investigations were different applicationrelevant flame retardant concepts, which were compared with each other. The development of structure-property relationships enabled the description of the specific sensitivities and the comparison between the different systems. Based on this, specific guidelines for the optimisation of the long-term stability of the flame retardants were developed for the different flame retardants. KW - Durability KW - Flame retardant KW - Flammschutz KW - Weathering KW - Ethylene-vinyl acetate KW - Cables KW - Polyamid KW - Langzeitstabilität PY - 2021 SN - 978-3-8440-7781-0 SN - 2364-754X SP - 1 EP - 222 PB - Shaker CY - Düren AN - OPUS4-54274 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Erning, Johann Wilhelm T1 - Neues von der Bundesanstalt für Materialforschung und –prüfung N2 - Es werden ausgewählte Folien aus der Standard-BAM-Präsentation gezeigt, im Anschluss daran die besonderen Kompetenzen des Fachbereichs 7.6. Dort wird insbesondere auf Anknüpfungspunkte zu Infrastruktur (Leitungen, Brücken,…) abgestellt. T2 - Sitzung DVGW-Landesgruppe Berlin-Brandenburg CY - Potsdam, Germany DA - 21.04.2024 KW - Kompetenzen KW - BAM KW - Korrosion PY - 2024 AN - OPUS4-61841 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Battig, Alexander A1 - Garfias González, Karla I. A1 - Schartel, Bernhard T1 - Valorizing “non-vegan” bio-fillers: Synergists for phosphorus flame retardants in epoxy resins N2 - Sustainable, biogenic flame retardant adjuvants for epoxy resins are receiving increased focus. Zoological products like insects, bone meal, and eggshells are available in large quantities, but remain uninvestigated as functional fillers to epoxy resins, although they are potential synergists to flame retardants. The efficacy and flame retardancy of “non-vegan” additives in combination with flame retardants is investigated and the fire behavior and thermal decomposition of bio-sourced epoxy resin composites is characterized. By comparing the fire performance of composites containing flame retardants or fillers at varying loadings (5, 10, and 20%), their role as synergists that enhance the function of organophosphorus flame retardants in bio-epoxy composites is identified and quantified. Peak heat release rates were 44% lower in composites containing both filler and flame retardant versus those containing only flame retardants, and fire loads were reduced by 44% versus the pure resin, highlighting the ability of “non-vegan” fillers to function as synergists. KW - Flame retardancy KW - Synergy KW - Bio-composite KW - Epoxy resin KW - Biogenic KW - Renewable PY - 2022 DO - https://doi.org/10.1016/j.polymdegradstab.2022.109875 SN - 0141-3910 VL - 198 SP - 109875 PB - Elsevier Ltd. AN - OPUS4-54438 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - von Werder, Julia T1 - Hydrothermal Treatment of Ultra-High-Performance Concrete: Mechanical Propertoes and Phase Composition N2 - The advantages of treating prefabricated components made of Ultra-High-Performance Concrete (UCPC) at 90 °C are largely recognized, while hydrothermal treatment at 185 °C and the corresponding saturation pressure of 1.1 MPa, in contrast, is not applied in building practice so far and was studied only by a few researchers. In the research presented, the parameters pre-storage-time before treatment and dwell time in the autoclave were systematically varied. The results illustrate in which way compressive strength increases with the duration of treatment. Already samples which were only heated up and immediately cooled down show an increase in strength compared to the 28-day reference of about 10 %. After 20 h the maximum increase of about 25 % is reached. Interestingly the compressive strength of samples treated very long hardly decreases. It can be therefore concluded that for the composition investigated the achievable mechanical strength is not severely sensitive regarding the duration of the treatment. Also, pre-storage times before autoclaving longer than 0.5 days showed no significant impact on strength development. The phase composition measured by XRD exhibits significant changes compared to the reference. The amount of ettringite and portlandite have vanished, the cement clinker phases are substantially decreased and hydroxylellestadite and hydrogarnet are formed as new phases. The increase in strength can be assigned to an improved pozzolanic and hydraulic reaction. Contradictory to literature, there was found no obermorite, a mineral which is known to be susceptible for disintegration at Long autoclaving duration. This explains why no significant strength loss appeared. T2 - 15th International Congress on the Chemistry of Cement CY - Prague, Czech Republik DA - 16.09.2019 KW - Hydrothermal treatment KW - UHPC KW - Phase composition KW - Mechanical strength PY - 2019 AN - OPUS4-49469 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Andrés Arcones, Daniel A1 - Weiser, M. A1 - Koutsourelakis, P.-S. A1 - Unger, Jörg F. T1 - Model bias identification for Bayesian calibration of stochastic digital twins of bridges N2 - Simulation-based digital twins must provide accurate, robust, and reliable digital representations of their physical counterparts. Therefore, quantifying the uncertainty in their predictions plays a key role in making better-informed decisions that impact the actual system. The update of the simulation model based on data must then be carefully implemented. When applied to complex structures such as bridges, discrepancies between the computational model and the real system appear as model bias, which hinders the trustworthiness of the digital twin and increases its uncertainty. Classical Bayesian updating approaches aimed at inferring the model parameters often fail to compensate for such model bias, leading to overconfident and unreliable predictions. In this paper, two alternative model bias identification approaches are evaluated in the context of their applicability to digital twins of bridges. A modularized version of Kennedy and O'Hagan's approach and another one based on Orthogonal Gaussian Processes are compared with the classical Bayesian inference framework in a set of representative benchmarks. Additionally, two novel extensions are proposed for these models: the inclusion of noise-aware kernels and the introduction of additional variables not present in the computational model through the bias term. The integration of these approaches into the digital twin corrects the predictions, quantifies their uncertainty, estimates noise from unknown physical sources of error, and provides further insight into the system by including additional pre-existing information without modifying the computational model. KW - Gaussian process KW - KOH KW - Bayesian updating KW - Digital twins KW - Uncertainty quantification PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-615519 DO - https://doi.org/10.1002/asmb.2897 SN - 1526-4025 N1 - This work was supported by “C07 - Data driven model adaptation for identifying stochastic digital twins of bridges” from the Priority Program (SPP) 2388/1 “Hundred plus” of the German Research Foundation (Deutsche Forschungsgemeinschaft, DFG) - Project number 501811638. VL - 417 IS - 3 SP - 1 EP - 26 PB - Wiley CY - Chichester AN - OPUS4-61551 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Weigel, Sandra A1 - Sielaff, S. A1 - Kunsic-Nowak, T. A1 - Nytus, N. A1 - Schwettmann, K. A1 - Schulze, C. A1 - Wetekam, J. T1 - Die FTIR-Untersuchung von Bitumen: Chancen, Durchführung und Präzision N2 - Die Fourier-Transformations-Infrarot-Spektroskopie (FTIR-Spektroskopie) stellt eine innovative und wirkungsvolle Methode zur Charakterisierung von Bitumen und bitumenhaltigen Bindemitteln dar. So erlaubt die FTIRCharakterisierung nicht nur eine Bewertung des Alterungsfortschritts eines Bindemittels, sondern zudem auch die Identifizierung von im Bitumen enthaltenen Additiven und Schadstoffen wie z. B. polyzyklischen aromatischen Kohlenwasserstoffen (PAK), die Ableitung verschiedener physikalischer und chemischer Kennwerte sowie weiterhin eine Klassifizierung von Bindemitteln nach verschiedenen übergeordneten Eigenschaften wie der Raffinerie, dem Alterungszustand und auch der Alterungsempfindlichkeit. KW - Bitumen und bitumenhaltige Bindemittel KW - FTIR-Spektroskopie KW - Anwendungsmöglichkeiten KW - Vergleichuntersuchung KW - Arbeitsanleitung KW - Präzision PY - 2023 UR - https://www.kirschbaum.de/fachzeitschriften/strasse-und-autobahn/strasse-und-autobahn/aktuelles-heft-17.html DO - https://doi.org/10.53184/STA8-2023-4 VL - 74/8 SP - 630 EP - 642 PB - KIRSCHBAUM VERLAG GmbH CY - Bonn AN - OPUS4-59049 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bhuyan, Md Delwar Hossain A1 - Döhler, M. A1 - Lecieux, Y. A1 - Lupi, C. A1 - Thomas, J. A1 - Schoefs, F. A1 - Hille, Falk A1 - Mevel, L. T1 - Statistical Subspace-based Damage Localization on Saint-Nazaire Bridge Mock-Up N2 - The subject of damage localization is an important issue for Structural Health Monitoring (SHM) particularly in mechanical or civil structures under ambient excitation. In this paper, the statistical subspacebased damage localization method has been applied on a benchmark application, namely a 1/200 scale model of the Saint-Nazaire Bridge, which is a cable-stayed bridge located on the Loire River near the river’s mouth. The employed damage localization method combines data-driven features with physical parameter information from a finite element model in statistical tests, avoiding typical ill-conditioning problems of FE model updating. Damage is introduced in the mockup for cable failures on some of the 72 cables. The purpose of the experiment is to assess the capability of damage assessment methods to find a cable failure. T2 - International Operational Modal Analysis Conference CY - Copenhagen, Danmark DA - 13.05.2019 KW - Structural health monitoring KW - Damage localization KW - Cable-stayed bridge KW - Cable failure PY - 2019 SP - 1 EP - 9 AN - OPUS4-48243 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Eilers, M. A1 - Alte-Teigeler, R. A1 - Borchers, R. A1 - Gallai, G. A1 - Habiger, D. A1 - Recknagel, Christoph A1 - Karczewski, B. A1 - Koll, J. A1 - Lorenz, S. A1 - Marossow, H. A1 - Schneider, Th. A1 - Seiffart, J. A1 - Stark, S. A1 - et al., T1 - Technische Prüfvorschriften für Fahrbahnübergänge aus Asphalt, TL/TP-ING - Teil 6, Abschnitt 7 N2 - Technische Lieferbedingungen und Technische Prüfvorschriften für Ingenieurbauten KW - Brückenbeläge KW - Asphaltbauweisen KW - Fahrbahnübergänge PY - 2022 SN - 978-3-86446-343-3 VL - 780/3 SP - 1 EP - 26 PB - FGSV Verlag GmbH CY - Köln AN - OPUS4-56218 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schilling, Markus T1 - An optical criterion for the assessment of Full-Notch Creep Test (FNCT) fracture surfaces N2 - The full-notch creep test (FNCT) is a common method to evaluate the environmental stress cracking (ESC) behavior of high-density polyethylene (PE-HD) container materials . The test procedure as specified in ISO 16770 provides a comparative measure of the resistance against ESC using the time to failure of specimens mechanically loaded in a well-defined liquid environment. Since the craze-crack damage mechanism underlying the ESC process is associated with brittle failure, the occurrence of globally brittle fracture surfaces is a prerequisite to consider an FNCT measurement as representative for ESC . Therefore, an optical evaluation of FNCT fracture surfaces concerning their brittleness is essential. Due to the experimental setup, an inevitable increase of the true mechanical stress and the associated appearance of small ductile parts on fracture surfaces is induced in any case. Hence, an FNCT experiment is considered as 'valid', if the corresponding fracture surface is predominantly brittle . Based on laser scanning microscopy (LSM) height data of FNCT fracture surfaces , a universal and easy-to-use phenomenological criterion was developed to assess the validity of distinct FNCT experiments. This criterion is supposed to facilitate a quick evaluation of FNCT results in practical routine testing. T2 - PPS Europe-Africa 2019 Regional Conference (PPS 2019) CY - Pretoria, South Africa DA - 18.11.2019 KW - Full-Notch Creep Test (FNCT) KW - Polyethylene, PE-HD KW - Fracture surface analysis KW - Environmental stress cracking (ESC) KW - Optical criterion KW - Brittle fracture PY - 2019 AN - OPUS4-50940 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Bäßler, Ralph T1 - Review: Biofuels: Alternative Feedstocks and Conversion Processes for the Production of Liquid and Gaseous Biofuels N2 - his fully updated examination of sustainable processes for gaseous and liquid biofuels production, published for the second time within the series “Biomass, Biofuels, Biochemicals”, provides 33 contributions made by 120 authors. They present a holistic view of biofuels in research, operation, scale‐up and application. Comparing to the first edition, all chapters have been updated and new chapters covering topics of current interest, including sustainability and biohydrogen have been added. By its wide overview on existing technologies, this book provides state‐of‐the‐art information and knowledge to the desired readership, like post‐graduates, researchers in the area of biofuels, wastewater treatment, alternate energy sources, renewable energy from biomass, chemical and biochemical engineers, microbiologists, biotechnologists working in academic and research institutes as well as in industry and governmental agencies. KW - Biofuel PY - 2020 DO - https://doi.org/10.1002/maco.202070074 SN - 1521-4176 SN - 0947-5117 VL - 71 IS - 7 SP - 1230 EP - 1231 PB - WILEY‐VCH Verlag GmbH & Co. KGaA CY - Weinheim AN - OPUS4-50961 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Strommer, Bettina A1 - Battig, Alexander A1 - Frasca, Daniele A1 - Schulze, Dietmar A1 - Huth, Christian A1 - Böhning, Martin A1 - Schartel, Bernhard T1 - Multifunctional Property Improvements by Combining Graphene and Conventional Fillers in Chlorosulfonated Polyethylene Rubber Composites N2 - The incorporation of nanoparticles like multilayer graphene (MLG) into elastomeric composites boosts their technical performance, such as their mechanical behavior and electrical conductivity. Common filler types (carbon black (CB) and aluminum trihydroxide (ATH)) generally fulfill single, specific purposes and are often used in high loadings. CB typically reinforces rubber mechanically, while ATH increases flame retardancy. Small amounts of MLG reduce these high filler contents and maintain the multifunctional characteristics of rubber composites. In chlorosulfonated polyethylene (CSM) + ATH, an intrinsically flame-retardant rubber was designed to achieve the highest standards such as maximum average of heat emission (MARHE) <90 kW m−2, 3 phrMLG was substituted for 15 phr CB and/or 3 phr ATH via an industrially applicable processing approach. Replacing either CB or ATH resulted in a property profile that was multifunctionally improved in terms of features such as mechanical performance, reduced sorption, and flame retardance. MLG nanocomposites are reported to show promise as an industrially utilizable route to obtain multifunctional high-performance rubbers. KW - Nanocomposites KW - Rubber KW - Multilayer graphene KW - Flame retardancy KW - Synergy KW - Nanoparticles KW - Elastomers PY - 2022 DO - https://doi.org/10.1021/acsapm.1c01469 SN - 2637-6105 VL - 4 IS - 2 SP - 1021 EP - 1034 PB - ACS Publ. CY - Washington, DC AN - OPUS4-54330 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Eichner, Lukas A1 - Schneider, Ronald A1 - Baeßler, Matthias T1 - Optimal vibration sensor placement for jacket support structures of offshore wind turbines based on value of information analysis N2 - Information on the condition and reliability of an offshore jacket structure provided by a vibration-based structural health monitoring system can guide decisions on inspection and maintenance. When selecting the sensor setup, the designer of the monitoring system must assess its overall benefit compared to its costs before installation. The potential benefit of continuously monitoring the dynamic response of a jacket structure can be formally quantified through a value of information analysis from Bayesian decision theory. In this contribution, we present a framework for optimizing the placement of vibration sensors on offshore jacket structures by maximizing the value of information of the monitoring system. To solve the resulting discrete optimization problem, we adapt a genetic algorithm. The framework is demonstrated in a numerical example considering a redundant jacket-type steel frame. The numerical study shows that monitoring the vibration response of the frame is beneficial. Good sensor setups consist of relatively few sensors located towards the upper part of the frame. The adapted genetic algorithm performs similarly well as established sequential sensor placement algorithms and holds substantial promise for application to real jacket structures. KW - Optimal sensor placement KW - Value of information KW - Jacket support structure KW - Offshore wind turbine KW - Monitoring-informed inspection and maintenance planning PY - 2023 DO - https://doi.org/10.1016/j.oceaneng.2023.115407 SN - 0029-8018 VL - 288 IS - 2 PB - Elsevier Ltd. CY - Amsterdam AN - OPUS4-58725 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wallau, Wilma A1 - Recknagel, Christoph T1 - Test methodology for performance assessment of structural sealant glazing systems at superimposed mechanical and climatic loading N2 - Reliable performance of structural sealant glazing (SSG) systems is necessary to utilise advantages of SSG in glass facades. Conventional durability assessment of structural sealant joints is based on separated weathering tests and empirical fatigue testing. This work presents a new test methodology for performance assessment of SSGjoints at simultaneous weathering and two-dimensional mechanical loading. The climatic and mechanical load function were derived from common loading scenarios according to a worst case approach. A System test specimen, resembling a common SSG-joint, was exposed to 24 h of combined loading in a custom-designed test facility. From the recorded mechanical system response, characteristic parameters were evaluated to assess the performance of the system at varying climatic and mechanical conditions. These experimental results reveal effects of ambient conditions, previous loading and deformation Amplitude peaks on the system response. The proposed test methodology opens up for new performance-related approaches in durability testing. KW - Structural sealant glazing KW - Performance assessment KW - Durability testing KW - Hysteresis measurement KW - Superimposed loading PY - 2019 DO - https://doi.org/10.1016/j.polymertesting.2019.106030 SN - 0142-9418 VL - 79 SP - 106030, 1 EP - 15 PB - Elsevier AN - OPUS4-48871 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CHAP A1 - Oliveira, C. A1 - Silveira, D. A1 - Varum, H. A1 - Parisi, F. A1 - Miccoli, Lorenzo A1 - Solis, M. A1 - Rodriguez-Mariscal, J. D. A1 - Tarque, N. ED - Varum, H. ED - Parisi, F. ED - Tarque, N. ED - Silveira, D. T1 - Mechanical Characterization of Adobe Masonry N2 - The characterization of the mechanical properties and behaviour of adobe masonry is fundamental for the understanding of the structural behaviour of adobe constructions. Thus, in the last decades, experimental studies focused on this topic have been carried out by different authors. Many of the existing experimental works, however, were carried out aiming to support broader studies focused on the seismic behaviour of adobe constructions and are not very detailed. Moreover, authors tend to adopt different procedures in their experimental work, since there are few indications in existing standards for testing adobe masonry. The wide variety in materials used, both for the adobes and mortars, further complicates this work, making it difficult to compare results obtained in different studies. This chapter provides an overview of the indications given by standards and other technical recommendations for the mechanical testing of adobe masonry. It presents a review of existing research on the mechanical behaviour of adobe masonry, addressing studies that focus on: (i) compression behaviour, (ii) shear behaviour, (iii) joint shear behaviour. It provides a global analysis of the existing knowledge, suggesting improvements for normative documents and identifying future Research needs. KW - Adobe masonry KW - Mechanical behaviour KW - Experimental tests KW - Standards PY - 2021 SN - 978-3-030-74736-7 DO - https://doi.org/10.1007/978-3-030-74737-4_4 SN - 2194-9832 VL - 20 SP - 55 EP - 92 PB - Springer Nature Switzerland AG AN - OPUS4-54171 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CHAP A1 - Silveira, D. A1 - Oliveira, C. A1 - Varum, H. A1 - Ioannou, I. A1 - Miccoli, Lorenzo A1 - Tarque, N. A1 - Parisi, F. A1 - Fenu, L. A1 - Solis, M. A1 - Rodriguez-Mariscal, J. D. ED - Varum, H. ED - Parisi, F. ED - Tarque, N. ED - Silveira, D. T1 - Mechanical Characterization of Adobe Bricks N2 - The mechanical characterization of adobe bricks is an important first step in the study of the behaviour of adobe masonry. For this reason, in the last decades, different authors have conducted research on the mechanical behaviour of adobes from various regions of the world. Despite the importance of mechanical characterization, there are still only a few standards and normative documents with clear indications for the mechanical testing of earthen materials and, in general, These indications are not thorough and vary among different countries. Consequently, authors tend to adopt different types of test specimens and procedures in their experimental work, thus obtaining results that are not directly comparable. The fact that the materials and procedures traditionally used are also not standardized,varying greatly from region to region, also contributes to the difficulty of comparing results from different studies. This chapter presents a review of the indications provided by codes, standards and other technical recommendations for the mechanical testing of adobe bricks, as well as a detailed review of procedures adopted, and results obtained by different authors regarding the mechanical characterization of traditional adobe bricks. This chapter focuses, in particular, on the behaviour of adobe bricks when subjected to simple compression. It provides an overview of the existing knowledge and identifies needs for future research and development. KW - Adobe KW - Adobe masonry KW - Mechanical behaviour KW - Test procedures KW - Standards PY - 2021 SN - 978-3-030-74736-7 DO - https://doi.org/10.1007/978-3-030-74737-4 SN - 2194-9832 VL - 20 SP - 35 EP - 54 PB - Springer Nature Switzerland AG AN - OPUS4-54170 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Stoljarova, A. A1 - Regenspurg, S. A1 - Bäßler, Ralph A1 - Mathiesen, T. A1 - Braüner Nielsen, J. T1 - Effect of lead and copper containing brine on steel materials for geothermal applications – A corrosion study N2 - Geothermal brines often contain high amounts of lead and copper ions that can precipitate as native Cu and Pb as consequence of galvanic corrosion when brines react with carbon steel materials. This contribution evaluates which materials could overcome the problem of galvanic corrosion at geothermal environment. The behavior of these materials in water containing high chloride concentration (> 100 g/L NaCl) as well as various amounts of dissolved bCl2 and/or CuCl2 was characterized by electrochemical and exposure measurements. Both methods reveal carbon steel suffers corrosion susceptibility, accompanied by Cu◦ and/or Pb◦ precipitation on the surface. Electrochemical measurements on stainless steels result in significant difference in corrosion and repassivation potentials (Ecorr = -189 mV, Erep = 70 mV), indicating a good corrosion resistance. KW - Copper KW - Lead KW - Corrosion KW - Steel KW - Geothermal energy PY - 2021 DO - https://doi.org/10.1016/j.geothermics.2020.102024 SN - 0375-6505 VL - 91 SP - NIL_75 EP - NIL_85 PB - Elsevier CY - Amsterdam AN - OPUS4-51976 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Aristia, Gabriela A1 - Le, Quynh Hoa A1 - Bäßler, Ralph T1 - Electrochemical deposition of polyaniline on carbon steel for corrosion study in geothermal solution N2 - Polyaniline has been widely developed for many applications, e.g. sensor, supercapacitor components, electrochromic devices, and anticorrosion pigments. Although the addition of polyaniline pigment in organic coatings has been an alternative for corrosion protection in industrial applications, the protection mechanism is still not fully understood. Herein in this study, as a part of the development of polyaniline/silicon dioxide coating for geothermal application, polyaniline has been deposited electrochemically on carbon steel surface in oxalic acid medium and tested in geothermal solution to understand the contribution of polyaniline to the corrosion protection of a polyaniline-based composite in the geothermal system. To observe the surface/interface reaction between the electrolyte and electrode surface during the electrochemical polymerization, electrochemical impedance spectroscopy (EIS) was applied after each cycle. For corrosion study in the geothermal application, an artificial geothermal solution was used with the composition of 1,500 mg/l Cl⁻, 20 mg/l SO₄²⁻, 15 mg/l HCO₃⁻, 200 mg/l Ca²⁺, 250 mg/l K⁺, and 600 mg/l Na⁺, and pH 4 to simulate a geothermal brine found in Sibayak, Indonesia. An electrochemical measurement was performed by monitoring the open circuit potential over seven days, with the interruption by EIS every 22 hours. The experiments were performed at room temperature and 150 °C (1 MPa) in an oxygen-free environment. Impedance spectra showed a reduction of the total impedance value of approximately 10 times for specimens measured at 150 °C compared to the specimens measured at room temperature, suggesting a less stable layer at high temperature. KW - Corrosion KW - Electrochemical deposition KW - Polyaniline PY - 2019 DO - https://doi.org/10.4028/www.scientific.net/MSF.966.107 SN - 1662-9752 VL - 966 SP - 107 EP - 115 PB - Trans Tech Publications Ltd CY - Zürich AN - OPUS4-48776 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Strommer, Bettina T1 - Natural Rubber Nanocomposites via Optimized Latex Premixing and Conventional Technical Processing N2 - Creation of highly functional materials and replacement of high amounts of conventional fillers are driving forces for the development of nanocomposites. Besides the type and properties of nanoparticles, their dispersing in the elastomeric matrix and the stability of this dispersion through all processing steps are the main factors for the resulting performance of the produced material. Therefore, a preparation chain via latex premixing to a highly filled masterbatch, followed by conventional technical processing is to be developed. Three types of carbon-based particles are characterized as such (SEM, Raman Spectroscopy, BET specific surface area) and in combination with natural rubber, as nanocomposites (TEM. Hardness, Abrasion resistance, Compression set, Cone calorimetry). All of the studied particles lead to an improvement in the investigated mechanical properties, the extent of reinforcement depends strongly on the specific surface of the particle interacting with the elastomeric matrix in combination with their shape. T2 - DKG Elastomer Symposium CY - Online meeting DA - 28.06.2021 KW - Processing KW - Elastomers KW - Nanocomposites KW - Graphene KW - Nanoparticles KW - Latex KW - Natural rubber PY - 2021 AN - OPUS4-53106 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Battig, Alexander T1 - Multifunctional Graphene in Flame Retarded Polybutadiene/ Chloroprene/ Carbon Black Composites N2 - Multilayer graphene is investigated as a multifunctional nanofiller to polybutadiene/ chloroprene rubbers (BR/CR) that partially substitutes carbon black (CB) and aluminum trihydroxide (ATH). Loadings of only 3 parts per hundred rubber (phr) MLG replaced 15 phr of CB and/or 3 phr of ATH in BR/CR nanocomposites. Mechanical and fire behavior were investigated, and results point to improved rheological, curing and mechanical properties of MLG-containing rubber composites. T2 - 18th European Meeting on Fire Retardant Polymeric Materials, FRPM21 CY - Budapest, Hungary DA - 29.08.2021 KW - Graphene KW - Rubber KW - Fire Retardant KW - Nanofiller KW - Nanocomposite KW - ATH PY - 2021 AN - OPUS4-53202 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Artinov, Antoni T1 - Modeling the Relationship between Weld Pool Dynamics and Centerline Solidification Cracking in High Power Laser Beam Welding N2 - The present work deals with the recently confirmed widening of the weld pool interface, known as a bulging effect, and its relevance in high power laser beam welding. A combined experimental and numerical approach is utilized to study the influence of the bulge on the hot cracking formation and the transport of alloying elements in the molten pool. A technique using a quartz glass, a direct-diode laser illumination, a high-speed camera, and two thermal imaging cameras is applied to visualize the weld pool geometry in the longitudinal section. The study examines the relevance of the bulging effect on both, partial and complete penetration, as well as for different sheet thicknesses ranging from 8 mm to 25 mm. The numerical analysis shows that the formation of a bulge region is highly dependent on the penetration depth and occurs above 10 mm penetration depth. The location of the bulge correlates strongly with the cracking location. The obtained experimental and numerical results reveal that the bulging effect increases the hot cracking susceptibility and limits the transfer of alloying elements from the top of the weld pool to the weld root. T2 - Gastvortrag an der Universität Innsbruck, Institut für Konstruktion und Materialwissenschaften CY - Innsbruck, Austria DA - 18.06.2023 KW - Laser beam welding KW - Centerline solidification cracking KW - Bulging KW - Numerical simulation PY - 2024 AN - OPUS4-60333 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Krütt, Enno A1 - Weise, Frank A1 - Meng, Birgit T1 - Einfluss einer druckschwellinduzierten Degradation von Fahrbahndeckenbeton auf die schädigende AKR T1 - Influence of cyclic compressive loading induced degradation of road pavement concrete on harmful AAR N2 - In den letzten Jahren sind im deutschen Bundesautobahnnetz verstärkt Schäden an vor 2005 errichteten Betonfahrbahndecken aufgetreten, die mit einer Alkali-Kieselsäure-Reaktion (AKR) in Verbindung gebracht werden. Neben dem AKR-fördernden Einfluss von alkalihaltigen Taumitteln werden Fahrbahndecken zyklischen mechanischen Belastungen infolge des Verkehrs und Zwangsspannungen durch klimatische Einwirkungen ausgesetzt. Solche mechanischen Belastungen werden bisher in keinem AKR-Prüfverfahren berücksichtigt. Die zyklischen Belastungen können zu einer Degradation des Betongefüges führen, die ggf. einen AKR-fördernden Einfluss hat. Dieser Beitrag stellt Untersuchungen vor, die zur Beantwortung der Frage nach dem Einfluss einer zyklischen mechanischen Belastung auf den AKR-Schadensprozess beitragen. Dabei wird der Hypothese nachgegangen, dass die ermüdungsinduzierte Degradation zu einer Erhöhung des Stofftransports führt. Dieser hat einen Einfluss auf die AKR-Schadensentwicklung, da die Reaktionspartner zunächst zum Reaktionsort transportiert werden müssen. Daher wird angenommen, dass sich mit dem Stofftransport auch die AKR-Schädigung verstärkt. Es werden Betonproben aus typischen Fahrbahndeckenbetonen einer vorgeschalteten zyklischen Druckschwellbelastung ausgesetzt. Die Degradation infolge der Vorbelastung wird simultan mittels ZfP-Verfahren charakterisiert. Anschließend werden die Auswirkungen der zyklischen Vorschädigung auf den Stofftransport sowie auf die AKR vergleichend an Prüfkörpern ohne und mit Vorschädigung untersucht. Die Ergebnisse lassen den Schluss zu, dass die zyklische Vorschädigung sowohl den Stofftransport als auch die AKR fördert. N2 - In recent years the German motorway network has seen an increase in the occurrence of damage to concrete road surfaces built before 2005, which can be attributed to the alkali-silica reaction (ASR). In addition to exposure to ASR-stimulating alkalirich deicing-agents, road surfaces are also subjected to cyclical mechanical loading resulting from traffic and induced stresses due to climatic impact. Such mechanical loadings are not considered in any of the previously developed ASR testing procedures. This cyclical loading could, however, lead to a degradation of the concrete microstructure and, in turn, stimulate the ASR-process. This article presents investigations that contribute to answering the question of whether a mechanically induced degradation influences the ASR-process. The hypothesis that the mechanically induced degradation leads to an increase in mass transport is examined. The mass transport is important for the ASR process because the reactants need to be transported to the reaction location before the reaction can take place. Therefore, it is assumed that increased mass Transport also leads to increased ASR damage. Concrete specimens made of typical pavement concretes are subjected to a predamaging cyclic compressive loading. The degradation is characterized simultaneously during the pre-damaging process using non-destructive testing (NDT) techniques. Then the effects of the cyclical pre-damage on the mass transport as well as on the ASR are determined by comparing results from test specimens with and without pre-damage. The results lead to the conclusion that the cyclical pre-damage increases both the mass transport and the ASR. KW - Stofftransport KW - Betonfahrbahndecken KW - AKR KW - Zyklische Belastung KW - Degradation PY - 2020 DO - https://doi.org/10.1002/best.202000017 SN - 0005-9900 VL - 115 IS - 10 SP - 779 EP - 788 PB - Wilhelm Ernst & Sohn CY - Berlin AN - OPUS4-51561 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Krütt, Enno A1 - Wallau, Wilma A1 - Meng, Birgit A1 - Greim, M. A1 - Pirskawetz, Stephan T1 - Automatisierte AKR-Prüfung im 60 °C-Betonversuch T1 - Automated ASR Concrete Prism Testing at 60 degrees C N2 - Der 60 °C-Betonversuch ist eine in Deutschland und international verbreitete Methode um die Empfindlichkeit von Gesteinskörnungen und Betonen hinsichtlich einer Alkali-Kieselsäure Reaktion (AKR) zu prüfen. Dieser Beitrag stellt eine neuentwickelte automatisierte Variante der Prüfmethode in einem Minireaktor vor. Dabei werden die Dehnungen von Betonprismen nicht, wie beim konventionellen Test manuell, sondern automatisch in entsprechend ausgerüsteten Prüfbehältern gemessen. Neben einer Reduzierung des Messaufwands bringt die automatisierte Prüfung im Minireaktor weitere Vorteile. Die Dehnungssignale werden, anders als bei der konventionellen Messung, quasi-kontinuierlich aufgezeichnet und bilden das Expansionsverhalten der Prismen detailliert ab. Außerdem bleiben Unterbrechungen der AKR-provozierenden Lagerung aus, die bei der konventionellen Prüfung notwendig sind. Im Beitrag werden die automatisierte und konventionelle Prüfung anhand der Dehnungen von Prismen zweier Gesteinskörnungen verglichen. In Übereinstimmung mit vorhergehenden Untersuchungen sind im Minireaktor gemessene Dehnungen systematisch kleiner als manuell gemessene. Als mögliche Ursache werden Unterschiede im Auslaugverhalten experimentell untersucht. Zur Überprüfung der Einstufung der zwei Gesteinskörnungen erfolgen außerdem Referenzprüfungen in der Nebelkammerlagerung bei 40 °C. N2 - The Concrete Prism Test at 60 °C (60 °C-CPT) is a common method to evaluate the susceptibility of concrete and aggregates to the Alkali-Silica Reaction (ASR). This paper presents a new device for an automated version of the 60 °C-CPT. The system monitors the expansion of concrete prism automatically. Compared to the conventional test method, effort and time consumption are notably reduced. The nearly continuous recording of expansion signals allows for studying of ASR-mechanisms in more detail than the conventional test. In addition, the interruptions of ASR-provoking storage, necessary for manual measurements, are avoided. The presented study compares results of conventional and automated testing of two types of aggregate. In accordance with previous findings, continuously stored prisms generally expand less than the conventionally tested prisms. To find a possible explanation, differences in leaching of alkali from the concrete prisms were quantified. For verifying the alkali-reactivity of the two aggregates, they were also classified in the fog chamber test at 40 °C, the German reference method. KW - Baustoffe KW - AKR KW - 60 °C-Betonversuch KW - Automatische Dehnungsmessung KW - Auslaugung KW - Building Materials KW - ASR KW - Concrete Prism Test at 60 °C KW - Automated expansion measurement KW - Leaching of alkalis PY - 2019 DO - https://doi.org/10.1002/best.201900040 SN - 1437-1006 SN - 0005-9900 VL - 114. Jahrgang IS - 12 SP - 911 EP - 918 PB - Ernst & Sohn AN - OPUS4-50062 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Fladt, Matthias T1 - Internal water-repellent treatment – a novel strategy for mitigating alkali-aggregate reaction in concrete pavements N2 - To prevent future alkali-aggregate reaction (AAR) damage, which has occurred frequently in the German highway network in recent years, a new regulation has been drafted. This regulation severely limits the use of alkali-sensitive aggregates by requiring that their suitability be verified by certified inspectors using newly developed AAR concrete tests that involve the external supply of alkali. This has led to a significant limitation in the number of aggregates usable for concrete pavements. A novel AAR avoidance strategy is now being pursued, which aims to enable the use of borderline alkali-sensitive aggregates through the application of an internal water-repellent treatment. The addition of water repellents during concrete production should significantly reduce the ingress of water and external de-icing salts into the concrete pavement, thus reducing the potential for AAR damage. This paper presents the results of laboratory tests to assess the suitability of this new AAR prevention strategy. Representative, highly AAR-susceptible road paving concrete made with an alkali-sensitive greywacke and various water repellents were used as the basis for these experiments. The tests for concrete suitability included determining the conventional fresh and hardened concrete properties as well as concrete prism tests with external alkaline supply. Building on these results, laser-induced breakdown spectroscopy (LIBS) analyses of de-icing-salt intrusion as well as microscopic examinations for verification of the AAR characteristics were carried out. The results of the AAR concrete tests with external alkaline supply support the conclusion that, when hydrophobic agents containing a suitable active ingredient are used, the AAR damage process in road paving concrete can be sufficiently prevented. T2 - 16th International Conference on Alkali-Aggregate Reaction in Concrete CY - Lisboa, Portugal DA - 31.05.2022 KW - Concrete pavements KW - Internal water-repellent treatment KW - Preventive measures KW - Testing for potential AAR PY - 2022 AN - OPUS4-56870 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - RPRT A1 - Weise, Frank A1 - Hüsken, Götz T1 - Ringversuch zum statischen Spaltzugversuch nach AL Sp-Beton N2 - Für die rechnerische Dimensionierung der Betondecken im Oberbau von Verkehrsflächen für den Neubau sowie die Erneuerung nach RDO-Beton 09 ist die statische Spaltzugfestigkeit an der unteren und oberen Bohrkernscheibe entsprechend der Vorgaben der AL Sp-Beton zu bestimmen. Aufgrund der unzureichenden Kenntnis der Präzision dieses Prüfverfahrens wurden, basierend auf dem Entwurf des FGSV-Merkblatts zur statistischen Auswertung von Prüfergebnissen, mit einem breit aufgestellten Ringversuch die statistischen Kennwerte an Labor- und Bestandsbetonen unter Vergleich- und Wiederholbedingungen ermittelt. Zur möglichst guten statistischen Absicherung nahmen an dem Ringversuch dreizehn erfahrene Prüfstellen teil, die vorab einem Audit unterzogen wurden. Zur Abdeckung des vielschichtigen Einsatzes des Prüfverfahrens erfolgte der Ringversuch an acht Prüflosen, die sowohl die Erst-/ Eignungsprüfung und Übereinstimmungskontrolle bei Neubaumaßnahmen, als auch die Restsubstanzbewertung von Betonfahrbahnplatten berücksichtigen. Zur Bewertung des Materialeinflusses wurde zusätzlich ein Prüflos mit Labormörtel untersucht. Die Probenvorbereitung erfolgte zentral an der BAM. Zur Sicherstellung einheitlicher Prüfbedingungen bei den Prüfstellen wurde zusätzlich eine detaillierte Standardarbeitsanweisung erarbeitet, die partiell bereits Eingang in das Normenwerk gefunden hat. Bei der Plausibilitätsprüfung aller prüflosspezifischen Einzelwerte der Spaltzug- und Druckfestigkeit wurden vereinzelt sowohl Ausführungsfehler als auch Übertragungs- und Tippfehler festgestellt. Der sich anschließende Lilliefors-Test zeigt, dass die ermittelten Einzelwerte bis auf wenige Aus-nahmen normalverteilt sind und damit die Voraussetzungen für die statistische Auswertung gegeben sind. Mittels grafischer Darstellung der Mandel’s h- und k-Werte wurden die Auffälligkeiten hinsichtlich der Mittelwerte und Varianzen prüflosspezifisch für die einzelnen Prüfstellen visualisiert und anschließend einige von ihnen mittels Grubbs- und Cochran-Test als Ausreißer identifiziert. Nach Ausreißerelimination wurde mit dem klassischen Verfahren bei der Spaltzugfestigkeit der geringste Variationskoeffizient unter Vergleich- und Wiederholbedingungen bei der Erst-/Eignungsprüfung mit 6,2 und 6,4 Prozent ermittelt. Bei einer Verminderung des Materialeinflusses durch die Verwendung eines Labormörtels verbessern sich die statistischen Kennwerte auf 4,5 und 5,3 Prozent. Mit 8,2 und 9,5 Prozent beziehungsweise 8,6 und 9,5 Prozent werden bei der Restsubstanzbewertung von Wasch- und Unterbetonen die höchsten Werte bestimmt. Das robuste Auswerteverfahren (ohne Eliminierung der Ausreißer) nach dem Entwurf des FGSV-Merkblatts zur statistischen Auswertung von Prüfergebnissen erwies sich in der Form als ungeeignet und bedurfte einer Überarbeitung. Bezüglich der vergleichend mit klassischen und robusten Verfahren gewonnenen Kennwerte ist festzustellen, dass bei sehr homogenen Messergebnissen eines Prüfloses beide Verfahren nahezu die gleichen statistischen Kennwerte liefern. Bei der Eliminierung von Ausreißern sind die Ergebnisse des robusten Verfahrens in der Regel etwas größer als die des klassischen Verfahrens. Die begleitenden vertiefenden Untersuchungen bei der Spaltzugprüfung mit innovativen Prüftechniken lieferten wertvolle Erkenntnisse zur Bewertung der Prüfeinflüsse. N2 - The computational design of concrete pavements according to the requirements of the RDO-Beton 09 requires the splitting tensile strength to be determined according to specifications of the AL Sp-Beton. However, detailed information on the precision of the described test procedure is missing. Therefore, a round robin test was set up in order to determine the statistical parameters of the prescribed splitting tensile strength test on laboratory concrete and cores extracted from concrete pavements in terms of repeatability and reproducibility. 13 testing institutes have been involved in the round robin test to guarantee a representative coverage of the sector. The selected testing institutes have been audited prior the round robin test in order to ensure their capabilities. The round robin test was divided into 8 testing lots for covering the broad field of possible applications. Thereby, the testing lots cover both the initial testing of concrete and quality control of new construction. The latter case implies also the assessment of existing concrete pavements. Additionally, a cementitious mortar was designed in order to consider the influence of the material, such as maximum grain size, on the test procedure. The samples were prepared at BAM to guarantee a uniform sample preparation. Furthermore, a standard operating procedure was prepared to assure constant test conditions at the testing institutes. This standard operating procedure is already partly considered by the corresponding standard. A revision of the data reported by the testing institutes revealed that execution errors, transcription errors as well as typing errors occurred. However, a Lilliefors-Test was conducted to verify the Gaussian distribution of the reported test data and to allow the further statistical analysis. Only view data sets do not follow a Gaussian distribution, has no remarkable influence on the obtained statistical data. By means of the graphical illustration of Mandel’s h- and k-values, abnormalities of the arithmetic mean and variance are depicted. These apparent abnormalities can be identified as outliers using the Grubbs and Cochran test. After eliminating the identified outliers, the corresponding statistical parameters have been determined using the classical method for data analysis. The lowest coefficient of variation that was determined for the splitting tensile strength by using the classical method for assessment of the repeatability and reproducibility of the test procedure amounts to 6.2 and 6.4%, respectively, for the initial testing of concrete. Reducing the material influence by using a cementitious mortar, the corresponding statistical parameters were reduced to 4.5 and 5.3%. On the contrary, the highest statistical values were obtained for the assessment of existing concrete pavements. Here, values of 8.2 and 9.5% were obtained for the exposed aggregate concrete and 8.6 and 9.5% for the subconcrete, respectively. The robust method for data analysis (without elimination of outliers) according to the draft version of the technical bulletin of the FGSV turned out to be inappropriate and required, therefore, a revision. Comparing the statistical parameters obtained by the classical and robust method used for data analysis it can be stated that both methods result in nearly identical values for homogeneous data sets without outliers. Considering outliers in the existing data sets, the statistical parameters obtained by the robust method are slightly higher than the values obtained by the classical method with elimination of outliers. The additional investigations on the splitting tensile strength using innovative test procedures provided valuable findings for the assessment of test results. KW - Verfahrenspräzision KW - Betonfahrbahndecke KW - Prüfverfahren AL Sp-Beton KW - Spaltzugfestigkeit KW - Ringversuch PY - 2022 SN - 978-3-95606-688-7 SN - 0943-9323 VL - Straßenbau Heft S 178 SP - 1 EP - 90 PB - Fachverlag NW in der Carl Ed. Schünemann KG CY - Bremen AN - OPUS4-54957 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kühnel, Alena T1 - 3D-Ansprache von Betonfahrbahndeckentexturen N2 - Die Oberflächentexturierung der Betonfahrbahndecken mittels Grinding und Grooving steht seit einigen Jahren im Mittelpunkt der Forschung und Entwicklung des Betonstraßenbaus in Deutschland. In den vergangenen Jahren wurden die vorteilhaften Oberflächenperformances derartiger Texturen, wie z.B. Griffigkeit, Ebenheit, Lärmminderung, in zahlreichen Forschungsprojekten umfassend untersucht. Im Kontext des gegenwärtig verfolgten ganzheitlichen performanceorientierten Ansatzes liegt der Fokus nun verstärkt auf der Analyse und Charakterisierung der Oberflächentopografie von Grinding- bzw. Groovingtexturen. Insbesondere gilt ein Hauptaugenmerk hierbei der zeitlichen Entwicklung der Oberflächentexturen in Abhängigkeit von äußeren Einwirkungen durch Klima und Verkehr. Im Rahmen eines von der Bundesanstalt für Straßenwesen (BASt) geförderten Forschungsvorhabens wurden zunächst die messtechnischen Voraussetzungen für eine hochaufgelöste dreidimensionale Erfassung der Oberflächentopografie von Grinding- und Groovingtexturen in situ geschaffen. Das schließt auch die Entwicklung einer Messanordnung, die eine Wiederholbarkeit der 3D-Messungen gewährleistet und somit die Erfassung der zeitlichen Texturveränderungen ermöglicht. Basierend darauf wurden Auswerteroutinen zur qualitativen und quantitativen Beschreibung der Oberflächentexturen und deren Veränderungen entwickelt und angewandt. Anschließend wurde der Zustand von Grinding- und Groovingtexturen an ausgewählten Praxisstrecken in definierten Zeitintervallen erfasst. Unter Verwendung der erarbeiteten Auswerteroutinen wurden die erfassten Oberflächen analysiert und repräsentative Texturkennwerte abgeleitet. T2 - Forschungskolloquium Betonstraßenbau CY - Dresden, Germany DA - 19.01.2023 KW - Betonfahbahndeckentexturen KW - Grinding KW - 3D-Laserscanning KW - Datenanalyse KW - Grooving PY - 2023 AN - OPUS4-56896 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Frei, Vivian A1 - Pirskawetz, Stephan A1 - Thiele, Marc A1 - Rogge, Andreas T1 - Ermüdungsverhalten von Beton für unterschiedliche Probekörpergeometrien N2 - Die zunehmende Anwendung hochfesten Betons in ermüdungsbelasteten Bauwerken, herausfordernde Belastungsszenarien im Bereich von On- und Offshore Windenergieanlagen bezüglich sehr hoher Lastwechselzahlen sowie das gleichzeitige Streben nach energie- und ressourcenschonendem Bauen stellen die Bemessung von Beton gegen Ermüdung vor neue Aufgaben. Eine Vielzahl von Studien beschreibt bereits die Auswirkung von Einflussfaktoren wie Mischungszusammensetzung, Feuchte, Probekörpergröße oder Belastungsart auf die Ermüdungsfestigkeit und den Ermüdungsprozess. Aufgrund der unterschiedlichen Geometrien und Mischungen der in den verschiedenen Studien verwendeten Proben sind die Auswirkungen der Einflussfaktoren jedoch kaum miteinander vergleichbar. In dem vom Bundesministerium für Wirtschaft und Klimaschutz (BMWK) geförderten Verbundprojekt WinConFat wurden deshalb verschiedene Einflussfaktoren gezielt an Proben mit einheitlichen Mischungen untersucht. Das durch die Bundesanstalt für Materialforschung und -prüfung (BAM) bearbeitete Teilprojekt fokussierte sich auf den „Einfluss der Probengeometrie und -größe auf die Ermüdung von Beton“. Neben der Erhebung von Daten zur Ermüdungsfestigkeit wurde der Ermüdungsprozess mit zerstörungsfreien Prüf- und Messmethoden untersucht. Diese Prüfmethoden wurden auch hinsichtlich ihrer Anwendbarkeit zur Erfassung der ermüdungsbedingten Schädigungsentwicklung an Betonbauwerken im Rahmen von Monitoringkonzepten bewertet. Untersucht wurden die Ermüdungsfestigkeiten und der Ermüdungsprozess an Zylindern mit drei unterschiedlichen Betonmischungen sowie unterschiedlicher Größe und Schlankheit. Die Ergebnisse dieser Untersuchungen werden im Folgenden vorgestellt und diskutiert. KW - Ermüdung KW - Hochfester Beton KW - Probengröße KW - Probengeometrie PY - 2024 VL - 644 SP - 1 EP - 135 PB - Beuth CY - Berlin AN - OPUS4-59647 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Erning, Johann Wilhelm T1 - Grabenkorrosion: Wie wissenschaftliche Diskussion eine Lösung ergibt. Und aktuelle Schäden durch Ignoranz N2 - In den 1990er Jahren traten ungewöhnliche Schäden an verzinkten Stahlrohren auf, für die ein Mechanismus zunächst nicht bekannt war. Die Diskussion führte zur Beschreibung des Mechanismus, der bereits in den 1970er Jahren beschrieben wurde. Nach etwa 20 Jahren treten die Schäden erneut auf, weil die Ursache erneut ignoriert wird. T2 - Sitzung GfKORR AK Schadensuntersuchung CY - Berlin, Germany DA - 09.04.2024 KW - Grabenkorrosion KW - C-Stahl PY - 2024 AN - OPUS4-61843 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Erning, Johann Wilhelm T1 - Brass under stress N2 - Different failure cases concerning brass alloys are discussed. The main connection is tensile stress due to processing in drinking water installations. The causes of the failures are discussed, solutions are given. T2 - Kormat 2024 CY - Zagreb, Croatia DA - 10.04.2024 KW - Brass KW - Corrosion KW - Drinking water PY - 2024 AN - OPUS4-61844 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Erning, Johann Wilhelm T1 - Korrosion an Rohren aus ferritischem Stahl 1.4521: Untersuchungen an Trinkwasserinstallationen mit Spaltkorrosion an Pressverbindungen N2 - Schäden durch Spaltkorrosion an Trinkwasserrohren aus 1.4521 werden diskutiert. Zur Ermittlung der Ursachen werden elektrochemische Versuche sowie das Korropad eingesetzt und Untersuchungen der Oberflächen gezeigt. T2 - Sitzung GfKORR AK Schadensuntersuchung CY - Berlin, Germany DA - 09.03.2024 KW - Spaltkorrosion KW - Trinkwasser KW - Nichtrostender Stahl PY - 2024 AN - OPUS4-61842 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Voigt, Marieke A1 - von Werder, Julia A1 - Meng, Birgit ED - Middendorf, B. ED - Fehling, E. T1 - Microstructure analysis of thermally treated ultra high performance concrete in the context of the durability performance N2 - Ultra high performance concrete (UHPC) is known for its high compressive strength of more than 150 MPa and its high durability. Thermal treatment at 90°C can accelerate the strength development so that the 28-days-strength can be achieved immediately after the treatment and an additional increase up to 30 % in some cases. The reason for the strength development is an accelerated hydration of the clinker minerals and an intensified pozzolanic reaction leading to a denser microstructure. In previous research inhomogeneities in form of a zonation after unprotected thermal treatment were observed and analysed in respect to changes in the microstructure. This zonation is defined by a different microstructure in the core compared to the outer zone in the matter of porosity, mineral phase composition and a significant change in the potassium and sulphur concentration of the zones is measurable. To isolate different transport mechanisms responsible for these element distributions UHPC samples were thermally treated at 90 °C and the microstructure was investigated under dry conditions and after immersion in water to investigate the influence of dehydration during and rehydration after the thermal treatment on the microstructure. Through durability testing via water absorption, water vapour diffusion, permeability testing and sulfuric acid resistance transport mechanisms like diffusion, migration, capillary suction are under investigation in correlation with the microstructure analysis. For the microstructure analysis measurements with µXRF, mercury intrusion porosity, XRD and SEM were conducted. T2 - HiPerMat 2020 CY - Kassel, Germany DA - 11.03.2020 KW - UHPC KW - Thermal treatment KW - Zonation KW - Transport mechanism KW - Durability PY - 2020 SN - 978-3-7376-0828-2 DO - https://doi.org/10.17170/kobra-202002271026 VL - 23 SP - 151 EP - 152 PB - Kassel University Press CY - Kassel AN - OPUS4-52373 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Tan, Yi A1 - Wachtendorf, Volker A1 - Klack, Patrick A1 - Kukofka, Tobias A1 - Ruder, J. A1 - Schartel, Bernhard T1 - Durability of the flame retardance of ethylene-vinyl acetate copolymer cables: Comparing different flame retardants exposed to different weathering conditions N2 - Scientific publications addressing the durability of the flame retardance of cables during their long-term application are rare and our understanding lacks. Three commercial flame retardants, aluminum hydroxide, aluminum diethyl phosphinate (AlPi-Et), and intumescent flame retardant based on ammonium polyphosphate, applied in ethylene-vinyl acetate copolymer (EVA) model cables, are investigated. Different artificial aging scenarios were applied: accelerated weathering (UV-irradiation/temperature/rain phases), humidity exposure (elevated temperature/humidity), and salt spray exposure. The deterioration of cables’ surface and flame retardancy were monitored through imaging, color measurements, attenuated total reflectance Fourier transform infrared spectroscopy, and cone calorimeter investigations. Significant degradation of the materials’ surface occurred. The flame retardant EVA cables are most sensitive to humidity exposure; the cable with AlPi-Et is the most sensitive to the artificial aging scenarios. Nevertheless, substantial flame retardance persisted after being subjected for 2000 h, which indicates that the equivalent influence of natural exposure is limited for several years, but less so for long-term use. KW - Durability KW - Flame retardant KW - Cable KW - Weathering KW - Cone calorimeter PY - 2020 DO - https://doi.org/10.1002/APP.47548 SN - 0021-8995 VL - 137 IS - 1 SP - 47548 PB - Wiley AN - OPUS4-50237 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Voigt, Marieke A1 - von Werder, Julia A1 - Meng, Birgit T1 - Investigation of the zonation of thermally treated ultra high performance concrete N2 - Ultra high performance concrete (UHPC) is characterised by its high compressive strength of more than 120 MPa and its high durability. With thermal treatment at 90°C, hydration is accelerated and a strength comparable to the 28-day strength can be achieved immediately after the treatment. In applying Optimum process conditions, the strength can be even further increased by up to 30%. Previous Research showed that thermal treatment can lead to inhomogeneities in form of a visible zonation within the cross-section, if the UHPC is not protected sufficiently from desiccation. This led to the question, to what extent the related changes in mechanical properties, microstructure and phase composition are of relevance for the performance of the UHPC. First investigations of small specimens thermally treated without protection exhibited a decrease of compressive strength, indicating that the zonation aspect requires further research. In this study the zonation of UHPC treated thermally at 90°C is investigated after applying four different procedures of treatment and curing in comparison. The samples are characterized with respect to their chemistry, mineral composition and microstructure to allow an assessment on durability and strength development, with focus on potential depth dependent changes associated with the zonation. The measurements reveal the formation of a visible zonation in case of unprotected treatment, if followed by immersion in water. The compressive strength is not significantly impaired, but a decrease in bending strength gives reason for concern. Further results allow clear correlation with changes in pore structure, whereas the interpretation of relationships with phase distribution, degree of hydration, microchemistry is more complex and therefore, provides only partial clarification. KW - UHPC KW - Thermal treatment KW - Zonation KW - Desiccation KW - Microstructure KW - Durability PY - 2020 DO - https://doi.org/10.1016/j.conbuildmat.2020.119187 VL - 254 SP - 119187 PB - Elsevier Ltd. AN - OPUS4-50828 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ziemann, M. A. T1 - Insight into Concrete Deterioration with Raman Spectroscopy N2 - Alkali-silica reaction (ASR) is a serious Problem concerning the deterioration of concrete. This leads to significant maintenance and reconstruction costs for concrete infrastructures all over the world. The geographical regions, which play a major role in concrete deterioration, are for example coastal Areas or in general, areas with a high air humidity/salinity due to closeness of rivers or lakes. These exemplary results show, the application of Raman spectroscopy establishes a valuable approach for characterizing the chemical and structural composition of ASR-products. The results prove the potential to trace the kind of reaction products, developing in dependence on the aggregate and to follow up its local alteration from origin of the gel. T2 - 10th International Congress on the Application of Raman Spectroscopy in Art and Archaeology (RAA2019) CY - Potsdam, Germany DA - 03.09.2019 KW - Building Materials KW - Alkali-silica-reaction KW - ASR KW - Raman Spectroscopy PY - 2019 AN - OPUS4-49471 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bäßler, Ralph A1 - Aristia, Gabriela T1 - Geothermie aus dem Vulkan – sicher und wirtschaftlich N2 - Indonesien gilt aufgrund seiner vielen Vulkane als einer der Hotspots für Geothermie. Doch Salz und Hitze setzen den Geothermie‐Anlagen zu und gefährden ihre Sicherheit und Wirtschaftlichkeit. Ein Team an der BAM hat günstigen, lokal verfügbaren Baustahl jetzt so beschichtet, dass ein nachhaltiger und sicherer Betrieb der Geothermie‐Kraftwerke möglich ist ‐ auch unter Extrembedingungen. Das BAM‐Team will das Beschichtungssystem nun den Anwendern in Indonesien zur Verfügung stellen, damit es unter Realbedingungen in einem Geothermie‐Kraftwerk getestet werden kann. Der Schutz vor Korrosion ist mitentscheidend, weil sie die Lebensdauer dieser Kraftwerke bestimmt. Unsere Arbeit könnte die Effizienz der Energieproduktion mit Geothermie wesentlich verbessern. KW - Geothermie KW - Korrosion PY - 2020 DO - https://doi.org/10.1002/maco.202070086 SN - 1521-4176 SN - 0947-5117 VL - 71 IS - 8 SP - 1 EP - 2 PB - WILEY‐VCH Verlag GmbH & Co. KGaA CY - Weinheim AN - OPUS4-51074 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Bäßler, Ralph T1 - Review: Corrosion‐Resistant Linings and Coatings N2 - This book introduces to aspects to be considered when dealing with coatings and linings. Philip A. Schweitzer covers and compares a variety of specific coatings and their applications. In 18 chapters he divided the content into two main parts: linings and coatings. All professionals involved in design and maintenance processes get by this book a compact survey of necessary considerations which needs to be done when applying surface protection measures. The literature references at the end of some chapters support the readers finding additional information about the special topic, mainly written by the author himself. Since this newly issued paperback edition is a 1:1 re‐print of the 2001 hardcover version, neither current publications are referenced, nor revisions were made. KW - Corrosion KW - Lining KW - Coating KW - Elastomer PY - 2020 DO - https://doi.org/10.1002/maco.202070094 SN - 1521-4176 SN - 0947-5117 VL - 71 IS - 9 SP - 1592 EP - 1593 PB - WILEY‐VCH Verlag GmbH & Co. KGaA CY - Weinheim AN - OPUS4-51167 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Bäßler, Ralph T1 - Review: Corrosion Atlas Case Studies - 2019 Edition N2 - This edition, published as first issue within the series “Corrosion Atlas”, provides 181 corrosion case studies, collected from 29 contributors. These Corrosion Atlas Case Studies provide a helpful tool required for engineers in their daily life to quickly determine and solve their equipment's corrosion problems by compact theoretical background and vivid examples. It fulfills the intension of the editors to be “the first centralized collection of case studies containing challenges paired directly with solutions together in one location”. KW - Corrosion KW - Failure KW - Water-bearing PY - 2020 DO - https://doi.org/10.1002/maco.202070054 SN - 1521-4176 SN - 0947-5117 VL - 71 IS - 5 SP - 859 PB - WILEY‐VCH Verlag GmbH & Co. KGaA CY - Weinheim AN - OPUS4-50757 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - RPRT A1 - Beltran, R. A1 - Frei, Vivian A1 - Marx, S. T1 - Ultraschallprüfungen zur Erfassung der Schädigungsentwicklung unter verschiedenen Umweltbedingungen und unter zyklischer Druckschwellbelastung N2 - Derzeit ist die Instandhaltung von großen Betontragwerken wie Brücken oder Windenergieanlagen problemorientiert und von einem reaktiven Vorgehen geprägt. Das bedeutet, erst wenn sichtbare Schäden vorliegen, werden diese meist unter Beeinträchtigung des Betriebs instand gesetzt. Im Hinblick auf die Entwicklung von prädiktiven Instandhaltungsstrategien, deren Fokus in der langfristigen Bauwerksüberwachung und der Vorhersage von Schädigungsentwicklungen liegt, wurde die Anwendung von Ultraschallverfahren für die Identifizierung der Degradationsprozesse von Betontragwerken unter Ermüdungsbeanspruchung untersucht. Hierzu fanden Arbeiten im vom Bundesministerium für Wirtschaft und Klimaschutz (BMWK) geförderten Verbundprojekt WinConFat zum "Einfluss der Probengeometrie und -größe auf die Ermüdung von Beton" an der Bundesanstalt für Materialforschung und -prüfung (BAM) und zu den "Methoden zur Zustandsanalyse von Windenergieanlagen" am Institut für Massivbau (IfMa) der Leibniz Universität Hannover (LUH) statt, welches zudem vom Deutschen Beton- und Bautechnik Verein e.V. (Forschungsvorhaben DBV-311) gefördert wurde. Dabei wurden verschiedene Einflussfaktoren auf die Schädigungsentwicklung unter Ermüdungsbeanspruchung wie die Probekörpergröße, das Belastungsniveau und die Betonfestigkeit untersucht. Als Schädigungsindikator und Vergleichsparameter wurden die Ultraschallgeschwindigkeit und der dynamische E-Modul des Betons verwendet. Um das Potential der Schädigungserfassung im Beton mittels Ultraschallprüfung umfassender zu bewerten, wurden zusätzlich Versuche an Betonproben unter monoton steigender Belastung, Kriechversuche, Temperaturversuche und Untersuchungen an großformatigen Balken durchgeführt. KW - Ultraschallprüfung KW - Ermüdung KW - Hochfester Beton PY - 2024 SN - 978-3-410-65917-4 SN - 0171-7197 VL - 651 SP - 1 EP - 102 PB - Beuth CY - Berlin AN - OPUS4-59801 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CHAP A1 - Schartel, Bernhard ED - Hu, Y. ED - Wang, X. T1 - Influence of the Size and Dispersion State of Two-Dimensional Nanomaterials on the Fire Safety of Polymers N2 - Only the nano-scaled structure of the nanocomposite and the dispersion of nanoparticles within the polymer matrix harbor multifunctional potential including superior fire retardancy. Thus, this chapter focuses on the dispersion of nanoplates, based mainly on studies of layered silicates and graphene/graphene-related nanoplates. The nanostructure and properties of the nanocomposites are dependent mainly on thermodynamic and kinetic factors during preparation. Improving nano-dispersion often directly improves flame retardancy. Therefore, the modification of the nanoplates as well as the preparation of nanocomposites becomes very important to control this dispersion. The dispersion of nanoplates functions as a prerequisite for the formation of an efficient protective layer, changing the melt flow and dripping behavior, or the improvement of the char properties. KW - Nanocomposite KW - Flame retardancy KW - 2D nanoparticle KW - Exfoliation KW - Dispersion KW - Flammability PY - 2023 SN - 978-1-032-35268-8 SN - 978-1-032-35502-3 SN - 978-1-003-32715-8 DO - https://doi.org/10.1201/9781003327158-2 SP - 23 EP - 58 PB - CRC Press CY - Boca Raton AN - OPUS4-58290 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - RPRT A1 - Bettge, Dirk A1 - Bäßler, Ralph A1 - Le, Quynh Hoa A1 - Kranzmann, Axel T1 - Abschlussbericht des Projektteils CLUSTER - BAM: Werkstoffauswahl und Festlegung von Obergrenzen für Verunreinigungen in variierenden CO2-Strömen auf Grund von realitätsnahen Korrosionsexperimenten - FKZ 03ET7031C - im Projektverbund CLUSTER: Auswirkungen der Begleitstoffe in den abgeschiedenen CO2‐Strömen unterschiedlicher Emittenten eines regionalen Clusters auf Transport, Injektion und Speicherung N2 - Nachdem im Verbundprojekt COORAL das Hauptaugenmerk auf überkritisches CO2 gelegt wurde, d. h. Transport über kurze Strecken bei erhöhter Temperatur, wurde in CLUSTER ein größeres lokales Transport-Netzwerk betrachtet, bei dem CO2 bei geringeren Temperaturen, also vorwiegend im flüssigen Zustand transportiert wird. Wurden in COORAL die CO2-Ströme von Kohlekraftwerken untersucht, ging es in CLUSTER zusätzlich um die Emissionen von relevanten Industrien, deren CO2-Emissionen nicht ohne Weiteres vermieden werden können. Aufgrund der Erfahrungen in COORAL konnte eine Auswahl von kommerziellen Werkstoffen getroffen werden, die für einen konkreten Einsatz für CCS zur Verfügung stünden. Die gemischten und fluktuierenden CO2-Zusammensetzungen sind bei geeigneten Begrenzungen der Begleit¬stoffe im CO2 bezüglich Korrosionsvorgänge beherrschbar. Die Machbarkeit eines lokalen CCS-Clusters erscheint daher gegeben, soweit dies die Anlagen für Kompression, Transport und Injektion betrifft. KW - CCS KW - Korrosion KW - CO2-Speicherung KW - Pipelines PY - 2019 SP - 1 EP - 67 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-50249 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - RPRT A1 - Reinemann, Steffi A1 - Lehmann, Jens A1 - Rosemann, Paul A1 - Babutzka, Martin A1 - Bohlmann, Tatjana A1 - Burkert, Andreas T1 - Optimierung industrieller Korundschleifprozesse zur Sicherstellung der Korrosionsbeständigkeit nichtrostender Stähle N2 - Durch eine breite Beteiligung von Schleifmittelherstellern, -anwendern und wissenschaftlichen Einrichtungen im projektbegleitenden Ausschuss (PA) konnte der vielschichtige Themenkomplex „Schleifen“ im Kontext zu den Projektzielen umfassend untersucht werden. Es wurden praxisrelevante Parameterfelder definiert, die eine erfolgreiche Aufklärung der Projektfragestellung ermöglichten. Im Zuge der Untersuchungen wurde ein signifikanter Einfluss beim Einsatz von Granulatschleifbändern auf das Korrosionsverhalten geschliffener Oberflächen festgestellt. Damit zeigten geschliffene Oberflächen regelmäßig eine schlechtere Korrosionsbeständigkeit als Oberflächen, die mit sonst gleichen Parametern mit einlagig gestreuten Bändern bearbeitet wurden. Die durch einige Untersuchungsergebnisse aus vorangegangenen AiF-Vorhaben ursprünglich verfolgte These, dass Unterschiede in der Korrosionsbeständigkeit auf die Kornart der Schleifmittel Korund bzw. SiC zurückzuführen ist, konnte nur bedingt bestätigt werden. Bei den systematischen Untersuchungen innerhalb dieses Projektes erwies sich der Einfluss der Kornart im Vergleich zum Einfluss des Schleifbandtyps (Granulat bzw. einlagig gestreutes Korn) als weniger relevant. Durch weiterführende Untersuchungen konnten auf Oberflächen, die mit Granulatschleifbändern bearbeitet wurden, große Materialaufplattungen aus Eigenmaterial festgestellt werden. Das Eigenmaterial wird dabei im Schleifprozess zunächst abgetragen und aufgrund der Topografie des Schleifbandes zeitweise auf den Bändern festgehalten. Später lösen sich diese Materialanhäufungen vom Band ab und können prozessbedingt durch Wärme- und Krafteinwirkung auf den bearbeiteten Oberflächen aufgeplattet werden. Durch REM und KorroPad Untersuchungen ließen sich Bereiche mit solchen Eigenmaterialaufplattungen eindeutig als wesentliche Ausgangspunkte für Korrosionsprozesse identifizieren. Das aufgeplattete Material ist stark verformt, thermisch beeinflusst und bildet eine Spaltgeometrie zur Bauteiloberfläche aus. Diese Veränderungen führen zur Störung der Passivschichtausbildung in diesen Bereichen und verursachen damit eine erhöhte Korrosionsanfälligkeit der Oberflächen. Durch gezielte Nachbearbeitungsprozesse ist es möglich, die Eigenmaterialaufplattungen von den Oberflächen zu entfernen. Im Rahmen des Vorhabens wurde dazu eine Nachbearbeitung mittels Schleifvlies geprüft, die zu einer Entfernung der Eigenmaterialaufplattungen und damit zu einer Wiederherstellung der erwarteten Korrosionsbeständigkeit führte. Wird der Endschliff von Oberflächen mit einlagig gestreutem Korn ausgeführt, sind ebenfalls keine korrosionsrelevanten Materialaufplattungen zu erwarten. Die in einem vorhergehenden AiF Vorhaben IGF 17136 N/1 entwickelte Methode der KorroPad-Prüfung konnte auch hier erfolgreich für die Untersuchung der Auswirkung unterschiedlicher Prozessparameter auf die Korrosionsbeständigkeit der Oberflächen eingesetzt werden. Zudem erwies sich das EPR-SL-Verfahren als ein weiterer Ansatz, um die Passivschichtstabilität verschieden geschliffener Oberflächen vergleichend untersuchen zu können. Mit den nun vorliegenden Erkenntnissen können kmU künftig durch Anpassungen und Optimierung von Schleifprozessen eine gute Korrosionsbeständigkeit der bearbeiteten Oberflächen sicherstellen. Die Optimierung der Prozessparameter und -schritte kann durch den Einsatz der KorroPad-Prüfung Inhouse erfolgen und somit die laufende Fertigung im Rahmen der Qualitätsprüfung überwacht und dokumentiert werden. KW - KorroPad KW - Korrosion KW - Korrosionsbeständigkeit KW - Korrosionsschutz KW - Verfleckungen KW - Nichtrostender Stahl KW - Schleifen KW - Oberfläche PY - 2019 SP - 1 EP - 74 AN - OPUS4-47729 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - RPRT A1 - Babutzka, Martin A1 - Valet, Svenja A1 - Kotula, Stefan A1 - Burkert, Andreas A1 - Gümmer, K. A1 - Bender, S. A1 - Huckshold, M. T1 - Normentwurf für ein Prüfverfahren zur Bestimmung von Deckschichtwiderständen an Zinküberzügen mittels gelartiger Elektrolyte N2 - Das Grundproblem der heute verfügbaren und normativ geregelten Prüfverfahren für Zinküberzüge besteht neben den realitätsfernen Prüfbedingungen vor allem in der subjektiv geprägten Auswertung der Prüfergebnisse. Die systematische Betrachtung der Entwicklungen der letzten Jahre zeigt, dass die üblichen Verfahren den aktuellen Anforderungen damit schon vom Ansatz her nicht gerecht werden können und auch die bisher betriebene, fortlaufende Variation und Anpassung von Prüfbedingungen keinen grundlegend neuen Lösungsansatz bieten können. Ein solcher ergibt sich nur, wenn die Zinküberzüge hinsichtlich der kinetischen Eigenschaften der Deckschichtbildung und -auflösung umfassend beschrieben werden können, was nur durch den Einsatz elektrochemischer Untersuchungsmethoden mittels Gelelektrolyten möglich ist. Aus diesem Grund wurde im Verbundforschungsvorhaben GELELEK auf der Basis elektrochemischer Methoden unter Verwendung eines Gelelektrolyten ein Normenvorschlag für eine Prüfnorm erarbeitet und zur Normungsreife geführt, welcher den Anforderungen an ein Messsystem für Feldanwendungen entspricht. Im Verbundforschungsvorhaben GELELEK wurde eine gezielte Kombination von Laboruntersuchungen mit Untersuchungen im Feld und Bauteilen unter realen Einsatzbedingungen angestrebt. Randbedingungen für eine gesicherte Messung von atmosphärisch bewitterten Zinküberzügen unter Einsatz von Gelelektrolyten wurden erarbeitet und im Normenvorschlag festgeschrieben. Darüber hinaus wurde ein mobiles Messgerät für Messungen mit Gelelektrolyten an realen Bauteilen entwickelt. Nach Abschluss des Forschungsvorhabens steht Industrievertretern und Prüfinstituten ein wissenschaftlich gesichertes Messverfahren basierend auf Kennwerten zur Verfügung, um Zinküberzüge und deren momentane Schutzwirkung unter praxisrelevanten Bedingungen einschätzen und normativ geregelt prüfen zu können. Der vorliegende Forschungsbericht gibt einen Überblick über die Motivation zur Durchführung des Forschungsvorhabens, wichtige Arbeitsschritte, Details zur entwickelten Prüfmethode sowie Einsatzmöglichkeiten für Prüfinstitute und Unternehmen. KW - Normung KW - Zink KW - Korrosion KW - Deckschichtbildung KW - Atmosphärische Korrosion KW - Korrosionsprüfung PY - 2022 UR - https://www.gav-verzinken.de/forschung/wissenspool SP - 1 EP - 24 AN - OPUS4-54947 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Schilling, Markus A1 - Marschall, Niklas A1 - Niebergall, Ute A1 - Böhning, Martin T1 - Dataset of comprehensive Full-notch creep tests (FNCT) of selected high-density polyethylene (PE-HD) materials N2 - The dataset provided in this repository comprises data obtained from a series of full-notch creep tests (FNCT) performed on selected high-density polyethylene (PE-HD) materials (for further details, see section 1 Materials in this document) in accordance with the corresponding standard ISO 16770. The FNCT is one of the mechanical testing procedures used to characterize polymer materials with respect to their environmental stress cracking (ESC) behavior. It is widely applied for PE-HD materials, that are predominantly used for pipe and container applications. It is based on the determination of the time to failure for a test specimen under constant mechanical load in a well-defined and temperature controlled liquid environment. The test device used here also allows for continuous monitoring of applied force, specimen elongation and temperature. KW - Polyethylene KW - Environmental Stress Cracking KW - Full-notch creep test KW - PE-HD KW - Crack growth PY - 2023 DO - https://doi.org/10.5281/zenodo.10143351 PB - Zenodo CY - Geneva AN - OPUS4-58835 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Su, C. A1 - Shi, J. A1 - Durlo Tambara, Luis Urbano A1 - Yang, Y. A1 - Liu, B. A1 - Revilla-Cuesta, V. T1 - Improving the mechanical properties and durability of steam-cured concrete by incorporating recycled clay bricks aggregates from C&D waste N2 - The output of C&D waste is increasing year by year, among which low-quality recycled brick aggregates (RBAs) have not been well utilized and brought environmental burden. The durability of steam-cured concrete (HCC) is often compromised due to the detrimental effects of this curing regime on the long-term performance and microstructure development of the concrete material. To address this issue, this study investigates the potential of incorporating RBAs to improve the long-term durability of HCC. The results demonstrate that the incorporation of a small amount of RBA (10–20%) not only enhances the 28-d strength of HCC by 2.5–11.3%, but also improves its impermeability by mitigating heat damage effects. The combined application of fine and coarse RBA was found to effectively balance the negative effects of coarse RBA on the performance of HCC. Furthermore, the utilization of RBA in HCC was shown to have economic and environmental benefits. The results of this study demonstrate a simple and effective approach to improve the long-term durability of HCC while promoting the high-value utilization of solid waste. KW - Steam-cured concrete KW - C&D waste KW - Durability KW - Recycled aggregate KW - Environmental benefits PY - 2024 DO - https://doi.org/10.1016/j.powtec.2024.119571 VL - 438 SP - 1 EP - 14 PB - Elsevier B.V. AN - OPUS4-59799 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Frenck, Johanna-Maria A1 - Frenck, Georg A1 - Degener, Sebastian A1 - Vollmer, Malte A1 - Niendorf, Thomas T1 - Interrelationships of stress-induced martensitic phase transformation and pitting corrosion in iron-based shape memory alloys N2 - Orientation dependence of stress-induced martensitic transformation under compression and the influence of a corrosion attack on superelastic properties were investigated for Fe42.7Mn34.7Al13.4Ni7.7Cr1.5 (at.−%) single crystals. The results of incremental strain tests show that the crystallographic orientation has a considerable impact on the superelastic performance, eventually resulting from the formation of twinned or detwinned martensite to accommodate strain as well martensite variant interaction. In order to investigate the effect of a corrosive environment on the mechanical performance and martensitic transformation, compression specimens were immersed in a 5.0 wt.−% NaCl solution for 24 h before tested in incremental strain tests. The immersion of the compression specimens revealed a partial surface corrosion attack including localized pitting corrosion. The localized corrosion attack increased the number of active martensite plates, most probably due to an induced multiaxial stress state. Further investigations on specimens subjected to −6% compressive strain revealed that areas with retransformed martensite serve as nucleation zones for corrosion damage. Stress-induced corrosion cracks developed, which eventually deteriorate functional response. KW - Shape memory alloy (SMA) KW - In situ characterization KW - Corrosion KW - Austenite-to-martensite phase transformation PY - 2024 DO - https://doi.org/10.1016/j.mtla.2023.102001 VL - 33 SP - 1 EP - 11 PB - Elsevier BV AN - OPUS4-61283 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Geburtig, Anja T1 - Significance of new data pairs for irradiance and (surface) temperature N2 - There is consent that UV irradiance and temperature at the place of photodegradation are the most important environmental parameters in weathering, along with humidity. This contribution shows how an improvement in the measurement data situation can improve the significance and comparability of outdoor exposures. Photooxidative ageing is calculated using sample polymers for which the corresponding modelling data (Exposure Response Functions, ERF) is available. The mean square deviations are estimated, which result from using different spectral irradiances and different spectral sensitivities, both of the sensors and the polymers. It will be shown here how the significance of the irradiance values increases with increasing approximation of the spectral sensitivities of the sensor and polymer. Also, the mean square deviations are estimated, which result from using different activation energies and surface temperatures. A selection of different variables to describe the weathering exposure is created. The potential of either individual values or data pairs is evaluated in terms of significance or correlation to the calculated photooxidative ageing. Recording hourly data also enables subsequent evaluations of individual test specimens, adapted to the respective colour or to determine activation energies. An accumulated value, calculated from PIT-radiometer irradiance and a suited surface temperature, can provide a comparison of different outdoor exposures over different locations or years. Thus, a characterisation of the weathering exposure would be related to a reference spectral sensitivity (much closer to a polymer than that of a common UV radiometer), one reference activation energy, and different surface temperature scenarios with, on the one hand, graded solar absorptions (white / grey / black) and, on the other hand, different thermal couplings (coated metal / thick plastic). This results in three values each for plastic samples and coated metals (light / grey / dark). It will never be possible to accurately predict the weathering tests for individual samples (with their specific sensitivities), but the proposed approaches can go a long way towards the comparability of outdoor weathering exposures. T2 - 10th European Weathering Symposium EWS CY - Graz, Austria DA - 11.09.2024 KW - Polymer 3R KW - Outdoor weathering PY - 2024 AN - OPUS4-61292 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Simon, Patrick T1 - Bayesian system identification of a reinforced concrete beam subject to temperature variations based on static response data N2 - Changes in the measured response of structural systems can be an indication of structural damages. However, such changes can also be caused by the effect of varying environmental conditions. To detect, localize and quantify changes or damages in structural systems subject to varying environmental conditions, physics-based models of the structural systems have to be applied which explicitly account for the influence of ambient conditions on the structural behavior. Data obtained from the structural systems should be used to calibrate the models and update predictions. Bayesian system identification is an effective framework for this task. In this paper, we apply this framework to learn the parameters of two competing structural models of a reinforced concrete beam subject to varying temperatures based on static response data. The models describe the behavior of the beam in the uncracked and cracked condition. The data is collected in a series of load tests in a climate chamber. Bayesian model class selection is then applied to infer the most plausible condition of the beam conditional on the available data. T2 - Tenth International Conference on Bridge Maintenance, Safety and Management (IABMAS 2020) CY - Online meeting DA - 11.04.2021 KW - Bayesian system identification KW - Reinforced concrete KW - Damage identification KW - Environmental effects KW - Structural health monitoring KW - Structural systems PY - 2021 AN - OPUS4-52812 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Unger, Jörg F. T1 - Data provenance - from experimental data to trustworthy simulation models and standards N2 - Data provenance - from experimental data to trust worthy simulation models and standards Jörg F. Unger, Annika Robens-Radermacher, Erik Tamsen Bundesanstalt für Materialforschung und -prüfung (BAM). Unter den Eichen 87, 12205 Berlin, Germany FAIR (findable, accessible, interoperable and reusable) data usage is one of the main principals that many of the research and funding organizations include in their strategic plans, which means that following the main principals of FAIR data is required in many research projects. The definition of data being FAIR is very general, and when implementing that for a specific application or project or even setting a standardized procedure within a working group, a company or a research community, many challenges arise. In this contribution, an overview about our experience with different methods, tools and procedures is outlined. We begin with a motivation on potential use cases for the applications of FAIR data with increasing complexity starting from a reproducible research paper over collaborative projects with multiple participants such as Round-Robin tests up to data-based models within standardization codes, applications in machine learning or parameter estimation of physics-based simulation models. In a second part, different options for structuring the data are discussed. On the one hand, this includes a discussion on how to define actual data structures and in particular metadata schema, and on the other hand, two different systems for storing the data are discussed. The first one is the open BIS system, which is an opensource Lab notebook and Postgre SQL based data management system. A second option are a semantic representations using RDF based ontologies for the domain of interest. In a third section, requirements for workflow tools to automate data processing are discussed and their integration into reproducible data analysis is presented with an outlook on required information to be stored as metadata in the database. T2 - 4th International Congress on Materials & Structural Stability CY - Rabat, Morocco DA - 08.03.2023 KW - Data provenance KW - Experimental data to trustworthy KW - Simulation models and Standards PY - 2023 AN - OPUS4-57333 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Spilker, A. A1 - Stelzner, Ludwig T1 - Analyse der thermischen Dehnung von Fahrbahndeckenbetonen aus dem BAB-Netz N2 - Die Kenntnis von Materialeigenschaften spielt bei der Entwicklung oder Optimierung von Betonen und Bauweisen für den Straßenbau sowie der Qualitätskontrolle und -sicherung eine bedeutende Rolle. Gleichermaßen bilden physikalische Materialkennwerte die Grundlage für die rechnerische Dimensionierung und die Restsubstanzbewertung von Betonfahrbahndecken. Einen relevanten Kennwert bei der Untersuchung thermisch induzierter Spannungsund Verformungszustände stellt der thermische Ausdehnungskoeffizient von Beton dar. Dieser beeinflusst beispielsweise maßgeblich das Längsdehnungsverhalten des Deckensystems sowie das Ausmaß von Plattenkrümmungen und Fugenbewegungen. Im Zuge der systematischen Weiterentwicklung der rechnerischen Dimensionierung aber auch im Zusammenhang mit der gezielten Verbesserung der Gebrauchseigenschaften von Fahrbahndecken gilt es zu hinterfragen, ob lastunabhängige Formänderungseigenschaften, wie z. B. der thermische Ausdehnungskoeffizient der verwendeten Betone, aktuell ausreichend Beachtung finden, ob allgemeine Literaturwerte für die heutigen Fahrbandeckenbetone stets Gültigkeit besitzen und ob deren Implementierung in moderne Rechenmodelle zu validen Ergebnissen führt. Für eine empirische Herangehensweise ist die Verfügbarkeit adäquater Prüfverfahren von entscheidender Bedeutung. In Deutschland existiert aktuell jedoch kein standardisiertes oder genormtes Verfahren für die prüftechnische Bestimmung des thermischen Ausdehnungskoeffizienten von Beton. Daher wurden unter Beachtung straßenbauspezifischer Gesichtspunkte zwei Prüfansätze entwickelt, die in diesem Beitrag vorgestellt und hinsichtlich möglicher Messunsicherheiten und Messungenauigkeiten diskutiert werden. Außerdem erfolgt die Darstellung ausgewählter Ergebnisse aus Analysen an Bestandsbetonen aus dem BAB-Netz. Im Ergebnis sollen die Untersuchungen einen Beitrag zur Schaffung der prüftechnischen Voraussetzungen für eine abgesicherte Quantifzierung der thermischen Dehnung von Fahrbahndeckenbetonen leisten. T2 - Betonstraßentagung 2019 CY - Aschaffenburg, Germany DA - 26.09.2019 KW - Thermische Dehnung KW - Fahrbahndeckenbetone KW - Baustoffe PY - 2019 SN - 978-3-86446-260-3 SP - 1 EP - 13 AN - OPUS4-49485 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Thiele, Marc T1 - Fatigue in Concrete N2 - The current knowledge about fatigue behavior of concrete is still incomplete. This concerns especially the progress of fatigue which precedes the fatigue failure. An overview on the fatigue behaviour in concrete is given. Therefore, the process of fatigue itself under cyclic compressive loading was investigated in a systematic and comprehensive way. The aim of this investigation was to obtain a deeper insight and to provide a better understanding of the damage process occurring within the material during fatigue loading. T2 - 1st Infrastar Training School CY - IFSTTAR, Nantes, France DA - 08.04.2019 KW - Fatigue KW - Concrete PY - 2019 AN - OPUS4-48945 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Robens-Radermacher, Annika T1 - Efficient reliability analysis by combining uncertain measurement data, Bayesian model updating and reduced order modeling N2 - The efficiency of structural model updating and the subsequent reliability analysis is increased by using the advantages of reduced order models. Coupling a reduced model of the structure of interest with a Bayesian model updating approach or an reliability analysis to estimate the failure probability reduce the computational cost of such complex analyses drastically. T2 - 8th Workshop on High-Dimensional Approximation (HDA) 2019 CY - Zurich, Switzerland DA - 09.09.2019 KW - Reduced order modeling KW - Bayesian model updating PY - 2019 AN - OPUS4-49035 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Baeßler, Matthias A1 - Bhuyan, Delwar A1 - Hille, Falk A1 - Viefhues, Eva A1 - Döhler, M. A1 - Mevel, L. ED - Zingoni, Alphose T1 - Impact of environmental based effects on SHM strategies N2 - Environmental based perturbations influence significantly the ability to identify structural dam-age in Structural Health Monitoring. Strategies are needed to classify such effects and consider them appropri-ately in SHM. It has to be considered if seasonal effects just mask the structural response or if temperature itself correlates to a weakening of the structure. Various methods have been developed and analyzed to separate environmental based effects from damage induced changes in the measures. Generally, two main approaches have emerged from research activity in this fields: (a) statistics-based tools analyzing patterns in the data or in computed parameters and (b) methods, utilizing the structural model of the bridge considering environmental as well as damage-based changes of stiffness values. With the background of increasing affordability of sensing and computing technology, effort should be made to increase sensitivity, reliability and robustness of proce-dures, separating environmental from damage caused changes in SHM measures. The contribution describes an attempt to evaluate both general strategies, their advantages and drawbacks. In addition, two vibration moni-toring procedures are introduced, allowing for temperature-based perturbations of the monitoring data. T2 - SEMC 2019 CY - Cape Town, South Africa DA - 02.09.2019 KW - SHM environmental bridges PY - 2019 SN - 978-1-138-38696-9 SN - 978-0-429-42650-6 DO - https://doi.org/10.1201/9780429426506 SP - Paper 324, 1 EP - Paper 324, 6 PB - CRC Press CY - Boca Raton AN - OPUS4-49167 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Breitenbücher, R. A1 - Przondziono, R. A1 - Meng, Birgit A1 - Krütt, Enno A1 - Weise, Frank T1 - Alkali-Kieselsäure-Reaktion in Betonfahrbahndecken unter Berücksichtigung von Verkehr und Taumitteln N2 - In Betonfahrbahndecken treten häufig Schäden auf, welche mit einer Alkali-Kieselsäure-Reaktion (AKR) in Verbindung gebracht werden. Obwohl die Hintergründe einer solchen AKR intensiv untersucht wurden, gibt es bei Betonfahrbahndecken besondere Randbedingungen, welche die Schadreaktion signifikant erhöhen können. Diese sind vor allem die Überlagerung der mikrostrukturellen Degradation durch Verkehrsbeanspruchung mit externer Alkali-Zufuhr durch Taumittel. Bisherige Untersuchungen der AKR beschränkten sich auf die Ausgangsstoffe (Gesteinskörnung, Zement, Bewertung des Betons), wobei die besonderen Randbedingungen außer Acht gelassen wurden. Betonfahrbahndecken sind zyklischen Belastungen aus Verkehr und Witterungsbedingungen ausgesetzt. In einem gemeinschaftlichen Forschungsprojekt wurden die verschiedenen, gegenseitig voneinander abhängigen, Einflussfaktoren auf eine schädigende AKR in Betonfahrbahndecken sowohl experimentell untersucht als auch numerisch modelliert. Auf Mikro-Ebene wurden die AKR-bezogenen Transportprozesse innerhalb der Gesteinskörnung, sowie die Gelbildung und der Ionen-Transport, untersucht. Auf Meso-Ebene fokussierte das Projekt auf die Charakterisierung der durch zyklische Belastung induzierten Schädigung im Mikrogefüge des Betons. Des Weiteren wurde das Transportverhalten in ein derart geschädigtes Betongefüge mit und ohne Berücksichtigung des zusätzlichen Einflusses überrollender Reifen beschrieben und dessen Auswirkung auf eine AKR analysiert. Schließlich wurde auf Makro-Ebene das Risiko eines AKR-bedingten Schadens bewertet. Einige ausgewählte Ergebnisse werden in diesem Beitrag dargestellt. KW - AKR KW - Zyklischen Belastung KW - Degradation KW - Flüssigkeitstransport KW - Verkehr PY - 2019 VL - 8 SP - 1 EP - 15 PB - Kirschbaum Verlag GmbH CY - Bonn AN - OPUS4-49153 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Baeßler, Matthias T1 - Impact of environmental based effects on SHM strategies N2 - Anwendungen der Bauwerksüberwachung werden häufig stark von jahreszeitlichen Einflüssen wie Temperaturbeanspruchungen beeinflusst. Der Beitrag diskutiert Probleme und Lösungen zum Umgang mit diesen Einflüssen. T2 - SEMC 2019 CY - Cape Town, South Africa DA - 02.09.2019 KW - SHM Environmental PY - 2019 AN - OPUS4-49163 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Herrmann, Ralf T1 - Introduction and Current Research in Wind Energy N2 - The EERA Wind is a Joint Program for coordination of research in wind energy. In the subprogram SP7 "Structures, materials and components" BAM introduces its current research topics in the field of on- and offshore wind energy and structural health monitoring. T2 - EERA Joint Program Wind: SP7 WORKSHOP on Structures, Materials and Components CY - Amsterdam, Niederlande DA - 24.09.2019 KW - Offshore KW - Wind energy KW - EERA Joint Program PY - 2019 AN - OPUS4-49203 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Simon, Patrick T1 - Structural Health Monitoring (SHM) unter Temperatureinflüssen N2 - Beim Structural Health Monitoring (SMH) besteht eine der Hauptsächlichen Störgrößen im Einfluss der Umgebungsbedingungen, insbesondere der Temperatur. Es wird ein Einblick in die Problemstellung gegeben sowie Lösungsansätze diskutiert und aktuelle Forschung an der BAM vorgestellt. T2 - Internes Arbeitskolloquium TU Berlin CY - Berlin, Germany DA - 11.10.2019 KW - Structural Health Monitoring KW - Structural Health Monitoring KW - Temperatureinflüsse KW - Temperature effects KW - SHM KW - SHM PY - 2019 AN - OPUS4-49265 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Herrmann, Ralf T1 - Vibration Analysis of Structures using a Drone (UAV) based Mobile Sensing Platform N2 - The identification of the dynamic behavior of structures, like bridges and towers, is relevant to address multiple issues. In many cases the dynamic parameters should be acquired only once or at a frequency that doesn’t justify the installation of distinct vibration sensors for a long-term monitoring. To identify modal frequencies of a structure, a drone based mobile sensing platform has been implemented. This sensing platform measures the relative displacement be-tween the structure and the drone, which also shows a strong dynamic behavior under wind tur-bulences. By regarding the dynamic model of the drone and additional measurements at the dis-tance sensor the absolute movement of the structure can be estimated based on the measured relative distance. This time domain data is a suitable input for various operational modal analysis algorithms. The system has been used to identify the dynamic properties of test and real structure, like a 1.5 MW wind turbine tower. T2 - 5th International Conference on Smart Monitoring, Assessment and Rehabilitation of Civil Structures (SMAR 2019) CY - Potsdam, Germany DA - 27.08.2019 KW - Modal Analysis KW - Drone KW - Vibration KW - Wind Turbines KW - Bridges PY - 2019 AN - OPUS4-49205 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Voigt, Marieke A1 - von Werder, Julia A1 - Meng, Birgit ED - Caprai, V. ED - Brouwers, H. J. H. T1 - Investigation of the zonation of thermally treated ultra high performance concrete N2 - Ultra high performance concrete (UHPC) is characterised by its high compressive strength of more than 150 MPa and its high durability. Due to thermal treatment at 90°C a strength comparable to the 28-days-strength can be achieved immediately after the treatment and in some cases can be even further increased up to 30 %. The explanations for the increase in strength are the accelerated hydration of the clinker minerals and the intensified pozzolanic reaction contributing to a denser microstructure and hence, a high performance in compressive strength. Former research shows that thermal treatment can lead to inhomogeneities in form of a visible zonation within the cross-section. The width of the margin increases with shorter pre-storage time before the thermal treatment and with omitting protective measures against desiccation during the treatment. Specimens exhibiting a zonation typically show a lower compressive strength compared to the undisturbed reference whereas changes in chemistry, mineral content and microstructure were not reported in detail. In this study the zonation of thermally treated UHPC is investigated with respect to its chemistry, mineral composition and microstructure to allow predictions on durability and strength development. Measurements show a change in pore sizes, minerals phase composition and element distribution leading to the visible zonation and weaker bending tensile strength compared to the reference. T2 - 2nd International Conference of Sustainable Building Materials CY - Eindhoven, Netherlands DA - 12.08.2019 KW - UHPC KW - Thermal treatment KW - Zonation KW - Desiccation KW - Microstructure KW - Durability PY - 2019 VL - 2 SP - 185 EP - 193 AN - OPUS4-49479 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Nerger, Deborah A1 - Hille, Falk A1 - Moosavi, Robabeh A1 - Grunwald, Marcel A1 - Redmer, Bernhard A1 - Kühn, T. A1 - Hering, M. A1 - Bracklow, F. T1 - Improved tomographic investigation for impact damage characterization N2 - Reinforced concrete (RC) is used as structural material in most diverse civil engineering applications. For the variability of its physical properties it is still an engineering challenge to meet all necessary requirements for the prediction of dynamic effects under impact loading. In this paper, investigations are shown within the scope of quantifying and evaluating the damage caused by an impact. The experimental investigations are performed in the field of low- and medium-velocity impact. The chosen flat nose shape results in small penetrations on the top side and scabbing on the bottom side. The plate is scanned with an adapted planar tomographic examination after the impact, and the damage is analysed, afterwards. Cracks and spalling are made visible with a reconstruction. The numerical model validated on the tomographic results justifies the application for further predictions of the damage description. T2 - 25th International Conference on Structural Mechanics in Reactor Technology - SMIRT25 CY - Charlotte, NC, USA DA - 04.08.2019 KW - Impact KW - Damage characterization KW - Planar tomography KW - Numeric simulation KW - Reinforced concrete structure PY - 2019 SP - Paper Div 5 S8, 1 EP - 9 AN - OPUS4-49541 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Nerger, Deborah T1 - Post-impact evaluation at RC plates with planar tomography and FEM N2 - Due to the many possible applications, the uncomplicated production and the high application range, reinforced concrete is a widely used building material. This large range of physical material properties still poses an engineering challenge in determining all necessary requirements for predicting dynamic effects under impact load. Many aspects of impact have already been examined and some correlations have been studied intensively. Examples are the work of Lastunen and Booker, who studied the influence of projectile properties on the impact form. Li has also investigated the local effects of an impact. The field of detailed damage analysis has not been in focus so far. This presentation shows some studies in medium-velocity impact with the focus on post-impact damage evaluation. The impactor is modified so that the test plates show low penetration on the top and scabbing on the bottom. With the unique tomography lab test stand at BAM the plate is scanned after the impact and the damage is analyzed. Cracks and scabbing are made visible with a reconstruction. The comparison of simulation and tomography allows to create prognosis models for damage characterization. T2 - 36th Danubia Adria Symposium on Advances in Experimental Mechanics CY - Pilsen, Czech Republic DA - 24.09.2019 KW - Impact KW - Damage characterization KW - Planar tomography KW - Numeric simulation KW - Reinforced concrete structure PY - 2019 AN - OPUS4-49691 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Seher, Julia T1 - Ein hydrothermaler Verwertungsweg für Mauerwerkbruch N2 - Jährlich fallen ca. 250 Mio. t mineralische Reststoffe in Deutschland an, die eine vielfältig einsetzbare, sekundäre Rohstoffquelle darstellen. Der Einsatz von Reststoffen führt zur Schonung natürlicher Rohstoffe, zur Reduktion von CO2-Emissionen und zur Einsparung von Deponieraum. Der Reststoff Mauerwerkbruch ist ein heterogenes, SiO2-reiches Gemisch aus Ziegeln, Beton und Leichtbeton, Kalksandstein, Porenbeton, Putz und Mörtel. Die uneinheitliche Zusammensetzung und bis zu 50 % Feinanteile nach der mechanischen Aufbereitung verhindern eine unmittelbare Wiederverwertung als RC-Gemisch. Eine Möglichkeit der Verwertung von Mauerwerkbruch stellt das rohstoffliche Recycling über einen hydrothermalen Stoffumwandlungsprozess dar, bei dem poröse Granulate erhalten werden. Im Fokus des ZIM-Projekts HYTEGRA steht die Entwicklung eines solchen Herstellungsprozesses und die umfassende Charakterisierung der hergestellten Hydrothermalgranulate. Als Reststoffe soll neben Mauerwerkbruch (SiO2-reich) aus Bau- und Abbruchsabfällen auch Papierasche (CaO-reich) aus dem Altpapierrecycling eingesetzt werden. Nach einem mehrstufigen mechanischen Prozess erfolgt die Härtung der Grüngranulate hydrothermal unter erhöhtem Druck in gesättigter Wasserdampfatmosphäre bei Temperaturen von etwa 200 °C. Während des Härtungsprozesses bilden sich aus Quarz (SiO2), Kalk (CaO) und Wasser Calciumsilicathydrat-Phasen, die für die benötige Festigkeit und Porosität der Hydrothermalgranulate sorgen. Durch die Variation verschiedenster Syntheseparameter (Temperatur, Druck, Zeit, SiO2-CaO-Mischungsverhältnis) wird eine gezielte Einstellung der Eigenschaften der Hydrothermalgranulate ermöglicht. In Kooperation mit verschiedenen Industriepartnern sind Anwendungen als Filter- und Speichermaterial geplant, z.B. in Bodenfiltern zur Abwasserbehandlung sowie als temporärer Wasserspeicher zur inneren Nachbehandlung von Beton und in Pflanzsubstraten. Im Vortrag sollen das Projekt HYTEGRA und erste Ergebnisse des hydrothermalen Verwertungsweg unter Verwendung von Mauerwerkbruch im Labormaßstab vorgestellt werden. T2 - Abteilungs-Vortragsseminar Abteilung 7 Bauwerkssicherheit CY - Berlin, Germany DA - 07.11.2019 KW - Rohstoffliches Recycling KW - Mauerwerkbruch KW - Poröse Granulate PY - 2019 AN - OPUS4-49535 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Seher, Julia T1 - Hydrothermale Herstellung von Filter- und Speichermaterialien aus SiO2- und CaO-reichen Reststoffen N2 - Jährlich fallen ca. 250 Mio. t mineralische Reststoffe in Deutschland an, die eine vielfältig einsetzbare, sekundäre Rohstoffquelle darstellen. Der Einsatz von Reststoffen führt zur Schonung natürlicher Rohstoffe, zur Reduktion von CO2 Emissionen und zur Einsparung von Deponieraum. Im Projekt HYTEGRA sollen Mauerwerkbruch (SiO2-reich), ein heterogenes Gemisch aus Ziegeln, Beton und Leichtbeton, Kalksandstein, Porenbeton, Putz und Mörtel, sowie Papierasche (CaO-reich) aus dem Altpapierrecycling rohstofflich wiederverwertet werden. Die Entwicklung von porösen Körnungen über einen hydrothermalen Herstellungsprozess steht dabei im Fokus. In Kooperation mit verschiedenen Industriepartnern sind Anwendungen als Filter- und Speichermaterial geplant. T2 - Tagung Bauchemie CY - Aachen, Germany DA - 30.09.2019 KW - Poröse Granulate KW - Rohstoffliches Recycling KW - Mauerwerkbruch PY - 2019 AN - OPUS4-49374 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Voigt, Marieke T1 - Investigation of the zonation of thermally treated ultra high performance concrete N2 - Ultra high performance concrete (UHPC) is characterised by its high compressive strength of more than 150 MPa and its high durability. Due to thermal treatment at 90°C a strength comparable to the 28-days-strength can be achieved immediately after the treatment and in some cases can be even further increased up to 30 %. The explanations for the increase in strength are the accelerated hydration of the clinker minerals and the intensified pozzolanic reaction contributing to a denser microstructure and hence, a high performance in compressive strength. Former research shows that thermal treatment can lead to inhomogeneities in form of a visible zonation within the cross-section. The width of the margin increases with shorter pre-storage time before the thermal treatment and with omitting protective measures against desiccation during the treatment. Specimens exhibiting a zonation typically show a lower compressive strength compared to the undisturbed reference whereas changes in chemistry, mineral content and microstructure were not reported in detail. In this study the zonation of thermally treated UHPC is investigated with respect to its chemistry, mineral composition and microstructure to allow predictions on durability and strength development. Measurements show a change in pore sizes, minerals phase composition and element distribution leading to the visible zonation and weaker bending tensile strength compared to the reference. T2 - 2nd International Conference of Sustainable Building Materials CY - Einhoven, Netherlands DA - 11.08.2019 KW - UHPC KW - Thermal treatment KW - Zonation KW - Desiccation KW - Microstructure KW - Durability PY - 2019 AN - OPUS4-49472 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Weise, Frank T1 - AKR an Betonfahrbahndecken - ausgewählte Einflussgrößen und neuartige AKR-Vermeidungsstrategie N2 - In den letzten Jahren sind im deutschen Bundesautobahnnetz vermehrt Schäden an vor 2005 hergestellten Betonfahrbahndecken aufgetreten, die mit einer Alkali-Kieselsäure-Reaktion (AKR) in Verbindung gebracht werden. Vor diesem Hintergrund werden in diesem Beitrag zunächst die Voraussetzungen und ausgewählte Einflussgrößen für eine schädigende AKR aufgezeigt. Besondere Aufmerksamkeit wird dabei der Rolle des Tausalzeintrags durch den Winterdienst bei Betonfahrbahndecken geschenkt. So wird mit Löseversuchen in 1 M KOH-Lösung zweier Gesteinskörnungen bei 80 °C gezeigt, dass mit zunehmender NaCI-Zugabe die Löslichkeit von SiÖ2 zunimmt und die von AI2O3 eine Verminderung erfährt. Basierend auf dem so exemplarisch erbrachten Nachweis für die Verstärkung der schädigenden AKR durch das Tausalz wird die Notwendigkeit und Richtigkeit der Durchführung von AKR-Betonversuchen mit Alkalizufuhr im ARS 04/2013 zur zukünftigen Vermeidung von AKR-Schäden an Betonfahrbahndecken im Rahmen von Neubau- und Erneuerungsmaßnahmen im Bundesfernstraßennetz belegt. Zusätzlich durchgeführte WS-Grundprüfungen nach dem ARS 04/2013 mit den beiden Gesteinskörnungen der Löse versuche veranschaulichen, dass die nach der Alkali- Richtlinie des DAfStb als unbedenklich eingestuften Gesteinskörnungen bei den Betonversuchen mit Alkalizufuhr durchaus als alkaliempfindlich bewertet werden können. Dies wiederum führt zu einer Verminderung der für den Betonstraßenbau verfügbaren Gesteinskörnungen. Vor diesem Hintergrund wird nach neuartigen AKR-Vermeidungsstrategien gesucht, die auch eine Verwendung der als grenzwertig alkaliempfindlich eingestuften Gesteinskörnungen erlaubt. Einen möglichen Lösungsansatz stellt in diesem Kontext die Innenhydrophobierung des Fahrbahndeckenbetons dar. Es soll so durch die Behinderung des Feuchte- und Tausalzeintrags in den Beton der AKR-Schädigungsprozess signifikant vermindert werden. Für die Bewertung der Leistungsfähigkeit der Innenhydrophobierung zur Vermeidung bzw. Verminderung einer schädigenden AKR in Betonfahrbahndecken wird zurzeit im Aufträge der BASt an der BAM ein Forschungsvorhaben bearbeitet. Im Rahmen dieses Beitrags werden erste Ergebnisse dieses Projekts vorgestellt. So wird exemplarisch an einem Oberbeton (D > 8)/Unterbeton und einem Oberbeton 0/8 mit einer alkaliempfindlichen Gesteinskörnung der Einfluss zweier Hydrophobierungsmittel auf die Frisch- und Festbetoneigenschaften ganzheitlich aufgezeigt und bewertet. Bei Letzteren stehen zunächst die mechanischen und hygrischen Parameter sowie der Frost-Tausalzwiderstand im Vordergrund. In einem weiteren Schritt wird der Einfluss beider Hydrophobierungsmittel auf die schädigende AKR mittels AKR-Betonversuchen mit Alkalizufuhr beleuchtet. Dabei gelangen ergänzend zur Beurteilung des Tausalzeintrags die Laser-Induced Breakdown Spectroscopy (LIBS) und zur Bewertung der Ausprägung der AKR und sekundären Ettringitbildung (SEB) die Dünnschliffmikroskopie zum Einsatz. T2 - 9. Betonfachtagung 2019 CY - Berlin, Germany DA - 12.11.2019 KW - AKR KW - Betonfahrbahn KW - Innenhydrophobierung KW - Tausalzeintrag KW - AKR-Betonversuche PY - 2019 SN - 978-3-7640-0633-4 SP - 159 EP - 176 AN - OPUS4-50056 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Unger, Jörg F. T1 - Efficient reliability analysis with model reduction techniques N2 - One of the most important goals in civil engineering is to guaranty the safety of constructions. National standards prescribe a required failure probability in the order of 10-6 (e.g. DIN EN 199:2010-12). The estimation of these failure probabilities is the key point of structural reliability analysis. Generally, it is not possible to compute the failure probability analytically. Therefore, simulation-based methods as well as methods based on surrogate modelling or response surface methods have been developed. Nevertheless, these methods still require a few thousand evaluations of the structure, usually with finite element (FE) simulations, making reliability analysis computationally expensive for relevant applications. The aim of this contribution is to increase the efficiency of structural reliability analysis by using the advantages of model reduction techniques. Model reduction is a popular concept to decrease the computational effort of complex numerical simulations while maintaining a reasonable accuracy. Coupling a reduced model with an efficient variance reducing sampling algorithm significantly reduces the computational cost of the reliability analysis without a relevant loss of accuracy. T2 - MathMet2019 CY - Lisbon, Portugal DA - 20.11.2019 KW - Reliability method KW - Numerical example PY - 2019 AN - OPUS4-49989 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Eberwein, Robert A1 - Rogge, Andreas A1 - Behrendt, F. A1 - Knaust, Christian T1 - Dispersion Modeling of LNG-Vapor on Land – A CFD-Model Evaluation Study N2 - Based on methane from renewable resources, LNG is an alternative fuel for heavy and long-distance traffic in land transport. Contrary to its positive properties, the fuel contains risks from an explosion and extremely low temperatures for personal and infrastructure safety. CFD-models are suitable for doing risk analyses for arbitrary scenarios. For examining how to model for risk research the dispersion of LNG-vapor, this paper contains a model variant study, with an evaluation by experiments. This paper describes the use of the CFD-code ANSYS Fluent for simulating experiments of the ‘LNG Safety Program Phase II‘. The content of the well-documented experiments was the research of the vaporization rate of LNG on land and the dispersion of LNG-vapor in the air. Based on the comparison to two experiments, overall 12 CFD-model variants with varying thermal and turbulence parameters were examined how they affect the transient LNG-vapor dispersion in air. The definition of turbulence-boundary-condition at the domain borders had the biggest impact on modeling, followed by the turbulence model. The most accurate model variant had been applied for observing the spreading behavior of LNG-vapor in the air after evaporation on land and analyzing the influence of the LNG-composition to the dispersion. The results show that the mixture of LNG-vapor and the air in the free field is cooler than the ambient air and spreads like a heavy gas on the ground. KW - LNG KW - CFD KW - Heavy gas KW - Model evaluation PY - 2020 DO - https://doi.org/10.1016/j.jlp.2020.104116 VL - 65 SP - 104116 PB - Elsevier Ltd. AN - OPUS4-50697 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Baeßler, Matthias T1 - Recap: Main Results of the BUMP Study and Relevance for VERBATIM N2 - Zusammenfassung des Forschungsprojekts BUMP hinsichtlich der Relevanz für das Projekt VERBATIM N2 - BUMP had been a theoretical prestudy on open issues for the pile tip buckling of large monopiles. The presentation summarizes the main results and considers the impact for the ongoing VERBATIM project. VERBATIM is set up as a mainly experimental verification project for pile buckling. T2 - Kick-Off Projekt VERBATIM CY - BAM, Berlin, Germany DA - 23.01.2020 KW - Buckling piles circular shells PY - 2020 AN - OPUS4-50515 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Wachtendorf, Volker A1 - Wägner, Yannick A1 - Geburtig, Anja T1 - Gedanken, Tipps & Tricks zu künstlichen Bewitterungsprüfungen N2 - Die Fragestellung kann nur exemplarisch dargestellt werden, aber ist hoffentlich auch für langjährige Praktiker in den ausgewählten Punkten interessant. Es sollen für folgende Bereiche Beispiele gegeben werden: Probenvorbereitung, Testvorbereitung, Testdurchführung und Auswertung. T2 - 53. Jahrestagung der GUS 2025 CY - Stutensee-Blankenloch bei Karlsruhe, Germany DA - 26.03.2025 KW - Wechseltemperaturen KW - Künstliche Bewitterung KW - Prüfung KW - UV KW - Feuchte KW - Beregnung PY - 2025 SN - 978-3-9826129-2-8 VL - 53 SP - 253 EP - 257 PB - Gesellschaft für Umweltsimulation e.V. CY - 76327 Pfinztal (Berghausen) AN - OPUS4-62861 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kühnel, Alena A1 - Stelzner, Ludwig A1 - Weise, Frank T1 - Measurement and analysis of concrete pavement surface textures using hand-held 3D laser scanning technology N2 - Concrete pavement surface textures are divided by means of their dimension into four categories: microtexture, macrotexture, megatexture and roughness. They influence the most important performance characteristics of road surfaces, such as friction (also referred to as “skid resistance”), tire/pavement noise, evenness and surface drainage. These properties are relevant for driving safety, comfort and environmental aspects. Up to now, research in Germany has focused on monitoring these characteristics by tire/pavement noise and skid resistance measurements. However, the topography of surface textures has not been sufficiently investigated and evaluated until now. The development and availability of high-performance, hand-held 3D scanning systems during the last years enable measurements of the microtexture and macrotexture of concrete pavement surfaces at short measuring times and high resolution. This paper shows the ability of modern laser-based technology to record three-dimensional data of different concrete pavement surface textures in situ. For this purpose, a special measuring frame has been developed. The presented results were primarily obtained within the framework of a research project commissioned by the German Federal Highway Research Institute (BASt) and processed by the Federal Institute for Materials Research and Testing. Various concrete pavement surface textures by means of diamond grinding and hybrid of diamond grinding and grooving were investigated in situ. In addition, exposed aggregate concretes (EAC), which were introduced as a standard type of concrete for motorway pavements in Germany in 2006, have been analyzed. Based on the gathered 3D data, evaluation routines for qualitative and quantitative analysis have been developed and applied. The aim was to derive the statistical parameters such as the relative and cumulative frequency distribution of the profile depth as well as the roughness coefficient for diamond ground pavements and EAC. Also, the “mean profile depth” (MPD) as a common texture-related parameter was determined. T2 - 14th International Symposium on Concrete Roads CY - Krakow, Poland DA - 25.06.2023 KW - Concrete pavement surface textures KW - 3D Laser Scanning KW - Diamond Grinding KW - Exposed aggregate concrete KW - Data analysis KW - Surface characteristics PY - 2023 SP - 1 EP - 14 AN - OPUS4-57893 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - von Werder, Julia A1 - Simon, Sebastian A1 - Meng, Birgit T1 - Internal sulfate resistance of concrete N2 - If the amount of sulfate within the mix design for concrete is not balanced, ettringite formation which first controls solidification continues while the concrete is hardening. Ettringite forms by reaction of sulfate contained in the cement or in some admixture with calcium aluminate (C3A) as cement component. The “late primary ettringite formation” promotes an increase in volume within the hardened concrete leading to cracks. To analyze the effect of substituting part of ordinary Portland cement (OPC) by a treated brown coal fly ash mortar bars were tested according to ASTM C452. This test method was originally developed to extrapolate from the internal to external sulfate attack and is based on the idea that by testing a concrete mixture containing sulfate the process of deterioration is accelerated because it does not have to diffuse into the concrete before reaction first. In addition to the samples prescribed in ASTM C452 further samples in the size of the German SVA procedure were tested also designed for accessing the external sulfate resistance. The results show that while the replacement of 25 % of cement by brown coal fly ash leads to length changes around the limit defined by ASTM, the substitution of 50 % cement exceeded the limit by a multiple. The progress of expansion is the very similar for the two geometries tested. In-situ XRD measurements confirmed that while for pastes made of OPC the formation of ettringite is completed after 20 hours, this is not true for the mixtures containing the brown coal fly ash. In a different study the effect of hydrothermal treatment on the phase composition of ultra-high-performance concrete was analyzed. The results show that the sulfate and aluminate resulting from the decomposition of ettringite are bound into new phases. If this binding is permanent this might allow the larger use of sulfate bearing raw materials. T2 - EuroCoalAsh 2021 Conference CY - Online meeting DA - 02.11.2021 KW - Brown coal fly ash KW - Ettringite KW - Internal sulfate resistance KW - Test methods KW - In-situ XRD KW - Hydrothermal treatment PY - 2021 SP - 131 EP - 137 CY - Thessaloniki AN - OPUS4-54133 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Burkert, Andreas A1 - Lehmann, Jens T1 - Merkblatt 833 - Edelstahl Rostfrei in Erdböden N2 - Für Anwender nichtrostender Stähle wird im neu überarbeiteten Merkbaltt 833 eine Planungshilfe für Anwendungen nichtrostender Stähle in Erdböden gegeben. Hinweise und Empfehlungen zur Werkstoffauswahl sowie allgemeine Hinweise zum Einsatz nichtrostender Stähle und auch Anwendungsbeispiele sind im neu überarbeitetn Merkblatt enthalten. KW - Nichtrostender Stahl KW - Korrosion KW - Erdboden PY - 2019 UR - https://www.edelstahl-rostfrei.de/publikationen/iser-publikationen/merkblatt-833-edelstahl-rostfrei-in-erdboeden IS - 2. überarbeitete Auflage SP - 1 EP - 13 PB - Informationsstelle Edelstahl Rostfrei CY - Düsseldorf AN - OPUS4-49710 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Bäßler, Ralph T1 - Review: Advanced Coating Materials N2 - This book by Scrivener Publishing contains 14 chapters written by 82 leading scientists, experienced in the field of coatings. They demonstrate mechanisms, usage and manipulation of cutting‐edge coating methods. Each chapter is well structured and ends with a conclusion, highlighting the content. The book is divided into 3 parts: “Materials and Methods”, “Coating Materials Nanotechnology” and “Advanced Coating Technology and Applications”. Finally, this book provides a comprehensive insight into innovative research in advanced coating materials and state‐of‐the‐art technologies, without being a real textbook. It fulfills its intension of being beneficial both for technicians and scientists. KW - Corrosion KW - Coating KW - Protection PY - 2020 DO - https://doi.org/10.1002/maco.202070044 SN - 1521-4176 SN - 0947-5117 VL - 71 IS - 4 SP - 675 EP - 676 PB - WILEY‐VCH Verlag GmbH & Co. KGaA CY - Weinheim AN - OPUS4-50629 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Herrmann, Ralf A1 - Hille, Falk A1 - Said, Samir A1 - Sterthaus, Jens A1 - Müller, Karsten A1 - Quercetti, Thomas A1 - Wille, Frank A1 - Paffenholz, J.-A. A1 - Baeßler, Matthias ED - Papadrakakis, M. ED - Fragiadakis, M. ED - Papadimitriou, C. T1 - Implementing a Structural Health Monitoring system using digital models of the BAM large drop test facility in Horstwalde N2 - At the Bundesanstalt für Materialforschung und -prüfung (BAM) full scale specimens for nuclear transport and storage containers (casks) are tested for their structural integrity in a series of drop tests on the Test Site Technical Safety in Horstwalde, 50 km south of Berlin. These drop tests cause a major stress not only on the casks, but also on the steel tower structure of the test facility, itself. The load pattern makes the structure very interesting for detailed investigation. The focus of the monitoring lies on the bolted joints of the flange connections that are a typical connection for cylindrical elements if welding is technical or economical unfavorable. The definition of the monitoring takes was done by investigating the existing documents and inspection results accompanied by building an initial digital representation of the structure, consisting of two finite element (FE) models and a geometrical 3D point cloud representation. As a first step the structures behavior during static and dynamic loading was analyzed using measurement data and an updated numerical FE Model. The idea behind is to use models for a digital planning and operation/evaluation of the structural health monitoring. A static FE simulation and a dynamic FE simulation are generated, to investigate how the structure behaves under the load conditions. T2 - XI International Conference on Structural Dynamics (EuroDyn 2020) CY - Online meeting DA - 23.11.2020 KW - Structural Health Monitoring KW - Drop Tests KW - System Identification KW - Digital Models KW - BIM PY - 2020 UR - https://generalconferencefiles.s3-eu-west-1.amazonaws.com/eurodyn_2020_ebook_procedings_vol1.pdf SN - 978-618-85072-0-3 VL - 1 SP - 1293 EP - 1304 PB - Institute of Structural Analysis and Antiseismic Research CY - Athen AN - OPUS4-51592 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Herrmann, Ralf T1 - Digitale Methoden und Werkzeuge im BIM Kontext N2 - Die BAM Tagung "Messen im Bauwesen" widmete sich beim 10 Auftakt den digitalen Methoden und Werkzeugen im Bauwesen. T2 - Messen im Bauwesen 2018 CY - Berlin, Germany DA - 13.11.2018 KW - Messen im Bauwesen KW - BIM KW - Tagung PY - 2019 UR - https://onlinelibrary.wiley.com/doi/epdf/10.1002/bate.201970105 DO - https://doi.org/10.1002/bate.201970105 SN - 1437-0999 VL - 96 IS - 1 SP - 78 EP - 78 PB - Ernst & Sohn Verlag für Architektur und technische Wissenschaften GmbH & Co. KG CY - Berlin AN - OPUS4-47337 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Baeßler, Matthias A1 - Babutzka, Martin A1 - Trappe, Volker T1 - Vorstellung des Aktivitätsfelds Erneuerbare Energie N2 - Auf der Beiratssitzung des TF Energie wurde das Aktivitätsfeld Erneuerbare Energien in seinem breiten Spektrum (aber selektive Auswahl) vorgestellt. T2 - Beiratssitzung TF Energie CY - BAM Berlin-Adlershof, Germany DA - 09.04.2019 KW - Erneuerbare Energien KW - Windenergie PY - 2019 AN - OPUS4-47751 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Simon, Patrick T1 - Untersuchungsmethoden klimatisch belasteter Bauteile - Projektupdate BAM N2 - Kontinuierliche Sensorbasierte Bauwerksmessungen leisten einen wichtigen Beitrag zur Sicherheit von Verkehrsbauwerken. Hierzu werden im Vorhaben AISTEC Referenzbauwerke und Referenzverfahren untersucht mit Schwerpunkt auf den Einfluss klimatischer Bedingungen. Der Vortrag stellt den aktuellen Projektstand des FB 7.2 vor. T2 - Erstes Verbundtreffen AISTEC CY - Weimar, Germany DA - 21.03.2019 KW - Structural Health Monitoring KW - Environmental Effects KW - Climate Chamber KW - Brücken KW - SHM KW - Klimakammer PY - 2019 AN - OPUS4-47702 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Pirskawetz, Stephan T1 - Überwachung von Stahlbetonbrücken - Ein Modellprojekt N2 - Die Brücken im Netz der Bundesverkehrswege sind überwiegend in einem ausreichenden bis guten Zustand. Allerdings steigt der Unterhalts- und Sanierungsaufwand aufgrund des inzwischen hohen Alters vieler Brücken sowie des ständig wachsenden Schwerlastverkehrs. Techniken zur Einschätzung der verbleibenden Lebensdauer von Brücken sowie zur dauerhaften Beobachtung des Tragverhaltens bzw. des Erfolges von Sanierungsmaßnahmen werden daher für den sicheren und wirtschaftlichen Betrieb dringend benötigt. Zur Evaluierung dafür geeigneter holistischer Ansätze wurde in der BAM das Projekt BLEIB - Bewertung, Lebensdauerprognose und Instandsetzung von Brückenbauwerken - ins Leben gerufen. Ein zentrales Ergebnis des Projektes ist eine extern vorgespannte Stahlbetonbrücke als Zweifeldträger mit einer Gesamtlänge von 24 m, die für den Test verschiedenster Sensorsysteme, zur Validierung numerischer Modelle und zur Erprobung von Sanierungs- und Verstärkungsmaßnahmen entwickelt wurde. Für die Simulation unterschiedlicher Schädigungsgrade kann die Vorspannung der Brücke variiert werden. Die Brücke wird mit beweglichen Gewichten belastet und über einen Shaker zum Schwingen angeregt. Das Brückenmodell wurde bewusst geschädigt, indem die Vorspannung der Struktur erstmalig schrittweise bis auf null reduziert wurde. Unter der Eigenlast verformte sich die Brücke, wodurch eine Rissbildung im Beton einsetzte. Die Zugspannung, die zuvor durch die Vorspannung aufgenommen wurde, übernahm Schritt für Schritt der Beton. Als die Zugspannungen die relativ geringe Zugfestigkeit des Betons überstiegen, begann dieser zu reißen und die schlaffe Bewehrung der Struktur nahm die Spannungen auf. Dieser Versuch wurde unter anderem von Schallemissionsmessungen begleitet. Der Rissbildungsprozess konnte damit, bei gleichzeitiger Aufzeichnung der Vorspannung, früh detektiert und die Risse geortet werden. Die Ergebnisse korrelieren gut mit den Ergebnissen der stereophotogrammetrischen Verformungsmessungen der Struktur. T2 - 22. Kolloquium Schallemission und 3. Anwenderseminar Zustandsüberwachung mit geführten Wellen CY - Karlsruhe, Germany DA - 27.03.2019 KW - Brückenmonitoring KW - Schallemissionsanalyse PY - 2019 AN - OPUS4-47774 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - RPRT A1 - Recknagel, Christoph A1 - Spitzer, Stefan A1 - Hoppe, Johannes A1 - Wenzel, Norman A1 - Pirskawetz, Stephan T1 - Optimierung von Fugensystemen - Messtechnische Grundlagen zur Ermittlung realer Beanspruchungen in situ N2 - Voraussetzung zur Aufklärung von Fugenbewegungen in hochbeanspruchten Verkehrsflächen aus Beton ist ein neues, innovatives und sensitives Sensorsystem, welches unter den Bedingungen der Autobahnpraxis schnell und sicher in entsprechend beanspruchte Bereiche installiert werden kann und in der Lage ist, stabile und hochaufgelöste Bewegungen in mehrere Raumrichtungen zu erfassen. Das durch die BAM neu entwickelte Sensorsystem ist geeignet, um direkt in die Betonfahrbahndecke integriert zu werden und sowohl über saisonale Messbereiche als auch in hoher Auflösung entsprechende Messwerte online zu erfassen und bereit zu stellen. Das für diesen Zweck entwickelte innovative Sensorsystem kann direkt in die Rollspur auf beiden Seiten der Fuge eingebaut werden und ist dafür ausgelegt, Lkw-Überfahrungen zu widerstehen. Es ist schnell und präzise genug, um die realen Bewegungen in allen drei Raumachsen in Echtzeit erfassen zu können. Dieser Forschungsbericht beschreibt das Funktions- und Wirkschema des Sensorsystems und seine Validierung im Labor- und Feldmaßstab. Dabei wird insbesondere auch die praxisgerechte Einbau- und Nutzungsmethodik vorgestellt. Auflösungsvermögen, Robustheit und Nutzerfreundlichkeit werden am Beispiel einer Konzeptstudie auf dem Testgelände DuraBASt erprobt. Es werden grundlegende Hinweise auf den dringlichen Bedarf einer gebrauchsgerechten Beschreibung des realen Verhaltens des Bauwerks Betonstraße identifiziert. Die mit dem Sensorsystem gewonnenen Daten können eine Grundlage für die Konzeption einer performance-basierten Bewertung von Fugenfüllsystemen in Betondecken von Bundesautobahnen bieten. Sie sind geeignet, die Funktionsmechanismen der verschiedenen Betonfahrbahnkonstruktionen besser zu verstehen und zielgerichtet konstruktive und materialtechnische Optimierungen und Fortentwicklungen von Fugenkonstruktionen und Fugenfüllsystemen in gebrauchsbezogener Weise zu entwickeln. Durch weitere Datenerhebung, -fusion und -analyse können Instandsetzungsintervalle und Lebensdauerzyklen besser abgeschätzt und geplant werden. KW - Betonfahrbahndecke KW - Fugen KW - Quantifizierung realer Verformungen PY - 2021 SN - 978-3-95606-590-3 SN - 0943-9323 VL - Straßenbau Heft S 153 SP - 1 EP - 173 PB - Fachverlag NW in der Carl Ed. Schünemann KG CY - Bremen AN - OPUS4-54174 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Jafari, Abbas T1 - Stochastic parameter estimation of a gradient-enhanced damage material model of concrete using variational Bayesian inference N2 - A gradient-enhanced damage material model for concrete simulated by means of the finite element (FE) method is calibrated with respect to important parameters of the involved constitutive law by using the Variational Bayesian method. T2 - UNCECOMP - 4th International Conference on Uncertainty Quantification in Computational Sciences and Engineering CY - Online meeting DA - 28.06.2021 KW - Stochastic model updating KW - Variational Bayesian KW - Gradient-enhanced damage KW - Concrete PY - 2021 AN - OPUS4-54034 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Jafari, Abbas T1 - Variational Bayesian inference of a gradient-enhanced damage material model N2 - A finite element model is calibrated in terms of parameters of the constitutive law; namely the gradient damage model. The method of Variational Bayesian is used for this purpose. The study has been done based on synthetic data. T2 - YIC Young Investigators Conference CY - Online meeting DA - 07.07.2021 KW - Stochastic inference KW - Material model updating KW - Variational Bayesian KW - Gradient-enhanced damage PY - 2021 UR - https://yic2021.upv.es/ AN - OPUS4-54033 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Recknagel, Christoph A1 - Spitzer, Stefan A1 - Hoppe, Johannes A1 - Wenzel, Norman A1 - Pirskawetz, Stephan T1 - Innovative Sensorik für Fugensysteme N2 - Die zielgerichtete Weiterentwicklung von Bauteilen und Konstruktionselementen im Straßenbau hochbeanspruchter Verkehrswege unserer Infrastruktur (Bundesfernstraßen) erfordert spezielle, bauteiladaptierte technische Möglichkeiten/Sensorik zur Quantifizierung des Gebrauchsverhaltens. Bei Fugen in Verkehrsflächen stellen insbesondere langsam und schnell ablaufende Plattendeformationen infolge jahreszeitlicher und verkehrlicher Beanspruchungen maßgebende Beanspruchungszustände dar. Eine Quantifizierung dieser Einwirkungen hilft bei der Weiterentwicklung sowie auch bei der Bewertung optimierter technischer Lösungen. In Forschung kompakt 17/21 „Innovative Sensorik für Fugensysteme“ wird eine neuartige, robuste Lösung der BAM zur Datenerfassung und Bauwerksmonitoring von hochbeanspruchten Verkehrsflächen aus Beton vorgestellt. KW - Betonfahrbahndecke KW - Fugen KW - Quantifizierung realer Verformungen PY - 2021 VL - 17 SP - 1 EP - 2 PB - Eigenverlag der BASt CY - BASt, Bergisch Gladbach AN - OPUS4-54115 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Unger, Jörg F. T1 - Digital twins for monitoring purposes - uncertainty, model bias and model order reduction N2 - A safe and robust performance is a key criterion when building and maintaining structures and component. Ensuring this criterion at different stages of the lifetime can be supported by applying continuous monitoring concepts. The latter usually can serve multiple purposes, including the determination of material parameters for the design phase, the evaluation of the actual loading/environmental conditions (instead of using conservative estimates that are usually larger) and evaluating or predicting the true performance of the structure (thus decreasing the model bias). In this context, a digital twin of the structure has many benefits. It allows to introduce virtual sensors to “measure” sensor information that is e.g. inaccessible or unmeasureable. In order to efficiently use monitoring techniques in the context of a digital twin, it is important to consider the complete chain of information including the choice of sensors, the data processing and structuring, the modelling assumptions, the numerical simulation and finally the stochastic nature of the model prediction. In this presentation, challenges in this context are discussed with a specific focus on Bayesian model updating of the digital twin, accounting for both parameter updates as well as model bias that results from the limitations of modelling assumption. A bottleneck in this approach is the computational effort related to sampling methods such as Markov chain Monte Carlo methods that require many evaluations of the forward model. An alternative to the expensive computation of the forward model for updating the digital twin is the combination with model reduction techniques such as the Proper General Decomposition [1, 2]. The results are illustrated for several examples and scale, ranging from digitals twin for material tests in the lab over lab scale structural digital twins up to damage identification in field experiments. T2 - MMLDT-CSET 2021 Mechanistic Machine Learning and Digital Twins for Computational Science, Engineering & Technology CY - San Diego, CA, USA DA - 26.09.2021 KW - Digital twin for monitoring purposes KW - Model bias KW - Model order reduction PY - 2021 AN - OPUS4-53881 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Mundra, Shishir A1 - Hüsken, Götz A1 - Kühne, Hans-Carsten ED - Sena-Cruz, J. ED - Correia, L. ED - Azenha, M. T1 - Electrochemical realkalisation of carbonated "Dalle de Verre" windows N2 - Concrete-glass windows or commonly referred to as “Dalle de Verre” windows are prevalent in historical monuments across Europe. “Dalle de Verre” windows were made by placing cut stained glasses, of various shapes and sizes, into a steel reinforced concrete frame. In addition to the steel reinforcement, a few steel wires run across the concrete elements to hold the glass windows into place. Much of these structures have been damaged due to carbonation of the thin concrete covers and consequent corrosion of the steel reinforcement; and exhibit several cracks due to the expansive nature of corrosion products formed at the steel–concrete interface. This study focussed on understanding the efficacy of electrochemical realkalisation in reinstating the passive state of the steel reinforcement embedded in such concrete glass windows. Simulant “Dalle de Verre” windows (representative of windows at Kaiser-Wilhelm Gedächtniskirche) were produced using different cements with a water/cement ratio of 0.6 and carbonated under accelerated conditions. Post carbonation, the concrete glass windows were electrochemically realkalised using a sacrificial anode. The influence of highly alkaline conditions due to electrochemical realkalisation on the glass-concrete interface has also been investigated. This study shows that the passive state of the steel reinforcement in “Dalle de Verre” windows, particularly at the Kaiser-Wilhelm Gedächtniskirche (memorial church) in Berlin, can be reinstated using the electrochemical realkalisation method. T2 - 3rd RILEM Spring Convention and Conference (RSCC 2020) CY - Online meeting DA - 10.03.2020 KW - Electrochemical realkalisation KW - Carbonation KW - Concrete-glass windows KW - Passivation KW - Dalle-de-verre PY - 2021 SN - 978-3-030-76465-4 DO - https://doi.org/10.1007/978-3-030-76465-4_15 SN - 2211-0844 VL - RILEM bookseries 34 SP - 163 EP - 171 PB - Springer CY - Cham AN - OPUS4-54299 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Weise, Frank T1 - Zerstörungsfreie Strukturaufklärung antiker Baudenkmäler des Pergamonmuseums N2 - Das Pergamonmuseum ist eines der am meisten besuchten Museen Berlins. Es wird seit etwa 20 Jahren im Rahmen des 1999 von der Stiftung Preußischer Kulturbesitz beschlossenen Masterplans Museumsinsel schrittweise grundhaft instandgesetzt und um einen weiteren Flügel ergänzt, der 2025 fertig gestellt sein soll. In diesem Kontext wurde auch kurz nach dem Beschluss des Masterplans eine Bauzustandsanalyse an den in Originalgröße in der Antikensammlung ausgestellten Baudenk¬ mälern durchgeführt. Allerdings stellte man dabei fest, dass herkömmliche Erkundungsverfahren wie die Bauaufnahme, die baugeschichtliche Untersu¬ chung, das Quellenstudium sowie die äußerliche Begutachtung nicht ausreichen, um die innere Struktur der antiken Baudenkmäler hinreichend zu charakterisieren. Deshalb wurde die BAM im Jahr 2003 von der ARGE Pfanner Pergamonmuseum beauftragt, in enger Zusammenarbeit mit zwei Ingenieurbüros, dem Ingenieurbüro Patitz (IGP) und der Gesellschaft für geophysikalische Unter¬ suchungen mbH (GGU) unter Hinzuziehung einer Restauratorin, die innere Struktur ausgewählter an¬ tiker Baudenkmäler zerstörungsfrei zu untersuchen. Das Ziel der zerstörungsfreien Strukturaufklärung zum inneren Aufbau der Bauteile war es, einerseits sicherheitsrelevante Informationen für die statische Nachweisführung bereitzustellen, sowie andererseits eine Planungsgrundlage für die eventuell erforder¬ liche Ertüchtigung der Baudenkmäler zu schaffen. Im Fokus der Untersuchungen standen dabei das Markttor von Milet und das Säulenjoch der Heiligen Halle am Markt von Priene1 • Im nachstehenden Beitrag werden exemplarisch die am Markttor von Milet durchgeführten Untersuchungen vorgestellt. T2 - Workshop zur Kulturguterhaltung CY - Berlin, Germany DA - 17.11.2021 KW - Bauzustandsanalyse KW - Radar KW - Radiografie PY - 2021 AN - OPUS4-54458 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Stohl, Leonie T1 - Bioreceptivity of Concrete Facades N2 - In recent years, the demand for new and sustainable products has been constantly rising. Especially cementitious materials are known for their high carbon footprint and novel approaches will be needed to counterbalance that. The BAM departments 7.1 (building materials) and 4.0 (Material and the environment) try to improve the sustainability of concrete panels by establishing a biofilm on the weather protection layer. Using an ultra-high-performance-concrete allows the production of very thin facade tiles with a small carbon footprint. Furthermore, the durability of these tiles is expected to surpass the one of “normal” concrete facades and offer the possibility of modular renewing of defective tiles instead of a wall, or even remodeling a whole building. The controlled application of biofilms on facades aims to improve biodiversity, microclimate, and air quality in cities. Furthermore, the greening of typically gray surfaces could improve the mental health of the residents. The project focuses on testing a multiplicity of concrete samples, varying e.g., in roughness or pH. The bioreceptivity is analyzed via laboratory tests, as well as in perennial outdoor experiments. T2 - Biology versus building materials: from biocides to bio-receptivity CY - Online meeting DA - 08.02.2022 KW - Bioreceptivity KW - Algea KW - Concrete KW - Biofilm PY - 2022 AN - OPUS4-54470 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Weise, Frank A1 - Patitz, G. A1 - Redmer, B. A1 - Hübner, M. T1 - Zerstörungsfreie Strukturaufklärung antiker Baudenkmäler des Pergamonmuseums N2 - Das Pergamonmuseum ist eines der am meisten besuchten Museen Berlins. Es wird seit etwa 20 Jahren im Rahmen des 1999 von der Stiftung Preußischer Kulturbesitz beschlossenen Masterplans Museumsinsel schrittweise grundhaft instandgesetzt und um einen weiteren Flügel ergänzt, der 2025 fertig gestellt sein soll. In diesem Kontext wurde auch kurz nach dem Beschluss des Masterplans eine Bauzustandsanalyse an den in Originalgröße in der Antikensammlung ausgestellten Baudenk¬ mälern durchgeführt. Allerdings stellte man dabei fest, dass herkömmliche Erkundungsverfahren wie die Bauaufnahme, die baugeschichtliche Untersu¬ chung, das Quellenstudium sowie die äußerliche Begutachtung nicht ausreichen, um die innere Struktur der antiken Baudenkmäler hinreichend zu charakterisieren. Deshalb wurde die BAM im Jahr 2003 von der ARGE Pfanner Pergamonmuseum beauftragt, in enger Zusammenarbeit mit zwei Ingenieurbüros, dem Ingenieurbüro Patitz (IGP) und der Gesellschaft für geophysikalische Unter¬ suchungen mbH (GGU) unter Hinzuziehung einer Restauratorin, die innere Struktur ausgewählter an¬ tiker Baudenkmäler zerstörungsfrei zu untersuchen. Das Ziel der zerstörungsfreien Strukturaufklärung zum inneren Aufbau der Bauteile war es, einerseits sicherheitsrelevante Informationen für die statische Nachweisführung bereitzustellen, sowie andererseits eine Planungsgrundlage für die eventuell erforder¬ liche Ertüchtigung der Baudenkmäler zu schaffen. Im Fokus der Untersuchungen standen dabei das Markttor von Milet und das Säulenjoch der Heiligen Halle am Markt von Priene1 • Im nachstehenden Beitrag werden exemplarisch die am Markttor von Milet durchgeführten Untersuchungen vorgestellt. T2 - Workshop Kulturguterhaltung - Vom Dampfkessel zu Nanomaterialien CY - Berlin, Germany DA - 17.11.2021 KW - Bauzustandsanalyse KW - Radar KW - Radiografie PY - 2021 SN - 2567-1251 VL - 3 SP - 47 EP - 57 PB - Druckerei G. Bohm CY - Berlin AN - OPUS4-54460 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - van Beek, F. A1 - Kuijper, P. A1 - Voskuilen, J. A1 - Hean, S. A1 - Recknagel, Christoph A1 - Mookhoek, S. D. A1 - van Vliet, D. T1 - Guidlines for flexible joint transition systems RTD 1007-4:2020 N2 - Flexible joint transition systems in the form of bituminous joint transitions, type 4.1a according to RTD1007-1, have been used in the Netherlands with varying success. The lifespan in practice was found to vary greatly: between 1 and 5 years. This is too short a lifespan in relation to the lifespan of the layers of asphalt pavement. Ideally, the replacement of these bituminous joint transitions should take place simultaneously as the maintenance of the asphalt layers. In the meantime, research has been carried out nationally and internationally into improving the life span of bituminous joint transitions. In Germany and Switzerland, the regulations have been shown to lead to a life span of more than 10 years. On this basis, ETAG032-3 was established in the context of EOTA in 2013. In a competition "Silent sustainable joint transitions" held by the Dutch Directorate-General for Public Works and Water Management in the period 2007-2012, three flexible bituminous joint transitions have already been tested, two of which were ultimately found to be suitable. These have been included in the multi-choice matrix (RTD 1007-1) as concept 4.1b (anchored bituminous joint transition) and 4.1c (unanchored bituminous joint transition with stretch-spreading inlay and poured asphalt edge beams). Monitoring these joint transitions in practice over the past 8 years has shown that the desired life span is achievable with these improved joint transitions. It is expected that the improvement in life span achieved abroad can also be realised in the Netherlands if several aspects specific to the Netherlands are taken into account:  For large parts of the Dutch main road network, the traffic intensity of 500,000 heavy vehicles per year assumed in the ETAG032-3 is insufficient. This is a factor 4 to 5 higher on the busiest main roads in the Netherlands.  On 90% of the Dutch main road network, in contrast to countries such as Germany and Switzerland, an open layer (ZOAB (zeer open asfaltbeton [very open asphalt concrete])) is used.  In the Netherlands, in contrast to countries such as Germany and Switzerland, bridges and viaducts are made on a large scale of prefabricated beams and 'floating' support systems that consist entirely of rubber supports that can be deformed all-round. Such constructions have a less favourable, high-frequency deformation behaviour under traffic load.  In Germany and Switzerland, a minimum joint mass temperature of -20 °C is assumed to test bituminous joint transitions. For the Netherlands, -15 °C is assumed, which has a favourable effect. The present second version of RTD 1007-4 is a guideline for the development and realisation of a new generation of more durable flexible joint transitions with a minimum design life of 10-15 years and is a guideline for contractors to demonstrate that a flexible joint transition system meets the requirements as set out in the Directorate-General for Public Works and Water Management guideline RTD 1007-2. KW - Technical rule KW - Approval requirements KW - Extension joints KW - Highway pavements PY - 2020 VL - Version 2.0 SP - 1 EP - 77 CY - Rijkswaterstaat AN - OPUS4-54599 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Weise, Frank A1 - Fladt, Matthias A1 - Wieland, M. T1 - Internal water-repellent treatment - a novel strategy for mitigating alkali-aggregate reaction in concrete pavements N2 - To prevent future alkali-aggregate reaction (AAR) damage, which has occurred frequently in the Germanhighway network in recent years, a new regulation has been drafted. This regulation severely limits the use of alkali-sensitive aggregates by requiring that their suitability be verified by certified inspectors using newly developed AAR concrete tests that involve the external supply of alkali. This has led to a significant limitation in the number of aggregates usable for concrete pavements. A novel AAR avoidance strategy is now being pursued, which aims to enable the use of borderline alkali-sensitive aggregates through the application of an internal water-repellent treatment. The addition of water repellents during concrete production should significantly reduce the ingress of water and external de-icing salts into the concrete pavement, thus reducing the potential for AAR damage. This paper presents the results of laboratory tests to assess the suitability of this new AAR prevention strategy. Representative, highly AAR-susceptible road paving concrete made with an alkali- sensitive greywacke and various water repellents were used as the basis for these experiments. The tests for concrete suitability included determining the conventional fresh and hardened concrete properties as well as concrete prism tests with external alkaline supply. Building on these results, laser-induced breakdown spectroscopy (LIBS) analyses of de-icing-salt intrusion as well as microscopic examinations for verification of the AAR characteristics were carried out. The results of the AAR concrete tests with external alkaline supply support the conclusion that, when hydrophobic agents containing a suitable active ingredient are used, the AAR damage process in road paving concrete can be sufficiently prevented. T2 - 16th International Conference on Alkali-Aggregate Reaction in Concrete CY - Lisboa, Portugal DA - 31.05.2022 KW - Concrete pavements KW - Internal water-repellent treatment KW - Preventive measures KW - Testing for potential AAR PY - 2021 SN - 978-972-49-2315-4 VL - 1 SP - 511 EP - 524 AN - OPUS4-54551 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kositz, M. A1 - Hünger, K.-J. A1 - Weise, Frank T1 - Regression analysis of ASR expansions and silica dissolution in the presence of NaCl N2 - The durability of concrete structures due to alkali-silica-reaction (ASR) is usually been assessed by ASR concrete prism tests (CPT). Therefore, the expansion of concrete specimens indicates an alkalisensitivity. In Germany these tests are performed at 40°C or accelerated 60°C. Nevertheless, ASR prism tests are expensive, power and time-consuming. For these reasons, an alternative chemical test (“mod. BTU-test”) was developed in the past. The “mod. BTU-test” was correlated with German standard CPT. In this test, the solubility of silica and alumina in the liquid phase is measured by ICP-OES. For special requirements in concrete road construction, stricter test procedures are necessary. The specimens are repeatedly subjected to cyclic alternating storage in NaCl. On the one hand, the presence of NaCl increases the ASR expansion, on the other hand NaCl also changes the dissolution behaviour of silica and alumina. For now is not possible to correlate the solubilities of “mod. BTU-test” and ASR expansions influenced by NaCl. Therefore, four aggregates with different ASR sensitivities were chosen and ASR concrete prism tests (in addition with NaCl) have been performed. According to the “mod. BTU-test” the solubilities of silica and alumina in presence of different NaCl concentrations were measured. This paper is about the regression analysis of silica and alumina dissolution and ASR expansion tests in presence of NaCl. The regression analysis shows the influence of a quasi-continuous and an interrupted cyclic alternating storage. Additionally the effects of temperature and NaCl concentration are investigated. In the end, a suitable NaCl concentration of the “mod. BTU-test” for dissolution experiments is recommended. The “mod. BTU-Test” with NaCl might be a serious and reliable test method for ASR classification for concrete road construction. T2 - 16th International Conference on Alkali-Aggregate Reaction in Concrete CY - Lisboa, Portugal DA - 31.05.2022 KW - Alkali silica reaction KW - Alkaline solution KW - Alumina & silica dissolution KW - NaCl KW - Regression analysis PY - 2021 SN - 978-972-49-2315-4 VL - 1 SP - 711 EP - 723 AN - OPUS4-54552 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Krütt, Enno A1 - Pirskawetz, Stephan A1 - Wallau, Wilma A1 - Meng, Birgit T1 - Development of an automated 60 °C Concrete Prism Test N2 - ln most of the ASR-test procedures, the expansion of concrete or mortar specimens is used as an indicator to assess the ASR-potential of an aggregate or a specific concrete mix. For these tests, the specimens are stored in an ASR-provoking environment, where the reaction is accelerated by elevated temperature and humidity. To measure the length change, the storage must be interrupted for at least a few minutes. Düring the 60 °C Concrete Prism Test (60 °C-CPT), the specimens are cooled down to 20 °C for 24 hours, to ensure the same hygrothermal conditions for every measurement. This limits the number of measurements during the test period and may lead to additional effects, that probably influence the expansion development. With a recently developed device, it is possible to continuously monitor the expansion ofprisms without interrupting the ASR-provoking storage. Due to the dense database of this automated test, the results can contribute to a better understanding of the ASR-process. This study compares results of the automated and conventional 60 °C-CPT. Tests of different aggregates showed, that the results of the automated and conventional test are consistent, but the expansions during the conventional test are generally higher. Preliminary results led to the conclusion, that the cooling for the measurements leads to additional expansions. Therefore, a modified threshold should be discussed for the automated 60 °C-CPT. T2 - 16th International Conference on Alkali-Aggregate Reaction in Concrete CY - Lisboa, Portugal DA - 31.05.2022 KW - 60 °C-CPT KW - ASR expansion monitoring KW - Automated testing PY - 2021 SN - 978-972-49-2315-4 VL - 1 SP - 789 EP - 799 AN - OPUS4-54553 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Fladt, Matthias T1 - Utilisation of alkali-sensitive aggregates for concrete pavements by internal hydrophobisation N2 - In order to avoid the increased ASR damage to concrete pavements in the German motorway network in the future, the ARS 04/2013 introduced mandatory suitability tests to exclude alkali-sensitive aggregates in new construction measures. This resulted in a significant reduction of suitable aggregates. Against this background, borderline alkali-sensitive aggregates are to be made usable by adding an internal water repellent agent during concrete casting. The ASR avoidance strategy is based on the significant reduction of the penetration of water and de-icing salt solution into the concrete pavement. Laboratory tests show that, with a suitable active ingredient, the ASR damage process can be significantly reduced with internal hydrophobisation. The disadvantage is that this is associated with a deterioration of the mechanical properties and the resistance to freeze-thaw with de-icing salt. The aim of the ongoing research is to reduce these disadvantages through targeted modification of the hydrophobising agent and air-entraining agent. T2 - European Coatings Show CY - Online meeting DA - 13.09.2021 KW - Concrete pavement KW - Alkali-Silica-Reaction KW - Hydrophobisation KW - Preventive measure PY - 2021 AN - OPUS4-54549 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Herrmann, Ralf T1 - Digitalisierung sichert die Bauwerke von gestern und das Wissen von morgen N2 - Die moderne Gesellschaft in Deutschland und Europa profitiert von der hervorragenden baulichen Infrastruktur, die für uns viele Aspekte aus den Bereichen Mobilität, Energieversorgung, Transport, Umweltschutz, (Nah-)Erholung und Gefahrenabwehr zur Alltäglichkeit werden lassen und uns ein hohes Gefühl der technischen Sicherheit vermitteln. Viele der Annehmlichkeiten, wie beispielweise ein Hochgeschwindigkeitseisenbahnverkehrsnetz, zuverlässige Stromversorgung im europäischen Verbundsystem und ein immenser Personen-, Güter- und Warenverkehr auf der Straße, zu Wasser und in der Luft ist ohne eine leistungsfähige, resiliente und zuverlässige bauliche Infrastruktur undenkbar. KW - Bauwerksmonitoring KW - Bauwerksdiagnostik KW - Digitalisierung PY - 2022 DO - https://doi.org/10.1002/bate.202270303 SN - 1437-0999 SN - 0932-8351 VL - 99 IS - 3 SP - 161 EP - 162 PB - Ernst & Sohn GmbH CY - Berlin AN - OPUS4-54557 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Recknagel, Christoph A1 - Hoppe, Johannes A1 - Eilers, M. T1 - Technische Lieferbedingungen für die Dichtungsschicht aus einer Polymerbitumen-Schweißbahn zur Herstellung von Brückenbelägen auf Beton TL/TP-ING - Teil 7: Brückenbeläge, Abschnitt 1 N2 - In den "Technischen Lieferbedingungen für die Dichtungsschicht aus einer Polymerbitumen-Schweißbahn zur Herstellung von Brückenbelägen auf Beton" (TL BEL-B 1) sind die Regelungen über die erforderlichen Voraussetzungen zur Verwendung von Polymerbitumen-Schweißbahnen zur Ausbildung einer Dichtungsschicht aus einer einlagigen Polymerbitumen-Schweißbahn auf Beton aufgeführt. Sie umfassen den grundsätzlichen Nachweis der Funktionsfähigkeit und Dauerhaftigkeit sowie die Sicherstellung des nachgewiesenen Qualitätsniveaus. KW - Brückenbeläge KW - Asphaltbauweise KW - PmB Schweißbahn KW - Technische Anforderungen PY - 2022 SN - 978-3-86446-325-9 VL - 783/1 SP - 1 EP - 8 PB - FGSV Verlag GmbH CY - Köln AN - OPUS4-54853 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Weise, Frank T1 - Begutachtung Berliner Tuffsteinfassaden - Turmruine der Kaiser-Wilhelm-Gedächtniskirche und Charlottenburger Tor N2 - Am Ende des 19. und zu Beginn des 20. Jahrhunderts wurden auch in Berlin vermehrt Fassadenverblendung aus Eifeler Tuffsteinen errichtet. Die Eifeler Tuffsteine zeichnen sich aufgrund ihrer hohen Porosität einerseits durch eine gute Verarbeitbarkeit aus. Andererseits sind sie nur schwach gebunden und besitzen deshalb eine geringe Verwitterungsbeständigkeit. T2 - Workshop zur Kulturguterhaltung CY - Berlin, Germany DA - 17.11.2021 KW - Fassade KW - Tuffstein KW - Schalenbildung PY - 2021 AN - OPUS4-54633 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Unger, Jörg F. T1 - Combining Data and Simulation Models in real time - A Digital Twin for Bridge monitoring N2 - Im Rahmen des Vortrages wurde das Konzept eines digitalen Zwillings vorgestellt und an verschiedenen Beispielen angefangen von einem Laborversuch über Kleinversuche bis zum Realmaßstab dargestellt. N2 - During the lecture, the concept of a digital twin was presented and illustrated with various examples starting from a laboratory experiment to small-scale and real-scale experiments. T2 - EURAD Second Annual Event (2022) CY - Online meeting DA - 28.03.2022 KW - Digital Twin KW - Bridge Monitoring KW - Simulation Models PY - 2022 UR - https://igdtp.eu/event/eurad-annual-event-2/ AN - OPUS4-54639 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Denkler, Tilman T1 - The Metabuilding Labs approach to Quality Assurance – Results of Task 8.4 & Task 8.5 N2 - The finalization of the Standard Operating Procedures and Work Instructions for the O3BETs is described. The setuo of the internal system for quality checks is outlined. Major achievements are shown and future work is adressed. T2 - 7th General Meeting Metabuilding Labs CY - Bordeaux, France DA - 20.5.2025 KW - Metabuilding Labs KW - Open innovation test bed KW - Quality management PY - 2025 AN - OPUS4-63299 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Eichner, Lukas A1 - Schneider, Ronald A1 - Simon, Patrick A1 - Baeßler, Matthias T1 - Optimal sensor placement for vibration-based structural health monitoring obtained via value of information analysis as part of a digital structural integrity management of offshore structures N2 - A digital structural integrity management of offshore structures enables an optimized planning of inspections and repairs with risk-based methods. In a risk-based approach, the inspection and repair strategy that minimizes the expected lifetime costs consisting of the expected inspection, repair and failure costs is determined. In addition to inspections, information on the structural condition can be continuously obtained by monitoring the vibration response of the structural system. Changes in the vibration characteristics quantified in terms of modal properties can be an indication of structural damage. In risk-based inspection and repair planning, the effect of monitoring results is determined via Bayesian updating of the structural condition and reliability. This information should be applied to inform decisions on inspections and may result in a reduced inspection effort. The benefit of continuously monitoring the structural health can be quantified in terms of the value of information, which corresponds to the difference between the expected lifetime costs with and without monitoring. In this work, we demonstrate in a numerical example how an optimized sensor placement for a vibration-based structural health monitoring system can be determined by maximizing the value of information. T2 - 3rd International Conference on Health Monitoring of Civil & Maritime Structures (HeaMES 2022) CY - Online meeting DA - 08.06.2022 KW - Structural Health Monitoring KW - Value of Information KW - Offshore Wind Energy KW - Optimal Sensor Placement KW - Bayesian System Identification PY - 2022 UR - https://www.researchgate.net/publication/362569906_Optimal_sensor_placement_for_vibration-based_structural_health_monitoring_obtained_via_value_of_information_analysis_as_part_of_a_digital_structural_integrity_management_of_offshore_structures SN - 978-1-8383226-7-0 SP - 23 EP - 32 AN - OPUS4-55465 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Titscher, Thomas T1 - Model calibration and damage detection for a digital twin N2 - Numerical models are an essential tool in predicting and monitoring the behavior of civil structures. Inferring the model parameters is a challenging tasks as they are often measured indirectly and are affected by uncertainties. Digital twins couple those models with real-world data and can introduce additional, systematic sensor uncertainties related to the sensor calibration, i.e. uncertain offsets and calibration factors. In this work, the challenges of data processing, parameter identification, model selection and damage detection are explored using a lab-scale cable stayed bridge demonstrator. By combining force measurements in the cables with displacement measurements from both laser and stereo-photogrammetry systems, the elastic parameters of a three-dimensional finite element beam model are inferred. Depending on the number of sensors and the number of datasets used, parametrizing the sensor offsets and factors, leads to model with over 100 parameters. With a real-time solution of the problem in mind, a highly efficient analytical variational Bayesian approach is used to solve it within seconds. An analysis of the required assumptions and limitations of the approach, especially w.r.t. to the computed evidence, is provided by a comparison with dynamic nested sampling in a simplified problem. Finally, by inferring the value of additional damage parameters along the bridge, the method is successfully used to detect the location of an artificially introduced weak spot in the demonstrator bridge. T2 - ECCOMAS 2022 CY - Oslo, Norway DA - 05.06.2022 KW - Bayesian identification KW - Digital twin KW - Variational Bayesian KW - Damage detection PY - 2022 AN - OPUS4-55083 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Diercks, Philipp T1 - Multiscale modeling of heterogeneous structures based on a localized model order reduction approach N2 - Many of today’s problems in engineering demand reliable and accurate prediction of failure mechanisms of mechanical structures. Herein, it is necessary to take into account the heterogeneous structure on the lower scale, to capture the underlying physical phenomena. However, this poses a great challenge to the numerical solution as the computational cost is significantly increased by resolving the lower scale in the model. Moreover, in applications where scale separation as the basis of classical homogenization schemes does not hold, the influence of the lower scale on the upper scale has to be modelled directly. This work aims to develop an efficient concurrent methodology to model heterogeneous structures combining the variational multiscale method (VMM) [1] and model order reduction techniques (e. g. [2]). First, the influence of the lower scale on the upper scale can be taken into account following the additive split of the displacement field as in the VMM. Here, also a decomposition of the global domain into subdomains, each containing a fine grid discretization of the lower scale, is introduced. Second, reduced approximation spaces for the upper and lower scale solution are constructed by exploring possible solutions for each subdomain based on a representative unit cell. The local reduced spaces are designed such that local contributions of each subdomain can be coupled in a conforming way. Thus, the resulting global system is sparse and reduced in size compared to the direct numerical simulation, leading to a faster solution of the problem. The authors gratefully acknowledge financial support by the German Research Foundation (DFG), project number 394350870, and by the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (ERC Grant agreement No. 818473). T2 - The 8th European Congress on Computational Methods in Applied Sciences and Engineering (ECCOMAS) 2022 CY - Oslo, Norway DA - 05.06.2022 KW - Multiscale methods KW - Variational multiscale method KW - Domain decomposition KW - Model order reduction PY - 2022 AN - OPUS4-55117 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Tamsen, Erik T1 - Towards an automatic optimization framework for performance oriented precast concrete design N2 - Concrete has a long history in the construction industry and is currently one of the most widely used building materials. Especially precast concrete elements are frequently utilized in construction projects for standardized applications, increasing the quality of the composite material, as well as reducing the required building time. Despite the accumulated knowledge, continuous research and development in this field is essential due to the complexity of the composite combined with the ever-growing number of applications and requirements. Especially in view of global climate change, design aspects as CO2 emissions and resource efficiency require new mix designs and optimization strategies. A result of the material’s high complexity and heterogeneity on multiple scales is that utilizing the full potential with changing demands is highly challenging, even for the established industry. We propose a framework based on an ontology, which automatically combines experimental data with numerical simulations. This not only simplifies experimental knowledge transfer, but allows the model calibration and the resulting simulation predictions to be reproducible and interpretable. This research shows a way towards a more performance oriented material design. Within this talk we present our workflow for an automated simulation of a precast element, demonstrating the interaction of the ontology and the finite element simulation. We show the automatic calibration of our early-age concrete model [1, 2], to improve the prediction of the optimal time for the removal of the form work. T2 - The 8th European Congress on Computational Methods in Applied Sciences and Engineering (ECCOMAS) 2022 CY - Oslo, Norway DA - 05.06.2022 KW - Performance oriented concrete design KW - Early-age concrete KW - Precast concrete KW - Ontology KW - Optimization workflow PY - 2022 AN - OPUS4-55302 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Simon, Patrick A1 - Herrmann, Ralf A1 - Schneider, Ronald A1 - Hille, Falk A1 - Baeßler, Matthias A1 - El-Athman, Rukeia T1 - Research Data Management of Structural Health Monitoring Projects and Subsequent Applications of Artificial Intelligence Methods N2 - Structural health monitoring (SHM) intends to improve the management of engineering structures. The number of successful SHM projects – especially SHM research projects – is ever growing, yielding added value and more scientific insight into the management of infrastructure asset. With the advent of the data age, the value of accessible data becomes increasingly evident. In SHM, many new data-centric methods are currently being developed at a high pace. A consequent application of research data management (RDM) concepts in SHM projects enables a systematic management of raw and processed data, and thus facilitates the development and application of artificial intelligence (AI) and machine learning (ML) methods to the SHM data. In this contribution, a case study based on an institutional RDM framework is presented. Data and metadata from monitoring the structural health of the Maintalbrücke Gemünden for a period of 16 months are managed with the RDM system BAM Data Store, which makes use of the openBIS data management software. An ML procedure is used to classify the data. Feature engineering, feature training and resulting data are performed and modelled in the RDM system. T2 - 11th International Conference on Bridge Maintenance, Safety and Management (IABMAS2022) CY - Barcelona, Spain DA - 11.07.2022 KW - Research data management KW - Structural health monitoring KW - Artificial intelligence PY - 2022 SN - 978-1-032-35623-5 SN - 978-1-003-32264-1 DO - https://doi.org/10.1201/9781003322641-127 SP - 1061 EP - 1068 PB - CRC Press CY - Boca Raton AN - OPUS4-55493 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hille, Falk A1 - Herrmann, Ralf T1 - Structural Health Monitoring am Großen Fallturm der BAM N2 - In diesem Beitrag wird die Structural Health Monitoring Kampagne am Großen Fallturm der BAM vorgestellt. T2 - Seminar "Zerstörungsfreie Prüfung" CY - Online meeting DA - 13.01.2022 KW - Belastungsversuch KW - Großer Fallturm Horstwalde KW - Schwingungsdynamik KW - Modalanalyse PY - 2022 AN - OPUS4-55478 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hille, Falk A1 - Nerger, Deborah A1 - Moosavi, Robabeh A1 - Grunwald, Marcel T1 - Discussion on data evaluation of tomographic and numerical results N2 - The contribution discusses the processing and analysis of data generated on two different ways of investigations for impact damage in reinforced concrete structures. Damage investigations are essential to determine type and characteristics of damage and thus the residual capacity. Damage describing data is generated using two different types of investigation, a non-destructive tomographic as well as numerical examination. Subsequently, data of both sources was merged and analysed. Within the research project “Behaviour of structural components during impact load conditions caused by aircraft fuel tank collision” reinforces concrete plates were damaged by impact loading, see Hering (2020). Afterwards the damaged specimens were investigated tomographically as well as numerically using several methods and models. Aim of the presented research work was to specify an objective comparability of numerical data with experimentally determined damage patterns and based on this, to establish a quantitative damage evaluation. T2 - 26th International Conference on Structural Mechanics in Reactor Technology CY - Potsdam, Germany DA - 10.07.2022 KW - Impact damage on reinforced concrete KW - Tomographic damage evaluation KW - Numerical damage simulation PY - 2022 SP - 1 EP - 8 AN - OPUS4-55474 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hille, Falk T1 - Discussion on data evaluation of tomographic and numerical results N2 - The contribution discusses the processing and analysis of data generated on two different ways of investigations for impact damage in reinforced concrete structures. Damage investigations are essential to determine type and characteristics of damage and thus the residual capacity. Damage describing data is generated using two different types of investigation, a non-destructive tomographic as well as numerical examination. Subsequently, data of both sources was merged and analysed. Within the research project “Behaviour of structural components during impact load conditions caused by aircraft fuel tank collision” reinforces concrete plates were damaged by impact loading, see Hering (2020). Afterwards the damaged specimens were investigated tomographically as well as numerically using several methods and models. Aim of the presented research work was to specify an objective comparability of numerical data with experimentally determined damage patterns and based on this, to establish a quantitative damage evaluation. T2 - 26th International Conference on Structural Mechanics in Reactor Technology CY - Potsdam, Germany DA - 10.07.2022 KW - Impact damage of reinforced concrete KW - Tomographic damage evaluation KW - Numerical simulation of impact damage PY - 2022 AN - OPUS4-55476 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Simon, Patrick T1 - Research Data Management of Structural Health Monitoring Projects and Subsequent Applications of Artificial Intelligence Methods N2 - Structural health monitoring (SHM) intends to improve the management of engineering structures. The number of successful SHM projects – especially SHM research projects – is ever growing, yielding added value and more scientific insight into the management of infrastructure asset. With the advent of the data age, the value of accessible data becomes increasingly evident. In SHM, many new data-centric methods are currently being developed at a high pace. A consequent application of research data management (RDM) concepts in SHM projects enables a systematic management of raw and processed data, and thus facilitates the development and application of artificial intelligence (AI) and machine learning (ML) methods to the SHM data. In this contribution, a case study based on an institutional RDM framework is presented. Data and metadata from monitoring the structural health of the Maintalbrücke Gemünden for a period of 16 months are managed with the RDM system BAM Data Store, which makes use of the openBIS data management software. An ML procedure is used to classify the data. Feature engineering, feature training and resulting data are performed and modelled in the RDM system. T2 - 11th International Conference on Bridge Maintenance, Safety and Management (IABMAS2022) CY - Barcelona, Spain DA - 11.07.2022 KW - Research data management KW - Structural health monitoring KW - Artificial intelligence PY - 2022 AN - OPUS4-55494 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Eichner, Lukas T1 - Optimal sensor placement for vibration-based structural health monitoring obtained via value of information analysis as part of a digital structural integrity management of offshore structures N2 - A digital structural integrity management of offshore structures enables an optimized planning of inspections and repairs with risk-based methods. In a risk-based approach, the inspection and repair strategy that minimizes the expected lifetime costs consisting of the expected inspection, repair and failure costs is determined. In addition to inspections, information on the structural condition can be continuously obtained by monitoring the vibration response of the structural system. Changes in the vibration characteristics quantified in terms of modal properties can be an indication of structural damage. In risk-based inspection and repair planning, the effect of monitoring results is determined via Bayesian updating of the structural condition and reliability. This information should be applied to inform decisions on inspections and may result in a reduced inspection effort. The benefit of continuously monitoring the structural health can be quantified in terms of the value of information, which corresponds to the difference between the expected lifetime costs with and without monitoring. In this work, we demonstrate in a numerical example how an optimized sensor placement for a vibration-based structural health monitoring system can be determined by maximizing the value of information. T2 - 3rd International Conference on Health Monitoring of Civil & Maritime Structures (HeaMES 2022) CY - Online meeting DA - 08.06.2022 KW - Bayesian System Identification KW - Offshore Wind Energy KW - Optimal Sensor Placement KW - Structural Health Monitoring KW - Value of Information PY - 2022 AN - OPUS4-55473 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Simon, Patrick T1 - Sensorbasierte Systemidentifikation N2 - Die aktuelle Instandhaltungsstrategien von Ingenieurbauwerken arbeiten zustandsbasiert und stützen sich auf visuelle Inspektionen in kurzen, starren Intervallen. Beim Übergang zu Predicitive-Maintenance-Strategien können Sensordaten eigesetzt werden um Prognosemodelle der Bauwerke zu aktualisieren. Ein erster Schritt hierzu ist die sensorbasierte Systemidentifikation. T2 - Abschlussveranstaltung AISTEC CY - Berlin, Germany DA - 02.05.2022 KW - Systemidentifikation KW - Strukturmonitoring PY - 2022 AN - OPUS4-55495 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Eichner, Lukas A1 - Gerards, Paul A1 - Herrmann, Ralf A1 - Schneider, Ronald A1 - Hille, Falk A1 - Baeßler, Matthias T1 - A framework for data and structural integrity management for support structures in offshore wind farms based on building information modelling N2 - Support structures of wind turbines in German offshore wind farms are regularly inspected. Currently, inspection outcomes are generally not systematically recorded. This prevents their consistent handling and processing, which is a key requirement to enable an efficient structural integrity management. As part of the DiMoWind-Inspect project, a data model and reference designation system for such inspection results is developed to facilitate their identification, localization, quantification, tracing and linking throughout the lifetime of a wind farm and beyond. The inspection results together with structural health monitoring results and information on repairs form the basis for assessing and predicting the structural condition, estimating the remaining lifetime, and planning of future inspections, structural health monitoring, and repairs. As a basis for developing a digital structural integrity management, a generic framework is proposed in this paper, which describes the stakeholders, data, models, processes and workflows of the integrity management of support structures in offshore wind farms and their interrelations. The framework adopts a building information modelling approach to describe the information relevant to the structural integrity management. The central digital space of the framework is a common data environment. An implementation of the framework will enable a digital structural integrity management in which inspection, structural health monitoring, repair, assessment and planning outcomes generated throughout the life cycle of a wind farm can be consistently collected, managed, shared and processed by the relevant shareholders. T2 - 8th International Symposium on Reliability Engineering and Risk Management CY - Hannover, Germany DA - 04.09.2022 KW - Offshore wind energy KW - support structures KW - structural health monitoring KW - building information modelling KW - structural integrity management PY - 2022 DO - https://doi.org/10.3850/978-981-18-5184-1_MS-04-161-cd SP - 111 EP - 117 PB - Research Publishing CY - Singapore AN - OPUS4-55656 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Eichner, Lukas T1 - A framework for data and structural integrity management for support structures in offshore wind farms based on building information modelling N2 - Support structures of wind turbines in German offshore wind farms are regularly inspected. Currently, inspection outcomes are generally not systematically recorded. This prevents their consistent handling and processing, which is a key requirement to enable an efficient structural integrity management. As part of the DiMoWind-Inspect project, a data model and reference designation system for such inspection results is developed to facilitate their identification, localization, quantification, tracing and linking throughout the lifetime of a wind farm and beyond. The inspection results together with structural health monitoring results and information on repairs form the basis for assessing and predicting the structural condition, estimating the remaining lifetime, and planning of future inspections, structural health monitoring, and repairs. As a basis for developing a digital structural integrity management, a generic framework is proposed in this paper, which describes the stakeholders, data, models, processes and workflows of the integrity management of support structures in offshore wind farms and their interrelations. The framework adopts a building information modelling approach to describe the information relevant to the structural integrity management. The central digital space of the framework is a common data environment. An implementation of the framework will enable a digital structural integrity management in which inspection, structural health monitoring, repair, assessment and planning outcomes generated throughout the life cycle of a wind farm can be consistently collected, managed, shared and processed by the relevant shareholders. T2 - 8th International Symposium on Reliability Engineering and Risk Management CY - Hannover, Germany DA - 04.09.2022 KW - Offshore wind energy KW - Support structures KW - Building information modelling KW - Structural health monitoring KW - Structural integrity maintenance PY - 2022 AN - OPUS4-55651 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Strangfeld, Christoph T1 - Introduction of a monitoring system for Bingham fluids in additive manufacturing with concrete N2 - Freeform additive manufacturing of concrete structures is a rising technology in civil engineering with several fascinating advantages. Nonetheless, to ensure reliability and structural integrity, standards and quality control are required in the future to bring this technology into the market. As the concrete is manufactured continuously, continuous quality control of the printing process is also required, i.e. comprehensive process monitoring. At BAM, a test rig will be installed, enabling the printing of concrete structures with a maximum size of 2 m x 1 m x 1 m (l x w x h). Here, process monitoring is the focus of the test rig. In this study, we show the results of the first pump tests, including the measurement of several parameters such as temperature and pressure along the supply system, i.e. from the concrete pump to the printer head. T2 - NDT-CE 2022 CY - Zurich, Switzerland DA - 16.08.2022 KW - Additive manufacturing of concrete KW - Process monitoring KW - Non-destructive testing KW - Bingham fluid PY - 2022 AN - OPUS4-55637 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schneider, Ronald T1 - Belastungsversuch und Methodenvalidierung an der Maintalbrücke Gemünden N2 - Im Projekt AISTEC wurden Methoden entwickelt, die der prädiktiven Instandhaltung von Ingenieurbauwerken dienen. Zur Validierung dieser Methoden wurden an einem Referenzbauwerk - der Maintalbrücke Gemünden - Belastungstests durchgeführt. T2 - Abschlussveranstaltung AISTEC CY - Berlin, Germany DA - 02.05.2022 KW - Belastungsfahrt KW - GNSS KW - Einflusslinien PY - 2022 AN - OPUS4-55496 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kremberg, Jan A1 - Häßler, Dustin A1 - Stelzner, Ludwig A1 - Hothan, Sascha T1 - Brandversuche an mechanisch belasteten Carbonzuggliedern N2 - Der Beitrag stellt experimentelle Untersuchungen zum Feuerwiderstand von Carbonzuggliedern vor. Die Anwendung von Zuggliedern aus Carbon ist durch die außergewöhnlich gute Ermüdungs- sowie hohe Zugfestigkeit des Werkstoffs motiviert. Ferner ergibt sich gegenüber Stahl eine deutliche Reduzierung des Querschnitts. Perspektivisch sollen damit Stahlzugglieder im Netzwerkbogenbrückenbau ersetzt werden. Durch die Materialsubstitution werden Ressourcen nicht nur beim Zugglied selbst, sondern auch am Gesamttragwerk der Brücke eingespart. Da zum Tragverhalten von Carbonzuggliedern im Brandfall bislang keine Erkenntnisse vorliegen, sollen mit Hilfe von Bauteilbrandversuchen die Versagensmechanismen sowie die grundsätzliche Gleichwertigkeit gegenüber konventionellen Stahlhängern untersucht werden. Der Beitrag beschreibt die Durchführung und die Ergebnisse von Brandversuchen an mechanisch belasteten Carbonzuggliedern. Die realmaßstäblichen Versuche werden am unikalen Zugbauteil-prüfofen der BAM im Mai 2022 durchgeführt. Das Versuchsprogramm umfasst vier Carbonzugglieder mit kreisrunden Querschnitten in zwei verschiedenen Durchmessern, ⌀36 mm und ⌀51 mm. Aus Gründen der Vergleichbarkeit erfolgt die Brandbeanspruchung nach Einheits-Temperaturzeitkurve (ETK). Während des Brandversuches wird die axiale Prüfkraft von 750 kN bzw. 1500 kN bis zum Eintreten des Probenversagens konstant gehalten. Zusätzlich werden die Längsverformung sowie die Bauteil- und Brandraumtemperaturen aufgezeichnet. In einem Vorversuch an einem unbelasteten Bauteilabschnitt eines Carbonzuggliedes konnte das Brand- und Erwärmungsverhalten des Verbundmaterials untersucht werden. Dabei zeigten sich Makrorisse und eine Zersetzung der Kunststoffmatrix sowie eine hohe Temperaturbeständigkeit der Kohlenstofffasern. Durch das Fehlen der schützenden Matrix reagierten die Carbonfasern sensibel auf Querbeanspruchung. Dies führte zu einem Bruch und Ablösen der oberflächennahen Fasern. T2 - 8th Symposium Structural Fire Engineering CY - Brunswick, Germany DA - 13.09.2022 KW - Carbon KW - Zugglied KW - Brandversuch KW - Feuerwiderstand KW - Brandschutz PY - 2022 SP - 1 EP - 13 PB - TU Braunschweig CY - Braunschweig AN - OPUS4-55704 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Klimek, André A1 - Stelzner, Ludwig A1 - Hothan, Sascha A1 - Zehfuß, J. T1 - Auswirkung von passivem Zwang auf das Abplatzverhalten von Beton im Brandfall N2 - Der diesjährige Beitrag zeigt den Einfluss ausgewählter Versuchsrandbedingungen auf das Abplatzverhalten von Normalbeton im kleinskaligen Brandversuch. Im Rahmen der Untersuchungen wurde die Abplatzneigung von acht zylindrischen Betonprüfkörpern der Maße Ø47 cm x 29 cm aus Normalbeton analysiert. Vier Prüfkörper wurden aus Normalbeton mit quarzitischer Gesteinskörnung hergestellt, wohingegen die grobe Gesteinskörnung (>2 mm) der anderen vier Prüfkörper durch Basaltsplitt ersetzt wurde. Neben der Art der groben Gesteinskörnung wurden zusätzlich ausgewählte Versuchsrandbedingungen variiert. Dies umfasste zum einen die Vorlagerung der Prüfkörper bei verschiedenen Umgebungsfeuchten und zum anderen die Ummantelung der Prüfkörper mit zwei Ringen aus Stahl bzw. einem durchgehenden Stahlblech. Die Ummantelung der Prüfkörper mit Stahlringen im Brandversuch führt zu einer Behinderung der thermischen Ausdehnung der Prüfkörper und zum Aufbau thermomechanischer Zwangsdruckspannungen. Diese Zwangsdruckspannungen werden maßgeblich von der thermischen Ausdehnung der verwendeten Gesteinskörnung beeinflusst. Zusätzlich wird die Feuchteabgabe über die Mantelfläche behindert. Der Einsatz des Stahlblechs reduziert lediglich die Abgabe der Feuchtigkeit über die Mantelfläche und induziert vernachlässigbare Zwangsdruckspannungen im Beton. Die Brandbeanspruchung der Prüfkörper erfolgte einseitig nach der Einheits-Temperaturzeitkurve (ETK) über einen Zeitraum von 60 Minuten. Mit Hilfe eines Laser Scanners wurden vergleichende 3D-Messungen der brandbeanspruchten Oberfläche vor und nach dem Brandversuch durchgeführt. Aus diesen Messungen konnten das Abplatzvolumen, die Abplatztiefenverteilung und die maximale Abplatztiefe ermittelt werden. Während des Brandversuchs wurde die Temperaturverteilung im Prüfkörper mittels fünf eingebetteter Mantelthermoelemente in verschiedenen Tiefen bestimmt. Die Ergebnisse zeigen, dass die Abplatzungen an der brandbeanspruchten Oberfläche infolge der Prüfkörperummantelung mit Stahlringen bzw. Stahlblech zunehmen. Bei einer Ummantelung mit Stahlringen mit gleichzeitiger Vortrocknung der Betonrandzone platzt der Prüfkörper mit quarzitischer Gesteinskörnung ab, wohingegen der Prüfkörper mit basaltischer Gesteinskörnung keine Abplatzungen aufweist. Dies wird auf die unterschiedliche Ausprägung der thermomechanischen Schädigung infolge der unterschiedlichen thermischen Ausdehnungskoeffizienten von Quarzkies und Basalt zurückgeführt. Die Ergebnisse der Brandprüfserie zeigen, dass die Variation der Prüfrandbedingungen bei Beibehaltung der Prüfkörpergröße einen maßgeblichen Einfluss auf das Abplatzverhalten haben. Die Randbedingungen sind daher bei kleinskaligen Brandversuchen, die zukünftig als „Screening-Tests“ ersatzweise für kostenintensive Bauteilversuche verwendet werden sollen, zu berücksichtigen. T2 - 8th Symposium Structural Fire Engineering CY - Brunswick, Germany DA - 13.09.2022 KW - Brand KW - Beton KW - Abplatzen KW - Zwang PY - 2022 SP - 1 EP - 12 PB - TU-Braunschweig CY - Braunschweig AN - OPUS4-55731 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kremberg, Jan T1 - Brandversuche an mechanisch belasteten Carbonzuggliedern N2 - Präsentation zu den Ergebnissen des Forschungsprojektes NeZuCa. T2 - 8th Symposium Structural Fire Engineering CY - Brunswick, Germany DA - 13.09.2022 KW - Carbon KW - Brandschutz KW - Feuerwiderstand KW - Brandversuch KW - Zugglied PY - 2022 AN - OPUS4-55705 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Klimek, André T1 - Auswirkung von passivem Zwang auf das Abplatzverhalten von Beton im Brandfall N2 - Beschreibung des Abplatzverhaltens von vier Prüfkörpertypen in Abhängigkeit der Ummantelungsart und Lagerungsbedingungen für zwei Betonrezepturen T2 - 8th Symposium Structural Fire Engineering CY - Brunswick, Germany DA - 13.09.2022 KW - Brand KW - Beton KW - Abplatzen KW - Zwang PY - 2022 AN - OPUS4-55734 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Klimek, André A1 - Stelzner, Ludwig A1 - Hothan, Sascha A1 - Zehfuß, J. T1 - Screening-tests on the susceptibility to spalling of two ordinary concretes N2 - Investigating the spalling behaviour of a concrete mixture using large scale members is complex and expensive. Thus, the susceptibility of concrete to spalling is investigated by means of fire tests on small scale specimens. However, the reduction of the fire exposed surface increases the influence of boundary effects. Macrocracking and the water loss via the lateral surfaces reduce the impact of the thermomechanical and thermohydraulic damage mechanisms and therefore, lower the risk of spalling. Thus, the influence of different restraints on the spalling behaviour of intermediate scaled specimens (Ø=0.47 m; h=0.29 m) was investigated for two ordinary concrete mixtures. Both mixtures had the same composition except the type of aggregate. One mixture contained only quartzitic aggregates, whereas the other mixture was made with basalt grit as coarse aggregates. Applied steel rings restrained the thermal expansion of the specimen and prevented the loss of water, whereas applied steel sheet primarily reduced the loss of water during the fire test. Additionally, the fire exposed surface of one specimen of each mixture was pre-dried under controlled climate conditions and fire tested with applied steel rings. The results show a higher spalling volume for the ring restrained specimens compared to the other covering types. Further, the pre-dried boundary zone leads to delayed and decreased occurrence of spalling compared to the non-dried specimens for the concrete with quartzitic aggregates and to a prevention of spalling for the mixture with basalt aggregates. Additionally, the results show that the influence of the thermomechanical behaviour of the coarse aggregates increases with increasing restraint. The restrained conditions of the specimens with applied steel ring are comparable to the conditions in the centre of a large scale member. This test series is a further step for possible concept of steel ring restraint concrete specimens as “screening-tests” in upcoming projects. T2 - IWCS 2022 CY - Berlin, Germany DA - 12.10.2022 KW - Spalling KW - Fire test KW - Concrete KW - Restraint PY - 2022 SP - 15 EP - 24 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-56020 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Klimek, André T1 - Screening-tests on the susceptibility to spalling of two ordinary concretes N2 - Investigating the spalling behaviour of a concrete mixture using large scale members is complex and expensive. Thus, the susceptibility of concrete to spalling is investigated by means of fire tests on small scale specimens. However, the reduction of the fire exposed surface increases the influence of boundary effects. Macrocracking and the water loss via the lateral surfaces reduce the impact of the thermomechanical and thermohydraulic damage mechanisms and therefore, lower the risk of spalling. Thus, the influence of different restraints on the spalling behaviour of intermediate scaled specimens (Ø0.47 m; h=0.29 m) was investigated for two ordinary concrete mixtures. Both mixtures had the same composition except the type of aggregate. One mixture contained only quartzitic aggregates, whereas the other mixture was made with basalt grit as coarse aggregates. Applied steel rings restrained the thermal expansion of the specimen and prevented the loss of water, whereas applied steel sheet primarily reduced the loss of water during the fire test. Additionally, the fire exposed surface of one specimen of each mixture was pre-dried under controlled climate conditions and fire tested with applied steel rings. The results show a higher spalling volume for the ring restrained specimens compared to the other covering types. Further, the pre-dried boundary zone leads to delayed and decreased occurrence of spalling compared to the non-dried specimens for the concrete with quartzitic aggregates and to a prevention of spalling for the mixture with basalt aggregates. Additionally, the results show that the influence of the thermomechanical behaviour of the coarse aggregates increases with increasing restraint. The restrained conditions of the specimens with applied steel ring are comparable to the conditions in the centre of a large scale member. This test series is a further step for possible concept of steel ring restraint concrete specimens as “screening-tests” in upcoming projects. T2 - 7th International Workshop on Concrete Spalling due to Fire Exposure CY - Berlin, Germany DA - 12.10.2022 KW - Spalling KW - Fire test KW - Concrete KW - Restraint PY - 2022 AN - OPUS4-56023 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Tamsen, Erik T1 - Towards an automatic optimization framework for performance oriented precast concrete design N2 - The aim of the project LeBeDigital is to present opportunities of digitalization for concrete applications and show a way towards a performance oriented material design. Due to the high complexity of the manufacturing process of concrete and the range of parameters affecting the effective composite properties, a global optimization is challenging. Currently, most optimization is only carried out on a narrow scope related to the respective players, e.g. a mix optimization for a target strength, or a design optimization for minimum weight, using a given mix. To enable a path toward a full global optimization requires a reproducible chain of data, accessible for all contributors. We propose a framework based on an ontology, which automatically combines experimental data with numerical simulations. This not only simplifies experimental knowledge transfer, but allows the model calibration and the resulting simulation predictions to be reproducible and interpretable. In addition to an optimized set of parameters, this setup allows to study the quality and uncertainty of the data and models, as well as giving information about optimal experiments to improve the data set. We will present the proposed optimization workflow, using the example of a precast concrete element. The contribution will focus on the workflow and challenges of an interoperable FEM formulation. T2 - Material Science and Engineering, MSE Congress 2022 CY - Darmstadt, Germany DA - 27.09.2022 KW - Performance oriented concrete design KW - Ontology KW - Optimization workflow PY - 2022 AN - OPUS4-56208 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Eilers, M. A1 - Alte-Teigeler, R. A1 - Borchers, R. A1 - Gallai, G. A1 - Habiger, D. A1 - Recknagel, Christoph A1 - Karczewski, B. A1 - Koll, J. A1 - Lorenz, S. A1 - Marossow, H. A1 - Schneider, Th. A1 - Seiffart, J. A1 - Stark, S. A1 - et al., T1 - Technische Lieferbedingungen für die Baustoffe zur Herstellung von Fahrbahnübergängen aus Asphalt (TL ING, Teil 6, Abschnitt 7) N2 - TL BEL-FÜ Technische Lieferbedingungen für die Baustoffe zur Herstellung von Fahrbahnübergängen aus Asphalt TL/TP-Ing - Teil 6, Abschnitt 7 Technische Lieferbedingungen und Technische Prüfvorschriften für Ingenieurbauten KW - Brückenbeläge KW - Asphaltbauweisen KW - Fahrbahnübergänge PY - 2022 SN - 978-3-86446-342-6 VL - 780/2 SP - 1 EP - 20 PB - FGSV Verlag GmbH CY - Köln AN - OPUS4-56216 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hille, Falk T1 - Structural Health Monitoring am Großen Fallturm der BAM N2 - Am Fallturm auf dem Testgelände Technische Sicherheit (TTS) der BAM wurden bei Inspektionen Vorspannungsverluste in den Bolzen der Stahlverbindungen festgestellt. Um ein Verständnis für die zugrundeliegenden Trag- und Schädigungsmechanismen zu erlangen und um den Zustand der vorgespannten Schraubverbindungen langzeitlich zu überwachen, wurde am Fallturm ein Structural Health Monitoring (SHM) System installiert. Für die Auslegung des Monitoringsystems sowie zur Unterstützung der Untersuchung des Schädigungsprozesses wurde ein numerisches Modell erstellt und in Bezug auf die gemessenen Antworten des Tragwerks kalibriert. Im Vortrag werden die experimentellen und numerischen Untersuchungen zur Systemidentifikation des Stahlrohrgitterturms als auch die Überwachungskampagne mit dem eingesetzten Monitoringsystem sowie die Messergebnisse und deren Bewertung vorgestellt. T2 - Seminar "Zerstörungsfreie Prüfung" am Lehrstuhl für Zerstörungsfreie Prüfung ,Technische Universität München CY - Online meeting DA - 13.01.2022 KW - Structural Health Monitoring KW - Schadensüberwachung KW - Schwingungsmonitoring PY - 2022 AN - OPUS4-56667 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Jafari, Abbas A1 - Titscher, Thomas A1 - Chatzi, E. A1 - Unger, Jörg F. T1 - Variational Bayesian inference of damage in concrete material using spatially-dense data N2 - Numerical simulators, such as finite element models, have become increasingly capable of predicting the behaviour of structures and components owing to more sophisticated underlying mathematical models and advanced computing power. A common challenge lies, however, in calibrating these models in terms of their unknown/uncertain parameters. When measurements exist, this can be achieved by comparing the model response against measured data. Besides uncertain model parameters, phenomena like damage can give rise to further uncertainties; in particular, quasi-brittle materials, like concrete, experience damage in a heterogeneous manner due to various imperfections, e.g. in geometry and boundary conditions. This hardens an accurate prediction of the damaged behaviour of real structures that comprise such materials. In this study, which draws from a data-driven approach, we use the force-version of the finite element model updating method (FEMU-F) to incorporate measured displacements into the identification of the damage parameters, in order to cope with heterogeneity. In this method, instead of conducting a forward evaluation of the model and comparing the model response (displacements) against the data, we impose displacements to the model and compare the resulting force residuals with measured reaction forces. To account for uncertainties in the measurement of displacements, we endow this approach with a penalty term, which reflects the discrepancy between measured and imposed displacements, where the latter is assumed as unknown random variables to be identified as well. A Variational Bayesian approach is used as an approximating tool for computing posterior parameters. The underlying damage model considered in this work is a gradient-enhanced damage model. We first establish the identification procedure through two virtual examples, where synthetic data (displacements) are generated over a certain spatially-dense set of points over the domain. The procedure is then validated on an experimental case-study; namely a 3-point bending experiment with displacement measurements resulting from a digital image correlation (DIC) analysis. T2 - MSE 2022 CY - Online meeting DA - 27.09.2022 KW - Heterogeneity KW - Gradient damage KW - Model updating KW - Variational Bayesian KW - Concrete PY - 2022 AN - OPUS4-56625 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Fürst, Richard A1 - Häßler, Dustin A1 - Stelzner, Ludwig A1 - Hothan, Sascha T1 - In situ test procedure to determine the fire resistance of exisiting steel structures with aged intumescent coating N2 - Intumescent coatings are commonly used in civil engineering to increase the fire resistance of steel structures. In case of a fire, the intumescent coating reacts and forms a thermally protective char around the steel member. Thus, the heating of the steel is significantly delayed, and as a result, a higher fire resistance can be achieved. Throughout the working life, intumescent coatings are aged by climatic factors. To predict durability for several years, the behaviour of the intumescent coatings is extrapolated based on accelerated artificial ageing. The established German and European assessment procedures to test and predict durability assume a working life of at least 10 years. For an extended period, additional evidence is required; yet the procedure and specifications to justify this are not described. Available in situ methods to assess the thermal performance of intumescent coatings are currently limited in their information content. Therefore, BAM is conducting a research project to develop a minimally invasive in situ test procedure to determine the fire resistance of existing steel structures with applied intumescent coating. The paper will describe the test setup, the developed prototype furnace, and the results of the performed test programme with uncoated and coated steel specimens. Based on this, recommendations for the test procedure are given. T2 - Structures in Fire 2024 CY - Coimbra, Portugal DA - 19.06.2024 KW - In situ KW - Intumescent coating KW - Steel structures KW - Test procedure PY - 2024 SN - 978-989-35292-2-5 DO - https://doi.org/10.30779/cmm_SIF24 SP - 1217 EP - 1228 AN - OPUS4-61258 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Fürst, Richard A1 - Häßler, Dustin A1 - Stelzner, Ludwig A1 - Hothan, Sascha T1 - Development of an in situ test method to assess the fire resistance of steel members with applied intumescent coating N2 - Intumescent coatings are commonly used in civil engineering to improve the fire resistance of steel constructions. Exposed to fire, the intumescent coating reacts and forms a thermal protective char around the steel member. Thus, the heating of the steel is delayed, and a higher fire resistance can be achieved. Generally, the scope of application and the durability of intumescent coatings are described in national approvals or European Technical Assessment (ETA) documents. Due to environmental conditions, intumescent coatings are subjected to ageing effects, which can reduce their durability and thermal protection performance. Available in situ methods to investigate the performance of applied intumescent coatings, such as visual inspection, flame exposure testing, adhesive tensile tests or chemical analysis, are not fully conclusive. Therefore, in the civil engineering practice, there is an increasing demand to verify the fire resistance of existing steel structures with applied intumescent coatings necessary in several cases, e.g., the working life is exceeded, the visual appearance of the intumescent coating changed or the information about the applied product is missing. The research presented in the paper shows the progress of the ongoing research project "INSIST" at BAM, where a new in situ method is being developed to assess the actual fire resistance of existing steel structures with applied intumescent coating. The investigation is based on a development of the in situ test procedure and a mobile prototype furnace. T2 - 10th Symposium Structural Fire Engineering – TU Braunschweig 2024 CY - Braunschweig, Germany DA - 24.09.2024 KW - In situ KW - Intumescent coating KW - Steel structures KW - Test procedure PY - 2024 AN - OPUS4-61261 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ramasetti, Eshwar Kumar A1 - Herrmann, Ralf A1 - Degener, Sebastian A1 - Baeßler, Matthias T1 - Development of generic AI models to predict the movement of vehicles on bridges N2 - For civil, mechanical, and aerospace structures to extend operation times and to remain in service, structural health monitoring (SHM) is vital. SHM is a method to examining and monitoring the dynamic behavior of essential constructions. Because of its versatility in detecting unfavorable structural changes and enhancing structural dependability and life cycle management, it has been extensively used in many engineering domains, especially in civil bridges. Due to the recent technical developments in sensors, high-speed internet, and cloud computing, data-driven approaches to structural health monitoring are gaining appeal. Since artificial intelligence (AI), especially in SHM, was introduced into civil engineering, these modern and promising methods have attracted significant research attention. In this work, a large dataset of acceleration time series using digital sensors was collected by installing a structural health monitoring (SHM) system on Nibelungen Bridge located in Worms, Germany. In this paper, a deep learning model is developed for accurate classification of different types of vehicle movement on the bridge from the data obtained from accelerometers. The neural network is trained with key features extracted from the acceleration dataset and classification accuracy of 98 % was achieved. T2 - SMAR 2024 - 7th International Conference on Smart Monitoring, Assessment and Rehabilitation of Civil Structures CY - Salerno, Italy DA - 04.09.2024 KW - Machine learning KW - Structural Health Monitoring (SHM) PY - 2024 AN - OPUS4-61375 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Herrmann, Ralf T1 - A Living Lab for Structural Health Monitoring at the Nibelungen Bridge Worms for Transfer Learning of Structural Dynamics N2 - The Nibelungen Bridge in Worms, Germany has been selected as a national demonstration structure for advanced non-destructive testing (NDT) and structural health monitoring concepts to extend the lifetime of civil structures and to optimize O&M actions. Parts of the research that involves this bridge as a demonstrator belong to the focus area program SPP100+. In this program, the bridges SHM System has been extended and combined with an additional setup of vibration sensors. The used digital smart sensor with pre-processing functions, the arrangement of the sensors at the structure and additional edge computing capability allows the investigation of transfer learning and other methods directly into the real structure. The living lab with seven triaxial accelerometers can be reconfigured in real-time and adjusted to the needs of AI models for classification. The comparison with the existing conventional SHM sensors has been made possible by hardware synchronization to the existing SHM System and collocating sensors at similar positions, so that a hardware exchange can be an investigated use-case for the transfer learning. During idle times, the system collects vibration data like a conventional SHM system. T2 - 10th European Workshop on Structural Health Monitoring (EWSHM 2024) CY - Potsdam, Germany DA - 10.06.2024 KW - Structural Health Monitoring (SHM) KW - SPP100+ KW - Nibelungen Bridge KW - Sensor technology PY - 2024 AN - OPUS4-61284 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Fürst, Richard A1 - Häßler, Dustin A1 - Stelzner, Ludwig A1 - Hothan, Sascha T1 - In situ test procedure to determine the fire resistance of existing steel structures with aged intumescent coating N2 - BAM is conducting a research project to develop a minimally invasive in situ test procedure to determine the fire resistance of existing steel structures with applied intumescent coating. In presentation and submitted paper is describe the test setup, the developed prototype furnace, and the results of the performed test programme with uncoated and coated steel specimens. Based on this, recommendations for the test procedure are given. T2 - Structures in Fire 2024 CY - Coimbra, Portugal DA - 19.06.2024 KW - In situ KW - Intumescent coating KW - Steel structures KW - Test procedure PY - 2024 AN - OPUS4-61257 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hille, Falk T1 - Leitfaden für den strategischen Einsatz von Monitoring an Straßenbrücken N2 - Für die Anwendung von Structural Health Monitoring (SHM) im Rahmen des Managements von Straßenbrücken wurde zur Unterstützung von Straßenbauverwaltungen, Ingenieurbüros, Bauunternehmen und weiteren Akteuren die Erstellung eines Leitfadens initiiert. Dieser Leitfaden stellt typische Anwendungsfälle für Monitoring vor und schlägt für diese bewährte Herangehensweisen vor. Darüber hinaus bietet der Leitfaden Empfehlungen für Ausschreibung und Vergabe von Monitoringleistungen, eine Anleitung zur Bewertung des wirtschaftlichen Nutzens von SHM, Hinweise zur optimal einsetzbaren Messtechnik sowie einen Ansatz für das Datenmanagement zur Integration der Monitoringdaten in das Brückenmanagement. T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM CY - Berlin, Germany DA - 16.10.2024 KW - Bauwerksmonitoring KW - Straßenbrücken KW - Leitfaden PY - 2024 AN - OPUS4-61400 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Strangfeld, Christoph T1 - In situ Prozessüberwachung und Qualitätskontrolle bei der additiven Fertigung von Betonbauteilen N2 - In der additiven Fertigung von Beton wird kontinuierlich Material gemischt und verarbeitet. Dies erfordert eine kontinuierliche in situ Prozessüberwachung und Qualitätskontrolle. An der BAM wurde ein 3D-Betondrucker aufgebaut, der eine umfängliche Prozessüberwachung ermöglicht. Druck-, Temperatur- und Feuchtesensoren in der Pumpe und im Fördersystem erlauben ein kontinuierliches Monitoring des Frischbetons, während ein Laserlinienscanner am Druckkopf unmittelbar die gedruckte Ist-Kontur verfolgt. Die so gewonnenen Daten können Grundlage für die Erarbeitung von Normen für die additive Fertigung von Betonbauteilen sein und somit deren Standsicherheit gewährleisten. T2 - 63. For‍schungs‍kol‍lo‍qui‍um des Deutschen Ausschuss für Stahlbeton CY - Berlin, Germany DA - 16.10.2024 KW - Additive Fertigung KW - Beton KW - Frischbetoncharakterisierung KW - Extrusionsdruck PY - 2024 AN - OPUS4-61390 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Jeyifous, Olubunmi Anthony A1 - Schönsee, Eric A1 - Strangfeld, Christoph A1 - Hüsken, Götz T1 - Correlation of continuously measured in-line process parameters and extruded geometry in 3D concrete printing experiments N2 - Additive manufacturing of concrete structures is a novel and emerging tech-nology. Free contouring in civil engineering, which allows for entirely new designs, is a significant advantage. Although several techniques and ap-proaches demonstrate these advantages, quality control during printing is highly challenging and rarely applied. Due to the continuous mixing process used in 3D concrete printing, it is impossible to exclude variations in the dry mixture or water content, and a single test sample is insufficient to represent the whole structure. A defect in one layer during printing can affect the in-tegrity of the entire structure. Therefore, continuous and real-time process monitoring is required to record and document the printing process. At the Bundesanstalt für Materialforschung und -prüfung (BAM), a test rig for 3D concrete printing was developed to monitor the properties during the printing process. This study investigates the relationship between geometric accuracy and process parameters (pressure, pump torque, print speed, layer height, water content) in extrusion-based 3D concrete printing. Using a high-precision laser scanner, the geometric measurements of printed concrete ele-ments are evaluated in real-time. The concrete elements are printed under controlled conditions with varied process parameters. Preliminary findings indicate a significant correlation between process variables and geometric ac-curacy. T2 - Fourth RILEM International Conference on Concrete and Digital Fabrication CY - Munich, Germany DA - 04.09.2024 KW - 3D concrete printing KW - Geometric accuracy KW - Process monitoring KW - Quality control PY - 2024 DO - https://doi.org/10.1007/978-3-031-70031-6_15 SP - 127 EP - 133 AN - OPUS4-61534 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hüsken, Götz T1 - Wiederholbarkeit additiv gedruckter Betonbauteile N2 - Die additive Fertigung von Betonbauteilen, auch bekannt als 3D-Betondruck, ist eine Technologie, die im letzten Jahrzehnt aufgrund ihrer finanziellen und ökologischen Vorteile als nachhaltige Fertigungstechnologie viel Aufmerksamkeit erhalten hat. Obwohl die Vorteile der additiven Fertigung bereits durch zahlreiche Forschungs- und Demonstrationsprojekte gezeigt wurden, ist die Qualitätskontrolle während des Druckens äußerst anspruchsvoll und wird auch aufgrund fehlender harmonisierter Normen kaum angewendet. Aufgrund des kontinuierlichen Mischprozesses beim 3D-Betondruck ist es unmöglich Schwankungen des Trockenmörtels oder des Wassergehalts auszuschließen. Daher ist eine einzelne Stichprobe nicht mehr repräsentativ für das gesamte Bauteil und ein während des Druckens in einer Schicht auftretender Fehler kann die Integrität der gesamten Struktur beeinträchtigen. In diesem Beitrag werden die Ergebnisse eines als Fachwerkstruktur konzipierten Bogens, der unter vergleichbaren Randbedingungen mehrmals mit einem 3D-Betonextrusionsdrucker gedruckt wurde, vorgestellt. Jeder Bogen wurde auf seine mechanische Festigkeit und sein Tragverhalten geprüft. Die Ergebnisse der mechanischen Prüfungen der gedruckten Bögen werden mit Materialdaten aus klassischen Materialprüfungen verglichen und hinsichtlich ihrer statistischen Signifikanz diskutiert. T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM Green Intelligent Building CY - Berlin, Germany DA - 16.10.2024 KW - Additiv gedruckte Betonbauteile KW - Wiederholbarkeit KW - Monitoring KW - 3D-Betondruck PY - 2024 AN - OPUS4-61569 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Häßler, Dustin T1 - Forschungsprojekt "INSIST" in situ Bewertungsverfahren für reaktive Brandschutzsysteme (RBS) N2 - Projektvorstellung zum Arbeitsstand der Entwicklung des in situ Prüfverfahrens für Stahlbauteilen mit gealtertem reaktiven Brandschutzsystem. T2 - 110. Sitzung des Arbeitsausschusses „Brandschutz“ CY - Braunschweig, Germany DA - 05.11.2024 KW - Feuerwiderstand KW - Branversuch KW - Reaktives Brandschutzsystem KW - Stahl PY - 2024 AN - OPUS4-61521 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Jeyifous, Olubunmi Anthony T1 - Correlation of continuously measured in-line process parameters and extruded geometry in 3D concrete printing experiments N2 - Additive manufacturing of concrete structures is a novel and emerging tech-nology. Free contouring in civil engineering, which allows for entirely new designs, is a significant advantage. Although several techniques and ap-proaches demonstrate these advantages, quality control during printing is highly challenging and rarely applied. Due to the continuous mixing process used in 3D concrete printing, it is impossible to exclude variations in the dry mixture or water content, and a single test sample is insufficient to represent the whole structure. A defect in one layer during printing can affect the in-tegrity of the entire structure. Therefore, continuous and real-time process monitoring is required to record and document the printing process. At the Bundesanstalt für Materialforschung und -prüfung (BAM), a test rig for 3D concrete printing was developed to monitor the properties during the printing process. This study investigates the relationship between geometric accuracy and process parameters. T2 - Fourth RILEM International Conference on Concrete and Digital Fabrication CY - Munich, Germany DA - 04.09.2024 KW - 3D concrete printing KW - Geometric accuracy KW - Process monitoring KW - Quality control PY - 2024 AN - OPUS4-61535 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Recknagel, Christoph T1 - Innovatives Messsystem - SensoJoint N2 - Permanent erfolgen konstruktive Verbesserungen der Bauwerke, stoffliche Weiterentwicklungen der Baustoffsysteme sowie technologische Optimierungen der Bauprozesse. Damit einhergehende Veränderungen, z.B. im Reaktionsverhalten der Betonfahrbahndecke unter äußeren Beanspruchungen, kumulieren in sensiblen Bereichen wie z.B. den Fugenbereichen. Der Posterbeitrag „Innovatives Messsystem -Sensojoint" stellt ein Messsystem vor, dass entsprechend den Anforderungen der Straßenbaupraxis Deformationen/Formänderungen von Bauteilen der Verkehrsinfrastruktur in 3 Richtungsachsen erfassen kann. Die hoch auflösende Sensorik wurde speziell für eine Anwendung direkt in der Rollspur des Schwerverkehrs von hochbeanspruchten Betonfahrbahndecken ausgelegt, so dass nicht nur klimatisch induzierte Deformationen sondern auch verkehrsinduzierte relative Fugenbewegungen erfasst werden können. Für das Projekt „SensojointField" wurde für den Sensoreinsatz eine komplette Messstation zur Untersuchung der Fugenbewegungen in hochbeanspruchten Betonfahrbahnen entwickelt, die für lang andauernde Messkampagnen im Feld konfiguriert wurde. T2 - Jubiläumskongress 100 Jahre Deutscher Straßen- und Verkehrskongress CY - Bonn, Germany DA - 23.10.2024 KW - Infrastruktur KW - Innovative Untersuchungsmethodik KW - Performance-concept PY - 2024 AN - OPUS4-61541 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Herrmann, Ralf T1 - Föderiertes Datenmanagement von Monitoringdaten aus Structural Health Monitoring Anwendungen und daraus gewonnenen Trainingsdaten bei Spannbetonbrücken N2 - Beim Structural Health Monitoring entstehen eine Vielzahl von Daten, Metadaten und Modellen mit hohem Wert für die Beurteilung des Bauwerkszustands und der Prognose von Veränderungen. Kontinuierlich anwachsende Datenbestände müssen nachhaltig geteilt, genutzt und über die Bauwerkslebensdauer archiviert werden. Dabei stellen die Vielfalt der Messaufgaben, die Heterogenität der Daten, die dezentrale Erfassung und z. T. der Umfang eine Herausforderung für die beteiligten Akteure dar. Für den Datentransfer der Monitoringdaten zwischen der Straßenbauverwaltung und den Monitoringausführenden wird ein flexibles Abstimmungsverfahren vorgeschlagen und ein Lösungskonzept für ein föderiertes Datenmanagement skizziert. Eine weitere Herausforderung stellt die bauwerksübergreifende Zusammenstellung von Trainingsdaten für konkrete KI-Anwendungen dar. T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM Green Intelligent Building CY - Berlin, Germany DA - 16.10.2024 KW - Structural Health Monitoring KW - Spannbetonbrücke KW - Datenmanagement KW - Auftraggeber-Daten-Anforderungen (ADA) KW - Bauwerkschäden PY - 2024 AN - OPUS4-61780 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Unger, Jörg F. T1 - FAIR principles and benchmarking of research (simulation) software as essential data N2 - Software is an integral part of research data. The RDA working group 'FAIR for Research Software (FAIR4RS)' has extended the FAIR principles, particularly tailored to research software [1]. The challenge of integrating these general principles into software for numerically solving physics based model is solved by each community and often even each individual researcher with a different approach. A particular challenge of research software in the simulation domain is its complex dependencies because it is usually built upon many other software contributions. Another challenge for a FAIR implementation is the integration of these modules into simulation workflows that define a sequential order for the execution of individual simulations tasks usually described by a graph, as well as the compute environment. In NFDI4Ing, a comparison of selected workflow tools has been performed [2]. When making research software FAIR, all these levels (individual module, simulation workflow, result of a specific run of the workflow) are to be considered. Several approaches such as RO-Crate with an extension Workflow Run Crate [3], the Citation File Format [https://citation-file-format.github.io/], the common workflow language with CWLProv for describing workflow provenance [4], and many more are currently being developed. In NFDI4ING, there are related activities such as a search engine to find research software matching certain attributes [5]. The goal of a working group on the BaseNFDI level would be to establish standards on how FAIR simulation workflows can be developed and shared within the communities, related to both the workflows as well as the results of an individual run. Another requirement is the interoperability with domain-relevant community standards for data exchange. Even though ongoing efforts in our community aim to build standardized file formats, e.g., the VMAP standard for Finite Element Models, implementations are often slightly different, making it a challenge to exchange one interoperable software tool with another one while being able to reproduce the results. From our perspective, benchmarking of tools with well-defined test data is thus mandatory, but a general platform for this purpose is missing. This includes e.g. building an editorial board of experts for defining benchmarks, a platform for hosting codes with appropriate administrative structures to ensure code quality, a tool independent and machine-readable description of benchmark problems, an execution platform for running the benchmarks and tools and resources (e.g. a jupyterhub) to publish/visualize and explore the results within the community. For this purpose, a tool for comparing field data [6] has been developed, and a platform for integrating benchmark tests is planned to be developed. Those challenges are not specific to the engineering domain, and as such, we hope to establish a working group in the base community to build a software benchmarking framework for simulation software to address these challenges in a cross-disciplinary manner. T2 - 1st Base4NFDI User Conference (UC4B2024) CY - Berlin, Germany DA - 20.11.2024 KW - Workflows KW - Research software KW - Benchmarking PY - 2024 AN - OPUS4-61768 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Telong, Melissa T1 - Beton-Datenmanagement anhand von wissensbasierten Datenstrukturen unter Nutzung von Ontologien und Wissensgraphen N2 - Im Rahmen der Entwicklung von Betonrezepturen,bei der Betonherstellung und während derNutzungsphase im Bauwerk, wird eine Vielzahl vonMaterialdaten generiert. LeBeDigital (Lebenszyklusvon Beton - Ontologie-Entwicklung für dieProzesskette der Betonherstellung) ist einVerbundprojekt innerhalb der Initiative PlattformMaterial Digital. Das Projekt zielt darauf ab, eineStruktur für Betonmaterialdatenbanken zuentwickeln, die dem FAIR-Prinzip folgt und sowohlpraxisnah als auch flexibel genug ist, um zukünftigeEntwicklungen in der Betonforschung und -produktion zu unterstützen. Ontologien stellen eingeeignetes Werkzeug zur Generie-rung vonWissensgraphen dar, um Workflows zur automatisierten Datenerfassung und zursemantischen Da-tenabfrage zu gestalten. Daher istdie Erarbeitung betonspezifischer Ontologienzentraler Bestandteil des Ver-bundprojektes, dasdazu beitragen will, die Vorrausetzungen für eineTeilhabe der Betonbranche am digitalen Wandel imBereich der Materialforschung zu sichern. T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM Green Intelligent Building CY - Berlin, Germany DA - 16.10.2024 KW - Ontologie KW - Betonherstellung KW - Wissensgraph KW - Datenverwaltung PY - 2024 AN - OPUS4-61572 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hering, Marcus T1 - Impaktversuche an Stahlbetonplatten N2 - Seit 1977 ist der Flugzeugabsturz ein wesentliches Belastungsszenario bei der Auslegung von Kernkraftwerken. Zur Untersuchung dieses Szenarios wurden umfassende Studien durchgeführt, welche die Reaktion von Stahlbetonkonstruktionen unter Stoßbelastung analysieren. Da großmaßstäbliche Experimente teuer und aufwendig sind, gewinnen skalierte Versuche zunehmend an Bedeutung. Im Rahmen eines Forschungsprojekts der TU Dresden und der BAM wurden Grundlagen für skalierte Impaktversuche im großen Maßstab geschaffen, um die Übertragbarkeit vom Labor- auf Realmaßstab zu ermöglichen. T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM Green Intelligent Building CY - Berlin, Germany DA - 16.10.2024 KW - Stahlbetonplatten KW - Impaktversuch KW - Sicherheit Kernkraftwerke PY - 2024 AN - OPUS4-61770 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Thiele, Marc T1 - Monitoring an Türmen von Onshore Windenergieanlagen in Betonbauweise im Hinblick auf Ermüdung N2 - Der Beitrag stellt das Messkonzept sowie dessen Umsetzung für ein umfassendes Monitoringsystem an einer onshore Windenergieanlage mit einem Hybridturm vor. Dieses ist Bestandteil des Forschungsvorhabens Win-ConFat–Structure, welches neben der Validierung geeigneter Sensorik auch die Bewertung des Zustands und der möglichen Restlebensdauer der ermüdungsbeanspruchten Betonstruktur zum Ziel hat. Neben dem Monitoringsystem werden erste Messergebnisse aus den Betriebsdaten sowie vom Verhalten der Turmstruktur vorgestellt. T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM Green Intelligent Building CY - Berlin, Germany DA - 16.10.2024 KW - Onshore Windenergieanlagen KW - Ermüdung KW - Lebensdauerbewertung KW - Monitoring KW - WinConFat PY - 2024 AN - OPUS4-61773 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Simon, Patrick T1 - Temperatureinfluss auf Strukturmonitoring – aktuelle Versuche N2 - Strukturmonitoring kann wertvolle Daten für die Zustandsbewertung und Schadensdetektion von Infrastruk-turbauwerken liefern. Umgebungsbedingungen wie die Temperatur beeinflussen die Bauwerke und somit die Messdaten jedoch erheblich. Um Methoden für den Umgang mit Temperatureinflüssen zu entwickeln, wurden an der BAM Versuche an Stahlbeton- und Asphaltbalken unter kontrollierten Temperaturen von -40 °C bis 60 °C und definierten Schädigungen durchgeführt. Die Daten ermöglichen die Erforschung und Validierung neuer, auch unter Temperatureinfluss zuverlässiger Methoden des Strukturmonitorings. T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM Green Intelligent Building CY - Berlin, Germany DA - 16.10.2024 KW - Structural Health Monitoring KW - Strukturmonitoring KW - Temperatureinfluss KW - Klimakammer KW - Bayesian Updating PY - 2024 AN - OPUS4-61573 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hering, Marcus A1 - Fiedler, Georg T1 - Investigation of multiple impact-damaged reinforced concrete structures as a reference for liquid penetration behavior and tomographic studies N2 - The structural integrity of outer reinforced concrete (RC) containments of nuclear power plants provides an essential shield against external hazards. If this containment is damaged by an impact event, such as an aircraft crash, the question arises to which degree the reinforced concrete containment still has its protective capability. This concerns both purely structural protection and protection against liquids penetrating the interior of the containment. Due to the dimensions of the containment structures, it is difficult to perform real scale impact experiments, so in the past decades plate geometries at medium scale have been used for investigations. Detailed investigations on the structural behaviour of RC members or RC plates subjected to impact loading have already been presented in Just et al., Hering, Hering et al., Bracklow et al., Hille et al. and Nerger et al. The following investigations deal with the single and multiple impact event (first hard impact and/or subsequent soft impact) on a RC specimen, which provides the basis for further investigations. A description of the test setup and the test procedure as well as a presentation of the test results from the impact tests are provided. Furthermore, the experimental program is presented, which the damaged RC specimens are to undergo to deal with the question of how much the impact-damaged RC structure has become permeable to liquid media, such as water and kerosene, depending on the intensity of the impact. The aim of these following investigations is to develop a test setup that can be applied to investigate the liquid penetration behaviour (LPB) of small, medium, and large-scale RC members. In addition to the liquid penetration experiments, the damaged specimens are to be examined by planar tomography to obtain the damage inside the specimen. The combination of damaging event, fluid penetration behaviour and tomography should enable a comprehensive understanding of the damage to the RC specimen. T2 - Conference: 27th International Conference on Structural Mechanics in Reactor Technology (SMiRT) CY - Yokohama, Japan DA - 04.03.2024 KW - Drop Tower KW - Hard Impact KW - Multiple Impact KW - Soft Impact PY - 2024 AN - OPUS4-61991 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Cook, Jake A1 - von Werder, Julia T1 - Bioreceptive Concrete Surfaces: Understanding Material-Biology Interactions for Façade Greening N2 - The climate crisis has led to a growing demand for environmentally oriented approaches in the construction industry, including not only eco-friendly materials, but also the greening of urban spaces. Microbial facade greening with algae is a novel concept based on the inherent bioreceptive properties of different building materials. This study focuses on the influence of physical material properties on biofilm formation. Differently textured samples from the same UHPC mix were produced and their roughness and water absorption documented. The samples were then weathered under laboratory conditions to observe material-algae interactions. T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM Green Intelligent Building CY - Berlin, Germany DA - 16.10.2024 KW - Bioreceptive concrete surface KW - Facede Greening KW - Adhesion strength experiment PY - 2024 AN - OPUS4-61811 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Unger, Jörg F. T1 - Von Messdaten zum optimierten Bauteil durch Kombination von Material- und Strukturdesign N2 - Die Entwicklung eines optimierten Designs für Bauwerke erfordert die Berücksichtigung sowohl des Materials als auch des Strukturdesigns. Ziel des Beitrages ist die Vorstellung eines Designprinzips basierend auf automatisierten Workflows, das am Beispiel eines Biegebalkendesign zur Reduzierung des Treibhauspotenzials vorgestellt wird. Eine ganzheitliche Optimierung berücksichtigt Material- und Strukturdesign. Es werden physikalische Modelle mit Ansätzen aus dem maschinellen Lernen kombiniert, die mit experimentellen Daten kalibriert bzw. trainiert werden. Eine besondere Bedeutung hat dabei die Berücksichtigung von Unsicherheiten. T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM Green Intelligent Building CY - Berlin, Germany DA - 16.10.2024 KW - Optimiertes Design für Bauwerke KW - Strukturdesign KW - Biegebalkendesign KW - Betonbau PY - 2024 AN - OPUS4-61790 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schneider, Ronald T1 - Kontinuierliche sensordaten- und modellgestützte Bewertung von Infrastrukturbauwerken in der Praxis N2 - Ein Einsatz von kontinuierlichen sensorbasierten Verfahren komplementär zu den zeitlich diskreten bildbasierten Verfahren haben ein enormes Potenzial, die bisher hauptsächlich visuellen Prüfprozesse zu transformieren. Zur Ermöglichung eines strategischen Einsatzes des sensorbasierten Monitorings im Erhaltungsmanagement von Ingenieurbauwerken ist das übergeordnete Ziel des Projektes AISTEC-Pro die Demonstration des praktischen Mehrwerts des sensorbasierten Monitorings. Dies wird durch praktische Anwendungen an der Maintalbrücke Gemünden und einem neu ausgewählten Referenzbauwerk unter Berücksichtigung von typischen Einsatzszenarien im Bereich der Bauwerkserhaltung erreicht werden. Die Einsatzszenarien werden in enger Abstimmung mit den Endanwendern entwickelt und fortgeschrieben. Hierbei wird insbesondere Bezug auf die aktuelle Neufassung der DIN 1076 genommen, in der erstmals die Anwendung von sensor- und bildbasierten Monitoringverfahren in der Bauwerksprüfung geregelt wird. T2 - AISTEC-Pro Auftakttreffen CY - Weimar, Germany DA - 02.12.2024 KW - Sensorbasiertes Monitoring KW - Erhaltung KW - Verkehrsbrücken PY - 2024 AN - OPUS4-61919 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kobe, André A1 - Stelzner, Ludwig A1 - Hothan, Sascha A1 - Zehfuß, Jochen T1 - Der Einfluss der Prüfbedingungen auf das Abplatzverhalten von Beton im Brandfall T1 - The influence of the test conditions on the spalling behaviour of concrete due to fire exposure N2 - Die Durchführung von realmaßstäblichen Bauteilversuchen zur Analyse des Abplatzverhaltens von Beton im Brandfall ist aufwendig, material‐ und kostenintensiv und setzt die Verfügbarkeit von Großbrandversuchsständen voraus. Daher wird die Abplatzneigung von Beton vorwiegend an kleinformatigen Prüfkörpern untersucht. Mit der Reduktion der Prüfkörpergröße verringert sich der thermische und hygrische Gradient im Randbereich, wodurch sowohl die thermisch induzierten Schädigungen im Beton als auch die Abplatzungen verringert werden. Für ein besseres Verständnis dieser komplexen Zusammenhänge wurde das Abplatzverhalten kleinformatiger Betonprüfkörper (Ø = 0,47 m; h = 0,29 m) mit verschiedenartigen Ummantelungen und unterschiedlichen Feuchtezuständen der Betonrandzone für zwei Normalbetone analysiert. Am Prüfkörper applizierte Stahlringe behinderten dabei die thermische Ausdehnung sowie den Wasserverlust über die Mantelfläche. Die Ergebnisse zeigen, dass die Abplatzungen infolge der Prüfkörperummantelung zunehmen und die Größenordnung vergleichender Großbrandversuche erreichen. Dies lässt den Schluss zu, dass die Ummantelung eines kleinformatigen Prüfkörpers mit Stahlring die Prüfbedingungen in der Mitte der brandbeanspruchten Fläche eines großformatigen Bauteils nachstellen kann. Des Weiteren führt die Vortrocknung der Betonrandzone zur Verzögerung bzw. Verringerung von Abplatzungen. N2 - Investigating the spalling behaviour of a concrete mixture using large scale members is complex and expensive. Thus, the susceptibility to spalling of concrete is investigated by means of fire tests on small format specimens. However, the reduction of the fire exposed surface increases the influence of boundary effects. Macrocracking and the water loss via the lateral surfaces reduce the thermomechanical and thermohydraulic damage and therefore, lower the risk of spalling. Thus, this study investigated the influence of different restraint and moisture conditions on the spalling behaviour of small format specimens (Ø = 0.47m; h = 0.29m) for two ordinary concrete mixtures. Applied steel rings restrained the thermal expansion of the specimen and prevented the water loss during the fire test. The results show that increased spalling occurred to a similar extend as in large scale fire tests because of a restrained expansion of the specimen. Further, a pre-dried boundary zone led to a delayed or rather a prevention of spalling compared to the non-dried specimens. To determine the susceptibility to spalling of a concrete mixture, the test conditions in the centre of a large scale member can be simulated by restraining the expansion of a small format specimen with applied steel rings. KW - Beton KW - Brand KW - Abplatzen KW - Zwang PY - 2025 DO - https://doi.org/10.1002/best.202400104 SN - 1437-1006 SP - 1 EP - 10 PB - Wiley AN - OPUS4-62732 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - von Werder, Julia T1 - Biorezeptivität statt Biozide: Herausforderungen und Chancen von Biofilmfassaden N2 - Der Vortrag beschreibt die Herausforderungen bei der Konzeption biorezeptiver Betonfassaden. Es werden sowohl aktuelle Forschungsergebnisse zu einem geeigneten Materialdesign erläutert als auch die Anforderungen an die Prüfung der Biorezeptivität, die zu berücksichtigen sind. T2 - Monitoring und Simulation zur Fassadenbewertung CY - Coburg, Germany DA - 15.04.2024 KW - Begrünung KW - Biorezeptivität KW - Beton KW - Biofilm KW - Biozide PY - 2024 AN - OPUS4-62227 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - von Werder, Julia T1 - Gebäudebegrünung mit Biofilmen: Herausforderungen und Chancen N2 - Der Vortrag stellt die Ergebnisse der Forschungsarbeiten zur Biorezeptivität von Betonfassaden sowie der gezielten Applikation von Algen dominierten Biofilmen auf Betonfassaden vor. Insbesondere werden die Anforderungen an eine repräsentative Prüfmethode erläutert. T2 - BuGG-Tag der Forschung und Lehre Gebäudegrün 2024 CY - Leipzig, Germany DA - 26.09.2024 KW - Begrünung KW - Biorezeptivität KW - Beton KW - Biofilm PY - 2024 AN - OPUS4-62221 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hicke, Konstantin T1 - Measuring Dynamic Behavior and Damage Evolution of a Reinforced Concrete Wall Subjected to Explosive Blasts using Embedded Distributed Fiber Optic Sensors N2 - Results from highly dynamic and static strain measurements, respectively, using embedded distributed fiber optic sensors in a steel-reinforced concrete wall under explosive blast-loading are presented, detailing the structure’s dynamic behavior and the evolutions of cracks. T2 - 28th International Conference on Optical Fiber Sensors (OFS-28) CY - Hamamatsu, Japan DA - 20.11.2023 KW - Distributed acoustic sensing KW - DAS KW - Structural response KW - Blast experiment KW - Embedded fiber optic sensor PY - 2023 AN - OPUS4-59094 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Recknagel, Christoph A1 - Spilker, Alexandra A1 - Buchheim, Janine T1 - INFUKON - Ein neuer Ansatz zur ganzheitlichen Analyse des Gebrauchsverhaltens hochbeanspruchter Betonfahrbahndecken im Fugenbereich N2 - Betonfahrbahndecken zeichnen sich insbesondere durch eine hohe Dauerhaftigkeit und Wartungsarmut aus, welche im Ergebnis zu einer sehr guten Kosteneffizienz und Nachhaltigkeit führen. In den vergangenen Jahren wurden große Fortschritte hinsichtlich der Weiterentwicklung von Konstruktion, Baustoff und Fahrbahnoberfläche erzielt. Forschung und Entwicklung befassen sich seit einigen Jahren systematisch auch mit der Optimierung von Fugensystemen für hochbeanspruchte Bundesfernstraßen. Das Forschungsprojekt INFUKON liefert einen generalisierbaren methodischen Ansatz zur ganzheitlichen Analyse des Gebrauchsverhaltens hochbeanspruchter Fugensysteme in Betonfahrbahndecken und eine innovative Versuchseinrichtung die als technische Grundlage zur Verfügung stehen. In diesem Beitrag werden wesentliche Projektergebnisse vorgestellt. KW - Betonfahrbahndecken KW - Fuge KW - Fugenfüllsysteme KW - Untersuchungsmethodik KW - Leistungsermittlung KW - Dauerhaftigkeit KW - Funktionsfähigkeit PY - 2023 DO - https://doi.org/10.53184/STA11-2023-4 VL - 74 IS - 11 SP - 916 EP - 926 PB - Kirschbaumverlag GmbH CY - Bonn AN - OPUS4-59141 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Meng, Birgit T1 - Betondesign digital - Potenziale für das Bauwesen N2 - Beton ist weltweit einer der wichtigsten Konstruktionswerkstoffe und zeichnet sich durch eine enorme Anpassungsfähigkeit an sich verändernde Anforderungen aus. Damit verbunden ist eine hohe und kontinuierlich zunehmende Komplexität hinsichtlich der Ausgangsstoffe, Rezepturen und des Herstellungsprozesses. Folglich setzt eine Ausschöpfung des technischen und umweltbezogenen Potenzials der Betonbauweise höchste Expertise bei den Einzelakteuren der Bauindustrie voraus. T2 - MatFo2022 „Vom Material zur Innovation: Digital, Neutral, Vital“ CY - Cologne, Germany DA - 14.11.2022 KW - Beton KW - Zement KW - Digitalisierung KW - Ontologien PY - 2022 UR - https://www.werkstofftechnologien.de/veranstaltungen/matfo2022-vom-material-zur-innovation-digital-neutral-vital AN - OPUS4-59140 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Andrés Arcones, Daniel A1 - Diercks, Philipp A1 - Robens-Radermacher, Annika A1 - Rosenbusch, Sjard Mathis A1 - Tamsen, Erik A1 - Tyagi, Divyansh A1 - Unger, Jörg F. T1 - FenicsXConcrete N2 - FenicsXConcrete is a Python package for the simulation of mechanical problems. The general PDE solving software FEniCSx is extended with classes describing experimental setups, mechanical problems, thermo-mechanical problems, additive manufacturing and sensors. KW - FEM KW - Fenics KW - Concrete modelling PY - 2023 UR - https://github.com/BAMresearch/FenicsXConcrete DO - https://doi.org/10.5281/zenodo.7780757 PB - Zenodo CY - Geneva AN - OPUS4-59121 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Unger, Jörg F. A1 - Robens-Radermacher, Annika A1 - Tamsen, Erik T1 - Data provenance - from experimental data to trustworthy simulation models and standards N2 - FAIR (findable, accessible, interoperable and reusable) data usage is one of the main principals that many of the research and funding organizations include in their strategic plans, which means that following the main principals of FAIR data is required in many research projects. The definition of data being FAIR is very general, and when implementing that for a specific application or project or even setting a standardized procedure within a working group, a company or a research community, many challenges arise. In this contribution, an overview about our experience with different methods, tools and procedures is outlined. We begin with a motivation on potential use cases for the applications of FAIR data with increasing complexity starting from a reproducible research paper over collaborative projects with multiple participants such as Round-Robin tests up to data-based models within standardization codes, applications in machine learning or parameter estimation of physics-based simulation models. In a second part, different options for structuring the data are discussed. On the one hand, this includes a discussion on how to define actual data structures and in particular metadata schema, and on the other hand, two different systems for storing the data are discussed. The first one is the openBIS system, which is an open-source Lab notebook and PostgreSQL based data management system. A second option are a semantic representations using RDF based ontologies for the domain of interest. In a third section, requirements for workflow tools to automate data processing are discussed and their integration into reproducible data analysis is presented with an outlook on required information to be stored as metadata in the database. Finally, the presented procedures are exemplarily demonstrated for the calibration of a temperature dependent constitutive model for additively manufactured mortar. Metadata schemata for a rheological measurement setup are derived and implemented in an openBIS database. After a short review of a potential numerical model predicting the structural build-up behaviour, the automatic workflow to use the stored data for model parameter estimation is demonstrated. T2 - 4th International Congress on Materials & Structural Stability CY - Rabat, Morocco DA - 08.03.2023 KW - Data provenance KW - Experimental data to trustworthy KW - Simulation models and Standards PY - 2023 UR - https://www.rsc-cmss23.asmatec.org/RILEM%20Committees%20Program.php SP - 1 EP - 9 CY - Rabat, Morocco AN - OPUS4-57349 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Diercks, Philipp T1 - Multiscale modeling of heterogeneous structures based on a localized model order reduction approach N2 - Many of today’s problems in engineering demand reliable and accurate prediction of failure mechanisms of mechanical structures. Thus, it is necessary to take into account the heterogeneous structure on the smaller scale, to capture the underlying physical phenomena. However, this poses a great challenge to the numerical solution since the computational cost is significantly increased by resolving the smaller scale in the model. Moreover, in applications where scale separation as the basis of classical homogenization schemes does not hold, the influence of the smaller scale on the larger scale has to be modelled directly. This work aims to develop an efficient concurrent methodology to model heterogeneous structures combining the variational multiscale method (VMM) and model order reduction techniques. First, the influence of the smaller scale on the larger scale can be taken into account following the additive split of the displacement field as in the VMM. Here, also a decomposition of the global domain into subdomains, each containing a fine grid discretization of the smaller scale, is introduced. Second, local reduced approximation spaces for the smaller scale solution are constructed by exploring possible solutions for each subdomain based on the concept of oversampling and the solution of the associated transfer operator problem. Herein, we propose to choose the training data based on the solution of a reduced global problem to incorporate the actual physical behaviour of the structure of interest and to extend it by random samples to ensure sufficient approximation capabilities in general. The local reduced spaces are designed such that local contributions of each subdomain can be coupled in a conforming way. Thus, the resulting global system is sparse and reduced in size compared to the direct numerical simulation, leading to a faster solution of the problem. The authors gratefully acknowledge financial support by the German Research Foundation (DFG), project number 394350870, and by the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (ERC Grant agreement No. 818473). T2 - Model Reduction and Surrogate Modeling (MORE) CY - Berlin, Germany DA - 19.09.2022 KW - Domin decomposition KW - Model oder reduction KW - Multiscale methodes KW - Variational multiscale method PY - 2022 AN - OPUS4-57332 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - von Werder, Julia T1 - metabuilding labs: OITB presentation and how BAM an NBK can contribute N2 - The aim of the project metabuilding labs to establish an EU wide network of testing facilities and innovation services for new building envelope technologies & products is presented. Further the envisaged contribution of BAM and the private Frech research center NOBATEK is explained. T2 - ENBRI/BBRI workshop “Hygrothermal testing – a necessity to guarantee durable buildings” CY - Brussels, Belgium DA - 21.09.2022 KW - Building envelope KW - Building facade KW - Test bench KW - Pilot building KW - Open innovation testbed PY - 2022 AN - OPUS4-56389 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Unger, Jörg F. T1 - A Database for Analyzing Round Robin Data N2 - FAIR (findable, accessible, interoperable and reusable) data usage is one of the main principals that many of the research and funding organizations include in their strategic plans, which means that following the main principals of FAIR data is required in many research projects. The definition of data being FAIR is very general, and when implementing that for a specific application or project or even setting a standardized procedure within a working group, a company or a research community, many challenges arise. In this contribution, an overview about our experience with different methods, tools and procedures is outlined. We begin with a motivation on potential use cases for the applications of FAIR data with increasing complexity starting from a reproducible research paper over collaborative projects with multiple participants such as Round-Robin tests up to data-based models within standardization codes, applications in machine learning or parameter estimation of physics-based simulation models. In a second part, different options for structuring the data are discussed. On the one hand, this includes a discussion on how to define actual data structures and in particular metadata schema, and on the other hand, two different systems for storing the data are discussed. The first one is the openBIS system, which is an open-source Lab notebook and PostgreSQL based data management system. A second option are a semantic representations using RDF based ontologies for the domain of interest. In a third section, requirements for workflow tools to automate data processing are discussed and their integration into reproducible data analysis is presented with an outlook on required information to be stored as metadata in the database. Finally, the presented procedures are exemplarily demonstrated for the calibration of a temperature dependent constitutive model for additively manufactured mortar. Metadata schemata for a rheological measurement setup are derived and implemented in an openBIS database. After a short review of a potential numerical model predicting the structural build-up behaviour, the automatic workflow to use the stored data for model parameter estimation is demonstrated. T2 - RILEM Spring Convention CY - Rabat, Morocco DA - 06.03.2023 KW - Database for Analyzing KW - Round Robin Data KW - Safety in technology and chemistry PY - 2023 AN - OPUS4-57348 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Pirskawetz, Stephan T1 - Richtlinie „Detektion von Spanndrahtbrüchen mit Schallemission“ N2 - Ein großer Teil unserer Brücken wurden in den 1950er bis 1970er Jahren als Spannbetonbrücken gebaut. Mit der damals noch relativ jungen Technologie entstanden elegante, teilweise gewagte Bauwerke mit großen Spannweiten, welche die Vorteile der Materialien Stahl und Beton geschickt kombinieren. Die Standsicherheit einiger dieser Brücken ist heute gefährdet. Die Ursachen liegen in der enorm gewachsenen Belastung durch Schwerverkehr, teilweise ungenügender Wartung und in konstruktiven und Materialschwächen, die der mangelnden Erfahrung mit der Technologie in der Bauzeit geschuldet sind. Ein neuralgischer Punkt der Bauwerke sind die in den Beton integrierten Spannglieder. Infolge von Korrosion und Ermüdung können Elemente der Spannglieder reißen, wodurch die für das Tragwerk notwendige Spannung und somit die Tragfähigkeit reduziert werden. Nicht bei allen Brücken kündigen sichtbare Risse im Beton oder auffällige Verformungen den Tragfähigkeitsverlust bzw. das finale Versagen rechtzeitig an. Die Schallemissionsanalyse ist die derzeit einzige Methode, das Reißen einzelner Spannstähle zuverlässig und mit wirtschaftlich vertretbarem Aufwand zu detektieren. Trotzdem es schon einige Spannbetonbauwerke gibt, die mit Schallemissionsanalyse überwacht werden, ist das Verfahren noch wenig bekannt. Außerdem fehlen technische Richtlinien, was die Ausschreibung und Vergabe von entsprechenden Aufträgen und die Bewertung der Angebote sehr erschwert. Um sowohl Baulastträger als auch Dienstleistungsanbieter in den Vergabeverfahren und im Betrieb der Monitoringsysteme zu unterstützen, hat sich eine Gruppe von Experten aus den Bereichen Bauingenieurwesen und Schallemission zum Entwurf einer Richtlinie „Detektion von Spanndrahtbrüchen mit Schallemission“ zusammengefunden. Mit diesem Beitrag wird die Richtlinie vorgestellt, deren Bearbeitung bis zur SCHALL 23 abgeschlossen sein soll. T2 - SCHALL 23 Entwicklung und Anwendung der Schallemissionsanalyse und Zustandsüberwachung mit geführten Wellen CY - Wetzlar, Germany DA - 21.03.2023 KW - Spannbeton KW - Brücke KW - Spannstahlbruch KW - Schallemission KW - Richtlinie PY - 2023 AN - OPUS4-57391 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Herrmann, Ralf T1 - SHM system integration and experiments at a high speed railway bridge N2 - The long-term preservation of our infrastructure requires not only intelligent sensor technology and highly developed monitoring procedures, but also innovative digital tools for analyzing, evaluating and utilizing the results. This includes mathematical and, in particular, probabilistic methods for damage detection and tracking as well as for calculating service life and maintenance cycles and data management. The example project Maintal Bridge Gemuenden as part of the AISTEC project shows the workflow for the implementation of structural health monitoring and experimental tests with a train of Deutsche Bahn. The influence lines, as one possible way for damage detection, were measured with a highly accurate GNSS System to locate the trains position when crossing the bridge. The results were compared to measurements from 1987 just before the bridge went in operation. T2 - Structural Health Monitoring Using Statistical Pattern Recognition CY - Berlin, Germany DA - 20.03.2023 KW - SHM KW - Maintal Bridge Gemuenden KW - Load Test KW - Damage Detection KW - Railway PY - 2023 AN - OPUS4-57242 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Gerards-Wünsche, Paul T1 - A framework for assessing the reliability of crack luminescence – an automated fatigue crack detection system N2 - The new crack luminescence method offers the possibility of making fatigue surface cracks in metallic materials more visible during inspections through a special coating system. This coating system consists of two layers, whereby the first layer has fluorescent properties and emits visible light as soon as it is irradiated by UV light. The top layer is black and is designed to prevent the fluorescent layer from emitting if no crack develops in the underlying material. The technique proved particularly useful in a wide variety of fatigue tests of steel components under laboratory conditions. Moreover, it has the potential to be used in various industrial applications. To enable industrial deployment and integration into maintenance strategies, a concept study is developed in this contribution, resulting in a qualification framework that can serve as a foundation for determining the reliability of the crack luminescence system in terms of a probability of detection curve. Within this study, factors causing measurement variability and uncertainty are being determined and their influences assessed. Due to the extension of the system by a moving computer vision system for automated crack detection using artificial intelligence, additional long-term effects associated with structural health monitoring systems need to be incorporated into an extended probability of detection study as part of the technical justification. Finally, important aspects and findings related to design of experiments are discussed, and a framework for reliability assessment of a new optical crack monitoring method is presented, emphasizing the influence of various uncertainty parameters, including long-term effects such as system ageing. T2 - SPIE Conference Smart Structures + Nondestructive Evaluation 2023 CY - Long Beach, CA, USA DA - 24.03.2023 KW - Structural Health Monitoring KW - Non-Destructive Evaluation KW - Probability of Detection KW - Reliability KW - Artificial Intelligence KW - Computer Vision KW - Crack Luminescence PY - 2023 AN - OPUS4-57245 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hering, Marcus A1 - Fiedler, Georg A1 - Schubert, T. A1 - Hille, Falk A1 - Hüsken, Götz A1 - Beckmann, B. A1 - Grunwald, Marcel A1 - Redmer, Bernhard A1 - Rogge, Andreas T1 - Investigation of multiple impact-damaged reinforced concrete structures as a reference for liquid penetration behavior and tomographic studies N2 - The structural integrity of outer reinforced concrete (RC) containments of nuclear power plants provides an essential shield against external hazards. If this containment is damaged by an impact event, such as an aircraft crash, the question arises to which degree the reinforced concrete containment still has its protective capability. This concerns both purely structural protection and protection against liquids penetrating the interior of the containment. Due to the dimensions of the containment structures, it is difficult to perform real scale impact experiments, so in the past decades plate geometries at medium scale have been used for investigations. Detailed investigations on the structural behaviour of RC members or RC plates subjected to impact loading have already been presented in Just et al., Hering, Hering et al., Bracklow et al., Hille et al. and Nerger et al. The following investigations deal with the single and multiple impact event (first hard impact and/or subsequent soft impact) on a RC specimen, which provides the basis for further investigations. A description of the test setup and the test procedure as well as a presentation of the test results from the impact tests are provided. Furthermore, the experimental program is presented, which the damaged RC specimens are to undergo to deal with the question of how much the impact-damaged RC structure has become permeable to liquid media, such as water and kerosene, depending on the intensity of the impact. The aim of these following investigations is to develop a test setup that can be applied to investigate the liquid penetration behaviour (LPB) of small, medium, and large-scale RC members. In addition to the liquid penetration experiments, the damaged specimens are to be examined by planar tomography to obtain the damage inside the specimen. The combination of damaging event, fluid penetration behaviour and tomography should enable a comprehensive understanding of the damage to the RC specimen. T2 - Conference: 27th International Conference on Structural Mechanics in Reactor Technology (SMiRT) CY - Yokohama, Japan DA - 04.03.2024 KW - Drop tower KW - Hard impact KW - Soft impact KW - Multiple impact PY - 2024 SP - 1 EP - 10 PB - IASMiRT CY - Yokohama, Japan AN - OPUS4-59723 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Diercks, Philipp A1 - Veroy, K. A1 - Robens-Radermacher, Annika A1 - Unger, Jörg F. T1 - Multiscale modeling of linear elastic heterogeneous structures via localized model order reduction N2 - In this paper, a methodology for fine scale modeling of large scale linear elastic structures is proposed, which combines the variational multiscale method, domain decomposition and model order reduction. The influence of the fine scale on the coarse scale is modelled by the use of an additive split of the displacement field, addressing applications without a clear scale separation. Local reduced spaces are constructed bysolving an oversampling problem with random boundary conditions. Herein, we inform the boundary conditions by a global reduced problem and compare our approach using physically meaningful correlated samples with existing approaches using uncorrelated samples. The local spaces are designed such that the local contribution of each subdomain can be coupled in a conforming way, which also preserves the sparsity pattern of standard finite element assembly procedures. Several numerical experiments show the accuracy and efficiency of the method, as well as its potential to reduce the size of the local spaces and the number of training samples compared to the uncorrelated sampling KW - Multiscale methods KW - Variational multiscale method KW - Localized model order reduction KW - Proper orthogonal PY - 2024 UR - https://arxiv.org/abs/2201.10374 DO - https://doi.org/10.48550/arXiv.2201.10374 PB - Arxiv; Cornell Tech CY - New York, NY AN - OPUS4-59803 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Diercks, Philipp T1 - An efficient localized model order reduction framework for the shape optimization of additively manufactured lattice structures N2 - A common engineering practice is to optimize the geometry of a structure by an iterative process, in which an objective function is minimized by systematically choosing the value of design variables and computing the value of the objective function many times. However, regarding multiscale problems, this direct numerical approach is not feasible for a number of reasons. The model has to take into account both the structural and unit cell (UC) scale, because the objective function to be minimized is a global quantity, while the parameters are related to the shape or material parameters of the UC. In the absence of a clear separation of scales, the direct resolution of both scales in the numerical model leads to a significant increase in computational cost, which makes it impossible to repeatedly evaluate the model during the optimization process. The main goal of this contribution is to overcome the aforementioned limitations and develop a new efficient computational framework for the optimal design of lattice structures. To this end, parametric MOR is combined with DD methods. The change in geometry of each UC within the lattice is modelled by introducing a transformation that maps the reference to the physical domain. In offline simulations, suitable localized approximation spaces, that account for the change in geometry of the UC and its neighbours, are constructed using the concept of oversampling and random sampling. These are then integrated into a dual DD framework to derive a robust and scalable solver, i.e. a fast-to-evaluate reduced order model (ROM). The ROM is validated on the example of optimizing a concrete arc or pre-stressed multi beam structure minimizing its mass. T2 - 9th European Congress on Computational Methods in Applied Sciences and Engineering CY - Lisbon, Portugal DA - 03.06.2024 KW - Multiscale methods KW - Domain Decomposition KW - Model order reduction KW - Parameterized PDEs PY - 2024 AN - OPUS4-60412 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Baeßler, Matthias A1 - Aubram, Daniel T1 - Vorstellung OWA VERBATIM N2 - Das Risiko von Pfahlfussbeulen ist ein wesentlicher Grund für hohe Pfahlwandstärken bei Monopiles. Das Projekt VERBATIM - Verifikation des Beulnachweises und –verhaltens großer Monopiles zielte darauf ab, Beulphänomene zu untersuchen, die sich sowohl auf die plastischen Verformungen der Pfahlspitze während der Installation als auch auf das Beulen des eingebetteten Pfahls in der Nähe des Seebodens beziehen. Auf der Basis aufwändiger Versuche wurden numerische Modelle entwickelt und validiert. Dies ermöglicht ein besseres Verständnis des Beulverhaltens, um die Wanddicke zu reduzieren, was Kosteneinsparungen bei der Stahlmenge sowie die Entwicklung sicherer und optimierter Strukturen erlaubt. Die bisherigen Designverfahren konnten die erfolgreiche Installation der Monopiles gewährleisten. Da die Größe von Monopiles jedoch stetig zunimmt, wird die Entwicklung verbesserter Designverfahren für sichere und kostengünstige Fundamente immer wichtiger. Der Rückenwind-Vortrag gibt eine Übersicht zu den durchgeführten Untersuchungen und Ergebnissen T2 - Rückenwind Aktuelles aus der Windenergieforschung (PTJ) CY - Online meeting DA - 21.06.2024 KW - Offshore Windenergy Pile Buckling PY - 2024 AN - OPUS4-60349 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Baeßler, Matthias A1 - Eichner, Lukas A1 - Weise, Sigurd T1 - Digital building management for OWEC-structures N2 - The presentation summarizes the data management and Digital modeling processes in the recurring inspection of wind turbines as developed in DiMoWind-Inspect. T2 - Windforce 2024 CY - Bremerhaven, Germany DA - 10.06.2024 KW - DiMoWind RDS-PP Maintenance Digital Twin Offshore Wind Energy PY - 2024 AN - OPUS4-60351 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Baeßler, Matthias A1 - Weise, Sigurd T1 - Digitalization of Maintenance Processes N2 - Main aspects of Digitalization of Maintenance Processes are summarized and discussed. Introduction to the Windforce2024 session organised by BAM. T2 - Windforce 2024 CY - Bremerhaven, Germany DA - 11.06.2024 KW - Maintenance Digital Twin Offshore Wind Energy PY - 2024 AN - OPUS4-60350 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Eichner, Lukas A1 - Schneider, Ronald A1 - Baeßler, Matthias T1 - Probabilistische Systemidentifikation einer Versuchsstruktur für Substrukturen von Offshore-Windenergieanlagen mit statischen und dynamischen Messdaten N2 - In diesem Beitrag wird ein probabilistischer Ansatz zur Systemidentifikation für Tragstrukturen von Offshore-Windkraftanlagen vorgestellt. Der Schwerpunkt der Forschung liegt auf der Integration von globalen Systemantworten in Form von Eigenfrequenzen und -formen sowie Verschiebungen und Dehnungen als lokale Messdaten. Die unterschiedlichen Daten werden kombiniert für die Aktualisierung der Parameter eines Finite-Elemente-Modells genutzt. Zu diesem Zweck wird ein probabilistischer Ansatz nach Bayes verfolgt, um Vorwissen sowie Unsicherheiten einzubeziehen. Die Methodik wird bei einer Versuchsstruktur angewandt, die eine Jacket-Substruktur von Offshore-Windenergieanlagen nachbildet. Eine Systemidentifikation mit Hilfe von Überwachungsdaten ist wertvoll für Jacket-Substrukturen, da eine Zustandsanalyse für die Gewährleistung der strukturellen Integrität unerlässlich ist, aber hinsichtlich der schwierigen Offshore-Bedingungen möglichst effizient sein muss. In diesem Zusammenhang schafft diese Arbeit die Grundlage für eine Schadenserkennung, eine verbesserte Vorhersage der Ermüdungslebensdauer und optimierte Instandhaltungsstrategien. Während das Modell hinsichtlich der statischen Messdaten erfolgreich aktualisiert werden kann, sind Schwierigkeiten bei der Identifizierung der dynamischen Systemeigenschaften erkennbar. T2 - 8. VDI-Fachtagung Baudynamik 2025 CY - Würzburg, Germany DA - 02.04.2025 KW - Systemidentifikation KW - Versuchsstruktur KW - Jacket KW - Offshore-Windenergie PY - 2025 VL - 8 SP - 175 EP - 188 AN - OPUS4-62879 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Pirskawetz, Stephan A1 - Weise, Frank A1 - Rieffel, Y. A1 - Gorbushina, Anna T1 - Die Schlossbrücke Berlin - Schutz der Göttinnen N2 - Vielleicht nannten es die Berliner „Puppen putzen“, wenn in den 1880er Jahren die Marmorstatuen auf der Schlossbrücke vor dem Berliner Stadtschloss mit Bürste, Wasser und Seife von Staub, Ruß und Taubendreck befreit wurden. Soviel Pflege wurde diesen Göttinnen aus der griechischen Mythologie nicht immer zuteil. So haben Klima, Luftverschmutzung und der 2. Weltkrieg, wie bei anderen Kunstwerken auch, tiefe Spuren hinterlassen. Der Erhalt dieser zwischen 1847 und 1857 aufgestellten Skulpturen und vieler vergleichbarer Objekte im Stadtbild ist durch die auch heute weiter fortschreitende Schädigung des Marmors gefährdet. In den Jahren 2006 bis 2010 förderte die Deutsche Bundesstiftung Umwelt (DBU) ein Projekt zur „Entwicklung und Überprüfung von Einhausungssystemen zur Reduzierung umweltbedingter Schädigungen von außenexponierten Marmorobjekten mit dem Ziel des langfristigen Erhalts in situ an einem national bedeutenden Objektkomplex, den Schlossbrückenfiguren unter den Linden, Berlin“. Geleitet und restauratorisch betreut wurde das Projekt durch das Landesdenkmalamt (LDA) Berlin. Durch die Abteilung Strukturgeologie und Geodynamik (GZG) der Georg-August Universität Göttinnen wurden die Verwitterungsmechanismen des Marmors untersucht und auf dieser Basis Anforderungen an das Schutzsystem formuliert. Anhand von numerischen Simulationen des Instituts für Bauklimatik der Technischen Universität Dresden (TUD) wurde das bauphysikalische Konzept des Einhausungssystems optimiert. Die konstruktive Gestaltung eines Prototyps und des finalen Entwurfs erfolgte durch das Fachgebiet Konstruktives Entwerfen und Tragwerkslehre der Universität der Künste Berlin. Durch den Fachbereich Baustoffe der BAM erfolgten die Realisierung des Prototyps der Einhausung sowie ein umfangreiches Klimamonitoring an den Skulpturen. Anhand dieses interdisziplinären Projektes und ergänzt durch weitere Messungen wird gezeigt, mit welchen Methoden die für die Degradation von Marmor relevanten Mechanismen untersucht werden können. Die Erkenntnisse aus dem Projekt sind die Grundlage für die Entwicklung nachhaltiger Pflege- und Schutzkonzepte für die kulturhistorisch wertvollen Skulpturen. Nur mit solchen modernen konservatorischen Programmen können die Originalskulpturen im Berliner Stadtraum erlebbar bleiben. T2 - Workshop Kulturerhaltung - Vom Dampfkessel zu Nanomaterialien CY - Berlin, Germany DA - 17.11.2021 KW - Baustoffe KW - Marmor KW - Verwitterung KW - Kulturelles Erbe KW - Wintereinhausungen KW - Klima KW - Zerstörungsfreie Prüfung KW - Building materials KW - Marble KW - Degradation KW - Cultural heritage KW - Winter shelters KW - Climate KW - Nondestructive testing PY - 2021 SN - 2567-1251 VL - 3 SP - 87 EP - 96 PB - Druckerei G. Bohm CY - Berlin AN - OPUS4-54637 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Omidalizarandi, M. A1 - Herrmann, Ralf A1 - Kargoll, B. A1 - Marx, S. A1 - Paffenholz, J. A1 - Neumann, I. T1 - A validated robust and automatic procedure for vibration analysis of bridge structures using MEMS accelerometers N2 - Today, short- and long-term structural health monitoring (SHM) of bridge infrastructures and their safe, reliable and cost-effective maintenance has received considerable attention. From a surveying or civil engineer’s point of view, vibration-based SHM can be conducted by inspecting the changes in the global dynamic behaviour of a structure, such as natural frequencies (i. e. eigenfrequencies), mode shapes (i. e. eigenforms) and modal damping, which are known as modal parameters. This research work aims to propose a robust and automatic vibration analysis procedure that is so-called robust time domain modal parameter identification (RT-MPI) technique. It is novel in the sense of automatic and reliable identification of initial eigenfrequencies even closely spaced ones as well as robustly and accurately estimating the modal parameters of a bridge structure using low numbers of cost-effective micro-electro-mechanical systems (MEMS) accelerometers. To estimate amplitude, frequency, phase shift and damping ratio coefficients, an observation model consisting of: (1) a damped harmonic oscillation model, (2) an autoregressive model of coloured measurement noise and (3) a stochastic model in the form of the heavy-tailed family of scaled t-distributions is employed and jointly adjusted by means of a generalised expectation maximisation algorithm. Multiple MEMS as part of a geo-sensor network were mounted at different positions of a bridge structure which is precalculated by means of a finite element model (FEM) analysis. At the end, the estimated eigenfrequencies and eigenforms are compared and validated by the estimated parameters obtained from acceleration measurements of high-end accelerometers of type PCB ICP quartz, velocity measurements from a geophone and the FEM analysis. Additionally, the estimated eigenfrequencies and modal damping are compared with a well-known covariance driven stochastic subspace identification approach, which reveals the superiority of our proposed approach. We performed an experiment in two case studies with simulated data and real applications of a footbridge structure and a synthetic bridge. The results show that MEMS accelerometers are suitable for detecting all occurring eigenfrequencies depending on a sampling frequency specified. Moreover, the vibration analysis procedure demonstrates that amplitudes can be estimated in submillimetre range accuracy, frequencies with an accuracy better than 0.1 Hz and damping ratio coefficients with an accuracy better than 0.1 and 0.2 % for modal and system damping, respectively. KW - Vibration analysis KW - Automatic modal parameters identification KW - MEMS KW - FEM analysis KW - Bridge monitoring PY - 2020 UR - https://www.degruyter.com/view/journals/jag/14/3/article-p327.xml DO - https://doi.org/10.1515/jag-2020-0010 SN - 1862-9016 VL - 14 IS - 3 SP - 1 EP - 28 PB - De Gruyter CY - Berlin AN - OPUS4-51338 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Titscher, Thomas A1 - Unger, Jörg F. T1 - Efficient higher-order cycle jump integration of a continuum fatigue damage model N2 - Simulating high-cycle fatigue with continuum models offers the possibility to model stress-redistributions, consider 3Dstress states and simplifies extensions to multi-physics problems. The computational cost of conventional cycle-by-cycle time integrations is reduced by reformulating the fatigue problem as an ordinary differential equation for the material state and solving it with high-order adaptive time integration schemes. The computational cost of calculating the Change of the material state in one cycle is further reduced by a high-order fatigue-specific time integration. The approach is exemplarily demonstrated for a fatigue extension of the implicit gradient-enhanced damage model in 3D and compared to experimental Wöhler lines. KW - Cycle jump KW - Temporal multiscale KW - Fatigue modeling KW - Continuum damage mechanics KW - Regularized damage models PY - 2020 DO - https://doi.org/10.1016/j.ijfatigue.2020.105863 VL - 141 SP - 105863 PB - Elsevier Ltd. AN - OPUS4-51101 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schneider, Ronald A1 - Herrmann, Ralf T1 - Sensorbasiertes Monitoring der Maintalbrücke Gemünden N2 - Monitoringsysteme erfassen kontinuierlich Bauwerksdaten wie z.B. Bauwerksbeschleunigungen, auf deren Grundlage Bauwerksschäden mit Hilfe von SHM-Methoden quantifiziert werden können. Mit den gewonnenen Informationen über den aktuellen Bauwerkszustand können Vorhersagen des Bauwerkszustandes und der Bauwerkszuverlässigkeit aktualisiert und erforderliche Inspektionen und Instandhaltungsmaßnahmen vorausschauend geplant werden. Im BMBF-Forschungsvorhaben AISTEC entwickeln der Fachbereich 7.2 „Ingenieurbau“ innovative Monitoringverfahren zur Systemidentifikation und automatischen Detektion, Lokalisierung und Quantifizierung von Schäden an Infrastrukturbauwerken anhand von gemessenen dynamischen und statischen Bauwerksdaten. Im Rahmen dieses Projektes werden die Verfahren an der Maintalbrücke bei Gemünden angewendet, welche Teil der ICE-Strecke Hannover-Würzburg ist. In diesem Vortrag wird das für die Maintalbrücke Gemünden geplante und umgesetzte Monitoingsystem vorgestellt. T2 - 4. Verbundtreffen AISTEC CY - Weimar, Germany DA - 24.09.2020 KW - Zivile Sicherheit KW - Brücken KW - Structural Health Monitoring PY - 2020 AN - OPUS4-51333 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Thiele, Marc T1 - Fatigue crack detection methods for high-cyclic loaded steel structures and challenges in mechanical testing N2 - For the generation of renewable energy offshore wind farms play an important role. The majority of these wind generators are connected to steel foundation structures. Steady increasing power output of these wind turbines leads to new challenges as well for engineers of the related support structures. Caused by the high-cyclic loading of these structures by wind and waves fatigue plays a very important role. Besides the consideration of fatigue within the design process it is additionally an important topic and challenge to monitor the existing steel structures relating to potential fatigue cracks occurring during their lifetime. This plays a role for a fundamental understanding of mechanisms as investigated in testing but also for inspection in real structures. Since the structures of the offshore wind generators are very large and in addition partially under water effective and reliable methods for fatigue crack detection are required. This contribution will present results of recent investigations on different crack detection methods applied on high-cycle fatigue tests on small welded steel samples as well as on welded steel components. The comparison of these measurements will show what are the advantages and disadvantages of the different methods and which method is potentially more suitable for the application on real offshore wind structures. It is outlined where challenges for detection methods exist. Furthermore, in this context the resulting challenges for the execution of material testing especially caused by the increasing dimensions of wind energy converters will by exemplarily presented. T2 - EERA JP Wind & SETWind Online Annual Event 2020 CY - Online meeting DA - 14.09.2020 KW - Fatigue KW - Crack detection KW - Steel structures PY - 2020 AN - OPUS4-51356 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - von Werder, Julia A1 - Bilgin, S. A1 - Hoppe, Johannes A1 - Fontana, P. A1 - Meng, Birgit ED - Middendorf, B. ED - Fehling, E. ED - Wetzel, A. T1 - Composite UHPC facade elements with self-cleaning surface: Aspects of technological manufacturing N2 - In the framework of the European collaborative project H-House, which was finished in 2017, large façade elements were developed consisting of a box shaped external shell of ultra-high-performance concrete (UHPC) with a functionalized surface and an insulation of autoclaved aerated concrete (AAC). The exposed concrete of the elements was further refined by adding self-cleaning properties to the surface through imprinting a microstructure in combination with chemical agents directly in the casting process. The paper focuses on selected technological aspects of the manufacturing process of large-scale prototypes. Presented are results of the upscaling process of functionalized surfaces from small specimen up to large UHPC composite facade elements produced for the construction of a demonstrator. T2 - 5th International Symposium on Ultra-High Performance Concrete and High Performance Construction Materials (HiPerMat 2020) CY - Kassel, Germany DA - 11.03.2020 KW - Ultra-High Performance Concrete KW - Facade Elements KW - Self-Cleaning Properties KW - Architectural Concrete PY - 2020 SN - 978-3-7376-0828-2 DO - https://doi.org/10.17170/kobra-202002271026 IS - 32 SP - 51 EP - 52 PB - kassel university press CY - Kassel AN - OPUS4-51908 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Siegesmund, S. A1 - Pirskawetz, Stephan A1 - Weise, Frank A1 - Plagge, R. A1 - Rieffel, Y. ED - Siegesmund, S. ED - Middendorf, B. T1 - Winter Shelters For Marble Sculptures Of The Schlossbrücke Berlin: Climatic Constraints N2 - The long-term exposure of marble objects leads to a successive deterioration of the rock fabric and may cause severe damage on cultural heritage objects. The magnitude of disintegration depends on the rock fabric as well as on the climatic conditions. Some types of marble show no considerable damage even if they have been exposed in northern Europe for several decades or centuries. In contrast, other marble varieties are showing severe damage after a few years of weathering. The present study shows that marble decay, along with the initial thermal degradation, is mainly influenced by the hygric and thermo-hygric load, respectively. The influence of the rock fabric on the resistivity against weathering is also documented. The factors causing marble decay were compared to extensive climate data, which were collected during a scientific project that was started with the aim to develop a covering system for marble sculptures in Berlin. Based on the hygrothermal material properties of the marble and on the climatic conditions, the heat and moisture Transport inside the material and hence the hygrothermal load changes were calculated with a high spatial resolution. The calculations showed that the temperature and moisture fluctuations inside the material are mainly controlled by the dimensions and orientation of the sculptural elements. The current state of preservation was investigated by two-dimensional ultrasonic tomography. The results show a good correlation to the calculated distribution of the hygrothermal load. Based on this finding, requirements on a protective winter shelter system for the sculptures were defined. The project results show that in addition to protective covers, regular inspection and maintenance combined with regular cleaning ensures an effective and sustainable protection of marble objects in northern Europe. T2 - 14th International Congress on the Deterioration and Conservation of Stone CY - Göttingen, Germany DA - 07.09.2020 KW - Schlossbrücke KW - Marble decay KW - Weathering processes KW - Ultrasound wave velocities KW - Climatic impact KW - Numerical simulation KW - Maintenance PY - 2020 SN - 978-3-96311-172-3 SP - 709 EP - 716 PB - mdv Mitteldeutscher Verlag GmbH CY - Halle (Saale) AN - OPUS4-51916 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hüsken, Götz A1 - Shamsuddoha, Md A1 - Pirskawetz, Stephan A1 - Hofmann, Detlef A1 - Baeßler, Matthias A1 - Kühne, Hans-Carsten T1 - Potential of a Repair System for Grouted Connections in Offshore Structures: Development and Experimental Verification N2 - Grouted connections are intensively used in offshore rigs, platforms as well as jacket and monopile offshore wind turbine structures. Being located in remote offshore conditions, these connections can experience considerable adverse loading during their lifetimes. Degradation was reported inside similar connections, which were installed in the last three decades. Grouting in the offshore sites may often be proven difficult, which eventually leads to reduced load-bearing capacity of connections in the long run. Thus, repair and rehabilitation of such connections should be planned ahead to minimize operational delays and costs. In this study, scaled grouted connections were manufactured using a novel mould, whose integrity were monitored using digital image correlation (DIC). The connections were loaded under static load to visualize the main failure pattern using distributed fibre optic sensors and acoustic emission (AE) analysis. Grouted connections were then repaired using a cementitious injectable grout. The effectiveness of the grout injection was monitored using dye penetration technique. Finally, specimens are reloaded to identify the potential of such repair for grouted connections. KW - Offshore KW - Grouted connection KW - Fibre optic sensors KW - Acoustic emission analysis KW - Cracks KW - Repair KW - Rehabilitation KW - Static loading PY - 2021 DO - https://doi.org/10.1016/j.marstruc.2021.102934 VL - 77 SP - 102934 PB - Elsevier Ltd. AN - OPUS4-52059 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Diercks, Philipp T1 - A variational multiscale method to model linear elastic heterogeneous structures N2 - Many of today’s problems in engineering demand reliable and accurate prediction of failure mechanisms of mechanical structures. Herein it is necessary to take into account the often heterogeneous structure on the fine scale, to capture the underlying physical phenomena. Despite ever increasing Computational resources, dissolving the fine scales in a direct numerical simulation is prohibitive. This work aims to develop an efficient approach to modeling nonlinear heterogeneous structures using the variational multiscale method (VMM) and model order reduction (MOR). The VMM, introduced in, assumes an additive split of the solution into coarse and fine scale contributions. In, the VMM is applied to a damage mechanics–based material model for concrete-like materials. Herein, suitable boundary conditions for the fine scale which enable localization phenomena to evolve are discussed. As such, zero jump conditions between fine scale solutions are proposed which are enforced pointwise by a Lagrange type method leading to a coupled solution procedure. In this contribution, possible extensions of the VMM with reduced order modeling are presented. In the linear case, assuming the fine scale solution to be zero on coarse scale element boundaries allows for static condensation and a decoupled solution procedure. Based on this, an efficient localized Training strategy will be developed. For the nonlinear case, the situation of coupled non-conforming spaces, i. e. finite element and reduced order spaces for the fine scales, arises. Thus the imposition of suitable fine scale interface conditions in the weak sense by the use of Lagrange multipliers is investigated. Specific problems in solid mechanics are used to illustrate the performance of the above approaches. The authors gratefully acknowledge financial support by the German Research Foundation (DFG), Project number 394350870, and by the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (ERC Grant agreement No. 818473). T2 - WCCM-ECCOMAS Congress CY - Online meeting DA - 11.01.2021 KW - Model Order Reduction KW - Variational Multiscale Method KW - Multiscale Methods PY - 2021 AN - OPUS4-52198 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Unger, Jörg F. T1 - Stochastische Modellkalibrierung eines digitalen Zwillings N2 - Ein Digitaler Zwilling repräsentiert ein reales Objekt in der digitalen Welt. Die Digitalen Zwillinge sind aus Daten und Modellen/Algorithmen aufgebaut und kontinuierlich über Sensoren mit der realen Welt gekoppelt. Anwendung z.B. Modellbewertung, Monitoring, Schadensdetektion. T2 - DVM-Online-Workshop "Grundlagen und Beispiele zur Digitalisierung für die Materialforschung und -prüfung" CY - Online meeting DA - 20.10.2020 KW - Modellkalibrierung KW - Stochastischen Verfahren KW - Realtime model updating KW - Demonstrator PY - 2020 AN - OPUS4-52175 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kühne, Hans-Carsten T1 - Handlungshilfe zur Betoninstandsetzung N2 - Die TR Instandhaltung des Deutschen Instituts für Bautechnik wird als maßgebliches Bezugswerk der Betoninstandsetzung ür die Fachöffentlichkeit hinsichtlich ihrer Inhalte und Zielrichtung vorgestellt KW - Beton KW - Instandsetzung KW - Technische Regel KW - Planung KW - Ausführung KW - DIBt PY - 2021 UR - https://www.ingenieur.de/fachmedien/bauingenieur/ PB - VDI Fachmedien GmbH & Co. KG Unternehmen für Fachinformationen CY - Düsseldorf AN - OPUS4-52117 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Nerger, Deborah A1 - Moosavi, Robabeh A1 - Bracklow, F. A1 - Hering, M. A1 - Kühn, T. A1 - Curbach, M. A1 - Hille, Falk A1 - Rogge, Andreas T1 - Planar tomography and numerical analysis for damage characterization of impact loaded RC plates N2 - The damage analysis of reinforced concrete (RC) is of high interest for reasons of effective maintenance and structural safe-ty of buildings. The damage structures of RC plates loaded by an impact were investigated, applying X-ray planar tomogra-phy and finite element method (FEM). Planar tomography allows getting three-dimensional information of the RC elements and the damage including crack, spalling and scabbing. The FEM model validated on the tomography data justifies the appli-cation for further predictions of the damage description. In this study, we investigated concrete plates of three different thick-ness subjected to impacts at different low- and medium-velocity, whereby the used impactor had a flat tip, which resulted in small penetrations on the front side and scabbing on the rear side. In order to quantify the damage, the damage volume and its distribution through the plate were computed and the correlations between degree of damage and impact velocity were found out. KW - Impact KW - Damage characterization KW - Planar tomography KW - Numeric simulation KW - Reinforced concrete structure PY - 2020 DO - https://doi.org/10.1002/cend.202000017 VL - 8 SP - 1 EP - 19 PB - Wiley AN - OPUS4-51117 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Nerger, Deborah A1 - Hille, Falk A1 - Moosavi, Robabeh A1 - Grunwald, Marcel A1 - Redmer, Bernhard A1 - Kühn, T. A1 - Hering, M. A1 - Bracklow, F. T1 - Post-impact evaluation at RC plates with planar tomography and FEM N2 - Due to the wide range of applications, the easy production and the large field of use, reinforced concrete (RC) is a widespread building material. This variety of applications is reflected in a wide range of physical material properties. Not only therefor it still is a technical challenge to provide all necessary test conditions for experimentally reproducing dynamic effects under impact loading of RC structures. In this paper we present investigations on the thicknesses of RC plates under low and medium high velocity impact loading by a flat-tipped impactor. The planar tomography setup at BAM is used to visualize the impact damage and to characterize the damage features such as cracks, scabbing and spalling. Further, the comparison of tomography results with those of an applied numeric simulation analysis is used to verify the numeric models for future damage prognosis under impact loading. Using the results of both, the tomographic as well as the FE analysis, different damage features were investigated and compared regarding their validity. Crack damage plays a leading part and the significance of summarized crack values as well as their distribution is analyzed. The total damage value but also the determined damage distribution both provide an input for describing damage as a function of the impactor velocity and plate thickness. KW - Reinforced concrete structure KW - Post-impact evaluation KW - Damage characterization KW - Ansys Autodyn KW - Drucker-Prager KW - Planar tomography PY - 2020 DO - https://doi.org/10.1016/j.matpr.2020.05.671 SP - 1 EP - 10 PB - Elsevier AN - OPUS4-51115 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schneider, Ronald T1 - Kontinuierliches Bauwerksmonitoring – Sensor-basiert (AP4) N2 - Kontinuierliche sensorbasierte Bauwerksmessungen leisten einen wichtigen Beitrag zur Sicherheit von Verkehrsbauwerken. Hierzu werden im Vorhaben AISTEC Referenzbauwerke und Referenzverfahren untersucht mit Schwerpunkt auf den Einfluss klimatischer Bedingungen. Der Vortrag stellt den aktuellen Projektstand des FB 7.2 vor. T2 - 3. Verbundtreffen AISTEC CY - Online meeting DA - 05.05.2020 KW - Zivile Sicherheit KW - Brücken KW - Structural Health Monitoring PY - 2020 AN - OPUS4-50796 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Simon, Patrick A1 - Schneider, Ronald A1 - Viefhues, Eva A1 - Said, Samir A1 - Herrmann, Ralf A1 - Baeßler, Matthias ED - Papadrakis, M. ED - Fragiadakis, M. ED - Papadimitriou, C. T1 - Vibration-based Structural Health Monitoring of a Reinforced Concrete Beam Subjected to Varying Ambient Conditions Using Bayesian Methods N2 - Inspection and maintenance contribute significantly to the lifetime cost of bridges. There is significant potential in using information obtained through structural health monitoring to update predictive models of the condition and performance of such structures, and thus ena-ble an improved decision-making regarding inspection and maintenance activities. Within the AISTEC project funded by the German Federal Ministry of Education and Research, we develop vibration-based structural health monitoring systems aimed at continuously provid-ing information on the structural condition of bridges. Environmental variations such as changing ambient temperatures can significantly influence the dynamic characteristics of bridges and thus mask the effect of structural changes and damages. It remains a challenge to account for such influences in structural health monitoring. To study the effect of ambient temperatures on the dynamic characteristics of beam structures, we monitor the vibration response of a reinforced concrete beam in the uncracked and cracked state at varying tem-peratures in a climate chamber. We postulate a set of competing parameterized probabilistic structural models, which explicitly account for the effect of varying ambient temperatures on the mechanical properties of the system. We then combine the information provided by the structural models with the information contained in the recorded vibration data to learn the parameters of the temperature-dependent structural models and infer the plausible state of the beam using Bayesian system identification and model class selection. T2 - EURODYN 2020, XI International Conference on Structural Dynamics CY - Online meeting DA - 23.11.2020 KW - Structural health monitoring KW - Bayesian methods KW - Environmental effects PY - 2020 SN - 978-618-85072-2-7 SN - 978-618-85072-0-3 SP - 1254 PB - Institute of Structural Analysis and Antiseismic Research, School of Civil Engineering, National Technical University of Athens (NTUA) CY - Athens, Greece AN - OPUS4-51590 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Viefhues, Eva A1 - Döhler, M. A1 - Hille, Falk A1 - Mevel, L. T1 - Fault detection for linear parameter varying systems under changes in the process noise covariance N2 - Detecting changes in the eigenstructure of linear systems is a comprehensively investigated subject. In particular, change detection methods based on hypothesis testing using Gaussian residuals have been developed previously. In such residuals, a reference model is confronted to data from the current system. In this paper, linear output-only systems depending on a varying external physical parameter are considered. These systems are driven by process noise, whose covariance may also vary between measurements. To deal with the varying parameter, an interpolation approach is pursued, where a limited number of reference models -- each estimated from data measured in a reference state -- are interpolated to approximate an adequate reference model for the current parameter. The problem becomes more complex when the different points of interpolation correspond to different noise conditions. Then conflicts may arise between the detection of changes in the eigenstructure due to a fault and the detection of changes due to different noise conditions. For this case, a new change detection approach is developed based on the interpolation of the eigenstructure at the reference points. The resulting approach is capable of change detection when both the external physical parameter and the process noise conditions are varying. This approach is validated on a numerical simulation of a mechanical system. T2 - IFAC World Congress 2020 CY - Online meeting DA - 11.07.2020 KW - Linear parameter varying systems KW - Fault detection KW - Changing process noise KW - Subspace-based residual KW - Model interpolation PY - 2020 SP - 13858 AN - OPUS4-51617 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Titscher, Thomas T1 - Model selection and model calibration for a digital twin N2 - The quality of a model - and thus its predictive capabilities - is influenced by numerous uncertainties. They include possibly unknown boundary and initial conditions, noise in the data used for its calibration and uncertainties in the model itself. Here, the latter part is not only restricted to uncertain model parameters, but also refers to the choice of the model itself. Inferring these uncertainties in an automatic way allows for an adaption of the model to new data sets and for a reliable, reproducible model assessment. Note that similar concepts apply at the structural level, where a continuously updated digital twin allows virtual measurements at inaccessible positions of the structure and a simulation based lifetime prediction. This work presents an inference workflow that describes the difference of measured data and simulated model responses with a generic interface that is independent from the specific model or even the geometry and can easily incorporate multiple data sources. A variational Bayesian inference algorithm is then used to a) calibrate a set of models to given data and to b) identify the best fitting one. The developed concepts are applied to a bridge Demonstrator equipped with displacement sensors, force sensors and a stereophotogrammetry system to perform a system identification of the material parameters as well as a real-time identification of a moving load. T2 - 6th GAMM AG Data Workshop CY - Berlin, Germany DA - 20.10.2020 KW - Digital twin KW - Demonstrator PY - 2020 AN - OPUS4-51532 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Oesch, Tyler T1 - Analysis of the porosity of alkali-sensitive aggregates for the assessment of microstructure-dependent solubility in the context of ASR N2 - Intensified Alkali-Silica Reaction (ASR) damage has occurred on German roadways in recent years, leading to requirements for compulsory pre-construction investigation of aggregate alkali sensitivity using concrete tests with external alkali supply. However, since these tests are time-consuming and cost-intensive, there is interest in replacing them with a solubility test on pure aggregate in 0.1 M KOH solution at 80°C with a defined NaCl content (1wt.-%). In this context, the influence of aggregate pore structure on SiO2 and Al2O3 solubility was investigated in this project. This paper compares the results of porosity studies with X-ray Computed Tomography (3D-CT) and the Brunauer-Emmett-Teller (BET) method on individual quarried and river gravel granules of both rhyolite and greywacke. For visualization and quantification of both externally accessible and fully enclosed surfaces of granules using X-ray 3D-CT, special software tools were developed. The results demonstrated that the river gravel granules had significantly larger externally accessible surfaces than the quarried granules. BET measurements on individual stones showed, as expected, that measured surfaces were about three orders of magnitude larger than those from the X-ray 3D-CT analyses due to the higher spatial resolution of BET. There was no apparent correlation between the X-ray 3D-CT and BET surface areas. Mercury porosimetry measurements indicate that this may be due to the presence of significant porosity below the spatial resolution of the X-ray 3D-CT. A comparison of SiO2 and Al2O3 solubility measurements with the X-ray 3D-CT and BET surface area data resulted only in weak, inconclusive correlations, indicating the need for further experimental investigation. T2 - Microdurability Webinar CY - Online meeting DA - 12.10.2020 KW - X-ray Computed Tomography (CT) KW - Brunauer-Emmett-Teller (BET) Method KW - Alkali-Silica Reaction (ASR) KW - Porosity KW - Solubility PY - 2020 AN - OPUS4-51429 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Simon, Patrick T1 - Vibration-based Structural Health Monitoring of a Reinforced Concrete Beam Subjected to Varying Ambient Conditions Using Bayesian Methods N2 - Inspection and maintenance contribute significantly to the lifetime cost of bridges. There is significant potential in using information obtained through structural health monitoring to update predictive models of the condition and performance of such structures, and thus ena-ble an improved decision-making regarding inspection and maintenance activities. Within the AISTEC project funded by the German Federal Ministry of Education and Research, we develop vibration-based structural health monitoring systems aimed at continuously provid-ing information on the structural condition of bridges. Environmental variations such as changing ambient temperatures can significantly influence the dynamic characteristics of bridges and thus mask the effect of structural changes and damages. It remains a challenge to account for such influences in structural health monitoring. To study the effect of ambient temperatures on the dynamic characteristics of beam structures, we monitor the vibration response of a reinforced concrete beam in the uncracked and cracked state at varying tem-peratures in a climate chamber. We postulate a set of competing parameterized probabilistic structural models, which explicitly account for the effect of varying ambient temperatures on the mechanical properties of the system. We then combine the information provided by the structural models with the information contained in the recorded vibration data to learn the parameters of the temperature-dependent structural models and infer the plausible state of the beam using Bayesian system identification and model class selection. T2 - EURODYN 2020, XI International Conference on Structural Dynamics CY - Online meeting DA - 23.11.2020 KW - Bayesian methods KW - Environmental effects KW - Structural health monitoring PY - 2020 AN - OPUS4-51732 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - von Werder, Julia T1 - Composite UHPC facade elements with self-cleaning surface: Aspects of technological manufacturing N2 - In the framework of the European collaborative project H-House, which was finished in 2017, large façade elements were developed consisting of a box shaped external shell of ultra-high-performance concrete (UHPC) with a functionalized surface and an insulation of autoclaved aerated concrete (AAC). The exposed concrete of the elements was further refined by adding self-cleaning properties to the surface through imprinting a microstructure in combination with chemical agents directly in the casting process. The paper focuses on selected technological aspects of the manufacturing process of large-scale prototypes. Presented are results of the upscaling process of functionalized surfaces from small specimen up to large UHPC composite facade elements produced for the construction of a demonstrator. T2 - 5th International Symposium on Ultra-High Performance Concrete and High Performance Construction Materials (HiPerMat 2020) CY - Kassel, Germany DA - 11.03.2020 KW - Ultra-High Performance Concrete KW - Facade Elements KW - Self-Cleaning Properties KW - Architectural Concrete PY - 2020 AN - OPUS4-51912 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Viefhues, Eva T1 - Fault detection for linear parameter varying systems under changes in the process noise covariance N2 - Detecting changes in the eigenstructure of linear systems is a comprehensively investigated subject. In particular, change detection methods based on hypothesis testing using Gaussian residuals have been developed previously. In such residuals, a reference model is confronted to data from the current system. In this paper, linear output-only Systems depending on a varying external physical parameter are considered. These systems are driven by process noise, whose covariance may also vary between measurements. To deal with the varying parameter, an interpolation approach is pursued, where a limited number of reference models { each estimated from data measured in a reference state { are interpolated to approximate an adequate reference model for the current parameter. The problem becomes more complex when the different points of interpolation correspond to different noise conditions. Then con icts May arise between the detection of changes in the eigenstructure due to a fault and the detection of changes due to different noise conditions. For this case, a new change detection approach is developed based on the interpolation of the eigenstructure at the reference points. The resulting approach is capable of change detection when both the external physical parameter and the process noise conditions are varying. This approach is validated on a numerical simulation of a mechanical system. T2 - 21st IFAC World Congress CY - Berlin, Germany DA - 13.07.2020 KW - Linear parameter varying systems KW - Fault detection KW - Changing process noise KW - Subspace-based residual KW - Model interpolation PY - 2020 AN - OPUS4-52366 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Herrmann, Ralf T1 - Vorstellung des Bauwerksmonitoring der Maintalbrücke Gemünden im Vorhaben AISTEC N2 - Im Abteilungsseminar wird der aktuelle Umsetzungsstand des Bauwerksmonitorings an der Maintalbrücke Gemünden vorgestellt, sowie die nächsten Schritte zur Systemintegration von Konzepten an Realbauwerken. T2 - Abteilungs-Vortragsseminar Abteilung 7. Bauwerkssicherheit CY - Online meeting DA - 03.03.2021 KW - Structural Health Monitoring KW - Maintalbrücke Gemünden KW - Bauwerksüberwachung KW - Datenmanagement PY - 2021 AN - OPUS4-52221 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Buchheim, Janine T1 - A new approach towards performance-related design and scientific evaluation of joint sealing systems N2 - While there is a permanent improvement of concrete pavement mixtures and pavement construction types over the last decades, the state-of-the-art joint sealing materials and joint constructions seem to stagnate on an antiquated empirical level. This status has been reaffirmed in the latest European standard. The consequences in the motorway network due to unsatisfying capability and durability of joint sealing systems are unacceptable. In addition, inadequate traffic performance (noise emissions, roll-over comfort) and traffic safety losses in the joint area of concrete pavements are existing challenges. These deficits and weaknesses reflect a demand for joint sealing materials and constructions whose approval requirements take functional aspects into account. Furthermore a sufficient analysis of decisive loads and a practice-oriented method to evaluate the requirements towards performance and durability is still missed. In this contribution decisive loads to German highways are analyzed. The design of test specimen for representative functional testing of joint sealing systems is discussed. The focus is on the geometry of the test specimens and the used concrete mixture. Finally, a new approach for a function-orientated test concept that considers representative load functions is presented. The potential of this approach to validate the durability and capability of various joint sealing systems is also presented using an example. T2 - RILEM International Symposium on Bituminous Materials CY - Online Meeting DA - 14.12.2020 KW - Joint sealing KW - Expansion joint KW - Performance testing KW - Capability KW - Durability PY - 2020 AN - OPUS4-52437 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Simon, Patrick A1 - Schneider, Ronald A1 - Baeßler, Matthias ED - Yokota, H. ED - Frangopol, D. M. T1 - Bayesian system identification of a reinforced concrete beam subject to temperature variations based on static response data N2 - Changes in the measured response of structural systems can be an indication of structural damages. However, such changes can also be caused by the effect of varying environmental conditions. To detect, localize and quantify changes or damages in structural systems subject to varying environmental conditions, physics-based models of the structural systems have to be applied which explicitly account for the influence of ambient conditions on the structural behavior. Data obtained from the structural systems should be used to calibrate the models and update predictions. Bayesian system identification is an effective framework for this task. In this paper, we apply this framework to learn the parameters of two competing structural models of a reinforced concrete beam subject to varying temperatures based on static response data. The models describe the behavior of the beam in the uncracked and cracked condition. The data is collected in a series of load tests in a climate chamber. Bayesian model class selection is then applied to infer the most plausible condition of the beam conditional on the available data. T2 - Tenth International Conference on Bridge Maintenance, Safety and Management (IABMAS 2020) CY - Online meeting DA - 11.04.2021 KW - Structural systems KW - Bayesian system identification KW - Damage identification KW - Environmental effects KW - Structural health monitoring PY - 2021 DO - https://doi.org/10.1201/9780429279119-125 SP - 934 EP - 941 PB - CRC Press AN - OPUS4-52809 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schneider, Ronald T1 - Sensorbasiertes Monitoring (AP4 + AP7): Ein Überblick N2 - Im AISTEC Projekt erforscht der FB 7.2 Verfahren zur Bewertung von Verkehrsbrücken auf der Gruandlage von sensorbasierten Bauwerksmessungen. In diesem Vortrag wird ein Überlick über die Forschungsarbeiten des FB 7.2 präsentiert. Des Weiteren wird ein Ausblick zur quantitativen Integration von sensorbasierten Bauwerksmessungen in die risiko-basierte prädiktive Planung von Inspektionen und Reparaturen von Ingenieurbauwerken gegeben. T2 - AISTEC 5. Verbundtreffen CY - Online meeting DA - 24.06.2021 KW - AISTEC KW - Structural Health Monitoring KW - Brücken PY - 2021 AN - OPUS4-52982 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Herrmann, Ralf T1 - AISTEC 5. Verbundtreffen - Messfahrt auf der Maintalbrücke Gemünden N2 - Der Vortrag stellt die Durchführung und die ersten Ergebnisse der Belastungsfahrten der BAM im Rahmen des AISTEC Projekts an der Maintalbrücke am 19.05. und 20.05.2021 vor. Es wurden Tragwerksreaktionen des Bauwerks mit dem installierten Dauermonitoringsystem und insbesondere dem Betongelenk mit zusätzlich installierter Sensorik aufgezeichnet. Für die Ermittlung der Lastposition wurden mehrere Verfahren eingesetzt und verglichen. T2 - AISTEC 5. Verbundtreffen CY - Online meeting DA - 24.06.2021 KW - AISTEC KW - Structural Health Monitoring KW - Einflusslinie KW - Messfahrt KW - Belastungszug PY - 2021 AN - OPUS4-52927 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Viefhues, Eva A1 - Döhler, M. A1 - Hille, Falk A1 - Mevel, L. T1 - Statistical subspace-based damage detection with estimated reference N2 - The statistical subspace-based damage detection technique has shown promising theoretical and practical results for vibration-based structural health monitoring. It evaluates a subspacebased residual function with efficient hypothesis testing tools, and has the ability of detecting small changes in chosen system parameters. In the residual function, a Hankel matrix of Output covariances estimated from test data is confronted to its left null space associated to a reference model. The hypothesis test takes into account the covariance of the residual for decision making. Ideally, the reference model is assumed to be perfectly known without any uncertainty, which is not a realistic assumption. In practice, the left null space is usually estimated from a reference data set to avoid model errors in the residual computation. Then, the associated uncertainties may be non-negligible, in particular when the available reference data is of limited length. In this paper, it is investigated how the statistical distribution of the residual is affected when the reference null space is estimated. The asymptotic residual distribution is derived, where its refined covariance term considers also the uncertainty related to the reference null space estimate. The associated damage detection test closes a theoretical gap for real-world applications and leads to increased robustness of the method in practice. The importance of including the estimation uncertainty of the reference null space is shown in a numerical study and on experimental data of a progressively damaged steel frame. KW - Damage detection KW - Uncertainty quantification KW - Statistical tests KW - Ambient excitation KW - Vibration measurement PY - 2022 DO - https://doi.org/10.1016/j.ymssp.2021.108241 SN - 0888-3270 VL - 164 SP - 108241 PB - Elsevier Ltd. AN - OPUS4-52998 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Viefhues, Eva A1 - Döhler, M. A1 - Simon, Patrick A1 - Herrmann, Ralf A1 - Hille, Falk A1 - Mevel, L. ED - Cunha, A. ED - Caetano, E. T1 - Stochastic subspace-based damage detection of a temperature affected beam structure N2 - Structural health monitoring (SHM) of civil structures often is limited due to changing environmental conditions, as those changes affect the structural dynamical properties in a similar way like damages can do. In this article, an approach for damage detection under changing temperatures is presentedand applied to a beam structure. The used stochastic subspace-based algorithm relies on a reference null space estimate, which is confronted to data from the testing state in a residual function. For damage detection the residual is evaluated by means of statistical hypothesis tests. Changes of the system due to temperature effects are handled with a model interpolation approach from linear parameter varying system theory. From vibration data measured in the undamaged state at some few reference temperatures, a model of the dynamic system valid for the current testing temperature is interpolated. The reference null space and the covariance matrix for the hypothesis test is computed from this interpolated model. This approach has been developed recently and was validated in an academic test case on simulations of a mass-spring-damper. In this paper, the approach is validated experimentally on a beam structure under varying temperature conditions in a climate chamber. Compared to other approaches, the interpolation approach leads to significantly less false positive alarms in the reference state when the structure is exposed to different temperatures, while faults can still be detected reliably. T2 - 10th International Conference on Structural Health Monitoring of Intelligent Infrastructure, SHMII 10 CY - Online meeting DA - 30.06.2021 KW - Damage detection KW - Subspace methods KW - Temperature effects KW - Model interpolation KW - Climate chamber KW - Laboratory beam structure PY - 2021 SP - 1 EP - 6 AN - OPUS4-52999 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Diercks, Philipp T1 - A variational multiscale method for heterogeneous structures N2 - In analyzing large scale structures, it is necessary to take into account the material heterogeneity for accurate failure prediction. However, this greatly increases the degrees of freedom in the numerical method making it infeasible. Moreover, in applications where scale separation as the basis of classical homogenization schemes does not hold, the influence of the fine scale on the coarse scale has to be modelled directly. This work aims to develop an efficient methodology to model heterogeneous structures combining the variational multiscale method and model order reduction techniques. Superposition based methods assume a split of the solution field into coarse and fine scale contributions. In deriving practical methods some form of localization is necessary to eliminate the fine scale part from the coarse scale equation. Hund and Ramm discussed different locality constraints and resulting solution procedures in the context of solid mechanics. Particularly, zero jump conditions ensuring continuity of the fine scale solution which are enforced by a Lagrange type method lead to a coupled solution procedure. In this contribution, a combination of the variational multiscale method and model order reduction techniques is applied to model the influence of the fine scale on the coarse scale directly. First, possible coarse and fine scale solutions are exploited for a representative volume element (RVE), specific to the material of interest, to construct local approximation spaces. The local spaces are designed such that local contributions of RVEs can be coupled in a conforming way. Therefore, the resulting global system takes the effect of the fine scale on the coarse scale into account, is sparse and reduced in size compared to the direct numerical simulation. The authors gratefully acknowledge financial support by the German Research Foundation (DFG), project number 394350870, and by the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation programme (ERC Grant agreement No. 818473). T2 - USNCCM16 CY - Berlin, Germany DA - 28.07.2021 KW - Multiscale methods KW - Variational multiscale method KW - Model order reduction PY - 2021 AN - OPUS4-53291 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Viefhues, Eva T1 - Stochastic subspace-based damage detection of a temperature affected beam structure N2 - Structural health monitoring (SHM) of civil structures often is limited due to changing environmental conditions, as those changes affect the structural dynamical properties in a similar way like damages can do. In this article, an approach for damage detection under changing temperatures is presentedand applied to a beam structure. The used stochastic subspace-based algorithm relies on a reference null space estimate, which is confronted to data from the testing state in a residual function. For damage detection the residual is evaluated by means of statistical hypothesis tests. Changes of the system due to temperature effects are handled with a model interpolation approach from linear parameter varying system theory. From vibration data measured in the undamaged state at some few reference temperatures, a model of the dynamic system valid for the current testing temperature is interpolated. The reference null space and the covariance matrix for the hypothesis test is computed from this interpolated model. This approach has been developed recently and was validated in an academic test case on simulations of a mass-spring-damper. In this paper, the approach is validated experimentally on a beam structure under varying temperature conditions in a climate chamber. Compared to other approaches, the interpolation approach leads to significantly less false positive alarms in the reference state when the structure is exposed to different temperatures, while faults can still be detected reliably T2 - 10th International Conference on Structural Health Monitoring of Intelligent Infrastructure, SHMII 10 CY - Online meeting DA - 30.06.2021 KW - Damage detection KW - Subspace methods KW - Temperature effects KW - Model interpolation KW - Climate chamber KW - Laboratory beam structure PY - 2021 AN - OPUS4-53000 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Unger, Jörg F. T1 - Stochastische Modellkalibrierung eines digitalen Zwillings N2 - Motivation: Ein Digitaler Zwilling repräsentiert ein reales Objekt in der digitalen Welt. Die Digitalen Zwillinge sind aus Daten und Modellen/Algorithmen aufgebaut und kontinuierlich über Sensoren mit der realen Welt gekoppelt. Anwendung z.B. Modellbewertung, Monitoring, Schadensdetektion. T2 - VIPO Symposium 2021 CY - Bauhaus-Universität Weimar DA - 09.07.2021 KW - Digitaler Zwilling KW - Modellkalibrierung KW - Modelanpassung KW - Bayesian Inferenz PY - 2021 AN - OPUS4-53063 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Weigel, Sandra A1 - Recknagel, Christoph T1 - FTIR-Charakterisierung von Bitumen - Möglichkeiten und Chancen N2 - Das erdölstammige Bindemittel Bitumen weist eine so komplexe Struktur auf, dass diese mit den derzeit eingesetzten Verfahren nur eingeschränkt erfasst werden kann. Eine innovative und vielversprechende Möglichkeit bietet in diesem Zusammenhang die FTIR-Spektroskopie in Kombination mit einer chemometrischen Auswertung, mit der schnell und einfach Aussagen über die Zusammensetzung sowie verschiedenste physikalische und chemische Eigenschaften von bitumenhaltigen Materialien möglich werden. KW - Bitumen KW - FTIR KW - Chemometrie KW - Multivariate Analysemethoden KW - Charakterisierung KW - Identifizierung von Additiven PY - 2021 SN - 1618-8357 SP - 42 EP - 49 PB - ALPHA Informationsgesellschaft mbH CY - Lampertheim AN - OPUS4-53486 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schwettmann, K. T1 - Post carbon road - The endless cycle of bitumen reuse N2 - In Germany, the reuse of asphalt has a long tradition. Since the 1980s, the reclaimed asphalt has been recycled achieving a reuse rate of around 90% and thus a very high value in the last years. In the future, instead of the amount, the quality of the reclaimed asphalt will be more important because the recycled asphalt will be reused again and again. Thus, these asphalt mixes are in the second or even third cycle of reuse. Concerning this situation, the question arises if asphalt can be reused several times without any loss in quality. An important factor affecting the asphalt quality is the binder bitumen. During the production, construction and service life, the ageing of this binder occurs causing a hardening of the bitumen. To compensate this hardening, additives for the reclaimed asphalt in terms of rejuvenation agents (rejuvenators) gain in importance. With these rejuvenators, the physical properties of bitumen can be modified e.g. the hardness and the stiffness reduced. However, the mechanism of the rejuvenation agents and the effects of the bitumen chemistry are largely unknown because the composition of the products varies very strongly. But with growing knowledge about these mechanisms and effects of the rejuvenation agents, the chemical composition and thus the physical and ageing behavior of bitumen can be targeted modified by the use of suitable rejuvenators. In this work, the actual results of the project Postcarbone road should be presented including investigations about the chemical and physical mechanisms as well as the efficiency of different rejuvenators. Further, a model for the cyclic reuse of bitumen should be developed. Based on this model, the choice of a suitable rejuvenation agent for the considered bitumen or rather asphalt should be possible. The project Postcarbone road (392670763) is funded by the German Research Foundation (DFG). T2 - 7th Eurasphalt and Eurobitume Congress CY - Online meeting DA - 15.06.2021 KW - Bitumen KW - Multiple ageing and rejuvenation KW - Conventional testing KW - DSR KW - BBR KW - FTIR KW - Asphaltene content KW - Column chromatography PY - 2021 AN - OPUS4-53489 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Rogge, Andreas T1 - Monitoring 4.0/5.0 N2 - Mehr als 10 % des deutschen Bruttoinlandsprodukts werden für Investitionen imBausektor eingesetzt. Die unmittelbar folgende Erkenntnis, dass eine zukunftsorientierte, nachhaltige Umgestaltung unserer Gesellschaft nicht ohne einen substanziellen Beitrag des Bausektors gelingen kann, hat sich mittlerweile weitgehend durchgesetzt. Die Komplexität der zugehörigen technischen Herausforderungen ist jedoch nicht zu unterschätzen. KW - Monitoring PY - 2021 DO - https://doi.org/10.1002/best.202170903 VL - 116 IS - 9 SP - 647 EP - 647 PB - Ernst & Sohn CY - Berlin AN - OPUS4-53361 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Gerist, S. A1 - R. Maheri, M. A1 - Unger, Jörg F. T1 - Damage Detection of a Scaled Steel Frame Offshore Structure Using an Improved Imperialist Competitive Algorithm N2 - In this paper, the imperialist competitive optimization algorithm is improved by damage functions to detect damage in a model steel frame test structure for offshore applications. A finite element model of the test structure is developed, validated and updated using the proposed method. As there are much more design variables, which are related to the stiffness of each finite element than the measured mode shapes, the problem is underdetermined. Therefore, damage functions are used to regularize the problem and decrease the number of design variables. A new objective function is proposed for the algorithm using the mode shapes and their l1 norm. The first ten measured mode shapes are used to solve the problem. It is shown that the proposed method is capable of predicting the damage locations with acceptable accuracy. KW - Damage detection KW - Imperialist competitive algorithm KW - Steel frames KW - Offshore structure KW - Damage functions PY - 2021 DO - https://doi.org/10.1007/s40996-021-00743-3 SN - 2228-6160 VL - 9 SP - 1 EP - 15 PB - Springer Verlag CY - Schweiz AN - OPUS4-53709 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rogge, Andreas T1 - Rückschlüsse aus dem Monitoring N2 - Wasserstoffinduzierte Spannungsrisskorrosion führt zu Standsicherheitsproblemen an Spannbetonbrückenbauwerken mit hochempfindlichen Spannstählen im Spannblockverfahren. An der Altstädter Brücke (Brandenburg a. d. H.) bot sich die Gelegenheit, kurz vor deren Rückbau umfangreiche Untersuchungen zur Detektion und Verifizierung dieses Schadensbildes durchzuführen und verschiedene Monitoringverfahren hinsichtlich ihrer Eignung für diese spezielle Fragestellung zu untersuchen. T2 - B1 - Brücke am Altstädter Bahnhof in Brandenburg an der Havel, Fachdiskussion zu den Ergebnissen der Bauwerksuntersuchungen CY - Potsdam, Germany DA - 06.10.2021 KW - Faseroptische Sensorik KW - Schallemissionsanalyse KW - Schwingungsmessung KW - SSDD-Verfahren KW - Dehnungsmessstreifen PY - 2021 AN - OPUS4-53736 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schneider, Ronald A1 - Rogge, Andreas A1 - Thöns, S. A1 - Bismut, E. A1 - Straub, D. ED - Caspeele, Robby ED - Taerwe, Luc ED - Frangopol, Dan M. T1 - A sampling-based approach to identifying optimal inspection and repair strategies for offshore jacket structures N2 - Identifying optimal inspection and repair strategies for offshore jacket structures is a challenging task. We pre-sent an approach, which is based on recent developments in the field of risk-based operation and maintenance planning at the structural system level. The approach utilizes heuristics to define inspection and repair strate-gies at the system level and to reduce the search space of possible strategies. For each defined strategy, the expected service life cost of inspection, repair and failure is evaluated based on simulated inspection and re-pair histories. Subset simulation is applied to compute the conditional repair and failure probabilities required for this analysis. It also forms the basis for simulating inspection and repair histories. The strategy that mini-mizes the expected service life cost is the optimal one in the set of pre-selected strategies. The underlying condition and performance model accounts for the stochastic dependence among the deterioration states of the different structural elements and the structural redundancy. The approach is demonstrated in a case study considering a jacket-type frame. In this study, we essentially vary the inspection interval, the minimum num-ber of inspected components and the target reliability, and identify the combination that minimizes the ex-pected total service life cost. T2 - The sixth international symposium on life-cycle civil engineering (IALCCE 2018) CY - Ghent, Belgien DA - 28.10.2018 KW - Offshore steel structures KW - Fatigue KW - Reliability KW - Risk KW - Inspection planning PY - 2019 SN - 978-1-138-62633-1 SN - 978-1-315-22891-4 SP - 1081 EP - 1088 PB - Taylor & Francis Group CY - London AN - OPUS4-46434 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Pirskawetz, Stephan A1 - Hüsken, Götz A1 - Gründer, Klaus-Peter A1 - Kadoke, Daniel ED - Caspeele, R. ED - Taerwe, L. ED - Frangopol, D. M. T1 - Damage mechanisms analysis of reinforced concrete beams in bending using non-destructive testing N2 - Beams that are loaded in transverse direction are one of the main structural elements used in reinforced concrete structures. Bending beams are used, for example, in bridge girders or joists. The strength related failure modes at maximum loading can be divided into bending and shear failure that could occur with or without indication. Conventional design concepts used in practice for designing structural elements subjected to bending aim at failure modes with sufficient indication (e.g. large deflections or cracks), as it occurs in the case of secondary flexure-compression-failure. These indicators can also be used to identify structural changes of civil infrastructure systems (e.g. bridges) using non-destructive testing methods for Structural Health Monitoring (SHM). However, profound knowledge on the determining failure modes of bending beams is required for the reliable application of structural health monitoring. Therefore, resulting effects of different thermal and mechanical loads on the response of a structure are investigated by means of a bridge demonstrator. The results of this investigation are used for developing a monitoring system. Different non-destructive testing (NDT) methods have been used for analyzing the deformation behavior of a reinforced concrete beam in bending. The suitability of the different measuring techniques will be discussed by means of the obtained experimental results. For this purpose, the deformation behavior of a reinforced concrete beam having a span of 2.75 m was investigated in a four-point bending flexural test at laboratory scale. The focus is on the characterization of determining failure modes by the NDT methods and the comparison with classical measuring techniques (e.g. deformation measurements by displacement transducers). The bending tests have been accompanied by Acoustic Emission analysis (AE), optical deformation measurements using Stereophotogrammetry (SP) and Digital Image Correlation (DIC). The conducted tests have shown that the three-dimensional detection of deformations and resulting strains with optical techniques is beneficial for analyzing the damage mechanism of loaded structures and related crack formation and propagation. Optical techniques can be supplemented by acoustic emission testing which gives detailed information on crack formation and progressing damage. The combination of both techniques offers the application as efficient monitoring system for larger structures. T2 - Sixth International Symposium on Life-Cycle Civil Engineering (IALCCE 2018) CY - Ghent, Belgium DA - 28.10.2018 KW - Concrete Beam KW - Bending KW - Digital Image Correlation KW - Stereophotogrammetry KW - Acoustic Emission Analysis KW - Non-Destructive Testing PY - 2019 SN - 978-1-138-62633-1 SN - 978-1-315-22891-4 SP - 2411 EP - 2417 PB - CRC Press AN - OPUS4-46439 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Simon, Patrick A1 - Schneider, Ronald A1 - Baeßler, Matthias A1 - Recknagel, Christoph ED - Cunha, Á. ED - Caetano, E. T1 - Enhancing structural models with material tests and static response data - a case study considering a steel beam with asphalt layer subject to temperature variations N2 - Gradual or sudden changes in the state of structural systems caused, for example, by deterioration or accidental load events can influence their load-bearing capacity. Structural changes can be inferred from static and/or dynamic response data measured by structural health monitoring systems. However, they may be masked by variations in the structural response due to varying environmental conditions. Particularly, the interaction of nominally load-bearing components with nominally non-load bearing components exhibiting characteristics that vary as a function of the environmental conditions can significantly affect the monitored structural response. Ignoring these effects may hamper an inference of structural changes from the monitoring data. To address this issue, we adopt a probabilistic model-based framework as a basis for developing digital twins of structural systems that enable a prediction of the structural behavior under varying ambient condition. Within this framework, different types of data obtained from real the structural system can be applied to update the digital twin of the structural system using Bayesian methods and thus enhance predictions of the structural behavior. In this contribution, we implement the framework to develop a digital twin of a simply supported steel beam with an asphalt layer. It is formulated such that it can predict the static response of the beam in function of its temperature. In a climate chamber, the beam was subject to varying temperatures and its static response wass monitored. In addition, tests are performed to determine the temperature-dependent properties of the asphalt material. Bayesian system identification is applied to enhance the predictive capabilities of the digital twin based on the observed data. T2 - International Conference on Structural Health Monitoring of Intelligent Infrastructure (SHMII-10) CY - Online meeting DA - 30.06.2021 KW - Digital twin KW - Structural health monitoring KW - Material tests KW - Bayesian updating PY - 2021 SN - 2564-3738 SP - 1537 EP - 1544 AN - OPUS4-54126 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Titscher, Thomas A1 - Unger, Jörg F. A1 - Oliver, J. T1 - Implicit explicit integration of gradient enhanced damage models N2 - Quasi-brittle materials exhibit strain softening. Their modeling requires regularized constitutive formulations to avoid instabilities on the material level. A commonly used model is the implicit gradient-enhanced damage model. For complex geometries, it still Shows structural instabilities when integrated with classical backward Euler schemes. An alternative is the implicit–explicit (IMPL-EX) Integration scheme. It consists of the extrapolation of internal variables followed by an implicit calculation of the solution fields. The solution procedure for the nonlinear gradient-enhanced damage model is thus transformed into a sequence of problems that are algorithmically linear in every time step. Therefore, they require one single Newton–Raphson iteration per time step to converge. This provides both additional robustness and computational acceleration. The introduced extrapolation error is controlled by adaptive time-stepping schemes. This paper introduced and assessed two novel classes of error control schemes that provide further Performance improvements. In a three-dimensional compression test for a mesoscale model of concrete, the presented scheme was about 40 times faster than an adaptive backward Euler time integration. KW - Implicit explicit schemes KW - Gradient-enhanced damage model KW - Adaptive time stepping KW - Continuum damage KW - Robustness PY - 2019 DO - https://doi.org/10.1061/(ASCE)EM.1943-7889.0001608 SN - 0733-9399 SN - 1943-7889 VL - 145 IS - 7 SP - 04019040-1 EP - 04019040-13 PB - ASCE - American Society of Civil Engineers AN - OPUS4-48361 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bhuyan, Md Delwar Hossain A1 - Le Touz, N. A1 - Gautier, G. A1 - Döhler, M. A1 - Hille, Falk A1 - Dumoulin, J. A1 - Mevel, L. T1 - Load vector based damage localization with rejection of the temperature effect N2 - The Stochastic Dynamic Damage Locating Vector (SDDLV) approach is a vibration-based damage localization method based on both a finite element model of a structure and modal parameters estimated from output-only measurements in the damage and reference states. A statistical version of the Approach takes into account the inherent uncertainty due to noisy measurement data. In this paper, the effect of temperature fluctuations on the performance of the method is analyzed in a model-based approach using a finite element model with temperature dependent parameters. Robust damage localization is carried out by rejecting the temperature influence on the identified modal parameters in the damaged state. The algorithm is illustrated on a simulated structure. T2 - 8. International Operational Modal Analysis Conference CY - Kopenhagen, Denmark DA - 12. Mai 2019 KW - SDDLV KW - Load vector KW - Temperature rejection KW - Statistical evaluation PY - 2019 SP - 1 EP - 10 AN - OPUS4-48182 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bhuyan, Md Delwar Hossain A1 - Döhler, M. A1 - Lecieux, Y. A1 - Lupi, C. A1 - Thomas, J.-C. A1 - Schoefs, F. A1 - Hille, Falk A1 - Mevel, L. T1 - Statistical subspace based damage localization on Saint-Nazaire bridge mock-up N2 - The subject of damage localization is an important issue for Structural Health Monitoring (SHM) particularly in mechanical or civil structures under ambient excitation. In this paper, the statistical subspacebased damage localization method has been applied on a benchmark application, namely a 1/200 scale model of the Saint-Nazaire Bridge, which is a cable-stayed bridge located on the Loire River near the river’s mouth. The employed damage localization method combines data-driven features with physical parameter information from a finite element model in statistical tests, avoiding typical ill-conditioning problems of FE model updating. Damage is introduced in the mockup for cable failures on some of the 72 cables. The purpose of the experiment is to assess the capability of damage assessment methods to find a cable failure. T2 - 8. International Operational Modal Analysis Conference CY - Kopenhagen, Denmark DA - 12. Mai 2019 KW - Damage localization KW - Cable-stayed bridge KW - Cable failure KW - Structural health monitoring PY - 2019 SP - 1 EP - 9 AN - OPUS4-48183 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Unger, Jörg F. T1 - Combination of model reduction and adaptive subset simulation for structural reliability problems N2 - A safe and robust design is a key criterion when building a structure or a component. Ensuring this criterion can either be performed by fullfilling prescribed safety margins, or by using a full probabilistic approach with a computation of the failure probability. The latter approach is particularly well suited for complex Problems with an interaction of different physical penomena that can be described in a numerical model. The bottleneck in this approach is the computational effort. Sampling methods such as Markov chain Monte Carlo methods are often used to evaluate the system reliability. Due to small failure probabilities (e.g. 10^6) and complex physical models with already and extensive computational effort for a single set of parameters, these methods a prohibitively expensive. The focus of this contribution is to demonstrate the advantages of combining model reduction techniques within the concept a variance reducing adaptive sampling procedures. In the developed method, a modification of the adaptive subset simulation based on Papaioannou et al. 2015 is used and coupled with a limit state function based on Proper Generalized Decomposition (PGD) (Chinesta et al. 2011). In the subset simulation the failure probability is expressed as a product of larger conditional failure probabilities. The intermediate failure events are chosen as a decreasing sequence. Instead of solving each conditional probability with a Markov chain approach, an importance sampling approach is used. It is be shown that the accuracy of the estimation depends mainly on the number of samples in the last sub-problem. For model reduction, the PGD approach is used to solve the structural problem a priori for a given Parameter space (physical space plus all random parameters). The PGD approach results in an approximation of the problem output within a prescribed range of all input Parameters (load factor, material properties, ..). The approximation of the solution by a separated form allows an evaluation of the limit state function within the sampling algorithm with almost no cost. This coupled PGD – adaptive subset Simulation approach is used to estimate the failure probability of examples with different complexity. The convergence, the error propagation as well as the reduction in computational time is discussed. T2 - UNCECOMP 3rd International Conference on Uncertainty Quantification in Computational Sciences and Engineering CY - Crete, Greece DA - 26.06.2019 KW - Model reduction KW - Reliability analysis KW - Simulation KW - Finite Elemente Method (FEM) KW - Proper Generalized Decomposition (PGD) PY - 2019 AN - OPUS4-48479 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Coelho Lima, Isabela T1 - Identification of model deficiencies in model parameter calibration N2 - Accurate and reliable assessment of transportation infrastructures (e.g. bridges) are crucial for ensuring public safety. Simulation-based engineering analyses can be used to assess and predict the health state of structures. Although some of the structural parameters necessary for such simulations cannot be directly measured, they can be inferred from Non-Destructive Testing data, in a typical inverse problem formulation. However, any prediction based on engineering models will never be an exact representation of reality, since many sources of uncertainties can be present: poor physical representation of the problem (model bias); measurement errors; uncertainty on inferred parameters; etc. Uncertainty quantification is, therefore, of utmost importance to ensure reliability of any decision based on the simulations. This paper investigates the application of the Modular Bayesian framework to perform structural parameter calibration while estimating a function for the model bias. The data for tests comes from an experimental setup and is represented as a combination of a physics-based model, a model bias term and an additive measurement error (considered to be known). In this approach, the inference problem is divided into 3 modules: the first and the second estimate the optimal hyper-parameters of Gaussian Processes (GP) to replace the physics-based and the model bias term, respectively; the third computes the posterior distribution of the structural parameters of interest, taking into account the GPs from the previous modules. By computing a bias-correction function and calibrating the parameters, the modular framework aims at improving the accuracy of the predictions. T2 - UNCECOMP 2019 CY - Crete, Greece DA - 24.06.2019 KW - Model Bias KW - Uncertainty quantification KW - Modular Bayesian KW - Structural Model Calibration PY - 2019 AN - OPUS4-48575 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Robens-Radermacher, Annika T1 - Efficient reliability analysis coupling important sampling using adaptive subset simulation and PGD model reduction N2 - The key point of structural reliability analysis is the estimation of the failure probability (Pf), typically a rare event. This probability is defined as the integral over the failure domain which is given by a limit state function. Usually, this function is only implicit given by an underlying finite element simulation of the structure. It is generally not possible to solve the integral for Pf analytically. For that reason, simulation-based methods as well as methods based on surrogate modeling (or Response surface methods) has been developed. Nevertheless, these variance reducing methods still require a few thousand calculations of the underlying finite element model, making reliability Analysis computationally expensive for real applications. T2 - GAMM - Gesellschaft für Angewandte Mathematik und Mechanik e.V. CY - Vienna, Austria DA - 18.02.2019 KW - PGD model reduction PY - 2019 AN - OPUS4-48628 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Müller, Philipp T1 - Waves in inhomogeneous meshes N2 - Elastic waves in inhomogeneous meshes avoiding numerical artifacts Elastic waves in solids resulting from damage processes, e.g. microcracking are used to monitor the integrity of structures. The numerical modelling of these acoustic Emission processes is hindered by the different scales involved. Crack opening is a fast process and the size of the damaged zone is small, leading to small time steps and fine meshes in a numerical finite element simulation. On the other hand the relevant wave Propagation takes place on a much larger spatial scale, e.g covering the distance between Emission source and sensor. To avoid numerical oscillations, the mesh size at the emission source has to be coupled to its time scale. Using higher order spectral elements can be beneficial with respect to the needed number of degrees of freedom. To make the computation of an acoustic emission process feasible one is lead to coarsening the mesh for larger distances to the source. Solution components with a higher frequency will be reflected at mesh density steps. The mesh coarsening has to be done in a way to avoid or minimize this kind of reflections. To get more insight into the propagation characteristics of the numerical solution, dispersion curves are calculated for different element types assuming a structured mesh with constant element size. Coupling two meshes with different mesh densities will then lead to frequency dependent reflections at the boundary similar to the coupling of different materials. The starting mesh density is dictated by the acoustic emission source time scale. The largest allowable mesh size needs to resolve the components of propagating signal with the highest frequency, smallest wavelength which is given by the bandwidth of the sensor. Still coarser meshes may be used when high frequency components are propagated by a different method. T2 - COMPDYN 2019 CY - Crete, Greece DA - 24.06.2019 KW - FEM KW - Waves KW - Dispersion PY - 2019 AN - OPUS4-48582 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Pohl, Christoph T1 - Pore water state in heated concrete N2 - Spalling of concrete structures is a serious issue for their safety. A better understanding of the pore water distribution and state during a fire is a prerequisite for numerical approaches to such problems. Temperature-driven water transport in concrete consists of multiple phenomena, such as convection, diffusion, adsorption and dehydration. Distinguishing the different influences experimentally is difficult because typically they cannot be disentangled. A common experimental setup approximates a one-dimensional flow, and places temperature and pressure gauges along the propagation direction. For direct information about the water content inside a sample, methods such as NMR or neuron radiography are necessary. A multiphase model for the flow in porous media is presented, with dehydration and changes in the pore size distribution taken into consideration. NMR measurements for temperature-driven flow have been performed. The numerical and experimental results are compared for water transport at temperatures below the critical point. Since both the finite-element model and the experiment allow the distinction between adsorbed, capillary and bulk water, a more fine-grained view of the pore water state is obtained. T2 - CM4P - Computational methods in multi-scale, multi-uncertainty and multi-physics problems CY - Porto, Portugal DA - 15.07.2019 KW - Spalling KW - Porous media KW - Multiphase flow KW - Finite element method PY - 2019 AN - OPUS4-48707 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bhuyan, Md Delwar Hossain A1 - Gautier, G. A1 - Le Touz, N. A1 - Döhler, M. A1 - Hille, Falk A1 - Dumoulin, J. A1 - Mevel, L. T1 - Vibration‐based damage localization with load vectors under temperature changes N2 - Damage detection and localization in civil or mechanical structures is a subject of active development and research. A few vibration‐based methods have been developed so far, requiring, for example, modal parameter estimates in the reference and damaged states of the investigated structure, and for localization in addition a finite element model. For structures in operation, temperature has been shown to be a major nuisance to the efficiency of such methods because the modal parameters are varying not only with damage but also due to temperature variations. For detection, a few rejection approaches have been developed. Besides the increased complexity, environmental variation is hardly taken into account in localization approaches. In this paper, we propose a sensitivity‐based correction of the identified modal parameters in the damaged state with respect to the temperature field in the reference state, on the basis of a sensitivity analysis with respect to temperature dependent Parameters of the finite element model in the reference state. The approach is then applied to the stochastic dynamic damage locating vector method, where its improved performance under nonuniform temperature variations is shown in a numerical application on a beam. KW - Statistical evaluation KW - Damage localization KW - Load vector KW - Temperature effect rejection KW - Temperature modeling PY - 2019 DO - https://doi.org/10.1002/stc.2439 SN - 1545-2255 SN - 1545-2263 SP - e2439, 1 EP - 16 PB - John Wiley & Sons, Ltd. AN - OPUS4-48843 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Diercks, Philipp T1 - A hyper reduced domain decomposition approach for modeling nonlinear heterogeneous structures N2 - Many of today's problems in engineering demand reliable and accurate prediction of failure mechanisms of mechanical structures. Herein it is necessary to take into account the often heterogeneous structure on the fine scale, to capture the underlying physical phenomena. However, an increase of accuracy by dissolving the fine scale inevitably leads to an increase in computational cost. In the context of multiscale simulations, the FE2 method is widely used. In a two-level computation, the fine scale is depicted by a boundary value problem for a representative volume element (RVE), which is then solved in each integration point of the macro scale to determine the macroscopic response. However, the FE2 approach in general is computationally expensive and problematic in the special case of concrete structures. Here rather large RVEs are necessary to sufficiently represent the meso-structure, such that separation of scales cannot be assumed. Therefore, the aim is to develop an efficient approach to modeling nonlinear heterogeneous structures using domain decomposition and reduced order modeling. T2 - ECCOMAS Young Investigators Conference 2019 CY - Krakow, Poland DA - 01.09.2019 KW - Model order reduction KW - Proper orthogonal decomposition KW - Discrete empirical interpolation method KW - Multiscale KW - Domain Decomposition PY - 2019 AN - OPUS4-48942 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hüsken, Götz T1 - Comparison of cracks formed in scaled grouted connection of offshore energy structures under static and cyclic loads N2 - Global energy consumption will increase in the future necessitating both fossil fuels and renewable energy choices - especially wind energy. Such high energy demand requires installation of offshore energy structures, rigs, platforms and towers, which are susceptible to adverse environmental conditions along with maintenances. Due to their large size and remote locations, cylindrical grouted joints are often adopted between substructure and foundation in these offshore platforms and wind structures such as monopiles. However, these connections are composite structures with exterior sleeve, interior pile and infill mortar. Degradation and settlements were reported inside similar connections, which were installed in last three decades. Besides, grouting in the offshore sites were proven difficult to obtain ideal load bearing capacity. In-situ loading conditions were also found to be affecting the failure mechanism inside such connections. This study aims at characterizing the nature of cracks generated in these grouted connections under both static and cyclic loading. Scaled grouted joints were manufactured using a novel reusable mold, and connections were loaded to failure to visualize the main failure patterns. An assessment between failure under these two types of load is drawn along with comparison to previously available literature. T2 - 5th International Conference on Smart Monitoring, Assessment and Rehabilitation of Civil Structures CY - Potsdam, Germany DA - 27.08.2019 KW - Grouted connection KW - Crack formation KW - Crack pattern KW - Static load KW - Cyclic load PY - 2019 AN - OPUS4-48797 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Thiele, Marc T1 - Comparison of fatigue crack detection methods for high-cyclic loaded steel structures N2 - At present, to produce renewable energy offshore wind farms play an important role. The available space combined with the more valuable wind conditions make offshore locations very attractive for wind powered energy production. In Europe a significant number of offshore wind farms already exist, especially in the North and Baltic Sea. In future this trend will continue, and further offshore wind farms will be built. The majority of offshore wind turbines are mounted on steel foundation structures. Due to the high-cyclic loading by wind and waves fatigue stress plays a substantial role regarding structural safety. Besides the consideration of fatigue within the design process, to monitor existing steel structures for potential fatigue cracks during their life time is a major topic and a challenge. For the structures of the offshore wind turbines are large and partially under water effective reliable methods for the detection of fatigue cracks are required. This contribution presents investigations on different crack detection methods applied at high-cycle fatigue tests on small-scale welded steel samples as well as on large-scale welded steel components. The tests were conducted at the BAM laboratories. For crack detection mainly three different methods were used and compared. The first method regards to the measurement of strain by conventionally strain gauges. Secondly, the crack luminescence was used as a new and effective optical method for surface monitoring. And finally, crack detection by pressure differentials of the inner and outer section of tubular steel elements was investigated. A comparison study will emphasize the advantages and disadvantages of the different methods and show which of the described methods is potentially more suitable for an application on real offshore wind structures. T2 - 5th International Conference on Smart Monitoring, Assessment and Rehabilitation of Civil Structures CY - Potsdam, Germany DA - 27.08.2019 KW - Fatigue KW - Steel structures KW - Crack detection PY - 2019 AN - OPUS4-48944 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Thibaux, Philippe A1 - Van Wittenberghe, Jeroen A1 - Fricke, Wolfgang A1 - Thiele, Marc A1 - Nielsen, Lars Peter A1 - Conti, Fabien T1 - Results of the JaCo project: fatigue strength of robot‑welded tubular joints for offshore wind energy converters N2 - Jacket foundations requires the welding of a large number of tubular joints. These foundations type is suitable to support wind energy converters in deeper water. In order to increase the production speed and its quality, robot systems were developed to produce tubular joints. Since fatigue is dominating the design of these structures, an assessment of the performance of tubular joints produced by robots was performed and compared with the performance of manually welded joints. 18 large-scale tests were performed on joints with dimensions representative for offshore structures, which were produced in industrial environment. Breakthrough cracks occurred through the chord, with cracks initiated at the weld toe, although in some cases cracks were also initiated between weld beads. The measured fatigue strengths of joints produced by robot were similar or higher than the T-curve of DNV-RP-C203. Some delivered components showed fatigue strength that was more than 20% higher than the standard curve. These results emphasize that mastering the welding process with robots is necessary to achieve superior levels of fatigue strength. KW - Fatigue KW - Tubular joint KW - Robot welding KW - Hot spot method KW - Large-scale testing PY - 2024 DO - https://doi.org/10.1007/s40194-024-01903-5 SN - 1878-6669 SP - 1 EP - 14 PB - Springer CY - Berlin ; Heidelberg AN - OPUS4-62319 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Baeßler, Matthias T1 - Dynamisches Verhalten und Überwachung des Großen Fallturms der BAM in Horstwalde N2 - Falltürme sind Bauwerke, die als Versuchsanlagen sehr speziellen, impulsartigen Belastungen ausgesetzt sind. Am Fallturm auf dem Testgelände Technische Sicherheit (TTS) der BAM wurde bei Routineinspektionen eine Abnahme der strukturellen Integrität in Form von Vorspannungsverlusten in den Bolzen der Stahlverbindungen festgestellt. Um ein Verständnis für die zugrundeliegenden Trag- und Schädigungsmechanismen zu erlangen, wurde ein umfassendes Structural Health Monitoring (SHM) System geplant und am Bauwerk installiert unter Nutzung von digitalen Bauwerksmodellen. Für die Auslegung des Überwachungssystems, insbesondere aber zur Unterstützung der Untersuchung des Schädigungsprozesses, wurden Finite-Elemente-Modelle erstellt. Um sicherzustellen, dass die FE-Modelle das reale Tragwerksverhalten mit ausreichender Genauigkeit abbilden, mussten sie jedoch in Bezug auf die gemessenen Antworten des Tragwerks kalibriert werden. Der vorliegende Beitrag beschreibt experimentelle und numerische Untersuchungen zur Identifizierung des strukturellen Systems des Stahlrohrgitterturms in Vorbereitung einer Überwachungskampagne. Die Auswertung von gemessenen Schwingungen unter ambienter Anregung ermöglichte die Identifizierung der Eigenfrequenzen mehrerer globaler Schwingungsmoden des Fallturms. Zur Modellvalidierung wurde zunächst eine Sensitivitätsanalyse durchgeführt, um die Parameter mit dem größten Einfluss zu ermitteln. Anschließend wurde ein evolutionärer Algorithmus (EA) zur Optimierung nach dem Prinzip der Minimierung der Differenzen zwischen gemessenen und simulierten charakteristischen Antworten eingesetzt. Das aktualisierte Modell wurde schließlich an der dynamischen Reaktion der Turmstruktur infolge einer realen Falltest-induzierten Stoßbelastung validiert. Die Ergebnisse zeigten eine gute Übereinstimmung zwischen numerischen und experimentellen Ergebnissen. N2 - Drop test towers are structures subjected to very specific dynamic loadings. At the drop test tower at the Test Site Technical Safety (TTS) of BAM routine inspections revealed a decline of structural integrity in form of loss of pretension in bolts of structural steel connections. To get an understanding about the underlying damage mechanisms as well as to assure the structural safety in operation, a multifaceted Structural Health Monitoring (SHM) system was planned and installed at the structure with the help of digital models. For planning the monitoring system but especially for supporting the investigation of the damaging process finite element models are deployed. Though, to ensure the capability of the FE model to reproduce the real structural behavior in sufficient accuracy, it needs to be calibrated in respect to measured responses of the structure. The present contribution describes experimental and numerical investigations to identify the structural system of the steel tube lattice tower in preparation of the monitoring campaign. An ambient vibration test allowed the identification of the natural frequencies of several global vibrational modes of the drop test tower. For model updating first a sensitivity analysis is applied to identify the most influencing parameter. In succession a genetic algorithm was applied for optimization in the sense of minimization of the difference between measured and simulated characteristic responses. The updated model is finally validated on the dynamic response of the tower structure to a real drop test induced impact loading. The results showed a good agreement between numerical and experimental results though the robustness of the simulation should be improved by more sophisticated numerical modelling. T2 - 7. VDI-Fachtagung Baudynamik CY - Würzburg, Germany DA - 27.04.2022 KW - Großer Fallturm Horstwalde KW - Structural Health Monitoring KW - Belastungsversuch KW - Modalanalyse KW - Schwingungsdynamik KW - Finite Elemente Simulation PY - 2022 AN - OPUS4-55470 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bos, Freek A1 - Menna, Constantino A1 - Robens-Radermacher, Annika A1 - Wolfs, Rob A1 - Roussel, Nicolas A1 - Lombois-Burger, Hélène A1 - Baz, Bilal A1 - Weger, Daniel A1 - Nematollahi, Behzad A1 - Santhanam, Manu A1 - Zhang, Yamei A1 - Bhattacherjee, Shantanu A1 - Jia, Zijian A1 - Chen, Yu A1 - Mechtcherine, Viktor T1 - Mechanical properties of 3D printed concrete: a RILEM TC 304-ADC interlaboratory study — approach and main results N2 - To show compliance to structural engineering codes and implement quality control measures, it is critical to obtain reliable mechanical properties of the materials in question. For conventional cast and precast concrete, the experimental procedures and relationships between mechanical properties, the material composition, and the production methods are globally known, but for 3D concrete printing (3DCP), these relations have not yet been established. Previous studies have shown little consistency in results, and the underlying experimental methods have not been established broadly. There is an urgent need to address these issues as the application of 3DCP in practice projects is growing rapidly. Therefore, RILEM TC 304-ADC: Assessment of Additively Manufactured Concrete Materials and Structures has set up a large interlaboratory study into the mechanical properties of 3D printed concrete. This paper presents key elements of the experimental approach detailed in the Study Plan and the supporting considerations. Furthermore, it reports on the response, consisting of 34 contributions from 30 laboratories, detailing global coverage, properties of the applied mixture designs and characteristics of the printing facilities that have been used. Subsequently, some fundamental results from compression, flexural, and E-modulus testing are presented and—considering cast specimens as a reference—discussed. On average, a reduction in strength was found in compression and E-modulus (all tested orientations). For flexure, on the other hand, an increase was found in two testing orientations, while a decrease was observed in the third orientation. Importantly, even though the applied experimental methods were found to be reasonably appropriate to obtain the required data, the differences found between individual contributions are significant and sometimes non-consistent, suggesting that testing on specific material-facility combinations is necessary to reliably determine the mechanical properties of objects produced from them. Furthermore, a theoretical framework needs to be developed to further explain the variations that were observed. Extensive analyses of all acquired data are out of the scope of this contribution, but presented in two associated papers, whereas a third presents the data management approach used to process the approximately 5,000 test results. KW - 3D printed concrete KW - 3DCP KW - Mechanical properties KW - Interlaboratory study PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-634631 DO - https://doi.org/10.1617/s11527-025-02686-x VL - 58 IS - 5 SP - 1 EP - 29 PB - Springer Nature AN - OPUS4-63463 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Cunningham, Patrick A1 - Mezhov, Alexander A1 - Schmidt, Wolfram T1 - Revealing Value from Bioderived Polymers: Effects of Locally Sourced Polysaccharides on the Rheology of Limestone Mixtures N2 - Admixtures are important constituents to enhance the performance of concrete. They allow for more efficient use of binders which can mitigate negative environmental impacts from producing cement-based materials. Commonly used rheology modifying agents like polycarboxylate ethers or cellulose ethers are synthetic or semi-synthetic, respectively. This requires additional energy consumption for their production and global supply chains particularly for many developing regions, which will be large consumers of concrete in the future. However, many locally available bio-based polysaccharides could be effectively used instead. These polymers are often overlooked by engineers and scientists due to their limited distribution and inherent complexity, yet they represent an underleveraged source of precursors for admixtures. This study investigates the action mechanisms of some bio-based rheology modifying agents, i.e., acacia gum and miscanthus gum, and provides a comparison to a conventionally modified starch. The results show that the mechanism of action of these polymers is closely related to the composition of the mixture, mixing regime, and the composition of the aqueous phase. Depending on the agent, either plasticizing or stabilizing effects on rheology can be revealed. T2 - ICBBM: International Conference on Bio-Based Building Materials CY - Vienna, Austria DA - 21.06.2023 KW - Polysaccharides KW - Superplasticizers KW - Hydration KW - Cement PY - 2023 DO - https://doi.org/10.1007/978-3-031-33465-8_60 SN - 2211-0852 VL - 45 SP - 782 EP - 792 PB - Springer Nature Switzerland AG CY - Switzerland AN - OPUS4-58726 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Mezhov, Alexander A1 - Robens-Radermacher, Annika ED - Mezhov, Alexander ED - Robens-Radermacher, Annika ED - Zhang, Kun ED - Kühne, Hans-Carsten ED - Unger, Jörg F. ED - Schmidt, Wolfram T1 - Temperature Impact on the Structural Build-Up of Cementitious Materials - Experimental and Modelling Study N2 - With increasing focus on industrialized processing, investigating, understanding, and modelling the structural build-up of cementitious materials becomes more important. The structural build-up governs the key property of fresh printable materials -- buildability -- and it influences the mechanical properties after the deposition. The structural build-up rate can be adjusted by optimization of the mixture composition and the use of concrete admixtures. Additionally, it is known, that the environmental conditions, i.e. humidity and temperature have a significant impact on the kinetic of cement hydration and the resulting hardened properties, such as shrinkage, cracking resistance etc. In this study, small amplitude oscillatory shear (SAOS) tests are applied to examine the structural build-up rate of cement paste subject to different temperatures under controlled humidity. The results indicate significant influences of the ambient temperature on the intensity of the re-flocculation (Rthix) rate, while the structuration rate (Athix) is almost not affected. A bi-linear thixotropy model extended by temperature dependent parameters coupled with a linear viscoelastic material model is proposed to simulate the mechanical behaviour considering the structural build-up during the SAOS test T2 - Third RILEM International Conference on Concrete and Digital Fabrication (Digital Concrete 2022) CY - Loughborough, UK DA - 27.06.2022 KW - Structural build-up KW - Rheological properties KW - Modelling PY - 2022 SN - 978-3-031-06116-5 DO - https://doi.org/10.1007/978-3-031-06116-5_49 VL - 37 SP - 330 EP - 336 PB - Springer International Publishing CY - Cham AN - OPUS4-55580 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Seifert, Lando A1 - Grunewald, Andreas A1 - Müller, Thoralf A1 - Ebell, Gino T1 - Stress corrosion tests for prestressing steels—Part 1: The influence of surface condition and test solution composition on hydrogen charging N2 - Tests for assessing prestressing steels' susceptibility to hydrogen‐induced stress corrosion cracking are essential for approvals, in‐house monitoring, and third‐party material testing. According to ISO 15630‐3, the time to brittle fracture by constant load under corrosive conditions in thiocyanate test solutions (A or B) at 50°C is measured. In the literature, a high scattering in stress corrosion tests is reported, which questions the integrity of the test procedure. This paper shows the results of studies about the influence of solution composition on hydrogen charging in electrochemical and permeation measurements. Electrochemical experiments show that polished steel surfaces without common drawing layers have more consistent free corrosion currents, polarization resistances, and B‐values in solution A with low scattering compared to the solution B experiments. The influence of temperature at 50°C and an ambient temperature of 22°C was also tested. KW - Drawing layers KW - Hydrogen‐induced stress corrosion cracking KW - Permeation measurements KW - Prestressing steels KW - Stress corrosion tests KW - Surface conditions KW - Test solutions PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-598738 DO - https://doi.org/10.1002/maco.202313948 VL - 75 SP - 1506 EP - 1518 PB - Wiley‐VCH GmbH AN - OPUS4-59873 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Rübner, Katrin A1 - Seher, Julia A1 - Müller, Constanze A1 - Müller, Anette A1 - Liebezeit, Steffen A1 - Schnell, Alexander A1 - Martin, Falk ED - Schermer, Detleff ED - Brehm, Eric T1 - REALight - Leichtgranulate und REA-Gips aus feinkörnigen sulfatbelasteten Bau- und Abbruchabfällen und industriellen Nebenprodukten N2 - Die Zielstellung des Forschungsprojekts REALight ist die Entwicklung eines Verfahrens zur Herstellung von Leichtgranulaten auf der Grundlage der Ergebnisse des BMBF-Projekts „Aufbaukörnungen“ unter Erweiterung der Technologie, um Gips zurückzugewinnen und weitere mineralische Einsatzstoffe zu nutzen. In einem thermischen Verfahren werden mineralische Bau- und Abbruchabfälle über ein rohstoffliches Recycling, d. h. einen thermisch-chemischen Stoffumwandlungsprozess, zu leichten Gesteinskörnungen verarbeitet. Dabei werden im Bauschutt vorhandene Sulfate zersetzt. In einer anschließenden Rauchgaswäsche werden die Sulfate abgetrennt. Sie können als Ersatz für REA-Gips verwendet werden. Dies ist Voraussetzung für die Übertragung der Produkt- und Verfahrensidee in die Praxis und für den Nachweis der Sulfatabtrennung und -rückgewinnung aus gipshaltigem Inputmaterial. Es werden Untersuchungen zur Verbreiterung der Rohstoffbasis durch Einkopplung spezifischer mineralischer Stoffströme durchgeführt, die im Ergebnis zu einer Reduktion des Blähmittelbedarfs und einer Absenkung der Brenntemperatur führen sollen. Die Herstellung ausreichender Mengen Leichtgranulate für eine umfassende Charakterisierung nach Norm und die Praxiserprobung in bekannten Anwendungen und neuen Einsatzfeldern ist ein weiteres Projektziel. KW - Bau- und Abbruchabfälle KW - Bauschutt KW - Leichtgranulat KW - Leichte Gesteinskörnung KW - Gipsrückgewinnung PY - 2024 UR - https://www.ernst-und-sohn.de/mauerwerk-kalender-2024-schwerpunkte-klimagerechtes-und-nachhaltiges-bauen-befestigungen-bauen-im?tab=inhalt#rs SN - 978-3-433-03408-8 SP - 515 EP - 518 PB - Ernst & Sohn CY - Berlin AN - OPUS4-60356 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Müller, Thoralf T1 - Field exposure studies of austenitic and duplex stainless steels in tunnel atmospheres N2 - Due to the high corrosivity that are present in road tunnel structures, cleaning and maintenance work on stainless steel components in the tunnels is carried out at regular intervals in the tunnels, which means that parts of the lanes or the whole tunnel have to be temporarily closed. To reduce these traffic disruptions and maintenance costs, it is important to reduce the work that is needed for cleaning and maintenance of stainless steel components in road tunnels. One possibility is the identification and utilization of better suited alternatives to the commonly used austenitic stainless steels AISI 316L and AISI 316Ti. Thus, a field exposure study was carried out in different road tunnels throughout Germany to qualify different duplex and lean duplex stainless steels for tunnel constructions. The proposed scientific poster gives an overview of results after the first three years of exposure in three different road tunnels. Samples of different stainless steels were placed in different areas of the tunnel – at lane height and at the ceiling. Some samples were exposed under sheltered conditions. Pit depths were evaluated on the free surface and in crevice areas after each year of exposure. The investigations show that duplex stainless steels have a comparable or even better corrosion resistance than austenitic steels in tunnel atmospheres T2 - Stainless Steel World Conference & Expo 2023 CY - Maastricht, Netherlands DA - 26.09.2023 KW - Corrosion KW - Atmosphere KW - Tunnel KW - Stainless Steel PY - 2023 AN - OPUS4-58487 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Seher, Julia T1 - Lightweight aggregates made from construction and demolition waste - Application in lightweight concrete and mortars N2 - Heterogeneous construction and demolition waste can be used as raw material to produce lightweight aggregates (LWA) similar to expanded clays. In the joint research project “REALight”, LWA were produced from masonry rubble in a thermal expanding process using a pilot production plant with a rotary kiln. Our research focuses on the characterisation of the novel LWA and their use in different hydraulically bound applications. Infra-lightweight concrete (ILC) was produced with the novel LWA, which accounts for two thirds of total aggregate volume, and Celitement, which is a hydraulic binder with a low carbon footprint. Its dry bulk density is ≤ 800 kg/m³. Strength and durability properties are comparable to ILC data from the literature. Lime-based repair mortars (LRM) containing LWA are beneficial for sandstone conservation due to their similar properties regarding porosity, water absorption and strength. A two-layer repair mortar system, which consists of a filling mortar to fill large voids and a covering mortar to modulate the surface texture to the historic sandstone, was developed. In our contribution, we present results of the LWA characterisation according to the European standard EN 13055:2016. Requirements and challenges of the use of the novel LWA in ILC and LRM are discussed. T2 - V. International Conference Progress of Recycling in the Built Environment (V. PRE) CY - Weimar, Germany DA - 10.10.2023 KW - CDW recycling KW - Lightweight aggregates KW - Masonry rubble KW - Lightweight concrete KW - Repair mortar PY - 2023 AN - OPUS4-58540 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schraut, Katharina T1 - Production of a hydraulic material from post-treated steelmaking slags N2 - Steelmaking slag is a by-product of steel production of which 4.5 Mt were produced in 2020 in Germany alone. It is mainly used in road construction, earthwork and hydraulic engineering. A smaller part is returned to the metallurgical circle, used as fertilizer or landfilled. With this use, iron oxides still contained in steelmaking slag are lost. In addition, the possibility of producing higher-grade products from steelmaking slag is foregone. In recent decades, many researchers have investigated the production of Portland cement clinker and crude iron from basic oxygen furnace slags (BOFS) via a reductive treatment. Carbothermal treatment of liquid BOFS causes a reduction of iron oxides to metallic iron, which separates from the mineral phase due to its higher density. Simultaneously, the chemical composition of the reduced slag is adapted to that of the Portland cement clinker. In this study, German BOFS was reduced in a small-scale electric arc furnace using petrol coke as a reducing agent. The resulting low-iron mineral product had a similar chemical composition to Portland cement clinker and was rich in the tricalcium silicate solid solution alite (Ca3SiO5). Based on its chemical and mineralogical composition, similar to that of Portland cement clinker, the reduced BOFS has the potential to react comparably. In our study, the reduced BOFS produced less heat of hydration compared to OPC and its hydraulic reaction was delayed. However, adding gypsum has been shown to accelerate the hydration rate of the reduced BOFS compared to that known from the calcium silicates of Portland cement clinker. Further research to improve the hydraulic properties of the reduced slag is essential. If successful, producing a hydraulic binder and crude iron from BOFS could have economic and ecological benefits for both the cement and steel industry. T2 - 16th International Congress on the Chemistry of Cement ICCC 2023 CY - Bangkok, Thailand DA - 18.09.2023 KW - Steelmaking slag KW - Alite hydraulic reactivity KW - Clinker substitute PY - 2023 AN - OPUS4-58522 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Müller, Thoralf T1 - Bedingungen für den schadensfreien Einsatz von nichtrostenden Stählen N2 - Der Vortrag beleuchtet die Passivität von nichtrostenden Stählen und erläutert anhand von praktischen Schadensfällen den korrosionsschutzgerechten Einsatz dieser Werkstoffe T2 - VdEh Seminar "Nichtrostende Stähle - Eigenschaften und Anwendungen" CY - Düsseldorf, Germany DA - 06.06.2023 KW - Korrosion KW - Nichtrostende Stähle KW - Passivität KW - PREN PY - 2023 AN - OPUS4-57618 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schraut, Katharina T1 - Production of an alite-rich material from reduced basic oxygen furnace slags N2 - Basic oxygen furnace slag (BOFS) is a by-product of steelmaking of which about 10.4 Mt are produced annually in the EU. BOFS is mostly used in road construction, earthwork and hydraulic engineering. However, in this use, the iron bound in BOFS is lost and the opportunity to produce higher value products from BOFS is forgone. In recent decades, many researchers have investigated the production of both Portland cement clinker and crude iron from BOFS via a thermochemical reductive treatment. The reductive treatment of liquid BOFS causes a reduction of iron oxides to metallic iron, which separates from the mineral phase due to its higher density and can be recovered. An advantage of this process is that simultaneously the chemical composition of the reduced BOFS is adapted to that of Portland cement clinker and the hydraulic reactive mineral alite (Ca3SiO5) is formed. In this study, German BOFS was reduced in a small-scale electric arc furnace and a low-iron mineral product rich in alite was produced. Despite a chemical and mineralogical composition similar to that of Portland cement clinker, the reduced BOFS produced less heat of hydration, and its reaction was delayed compared to Portland cement. However, adding gypsum accelerated the hydration rate of the reduced BOFS. Further research to improve the hydraulic properties of the reduced BOFS is essential. If successful, the production of a hydraulic material and crude iron from BOFS could have economic and ecological benefits for both the cement and steel industry. T2 - GeoBerlin 2023 CY - Berlin, Germany DA - 04.09.2023 KW - BOFS KW - Alite KW - Hydraulic reactivity PY - 2023 AN - OPUS4-58206 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Müller, Thoralf T1 - Spannungsrisskorrosion an Bauteilen aus nichtrostenden Edelstählen - Bittere Erfahrungen in der Vergangenheit und sichere Verwendung in der Gegenwart N2 - Der Vortrag beschreibt die grundlegenden Voraussetzungen für das Auftreten von Spannungsrisskorrosion an nichtrostenden Stählen und erläutert den Schadensmechanismus bis zum Versagen des Werkstoffs. Abgeleitet von den notwendigen Voraussetzungen für das Auftreten von SpRK werden werkstoff, medien und belastungsabhängige Einflussfaktoren erläutert, die die Beständigkeit der Werkstoffe gegenüber dieser Schädigungsart positiv wie auch negativ verändern. Weiterhin werden historische und aktuelle Schadensfälle präsentiert und Ursachen, Folgen und mögliche Fehlervermeidung disktutiert. Abschließend werden Prüfverfahren zum Nachweis der Empfindlichkeit von nichtrostenden Stählen gegenüber SpRK näher beschrieben. T2 - fkss Infotag 01/2024 CY - Esslingen, Germany DA - 11.01.2024 KW - Korrosion KW - Spannungsrisskorrosion KW - Nichtrostender Stahl KW - Korrosionsprüfung KW - Schwimmhallen PY - 2024 AN - OPUS4-59355 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Seifert, Lando T1 - Nichtrostender Stahl im Kontakt mit anderen Werkstoffen N2 - Der Beitrag zeigt die Mechanismen, Voraussetzungen und Einflussgrößen der Bimetallkorrosion wichtiger Werkstoffe im Kontakt mit nichtrostenden Stahl anhand von verschiedenen Beispielen. Darüber hinaus wird das Korrosionsverhalten von nichtrostenden Stahl im Kontakt mit Holz als saurer Baustoff und mit Beton als alkalischer Baustoff beschrieben. T2 - VDEh Seminar Korrosionsverhalten nichtrostender Stähle CY - Düsseldorf, Germany DA - 30.01.2024 KW - Bimetallkorrosion KW - Nichtrostender Stahl KW - Saure und alkalische Baustoffe KW - Potentialbeeinflussung der Kontaktpartner PY - 2024 AN - OPUS4-59456 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Seher, Julia T1 - Anwendung der Leichtgranulate in Mörtel und Beton N2 - Im Verbundforschungsprojekt REALight wurden Leichtgranulate aus gemischtem Mauerwerkbruch in einem thermischen Blähverfahren im Pilotmaßstab hergestellt. Im Teilprojekt der BAM stand die Charakterisierung dieser Leichtgranulate und ihre Anwendung in gebundenen Systemen im Vordergrund. Im Rahmen des Abschlussvortrags wurden Ergebnisse zur Entwicklung von Steinergänzungsmörteln sowie Infraleichtbeton vorgestellt. T2 - Kolloquium "Nachhaltig effizient - Ressourcen des zukünftigen Bauens" CY - Berlin, Germany DA - 18.01.2024 KW - Leichtgranulat KW - Mauerwerkbruch KW - Steinergänzungsmörtel KW - Denkmalpflege KW - Infraleichtbeton KW - Leichtbeton PY - 2024 AN - OPUS4-59398 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Müller, Constanze A1 - Seher, Julia A1 - Martin, Falk A1 - Schnell, Alexander A1 - Rübner, Katrin T1 - Leichtgranulate aus gemischtem Mauerwerkbruch für die Anwendung in Infraleichtbeton T1 - Lightweight granular materials made from mixed masonry rubble for use in infra-lightweight concrete N2 - Infraleichtbeton zeichnet sich durch eine äußerst geringe Trockenrohdichte von maximal 800 kg/m³ aus, bei gleichzeitig ausreichender Festigkeit. Daraus resultieren geringe Wärme- und Schallleitfähigkeiten. Dies ermöglicht den Einsatz als Sichtbeton in Wandelementen ohne die Notwendigkeit einer zusätzlichen Dämmschicht. Vielversprechend erscheint der Einsatz von Leichtgranulaten in Infraleichtbeton, um seinen ökologischen Fußabdruck zu reduzieren und somit ein energieeffizientes und zugleich nachhaltiges Bauen zu ermöglichen. Die Leichtgranulate werden in einem thermo-chemischen Prozess aus gemischtem Mauerwerkbruch hergestellt. Ihre Verwendung bietet neben der Alternative zu herkömmlichen leichten Gesteinskörnungen auch die Möglichkeit, Abfallprodukte sinnvoll zu nutzen. In diesem Artikel werden die Leichtgranulate vorgestellt, ihre Anwendung in Infraleichtbeton geprüft und mit konventionellem Blähton verglichen. N2 - Infra-lightweight concrete exhibits an extremely low dry bulk density of up to 800 kg/m³ while also providing sufficient strength, resulting in low thermal and acoustic conductivity. This allows it to be used as exposed concrete in wall panels without requiring an additional insulating layer. Using lightweight granular materials in infra-lightweight concrete appears to be promising for reducing its environmental footprint and thus enabling energy-efficient and sustainable construction. Lightweight granules are produced from mixed masonry rubble in a thermo-chemical process. In addition to being an alternative to conventional lightweight aggregates, their use also provides the opportunity to put waste products to good use. This article reports on lightweight granules, their use in infra-lightweight concrete, and related tests in comparison to conventional expanded clay. KW - Infraleichtbeton KW - Leichtgranulat KW - Mauerwerkbruch KW - Recycling KW - Leichte Gesteinskörnungen PY - 2024 VL - 90 IS - 7 SP - 52 EP - 59 PB - Bauverlag CY - Gütersloh AN - OPUS4-60557 LA - mul AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Seifert, Lando A1 - Müller, Thoralf A1 - Ebell, Gino ED - Pillai, Radhakrishna G. T1 - Development of a new test method for assessing the susceptibility of prestressing steels to hydrogen-induced stress corrosion cracking N2 - For prestressing steel’s factory production control, approvals, and continuous surveillance in Germany, a susceptibility test against hydrogen-induced stress corrosion cracking is performed. The measured time to fracture results (in hours) must be reproducible and reliable in the test. ISO 15630-3 gives currently unpersuasive and diverging results using a free corrosion approach for hydrogen charging. A newly developed test method uses cathodic polarization for defined hydrogen charging instead of an uncontrolled and variable electron supply by metal dissolution during free corrosion. With this new test method, a reliable differentiation is possible between highly susceptible-known “old-type” quenched and tempered prestressing steel, i.e., Neptun, Hennigsdorfer, Sigma, and currently approved cold-drawn wires St 1470/1670 (CDS-1670) and St 1570/1770 (CDS-1770). The reproducibility of the new test method was evaluated in a round-robin test with eight attended testing institutes on a St 1470/1670 (CDS-1670) batch. T2 - Conference CONSEC24 CY - Chennai, India DA - 25.09.2024 KW - Hydrogen charging KW - ISO 15630-3 KW - Prestressing steels KW - Round-robin KW - Stress corrosion cracking PY - 2024 UR - https://consec24.com/# SP - 1 EP - 8 PB - Indian Institute of Technology (IIT) Madras, Centre of Excellence on Technologies for Low Carbon & Lean Construction CY - Chennai, India AN - OPUS4-61163 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Müller, Thoralf T1 - Bericht aus dem ISO-Gremium ISO TC 156 WG4 N2 - Der Vortrag gibt einen Überblick über die Tätigkeiten der Working Group 4 "Atmospheric Corrosion" des ISO Gremiums ISO TC 156 . Es werden neuste Informationen zum Stand verschiedener Normen aus dem Ausschuss wiedergegeben. T2 - GfKorr Gemeinschaftssitzung der AKs "Atmosphärische Korrosion" und "Korrosionsschutz in der Elektronik und Mikrosystemtechnik" CY - Online meeting DA - 05.12.2024 KW - Corrosion KW - Standards KW - Atmospheric Corrosion PY - 2024 AN - OPUS4-62305 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Seifert, Lando T1 - New Stress Corrosion Cracking Test Method for Prestressing Steel Wires N2 - This presentation at CONSEC24 gives an overview of the new stress corrosion cracking test for prestressing steel wires using cathodic polarisation. Design of Experiments (DOE) studies on prestressing levels and cathodic current density on time to fracture will be presented, testing different prestressing steels. Finally, an experimental solution for testing strands is proposed. T2 - 10th International Conference on CONcrete under SEvere Conditions – Environment and Loading 2024 (CONSEC24) CY - Chennai, India DA - 25.09.2024 KW - Prestressing Steels KW - ISO 15630-3 KW - Hydrogen-induced Stress Corrosion Cracking KW - Brittle Fracture KW - Hydrogen Charging PY - 2024 AN - OPUS4-61166 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Seifert, Lando T1 - Influence of Prestress Level on Susceptibility to HiSCC of Prestressed Steels N2 - The BAM developed a new test method for assessing susceptibility to hydrogen-induced stress corrosion cracking (HiSCC) of prestressed steel, especially for wires. The setup contains polished specimens pre-stressed to a constant 80% Rm stress level. The specimens are constantly charged with hydrogen during the test by an electrochemically applied cathodic current density. The time to brittle fracture is measured. The new test method can provide a sensitive separation between different kinds of susceptible prestressed steel wires by fracture times. This enables further parameter studies with load level and cathodic current density variation. Therefore, known as high-susceptible quenched and tempered prestressing wires of “old-type” (without alloying Cr and manufactured before 1965), Hennigsdorfer and Neptun and currently approved cold-drawn wires were tested. A design of experiments (DOE) statistical model of time to fracture was calculated for the three wires. A significant susceptibility change appears in specific load level ranges, this is the contribution of this EUROCORR lecture. T2 - Conference EUROCORR 2024 CY - Paris, France DA - 01.09.2024 KW - Prestressing Steels KW - ISO 15630-3 KW - Hydrogen-induced Stress Corrosion Cracking KW - Brittle Fracture KW - Hydrogen Charging PY - 2024 AN - OPUS4-60988 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ebell, Gino A1 - Müller, Thoralf A1 - Burkert, Andreas ED - G. Pillai, R. T1 - Stress Corrosion Cracking in Prestressed Concrete Bridge – A Case Study N2 - Bridge structures built using the prestressing block method can exhibit hydrogen-induced stress cracks across the entire cross-section of a prestressing channel due to their design. Crack growth can progress over the service life as a result of dynamic loading and lead to prestressing wire fractures. T2 - Consec 2024 CY - Chennai, India DA - 25.09.2024 KW - Corrosion KW - Spannungsrisskorrosion KW - Stress corrosion cracking KW - Hydrogen KW - Spannstahl PY - 2024 SP - 72 EP - 78 CY - Chennai AN - OPUS4-61330 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Burkert, Andreas A1 - Lehmann, Jens T1 - Einfluss der Oberflächennachbearbeitung auf die Korrosionsbeständigkeit von Schweißnähten N2 - Bedingung für den schadensfreien Einsatz nichtrostender Stähle ist die vollständige Ausbildung der Passivschicht. Voraussetzung dafür sind glatte, blanke, saubere Oberfläche, eine gleichmäßige Elementverteilung, wenig Ausscheidungen und Verunreinigungen. Eine mögliche Beeinflussung der Gefügeausbildung durch Warmumformung und durch die schweißtechnische Verarbeitung sind zu beachten. Anlauffarben müssen durch geeignete geeignete chemische bzw. mechanische Nachbehandlung entfernt werden. Eine ausreichende Nachbehandlung kann durch elektrochemische Prüfverfahren ebenso sichergestellt werden wie mittels der KorroPad-Prüfmethode. Letzte ist einfach und schnell in der Anwendung und ermöglicht es dem Verarbeiter, die Geeignetheit einer Nachbehandlung zu überprüfen. T2 - ISER Kursleiterfortbildung HWK Dresden CY - Dresden, Germany DA - 23.09.2024 KW - Korrosionsschutz KW - KorroPad KW - Nichtrostender Stahl KW - Prüfmethoden KW - Schweißnaht PY - 2024 AN - OPUS4-61382 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Burkert, Andreas T1 - Bedingungen für den schadensfreien Einsatz von nichtrostenden Stählen N2 - Unter Passivität versteht man den Korrosionsschutz durch dünne, festhaftende Schichten aus Korrosionsprodukten. Für den schadensfreien Einsatz nichtrostender Stähle ergeben sich daraus zwei grundsätzliche Anforderungen. Erstens muss sich die Passivschicht vollständig ausbilden können. Dabei sind die Oberflächenausführung, die mechanische Bearbeitung, die Elementverteilung, Ausscheidungen, die Wärmeeinbringung z.B. bei der schweißtechnischen Verarbeitung, Anlauffarben, sowie die chemische Nachbehandlung bzw. Konditionierung der Oberflächen von großer Bedeutung. Zweitens muss die Repassivierung von Defektstellen unter den Einsatzbedingungen möglich sein. Für das Repassivierungsvermögen sind die Legierungszusammensetzung, mögliche kritische Betriebszustände, prozessbedingte Besonderheiten, wie etwa Stagnationsbedingungen und Reinigungsprozesse von Bedeutung. T2 - Nichtrostende Stähle - Eigenschaften und Anwendungen CY - Dusseldorf, Germany DA - 11.06.2024 KW - Korrosion KW - Passivität KW - Dauerhaftigkeit KW - Schadensursachen PY - 2024 AN - OPUS4-60298 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wiehle, Philipp A1 - Härder, Michelle A1 - Strangfeld, Christoph T1 - Quantification of moisture content in earth block masonry under natural climatic conditions N2 - The aim of this study is to accurately predict the moisture content in earth block masonry exposed to natural climatic conditions, which is a key factor in assessing its load-bearing capacity. Nuclear magnetic resonance relaxometry and humidity sensor measurements were carried out to quantify the moisture content. In addition, a customised test setup was developed to determine the capillary water absorption of earth blocks. This approach takes into account the deceleration of water absorption due to the swelling of clay minerals and organic additives, which leads to realistic transport coefficients in the hygroscopic range. This allows the moisture content of earth block masonry to be predicted accurately. With regard to the moisture behaviour of typical exterior wall constructions in living spaces, it was found that the equilibrium moisture content in earth block masonry is always lower than 65 % relative humidity, which corresponds to the permissible limit of the recently published German design standard for load-bearing earth block masonry. KW - Earth block masonry KW - NMR relaxometry KW - Hygrothermal simulation KW - Load-bearing capacity KW - Moisture content KW - Embedded humidity sensors PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-623518 DO - https://doi.org/10.1016/j.conbuildmat.2024.139513 VL - 459 SP - 1 EP - 10 PB - Elsevier Ltd. AN - OPUS4-62351 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz T1 - Characteristic Frequencies of Train-Induced Bridge, Track, Ground and Building Vibrations – Excitation and Mitigation N2 - The characteristic frequencies of train-induced vibrations are discussed in theory and experiment following the propagation of vibrations from the source to the receiver: 1. Out-of-roundness frequencies of the wheels, 2. sleeper-passage frequency, 3. the vehicle-track eigenfrequency, 4. band frequency of the impulses of the passing static axle loads, 5. car-length frequency and multiples, 6. axle-distance frequencies with two characteristic zeros, 7. bridge eigenfrequencies, 8. the cut-on frequency due to the layering, and 9. the cut-off frequency due to the material damping of the soil, 10. the building-soil eigenfrequency, 11. as a rigid building or flexible wall/column mode, 12. floor eigenfrequencies, 13. acoustic room resonances, 14. the „resonance“ frequency or cut-off frequency of a base isolation. Coincidences of some of these characteristic frequencies or frequency ranges can be typically problematic and mitigation measures at the track or at the building can be necessary. The bridge response to the passing static loads is deter¬mined by the axle-sequence spectrum, the eigenfrequency (transfer function) of the bridge, and the modal force or mode shape spectrum. The ground vibration has typically high frequencies for a stiff soil and low frequencies for a soft soil. The high amplitudes between the zeros of the axle-sequence spectrum are often measured in the ground vibrations, and they can be mitigated by soft support elements or a higher bending stiffness of the track. T2 - EVACES 2025 CY - Porto, Portugal DA - 02.07.2025 KW - Train-induced vibration KW - Axle-sequence spectrum KW - Vehicle-track eigenfrequency KW - Axle impulses PY - 2025 AN - OPUS4-63654 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Durlo Tambara Júnior, Luis Urbano T1 - Early hydration reactions of calcium sulfoaluminate cement in water and alkaline media N2 - This study investigates the early hydration of calcium sulfoaluminate (CSA) cement in water (CSAH) and 2M NaOH (CSA2M), both with a liquid/solid ratio of 0.5. Hydration kinetics were assessed using in situ X-ray diffraction, isothermal conduction calorimetry, ultrasonic pulse velocity (UPV) and mechanical strength measurements. The results indicate that in the CSA2M system, the maximum heat release occurs earlier, and UPV measurements reveal a more rapid increase in mechanical stiffness (Figure 1a). The presence of alkalis accelerates the dissolution of ye’elimite and anhydrite, leading to a shorter induction period and faster precipitation of ettringite (Figure 1b-d). The phase refinement confirmed a higher dissolution rate of anhydrite in the alkaline environment, while the formation of ettringite stabilizes within 10 hours. Initial dissolution (0–40 min) increases ion concentration, followed by accelerated ettringite formation (0.6–2.5 h) with rising heat flow and UPV. A secondary acceleration (2.5–4.3 h) occurs only in CSAH. Deceleration (2.5–10 h) leads to further stabilization, with reactions proceeding at a slower rate. At 25 h, CSAH reached 58.3% ettringite and CSA2M 48.2%. These findings contribute to a deeper understanding of the early hydration mechanisms of CSA cement and the impact of alkalis on phase evolution. T2 - 3rd International Workshop on Calcium Sulfoaluminate Cements CY - Leeds, UK DA - 23.06.2025 KW - Calcium sulfoaluminate cement KW - Ultrasonic pulse velocity KW - Early hydration KW - Alkali KW - In situ XRD PY - 2025 AN - OPUS4-63758 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Burkert, Andreas T1 - Qualitätsüberwachung durch das KorroPad®-Verfahren N2 - Am Beispiel des KorroPad®-Verfahrens wird ein Ergebnis des H2Mare Teilprojektes "TransferWind" vorgestellt. Im Rahmen des Vorhabens konnte für das Verfahren die DIN 50024:2025-07 erstellt und verabschiedet werden. Das Prüfverfahren ermöglicht es, die Barrierefunktion der Passivschicht auf nichtrostenden Stählen einfach und schnell, direkt durch die Verarbeiter zu prüfen und somit die werkstoffgerechte Verarbeitung sicherzustellen. Das Verfahren liefert ein optisches Prüfergebnis, ist zerstörungsfrei und ermöglicht eine direkte Intervention durch den Verarbeiter bei einer unvollständigen Ausbildung der Passivschicht. Damit kann es helfen spätere Korrosionserscheinungen an Bauteilen und Komponenten aus nichtrostenden Stählen zu vermeiden. Erforderliche Nacharbeiten wären insbesondere bei Offshore -Prozessanlagen mit erheblichen Kosten verbunden. T2 - Verbundtreffen PtX-Wind / Transferwind CY - Bremerhaven, Germany DA - 09.07.2025 KW - Nichtrostender Stahl KW - Passivität KW - KorroPad KW - Normung PY - 2025 AN - OPUS4-63745 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Eggert, Lara T1 - Korrosivitätsbestimmungen an Offshoreanlagen N2 - Im Rahmen des Teilprojektes PtX-Wind wurden verschiedene küstennahe sowie offshore Standorte beprobt, um die tatsächliche Korrosivität der Atmosphären zu bestimmen. Mit Offshore Auslagerungsversuchen auf einer Technikplattform (freibewitterter und überdachter Bereich) und an Windenergieanlagen (Außen- und Innenbereich), sollten Daten zur Korrosivität ermittelt werden. Diese stellen eine Grundlage für die dauerhafte und gleichzeitige wirtschaftliche Auslegung des Korrosionsschutzes für Offshore-Prozessanlagen dar. Für Offshore-Windkraftanlagen wird auf Grundlage der abgeschätzten Atmosphäre nach DIN ISO 9223 immer einer Korrosivitätskategorie C5/CX angenommen, was einen entsprechenden Aufwand für den Korrosionsschutz nach sich zieht. Bei den vorliegenden Untersuchungen zeigte sich, dass für Stahl ab einer Höhe von ca. 40 m über der Meeresoberfläche nur eine Korrosivitätskategorie von C3 bis C4 ermittelt wurde. Dies ist vergleichbar mit Standorten an küstennahen Bereichen bzw. Inseln, bei denen die Kategorie C3 vorliegt. Im teilklimatisierten Inneren des Turmes liegt die Korrosivitätskategorie nur bei C2. Die Korrosivitätskategorie C2 wurde aber auch für das nicht klimatisierte Air Transition Deck festgestellt. Auf Grundlage dieser Informationen kann die Auslegung des Korrosionsschutzes sowohl für Außenkomponenten als auch für Anlagenkomponenten in klimatisierten Containern abgeleitet werden. Für alle anderen küstennahen Standorten lag die ermittelte Korrosivität für Zink und Aluminium maximal bei C3. Für Kupfer wurden die höchsten Korrosionsraten mit C4 bis C5 ermittelt, was etwa bei der Auslegung des Korrosionsschutzes elektronischer Bauteile im Außenbereich entsprechend Beachtung finden muss. Neben den Korrosivitätsinformationen liefern die Auslagerungsversuche auch Informationen über die Performance typischer Konstruktionsmaterialien im Offshore Bereich, wie etwa nichtrostender Stähle sowie ausgewählter Korrosionsschutzmaßnahmen. Der Beitrag stellt ausgewählte Ergebnisse der Auslagerungskampagnen vor. T2 - H2Mare-Verbundprojekttreffen PtX-Wind & TransferWind CY - Bremerhaven, Germany DA - 09.07.2025 KW - Atmosphärische Korrosion KW - Standardproben KW - Offshore PY - 2025 AN - OPUS4-63767 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Eggert, Lara T1 - Möglichkeiten im Meerwasserlabor N2 - Das Meerwasserlabor am Eidersperrwerk wurde vorgestellt. Dabei lag der Fokus auf die elektrochemischen Versuchsmöglichkeiten, Monitoring von Versuchsparametern, atmosphärische Korrosion und der Bewuchs an getauchten Prüfkörpern. T2 - H2Mare-Verbundprojekttreffen PtX-Wind & TransferWind CY - Bremerhaven, Germany DA - 09.07.2025 KW - Meerwasserlabor KW - Maritime Korrosion PY - 2025 AN - OPUS4-63766 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Müller, Thoralf T1 - Field exposure studies of austenitic and duplex stainless steels in tunnel atmospheres N2 - Due to the high corrosivity that are present in road tunnel structures, cleaning and maintenance work on stainless steel components in the tunnels is carried out at regular intervals in the tunnels, which means that parts of the lanes or the whole tunnel have to be temporarily closed. To reduce these traffic disruptions and maintenance costs, it is important to reduce the work that is needed for cleaning and maintenance of stainless steel components in road tunnels. One possibility is the identification and utilization of better suited alternatives to the commonly used austenitic stainless steels AISI 316L and AISI 316Ti. Thus, a field exposure study was carried out in different road tunnels throughout Germany to qualify different duplex and lean duplex stainless steels for tunnel constructions. The proposed scientific poster gives an overview of results after the first three years of exposure in three different road tunnels. Samples of different stainless steels were placed in different areas of the tunnel – at lane height and at the ceiling. Some samples were exposed under sheltered conditions. Pit depths were evaluated on the free surface and in crevice areas after each year of exposure. The investigations show that duplex stainless steels have a comparable or even better corrosion resistance than austenitic steels in tunnel atmospheres. T2 - EUROCORR 2022 CY - Berlin, Germany DA - 28.08.2022 KW - Corrosion KW - Atmosphere KW - Tunnel KW - Stainless Steel PY - 2022 AN - OPUS4-55595 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Lorenzoni, Renata A1 - Fritsch, Tobias A1 - Kruschwitz, Sabine A1 - Bruno, Giovanni A1 - Schmidt, Wolfram T1 - Mechanical analysis of cement-biochar composites using in-situ X-ray microtomography and digital volume correlation N2 - This study addresses biochar as a potential carbon-sequestering filler in cement and examines its effect on mechanical properties using X-ray computed tomography (XCT) and digital volume correlation (DVC). DVC was reliably used to measure global displacement and has proven to be an effective method for correcting displacement data obtained from mechanical tests conducted without traditional instrumentation, such as extensometer. This made it possible to measure strain and Young’s modulus accurately. The results demonstrate that while 5 vol% biochar replacement had minimal effect on mechanical properties, a 25 vol% biochar replacement caused a 35 % reduction in Young’s modulus and 40 % reduction in the ultimate compressive strength. Additionally, DVC detected strain concentrations and predicted material failure locations even when cracks could not be quantified using XCT alone. Moreover, the study reveals that biochar particles, due to their sharp geometry, increase internal shear strain during uniaxial compression, unlike round phases such as pores. KW - Cementitious materials KW - Biochar KW - Mechanical proprieties KW - In-situ X-ray microtomography KW - Digital volume correlation PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-638065 DO - https://doi.org/10.1016/j.conbuildmat.2025.142511 SN - 1879-0526 VL - 490 PB - Elsevier Ltd. AN - OPUS4-63806 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Lorenzoni, Renata T1 - Effects of polysaccharide rheology modifying admixtures on early hydration of Portland cement and LC3 N2 - The construction sector accounts for 40% of global carbon emissions, and its impact is set to rise as growing populations drive increased construction activity, particularly in the Global South. In Africa, where cement is expensive and urban growth is rapid, innovative, locally tailored solutions are urgently needed. To address this environmental challenge, a common approach is to use limestone-calcined clay cement (LC3), which allows for approximately 50% clinker reduction with equivalent performance to OPC. However, LC3 often presents challenges in terms of fresh concrete properties due to its influence on rheological properties. This paper proposes the use of gum Arabic (GA), a polysaccharide biomass abundant in Africa, as a rheology modifying admixture. These local admixtures would provide access to chemical admixtures for a wider range of concrete users, including the informal sector, and create local value chains while minimising dependence on global supply streams. Rheometer, 1H nuclear magnetic resonance (1H NMR) and heat flow calorimetry (HFC) techniques were used to understand the influence of GA on both OPC and LC3 systems by monitoring their early hydration. Rheological results reveal that GA affects the fresh paste rheology of OPC and LC3 systems differently, requiring different dosages to achieve optimal performance. Heat flow and NMR analyses further confirm that GA retards the hydration reactions in both systems. T2 - Sustainable Construction in Africa 2025 CY - Nairobi, Kenya DA - 20.05.2025 KW - Polysaccharide-based admixture KW - Early hydration KW - LC3 KW - OPC PY - 2025 AN - OPUS4-63814 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Auersch, Lutz T1 - Mitigation of railway-induced ground vibration by soft support elements and a higher bending stiffness of the track N2 - The mitigation of train-induced ground vibrations by track solutions is investigated by calculations and measurements. The calculation by a wavenumber domain method includes the correct vehicle–track interaction and the correct track–soil interaction. Some theoretical results for elastic elements and an increased bending stiffness of the track are presented where the force transfer of the track and the vehicle–track interaction are calculated for the high-frequency dynamic mitigation, and the force distribution along the track is calculated for the low-frequency mitigation which is due to the smoother impulses from the passing static loads. Measurement results for the ground vibration near isolated and un-isolated tracks are given for several under-sleeper pads, for under-ballast mats, and for several under-ballast plates and ballast troughs. The elastic elements yield a resonance frequency of the vehicle–track–soil system and a high-frequency reduction of the dynamic axle loads which depends mainly on the softness of the pads or mats and which can be improved by a higher sleeper mass. In addition, all troughs and most of the soft elements show a low-frequency reduction which is attributed to the scattered impulses of the static axle loads. Besides this main contribution of the article, the problem of a soft reference section on a different soil is discussed and recommendations for better ground vibration measurements of mitigation effects are given. KW - Railway track KW - Elastic elements KW - Bending stiffness KW - Ground vibration KW - Mitigation KW - Lowfrequency reduction KW - Axle impulses PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-612568 DO - https://doi.org/10.3390/app14031244 VL - 14 IS - 3 SP - 1 EP - 14 PB - MDPI CY - Basel AN - OPUS4-61256 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Auersch, Lutz T1 - Some resonance effects of non-typical trains and railway bridges investigated by a frequency-domain method N2 - The resonances of railway bridges have often been analysed for short bridges under periodical high-speed trains, for simply supported one-span bridges, for the fundamental bridge mode, and by time-domain analyses. Many time-consuming calculations have been performed to establish simplified rules for standards. In this contribution, the passage of different (existing, new and hypothetic) trains over different (simply supported, integral, multi-span, continuous) bridges will be analysed in frequency domain by using three separated spectra with the purpose to get a better physical insight in the phenomena. At first, the excitation spectrum of the modal forces is built by the mode shape and the passage time of the train over the bridge. The second spectrum is the frequency response function of the bridge which include the modal frequency, damping and mass. The third part is the spectrum of the axle sequence of an arbitrary train which is not limited to periodical or specific (conventional, articulated, regular or standard) trains and which does not include any bridge parameters. The final solution in frequency domain is obtained as the product of these three complex, strongly varying spectra for the dominating bridge mode or in general as the sum of these products over all relevant bridge modes. The time domain solution is obtained via the inverse Fourier transform, and the resulting time histories have been successfully compared with some measurement results. The method is applied to the vertical and torsional modes of a mid-long single-span bridge on elastomeric bearings under standard train speeds, to a short two-span bridge under high-speed traffic, and to a long three-span integral bridge under long periodical freight trains. Different resonance and cancellation effects have been found for systematically varied train speeds according to the axle sequence of the whole train which is dominated by the two locomotives in that case. To be more specific, the first torsional mode of the mid-span bridge is excited for a train speed of 100 km/h whereas the second bending mode is excited for a train speed of 160 km/h. In both cases, the other mode is suppressed by the minima of the axle-distance spectra. In addition, the case of the German high-speed train ICE4, a Maglev train on a viaduct, and the very high-speed hyperloop case will be discussed briefly. In general, it is shown that resonance effects are also worth to be studied for freight and passenger trains with lower speeds. KW - Rail bridge KW - Resonance KW - ICE4 KW - MAGLEV KW - Hyperloop KW - Continuous bridge KW - Multi-span bridge PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-612595 DO - https://doi.org/10.1088/1742-6596/2647/25/252014 VL - 2647 SP - 1 EP - 11 PB - IOP Publishing AN - OPUS4-61259 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz T1 - Railway vibration – fast physics-based models for the prediction of ground vibration and the identification of track damage N2 - The following applications of machine learning will be discussed: 1. The prediction of the wave propagation from a railway line (completely physics based for surface lines, physics-based machine learning for tunnel lines) 2. The track behaviour for the emission of train-induced ground vibration (physics based for homogeneous soil, machine learning for layered soil) 3. Track damage detection and quantification from frequency response functions and moving load responses 4. Bridge damage detection and localisation from modal analysis and moving load 5. The use of axle-box acceleration for the identification of track/sub-soil condition and bridge resonances. The prediction of railway vibration usually needs time-consuming finite element, boundary element and wavenumber domain calculations. For a user-friendly prediction software however, fast calculations are needed. Several time-consuming detailed calculations have been used to develop simpler and fast models for the surface railway lines. The more challenging prediction from tunnel lines will be attacked by purely mathematical and by physics-informed machine learning. The dynamic stiffnesses of isolated or un-isolated railway tracks from detailed calculations with a continuous soil have been approximated with the simpler Winkler soil. The vehicle-track resonance (P2 resonance) rules the effect of the mitigation measures, and it can also be used for the on-board monitoring of the track and sub-soil condition. For the identification of track damage such as gaps between sleepers, track slabs and layers, detailed models with a continuous soil have been updated to get the best fit to the measured frequency response functions from hammer tests and the deformation pattern from the moving load response. Whereas the track damage can be locally identified, this is more difficult for bridges where the modal analysis gives mainly global information. The influence lines of the inclination for statically passing vehicles (locomotive, truck, compaction roller) have been used to localise bridge damage (stiffness variations). The on-board monitoring of rail bridges needs special conditions (regular trains with special speeds) to excite and measure the bridge resonance. T2 - 11th European Workshop on Structural Health Monitoring (EWSHM 2024) CY - Potsdam, Germany DA - 10.06.2024 KW - Vibration prediction KW - Track damage detection KW - Human and machine learning KW - Wave propagation KW - Surface line KW - Tunnel KW - Bridge resonance PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-612462 DO - https://doi.org/10.58286/29865 SN - 1435-4934 SP - 1 EP - 9 PB - NDT.net CY - Kirchwald AN - OPUS4-61246 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hering, Marcus A1 - Agasty, Amit A1 - Costard, René A1 - Hüsken, Götz A1 - Chruscicki, Sebastian A1 - Hicke, Konstantin T1 - Explosion effects on reinforced concrete structures – A preliminary study of scaling laws N2 - Blast tests are required to investigate accidental or intentional blast events and to assess the level of protection for people and facilities in critical infrastructures. Conducting large-scale field tests for complex scenarios is very resource intensive. Reliable small-scale experiments are a promising alternative. However, the scaling laws for the design of reinforced concrete structures under blast loads are not sufficiently established. In our research work, a consortium made up of three BAM departments, focuses on reinforced concrete structures that are suitable for the standardization of scaled blast tests. As part of the feasibility study, blast tests were carried out on test specimens of different sizes on the BAM Test Site for Technical Safety (TTS). Various reinforced concrete plates were tested and subjected to different blast loads. The blast tests included various measurement techniques to quantify the blast load and the behavior of the reinforced concrete plate. The blast load was measured with flush-mounted piezoelectric pressure gauges, while accelerometers and embedded fiber optic sensor cables were used to characterize the dynamic behavior of the plate under blast loading. In addition, damage characteristics were also determined using distributed fiber optic sensing. The application of these measurement techniques as well as the use of different numerical software tools offer the possibility to verify or adapt the scaling laws. T2 - 19th International Symposium on Interaction of the Effects of Munitions with Structures (19th ISIEMS) CY - Bonn, Germany DA - 09.12.2024 KW - Scaling KW - Blast KW - Fiber optic sensing PY - 2024 SP - 1 EP - 9 AN - OPUS4-62258 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Agasty, Amit T1 - Replica scaling of RC slabs under blast loading: a preliminary assessment N2 - Blast testing is undoubtedly the most straightforward and direct method of evaluating the blast resistance of a structure. For the calibration and validation of numerical models as well, blast tests must be carried out. However, true-scale prototype testing under different blast loading scenarios is not always feasible. Reliable small-scale experiments are a promising alternative. Application of dimensional analysis and similarity principals can be found in different engineering fields. For applications to the phenomenon of shock wave propagation, Hopkinson-Cranz or cube-root scaling is a well-established concept. When it comes to the scaling the structural response, research has predominantly focused on structures made of metallic materials. Scaled investigations with concrete or reinforced concrete (RC) structures remain limited, specifically under blast loading. In a preliminary study, we tested RC slabs at two different scales under near-field blast loading. Replica scaling, which is geometrical scaling while using the same materials at different scales, was implemented in the construction of the test specimens. The assessment of scaling and the discrepancy in its application was investigated by characterizing the blast loads, dynamic response, and damage. The experiments were supplemented by numerical simulations of these scenarios. The quantification of scenario-and-response-specific discrepancy can be used to modify the scaling laws, so that a blast assessment can be performed based on resource efficient small-scale tests. T2 - 25th International Physical Security Forum CY - Schwarzenburg, Switzerland DA - 11.05.2025 KW - Blast KW - RC slabs KW - Scaling PY - 2025 AN - OPUS4-63184 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Agasty, Amit A1 - Hering, Marcus T1 - Experimental and Numerical Analysis of Reinforced Concrete Structures Under Blast Loading: Scopes and Challenges N2 - Protection against terrorist or accidental scenarios in industrial settings requires suitable designs of structures to resist blast loads. Field testing as well as finite element simulations are among the techniques available to engineers in the understanding of the structural behavior against blast loading. As blast testing of complex scenarios can be very resource intensive, tests are generally performed for simplified scenarios. Numerical tools can be used to model these scenarios in order to get a better insight into blast loading, structural response and the resulting damage to the structure. In the next steps, the simplified scenario is successively modified in numerical simulations to incorporate complexities that cannot be covered in blast testing experiments. One of the conditions for this approach to work is that the original simplified numerical simulation is valid. The scopes and challenges encountered in such a validation are the focus of this presentation. A relatively ‘simple’ field test of a horizontal reinforced concrete (RC) slab subjected to blast loading is taken as an example for validation of the performance of numerical tools. The blast test incorporated various measurement techniques to quantify the blast load as well as the behavior of the RC slab. Blast load was measured using flush-mounted piezoelectric pressure gauges, whereas acceleration sensors and fiber-optic sensor cables were used to characterize the dynamic behavior of the slab under blast loading. Additionally, damage characteristics were ascertained also using fiber-optic sensing. The application of such measurement techniques, along with different numerical software available for the analysis of the scenario in question, demonstrate the scope of our contribution. T2 - 24th International Physical Security Forum Brussels CY - Brussels, Belgium DA - 15.04.2024 KW - Blast KW - Reinforced Concrete Structures KW - Numerical simulations PY - 2024 AN - OPUS4-60880 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hering, Marcus T1 - Explosion effects on reinforced concrete structures: A preliminary study of scaling laws N2 - Blast tests are required to investigate accidental or intentional blast events and to assess the level of protection for people and facilities in critical infrastructures. Conducting large-scale field tests for complex scenarios is very resource intensive. Reliable small-scale experiments are a promising alternative. However, the scaling laws for the design of reinforced concrete structures under blast loads are not sufficiently established. In our research work, a consortium made up of three BAM departments, focuses on reinforced concrete structures that are suitable for the standardization of scaled blast tests. As part of the feasibility study, blast tests were carried out on test specimens of different sizes on the BAM Test Site for Technical Safety (TTS). Various reinforced concrete plates were tested and subjected to different blast loads. The blast tests included various measurement techniques to quantify the blast load and the behavior of the reinforced concrete plate. The blast load was measured with flush-mounted piezoelectric pressure gauges, while accelerometers and embedded fiber optic sensor cables were used to characterize the dynamic behavior of the plate under blast loading. In addition, damage characteristics were also determined using distributed fiber optic sensing. The application of these measurement techniques as well as the use of different numerical software tools offer the possibility to verify or adapt the scaling laws. T2 - 19th International Symposium on Interaction of the Effects of Munitions with Structures (19th ISIEMS) CY - Bonn, Germany DA - 09.12.2024 KW - Blast KW - Fiber optic sensing KW - Scaling PY - 2024 AN - OPUS4-62260 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Costard, René T1 - Auswirkungsbetrachtungen auf Strukturen T1 - Scaling of Blast Effects on Reinforced Concrete Structures N2 - Protection against terroristic or accidental scenarios in industrial settings requires suitable designs of structures to resist blast loads. Field testing as well as finite element simulations are among the techniques available to engineers in the understanding of the structural behavior against blast loading. As blast testing of complex scenarios can be very resource intensive, tests are generally performed for simplified scenarios. Numerical tools can be used to model these scenarios to get better insight into blast loading, structural response, and the resulting damage to the structure. During the next steps, the simplified scenario is successively modified in numerical simulations to incorporate complexities that cannot be covered in blast testing experiments. One of the conditions for this approach to work is that the original simplified numerical simulation is valid. The scopes and challenges encountered in such a validation are the focus of this presentation/article. A relatively ‘simple’ field test of a horizontal reinforced concrete (RC) slab subjected to blast loading is taken as an example for validation of the performance of numerical tools. The blast test incorporated various measurement techniques to quantify the blast load as well as the behavior of the RC slab. Blast load was measured using flush mounted piezoelectric pressure gauges, whereas acceleration sensors and fiber-optic sensor cables were used to characterize the dynamic behavior of the slab under blast loading. Additionally, damage characteristics were ascertained also using fiber optic sensing. The application of such measurement techniques, along with different numerical software available for the analysis of the scenario in question, demonstrate the scope of our contribution. When it comes to the challenges, it begins with proper instrumentation of the test specimen followed by the data processing. For numerical modelling, geometric conditions with appropriate boundary constraints, physical conditions such as the configuration of the rebars, as well as material parameters add to this challenge. The issues of choosing appropriate material models and comparison of results with multiple software tools will be discussed. This discussion forms the basis for a coherent approach to technical-safety assessment of blast effects on structures in its broader sense. T2 - Beiratssitzung Infrastruktur CY - Berlin, Germany DA - 11.04.2024 KW - Blast KW - Scaling KW - Fiber optic sensing KW - CFD KW - FEM PY - 2024 AN - OPUS4-59849 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Costard, René T1 - Explosionsauswirkungen auf Strukturen Versuche und Simulationen N2 - Vorstellung der Versuche von Explosionsversuchen auf dem TTS. Diese werden ergänzt durch die Ergebnisse durchgeführter Simulationen und zeigen die Wirkung von zivilen Explosivstoffen auf Gebäudestrukturen und die aufgetretenen Schädigungen. T2 - 46. Informationstagung Sprengtechnik CY - Siegen, Germany DA - 25.04.2025 KW - Explosivstoff KW - Skalierung KW - Strukturauswirkung KW - Numerische Simulation PY - 2025 AN - OPUS4-62998 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Maack, Jürgen A1 - Eidenmüller, Moritz A1 - Auersch, Lutz T1 - Prognose von Erschütterungs- und Sekundärschall- Immissionen an Bahnlinien unter Verwendung von FEM Gebäudemodellen N2 - Die Errichtung von Wohngebäuden an Bahnstrecken erfordert Betrachtungen zur Begrenzung der Erschütterungs- und Sekundärschallimmissionen. Hierzu werden spektrale Prognoseverfahren ausgehend von Freifeldmessungen eingesetzt. Im rechnerischen Modell werden die Teilaspekte der Körperschallübertragung mit Hilfe von spektralen Übertragungsfunktionen beschrieben. Kenntnis über die Zusammenhänge dieser spektralen Übertragungsfunktionen erhält man im Wechselspiel von: - Messergebnissen von Körperschall- und Luftschallmessungen für einzelne Übertragungssysteme - Modellberechnungen mit der Finite-Elemente-Methode, Parameterstudien, Abgleich mit Messergebnissen - Modellberechnung mit der Finite-Elemente-Methode zur Wechselwirkung des schwimmenden Estrichs mit dem Gebäude T2 - VDI-Tagung Baudynamik CY - Würzburg, Germany DA - 02.04.2025 KW - Bahnerschütterungen KW - Gebäudemodelle KW - Schwimmender Estrich KW - Sekundärschall PY - 2025 SN - 978-3-18-092447-2 SN - 0083-5560 VL - 2447 SP - 301 EP - 314 PB - VDI-Verlag CY - Düsseldorf AN - OPUS4-62887 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz T1 - Erschütterungsprognose mit KI? Schnelle Ersatzmodelle und physikbasiertes maschinelles Lernen in der Bauwerk-Boden-Dynamik N2 - Erschütterungsprognosen können mit sehr detaillierten Modellen durchgeführt werden. Dies ist sowohl bei der Erstellung des Modells (zum Beispiel für ein Finite-Element-Modell für Boden und Bauwerk), als auch bei der Berechnung zeitaufwändig, von einigen Minuten für die Wellenausbreitung in geschichteten Böden mit Wellenzahlintegralen bis zu mehreren Stunden für Randelementlösungen für die korrekte Bauwerk-Boden-Wechselwirkung. Hier sind einfache und schnelle Ersatzmodelle von Vorteil, die die Ergebnisse der detaillierten Berechnungen gut wiedergeben. Diese Ersatzmodelle können vollständig auf physikalischen Überlegungen beruhen (white-box Modelle) oder mit Hilfe von maschinellem Lernen aus einer Vielzahl von detaillierten Rechenergebnissen erzeugt werden (black-box Modelle). Erfahrungen mit black-box Modellen zeigen, dass es sinnvoll ist das maschinelle Lernen mit physikalischen Informationen anzureichern (grey-box Modelle). Es werden Anwendungsmöglichkeiten für physikbasiertes maschinelles Lernen im Bereich von Bahnerschütterungen aufgezeigt, die Erschütterungsemission durch die Fahrzeug-Fahrweg-Wechselwirkung, die Wellenausbreitung im Boden, die Erschütterungsimmission in Gebäude, Gleisschäden und das Monitoring von Eisenbahnbrücken. T2 - VDI-Tagung Baudynamik CY - Würzburg, Germany DA - 02.04.2025 KW - Bahnerschütterungen KW - Emissionsmodell KW - Immissionsmodell KW - Transmissionsmodell KW - Tunnelausbreitung KW - Gleisüberwachung PY - 2025 SN - 978-3-18-092447-2 SN - 0083-5560 VL - 2447 SP - 53 EP - 64 PB - VDI-Verlag CY - Düsseldorf AN - OPUS4-62886 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz T1 - Erschütterungsprognose mit KI? Schnelle Ersatzmodelle und physikbasiertes maschinelles Lernen in der Bauwerk-Boden-Dynamik N2 - Erschütterungsprognosen können mit sehr detaillierten Modellen durchgeführt werden. Dies ist sowohl bei der Erstellung des Modells (zum Beispiel für ein Finite-Element-Modell für Boden und Bauwerk), als auch bei der Berechnung zeitaufwändig, von einigen Minuten für die Wellenausbreitung in geschichteten Böden mit Wellenzahlintegralen bis zu mehreren Stunden für Randelementlösungen für die korrekte Bauwerk-Boden-Wechselwirkung. Hier sind einfache und schnelle Ersatzmodelle von Vorteil, die die Ergebnisse der detaillierten Berechnungen gut wiedergeben. Diese Ersatzmodelle können vollständig auf physikalischen Überlegungen beruhen (white-box Modelle) oder mit Hilfe von maschinellem Lernen aus einer Vielzahl von detaillierten Rechenergebnissen erzeugt werden (black-box Modelle). Erfahrungen mit black-box Modellen zeigen, dass es sinnvoll ist das maschinelle Lernen mit physikalischen Informationen anzureichern (grey-box Modelle). Es werden Anwendungsmöglichkeiten für physikbasiertes maschinelles Lernen im Bereich von Bahnerschütterungen aufgezeigt, die Erschütterungsemission durch die Fahrzeug-Fahrweg-Wechselwirkung, die Wellenausbreitung im Boden, die Erschütterungsimmission in Gebäude, Gleisschäden und das Monitoring von Eisenbahnbrücken. T2 - VDI-Tagung Baudynamik CY - Würzburg, Germany DA - 02.04.2025 KW - Bahnerschütterungen KW - Emissionsmodell KW - Immissionsmodell KW - Transmissionsmodell KW - Tunnelausbreitung KW - Gleisüberwachung PY - 2025 AN - OPUS4-62889 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz ED - Papadrakakis, Manolis T1 - Frequency-wavenumber method for the wave propagation through the soil and the soil-structure interaction of railway tracks and building foundations near railway lines N2 - In soil-structure interaction, the soil and the (flexible) structures are modelled as elastic continua. The partial differential equations of elasticity can be transformed to algebraic equations in frequency-wavenumber domain where they can be solved by matrix methods. The results for the soil and a structure can be coupled in frequency-wavenumber domain, and the solution in space domain is obtained by an infinite wavenumber integral (the back-transformation). This method has several applications for the prediction of the emission, transmission and immission of railway-induced vibrations. The wave propagation in homogeneous or layered soils is calculated for surface and tunnel lines by a single wavenumber integration (transmission). The response of ballast or slab tracks (for the emission problem) and the foundation stiffness (for the immission problem) need an additional integration across the track or foundation width. In wavenumber domain, tracks and foundations of infinite length are analysed. Finite structures can be calculated by finite element models where the soil is calculated by the boundary element method. The Green’s functions for the boundary element method are calculated by a wavenumber integration as for the transmission problem. Some example results for all these tasks will be shown. The immission into buildings will be analysed in detail, and the effect of stiff slab foundations and (basement) walls on the incoming wavefield is quantified in a parameter study. The transfer function (the amplitude ratio) structure to free field usually starts with 1 at 0 Hz and decreases continuously with frequency. The reduction is due to the structural stiffness against wave deformation which turns to be higher than the stiffness of the soil, for example above the structure-soil coincidence frequency of the slab foundation. The reduction is better for a high structural stiffness and for a low soil stiffness. Walls are stiffer than plates for the relevant frequency range, but even walls and especially low basement walls are not infinitely rigid and can follow the wave deformation to a certain extent. These basic rules from frequency-wavenumber analysis can well be used for real building projects near railway lines where stiff foundations can be an alternative reduction method to the commonly used base isolation by elastic elements. T2 - COMPDYN 2025 CY - Rhodos, Greece DA - 15.06.2025 KW - Frequency-wavenumber method KW - Wave propagation KW - Soil-structure interaction KW - Building foundations KW - Mitigation measures PY - 2025 SP - 1 EP - 15 PB - NTUA CY - Athen AN - OPUS4-63470 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz T1 - Frequency-wavenumber method for the wave propagation through the soil and the soil-structure interaction of railway tracks and building foundations near railway lines N2 - In soil-structure interaction, the soil and the (flexible) structures are modelled as elastic continua. The partial differential equations of elasticity can be transformed to algebraic equations in frequency-wavenumber domain where they can be solved by matrix methods. The results for the soil and a structure can be coupled in frequency-wavenumber domain, and the solution in space domain is obtained by an infinite wavenumber integral (the back-transformation). This method has several applications for the prediction of the emission, transmission and immission of railway-induced vibrations. The wave propagation in homogeneous or layered soils is calculated for surface and tunnel lines by a single wavenumber integration (transmission). The response of ballast or slab tracks (for the emission problem) and the foundation stiffness (for the immission problem) need an additional integration across the track or foundation width. In wavenumber domain, tracks and foundations of infinite length are analysed. Finite structures can be calculated by finite element models where the soil is calculated by the boundary element method. The Green’s functions for the boundary element method are calculated by a wavenumber integration as for the transmission problem. Some example results for all these tasks will be shown. The immission into buildings will be analysed in detail, and the effect of stiff slab foundations and (basement) walls on the incoming wavefield is quantified in a parameter study. The transfer function (the amplitude ratio) structure to free field usually starts with 1 at 0 Hz and decreases continuously with frequency. The reduction is due to the structural stiffness against wave deformation which turns to be higher than the stiffness of the soil, for example above the structure-soil coincidence frequency of the slab foundation. The reduction is better for a high structural stiffness and for a low soil stiffness. Walls are stiffer than plates for the relevant frequency range, but even walls and especially low basement walls are not infinitely rigid and can follow the wave deformation to a certain extent. These basic rules from frequency-wavenumber analysis can well be used for real building projects near railway lines where stiff foundations can be an alternative reduction method to the commonly used base isolation by elastic elements. T2 - COMPDYN 2025 CY - Rhodos, Greece DA - 15.06.2025 KW - Frequency-wavenumber method KW - Wave propagation KW - Soil-structure interaction KW - Building foundations KW - Mitigation measures PY - 2025 AN - OPUS4-63468 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - THES A1 - Wiehle, Philipp T1 - Einfluss der Feuchtigkeit auf das Tragverhalten von Lehmmauerwerk N2 - Im Mittelpunkt der vorliegenden Arbeit steht der Einfluss der Feuchte auf die mechanischen Eigenschaften von Lehmmauerwerk. Der Wissensstand zum feuchteabhängigen Tragverhalten von Lehm(mauerwerk) ist bisher lückenhaft, sodass keine explizite Berücksichtigung der Bauteilfeuchte bei der Bemessung tragender Konstruktionen erfolgt. Aktuelle und verlässliche Daten zum Einfluss der Feuchte auf die mechanischen Kenngrößen moderner Lehmbaustoffe fehlen bisher ebenso wie Messwerte in Bezug auf die Bauteilfeuchte unter natürlichen Klimabedingungen. Deswegen wurden im Rahmen dieser Arbeit umfangreiche Untersuchungen zum mechanischen und hygrothermischen Verhalten von Lehmmauerwerk durchgeführt. Die experimentellen Untersuchungen bestehen im Wesentlichen aus Druckversuchen an Lehmsteinen, -mörteln, kleinformatigen Lehmmauerwerksprobekörpern und geschosshohen Lehmmauerwerkswänden. Um das Feuchteverhalten beschreiben zu können, fanden außerdem erstmalig magnetresonanzspektroskopische Messungen an Lehmsteinen statt und es wurden die tatsächlich auftretenden Feuchtegehalte an einer Lehmmauerwerkswand unter natürlichen Klimabedingungen in Form von Langezeitmessungen ermittelt. Es konnte festgestellt werden, dass ein linearer Zusammenhang zwischen Druckfestigkeit und relativer Luftfeuchte besteht, wobei sich die Druckfestigkeit umgekehrt proportional zur relativen Luftfeuchte verhält. Je Prozent Steigerung der relativen Luftfeuchte kommt es zur Abnahme von einem Prozent der Druckfestigkeit. Gleiches gilt für das Elastizitätsmodul. Weiterhin konnte auf Basis der feuchtetechnischen Untersuchungen ein numerisches Modell zur Berechnung des instationären hygrothermischen Verhaltens für Lehmbaustoffe kalibriert werden. Anhand dieses Modells gelang es die bemessungsrelevanten Feuchtegehalte unter Berücksichtigung des instationären hygrothermischen Verhaltens realitätsnah zu berechnen. Die maximalen Feuchtegehalte im Lehmmauerwerk konnten somit in Form einer Parameterstudie in Abhängigkeit des Anwendungsfalls ermittelt werden, wodurch eine explizite Berücksichtigung des Feuchtegehaltes bei der Bemessung ermöglicht wurde. Die Verknüpfung der Erkenntnisse aus den mechanischen und hygrothermischen Untersuchungen dieser Arbeit bildet die Grundlage für das Bemessungskonzept der im Juni 2023 veröffentlichten DIN 18940: Tagendes Lehmsteinmauerwerk. KW - NMR KW - Lehm KW - Mauerwerk KW - Druckfestigkeit KW - Feuchtigkeit PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-637794 DO - https://doi.org/10.14279/depositonce-20800 SP - 1 EP - 114 CY - Berlin AN - OPUS4-63779 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wiehle, Philipp A1 - Baier, Johanna A1 - Thiele, Marc T1 - Structural Design of Earth Masonry in Accordance with Eurocode 6 – Considering Moisture Content and E/fk Ratio N2 - The load‐bearing behaviour of earth masonry is similar to conventional masonry, with two key differences: compressive strength and Young's modulus are dependent on moisture content, and the ratio between Young's modulus and characteristic compressive strength (E/fk) is significantly lower. The current design concept according to the Lehmbau Regeln does not explicitly address these factors, relying instead on a general safety margin, leading to an underestimation of the load‐bearing capacity of modern earth masonry.Compression tests on small‐scale masonry specimens and storey‐high walls revealed that compressive strength and Young's modulus decrease inversely proportional to the increase in relative humidity. Additionally, it was found that conventional masonry design guidelines overestimate the buckling resistance of earth masonry due to its low E/fk ratio of ∼440. However, this ratio remains independent of moisture content, simplifying structural design, as the load‐bearing capacity is only influenced by wall slenderness.The study's findings form the foundation for the newly published German design standard DIN 18940, which explicitly considers moisture content through service classes with moisture factors and addresses the low E/fk ratio with a bilinear adaptation of the reduction factor considering the slenderness. Along with the introduction of the semi‐probabilistic design concept and rigid‐plastic determination of cross‐sectional load‐bearing capacity, modern earth masonry can now be applied in buildings up to four storeys. T2 - Earth Builder Summit CY - Biberach, Germany DA - 06.03.2025 KW - Service class KW - Earth masonry KW - Structural design KW - Moisture PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-637803 DO - https://doi.org/10.1002/cepa.3287 SN - 2509-7075 VL - 8 IS - 1 SP - 9 EP - 21 PB - Ernst & Sohn GmbH AN - OPUS4-63780 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz A1 - Said, Samir A1 - Rohrmann, Rolf ED - Döhler, Michael T1 - Modal analysis of road and rail bridges for damage detection and resonance prediction N2 - In the 1980s, the Federal Institute of Material Research and Testing started with modal analysis measurements of some bridges before and after repair. For one of the bridges, a structural health monitoring was installed 1994 which is still working up to now. It has been modified and extended several times. The monitoring was extended from the critical span to three neighbouring spans. A modal analysis of the whole bridge with seven spans have been done three times, twice together with EMPA of Switzerland. Additional calibration measurements have been done and additional evaluation procedures have been implemented for the monitoring of the steadily increasing loads from the road traffic. Additional sensors were installed such as strain gauges, crack-width, and temperature sensors. The strong influence of the temperature on the natural frequencies has been studied over the years. Later, a temperature compensation has been established and a weak aging trend has been found in the monitoring data. Now, the bridge will be demolished and replaced by a new bridge. Some results of this long-term monitoring will be shown and possible damages (changes of the pre-stress or the support structure) will be discussed. A second application of modal analysis will be demonstrated: the prediction of the resonances due to passing trains. The response of a bridge to passing trains can be calculated in frequency domain as the multiplication of three spectra, the axle sequence spectrum of the train, the transfer function of the bridge, and the modal force spectrum of a single passing load. A resonance occurs if a maximum of the train spectrum coincides with the maximum of the bridge spectrum. The amplitude at this resonance is strongly influenced by the modal force spectrum which is identical to the frequency or wavenumber spectrum of the corresponding mode shape. Therefore, modal analysis from calculation, impact measurements, wind and train measurements are necessary for the prediction of the resonance occurrence and amplification. Examples of mode shape spectra for single or multi-span bridges with simply supported or continuous spans will be shown, and some relations between mode shapes and resonance amplifications will be concluded. T2 - 11th International Operational Modal Analysis Conference (IOMAC) CY - Rennes, France DA - 20.05.2025 KW - Bridge monitoring KW - Multi-span bridges KW - Damage detection KW - Resonance PY - 2025 SP - 1 EP - 8 PB - INRIA CY - Rennes AN - OPUS4-63473 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Agasty, Amit T1 - Structural behavior and damage assessment of a reinforced concrete wall by various NDT methods and embedded sensors under blast-loading N2 - A safety or security related assessment of explosions, accidental and intentional scenarios alike, often necessitate performance of replication-tests. Such test results are necessary to clarify the causes within the scope of forensic investigations. To gain important insights into the behavior of structures and materials under such loading, field tests may also be performed in accordance with different test standards. To determine the resistance of building-structures after explosions, estimation of the residual load-bearing capacity in addition to the assessment of dynamic structural response and damage to the building components is important. In most cases an evaluation of structural integrity is based only on the visual damage, resulting in an overestimation of the residual capacity. The Bundesanstalt für Materialforschung und -prüfung (BAM) operates the Test site for Technical Safety (TTS) on an area measuring about 12 km2 in the Federal State of Brandenburg for execution of true-to-scale explosion tests. At the TTS, building component testing was performed to assess the suitability of different non-destructive testing methods to characterize the dynamic structural response and damage resulting from the detonation of high explosives. Different blast-loading scenarios were realized by varying the net explosive mass and the standoff distance with all scenarios representing a near-field detonation. The test object was a reinforced concrete wall 2 m high, 2.5 m wide and 20 cm thick, fixed at both vertical edges. The dynamic loading of the wall was characterized with 8 piezoelectric pressure sensors flush-mounted on the front surface, thus measuring the reflected pressures from the shock wave. The tests were conducted with the aim of characterizing the global behavior of the wall under dynamic shock loading and the resulting local damage pattern, respectively. High speed digital image correlation was implemented in combination with multiple acceleration sensors to observe the rear surface of the wall to chart the dynamic deflection during the loading and to determine the residual deformation after the loading had ceased. In addition, one test specimen was instrumented with fiber optic sensor cables, both fixed to the rebars and embedded in the concrete-matrix, respectively. Firstly, these sensors were interrogated during the blast test by a distributed acoustic sensing (DAS) device using a particularly high sampling rate to measure the shock-induced vibrations in the structure with high temporal resolution. This delivers information on dynamics of compression and tension cycles from within the structure. Secondly, the local damage-pattern emerging during the series of blasts was determined via distributed fiber optic strain sensing (DSS) by interrogating the embedded fiber optic sensors with a high spatial resolution DSS device after each blast. This enabled the characterization of non-visual damage to the structure, in particular with regard to the formation of localized cracks in the concrete matrix. The DSS was further complimented by a structure-scanner based on ultrasonic measurements. Our contribution describes this new test approach in detail. Results of the three datasets, namely dynamic shock loading, global behavior of the test object and the local damage pattern will be presented. The suitability of the implemented measurement methods will be discussed in combination with the challenges in their application for technical safety evaluation of building components under explosive loading. T2 - 26th International Symposium on Military Aspects of Blast and Shock (MABS26) CY - Wollongong, Australia DA - 03.12.2023 KW - Blast tests KW - Reflected pressure KW - Embedded sensors KW - Distributed fiber optic sensors KW - Acceleration sensors KW - Digital image correlation KW - Ultrasonic structure-scanner PY - 2023 AN - OPUS4-58927 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz T1 - Prediction of ground vibrations from rail tunnels finite element, boundary element and wavenumber calculations N2 - The prediction of ground and building vibrations has been established for surface lines and has now been extended to tunnel lines. The wave propagation in homogeneous or layered soils (the transmission) is calculated by an integration in wavenumber domain. The wave amplitudes at different distances and for different frequencies will be analysed for the following situations. 1. The horizontal propagation from a surface point to a surface point constitutes the basic rules. 2. The horizontal propagation from a source point at depth to a receiver point at depth which is related to a building with a deep basement or on a pile foundation. 3. The propagation from depth to the surface, which is the normal case for free-field measurements, has some different characteristics, for example a weaker attenuation with the horizontal distance from the source, which can be approximated by the full-space solution and the reflection rules for incident waves. The emission from a tunnel structure has been calculated by a finite-element model of the tunnel combined with a boundary-element model of the soil giving the reduction compared to a point-load excitation. The immission has been analysed by finite-element models of tunnel-soil-building systems for examples of research and consultancy work. Measurement results from a high-speed and a metro line confirm some of the established rules. T2 - Recent Advance in Structural Dynamics (RASD) CY - Southampton, UK DA - 01.07.2024 KW - Ground vibration KW - Building vibration KW - Railway tunnel KW - Wavenumber method KW - Finite element method KW - Boundary element method PY - 2024 AN - OPUS4-61230 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bednarska, Dalia A1 - Wieczorek, Alicja A1 - von Werder, Julia T1 - A novel methodology for indirect application of hydrophobic agents into cement matrix: Superabsorbent polymers (SAPs) as a delivery medium N2 - Hydrophobic agents are one of the most commonly used means of prolonging the lifespan of cement-based materials. However, when water-repellent is added to the batch water it can interfere with cement hydration leading to deteriorated mechanical properties of the hardened material. To eliminate this drawback, a novel methodology of indirectly applying hydrophobic agents to cement-based materials is introduced. The presented approach uses super absorbent polymers (SAPs) as a delivery medium. SAP containing water-repellent is added to the fresh cement mixture, which ensures a gradual release of the admixture. The release is driven either by drying which generates moisture gradient or by compression of polymer particles by hydrates arising in their vicinity. Such mechanisms lead to a delayed dosage of the hydrophobic agent, which is when the partially hardened cement matrix is less vulnerable to interference compared to the fresh mixture. The effectiveness of the proposed methodology was verified in the extensive experimental program. Cement mortars of two water-to-cement ratios (0.4, and 0.5) were tested in terms of compressive strength, capillary absorption, and contact angle among others. Based on the obtained results it is concluded that the proposed methodology limits the negative impact of the hydrophobic agent on cement hydration. The mechanical performance of the samples modified with the indirectly dosed admixture is improved compared to the conventionally hydrophobized material in each analysed case. The results of isothermal calorimetry support the thesis. Additionally, the effectiveness of imparting hydrophobic characteristics to the cement matrix was as good as in the case of the conventional dosing. The mercury intrusion porosimetry, as well as thermogravimetric tests, were run to provide a deeper insight into the microstructure and composition of the modified material. Scanning electron microscopy was used to give a better insight into samples’ morphology. The novel methodology presented can also potentially be used to dose other types of admixtures that can interfere with cement hydration. KW - Super absorbent polymers KW - Cement mortar KW - Hydrophobic admixture KW - Hydrophobization KW - Capillary absorption KW - Thermal analysis PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-637701 DO - https://doi.org/10.1016/j.cscm.2025.e04935 SN - 2214-5095 VL - 23 SP - 1 EP - 23 PB - Elsevier Ltd. AN - OPUS4-63770 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Artinov, Antoni T1 - Fracture Mechanics-Based Approach for Fatigue Life Assessment of Welded Structures: The Role of Real Weld Geometries and Welding Residual Stresses N2 - Fatigue failure is a critical concern in offshore wind structures, where welded joints are subjected to cyclic loading over extended service lifetimes. The combined effects of weld geometry [1, 2] and welding residual stresses (WRS) significantly influence the fatigue strength of welds [3-5]. In offshore wind applications, fatigue behavior is further complicated by cyclic loading conditions, where externally applied loads from wind, waves, and ocean currents interact with WRS, causing localized plastic deformation due to high-stress concentrations. Additionally, under prolonged cyclic loading, the redistribution of WRS can result in a shift of the fatigue-prone regions over time, meaning that locations identified as high-risk may not remain the dominant failure sites throughout the structure’s service life [6]. This presents a significant challenge for inspection and maintenance strategies, as conventional monitoring approaches may fail to detect the most vulnerable zones at later stages of operation. Early experimental studies on low-carbon steel plates and butt joints have shown that tensile WRS can reduce fatigue limits by up to 50% compared to stress-relieved specimens [7]. This effect is particularly pronounced in regions with welding defects, such as porosity, lack of fusion, and undercuts, as well as at geometric discontinuities, including weld toes and sharp notches, which induce localized stress gradients. The combined effect of tensile WRS and stress concentrations amplifies the local stress fields, promoting crack initiation and accelerating crack propagation, ultimately reducing the service life of offshore wind structures. Despite the critical role of weld geometry and WRS in fatigue performance, conventional fatigue assessment methods frequently neglect or oversimplify their effects, leading to overly conservative predictions and suboptimal structural designs. Current engineering standards, including BS 7910 (2019), BS 7608 (1993), EN 13001-3-1 (2020), and EN 1993-1-9 (2013), assume high tensile WRS in welded joints and apply simplified fatigue life prediction approaches that eliminate the need for explicit mean stress considerations. While some standards introduce correction factors for different WRS states, these remain highly generalized and lack accuracy. More sophisticated approaches, such as the Integrated Approach to Fatigue Strength Determination of Welded Structures (IBESS) [8], attempt to incorporate WRS into fatigue life assessments but rely on effective load ratios rather than explicitly modeling and considering real WRS distributions in the analysis. Additionally, IBESS does not fully integrate real weld geometries, limiting its predictive accuracy. These limitations result in significant scatter in fatigue life predictions, excessive conservatism, and inefficiencies in structural design. Although existing fatigue models improve on traditional methodologies, to the best of the authors' knowledge a unified framework that fully captures the combined effects of real weld geometries, WRS, and cyclic loading does not exist yet. The present research aims to develop an advanced fracture mechanics-based numerical framework for fatigue life assessment that explicitly accounts for these influencing factors at the specimen level, establishing the foundation for future scaling to component-level applications. T2 - Wind Energy Science Conference CY - Nantes, France DA - 23.06.2025 KW - Fatigue Assessment KW - Wind Offshore Structures KW - Fracture Mechanics KW - Digital Weld Geometries KW - Welding Residual Stresses KW - Numerical Modeling PY - 2025 AN - OPUS4-63591 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kemmler, Samuel T1 - Fully-resolved LBM-DEM simulations of piping erosion during a suction bucket installation N2 - Suction bucket foundations are a cost-efficient and environmentally sustainable solution to install offshore wind turbines, achieved through the application of growing suction pressure inside the bucket until its full embedment into the seabed. A key challenge for the installation process is the occurrence of piping erosion, a phenomenon where fluidization of particles beneath the bucket wall tip causes a drop in suction pressure, potentially leading to installation failure. Despite its significance, the complex physical mechanisms driving piping erosion remain insufficiently understood. To address this knowledge gap, a three-dimensional, fully-resolved coupled LBM-DEM simulation is employed to conduct an in-depth analysis of piping erosion, aiming to identify key influencing parameters, thus enhancing understanding and optimizing the installation process. The simulation of physically relevant problem sizes - comprising hundreds of thousands of grains - is equivalent to computational intensities which demand for extensive computational resources. Results from simulations executed on hundreds of GPUs on the LUMI supercomputer are presented, illustrating the method's capability to tackle this complex challenge. T2 - 10th International Conference on Discrete Element Methods CY - Himeji, Japan DA - 01.07.2025 KW - Offshore wind support structure KW - Suction bucket foundation KW - Piping erosion KW - Micromechanical simulation PY - 2025 AN - OPUS4-63691 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Costard, Rene A1 - Hering, Marcus T1 - Explosionsauswirkungen auf Strukturen N2 - Wir berichten über die Entwicklungen des AP2 im Hinblick auf Explosionsauswirkungen auf Strukturen und den Weg zur systematischen messtechnischen Erfassung zur ganzheitlichen Bewertung der Bauwerksicherheit unter Detonationsbelastung. Zusätzlich werden die Vorführungen zu Kontaktdetonationen während der 16. Informationsveanstaltung Sprengstoffe und Pyrotechnik vorgeführt. T2 - 16. Informationsveranstaltung Sprengstoffe und Pyrotechnik CY - Berlin, Germany DA - 20.05.2025 KW - Explosion KW - Kontaktdetonation KW - Blast PY - 2025 AN - OPUS4-63192 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz T1 - Railway-induced ground and building vibrations – Analysis in frequency-wavenumber domain and fast prediction with approximate models N2 - A simple and fast prediction scheme is presented for train-induced ground and building vibrations. For the emission, finite-element boundary-element or multiple-beam-on-continuous-soil models of the track have been analysed and approximated by faster track-on-Winkler-soil models. The vehicle-track interaction due to irregularities yields the excitation forces. For the transmission of waves in the soil, the wavenumber integral of the compliance of layered soils has been evaluated. The calculation time is reduced for the prediction by using the solution of a homogeneous half-space with a frequency-dependent wave velocity (the dispersion) of the soil. For the immision, many 2 and 3-dimenisonal finite-element building models have been investigated, and a good approximation has been established by a 1-dimensional soil-wall-floor model. In addition, the axle sequence of the train, the quasi-static and the “scattered” response of the soil, and the wave propagation from a tunnel to a pile foundation of a building have been included. T2 - ISMA-Conference 2022 CY - Leuven, Belgium DA - 12.09.2022 KW - Ground vibration KW - Simple prediction KW - Vehicle-track interaction KW - Layered soil KW - Soil-building interaction KW - Soil-wall-floor model KW - Propagation from a tunnel KW - Tunnel-pile transfer PY - 2022 SP - 1 EP - 13 PB - KU Leuven CY - Leuven AN - OPUS4-56603 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz A1 - Said, Samir A1 - Rohrmann, R. T1 - Measurement and evaluation tools for ground and building vibrations from industrial pro-cesses, construction work, traffic and other sources N2 - Vibration measurements have many causes and many technical and natural sources. Problems can sometimes be solved by short-term measurements, but in many cases, a long-term measurement is necessary. In long-term measurements of days, weeks, months and even years, it is easy to collect a huge quantity of raw data, but at the end, the post-processing of these data can be exhausting (for example one-year vibration data of a wind energy tower). A software has been developed which con-sists of measuring and evaluation routines where the measuring routines can operate different meas-uring systems and different measuring cards. The main advantage of this software is the fact that the interesting evaluations can be integrated in the measuring process so that the characteristics of the vibration can be extracted without storing all the raw data. Only important time segments are stored, for example train passages. The overall concept of the software and the main evaluation routines will be described in some details. Examples of our measurement experience will illustrate the capabilities of the software. 1) Surveying construction work in nearby sensitive buildings (for example an old wind tunnel), including a stable alarm system and meaningful vibration limits. 2) Prediction of train-induced vibration for a planned building to prevent annoyance and to improve the building design. 3) Modal analysis and long term measurements of several single- or multi-span, concrete or steel bridges 4) Modal and wave analysis of coupled floors in a historical building (“Neues Palais” at Potsdam). 5) Soil properties of various measurement sites (different routines to evaluate the dispersion). Moreover, from many projects, amplitudes, frequencies, and attenuation laws have been collected and analysed for the different sources such as vibratory or impact pile driving and ground compaction, demolition work with different machines, blasting in quarries and in tunnel works, bomb and mine clearing. T2 - 28th International Congress on Sound and Vibration CY - Online meeting DA - 24.07.2022 KW - Ground vibration KW - Building vibration KW - Measurement KW - Evaluation KW - Modes KW - Waves PY - 2022 SP - 1 EP - 8 AN - OPUS4-56602 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz T1 - Effects of a varying track and soil stiffness on ground vibrations near railway lines N2 - Usually, geometric irregularities are considered as the main cause of ground vibrations from trains. A varying stiffness of the track, the track support and the soil can also generate ground vibrations. The regular stiffness variation of the track on and between the sleepers results in a deterministic dynamic axle load. The random stiffness variation of the track support yields also dynamic axle loads which are generated by the acceleration of the unsprung mass (from the varying wheel displacements under the static axle load). The random stiffness variation has a second effect. The pulses from the passage of the static axle loads are superposed regularly to the quasi-static response, but also irregularly to yield a “scattered” part of the axle pulses. The same holds for a random variation of the soil stiffness. All these effects of stiffness variations have been calculated by wavenumber-domain multi-beam track models, a random finite-element soil model and the superposition of axle impulses in a stochastic simulation. The results are confronted with many measurements at different sites. It is concluded that the stiffness variation of the track and the soil generate an important ground vibration component near railway lines. T2 - International Conference Railways 2022 CY - Montpellier, France DA - 22.08.2022 KW - Ground vibration KW - Axle loads KW - Irregularities KW - Varying stiffness PY - 2022 SP - 1 EP - 11 AN - OPUS4-56605 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz T1 - Die Einfügedämmung bei Schienenfahrwegen Definition, Messung und Berechnung N2 - Die Definition und Beschreibung der Einfügedämmung im Normentwurf DIN 45673-4 ist noch nicht richtig. Es wird die Beschreibung aus DIN 45673-3 herangezogen, die für Messungen gilt. Für die drei Rechenverfahren gibt es jeweils eine passende Beschreibung. Mit diesen Vorlagen ist eine vernünftige Definition der Einfügungsdämmung zu finden. Es bedarf einer Abgrenzung gegenüber anderen (falschen) Möglichkeiten. Des Weiteren ist der Anhang 2 erweitert und der Parametersatz im Anhang 1 auf das Wesentliche reduziert worden. T2 - Norm-Arbeitsausschuss Schwingungsminderung in der Umgebung von Verkehrswegen CY - Online meeting DA - 14.12.2022 KW - Einfügungsdämmung KW - Schienenfahrwege KW - Kraft auf den Boden KW - Erschütterungen im Fernfeld PY - 2022 AN - OPUS4-56601 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz T1 - Prognoseverfahren für Bahnerschütterungen – DIN 45672-3, VDI 3837, HighSpeed2 und die Fahrzeug-Fahrweg-Boden Wechselwirkung N2 - Die VDI Richtlinie 3837 enthält detaillierte Angaben zur Erschütterungsemission. Die DIN 45672-3 enthält nur den Tunnel- oder einen Bodenmesspunkt als Ausgangspunkt der Prognose. Die Erschütterungsanregung durch die Fahrzeug-Fahrweg-Wechselwirkung wird beschrieben. Die ERgebnisse der BAM stimmen sehr gut mit dem Prognosekonzept von Highspeed 2 überein. Dies wird an den Punkten 1. Störgrößen, 2. Achsimpulse, 3. Tunnelstrecken aufgezeigt. T2 - Norm-Arbeitsausschuss Schwingungsminderung in der Umgebung von Verkehrswegen CY - Frankfurt/M., Germany DA - 08.02.2023 KW - Normung KW - Bahnerschütterungen KW - Emission KW - Fahrzeug-Fahrweg-Boden-Wechselwirkung KW - Störgrößen KW - Achsimpulse KW - Tunnelstrecke PY - 2023 AN - OPUS4-56978 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Auersch, Lutz T1 - The dynamic train-track interaction on a bridge and in a tunnel compared with the simultaneous vehicle, track, and ground vibration measurements at a surface line N2 - The vehicle–track interaction generates forces and consequently vibrations in the environment. The interaction has been analysed by the simultaneous measurements of vehicle, track and ground vibrations during test runs with varied train speeds. The special effects of the passage over a bridge and through a tunnel are studied and compared with the measurements on a conventional ballasted surface line. The maximum amplitudes, narrow band and one-third octave band spectra are presented for the axle-box accelerations and for the track, bridge and ground vibrations. The different frequencies and frequency bands are related to wheel out-of-roundness, track alignment errors, the sleeper passage and the wheelset–track resonance. An axle impulse component has been observed at the track, at the near-field soil and as a scattered version in the far field. Specific results can be found for the bridge track, where clearly speed-dependent bridge resonances occur due to the axle sequence of the train, and for the tunnel track where soft rail pads are responsible for a strong amplification around the wheelset–track resonance. On the other hand, the axle impulses are strongly reduced by the tunnel track, and the scattered axle impulse component is not as relevant as for the surface track. As a consequence, a strong mid-frequency amplitude reduction of the tunnel compared to the surface line has been measured for low and high train speeds by the Federal Institute of Material Research and Testing (BAM) and by other institutes. KW - Vehicle–track interaction KW - Ground vibration KW - Tunnel-to-surface reduction KW - Bridge resonance KW - Axle sequence PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-585139 DO - https://doi.org/10.3390/app131910992 VL - 13 IS - 19 SP - 1 EP - 23 PB - MDPI CY - Basel, Schweiz AN - OPUS4-58513 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Auersch, Lutz T1 - Soil–structure interaction and damping by the soil - effects of foundation groups, foundation flexibility, soil stiffness and layers N2 - In many tasks of railway vibration, the structure, that is, the track, a bridge, and a nearby building and its floors, is coupled to the soil, and the soil–structure interaction and the damping by the soil should be included in the analysis to obtain realistic resonance frequencies and amplitudes. The stiffness and damping of a variety of foundations is calculated by an indirect boundary element method which uses fundamental solutions, is meshless, uses collocation points on the boundary, and solves the singularity by an appropriate averaging over a part of the surface. The boundary element method is coupled with the finite element method in the case of flexible foundations such as beams, plates, piles, and railway tracks. The results, the frequency-dependent stiffness and damping of single and groups of rigid foundations on homogeneous and layered soil and the amplitude and phase of the dynamic compliance of flexible foundations, show that the simple constant stiffness and damping values of a rigid footing on homogeneous soil are often misleading and do not represent well the reality. The damping may be higher in some special cases, but, in most cases, the damping is lower than expected fromthe simple theory. Some applications and measurements demonstrate the importance of the correct damping by the soil. KW - Soil–structure interaction KW - Soil dynamics KW - Radiation damping of the soil KW - Rigid foundation KW - Flexible foundation KW - Foundation groups KW - Boundary element method KW - Vibration measurement PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-627007 DO - https://doi.org/10.3390/vibration8010005 SN - 2571-631X VL - 8 IS - 5 SP - 1 EP - 28 PB - MDPI CY - Basel, Schweiz AN - OPUS4-62700 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Auersch, Lutz T1 - Prediction of ground vibrations from rail tunnels –finite-element, boundary-element and wavenumber calculations N2 - The prediction of ground and building vibrations has been established for surface lines and has now been extended to tunnel lines. The wave propagation in homogeneous or layered soils (the transmission) is calculated by an integration in wavenumber domain. The wave amplitudes at different distances and for different frequencies will be analysed for the following situations. 1. The horizontal propagation from a surface point to a surface point constitutes the basic rules. 2. The horizontal propagation from a source point at depth to a receiver point at depth which is related to a building with a deep basement or on a pile foundation. 3. The propagation from depth to the surface, which is the normal case for free-field measurements, has some different characteristics, for example a weaker attenuation with the horizontal distance from the source, which can be approximated by the full-space solution and the reflection rules for incident waves. The emission from a tunnel structure has been calculated by a finite-element model of the tunnel combined with a boundary-element model of the soil giving the reduction compared to a point-load excitation. The immission has been analysed by finite-element models of tunnel-soil-building systems for examples of research and consultancy work. Measurement results from a high-speed and a metro line confirm some of the established rules. KW - Railway tunnel KW - Ground vibration KW - Building vibration KW - Wavenumber integral KW - Full-space solution KW - Reflection at the surface PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-627015 DO - https://doi.org/10.1088/1742-6596/2909/1/012013 SN - 1742-6596 VL - 2909 SP - 1 EP - 12 PB - IOP Publishing CY - London AN - OPUS4-62701 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Peters, Simon A1 - Pittrich, Tim A1 - Stelzner, Ludwig A1 - Weise, Frank A1 - Meschke, Günther T1 - Concretes containing blended-cements with reduced carbon-dioxide emissions: A chemo-thermo-hygro-mechanical model for elevated temperatures N2 - A comprehensive analysis aimed at understanding and assessing the high-temperature behavior of concretes containing blended cements (CEM III/A, CEM II/B-Q, and CEM IV), characterized by low carbon-dioxide emissions (during clinker’s production) is necessary to reliably model the damage in the concrete, thermal spalling included. To this purpose, a numerical chemo-thermo-hygro-mechanical model is formulated, to investigate – among other phenomena – heat transmission and pore pressure for different aggregate types. Based on an available hydration model, a dehydration model is established to numerically investigate the evolution of dehydration and porosity at elevated temperatures. Based on the properties of concrete and cement constituents on multiple scales, an analytical homogenization process is proposed to predict the thermal conductivity of the concrete. This process is later validated and implemented into a macroscopic modeling framework. Chemo-thermo-hygro-mechanical analyses show that the dehydration characteristics of blended low carbon-dioxide release cements may increase pore pressure in the concrete by up to 13% compared to the concrete containing ordinary Portland cement. In addition, aggregates exhibiting high thermal conductivity may contribute to a further increase (even more than 35%) in pore pressure compared to aggregates with low thermal conductivity. Last but not least, the proposed model provides the basis for the reduction of the number of the parameters commonly required in the chemo-thermo-hygro-mechanical modeling of cementitious materials. KW - Concrete at high temperature KW - Dehydration KW - Multiscale modeling KW - Thermal conductivity KW - Chemo-hygro-thermal analysis KW - Micromechanics PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-635894 DO - https://doi.org/10.1016/j.cemconcomp.2025.106163 SN - 0958-9465 VL - 163 SP - 1 EP - 17 PB - Elsevier Ltd. AN - OPUS4-63589 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Marx, S. A1 - Scheerer, S. A1 - Schacht, G. A1 - Fiedler, M. A1 - Ritter, R. A1 - Clages, L. A1 - Voigt, C. A1 - Czeschka, D. A1 - Ebell, Gino A1 - Marzahn, G. T1 - Einsturz der Carolabrücke in Dresden Teil 1 T1 - Collapse of the Carola Bridge in Dresden Part 1: From theambitious design to the tragic partial collapse N2 - AbstraktDer 11. September 2024 wird nicht nur der Brückenbaucommunity in Deutschland in Erinnerung bleiben. Der Teileinsturz einer Spannbetonbrücke ohne Vorankündigung schlug berechtigterweise gesamtgesellschaftlich hohe Wellen. Betroffen war die Dresdner Carolabrücke – ein ästhetisches und ausgesprochen schlankes Bauwerk, welches in der Fachwelt zurecht als eine Ikone der Ingenieurbaukunst ihrer Zeit angesehen wird. Die Konstruktion sowie der Bau wären auch unter den heutigen Möglichkeiten eine Herausforderung. Der vorliegende Teil 1 des Beitrags fasst die Entstehungsgeschichte, die Konstruktion selbst und den Bau der Brücke zusammen. Es werden die Maßnahmen zur Instandhaltung und Sanierung der Brücke vorgestellt. In einem Teil 2 wird der Versuch der Rekonstruktion des Einsturzvorgangs unternommen und die Suche nach der Einsturzursache beschrieben. Zudem wird auf das aktuelle Monitoring eingegangen und ein Ausblick auf das mögliche weitere Vorgehen gegeben. KW - Korrosion KW - Spannungsrisskorrosion KW - Spannstahl KW - Wasserstoff PY - 2025 DO - https://doi.org/10.1002/best.202500029 SN - 0005-9900 VL - 120 IS - 7 SP - 526 EP - 536 PB - Wiley AN - OPUS4-63411 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz T1 - Modal analysis of road and rail bridges for damage detection and resonance prediction N2 - In the 1980s, the Federal Institute of Material Research and Testing started with modal analysis measurements of some bridges before and after repair. For one of the bridges, a structural health monitoring was installed 1994 which is still working up to now. It has been modified and extended several times. The monitoring was extended from the critical span to three neighbouring spans. A modal analysis of the whole bridge with seven spans have been done three times, twice together with EMPA of Switzerland. Additional calibration measurements have been done and additional evaluation procedures have been implemented for the monitoring of the steadily increasing loads from the road traffic. Additional sensors were installed such as strain gauges, crack-width, and temperature sensors. The strong influence of the temperature on the natural frequencies has been studied over the years. Later, a temperature compensation has been established and a weak aging trend has been found in the monitoring data. Now, the bridge will be demolished and replaced by a new bridge. Some results of this long-term monitoring will be shown and possible damages (changes of the pre-stress or the support structure) will be discussed. A second application of modal analysis will be demonstrated: the prediction of the resonances due to passing trains. The response of a bridge to passing trains can be calculated in frequency domain as the multiplication of three spectra, the axle sequence spectrum of the train, the transfer function of the bridge, and the modal force spectrum of a single passing load. A resonance occurs if a maximum of the train spectrum coincides with the maximum of the bridge spectrum. The amplitude at this resonance is strongly influenced by the modal force spectrum which is identical to the frequency or wavenumber spectrum of the corresponding mode shape. Therefore, modal analysis from calculation, impact measurements, wind and train measurements are necessary for the prediction of the resonance occurrence and amplification. Examples of mode shape spectra for single or multi-span bridges with simply supported or continuous spans will be shown, and some relations between mode shapes and resonance amplifications will be concluded. T2 - 11th International Operational Modal Analysis Conference (IOMAC) CY - Rennes, France DA - 20.05.2025 KW - Bridge monitoring KW - Multi-span bridges KW - Damage detection KW - Resonance PY - 2025 AN - OPUS4-63472 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Müller, Thoralf T1 - Bericht aus den DIN-Ausschüssen "Korrosionsprüfverfahren“ + „Korrosion und Korrosionsschutz“ N2 - Der Vortrag gibt einen Überblick über die Tätigkeiten der DIN-Ausschüsse "Korrosionsprüfverfahren" sowie "Korrosion und Korrosionsschutz". Es werden neuste Informationen zum Stand verschiedener Normen aus den beiden Ausschüssen gegeben. T2 - Gemeinschaftssitzung der GfKorr-Arbeitskreise "Korrosion und Korrosionsschutz von Aluminium und Magnesium" und "Korrosionsuntersuchung und -überwachung" CY - Magdeburg, Germany DA - 11.04.2019 KW - Normen KW - Korrosionsschutz KW - Korrosion KW - Korrosionsprüfung PY - 2019 AN - OPUS4-47980 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Müller, Thoralf T1 - Korrosionsschutzmethoden N2 - Der Vortrag thematisiert die Grundlagen des Korrosionsschutzes. Dieser kann planungs-,werkstoff oder mediumsseitig erfolgen oder mit elektrochemischen Methoden umgesetzt werden. Der Vortrag beschreit die Korrosivitäten der Atmosphären und welche Maßnahmen für den Korrosionsschutz daraus abgeleitet werden können. T2 - Fachausbildung Kathodischer Korrosionsschutz - Grundlagenkurs für erdverlegte Anlagen, Stahlbeton und Innenschutz CY - Technische Akademie Esslingen, Germany DA - 22.01.2019 KW - Korrosion KW - Korrosionsschutz KW - Passivität KW - Beschichtung KW - Überzüge KW - Kathodische Korrosionsschutz PY - 2019 AN - OPUS4-47273 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Müller, Thoralf T1 - Korrosion metallischer Werkstoffe N2 - Der Vortrag thematisiert die Grundlagen der Korrosion metallischer Werksoffe. Inhalt des Vortrags sind die Grundlagen zur Potentialbildung, die Teilreaktionen der Korrosionsreaktion, elektrochemische Versuche und deren Auswertung sowie die Grundlagen der Bimetallkorrosion T2 - Fachausbildung Kathodischer Korrosionsschutz - Grundlagenkurs für erdverlegte Anlagen, Stahlbeton und Innenschutz CY - Technische Akademie Esslingen, Germany DA - 22.01.2019 KW - Korrosion KW - Bimetallkorrosion KW - Potential KW - Elektrochemie PY - 2019 AN - OPUS4-47272 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Müller, Thoralf T1 - Korrsosion und Korrosionsschutz von technischen Anlagen N2 - Der Vortrag behandelt die Grundlagen der Korrosion sowie einzelene Aspekte von Korrosionsschutzmethoden. Weiterhin werden Themen wie Bimetallkorrosion und Spaltkorrosion erläutert. Es werden passivierbare Werkstoffe und deren Eigenschaften im Hinblick auf einen korrosionsschutzgerechten Einsatz vorgestellt. T2 - 13. VDE Fachtagung Blitzschutz CY - Dresden, Germany DA - 14.11.2019 KW - Korrosion KW - Bimetallkorrosion KW - Nichtrostender Stahl KW - Aluminium KW - Zink KW - Spaltkorrosion PY - 2019 AN - OPUS4-49760 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Müller, Thoralf T1 - Bericht aus den DIN Ausschüssen N2 - Der Vortrag gibt einen Überblick über die Tätigkeiten der DIN-Ausschüsse "Korrosionsprüfverfahren" sowie "Korrosion und Korrosionsschutz". Es werden neuste Informationen zum Stand verschiedener Normen aus den beiden Ausschüssen gegeben. T2 - GfKorr Gemeinschaftssitzung der Arbeitskreise "Korrosionsuntersuchung und -überwachung" und "Grundlagen der Korrosion" CY - Dusseldorf, Germany DA - 21.11.2019 KW - Korrosion KW - Korrosionsschutz KW - Normung KW - Korrosionsprüfung PY - 2019 AN - OPUS4-49761 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Wagner, Adrian T1 - Nichtrostender Stahl in Kontakt mit anderen Werkstoffen in wässrigen Medien und bei atmosphärischer Beanspruchung N2 - Der Vortrag behandelt das Thema Bimetallkorrosion und deren Einflussfaktoren an nichtrsotenden Stählen. Weiterhin werden die Korrosionseigenschaften von nichtrostenden Stählen in Kontakt mit alkalischen wie auch sauren Baustoffen näher beschrieben. T2 - VDEh Seminar "Korrosionsverhalten nichtrostender Stähle in wässrigen Medien und bei atmosphärischer Beanspruchung" CY - Düsseldorf, Germany DA - 03.12.2019 KW - Nichtrostender Stahl KW - Korrosion KW - Bimetallkorrosion KW - Kontaktkorrosion PY - 2019 AN - OPUS4-49944 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Müller, Thoralf T1 - Korrosionsprüfung N2 - Der Vortrag gibt einen Überblick über gängige Korrosionsprüf- und -untersuchungsverfahren. Es werden Auslagerungsversuche sowie Korrosionskammerprüfungen vorgestellt sowie elektrochemische Messmethoden zur Bestimmung der Korrosionsbeständigkeit. T2 - VDEh Seminar "Korrosionsverhalten nichtrostender Stähle in wässrigen Medien und bei atmosphärischer Beanspruchung" CY - Düsseldorf, Germany DA - 03.12.2019 KW - Nichtrostender Stahl KW - Korrosion KW - Korrosionsprüfung PY - 2019 AN - OPUS4-49946 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Müller, Thoralf A1 - Ebell, Gino A1 - Burkert, Andreas T1 - Risiko der Wasserstoffentwicklung an martensitischen Schraubankern unter baupraktischen Bedingungen T1 - Risk of hydrogen evolution on martensitic screw anchors under practical construction conditions N2 - Die vorliegende Untersuchung beschäftigt sich mit der Fragestellung, ob unter praxisrelevanten Bedingungen die Entstehung von Wasserstoff an vollmartensitischen Schraubankern möglich ist. Im Gegensatz zu austenitischen Werkstoffen besteht bei martensitischen Werkstoffen bei Gegenwart von Wasserstoff stets die Möglichkeit einer wasserstoffinduzierten Versprödung des Materials. Hierfür wurde ein in der Praxis häufig anzutreffendes Szenario gewählt, das ein galvanisches Element, bestehend aus nichtrostenden Schraubankern (in diesem Fall martensitischen) und einer verzinkten Ankerplatte an einem Betonkörper, umfasst. Zum Nachweis einer Wasserstoffentwicklung werden der Elementstrom zwischen den Bauteilen sowie das Korrosionspotential erfasst. Die Ergebnisse der Versuche zeigen, dass über eine zeitlich begrenzte Dauer eine starke kathodische Polarisation der martensitischen Schraubanker durch die korrosive Auflösung des Zinks erfolgt. Als Folge kommt es zur Wasserzersetzung im Phasengrenzbereich der Schraubanker und zur Entstehung von atomarem Wasserstoff. Das berechnete Gasvolumen des entstandenen Wasserstoffs an den Stahlankern wurde bestimmt und lag im Mittel bei 11,14 ± 1,94 ml. Eine Diffusion des an der Stahloberfläche adsorbierten Wasserstoffs in den martensitischen Werkstoff ist somit theoretisch möglich und impliziert eine mögliche Gefährdung durch wasserstoffinduzierte Rissbildung und spontanes Versagen unter Belastung. N2 - The present investigation deals with the question of whether the formation of hydrogen is possible on fully martensitic screw anchors under practical conditions. In contrast to austenitic materials, martensitic steels always have the possibility of hydrogen-induced embrittlement of the material in the presence of hydrogen. For this purpose, a scenario was chosen which is frequently encountered in practice and which comprises a galvanic element consisting of stainless screw anchors (in this case martensitic) and a galvanized anchor plate on a concrete body. The element current between the components as well as the corrosion potential are recorded to prove hydrogen development. The results of the tests show that a strong cathodic polarization of the martensitic screw anchors occurs over a limited period due to the corrosive dissolution of the zinc. As a result, water decomposition occurs in the phase boundary area of the screw anchors and atomic hydrogen is formed. The calculated gas volume of the resulting hydrogen at the steel anchors was determined and was 11.14 +/- 1.94 ml on average. Diffusion of the hydrogen adsorbed on the steel surface into the martensitic material is thus theoretically possible and implies a possible risk of hydrogen-induced crack formation and spontaneous failure under load. KW - Martensit KW - Wasserstoff KW - Versprödung KW - Beton KW - Korrosion PY - 2020 DO - https://doi.org/10.1002/bate.202000017 SN - 0932-8351 SN - 1437-0999 VL - 97 SP - 1 EP - 7 PB - Wiley CY - Weinheim AN - OPUS4-50799 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Burkert, Andreas T1 - Bedingungen für den schadensfreien Einsatz von nichtrostenden Stählen N2 - Unter Passivität versteht man den Korrosionsschutz durch dünne, festhaftende Schichten aus Korrosionsprodukten. Für den schadensfreien Einsatz nichtrostender Stähle ergeben sich daraus zwei grundsätzliche Anforderungen. Erstens muss sich die Passivschicht vollständig ausbilden können. Dabei sind die Oberflächenausführung, die mechanische Bearbeitung, die Elementverteilung, Ausscheidungen, die Wärmeeinbringung z.B. bei der schweißtechnischen Verarbeitung, Anlauffarben, sowie die chemische Nachbehandlung bzw. Konditionierung der Oberflächen von großer Bedeutung. Zweitens muss die Repassivierung von Defektstellen unter den Einsatzbedingungen möglich sein. Für das Repassivierungsvermögen sind die Legierungszusammensetzung, mögliche kritische Betriebszustände, prozessbedingte Besonderheiten, wie etwa Stagnationsbedingungen und Reinigungsprozesse von Bedeutung. T2 - Nichtrostende Stähle - Eigenschaften und Anwendungen CY - Dusseldorf, Germany DA - 27.05.2025 KW - Passivität KW - Korrosion KW - Dauerhaftigkeit KW - Schadensursachen PY - 2025 AN - OPUS4-63242 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Müller, Thoralf T1 - Abschlussbericht zum FGS Vorhaben "Gefügeveränderungen bei trockener Grobbearbeitung" N2 - Der Vortrag stellt die Ergebnisse des Forschungsvorhabens zum Thema Gefügeveränderungen bei trockener Grobbearbeitung vor. Ziel des Vorhabens war die Identifizierung und Quantifizierung möglicher mechanisch- oder thermomechanisch-bedingter Gefügeveränderungen nach trockener Oberflächenbearbeitung. Es wurden opfische und metallografische Untersuchungen sowie Härtemessungen und elektrochemische Korrosionsuntersuchungen durchgeführt. T2 - Jahrestagung der Foschungsgemeinschaft Schleiftechnik e.V CY - Würzburg, Germany DA - 26.03.2025 KW - Stahl KW - Trockene Schleifbearbeitung KW - Metallografie KW - Mikrohärte KW - Korrosion PY - 2025 AN - OPUS4-62796 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Szymoniak, Paulina A1 - Kolmangadi, Mohamed A. A1 - Böhning, Martin A1 - Frick, B. A1 - Apple, M. A1 - Mole, R. A. A1 - De Souza, N. R. A1 - Zorn, R. A1 - Schönhals, Andreas T1 - Confined Segmental Diffusion in Nanophase Separated Janus Polynorbornenes as Investigated by Quasielastic Neutron Scattering N2 - A combination of neutron time-of-flight and neutron backscattering spectroscopy was used to investigate the molecular dynamics of Janus polynorbornenes (Janus poly(tricyclononenes)) on a microscopic level. These Janus polynorbornenes, denoted as PTCNSiOR, have a semirigid backbone with −Si(OR)3 side groups attached to it. R represents the length of the alkyl side chain. Here side chain lengths of R = 3 (propyl) and R = 8 (octyl) were considered. It is worth mentioning that these polymers have some potential as active layers in gas separation membranes, especially for the separation of higher hydrocarbons. The combination of time-of-flight and backscattering will ensure a reasonably broad time window for analysis where the incoherent intermediate scattering function SInc(q,t) is considered. Previously, it was shown by X-ray investigations that the system undergoes a nanophase separation into alkyl side chain-rich domains surrounded by a backbone-rich matrix. For PTCNSiOPr (R = 3), the alkyl side-chain-rich domains are truly isolated in the backbone-rich matrix, whereas for PTCNSiOOc (R = 8) these domains percolate through the matrix. Further, it was also previously shown that the alkyl side-chain-rich domains undergo a glass transition. The advantage of neutron scattering experiments discussed here is that besides temporal also spatial information is obtained which will allow conclusions to be drawn about the type of molecular fluctuations. At the lowest measured temperature, the decay in Sinc(q,t) is due to the methyl group rotation. The methyl group dynamics is analyzed in terms of a modified jump-diffusion in a 3-fold potential and yields to a reasonable fraction of hydrogens which contribute to the methyl group rotation. At higher temperatures, the decay in SInc(q,t) is due to both the methyl group rotation and the segmental dynamics in the alkyl side-chain-rich domains. The segmental diffusion is modeled by a sublinear diffusion. For the analysis of the scattering function SInc(q,t) of PTCNSiOPr an elastic scattering due to the immobilized backbone-rich matrix must be taken into account. The analysis reveals that the segmental dynamics is confined by the finite size of alkyl chain-rich domains and that it is intrinsically heterogeneous in nature. Both effects are more pronounced for PTCNSiOPr in comparison to those of PTCNSiOOc. KW - Polynorbornene KW - Quasielastic Neutron Scattering PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-608712 DO - https://doi.org/10.1021/acs.macromol.4c01045 SP - 1 EP - 14 PB - ACS Publications AN - OPUS4-60871 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schilling, Markus A1 - Marschall, Niklas A1 - Niebergall, Ute A1 - Wachtendorf, Volker A1 - Böhning, Martin T1 - Characteristics of environmental stress cracking of PE-HD induced by biodiesel and diesel fuels N2 - In the context of the increasing effect of carbon dioxide emissions on the global climate biodiesel produced from renewable sources has emerged as a promising contender replacing fossil fuels, especially in long-range transport vehicles, using existing engines and infrastructure. High-density polyethylene is one of the prevailing materials for pipe and container applications for storage and transport of such fuels, both, from fossil and renewable resources. The contact with the respective fuels raises questions concerning material compatibility as biodiesel exhibits significant differences compared to conventional diesel fuel affecting its sorption and plasticization behavior in polyethylene. In this study, its behavior with respect to environmental stress cracking, considered one of the most frequent damage mechanisms leading to failure of polymer parts and packaging, was evaluated using the well-established Full Notch Creep Test. This approach allows for a detailed fracture surface analysis using imaging techniques, such as optical and laser scanning microscopy, as well as infrared spectroscopy. Comparing the environmental stress cracking behavior in standard surfactant solutions with that in biodiesel and diesel, respective crack propagation rates, showing different levels of acceleration, were determined and details of the underlying mechanisms could be revealed. Furthermore, the specific infrared absorption of the biodiesel’s ester functionality allows its semi-quantitative determination on the fracture surface of the tested specimens after failure. Thus, a preferred uptake of sorptive fluids in the fracture zone due to local morphological changes of the polyethylene could be directly evidenced by infrared spectroscopy. KW - Environmental stress cracking (ESC) KW - Full notch creep test (FNCT) KW - Confocal laser scanning microscopy (LSM) KW - Biodiesel KW - Diesel PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-608591 DO - https://doi.org/10.1016/j.polymertesting.2024.108547 SN - 0142-9418 VL - 138 SP - 1 EP - 16 PB - Elsevier Ltd. AN - OPUS4-60859 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Szymoniak, Paulina A1 - Kolmangadi, Mohamed A. A1 - Böhning, Martin A1 - De Souza, N. R. A1 - Juranyi, F. A1 - Zorn, R. A1 - Schönhals, Andreas T1 - Inelastic and Quasielastic Neutron Scattering on Polynorbornenes with Bulky Carbocyclic Side groups N2 - This study investigates the molecular mobility and vibrational properties of polynorbornenes with bulky carbocyclic side groups using inelastic and quasielastic neutron scattering techniques. The polymers, synthesized via metathesis and addition polymerization, exhibit varying degrees of microporosity, which ignificantly influences their gas separation performance. By inelastic neutron scattering experiments, it could be shown that all considered polymers have excess contributions to the low frequency vibrational density of states known as the Boson peak. The maximum frequency of the Boson peak correlates to the microporosity of the polymers. This correlation supports the sound wave interpretation of the Boson peak, suggesting that the microporous structure enhances the compressibility of the material at a microscopic length scale. The molecular mobility, particularly the methyl group rotation, was characterized using elastic scans and quasielastic neutron scattering. The study revealed a temperature dependent relaxation process, with the onset of molecular fluctuations observed around 200 K for the polymer containing methyl groups. For the polymer having no methyl groups only elastic scattering is observed. The methyl group rotation was analyzed in terms of a jump diffusion in a threefold potential with three equivalent energy minima. This leads to an almost correct description of the q dependence of the elastic incoherent scattering function when the number of hydrogen nuclei undergoing the methyl group rotation is considered. It was further evidenced that the fraction of methyl undergoing the methyl group rotation increases with increasing temperature. KW - Polymers of Intrinsic Microporosity KW - Neutron scattering PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-630297 DO - https://doi.org/10.1016/j.polymer.2025.128358 SN - 1873-2291 VL - 328 SP - 241 PB - Elsevier Ltd. AN - OPUS4-63029 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Zorn, R. A1 - Szymoniak, Paulina A1 - Kolmangadi, Mohamed Aejaz A1 - Malpass-Evans, R. A1 - McKeown, N. A1 - Jalarvo, N. A1 - Tyagi, M. A1 - Böhning, Martin A1 - Schönhals, Andreas T1 - Microscopic molecular mobility of high-performance polymers of intrinsic microporosity revealed by neutron scattering – bend fluctuations and signature of methyl group rotation N2 - Polymers of intrinsic microporosity exhibit a combination of high gas permeability and reasonable permselectivity, which makes them attractive candidates for gas separation membrane materials. The diffusional selective gas transport properties are connected to the molecular mobility of these polymers in the condensed state. Incoherent quasielastic neutron scattering was carried out on two polymers of intrinsic microporosity, PIM-EA-TB(CH3) and its demethylated counterpart PIM-EA-TB(H2), which have high Brunauer–Emmett–Teller surface area values of 1030 m2 g-1 and 836 m2 g-1, respectively. As these two polymers only differ in the presence of two methyl groups at the ethanoanthracene unit, the effect of methyl group rotation can be investigated solely. To cover a broad dynamic range, neutron time-of-flight was combined with neutron backscattering. The demethylated PIM-EA-TB(H2) exhibits a relaxation process with a weak intensity at short times. As the backbone is rigid and stiff this process was assigned to bendand-flex fluctuations. This process was also observed for the PIM-EA-TB(CH3). A further relaxation process is found for PIM-EA-TB(CH3), which is the methyl group rotation. It was analyzed by a jump-diffusion in a three-fold potential considering also the fact that only a fraction of the present hydrogens in PIM-EATB(CH3) participate in the methyl group rotation. This analysis can quantitatively describe the q dependence of the elastic incoherent structure factor. Furthermore, a relaxation time for the methyl group rotation can be extracted. A high activation energy of 35 kJ mol-1 was deduced. This high activation energy evidences a strong hindrance of the methyl group rotation in the bridged PIM-EA-TB(CH3) structure. KW - Polymers of Intrinsic Microporosity KW - Neutron Scattering PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-604114 DO - https://doi.org/10.1039/d4sm00520a SP - 1 EP - 11 PB - RSC AN - OPUS4-60411 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Thuy, Maximilian A1 - Pedragosa-Rincon, M. A1 - Niebergall, Ute A1 - Oehler, H. A1 - Alig, I. A1 - Böhning, Martin T1 - Environmental Stress Cracking of High-Density Polyethylene Applying Linear Elastic Fracture Mechanics N2 - The crack propagation rate of environmental stress cracking was studied on high-density polyethylene compact tension specimens under static loading. Selected environmental liquids are distilled water, 2 wt% aqueous Arkopal N100 solution, and two model liquid mixtures, one based on solvents and one on detergents, representing stress cracking test liquids for commercial crop protection products. The different surface tensions and solubilities, which affect the energetic facilitation of void nucleation and craze development, are studied. Crack growth in surface-active media is strongly accelerated as the solvents induce plasticization, followed by strong blunting significantly retarding both crack initiation and crack propagation. The crack propagation rate for static load as a function of the stress intensity factor within all environments is found to follow the Paris–Erdogan law. Scanning electron micrographs of the fracture surface highlight more pronounced structures with both extensive degrees of plasticization and reduced crack propagation rate, addressing the distinct creep behavior of fibrils. Additionally, the limitations of linear elastic fracture mechanisms for visco-elastic polymers exposed to environmental liquids are discussed. KW - Crack propagation KW - Environmental stress cracking KW - Fracture toughness KW - Crop protection products KW - High-density polyethylene KW - Craze–crack mechanism KW - Linear elastic fracture mechanics KW - Stress intensity factor PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-550476 DO - https://doi.org/10.3390/polym14122415 SN - 2073-4360 VL - 14 IS - 12 SP - 1 EP - 21 PB - MDPI CY - Basel AN - OPUS4-55047 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Erdmann, Maren A1 - Kleinbub, Sherin A1 - Wachtendorf, Volker A1 - Schütter, Jan David A1 - Niebergall, Ute A1 - Böhning, Martin A1 - Koerdt, Andrea T1 - Photo-oxidation of PE-HD affecting polymer/fuel interaction and bacterial attachment N2 - In the present study, a simple approach was used to investigate the effect of UV-exposure on two high density Polyethylene materials (PE-HD), commonly used for storage tanks, on fuel sorption behavior and colonization by microorganisms. The aim was to investigate whether the sorption behavior of the fuels (diesel/biodiesel) and the colonization by microorganisms, frequently occurring in the fuel, is affected and may lead to undesirable or safety-relevant material changes. We showed that the UV-irradiation leads to significant changes of the sorption behavior due to chemi-crystallization and crosslinking. The fuel Sorption is affected by the UV-induced formation of polar carbonyl and hydroxyl groups predominantly occurring at the surface. With respect to microbial colonization behavior for Bacillus subtilis and Pseudomonas aeruginosa, isolated from a contaminated diesel sample, differences of the initial adhesion could be shown depending on the initial type of polyethylene as well as on the degree of UV-induced degradation. KW - High density polyethylene KW - Bacterial attachment KW - UV-irradiation KW - Fuel sorption PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-510001 DO - https://doi.org/10.1038/s41529-020-0122-1 VL - 4 IS - 1 SP - Article number: 18 PB - Nature Partner Journals AN - OPUS4-51000 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Zorn, R. A1 - Szymoniak, Paulina A1 - Kolmangadi, Mohamed Aejaz A1 - Malpass-Evans, R. A1 - McKeown, N. A1 - Tyagi, M. A1 - Böhning, Martin A1 - Schönhals, Andreas T1 - Low frequency vibrations and diffusion in disordered polymers bearing an intrinsic microporosity as revealed by neutron scattering N2 - The microscopic diffusion and the low frequency density of states (VDOS) of PIM-EATB(CH3) are investigated by inelastic and quasi-elastic neutron scattering where also the demethylated counterpart of PIM-EA-TB(H2) is considered. These intrinsic microporous polymers are characterized by large BET surface area values of several hundred m2/g and pore sizes between 0.5 and 2 nm. Detailed comparison is made to the archetype of polymers of intrinsic microporosity, PIM-1, and polynorbornenes also bearing a microporosity. Due to the wavelength of neutrons, the diffusion and vibrations can be addressed on microscopic length and time scales. From the inelastic neutron scattering experiments the low frequency density of states (VDOS) is estimated which shows excess contributions to the Debye-type VDOS known as Boson peak. It was found that the maximum frequency of the Boson peak decreases with increasing microporosity characterized by the BET surface area. However, besides the BET surface area, additional factors such as the backbone stiffness govern the maximum frequency of the Boson peak. Further the mean squared displacement related to microscopic motions was estimated from elastic fixed window scans. At temperatures above 175 K, the mean squared displacement PIM-EA-TB(CH3) is higher than that for the demethylated counterpart PIM-EA-TB(H2). The additional contribution found for PIM-EATB(CH3) is ascribed to the rotation of the methyl group in this polymer because the only difference between the two structures is that PIM-EA-TB(CH3) has methyl groups where PIM-EA-TB(H2) has none. A detailed comparison of the molecular dynamics is also made to that of PIM-1 and the microporous polynorbornene PTCNSi1. The manuscript focuses on the importance of vibrations and the localized molecular mobility characterized by the microscopic diffusion on the gas Transport in polymeric separation membranes. In the frame of the random gate model localized fluctuations can open or close bottlenecks between pores to enable the diffusion of gas molecules. KW - Polymer of intrisic microporosity KW - Neutron scattering KW - Boson peak KW - Methyl group rotation PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-538490 DO - https://doi.org/10.3390/cryst11121482 VL - 11 IS - 12 SP - 1 EP - 16 PB - MDPI CY - Basel AN - OPUS4-53849 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Erdmann, Maren A1 - Niebergall, Ute A1 - Wachtendorf, Volker A1 - Böhning, Martin T1 - Evaluation of UV-induced embrittlement of PE-HD by Charpy impact test N2 - The impact fracture behavior of two common high-density polyethylene grades for container applications were intensively studied by the instrumented Charpy impact test after well-defined exposure to UV-irradiation. Individual stages of the impact event, such as crack initiation and crack propagation energy as well as maximum impact load, were investigated from the recorded load–deflection curves. UV-induced material property changes were further investigated by infrared spectroscopy, differential scanning calorimetry, and dynamic-mechanical analysis as well as density measurements. Based on the results of the Charpy impact test, three indicators were identified to describe the extend of photooxidation on high-density polyethylene: (a) a reduced Charpy impact strength—at least to half of its initial value for a distinctly brittle impact fracture, (b) a marked decrease in the crack propagation contribution to the impact strength, and (c) an increase of the brittle features of the fracture surface. KW - Degradation KW - Mechanical properties KW - Packaging KW - Polyolefins KW - Polyethylene PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-509130 DO - https://doi.org/10.1002/APP.49069 SN - 0021-8995 VL - 137 IS - 36 SP - 49069 PB - Wiley AN - OPUS4-50913 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schilling, Markus A1 - Niebergall, Ute A1 - Marschall, Niklas A1 - Alig, I. A1 - Böhning, Martin T1 - A phenomenological criterion for an optical assessment of PE-HD fracture surfaces obtained from FNCT N2 - The full-notch creep test (FNCT) is a common test method to evaluate the environmental stress cracking (ESC) behavior of high-density polyethylene (PE-HD), e.g. for container materials. The test procedure as specified in ISO 16770 provides a comparative measure of the resistance against ESC using the time to failure of PE-HD specimens under constant mechanical load in a well-defined liquid test environment. Since the craze-crack damage mechanism underlying the ESC phenomenon is associated with brittle failure, the occurrence of a predominantly brittle fracture surface is a prerequisite to consider an FNCT measurement as representative for ESC, i.e. a time to failure dominated by craze-crack propagation. The craze-crack propagation continuously reduces the effective residual cross-sectional area of the specimen during the test, which results in a corresponding increase of the effective mechanical stress. Thus, a transition to ductile shear deformation is inevitable at later stages of the test, leading usually to a pronounced central ligament. Therefore, an optical evaluation of FNCT fracture surfaces concerning their brittleness is essential. An enhanced imaging analysis of FNCT fracture surfaces enables a detailed assessment of craze-crack Propagation during ESC. In this study, laser scanning microscopy (LSM) was employed to evaluate whether FNCT fracture surfaces are representative with respect to craze-crack propagation and ESC. Based on LSM height data, a phenomenological criterion is proposed to assess the validity of distinct FNCT measurements. This criterion is supposed to facilitate a quick evaluation of FNCT results in practical routine testing. Its applicability is verified on a sample basis for seven different commercial PE-HD container materials. KW - Environmental stress cracking (ESC) KW - Full notch creep test (FNCT) KW - Laser scanning microscopy (LSM) KW - Fracture surfaces KW - Optical criterion of brittleness PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-521012 DO - https://doi.org/10.1016/j.polymertesting.2020.107002 VL - 94 SP - 107002 PB - Elsevier Ltd. CY - Amsterdam AN - OPUS4-52101 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CHAP A1 - Schönhals, Andreas A1 - Böhning, Martin A1 - Szymoniak, Paulina ED - Schönhals, Andreas ED - Szymoniak, Paulina T1 - (Nano)Composite Materials—An Introduction N2 - The chapter gives a brief introduction to (nano)compositecomposite materials having the focus on polymer-based nanocomposites. The different dimensionalities of nanoparticles are introduced, along with their distribution in the matrix. Different application fields of polymer-based nanocomposites, like flame retardancy, filled rubbers, nanofilled thermosets and thermoplastics, separation membranes and nanodielectrics, are considered in greater detail. KW - Polymer-based nanocomposites KW - Nanoparticle KW - Distribution of nanoparticles KW - Filled rubbers KW - Filled thermosets and plastics KW - Separation membranes KW - Nanodielectrics PY - 2022 DO - https://doi.org/10.1007/978-3-030-89723-9_1 SP - 1 EP - 31 PB - Springer CY - Cham, Switzerland AN - OPUS4-54565 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Emamverdi, Farnaz A1 - Yin, Huajie A1 - Smales, Glen Jacob A1 - Harrison, W. J. A1 - Budd, P. M. A1 - Böhning, Martin A1 - Schönhals, Andreas T1 - Polymers of intrinsic microporosity - Molecular mobility and physical aging revisited by dielectric spectroscopy and X‑ray scattering N2 - Polymers of intrinsic microporosity (PIMs) are promising candidates for the active layer in gas separation membranes due to their high permeability and reasonable permselectivity. These appealing properties originate from a microporous structure as a result of inefficient segment packing in the condensed state due to a combination of a ladder-like rigid backbone and sites of contortion. However, this class of polymers suffers from a significant decrease in the permeability with time due to physical aging, whereby typically, the permselectivity increases. The initial microporous structures approach a denser state via local rearrangements, leading to the reduction of the permeability. Hence, a detailed characterization of the molecular mobility in such materials can provide valuable information on physical aging. In this work, the dielectric behavior of PIM-1 films and their behavior upon heating (aging) were revisited by isothermal frequency scans during different heating/cooling cycles over a broad temperature range between 133 and 523 K (−140 to 250 °C). In addition, the obtained results were compared with data of samples that were annealed at ambient temperatures over different time scales. Multiple dielectric processes were observed: several relaxation processes due to local fluctuations and a Maxwell−Wagner−Sillars polarization effect related to the microporosity. The temperature dependence of the rates of all processes follows the Arrhenius law where the estimated activation energy depends on the nature of the process. The influence of the thermal history (aging) on the processes is discussed in detail. KW - Polymers of intrinsic microporosity PY - 2022 DO - https://doi.org/10.1021/acs.macromol.2c00934 VL - 55 SP - 7340 EP - 7350 PB - American Chemical Society CY - Washington, DC AN - OPUS4-55485 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Szymoniak, Paulina A1 - Kolmangadi, Mohamed A. A1 - Juranyi, Fanni A1 - Böhning, Martin A1 - Zorn, Reiner A1 - Schönhals, Andreas T1 - Low-Frequency Vibrational Density of State of Janus-Polynorbornenes: The Dependence of the Boson Peak on the Nanophase-Separated Structure N2 - Inelastic incoherent neutron time-of-flight scattering was employed to investigate the low-frequency vibrational density of states (VDOSs) for a series of glassy Janus-poly(tricyclononenes), which consist of a rigid main chain and flexible alkyl side chains. Here, the length of the flexible side chains was systematically varied from propyl to octyl. Such materials have potential applications as active separation layers in gas separation membranes as a green future technology, especially for the separation of higher hydrocarbons. From the morphological point of view, the Janus polynorbornenes undergo a nanophase separation into alkyl side chain-rich nanodomains surrounded by a rigid polynorbornene matrix. Here, the influence of the nanophase-separated structure on the low-frequency VDOS is investigated from a fundamental point of view. The low-frequency VDOSs of these Janus polynorbornene show excess contributions to the Debye type VDOS known as the Boson peak (BP) for all side chain lengths. Due to the high incoherent scattering cross-section of hydrogen, most of the scattering comes from the alkyl side chain-rich domains. Compared to conventional glass-forming materials, in the considered Janus polynorbornenes, the BP has a much lower intensity and its frequency position is shifted to higher values. These experimental results are discussed in terms of the nanophase-separated structure where the alkyl chain-rich domains were constrained by the surrounding matrix dominated by the rigid backbone. With increasing alkyl chain length, the size of the alkyl chain-rich domains increases. The frequency position of the BP shifts linearly to lower frequencies with the size of these nanodomains estimated from X-ray measurements. The obtained results support the sound wave interpretation to the BP KW - Inelastic neutron scattering PY - 2023 DO - https://doi.org/10.1021/acs.macromol.3c00913 SN - 0024-9297 SP - 1 EP - 10 PB - ACS AN - OPUS4-57972 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Szymoniak, Paulina A1 - Böhning, Martin A1 - Zorn, Reiner A1 - Schönhals, Andreas T1 - Inelastic and quasielastic neutron scattering experiments on microporous membranes fro green separation processes N2 - Polymers with intrinsic microporosity are promising candidates for the active separation layer in gas separation membranes. These polymers are characterized by a high permeability and reasonable permselectivity. The latter point is somehow surprising because for microporous systems a more Knudson-like diffusion is expected then a size dependent temperature activated sieving process. It was argued in the framework of a random gate model that molecular fluctuations on a time scale from ps to ns are responsible for the permselectivity. Here series of polymers of intrinsic microporosity (PIMs) as well as microporous polynorbornenes with bulky Si side groups and a rigid backbone are considered. The polymers have different microporosity characterized by high BET surface area values. First inelastic time-of-flight neutron scattering measurements were carried out to investigate the low frequency density of state (VDOS). The measured data show the characteristic low frequency excess contribution to the VDOS above the Debye sound wave level, generally known as the Boson peak in glass-forming materials. It was found that the frequency of the maximum position of the Boson peak correlates with the BET surface area value. Secondly elastic scans as well as quasielastic neutron scattering measurements by a combination of neutron time-of-flight and backscattering have been out. A low temperature relaxation process was found for both polymers. This process was assigned to the methyl group rotation. It was analysed in terms of a jump diffusion in a three-fold potential. The analysis of the dependence of the elastic incoherent structure factor on the scattering vector yields the number of methyl groups which might be immobilized. The neutron scattering experiments were accompanied by fast scanning calorimetry and broadband dielectric investigations as well as atomistic molecular dynamic simulations. T2 - Kolloquiumsvortrag an der Technischen Universität München CY - Garching, Germany DA - 20.11.2023 KW - Polymers with intrinsic microporosity PY - 2023 AN - OPUS4-59036 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Emamverdi, Farnaz T1 - Molecular Mobility and Physical Aging of Polymers with Intrinsic Microporosity (PIM-1) Revisited: A Big Glassy World N2 - Polymeric membranes represent a cost- and energy-efficient solution for gas separation. Recently Polymers of Intrinsic Microporosity (PIMs) have been in a great interest because of their outstanding BET surface area larger than 700m2/g and pore size smaller than 1 nm. PIMs are a promising candidate in gas separation with high permeability and appealing selectivity due to their inefficient packing derived from a combination of ladder-like rigid segments with sites of contortion. However, it is recognized this class of polymers suffer from decrease in performance with time due to physical aging. The initial microporous structures approach a denser state via local chain rearrangements, leading to a dramatic reduction in permeability. As chain packing during film casting and physical aging are the key factors determine the performance in separation applications, characterization of the molecular mobility in these materials has been proved to provide valuable information. In recent research on PIM-1 the archetypal PIM, a molecular relaxation process with high activation energy together with a significant conductivity in the glassy state has been found and explained with the formation of local intermolecular agglomerates due to interaction of π-electrons in aromatic moieties of the polymer backbone. In this work, the dielectric behavior of the polymeric films and their response upon heating (aging) were measured by isothermal frequency scans during different heating/cooling cycles in a broad temperature range down to 133K for the first time. Multiple dielectric processes following Arrhenius behavior were observed. Local fluctuations, Maxwell-Wagner-Sillars (MWS) polarization and structural relaxations were discussed correlating to structural-properties of PIM-1. Up to now, no other work has studied the role of porosity and thermal history of PIM-1 film in dielectric processes. The goal is by eliminating thermal history and considering storing conditions provide better understanding on aging and plasticizing in high free volume glassy polymer PIM-1. T2 - IDS Online Meeting CY - Berlin, Germany DA - 06.09.2021 KW - Physical Aging KW - BDS KW - Microporous structure KW - Permeation PY - 2021 AN - OPUS4-55766 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Emamverdi, Farnaz T1 - Molecular mobility and gas transport properties of mixed matrix membranes based on PIM-1 and POF fillers N2 - Especially now in times of the energy revolution, the demand for energy-efficient separation processes promotes the advancement of new high-performance materials for use as highly selective separation membranes. Polymers with intrinsic microporosity (PIMs) are of high interest in the field of gas separation membranes. Currently the application of PIMs for membrane technology is still restrained by their strong tendency to physical aging involving a significant loss of their good gas separation properties. Physical aging phenomenon is related to the molecular mobility of PIMs which was investigated by broadband dielectric spectroscopy (BDS) previously [1]. In this work, covalent phosphinine-based framework (Eto-CPSF) was used as a nanofiller (0-10 wt %) in a PIM-1 matrix to potentially enhance the gas transport properties and prevent physical aging. Since molecular mobility is a fundamental parameter determining gas transport as well as physical aging in such a material, our study includes dielectric investigations by BDS of pure PIM-1 and PIM-1/Eto-CPSF mixed matrix membranes to establish a correlation between molecular mobility and gas transport properties. In addition, gas permeability was determined by the time-lag method (0-10 bar pressure) at 35 °C for N2, O2, CH4 and CO2 for all MMMs. The dielectric behavior of the polymeric films and their response upon heating were measured by isothermal frequency scans during different heating/cooling cycles in a broad temperature range up to 250 °C. Multiple dielectric processes following Arrhenius behavior were observed. Local fluctuations, Maxwell-Wagner-Sillars (MWS) polarization and structural relaxations were discussed correlating to structural-properties of PIM-1. As main result for MMMs, the permeability of PIM-1 for CH4 and CO2 gases were increased significantly with only 5 wt% of nanofiller within the polymer matrix. However, this is not observed for Eto-CPSF concentrations higher than ca. 7 wt% probably due to a microphase separated morphology of the nanocomposite system. Furthermore, the permselectivity of membranes for pair gases O2/N2 and CO2/N2 show enhancement up to a concentration of about 7 wt% Eto-CPSF filler. T2 - 11th BDS conference CY - San Sebastian, Spain DA - 04.09.2022 KW - Gas transport KW - BDS KW - Mixed Matrix Membrane KW - Nanocomposite PY - 2022 AN - OPUS4-55752 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kupsch, Andreas T1 - Warum wird zugbelastetes HD-Polyethylen in Dieselumgebung transparent? – Antworten der Röntgenstreuung N2 - Behälter aus hochdichtem Polyethylen (PE-HD) werden zur Lagerung und für den Transport von Kraftstoffen eingesetzt. Beim Kontakt beider Medien diffundiert der Kraftstoff in das Polymer, erhöht dessen Volumen und Duktilität und ändert damit das Fließverhalten des Polymers unter Zugbelastung. Zudem weist PE-HD in Luft im verstreckten Bereich das sogenannte strain-whitening (Lichtstreuung) auf, während in Diesel gelagertes PE-HD optisch transparent wird. Zur Untersuchung dieses Phänomens wurden ortsaufgelöste Röntgenrefraktion und –diffraktion (Topographie) eingesetzt. Aus Sicht der molekularen Struktur (Diffraktion) weisen die beiden Probentypen keine Unterschiede auf: im verstreckten Bereich liegt eine „Fasertextur“ der Polymerketten in Belastungsrichtung vor, im unverstreckten Bereich nahezu ideale Isotropie. Die für mikroskopische Strukturen empfindliche Röntgenrefraktion zeigt außerdem für die Probe in Luft im verstreckten Bereich eine ausgeprägte Orientierung von Grenzflächen in Zugrichtung, während die in Diesel gelagerte Probe keine Grenzflächen zeigt. In Analogie zum optischen Verhalten bewirken die ähnlichen Brechungsindizes beider Medien im Röntgenbereich, dass eindiffundierter Diesel als Immersionsflüssigkeit die Brechungseigenschaften herabsetzt. T2 - DACH-Jahrestagung 2019 CY - Friedrichshafen, Germany DA - 27.05.2019 KW - Diesel KW - HDPE Soprption KW - Kavitation KW - Mikrostruktur KW - Röntgenbeugung KW - Röntgenrefraktion PY - 2019 AN - OPUS4-48334 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Thuy, Maximilian A1 - Brauch, N. A1 - Niebergall, Ute A1 - Alig, I. A1 - Oehler, H. A1 - Böhning, Martin T1 - Environmental Stress Cracking of PE-HD Induced by Liquid Test Media Representing Crop Protection Formulations N2 - Packaging containers for dangerous goods that include aggressive liquids require that any packaging material that is based on high-density polyethylene has a high degree of stability and durability. This work is focused on testing the environmental stress cracking of the high-density polyethylenes used for such containers in contact with crop protection formulations, in particular, two model liquids established in Germany as standardized test media representatives for crop protection formulations containing the various admixtures typical for such products. One of the liquids is water-based and contains mostly surface-active ingredients, while the other is solvent-based and includes some emulsifiers. Originally established for pin impression tests, these model liquids and their individual components were here used for the first time as environmental media in the Full Notch Creep Test, which addresses the resistance against environmental stress cracking. The Full Notch Creep Test was carried out on five high-density polyethylene types with both model liquids, and also on one selected material with its components. The evaluation was focused on the fracture surface structures, which were visualized by a scanning electron microscope and by optical in situ imaging of the notch opening. While the water-based model liquid and its surface-active individual components induced environmental stress cracking with the characteristic pattern for a craze-crack mechanism and so-called brittle fracture on the surface, the solvent-based model liquid and its soluble ingredients exhibited rather ductile failure behavior, caused by the plasticizing effect on the polymer that reduced the yield stress of the high-density polyethylene. For both cases, fracture surface analysis, together with side views of the crack opening, showed a clear relation between surface pattern, notch deformation (e.g., by blunting), or crack opening due to crack growth with time to failure and the solubility of the liquids in high-density polyethylene. KW - Environmental stress cracking KW - Fracture surface KW - Full Notch Creep Test KW - Crop protection formulations KW - High-density polyethylene PY - 2023 DO - https://doi.org/10.1520/STP164320210095 SP - 317 EP - 341 PB - ASTM International CY - West Conshohocken, PA (USA) AN - OPUS4-57459 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CHAP A1 - Böhning, Martin A1 - Frasca, Daniele A1 - Schulze, Dietmar A1 - Schartel, Bernhard ED - Yaragalla, S. ED - Kumar Mishra, R. ED - Thomas, S. ED - Kalarikkal, N. ED - Maria, H. J. T1 - Multilayer Graphene/Elastomer Nanocomposites N2 - Elastomers are usually reinforced by large amount of fillers like carbon black (CB) or silica in order to improve various mechanical properties, such as Young’s modulus, hardness, tear resistance, abrasion resistance, and gas barrier properties. In recent years, such improvements were also obtained by using nanoparticles at significantly lower filler loadings. Graphene is a twodimensional (2D) sheet of a thickness in the atomic scale, composed of a honeycomb structure of sp2 carbon atoms. Besides significant mechanical reinforcement, graphene harbors the potential to be used as a multifunctional filler, as it can also increase the conductivity and weathering stability of elastomer matrices. Ultraviolet (UV) irradiation and oxidative agents can lead to the degradation of elastomers due to a multistep photooxidative process, including the formation of radicals. Carbon-based fillers have an influence on these reactions, as they can absorb UV radiation and act as radical scavengers. This chapter summarizes the results of our larger project on multilayer graphene (MLG)/elastomer nanocomposites, previously published, which present a comprehensive case study of MLG as a multifunctional nanofiller in elastomer/graphene nanocomposites. Different elastomeric matrices are compared in order to demonstrate the outstanding impact of MLG as a general benefit. The dependency of this effect on concentration is discussed in detail. Taking into account the key role of dispersion, different mixing procedures are compared, evaluating a facile implementation of graphene nanocomposites into conventional rubber processing. Finally, the most probable commercial uses of MLG nanofillers in combination with conventional CB are studied. The nanocomposites were prepared in the kg scale in order to obtain enough specimens to investigate various properties of the uncured and vulcanized rubbers at the highest quality level, including rheology, curing, morphology, several mechanical properties, abrasion, conductivity, gas permeation, burning behavior, and weathering stability. The structure property relationships are asserted and questioned, for example, by investigating the radical scavenging ability or aspect ratio of the MLG. This chapter illustrates the state of the art of graphene/rubber nanocomposites targeted for commercial mass applications. KW - Nanocomposite KW - Graphene KW - Rubber KW - Reinforcement KW - Durability KW - Masterbatch KW - Gas Barrier Properties KW - Conductivity PY - 2019 SN - 978-0-12-817342-8 SP - 139 EP - 200 PB - Elsevier AN - OPUS4-47408 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Erdmann, Maren A1 - Böhning, Martin A1 - Niebergall, Ute T1 - Physical and chemical effects of biodiesel storage on high-density polyethylene: Evidence of co-oxidation N2 - The physical and chemical effects of diesel and biodiesel fuels on two high-density polyethylene (PE-HD) types were investigated. Both semi-crystalline PE-HD are common thermoplastic materials for container and storage tank applications. Biodiesel, a composition of unsaturated fatty acid esters from renewable resources, was chosen as it is regarded a possible green alternative to fossil fuels. The study aims at identifying significant differences between biodiesel and conventional diesel fuels based on the differences in the chemical nature of the two. The physical effects of the fuels on the polymer at first comprises the sorption behavior, i.e. kinetics and final equilibrium concentration. Not only are both fuels absorbed by the amorphous phase of the semi-crystalline PE-HD, they also induce a plasticization effect that modifies the molecular mobility and therefore also the characteristic yielding properties, manifest in the obtained stress-strain curves. The chemical effects related to degradation phenomena is investigated by a long-term storage scenario using partially immersed tensile test specimens in diesel and biodiesel. We were able to confirm the proposed co-oxidation mechanism by Richaud et al. for polyethylene-unsaturated penetrant systems on a larger scale based on practical tensile tests. One of the investigated polyethylene grades subjected to tensile drawing showed a significant loss of plastic deformation and the onset of premature failure after 150 days of storage in biodiesel. Further biodiesel storage showed a systematically reduced elongation at break before necking. None of these effects were observed in diesel. Oxidation of fuels and polymer after progressing storage times were analyzed by the evolution of carbonyl species in FT-IR/ATR spectroscopy. KW - Biodiesel KW - Degradation KW - Long-term storage KW - Sorption KW - Diesel PY - 2019 DO - https://doi.org/10.1016/j.polymdegradstab.2019.01.018 SN - 0141-3910 VL - 161 IS - 1 SP - 139 EP - 149 PB - Elsevier CY - Amsterdam AN - OPUS4-47268 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Yin, Huajie T1 - Molecular Mobility and Charge Transport in Polymers of Intrinsic Microporosity (PIMs) as Revealed by Dielectric Spectroscopy N2 - Polymeric membranes represent a low-cost, energy efficient solution for gas separation. Recently polymers of intrinsic microporosity (PIMs) have emerged as prestigious membrane materials featuring a large concentration of pores smaller than 1 nm, a BET surface area larger than 700 m2/g and high gas permeability and selectivity. Unusual chain structure combining rigid segments with sites of contortion gives rise to the intrinsic microporosity. However, this novel class of glassy polymers are prone to pronounced physical aging. The initial microporous structures approach a denser state via local small scale fluctuataions, leading to a dramatic reduction in the gas permeabilities. For the first time, dielectric relaxation spectroscopy with state-of-the-art high-resolution analyzers was employed to investigate three representative PIMs with a systematic change in chain rigidity: PIM-EA-TB 〉 PIM-1 〉 PIM-MDPH-TB. The molecular mobility, the charge transport and their response upon heating (aging) in the polymers were measured in a broad temperature range through isothermal frequency scans during different heating / cooling cycles. Multiple dielectric processes following Arrhenius behavior were observed for the investigated polymers. Local fluctuations, Maxwell-Wagner-Sillars (MWS) polarization and structural relaxation phenomena were discussed and attempted to be correlated with the structural features of PIMs. Moreover, all PIMs showed conductivity in the glassy state. The significant increase in the conductivity with increasing temperature far below the glass transition temperature of PIMs is explained in terms of the loosely packed microporous structure and the formation of local intermolecular agglomerates due to interaction of π-electrons in aromatic moieties of the polymer backbone. T2 - American Chemical Society (ACS) National Meeting & Expo 2019 CY - Orlando, FL, USA DA - 31.03.2019 KW - Dielectric spectroscopy KW - Polymeric membrane KW - Polymers of intrinsic microporosity PY - 2019 AN - OPUS4-47805 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Strommer, Bettina T1 - Networking Skills: The Effect of Graphene on Crosslinking N2 - 2D layered nanoparticles enable a distinct reduction of filler loadings in rubber compounds combined with a boost in performance due to their high surface to volume ratio. They often enable unique property profiles providing a great potential as effective fillers in rubber, especially by enhancing mechanical and barrier properties. As the best possible incorporation into the elastomer matrix is crucial for the efficiency of the nanofiller, dispersing and exfoliation of the nanoparticles without formation of agglomerates usually constitutes an outstanding challenge - especially when using conventional processing methods. Laboratory-scale approaches for highly dispersed nanocomposites sometimes solve this problem, but these are often too energy and time consuming and provide no scale up possibility for real applications. Therefore, a latex premixing process was established to produce highly filled masterbatches, enabling the processing with conventional techniques. The presence of nanoparticles greatly impacts the behavior of elastomeric compounds, besides affecting the properties of the final product also the processing is influenced (rheology, crosslinking). In this study, nanocomposites of natural rubber and multilayer graphene (MLG) were prepared via a latex masterbatch route. Different strategies for masterbatch premixing are compared (stirring vs. ultrasonication, coagulation vs. drying). Dispersion and exfoliation of MLG were determined by transmission electron microscopy. The reinforcing effect of MLG affects the viscosity while the dispersed graphene layers may also act as diffusion barrier/absorbent for the crosslinking agents. In contrast to that, MLG forms physical crosslinks in the final product. Swelling measurements and differential scanning calorimetry allow a differentiation between chemical and physical network links. Different technical properties of the nanocomposites were measured with respect to mechanical and application relevant behavior. T2 - PPS 37 CY - Online meeting DA - 12.04.2022 KW - Elastomers KW - Nanocomposites KW - Graphene KW - Nanoparticles KW - Latex KW - Natural rubber KW - Processing PY - 2022 AN - OPUS4-54696 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Yin, Huajie A1 - Chapala, P. A1 - Bermeshev, M. A1 - Pauw, Brian Richard A1 - Schönhals, Andreas A1 - Böhning, Martin T1 - Influence of Trimethylsilyl Side Groups on the Molecular Mobility and Charge Transport in Highly Permeable Glassy Polynorbornenes N2 - Superglassy polymers with a large fractional free volume have emerged as novel materials with a broad range of applications, especially in the field of membrane separations. Highly permeable addition-type substituted polynorbornenes with high thermal resistance and chemical stability are among the most promising materials. The major obstacle for extending the practical membrane application is their strong tendency to physical aging, leading to a partial decline in their superior transport performance over time. In the present study, broadband dielectric spectroscopy with complementary X-ray scattering techniques were employed to reveal changes in microporous structure, molecular mobility, and conductivity by systematic comparison of two polynorbornenes with different numbers of trimethylsilyl side groups. Their response upon heating (aging) was compared in terms of structure, dynamics, and charge transport behavior. Furthermore, a detailed analysis of the observed Maxwell−Wagner−Sillars polarization at internal interfaces provides unique information about the microporous structure in the solid films. The knowledge obtained from the experiments will guide and unlock potential in synthesizing addition-type polynorbornenes with versatile properties. KW - Dielectric spectroscopy KW - Molecular mobility KW - Electrical conductivity KW - Gas separation membranes PY - 2019 DO - https://doi.org/10.1021/acsapm.9b00092 SN - 2637-6105 VL - 1 IS - 4 SP - 844 EP - 855 PB - ACS CY - Washington DC AN - OPUS4-47838 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Erdmann, Maren A1 - Kupsch, Andreas A1 - Müller, Bernd R. A1 - Hentschel, Manfred P. A1 - Niebergall, Ute A1 - Böhning, Martin A1 - Bruno, Giovanni ED - Erdmann, Maren T1 - Diesel-induced transparency of plastically deformed high-density polyethylene N2 - High-density polyethylene becomes optically transparent during tensile drawing when previously saturated with diesel fuel. This unusual phenomenon is investigated as it might allow conclusions with respect to the material behavior. Microscopy, differential scanning calorimetry, density measurements are applied together with two scanning X-ray scattering techniques: wide angle X-ray scattering (WAXS) and X-ray refraction, able to extract the spatially resolved crystal orientation and internal surface, respectively. The sorbed diesel softens the material and significantly alters the yielding characteristics. Although the crystallinity among stretched regions is similar, a virgin reference sample exhibits strain whitening during stretching, while the diesel-saturated sample becomes transparent. The WAXS results reveal a pronounced fiber texture in the tensile direction in the stretched region and an isotropic orientation in the unstretched region. This texture implies the formation of fibrils in the stretched region, while spherulites remain intact in the unstretched parts of the specimens. X-ray refraction reveals a preferred orientation of internal surfaces along the tensile direction in the stretched region of virgin samples, while the sample stretched in the diesel-saturated state shows no internal surfaces at all. Besides from stretching saturated samples, optical transparency is also obtained from sorbing samples in diesel after stretching. KW - PE-HD Sorption KW - Cavitation KW - Diesel Fuel KW - X-ray refraction KW - WAXS KW - Internal Surfaces KW - Crystal Texture PY - 2019 DO - https://doi.org/10.1007/s10853-019-03700-8 SN - 1573-4803 SN - 0022-2461 VL - 54 IS - 17 SP - 11739 EP - 11755 PB - Springer US CY - US AN - OPUS4-48226 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Böhning, Martin T1 - Characterization of high-performance membrane polymers for gas separation using broadband dielectric spectroscopy N2 - In recent years superglassy polymers exhibiting intrinsic microporosity established a new perspective for a number of applications, especially for gas separation membranes as These polymers Combine extremely high permeabilities with attractive selectivities. The essential factor governing the structure Formation in the solid film or layer is either a contorted rigid Backbone (polymers of intrinsic microporosity - PIMs) or extremely bulky side groups (polynorbornenes and polytricyclonenenes). For a deeper understanding of both types of such high-Performance polymers for gas separation membranes and their further development broadband dielectric spectroscopy (BDS) can provide a substantial contribution. BDS addresses molecular relaxations characterizing the dynamics of the solid polymer as a major factor determining the gas transport properties but also the physical aging behavior which is an essential issue for such polymers. BDS is applied on PIMs where fluctuations of molecular dipoles connected to the backbone can be directly monitored. Furthermore, also polynorbornenes were investigated which carry no dipole moment in their repeat unit - the high resolution of modern equipment allows for the detailed analysis also for very small dielectric losses originating from partially oxidized moieties or marginal catalyst residues. Additionally, from interfacial polarization phenomena, such as Maxwell-Wagner-Sillars (MWS) polarization due to blocking of charge carriers at internal interfacial boundaries on a mesoscopic length scale, valuable information on the intrinsic microporosity and its changes induced by physical aging can be obtained. Finally, also conductivity can be characterized in detail in such polymeric systems revealing contributions of interactions of aromatic moieties (π-π-stacking) or the drift motion of charge carriers. These features also determine the structure formation in the solid state. T2 - 257th ACS National Meeting - Symposium "Transport in Polymer Membranes" CY - Orlando, FL, USA DA - 31.03.2019 KW - polymers KW - gas separation membranes KW - polynorbornenes KW - polymers of intrinsic microporosity KW - dielectric spectroscopy KW - molecular mobility PY - 2019 AN - OPUS4-48142 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Yin, Huajie T1 - Probing the glass transition temperature of polymers of intrinsic microporosity (PIMs) by fast scanning calorimeter N2 - High performance polymers of intrinsic microporosity (PIMs) have emerged as novel materials with broad applications from gas separation to electronic devices. Sufficiently rigid, even contorted polymer chains show only limited molecular mobility, therefore undergo inefficient packing and give rise to intrinsic microporosity with pore size generally smaller than 1 nm and BET surface areas larger than 700 m2/g. Further performance optimization and long-term stability of devices incorporating PIMs rely on our understanding of structure-processing-property relationships and physical aging, in which glass transition plays a key role. Up to now no glass transition temperature (Tg) of PIMs could be detected with conventional thermal analysis techniques before degradation. Decoupling the time scales responsible for the glass transition and the thermal decomposition is a reliable strategy to overcome this. This was achieved by employing fast scanning calorimetry (FSC) based on a chip sensor, which is capable to heat and cool a small sample (ng-range) with ultrafast rates of several ten thousand K/s. FSC provides definitive evidence of glass transition of a series of PIMs with a special consideration on the chain rigidity. The determined glass transition temperature of these PIMs follows the order of the rigidity of their backbone structures. FSC provides the first clear-cut experimental evidence of the glass transition of PIM-EA-TB with a Tg of 663 K, PIM-1 of 644 K and PIM-DMDPH-TB of 630 K at a heating rate of 1Χ104 K/s. Local fluctuations are featured in glass transition of highly rigid PIMs. As conformational changes are prevented by the backbone rigidity, the glass transition must rather be assigned to local small scale fluctuations. T2 - American Chemical Society (ACS) National Meeting & Expo 2019 CY - Orlando, FL, USA DA - 31.03.2019 KW - Glass transition KW - Polymers of intrinsic microporosity KW - Fast scanning calorimeter PY - 2019 AN - OPUS4-47806 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kupsch, Andreas T1 - Warum wird zugbelastetes HD-Polyethylen in Dieselumgebung transparent? N2 - Behälter aus hochdichtem Polyethylen (PE-HD) werden zur Lagerung und für den Transport von Kraftstoffen eingesetzt. Beim Kontakt beider Medien diffundiert der Kraftstoff in das Polymer, erhöht dessen Volumen und Duktilität und ändert damit das Fließverhalten des Polymers unter Zugbelastung. Zudem weist PE-HD in Luft im verstreckten Bereich das sogenannte strain-whitening (Lichtstreuung) auf, während in Diesel gelagertes PE-HD optisch transparent wird. Zur Untersuchung dieses Phänomens wurden ortsaufgelöste Röntgenrefraktion und –diffraktion (Topographie) eingesetzt. Aus Sicht der molekularen Struktur (Diffraktion) weisen die beiden Probentypen keine Unterschiede auf: im verstreckten Bereich liegt eine „Fasertextur“ der Polymerketten in Belastungsrichtung vor, im unverstreckten Bereich nahezu ideale Isotropie. Die für mikroskopische Strukturen empfindliche Röntgenrefraktion zeigt außerdem für die Probe in Luft im verstreckten Bereich eine ausgeprägte Orientierung von Grenzflächen in Zugrichtung, während die in Diesel gelagerte Probe keine Grenzflächen zeigt. In Analogie zum optischen Verhalten bewirken die ähnlichen Brechungsindizes beider Medien im Röntgenbereich, dass eindiffundierter Diesel als Immersionsflüssigkeit die Brechungseigenschaften herabsetzt. T2 - DACH-Jahrestagung 2019 CY - Friedrichshafen, Germany DA - 27.05.2019 KW - Diesel KW - HDPE Sorption KW - Röntgenrefraktion KW - Röntgenbeugung KW - Mikrostruktur KW - Kavitation PY - 2019 AN - OPUS4-48311 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Maximilian, Thuy A1 - Spyrantis, Alexander A1 - Böhning, Martin A1 - Niebergall, Ute A1 - Maaß, Robert T1 - Spatially resolved roughness exponent in polymer fracture N2 - The fracture surface of slow and continuous crack propagation during environmental stress cracking of a semicrystalline polyethylene exhibits isotropic roughness exponents at the local scale but resolved across the macroscopic fracture surface a clear position dependence is found. The spatially resolved roughness exponent admits values in the range between 0.1 and 0.4, demonstrating nontrivial exponents in the small length-scale regime. Instead, they vary across the fracture surface according to the stress-state distribution, which suggests that the exponents are intimately linked to the locally dominating dissipation processes during craze cracking. KW - Plasticity KW - Fracture KW - Material failure KW - Mechanical deformation PY - 2022 DO - https://doi.org/10.1103/PhysRevMaterials.6.L090601 VL - 6 IS - 9 SP - 1 EP - 7 PB - American Physical Society CY - USA, Maryland AN - OPUS4-55797 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Thuy, Maximilian T1 - Umgebungsbedingter Spannungsriss: Gefahr für Kunststoffbauteile unter Medieneinfluss N2 - Polyethylen hoher Dichte (PE-HD) ist ein weit verbreitetes Material für Transportbehälter, die oft für eine längere Nutzungsdauer vorgesehen sind. Insbesondere in diesem Fall können mikroskopische Schäden im Material auch weit unterhalb der Streckgrenze auftreten, die durch eine Spannungskonzentration verursacht werden, deren Ursprung in intrinsischen Materialfehlern oder äußeren Kratzern liegt. Mit fortschreitender Schädigung bilden sich Rissstrukturen, die von verstreckten Fibrillen aufgespannt werden, bis es zum Versagen dieser Fibrillen kommt und sich der Riss ausbreitet. Dieser Schadensmechanismus des langsamen Risswachstums kann durch eine Vielzahl von Umgebungsmedien beschleunigt werden und wird dann als "environmental stress cracking" (ESC) bezeichnet. Eine international normierte Methode zur Validierung der Spannungsrissbeständigkeit von PE-HD Materialien ist der „Full Notch Creep Test“ (FNCT). Anhand von Bruchflächenauswertungen mittels Rasterelektronenmikroskopie und Laser-Scanning-Mikroskopie, werden die typischen Schädigungsstrukturen des ESC sichtbar. Die fibrillierten Strukturen des ESC auf der Bruchfläche von PE-HD ergeben sich besonders bei oberflächenaktiven wässrigen Umgebungsmedien. In Lösungsmittel-Umgebungsmedien, im Zusammenspiel mit PE-HD, kommt es aufgrund der plastifizierenden Wirkung zur Herabsetzung der Streckspannung und Bruchflächen aus dem FNCT veranschaulichen keine signifikanten Anzeichen des Schädigungsmechanismus ESC. T2 - 47. VDI-Jahrestagung Schadensanalyse 2021- Mediale und klimatische Beanspruchung von polymeren Produkten CY - Würzburg, Germany DA - 06.10.2021 KW - Umgebungsbedingter Spannungsriss KW - Polyethylen hoher Dichte KW - Full Notch Creep Test KW - Lösungsmittel KW - Oberflächenaktive wässrige Medien KW - Bruchflächenauswertung PY - 2021 AN - OPUS4-53665 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Alig, I. T1 - Charakterisierung von Behälterwerkstoffen aus Polyethylen N2 - Das langsame Risswachstum (slow crack growth, SCG) sowie der umgebungsbedingte Spannungsriss (environmental stress cracking, ESC) sind relevante Schädigungsmechanismen für teilkristalline Werkstoffe auf Basis von Polyethylen hoher Dichte (PE-HD). Der Vortrag gibt einerseits einen Überblick über die grundlegenden Struktur-Eigenschafts-Beziehungen in diesem Kontext, andererseits werden auch verschiedene praxisorientierte Prüfverfahren vorgestellt. Letztere wurden in gemeinsamen Forschungsprojekten von BAM und LBF mit dem Schwerpunkt Gefahrgutbehälter bzw. Pflanzenschutzmittel vergleichend untersucht und durch weitergehende Analytik ergänzt. T2 - 16. Tagung des Arbeitskreises Polymeranalytik Webkonferenz, Fraunhofer LBF und FGK CY - Online meeting DA - 22.03.2022 KW - Polyethylen KW - Full Notch Creep Test KW - Environmental Stress Cracking KW - Spannungsriss PY - 2022 AN - OPUS4-54547 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schartel, Bernhard T1 - Multifunctional Elastomer/Graphene Nanocomposites N2 - A few layer/multilayer graphene (MLG) with a specific surface area of BET=250 m2/g is proposed as an efficient multifunctional nanofiller for rubbers. The preparation method, i.e., ultrasonically-assisted solution mixing of master batches followed by two-roll milling, strongly influences the dispersion in the elastomeric matrix and is fundamental for the final properties. When homogenously dispersed, single stacks of only approximately 10 graphene sheets, with an aspect ratio of 34, work at low loadings, enabling the replacement of large amounts of carbon black (CB), an increase in efficiency, and a reduction in filler load. The appropriate preparation yielded nanocomposites in which just 3 phr are sufficient to significantly improve the rheological, curing, gas barrier properties, electrical and thermal conductivity, as well as mechanical properties of different rubbers, as shown for chlorine-Isobutylene-Isoprene rubber (CIIR), nitrile-butadiene rubber (NBR), natural rubber (NR), and styrene-butadiene rubber (SBR). 3 phr of MLG tripled the Young’s modulus of CIIR, an effect equivalent to 20 phr of CB. The stronger interactions between MLG and NR or SBR also resulted in a reduction in the elongation at break by 20% and 50%, respectively, while the same parameter was hardly changed for CIIR/MLG and NBR/MLG. CIIR/MLG and NBR/MLG were stiffer but just as defomable than CIIR and NBR. The strong reinforcing effect of 3 phr MLG was confirmed by the increase of greater than 10 Shore A in hardness. MLG reduces gas permeability, increases thermal and electrical conductivities, and retards flammability, the latter shown by the reduction in heat release rate in the cone calorimeter. We investigated MLG also as a synergist for reducing the aluminium trihydrate loading in flame retardant hydrogenated acrylonitrile-butadiene (HNBR), polybutadiene chloroprene (BR/CR), and chlorosulfonated polyethylene rubber(CSM). The higher the nanofiller concentration is, the greater the improvement in the properties. For instance, the permeability decreased by 30% at 3 phr of MLG, 50% at 5 phr and 60% at 10 phr, respectively. Moreover, the MLG nanocomposites improve stability of mechanical properties against the effects of weathering. In key experiments an increase in UV-absorption and a pronounced radical scavenging were proved as stabilizing mechanisms. In a nutshell, MLG is an efficient multifunctional nanofiller ready to be used for innovative rubber development. T2 - 19th European Polymer Congress, EPF 2022 CY - Prague, Czech Republic DA - 26.06.2022 KW - Graphene KW - Nanocomposite KW - Rubber KW - Elastomer PY - 2022 AN - OPUS4-55196 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Thuy, Maximilian T1 - Damage progression of environmental stress cracking affected by manufacturing process-induced microstructural orientation N2 - Currently, the Full Notch Creep Test (FNCT) [1] method is used by material suppliers and end users in industry for the approval of container and pipe materials based on high-density polyethylene (PE-HD). The resistance to environmental stress cracking (ESC) of the material is evaluated using the time to failure of the specimen in an aqueous solution of a detergent [2, 3]. Usually specimens made of sheets with isotropic material properties, manufactured by hot pressing, are employed in order to obtain intrinsic properties of the material in terms of ESC failure. In contrast, the processes used in manufacturing to form containers and pipes, such as extrusion blow molding or extrusion, impose anisotropic properties to the material. These are mostly due to a microstructural orientation (polymer chains or crystallites) [4]. Furthermore, the different cooling conditions significantly affect the size distribution of crystallites as well as the overall morphology. It is therefore essential to understand the influence of process-induced material characteristics on failure due to ESC. A large number of studies on material properties as a function of microstructural preferential orientation have already been conducted [5-7]. However, effects on ESC as the major failure mechanism of containers and pipes are still rather unexplored [8, 9]. The most important factor is whether primarily intramolecular high-strength covalent bonds or the substantially weaker intermolecular van der Waals forces are predominantly loaded. In addition to the widely established classification by time to failure, the strain or crack opening displacement (COD) provides valuable information about the evolution and progression of damage as a function of time [10, 11]. Optical strain measurement using digital image correlation allows the differences in COD for isotropic and different angles of orientation of anisotropic specimens to be discussed. Also, a post-fracture surface analysis provides clarification on the craze-crack mechanism of the ESC. These different ESC-related properties of extruded and hot-pressed specimens have been investigated at different environmental medium temperatures and different initial stresses to provide a broad characterization of the fracture behavior of PE-HD. T2 - 36th International Conference of the Polymer Processing Society CY - Montreal, Canada DA - 26.09.2021 KW - Environmental stress cracking KW - High-density polyethylene KW - Fracture behavior KW - Microstructural orientation PY - 2021 AN - OPUS4-53400 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schilling, Markus A1 - Marschall, Niklas A1 - Niebergall, Ute A1 - Böhning, Martin T1 - Modernizing FNCT data handling in polymer labs: Towards efficient management N2 - A streamlined Python-based workflow for transforming Full-Notch Creep Test (FNCT) data into organized, machine-actionable formats is presented. The workflow automates the conversion of raw FNCT data from classic CSV and Excel files into structured outputs that facilitate future semantic integration. Emphasizing practical data handling, the approach includes automation scripts for efficient data extraction, transformation, and storage, which culminate in well-ordered files. This transformation paves the way for potential semantic data integration and facilitates access for users with varying levels of digital experience to enhanced data management in polymer research and testing. KW - PE-HD KW - Full-Notch Creep Test (FNCT) KW - Environmental Stress Cracking (ESC) KW - Data Interoperability KW - FAIR Data KW - Semantic Data PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-637826 DO - https://doi.org/10.1016/j.commatsci.2025.114085 SN - 0927-0256 VL - 259 SP - 1 EP - 5 PB - Elsevier B.V. AN - OPUS4-63782 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Klippel, Andrea A1 - Hofmann-Böllinghaus, Anja A1 - Heydick, Lukas A1 - Piechnik, Kira A1 - Wu, Hongyi A1 - Köhler, Florian T1 - Experimental Analysis of Fire Behaviour in Pine Forests and Agricultural Fields Large Scale Tests conducted within the TREEADS Project N2 - In two large-scale tests fire spread mechanisms in vegetation ground fires were studied in a pine forest and a crop field. Both fires were ignited with a drip torch using a gasoline-diesel mix. The tests were part of the European TREEADS project, specifically in the research work from the German Pilot focusing on Saxony-Anhalt and Brandenburg. These regions are known for dry, sandy soil, with pine trees covering approximately 73% of forested areas in Brandenburg and 48% in Saxony-Anhalt. The results of both experiments make a substantial contribution to optimizing extinguishing methods and strategies and enhancing a continued wildfire research in Germany. The test areas included a 16 x 22 m plot in a Saxony-Anhalt pine forest and a 20 x 100 m plot on a crop field, with fires ignited along a line using a drip torch at both locations. Fire spread was monitored with video and IR cameras mounted on a drone. In the pine forest, 96 thermocouples and gas sensors were attached to trees and a mobile FTIR spectrometer was used for real-time gas measurements. A protective strip was created around the test area using a soil tiller and fire-retardant foam to prevent uncontrolled fire spread. The experiment showed a consistent temperature rise as the fire was ignited and spread. Thermocouple data captured detailed thermal dynamics, while tree-mounted gas sensors recorded significant fluctuations in combustible gases. Real-time gas spectra from the FTIR spectrometer enabled precise smoke analysis. Conducted in stable weather - 23°C, light wind, low soil moisture—this setup improved reproducibility, with a weather station monitoring temperature, humidity and wind conditions to assess fire-environment interactions. After ignition process the fire showed a slow spread and distinct combustion phases. Smouldering was more pronounced in areas with grasses and deadwood, highlighting vegetation-specific burn patterns critical to wildfire research. The experiment showed numerous smouldering and burning spots, with flames igniting and extinguishing repeatedly. However, flame height did not exceed half a meter. Due to substantial smoke production, visibility in the test field was limited and team members wore respirators to collect specific smoke gases such as benzene and formaldehyde for analysis. Field measurements showed flame temperatures exceeding 500°C. Toxic smoke gas concentrations of up to 238 ppm CO were measured, although precise gas capture appeared challenging due to wind turbulence. The second large-scale area in Nauen, a cut wheat field (stubble height approx. 30 cm) was burned, with fire spreading across approximately 700 m². A 20 m ignition line directed flames with the wind. Fire spread was observed using drones equipped with IR cameras. Experiments demonstrated how unpredictable and challenging it is to measure large outdoor fires. To enable a comprehensive theoretical and numerical description of fire dynamics in wildfires, it is essential to conduct further large-scale experiments. T2 - Interflam 2025, 16th International Fire Science and Engineering Conference CY - London, United Kingdom DA - 30.06.2025 KW - Wildfire PY - 2025 SP - 1435 EP - 1444 PB - Interscience CY - London AN - OPUS4-63926 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Anderson, Johan A1 - Chiva, Roman A1 - Dumont, Fabien A1 - Lalu, Octavian A1 - Hofmann-Böllinghaus, Anja T1 - Assessment of fire performance of facades in a round robin using the European approach N2 - In recent years, an experimental round robin of full-scale façade tests was conducted using the proposed new European approach for assessing the fire performance of façades. The initial results were used to develop a calibration scheme and to propose assessment criteria aligned with appropriate safety levels. During the project, a need emerged to evaluate the stability of the fire source and the Consistency of heat exposure. This paper addresses these concerns by comparing the mass loss rates across a series of tests and analysing averaged temperature readings at various locations on the façade. The findings indicate that the method demonstrates high stability in terms of mass loss rates and provides consistent and appropriate heat exposure. T2 - Interflam 2025, 16th International Fire Science and Engineering Conference CY - London, UK DA - 30.06.2025 KW - Facade systems KW - Testing PY - 2025 VL - 2025 SP - 562 EP - 572 PB - Interscience CY - London AN - OPUS4-63998 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Piechnik, Kira A1 - Hofmann-Böllinghaus, Anja A1 - Klippel, Andrea T1 - Characterization and assessment of smoke emissions from smouldering forest fires: a combined experimental and numerical approach N2 - This article builds upon the publication "Comprehensive Laboratory Study on Smoke Gases During the Thermal Oxidative Decomposition of Forest and Vegetation Fuels"1 in Fire and Materials, 2024, summarizing the experimental methodology and highlighting key findings. The study investigates the gas-phase composition of smoke emissions from forest and vegetation fuels. The study focuses on pine-dominated ecosystems in Eastern Germany, with the objective of improving the understanding of wildfire-related gaseous emissions, as a contribution to the German pilot activities within the EU Project TREEADS. Using a modified DIN tube furnace in a bench-scale setup, the investigation centers on gaseous emissions from five trees and two ground cover species, explicitly excluding particulate matter. T2 - Interflam 2025, 16th International Fire Science and Engineering Conference CY - London, UK DA - 30.06.2025 KW - Wildfire PY - 2025 SP - 288 EP - 294 PB - Interscience CY - London AN - OPUS4-63999 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hofmann-Böllinghaus, Anja A1 - Klippel, Andrea T1 - Vehicle Fires: Significant Fire Hazard in Transportation Infrastructure N2 - Vehicle fires in transportation infrastructure such as depots, car parks, tunnels and stations are a recurring phenomenon, with recent years witnessing an alarming number of severe incidents, particularly in vehicle depots. These fires often result in the total loss of both vehicles and buildings, with striking similarities in their progression. Analysis of recent fire events, including a study conducted for the German insurer Provinzial, shows that fires in bus depots, military facilities and car parks tend to spread rapidly and destructively. While building regulations vary across sectors and countries, the fire safety standards for interior materials in road vehicles remain globally harmonized and are based on outdated regulations such as FMVSS 302, which offer only a minimal level of protection. In contrast, materials used in trains, ships, and aircrafts must comply with significantly stricter fire safety standards, which may explain the relatively lower incidence of fires in these sectors. Common fire protection systems in depots, such as sprinklers and vents, often fail to account for the specific characteristics of automotive vehicles, including their watertight design and the rapid development of hot gas layers that accelerate fire spread. Insurance companies have begun to acknowledge these challenges. Given the high flammability, heat release and smoke toxicity of materials commonly used in vehicles, combined with the growing share of combustible plastics over the past decades, this paper argues for a paradigm shift. Instead of relying solely on inhancing building protection, introducing significantly stricter fire safety requirements for vehicle materials could offer a more effective and sustainable approach to safeguarding transportation infrastructure. Ongoing experimental investigations are being conducted to evaluate the reaction to fire behavior of various bus interior materials. These studies focus on the emission of toxic gases during combustion, with particular attention to substances exceeding critical AEGL thresholds. Materials such as polyurethane foams and hard plastics have shown significant variation in their smoke gas profiles, highlighting potential health and safety risks in fire scenarios. The research aims to support the development of safer material choices and regulatory measures. Upon completion of tests with additional materials, all findings will be published to ensure transparent and comprehensive reporting. T2 - Interflam 2025, 16th International Fire Science and Engineering Conference CY - London, United Kingdom DA - 30.06.2025 KW - Vehicle fires KW - Transportation PY - 2025 AN - OPUS4-63922 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Wu, Hongyi A1 - Buhk, Frederik A1 - Christiani, Ricardo A1 - Hofmann-Böllinghaus, Anja T1 - Influence of local vegetation on ignition and fire spread of vegetation fires-Experimental and numerical approach N2 - Within the framework of the European TREEADS project, Brandenburg and Saxony-Anhalt were designated as model regions. This designation facilitated the investigation of vegetation types, soil structure, and soil dryness. Brandenburg and Saxony-Anhalt are identified as the driest regions in Germany according to the annual mean soil moisture data. In these regions, 48% to 73% of the forests are composed of pine species. The soil profile is characterized by a relatively thin organic layer, measuring between 0.2 and 0.3 meters, underlain by sandy substrates. Consequently, surface and ground fires are more prevalent in these areas compared to other types of fires, such as crown fires. To investigate the influence of local vegetation, it goes through two aspects. One is laboratory study, the local vegetation samples were collected and tested for the thermal properties, such as activation energy, heat content and reaction kinetic of pyrolysis and dehydration. At the same time, small and medium scale combustion experiments were conducted to investigate the burning behavior. The other aspect is using the thermal properties as the input parameters for the development of numerical simulation in the computational fluid dynamics (CFD) tool. These models were then be validated with the combustion experiments, as a baseline for the further scaling up of the models, in order to investigate how the parameters influencing the fire spread in a large-scale case numerically. T2 - Interflam 2025, 16th International Fire Science and Engineering Conference CY - London, United Kingdom DA - 30.06.2025 KW - Wildfire PY - 2025 SP - 2221 EP - 2225 PB - Interscience CY - London AN - OPUS4-63932 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - THES A1 - Kaudelka, Sven T1 - Untersuchungen zur Brandentstehung und Brandausbreitung in Wohnungen N2 - Zur Bedarfsplanung von Feuerwehren in Städten in der Bundesrepublik Deutschland wurden im Jahr 1998 die Qualitätskriterien Hilfsfrist, Funktionsstärke und Erreichungsgrad für ein standardisiertes Schadensereignis erarbeitet. Das standardisierte Schadensereignis basiert auf Ergebnissen der O.R.B.I.T.-Studie aus dem Jahr 1978. Der dort dargestellte Rauchgas-temperaturverlauf für einen standardisierten Wohnungsbrand stellt Ergebnisse von Brandversuchen in einer Wohnung aus dem Jahr 1939 dar. Die zur Untersuchung herangezogenen Einrichtungsgegenstände bestanden dabei überwiegend aus cellulosehaltigen Materialien wie Holz und Papier. Die zunehmende Verwendung von Werkstoffen auf der Basis von Holz und Polymeren führt jedoch zu einer veränderten stofflichen Zusammensetzung von Einrichtungsgegenständen in Wohnungen. Im Rahmen der vorliegenden Dissertation wurde der Einfluss dieser veränderten stofflichen Zusammensetzung von gegenwärtigen Einrichtungsgegenständen auf den Verlauf von Raumbränden sowie auf die damit verbundene Stoff- und Energiefreisetzung während der Brandentstehungs- und Brandausbreitungsphase untersucht. Im Fokus der Untersuchung stand der Raum der Brandentstehung sowie ein angrenzender Raum. Die Ergebnisse zeigen, dass gegenwärtige Einrichtungsgegenstände sowohl im Raum der Brandentstehung als auch in dem angrenzenden Raum zu höheren Rauchgastemperaturen und -konzentrationen führen. Grund hierfür sind neben den höheren Wärmefreisetzungsraten auch die höheren Stoffausbeuten der in den gegenwärtige Einrichtungsgegenständen verwendeten Materialzusammensetzungen. Vor diesem Hintergrund zeigt sich, dass sich die auf Basis der O.R.B.I.T.-Studie definierten Standards nicht mehr als Grundlage zur Bedarfsplanung von Feuerwehren eignen. Diese können mit Hilfe der vorliegenden Ergebnisse einer Prüfung unterzogen werden, um den veränderten Brandverläufen im Rahmen einer zukünftigen Bedarfsplanung gerecht zu werden. N2 - In 1998 the quality criterias auxiliary period, functional force and degree of achievement for a standardized damage event were developed for the demand planning of fire brigades in cities in the Federal Republic of Germany. The definition of the standardized damage event is based on the results of the O.R.B.I.T.-study from 1978. The temperature-time curve for a standardized apartment fire presented in the above-mentioned definition study represents results of fire tests in an apartment from 1939. The furniture used for the investigation consisted mainly of cellulosic materials like wood and paper. However the increasing use of materials based on wood and polymers leads to an altered material composition of furniture in apartments. In the present dissertation the influence of this altered material composition of current furniture on the course of a fire in an apartment as well as on the associated mass and energy release during the ignition of a fire and fire propagation was investigated. The investigation focused on the room where the fire starts and on an adjacent room. As a result, it has been found that current furniture, both in the room where the fire starts and in an adjacent room, results in higher gas temperatures and higher gas concentrations. This is due to the higher heat release rates as well as the higher yields of the material compositions used in current furniture. Against this background, it becomes clear that the standards that were defined in the O.R.B.I.T.-study can no longer serve as the basis for demand planning of fire brigades. These should be reviewed with the help of the present results in order to adapt future demand planning to changing fire scenarios. T3 - BAM Dissertationsreihe - 164 KW - Stoffausbeute KW - Brandschutz KW - Brandentstehung KW - Brandausbreitung KW - Wärmefreisetzungsrate KW - Effektive Verbrennungswärme PY - 2019 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-479325 SN - 1613-4249 VL - 164 SP - I EP - 234 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-47932 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Nandish, Ranjith A1 - Knaust, Christian A1 - Hofmann-Böllinghaus, Anja A1 - Gnutzmann, Tanja A1 - Zehfuß, Jochen T1 - Simulation of wood pyrolysis with component-based mechanism N2 - This paper presents a comprehensive fire simulation study that models the pyrolysis process of beech wood using kinetic parameters with the Fire Dynamics Simulator (FDS). The kinetic methodology is based on the application of these kinetic parameters to govern the underlying pyrolysis reactions. The primary objective was to numerically model the pyrolysis process for beech wood using both single-component (single-step, single reaction scheme) and multi-component (single-step, multi-reaction scheme) kinetic reaction schemes. The accuracy of the numerical model was validated by comparing FDS simulation results with experimental data obtained from thermogravimetric analysis (TGA) and cone calorimeter tests. This approach aids in identifying reliable kinetic reaction input parameters for modelling wood fires. A case study was included to demonstrate the implementation of the kinetic reaction schemes. Numerical results from the TGA simulations for the small-scale pure cellulose test using the single-component approach exhibit consistency with the experimental data. Furthermore, the results demonstrated that the multi-component approach more accurately replicates the shape of the experimental curve for beech wood compared to the single-component approach. However, discrepancies in the tail regions of the curves obtained from the FDS simulations showed the need for further improvement in the modelling approach, particularly regarding the exclusion of char oxidation reactions, which needs to be investigated further. KW - Simulation KW - Wood PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-639272 DO - https://doi.org/10.1007/s00231-025-03571-7 SN - 0947-7411 VL - 61 IS - 6 SP - 1 EP - 14 PB - Springer Science and Business Media LLC AN - OPUS4-63927 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Geoerg, Paul A1 - Schumann, Jette A1 - Holl, Stefan A1 - Holl, Maik A1 - Hofmann-Böllinghaus, Anja T1 - The influence of individual impairments in crowd dynamics N2 - The importance of empirical relations to quantify the movement of pedestrians through a facility has increased during the last decades since performance-based design methods became more common. Bottlenecks are of special interest because of their importance for egress routes and as they result in a reduced capacity. The empirical relations as the density-dependent movement speed or flow rate were derived by studies under laboratory conditions, which were usually conducted with populations of homogeneous characteristics forbetter control of influencing variables. If individual characteristics of a crowd become more heterogeneous, individuals were forced to adapt their individual movement and control individual manoeuvring. These unintended interactions lead to a different shape of the fundamental empirical relations. Here, we present results from a movement study under well-controlled boundary conditions in which participants with and without different characteristics of disabilities participated. To consider the effect of different heterogeneities on the capacity of a facility, fundamental diagrams are generated using the Voronoi method. If participants with visible disabilities (such as using assistive devices) are part of a crowd, significant differences relating to the shape of the empirical Relations and the capacities are found. This indicates that the heterogeneity of a Population leads to an increased interpersonal interaction which results in influenced movement characteristics. KW - Engineering egress data KW - Heterogeneity KW - Human behaviour KW - Movement characteristics KW - Pedestrian dynamics PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-508943 DO - https://doi.org/10.1002/fam.2789 SN - 0308-0501 VL - 45 IS - 4 SP - 529 EP - 542 PB - Wiley Online Libary CY - New Jersey, USA AN - OPUS4-50894 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hofmann-Böllinghaus, Anja A1 - Klippel, Andrea A1 - Gnutzmann, Tanja A1 - Kaudelka, Sven A1 - Rabe, Frederik T1 - Influence of modern plastic furniture on the fire development in fires in homes: large-scale fire tests in living rooms N2 - About 80% of all fire fatalities in Germany occur because of fires in homes. It has been known for some time that modern materials (synonym for materials consisting mostly of synthetic polymers) tend to burn differently from older materials (synonym for materials consisting mostly of fibrous cellulosic substances) and it has been acknowledged that the amount of combustible plastics in homes has increased significantly over the last decades. To investigate the influence of modern furniture and ventilation conditions of fires in homes, a series of four large-scale tests in two Living rooms (LRs) with adjacent rooms (ARs) was performed by BAM and the Frankfurt fire service. Two LRs, one with older furniture and one with modern furniture, were tested twice each. Each test started with the ignition of a paper cushion on an upholstered chair. The influence of modern materials on the fire development was investigated, as well as the influence of the ventilation on the fire development. In all settings, an upholstered chair was the first burning item. Results of the test series show that fires in rooms with modern furniture develop faster than fires in rooms with older furniture. This is true for temperature development in the rooms as well as for smoke production. KW - Room fire KW - Furniture KW - Modern KW - Gas analysis KW - Smoke PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-527568 DO - https://doi.org/10.1002/fam.2934 VL - 45 IS - 1 SP - 155 EP - 166 PB - Wiley CY - London AN - OPUS4-52756 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hofmann-Böllinghaus, Anja A1 - Klippel, Andrea A1 - Piechnik, Kira T1 - Vehicle fires: significant fire hazard in transportation infrastructure N2 - The zeolitic imidazole framework-8 (ZIF-8) is a crystalline porous material that has been widely employed as template to fabricate porous nitrogen-doped carbons with high microporosity via thermal treatment at high temperatures. The properties of the carbon scaffold are influenced by the pore structure and chemical composition of the parent ZIF. However, the narrow pore size distribution and microporous nature from ZIF-8 often results in low mesopore volume, which is crucial for applications such as energy storage and conversion. Here we show that insertion of N-heterocyclic amines can disrupt the structure of ZIF-8 and dramatically impact the chemical composition and pore structure of the nitrogen-doped carbon frameworks obtained after high-temperature pyrolysis. Melamine and 2,4,6-triaminopyrimidine were chosen to modify the ZIF-8 structure owing to their capability to both coordinate metal ions and establish supramolecular interactions. Employing a wide variety of physical characterization techniques we observed that melamine results in the formation of a mixed-phase material comprising ZIF-8, Zn(Ac)6(Mel)2 and crystallized melamine, while 2,4,6-triaminopyrimidine induces the formation of defects, altering the pore structure. Furthermore, the absence of heterocyclic amine in the ZIF-8 synthesis leads to a new crystalline phase, unreported to date. The thermal conversion of the modified ZIFs at 1000 °C leads to nitrogen-doped carbons bearing Zn moieties with increased surface area, mesopore volume and varying degree of defects compared to ZIF-8 derived carbon. This work therefore highlights both the versatility of heterocyclic amines to modify the structure of framework materials as well as their role in tuning pore structure in nitrogen-doped carbons, paving the way to targeted design of high-performance electrodes for energy storage and conversion. T2 - Interflam 2025, 16th International Fire Science and Engineering Conference CY - London, United Kingdom DA - 30.06.2025 KW - Vehicle fires PY - 2025 SP - 1291 EP - 1298 PB - Interscience CY - London AN - OPUS4-63924 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Müller, Simon T1 - Ein Modell zur Ausbreitung von Waldbränden - schnellere Vorhersagen durch den Einsatz von maschinellem Lernen, Fernerkundung und Copernicus-Daten N2 - Weltweit stellen Waldbrände eine große Bedrohung für Umwelt, Wirtschaft und menschliches Leben dar. Der fortschreitende Klimawandel verstärkt Trockenheit und Dürre, wodurch die Größe und Intensität von Waldbränden sowie das daraus resultierende Gefahrenpotential zusätzlich erhöht werden. Um im Risikofall eine schnelle und effektive Waldbrandbekämpfung zu gewährleisten, sollen Einsatzkräfte in Zukunft von KI-basierten Ausbreitungsmodellen unterstützt werden. Der Einsatz von maschinellem Lernen ermöglicht dabei schnelle und zielgerichtete Ausbreitungsvorhersagen in Echtzeit, die in den Prozess der Brandbekämpfung als zusätzliche Information einfließen können. Im Rahmen des durch das EU-Förderprogram Horizon 2020 finanzierte Projekt TREEADS wird ein solches Modell für Europa entwickelt. Dazu wird mit verschiedenen Satellitendaten des Copernicus-Programms und der NASA ein auf räumlicher und zeitlicher Ebene aufgelöster Datensatz zu europäischen Waldbränden aufgebaut. Zu den erfassten Waldbränden werden wichtigen Faktoren, die Einfluss auf die Brandausbreitung haben, ergänzt. Dazu gehören das von Copernicus bereitgestellte, digitale Geländemodell Europas und verschiedene, von Sentinel-2 Messungen abgeleitete Informationen zu Vegetation und Landnutzung. Dieser 2D-Trainingsdatensatz zu realen Waldbränden wird durch die zeitlich hochaufgelösten, meteorologischen Reanalyse-Produkte – Copernicus European Regional ReAnalysis (CERRA) und ERA5-Land – vervollständigt und ist die Grundlage für ein Modell zur Ausbreitungsvorhersage von Waldbränden. Methoden des Maschinellen Lernens können komplexe Muster in den gesammelten Daten erkennen und so zu einer verbesserten Vorhersage der Brandausbreitung beitragen. Die vielfältigen, von Copernicus bereitgestellten Daten sind dabei ein unabdingbarer Bestandteil des Modells, mit dem den Einsatzkräften ein zusätzliches Tool für den effizienten Einsatz ihrer limitierten Ressourcen zur Verfügung steht. T2 - Nationales Forum für Fernerkundung und Copernicus 2024 CY - Berlin, Germany DA - 19.03.2024 KW - Maschinelles Lernen KW - Waldbrand KW - Geoinformatik KW - Fernerkundung PY - 2024 AN - OPUS4-59840 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Piechnik, Kira A1 - Heydick, Lukas A1 - Hofmann-Böllinghaus, Anja A1 - Klippel, Andrea T1 - Comprehensive laboratory study on smoke gases during the thermal oxidative decomposition of forest and vegetation fuels N2 - AbstractThis study investigates the composition of smoke gases in forest and vegetation samples to draw conclusions about the actual smoke gas composition during wildfires. The focus is particularly on regions with extensive pine forests, like in Eastern Germany. The relevance of smoke gases is well illustrated by the example of wildfires in Québec, influencing air quality in New York, in 2023. By employing a modified DIN tube furnace, a bench‐scale test set‐up, the research emphasizes the examination of smoke composition from tree species and ground cover, prioritizing gases while disregarding particles. Key smoke gases are identified as CO, CO2, SO2, HCN, C3H4O (acrolein) and CH2O (formaldehyde) and their concentrations are compared with Acute Exposure Guideline Levels (AEGL) limits. Acknowledging the limitations of AEGL usage and the problem with direct quantitative comparison of toxicant concentrations (cf. ISO 29903‐1:2020), the study highlights variations in smoke composition across different samples. The results of the studies reveal a significant disparity in CO concentration between dry and fresh pine needles. Frequently, the AEGLs of key gases are exceeded significantly. The elemental analysis of the barks indicates distinct differences in composition, reflecting in the concentrations of smoke gases. The ratio of 1 mole of substance turnover to the identified key components will be used to determine input parameters for the subsequent numerical simulation. KW - Forest KW - Wildfire KW - Ignition PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-617744 DO - https://doi.org/10.1002/fam.3253 SP - 1 EP - 12 PB - Wiley online library AN - OPUS4-61774 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Piechnik, Kira A1 - Hofmann-Böllinghaus, Anja A1 - Klippel, Andrea T1 - Self‐ignition of forest soil samples demonstrated through hot storage tests N2 - AbstractThe increasing threat of forest fires on a global scale is not only a matter of concern due to the potential harm they may cause to both human and animal life but also due to their significant role in exacerbating climate change. In light of these circumstances, one might inquire as to whether forest soil can self‐ignite and, if so, under what conditions and at what temperatures this phenomenon may occur. This question is being addressed in the German pilot “Fire science of wildfires and safety measures” of the EU project TREEADS, and the first results are presented below. The importance of basic research into the self‐ignition of forest soil cannot be underestimated, as it provides crucial knowledge to prevent forest fires and protect human and animal health. Furthermore, mitigating the occurrence of forest fires can also play a role in reducing greenhouse gas emissions, contributing to global efforts to combat climate change. The procedure of the hot storage test is an effective means of determining whether a material can self‐ignite. During the investigation of six soil samples, it was found that five of them were indeed capable of self‐ignition. In addition to determining whether the material ignites, the modified hot storage test also analyzed the resulting smoke gases and measured their concentration. The research question of whether regional forest soil is capable of self‐ignition can be answered with yes based on these initial tests. Further experiments are needed to determine if self‐ignition causes forest fires. KW - FTIR KW - Hot storage KW - Ignition KW - Soil KW - Wildfire PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-594617 DO - https://doi.org/10.1002/fam.3198 SN - 1099-1018 VL - 48 IS - 4 SP - 495 EP - 507 PB - Wiley CY - New York, NY AN - OPUS4-59461 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Manes, M. A1 - El Houssami, M. A1 - Campbell, R. A1 - Sauca, A. A1 - Rush, D. A1 - Hofmann-Böllinghaus, Anja A1 - Andersson, P. A1 - Wagner, P. A1 - Veeneklaas, J. A1 - van Hees, P. A1 - Guillaume, E. T1 - Closing Data Gaps and Paving the Way for Pan-European Fire Safety Efforts: Part I—Overview of Current Practices for Fire Statistics N2 - The analysis of the current state of fire statistics and data collection in Europe and other countries is needed to increase awareness of how fire incidents affect buildings and to support pan-European fire prevention and fire mitigation measures. The terminology and data collected regarding fire incidents in buildings in the EU Member States were mapped to obtain meaningful datasets to determine common terminology, collection methodology, and data interpretation system. An extensive literature review showed that fire data collection systems have been instrumental in informing firefighting strategies, evidence-based planning, prevention, and educational programmes. Differences and similarities between fire data collection systems were also investigated. The amount and quality of the information in fire statistical recording systems appear to be influenced by the complexity and structure with which the data are collected. The analysis also examined the existing fire statistics in the EU Member States and a few other countries. Finally, a detailed investigation of the number of fires, fire deaths, and injuries from 2009 to 2018 in several countries was examined based on data from a report by CTIF. The trends showed differences attributable to the existing fire statistical practices in terms of terminology and data collection, and interpretation. Part II proposes a common terminology for selected fire statistical variables. The results provide relevant information regarding fire safety at the European level and should be used to guide the development of more uniform fire statistics across Europe. KW - Fire statistics KW - European project PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-575711 DO - https://doi.org/10.1007/s10694-023-01415-6 SN - 1572-8099 SP - 1 EP - 44 PB - Springer CY - Heidelberg AN - OPUS4-57571 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - El Houssami, M. A1 - Försth, M. A1 - Fredriksson, H. A1 - Drean, V. A1 - Guillaume, E. A1 - Hofmann-Böllinghaus, Anja A1 - Sandinge, A. T1 - Fire safety of interior materials of buses N2 - This study provides an analysis on the fire safety of passengers and the fire protection of coaches and buses. A brief review of major bus fire incidents, an overview of current regulations in Europe, and their limitations are presented. The study finds that the current small-scale fire test methods described in UN ECE Reg No. 118 need to be replaced by test methods that can assess the reaction to fire of materials when exposed to ignition sources of varying sizes. To address these shortcomings, the study proposed an expert recommendation to update the material fire safety requirements and testing for buses. Additional measures are proposed, derived from objectives and strategies applied in other transport sectors, and can be tested through existing European and international standards, which are widely used by several industries. These measures aim to extend the time with tenable conditions for a safe evacuation in case of fire, reduce the degree of damage to buses, reduce the risk for fast and excessive thermal exposure on modern energy carriers needed for a more sustainable transport sector. KW - Fire KW - Bus interior materials KW - Rregulations PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-575700 DO - https://doi.org/10.1002/fam.3134 SN - 1099-1018 SP - 1 EP - 15 PB - Wiley CY - London AN - OPUS4-57570 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Manes, M. A1 - Sauca, A. A1 - El Houssami, M. A1 - Andersson, P. A1 - McIntyre, C. A1 - Campbell, R. A1 - Rush, D. A1 - Hofmann-Böllinghaus, Anja A1 - Wagner, P. A1 - Leene, M. A1 - Oberhagemann, D. A1 - Jomaas, G. A1 - Grone, F. A1 - Guillaume, E. T1 - Closing Data Gaps and Paving the Way for Pan-European Fire Safety Efforts: Part II—Terminology of Fire Statistical Variables N2 - A well-defined terminology of fire-related variables is important for correct analyses and supporting knowledge-based decisions regarding the evaluation of building fires at the European level. After developing an overview of current practices for fire statistics in Part I, the terminology used and the data collected by the EU Member States and eight other countries regarding fire incidents, property damage and human losses were mapped to increase awareness of their practice and support a comprehensive assessment of several fire statistical datasets. A questionnaire was distributed to relevant authorities responsible for the collection, elaboration/analysis, and fire statistical data publications to define and select the essential variables for an appropriate fire assessment and fire incident description. Based on the results of the questionnaire able to identify the essential fire statistical variables and a detailed analysis of current definitions adopted in the fire statistics of the EU Member States and other countries, a common terminology is proposed to collect the necessary data in the EU Member States and obtain meaningful datasets based on standardised terms and definitions. The results will generate essential outputs to move towards harmonised fire statistics at the EU level and contribute to an appropriate analysis able to improve fire prevention and fire mitigation in building fires. KW - Fire statistics PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-575725 DO - https://doi.org/10.1007/s10694-023-01408-5 SN - 1572-8099 SP - 1 EP - 32 PB - Springer CY - Heidelberg AN - OPUS4-57572 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Klippel, A. A1 - Hofmann-Böllinghaus, Anja A1 - Gnutzmann, Tanja A1 - Piechnik, K. T1 - Reaction-to-fire testing of bus interior materials: Assessing burning behaviour and smoke gas toxicity N2 - Although fire safety regulations for buses have been adapted in recent years regarding, for example, fire detection and engine fire suppression systems, the changes in regulations for bus interior materials are minimal. A comparison of fire safety regulations for interior materials in other transport sectors for trains, ships or aircraft reveals a much lower level of requirements for bus materials. Although repeated bus accidents as well as fire statistics show the danger a bus fire can pose to passengers. In particular, the combination of a fire incident and passengers with reduced mobility led to severe disasters in Germany and other European countries. To enhance the fire safety for passengers, the interior bus materials are crucial as the fire development in the bus cabin determines whether escape and rescue is possible. Against this background, bus interior materials were tested in different fire test scenarios. Measurement of a wide variety of parameters, for example, the mass loss, ignition time, smoke gas composition, heat release rate among others were carried out. Tested materials complied to the newest set of requirements. For this purpose, interior materials and their components had to be identified according to their chemical structure. Parts of the tests were funded by BASt (Federal Highway Research Institute) in the project 82.0723/2018. Experimental results show reaction-to-fire behaviour which lead to very limited times for escape and rescue in case of fire in a bus cabin. Based on the studies on fire behaviour and toxicity assessment, recommendations for improved fire safety regulations for interior materials could be made. KW - Burning behaviour KW - Bus interior materials KW - Cone calorimeter KW - DIN tube furnace KW - FTIR spectroscopy KW - Reference values KW - Smoke toxicity PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-576085 DO - https://doi.org/10.1002/fam.3108 SN - 1099-1018 VL - 47 IS - 5 SP - 665 EP - 680 PB - Wiley CY - New York, NY AN - OPUS4-57608 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rogge, Andreas T1 - Large scale impact tests with reinforced concrete plates for impact safety N2 - As part of a nuclear safety research project, large-scale impact tests were conducted on reinforced concrete slabs to investigate the structural integrity of containment structures under aircraft crash scenarios. The aim was to experimentally validate numerical models for both hard and soft impact conditions. Using a drop tower, concrete slabs were subjected to controlled impacts with a 404 kg impactor dropped from a height of 9.5 meters. The tests included force measurements, photogrammetric evaluations, and 3D scans to analyze deformations and damage. A total of six impact experiments were performed (2x hard impact, 2x combined hard/soft impact). The results provide a robust basis for advancing safety assessments of nuclear facilities. T2 - SMiRT28 - 28th International Conference on Structural Mechanics In Reactor Technology CY - Toronto, Canada DA - 10.08.2025 KW - Experimental mechanics KW - Aircraft crash scenario KW - Coupled impact loading PY - 2025 AN - OPUS4-64126 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Eggert, Lara T1 - Possibilities in the seawater laboratory on Germany’s North Sea coast N2 - The aim of the seawater laboratory is to observe and test corrosion and corrosion protection systems in real seawater in a fully equipped electrochemistry laboratory. The unique selling point is a seawater bypass, which makes it possible to colonize and maintain salt water or brackish water growth (bacteria, algae, krill, shell, fungi, etc.). The annual course of the marine environment can be observed. Issues like the selection of materials or simulation of corrosion and corrosion protection systems in real seawater can be studied. As an example, the corrosive influence of the real seawater on immersed steel (S355) and a bimetallic cell of S355 and stainless steel (1.4362) is monitored over one year by measuring potentials and cell currents. Experiments were performed to study the possible corrosion accelerating effects like bimetallic and microbiologically influenced corrosion. These can be run under two different conditions to simulate light and dark environments. The results can help to understand enhanced corrosion rates of steel mounted on offshore wind power plant. Moreover, the roof of the seawater laboratory is also an atmospheric exposure site and will be continuously sampled in the coming years. T2 - EuroCorr 2025 CY - Stavanger, Norway DA - 07.09.2025 KW - Meerwasserlabor KW - Maritime Korrosion KW - Atmosphärische Korrosion PY - 2025 AN - OPUS4-64128 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Mirza Abdul Basit, Beigh T1 - Sustainable Reproduction of Ornamental Glass for Historical Building Retrofitting: A Dual-Material Approach Using Refractory and Alkali-activated Concrete N2 - The preservation of ornamental glasswork in historical architecture—spanning Baroque churches, Victorian theatres, Art Deco structures, and colonial-era palaces—faces a critical challenge: reproducing small, customized batches of ornamental glass with period-accurate patterns. Traditional industrial methods, optimized for mass production, are economically and environmentally unsustainable for heritage projects. This study proposes a dual-material mould system combining refractory concrete and alkali-activated binders to address these limitations, offering a solution that balances historical fidelity, thermal resilience, and sustainable practices. T2 - 4th International Conference on Sustainable Building Materials - ICSBM CY - Eindhoven, Netherlands DA - 10.08.2025 KW - Ornamental glass KW - Alkali-activated refractory materials KW - Glass slumping KW - Thermal resilience PY - 2025 AN - OPUS4-64157 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Jafari, Abbas T1 - Geometric Parameterization and Analysis of Thin-Walled Additively Manufactured Triply Periodic Minimal Surface Structures N2 - Additive manufacturing (AM) has emerged as a transformative technology for fabricating meta-materials with intricate geometries and tunable macroscopic properties, enabling broad applications across fields such as engineering and biomedicine. A well-known challenge in harnessing the full potential of AM is the tendency of the process to introduce geometric imperfections into printed objects. Such deviations can impact the desired mechanical behavior and performance, which is typically predicted using physicsbased simulations that assume idealized nominal geometries. Therefore, analyzing the “as-is” geometry of AM structures is crucial to ensure the reliability of printed components and their simulators [1, 2]. This work centers on the geometric analysis of thin-walled additively manufactured Triply Periodic Minimal Surface (TPMS) structures. We demonstrate the sensitivity of solid-element-based Finite Element (FE) models to geometric imperfections, highlighting the need to incorporate geometric details of asprinted objects into simulations. To manage the extensive geometric variability and deviations inherent in printed specimens, we propose a regularization approach based on two key geometric descriptors, namely “mid-surface position” and “wall thickness”. These features offer two benefits. First, they provide meaningful metrics for quantitatively comparing printed and nominal geometries. Secondly, they enable the construction of shell-based FE models for thin-walled structures, enriched by the features of the actual printed geometry. One advantage of such shell-based FE models is its significantly lower computational cost compared to a solid FE model, enabling a more efficient incorporation of uncertainty within the estimated geometric features. We demonstrate the procedure for extracting and estimating the two geometric parameters for real printed specimens, leveraging computer tomography (CT) imaging and the derived Signed Distance Field. The advantages of integrating these estimated geometric features into FE simulations are demonstrated through a series of analyses based on real printed specimens. T2 - SIM-AM 2025 - The Fifth International Conference on Simulation for Additive Manufacturing CY - Pavia, Italy DA - 09.09.2025 KW - Geometric parameterization KW - Triply periodic minimal surface (TPMS) KW - Thin-walled structures KW - Shell-based finite element analysis PY - 2025 AN - OPUS4-64180 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Jafari, Abbas T1 - Bayesian parameter identification of nonlinear constitutive laws with strain localization N2 - Mechanical structures are frequently simulated by numerical models developed on the basis of physical laws. Such simulations are significantly influenced by the incorporated material models, which often suffer from considerable uncertainty. These uncertainties are, in general, derived from inadequate physical laws, unrealistic assumptions, and imprecise simplifications. Bayesian techniques are often employed to resolve such uncertainties based on experimental data, particularly those related to model parameters and measurement inaccuracies. This work focuses on the Bayesian parameter identification of a parameterized physics-based constitutive law that is used to describe strain localization. The proposed inference scheme relies on the use of measured integrated forces and full-field displacements. The former essentially are aggregated external forces measured at structural level over certain sub-boundaries. The full field displacements are assumed to be obtained from monitoring procedures, such as Digital Image Correlation (DIC), which are able to return dense observations. As a central idea of the proposed framework, strain localization effects are directly incorporated into the model by introducing Dirichlet constraints from full-field displacements. The objective function to be minimized is then a metric of the discrepancy between the model’s internal forces and the measured aggregated forces. Based on this objective function, a Bayesian inverse problem is formulated and solved using a variational Bayesian method, originally proposed in. The inference scheme further addresses the uncertainty of measured displacements applied as Dirichlet constraints. We verify the proposed framework on two virtual examples, utilizing a gradient damage constitutive law that accounts for strain localization. Further details of the methods and the examples can be found in. T2 - COMPLAS 2025 - XVIII International Conference on Computational Plasticity CY - Barcelona, Spain DA - 02.09.2025 KW - Bayesian inference KW - Constitutive law KW - Full-field measurements PY - 2025 AN - OPUS4-64179 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schepers, Winfried T1 - Die Courant-Friedrichs-Lewy-Bedingung als Genauigkeits- und Stabilitätsbedingung bei FEM-Berechnungen zur Wellenausbreitung N2 - Bei numerischen Berechnungen zur Wellenausbreitung im Zeitbereich mit der FE-Methode wird sehr häufig die Courant-Friedrichs-Lewy-Bedingung als zwingend einzuhaltende Bedingung für das Zeitschrittintegrationsverfahren genannt. Darin wird gefordert, dass eine sich ausbreitende Welle innerhalb eines Zeitschritts nicht mehr als die Distanz zum nächstgelegenen Knotenpunkt zurücklegen dürfe. Dies lässt erwarten, dass es sich um eine physikalisch begründbare Bedingung handelt. Es ist jedoch in der Literatur zu beobachten, dass nicht weiter ausgeführt wird, ob es sich um eine Genauigkeits- oder um eine Stabilitätsbedingung handelt, und ob sie für alle Zeitschrittverfahren einzuhalten ist oder nur für einige spezielle. Auch werden entsprechende Aussagen ohne weiteren Quellennachweis gemacht. Dieser Beitrag erläutert zunächst die Fragestellung, der Courant et al. in der Originalveröffentlichung von 1928 nachgegangen sind, und zeigt auf, welche Bedeutung die von ihnen gefundene Beziehung für die dort untersuchte Fragestellung hat. Anschließend wird der Frage nachgegangen, inwieweit die dort gewonnenen Erkenntnisse auf FEM-Berechnungen übertragen werden können. Die Betrachtung der Stabilitätsbedingungen verschiedener Zeitschrittintegrationsverfahren im Kontext von FEM-Berechnungen in der Strukturdynamik zeigt anschließend, dass es sich bei der CFL-Bedingung nicht um eine physikalisch begründbare Beziehung, sondern um eine rein numerische Bedingung ohne physikalischen Hintergrund handelt. T2 - 19. D-A-CH Tagung Erdbebeningenieurwesen und Baudynamik CY - Vienna, Germany DA - 18.09.2025 KW - Numerische Methoden KW - Zeitschrittintegration KW - Verkehrserschütterungen PY - 2025 SN - 978-3-200-10710-6 DO - https://doi.org/10.34726/10599 SP - 259 EP - 264 PB - Österreichische Gesellschaft für Erdbebeningenieurwesen und Baudynamik (OGE) CY - Wien AN - OPUS4-64191 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schepers, Winfried T1 - Kritische Betrachtung der Impedanzfunktionen harmonisch angeregter Fundamente N2 - In den aktuellen Entwürfen des Eurocode 8 Teil 5 (FprEN 1998-5:2024) und auch des Euro-codes 7 Teil 3 (E DIN EN 1997-3:2022-10) werden Formeln für die Steifigkeiten eines Hal-braums mit einem darin eingebetteten starren masselosen Rechteckfundament gegenüber einer harmonischen Anregung angegeben. Die Formeln sind im Wesentlichen eine Kombination der Ergebnisse der Veröffentlichungen von Gazetas (1991) und Pais et al. (1988) über Forschungs-arbeiten, die in den 1980er Jahren durchgeführt wurden. Sie basieren auf numerischen Berech-nungen, deren Ergebnisse durch Ausgleichskurven approximiert wurden. Eine genauere Analyse der den Formeln zugrunde liegenden Veröffentlichungen zeigt einige Inkonsistenzen zwischen Eurocodes und den ursprünglichen Veröffentlichungen, deren Ursache nicht ohne weiteres er-kennbar ist. Darüber hinaus werden in den Eurocodes nur frequenzunabhängige Steifigkeiten angegeben. Das führt zu der Frage, wie verlässlich die Formeln sind. An zwei Beispielen wird nachfolgend die Notwendigkeit einer kritischen Verwendung der Impedanzfunktionen gezeigt. T2 - 19. D-A-CH Tagung Erdbebeningenieurwesen und Baudynamik CY - Vienna, Austria DA - 18.09.2025 KW - Impedanzen KW - Wellenausbreitung KW - Erschütterungen PY - 2025 SN - 978-3-200-10710-6 DO - https://doi.org/10.34726/10599 SP - 245 EP - 246 PB - Österreichische Gesellschaft für Erdbebeningenieurwesen und Baudynamik (OGE) CY - Wien AN - OPUS4-64187 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schepers, Winfried T1 - Kritische Betrachtung der Impedanzfunktionen harmonisch angeregter Fundamente N2 - In den aktuellen Entwürfen des Eurocode 8 Teil 5 (FprEN 1998-5:2024) und auch des Euro-codes 7 Teil 3 (E DIN EN 1997-3:2022-10) werden Formeln für die Steifigkeiten eines Hal-braums mit einem darin eingebetteten starren masselosen Rechteckfundament gegenüber einer harmonischen Anregung angegeben. Die Formeln sind im Wesentlichen eine Kombination der Ergebnisse der Veröffentlichungen von Gazetas (1991) und Pais et al. (1988) über Forschungs-arbeiten, die in den 1980er Jahren durchgeführt wurden. Sie basieren auf numerischen Berech-nungen, deren Ergebnisse durch Ausgleichskurven approximiert wurden. Eine genauere Analyse der den Formeln zugrunde liegenden Veröffentlichungen zeigt einige Inkonsistenzen zwischen Eurocodes und den ursprünglichen Veröffentlichungen, deren Ursache nicht ohne weiteres er-kennbar ist. Darüber hinaus werden in den Eurocodes nur frequenzunabhängige Steifigkeiten angegeben. Das führt zu der Frage, wie verlässlich die Formeln sind. An zwei Beispielen wird nachfolgend die Notwendigkeit einer kritischen Verwendung der Impedanzfunktionen gezeigt. T2 - 19. D-A-CH Tagung Erdbebeningenieurwesen und Baudynamik CY - Vienna, Germany DA - 18.9.2025 KW - Impedanzen KW - Wellenausbreitung KW - Erschütterungen PY - 2025 AN - OPUS4-64188 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schartel, Bernhard T1 - Flame Retardancy Features Sustainability Food for Thought, Fake Fiction, and Future N2 - Sustainability (environmental conservation for the economic welfare and prosperity for all) would revolutionise the plastics industry were it to become predominant practice as a linear, fossil-fuel–based economy is switched to a carbon circular one. Hence, the innovative field of flame-retardant polymeric materials should lend its strength to drive this challenge. Visionary solutions are proposed to inspire us, while the implementation of economically feasible concepts take us forward into the future. A critical overview of current trends is presented, using examples from the literature and our own recent projects. The examples lead from the use of natural materials with some intrinsic flame retardancy, via biocomposites, to using renewable sources for flame retardants. Natural flame retardants and adjuvants are highlighted, motivating our vision. Some of the visionary approaches such as flame-retardant poly(limonene carbonate) or wastewater phosphorus enriched micro algae as a sustainable flame retardant are rather innovative. Further, natural material streams find their way into polymer mass production as fillers, adjuvants, or renewable educt sources; industrial waste streams open the door to sustainable solutions, because they avoid competition for land with farming or virgin forests. Remarks will address recycling, flame retardant vitrimers are potential materials for recyclable thermosets. Only convincing property profiles will prevail both for exploiting renewable sources and circular design; sustainability must not be merely tolerated as an additional demand but should instead be recognized as a solution ensuring our economic welfare now and in the future. Acknowledgement: Funding: BMBF WTZ 01DN16040, DFG Scha 730/19 u. 20, VW-Stiftung: Experiment 97437, BMBF KMU Innovativ 031B1289B. People: A Battig, R Bhatia, J Chacon Castro, M Dudziak, SF Falkenhagen, FR Gleuwitz, a.o. (BAM) and G Sánchez Olivares (CIATEC), R Dey (Constructor University), A Greiner (Bayreuth), a.o. T2 - 19th Bayreuth Polymer Symposium CY - Bayreuth, Germany DA - 21.09.2025 KW - Poly(limonene carbonate) KW - Flame retardant biocomposites KW - Wastewater phosphorus enriched micro algae KW - Non-vegan flame retardant KW - Flame retardant vitrimers KW - Bio-based flame retardant PY - 2025 AN - OPUS4-64204 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Seifert, Lando A1 - Eggert, Lara T1 - Weathering Campaigns in the North Sea for an Offshore Power-to-X Project N2 - The poster contributes to the assessment of corrosivity in offshore atmospheric exposure environments according to DIN EN ISO 9224 for unalloyed steel, zinc, copper and aluminium. Studies on corrosivity from an offshore wind turbine and a distribution platform in the North Sea are presented. The results show that the corrosivity of unalloyed steel is mostly dependent on the altitude of exposure and whether it is inside or outside. T2 - Conference EUROCORR 2025 CY - Stavanger, Norway DA - 07.09.2025 KW - Weathnering Campaigns KW - North Sea KW - Corrosivity KW - Corrosion KW - Atmospheric Corrosion KW - Mass Loss KW - Corrosion Rate KW - Offshore Wind Turbine PY - 2025 AN - OPUS4-64086 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Burkert, Andreas T1 - Wasserstoffinduzierte Spannungsrisskorrosion an Spannstählen am Beispiel der Carolabrücke N2 - Ausgehend von grundlegenden Betrachtungen zur wasserstoffinduzierten Spannungsrisskorrosion und historischen Schadensfällen, werden am Beispiel der Carolabrücke die werkstoff- und medienseitigen sowie die konstruktiven Einflussgrößen auf den Schadensmechanismus erläutert. Aufbauend auf den vorliegenden Erkenntnissen werden weitergehende Maßnahmen zur zukünftigen Bewertung von Spannstahlbrücken abgeleitet. T2 - Technische Schulung „Fügeverfahren für ingenieurtechnisches Personal“ CY - Cottbus, Germany DA - 11.09.2025 KW - Spannstahl KW - Spannungsrisskorrosion KW - Wasserstoffversprödung PY - 2025 AN - OPUS4-64100 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Seifert, Lando T1 - A New Young Network - die junge gfkorr (Das Netzwerk für junge Korrosionisten) N2 - This invited talk at the Young EFC Meeting (European Federation of Corrosion) was about the new network, founded in Germany in 2023, specialising in corrosion and corrosion protection. The network is called "die junge gfkorr" and has the following aims: (i) Initiation of in-person events with excursions and a networking atmosphere. (ii) Members come from both industry and academia can find similarities in each other's work (iii) Get to know each other and learn from each other, and (iv) Members benefit long-term by using the network throughout their careers and for future collaboration on daily business and research projects. T2 - Conference EUROCORR 2025, Young EFC Meeting CY - Stavanger, Norway DA - 07.09.2025 KW - Coatings KW - Corrosion KW - Corrosion Protection KW - Network PY - 2025 AN - OPUS4-64102 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Dudziak, Mateusz A1 - Dural, Esra A1 - Dey, R. A1 - Ullrich, M. S. A1 - Huth, Christian A1 - Thomson, C. A1 - Schartel, Bernhard T1 - Together We Can: Synergistic Flame Retardancy by Melamine Polyphosphate and Phosphorylated Microalgae in Polylactide Biocomposites N2 - A strategy for enhancing the sustainable flame retardancy of polylactide (PLA) composites by partially replacing melamine polyphosphate (MPP), a commercial flame retardant proposed for PLA, with wastewater polyphosphate-enriched microalgae (P-Algae) has been explored. The incorporation of P-Algae at a 1:1 ratio with MPP leads to a notable synergistic effect, surpassing the expected additive behavior of the individual components. Comprehensive characterization encompassing thermogravimetric analysis coupled with FTIR, pyrolysis combustion flow calorimeter (PCFC), cone calorimeter, oxygen index (LOI), UL-94 tests, and rheological measurements—demonstrates that the presence of this biomaterial can significantly enhance flame retardant performance. Replacing 50% of MPP with P-Algae in PLA resulted in a 17% reduction in peak heat release rate (pHRR) and maintained a V-0 rating in UL-94 testing. The use of P-Algae does not compromise the flame retardancy of PLA but rather contributes positively, offering a promising path toward more sustainable flame-retardant systems. By leveraging naturally derived biomass, this approach aligns with the growing demand for novel eco-friendly technologies in polymer engineering. Insights into an innovative renewable additive as a functional and effective component in flame-retardant biocomposites have been achieved. KW - Flame retardancy KW - Melamine polyphosphate KW - Phosphorus- enriched microalgae KW - Polylactide PLA KW - Synergism PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-640539 DO - https://doi.org/10.1002/pat.70350 SN - 1099-1581 SN - 1042-7147 VL - 36 IS - 9 SP - e70350 PB - John Wiley & Sons Ltd. AN - OPUS4-64053 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schultz, C. A1 - Cunningham, Patrick A1 - Fan, J. A1 - Miller, S.A. T1 - Balancing the Mechanical Performance and Environmental Sustainability of Fiber-Reinforced Concrete N2 - Fiber-reinforced concrete (FRC) can have improved durability and tensile properties, potentially enabling the more efficient use of concrete and lowering greenhouse gas (GHG) emissions. Yet, systematic quantifications of the environmental impacts of FRC, particularly when paired with changes to mechanical properties and the implications for material longevity, are limited. Herein, an assessment following the life-cycle assessment methodology for four common FRCs was performed, namely, those reinforced with polyvinyl alcohol (PVA), steel (ST), polypropylene (PP), and polyethylene terephthalate (PET). The analysis was bound to a cradle-to-gate scope, and solely virgin fiber material production was considered for the environmental impacts. Coupled changes in compressive and tensile strength, environmental impacts, and the role of material longevity and cost relative to unreinforced concrete were examined. Findings from this work show that, similar to unreinforced concrete, cement remains a key source of GHG emissions in FRC production. However, in FRCs fibers can drive additional emissions by up to 55%. Notably, PVA and ST led to the highest impacts and costs, which were minimal for inclusions of PP and PET. Yet ST contributed to the greatest benefits in flexural and compressive strengths. When the effects of longevity were integrated, FRC with PP reinforcement could offer desired emissions reductions with minimal increase in use period and cost, but the other fiber reinforcements considered may need to offer longer service life extension to reduce emissions compared with conventional concrete. These results indicate that FRC can enhance mechanical performance, but fiber type selections should be informed by the design life to achieve actual GHG emissions reductions. KW - Fiber-reinforced concrete KW - Greenhouse gas emissions KW - Concrete KW - Cement KW - Durability PY - 2025 DO - https://doi.org/10.1061/JMCEE7.MTENG-19454 SN - 0899-1561 VL - 37 IS - 7 SP - 04025178-1 EP - 04025178-11 PB - American Society of Civil Engineers (ASCE) CY - Reston, VA AN - OPUS4-62987 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Seifert, Lando A1 - Müller, Thoralf A1 - Ebell, Gino T1 - The Influence of Hydrogen Loading and Prestressing on the Sensitivity of Prestressing Steel to Stress Corrosion Cracking N2 - This talk addresses the issue of hydrogen-induced stress corrosion cracking (HiSCC) in prestressing steels. The susceptibility to HiSCC is evaluated using free corrosion tests according to ISO 15630-3, which is problematic as it produces unreliable results. However, a new test method shows promising reproducible results and reveals that Cr-alloyed quenched and tempered (Q&T) steels are as sensitive to HiSCC as unalloyed Q&T steels. T2 - Conference EUROCORR 2025 CY - Stavanger, Norway DA - 07.09.2025 KW - Bridges KW - Stress Corrosion Cracking KW - Hydrogen-induced Stress Corrosion Cracking KW - Prestressing steels PY - 2025 AN - OPUS4-64087 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Baeßler, Matthias T1 - Anwendungsszenarien und Referenzanwendungen sensorbasiertes Monitoring N2 - Präsentiert wird eine Kategorisierung von Anwendungsszenarien für sensorbasiertes Monitoring und die Planung für die Referenzbauwerke mit SHM-Anwendungen. Im Rahmen des Forschungsvorhabens Aistec Pro werden Anwendungsszenarien für sensorbasiertes Monitoring kategorisiert und in Referenzanwendungen umgesetzt. Der Vortrag gibt einen Überblick über die abgeschlossene Planung. T2 - Jahrestreffen Verbund Aistec-Pro CY - Bonn, Germany DA - 17.09.2025 KW - SHM KW - Monitoring KW - Brückensicherheit KW - Aistec Pro PY - 2025 AN - OPUS4-64124 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kossatz, Philipp A1 - Mezhov, Alexander A1 - Andresen, Elina A1 - Prinz, Carsten A1 - Schmidt, Wolfram A1 - Resch-Genger, Ute T1 - Assessing the Applicability of Lanthanide-Based Upconverting Nanoparticles for Optically Monitoring Cement Hydration and Tagging Building Materials N2 - Chemically stable, lanthanide-based photon upconversion micro- and nanoparticles (UCNPs) with their characteristic multicolor emission bands in the ultraviolet (UV), visible (vis), near-infrared (NIR), and short-wave infrared (SWIR) arepromising optical reporters and barcoding tags. To assess the applicability of UCNPs for the monitoring of early stage cement hydration processes and as authentication tags for cementitious materials, we screened the evolution of the luminescence of Selfmade core-only NaYF4:Yb,Er UCNPs and commercial μm-sized Y2O2S:Yb,Er particles during the first stages of cement hydration, which largely determines the future properties of the hardened material. Parameters explored from the UCNP side included particle size, morphology, surface chemistry or coating, luminescence properties, and concentration in different cement mixtures. From the cement side, the influence of the mineral composition of the cement matrix was representatively examined for ordinary Portland cement (OPC) and its constituents tricalcium aluminate (C3A), tricalcium silicate (C3S), and gypsum at different water to cement ratios. Based on reflection and luminescence measurements, enabling online monitoring, which were complemented by XRD and isothermal heat-flow calorimetric measurements to determine whether the incorporation of these particles could impair cement hydration processes, well suited lanthanide particle reporters could be identified as well as application conditions. In addition, thereby the reporter influence on cement hydration kinetics could be minimized while still preserving a high level of information content. The best performance for the luminescence probing of changes during early stage cement hydration processes was observed for 25 nm-sized oleate (OA)-coated UCNPs added in a concentration of 0.1 wt %. Higher UCNP amounts of 1.0 wt % delayed cement hydration processes size- and surface coatingspecifically in the first 24 h. Subsequent luminescence stability screening studies performed over a period of about one year support the applicability of UCNPs as optical authentication tags for construction materials. KW - Quality assurance KW - Fluorescence KW - Nano KW - Particle KW - Synthesis KW - Quantum yield KW - NIR KW - Mechanism KW - Characterization KW - XRD KW - Calorimetry KW - Advanced material KW - Cement KW - Monitoring KW - Surface KW - Size KW - Lifetime KW - Barcode KW - Lanthanide KW - Upconversion KW - Encoding KW - Method PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-638318 DO - https://doi.org/10.1021/acsomega.5c02236 SN - 2470-1343 SP - 1 EP - 13 PB - ACS Publications AN - OPUS4-63831 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Strobl, Dominic A1 - Unger, Jörg F. A1 - Ghnatios, C. A1 - Klawoon, Alexander A1 - Pittner, Andreas A1 - Rethmeier, Michael A1 - Robens-Radermacher, Annika T1 - Efficient bead-on-plate weld model for parameter estimation towards effective wire arc additive manufacturing simulation N2 - Despite the advances in hardware and software techniques, standard numerical methods fail in providing real-time simulations, especially for complex processes such as additive manufacturing applications. A real-time simulation enables process control through the combination of process monitoring and automated feedback, which increases the flexibility and quality of a process. Typically, before producing a whole additive manufacturing structure, a simplified experiment in the form of a beadon-plate experiment is performed to get a first insight into the process and to set parameters suitably. In this work, a reduced order model for the transient thermal problem of the bead-on-plate weld simulation is developed, allowing an efficient model calibration and control of the process. The proposed approach applies the proper generalized decomposition (PGD) method, a popular model order reduction technique, to decrease the computational effort of each model evaluation required multiple times in parameter estimation, control, and optimization. The welding torch is modeled by a moving heat source, which leads to difficulties separating space and time, a key ingredient in PGD simulations. A novel approach for separating space and time is applied and extended to 3D problems allowing the derivation of an efficient separated representation of the temperature. The results are verified against a standard finite element model showing excellent agreement. The reduced order model is also leveraged in a Bayesian model parameter estimation setup, speeding up calibrations and ultimately leading to an optimized real-time simulation approach for welding experiment using synthetic as well as real measurement data. KW - Proper generalized decomposition KW - Model order reduction KW - Hardly separable problem KW - Additive manufacturing KW - Model calibration KW - Wire arc additive manufacturing PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-596502 DO - https://doi.org/10.1007/s40194-024-01700-0 SN - 0043-2288 SP - 1 EP - 18 PB - Springer AN - OPUS4-59650 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Feistkorn, S. A1 - Algernon, D. A1 - Arndt, R. A1 - Ebell, Gino A1 - Friese, M. A1 - Grosse, C. U. A1 - Holstein, R. A1 - Niederleithinger, Ernst A1 - Schickert, M. A1 - Schulze, S. A1 - Taffe, A. A1 - Walther, A. A1 - Wolf, J. A1 - Zoega, A. A1 - Zwanzig, M. T1 - Introduction to DIN 4871: Qualification of NDT Personnel in Civil Engineering (NDT-CE) N2 - Recently, non-destructive testing in civil engineering (NDT-CE), in particular of concrete components, has successfully mastered the leap from research to practice. Several methods have been established for field inspections to determine the concrete cover of reinforcement or to estimate the compressive strength as well as other parameters related to the concrete material. In addition, the application of nondestructive testing is indispensable, if information about the inner structure - such as the location of rebars and tendon ducts or the damage-related condition assessment to detect grouting defects, honeycombs, delamination, or corrosion - is required. Besides the selection of a suitable NDT method and an appropriate inspection system, the reliability of the results depends largely on the person who applies the non-destructive inspection technique and evaluates the inspection results. To ensure a high quality of non-destructive concrete evaluation as well as to keep the uncertainty caused by the inspection personnel to a minimum, structured, consistent and regulated theoretical as well as practical training of inspection personnel is essential. To close this gap, the subcommittee of education (UA-A) within the committee for NDT-CE of the German Society for Nondestructive Testing (DGZfP) has been reactivated in 2018 to establish uniform training standards for nondestructive concrete inspections in the long term. The subcommittee consists of scientists, practitioners, authorities, and clients. So far, the national standard DIN 4871 “Non-destructive testing - Qualification and Certification of NDT personnel in Civil Engineering (NDT-CE)” was developed and is currently under review. This standard considers the civil-industry-specifics, for example, that standards for NDT of concrete, as well as related product standards with a few exceptions, still do not exist at the moment. Within this presentation, the concept, the connection to ISO 9712 and other standards as well as an overview of the developed German standard DIN 4871 will be presented. T2 - NDT-CE 2022 CY - Zurich, Switzerland DA - 16.08.2022 KW - Non-destrucive testing KW - Civil engineering PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-555250 UR - https://www.ndt.net/article/ndtce2022/paper/66594_manuscript.pdf VL - 2022/09 SP - 1 EP - 12 PB - NDT.net CY - Bad Breisig AN - OPUS4-55525 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Lay, Vera A1 - Baensch, Franziska A1 - Skłodowska, Anna A1 - Fritsch, Tobias A1 - Stamm, Michael A1 - Prabhakara, Prathik A1 - Johann, Sergej A1 - Sturm, Patrick A1 - Kühne, Hans-Carsten A1 - Niederleithinger, Ernst T1 - Multi–sensory Monitoring and Non–destructive Testing of New Materials for Concrete Engineered Barrier Systems N2 - The crucial part of nuclear waste storage is the construction of sealing structures made of reliable, safe and well–understood materials. We present an extended analysis of long-term multi–sensory monitoring and non–destructive testing (NDT) inspection of two laboratory specimens aiming at potential materials for sealing structures for nuclear waste repositories. Specimens with a volume of 340 litres made from newly developed alkali–activated materials (AAM) and established salt concrete (SC) were analysed using embedded acoustic emission and wireless radio-frequency identification (RFID) sensors, ultrasonic echo imaging, active thermography, and X–ray computed tomography. The monitoring analysis showed lower heat of reaction and 50% less acoustic emission events in AAM compared to SC. However, due to the surface effects of the AAM material, the number of acoustic emission events increased significantly after approximately two months of monitoring. Subsequently performed NDT inspections reliably located embedded sensors and confirmed the absence of major cracks or impurities. The presented laboratory results show the feasibility and potential of comprehensive NDT monitoring and inspection to characterise cementitious and alternative materials as well as the need for multi–parameter long–term monitoring. Thus, our study demonstrates that tailored NDT investigations will help to develop safe sealing structures for nuclear waste repositories. KW - Radioactive waste KW - Barrier KW - Concrete KW - AAM KW - Non-destructive testing PY - 2024 DO - https://doi.org/10.3151/jact.22.516 SN - 1347-3913 VL - 22 IS - 9 SP - 516 EP - 529 PB - Japan Concrete Institute AN - OPUS4-61461 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Lay, Vera A1 - Mielentz, Frank A1 - Prabhakara, Prathik A1 - Baensch, Franziska A1 - Johann, Sergej A1 - Hofmann, Detlef A1 - Sturm, Patrick A1 - Stamm, Michael A1 - Niederleithinger, Ernst T1 - Multi-sensory monitoring and ultrasound for quality assurance at underground sealing structures N2 - Within the safety concepts of underground disposal sites of nuclear waste, engineered barriers play an important role. As these sealing structures have high demands concerning integrity, we aim at advancing the available construction materials, monitoring, and inspection techniques within the project SealWasteSafe. A specifically developed alkali-activated material is compared to classical salt concrete. A comprehensive multi-sensory monitoring scheme is used at 150-340 l specimens to monitor setting and hardening of both materials. All sensors are demonstrated to resist the highly alkaline environments. Besides cabled and wireless temperature and humidity of the materials, strain variations using fibre optic sensors and acoustic emissions are recorded over periods of at least 28 days, partly for more than eight months. After hardening of the specimens, further nondestructive evaluations using ultrasonic echo and thermographic measurements are conducted. Preliminary results proof the suitability of the tested sensors and clearly highlight differences between the tested materials. Particularly, the newly developed alkali-activated material shows lower acoustic emission activity indicating less cracking activity. Additionally, unique ultrasonic methods will enable better images of potential internal objects and cracks at in-situ sealing structures. A largescale ultrasonic system is optimised to reliably detect objects at a depth exceeding 9 m while still obtaining a good resolution. Modelling studies show the potential of further increasing the distance between individual transducer arrays. Additionally, a new ultrasonic borehole probe using phased arrays allowing for beam focussing is constructed and tested. Laboratory measurements at a halfcylindrical concrete specimen coincide well with the previous modelling. In total, the presented safe materials, detailed monitoring approaches and ultrasonic quality assurance methods will help to obtain safe sealing structures within salt as a host rock. The concepts can partly be transferred to sealing structures in alternative host rocks and will also be valuable for non-nuclear waste repositories. T2 - NDE NucCon CY - Espoo, Finland DA - 25.01.2023 KW - SealWasteSafe KW - Engineered barriers KW - Monitoring KW - Embedded sensors KW - Ultrasonic imaging PY - 2023 SP - 2 EP - 10 AN - OPUS4-56928 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Liao, Chun-Man A1 - Bernauer, F A1 - Niederleithinger, Ernst A1 - Igel, H A1 - Hadziioannou, C T1 - Assessment of prestress loss in a large-scale concrete bridge model under outdoor condition N2 - Environmental conditions affect the accuracy of field measurements used to monitor civil structures. Previous studies have shown that measured dynamic responses often lack the sensitivity needed for effective localized damage detection. To address this issue, our study focuses on distinguishing environmental effects from damage related effects in measured data to enhance vibration-based damage identification methods. Experimentally, the problem of prestress loss in a prestressed concrete bridge model was examined. By adjusting the pre-stressing force in a large-scale concrete bridge model, cracking phenomena were observed. To demonstrate field monitoring of a large-scale prestressed structure, noise recording was performed and the measurement data was analyzed with operational modal analysis. Additionally, ultrasonic testing, known for its high sensitivity in damage localization, was used to cross-check the structural damage. Seismic and coda wave interferometry were also employed to estimate wave velocities, providing insights into the level of prestress loss and temperature sensitivity. Ultimately, these measurable wave properties help to overcome the uncertainties associated with traditional vibration-based damage detection methods. T2 - EVACES 2025 CY - Porto, Portugal DA - 02.07.2025 KW - Prestress Loss KW - NDT KW - Ambient Vibration KW - Ultrasonic Testing KW - Coda Wave Interferometry KW - Seismic Interferometry PY - 2025 SN - 978-3-031-96105-2 DO - https://doi.org/10.1007/978-3-031-96106-9_20 VL - 2 SP - 181 EP - 189 PB - Springer Nature CY - Cham AN - OPUS4-64212 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Skłodowska, Anna A1 - Baensch, Franziska A1 - Lay, Vera A1 - Niederleithinger, Ernst A1 - Kühne, Hans-Carsten T1 - Acoustic emission monitoring for engineered barriers in nuclear waste disposal N2 - To safely dispose of nuclear waste in underground facilities, engineered barrier systems are needed to seal shafts and galleries. The material used in these barriers must be adapted to the host rock parameters. Shrinking and cracking must be avoided to provide a barrier with almost zero permeability. For repositories in salt rock environments, several types of salt concrete (SC) are possible construction materials. Within the project SealWasteSafe, we compared the behavior of an innovative alkali-activated material (AAM) with standard SC in their hydration and hardening phase. To monitor the microstructural changes within the two materials SC and AAM, acoustic emission (AE) signals have been recorded for up to ~250 days on 340-litercubic specimens. The phenomenon of AE is defined as the emission of elastic waves in materials due to the release of localized internal energy. Such energy release can be caused by the nucleation of micro-fracture, e.g., in concrete while curing or when exposed to load. The occurrence of AE events gives first rough indications of microstructural changes and potentially occurring cracking and thus, provides insights for structural health monitoring (SHM). The results show, that for the first 28 days after casting, less AE activity was detected in the AAM compared to SC. After 61 days, in the AAM material, the number of AE events exceeded those observed in the SC. However, the majority of the AE detected and located in AAM was related to surface effects, and not to microstructural changes or occurring cracks within the bulk volume. Additionally, the source location analysis indicated, that despite lower activity in SC, we observed some clustering of the events. In contrast, in AAM, the activity inside the specimen is randomly distributed over the whole volume. The monitoring results help to estimate the material’s sealing properties which are crucial to assess their applicability as sealing material for engineered barriers. T2 - 11th European Workshop on Structural Health Monitoring (EWSHM 2024) CY - Potsdam, Germany DA - 11.06.2024 KW - Endlager KW - Barriere KW - AAM KW - Akustische Emission PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-604699 UR - https://www.ndt.net/article/ewshm2024/papers/768_manuscript.pdf DO - https://doi.org/10.58286/29834 SN - 1435-4934 SP - 1 EP - 7 PB - NDT.net AN - OPUS4-60469 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Burkert, Andreas T1 - Neubewertung von metallenen Dach- und Fassadenmaterialien unter Dauerhaftigkeits- und Umweltaspekten N2 - Die Feldstudien haben gezeigt, dass die Dauer und Menge der Regenereignisse die Run-Off-Rate beeinflusst. Zwischen den Auslagerungsstandorten sind die Unterschiede gering. Bei Zink werden im ersten Jahr ca. 80 % der in Lösung gehenden Metallionen über den Run-OFF abgeschwemmt. Dagegen sind es bei Kupfer nur etwa 10 %. Grund ist die unterschiedliche Wasserlöslichkeit der gebildeten Korrosionsprodukte. Die Laborstudien haben gezeigt, dass der Einfluss von Regendauer und Regenmenge erwartungsgemäß hoch ist. Die Kombination aus geringer Dachneigung und einem pH-Wert von 4,5 führt zu den höchsten Run-Off-Raten für Zink und auch Kupfer. Zinkhydroxid-Korrosionsprodukte erhöhen die Run-Off-Rate, bis sich wasserunlösliche Zinkkarbonatschichten bilden. T2 - Sitzung DIN NA 062-01-71 AA Korrosion und Korrosionsschutz CY - Berlin, Germany DA - 16.10.2024 KW - Korrosion KW - Regensimulator KW - Runoff KW - Deckschichtbildung KW - Metalleintrag in die Umwelt PY - 2024 AN - OPUS4-61381 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Mensinger, M. A1 - Fischer, O. A1 - Oberhaidinger, F. A1 - Stimmelmayer, L. A1 - Ebell, Gino A1 - Babutzka, Martin T1 - Grouted joint for integral composite frame bridges suitable for hot dip galvanizing N2 - Due to the corrosion resistance of carbon steel, bridge constructions are currently protected against corrosion by applied coating systems. These coating systems need to be renewed after approximately 25 50 years. Galvanized constructions without any welding areas at the construction site could be prepared as grouted joints and can be used without any renewing for about 100 years. T2 - Intergalva 2022 CY - Rome, Italy DA - 20.06.2022 KW - Corrosion KW - Galvanized steel KW - Bridge PY - 2022 AN - OPUS4-55096 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bayerlein, Bernd A1 - Waitelonis, Jörg A1 - Birkholz, Henk A1 - Jung, Matthias A1 - Schilling, Markus A1 - v. Hartrott, Philipp A1 - Bruns, Marian A1 - Schaarschmidt, Jörg A1 - Beilke, Kristian A1 - Mutz, Marcel A1 - Nebel, Vincent A1 - Königer, Veit A1 - Beran, Lisa A1 - Kraus, Tobias A1 - Vyas, Akhilesh A1 - Vogt, Lars A1 - Blum, Moritz A1 - Ell, Basil A1 - Chen, Ya‐Fan A1 - Waurischk, Tina A1 - Thomas, Akhil A1 - Durmaz, Ali Riza A1 - Ben Hassine, Sahar A1 - Fresemann, Carina A1 - Dziwis, Gordian A1 - Beygi Nasrabadi, Hossein A1 - Hanke, Thomas A1 - Telong, Melissa A1 - Pirskawetz, Stephan A1 - Kamal, Mohamed A1 - Bjarsch, Thomas A1 - Pähler, Ursula A1 - Hofmann, Peter A1 - Leemhuis, Mena A1 - Özçep, Özgür L. A1 - Meyer, Lars‐Peter A1 - Skrotzki, Birgit A1 - Neugebauer, Jörg A1 - Wenzel, Wolfgang A1 - Sack, Harald A1 - Eberl, Chris A1 - Portella, Pedro Dolabella A1 - Hickel, Tilmann A1 - Mädler, Lutz A1 - Gumbsch, Peter T1 - Concepts for a Semantically Accessible Materials Data Space: Overview over Specific Implementations in Materials Science N2 - This article describes advancements in the ongoing digital transformation in materials science and engineering. It is driven by domain‐specific successes and the development of specialized digital data spaces. There is an evident and increasing need for standardization across various subdomains to support science data exchange across entities. The MaterialDigital Initiative, funded by the German Federal Ministry of Education and Research, takes on a key role in this context, fostering collaborative efforts to establish a unified materials data space. The implementation of digital workflows and Semantic Web technologies, such as ontologies and knowledge graphs, facilitates the semantic integration of heterogeneous data and tools at multiple scales. Central to this effort is the prototyping of a knowledge graph that employs application ontologies tailored to specific data domains, thereby enhancing semantic interoperability. The collaborative approach of the Initiative's community provides significant support infrastructure for understanding and implementing standardized data structures, enhancing the efficiency of data‐driven processes in materials development and discovery. Insights and methodologies developed via the MaterialDigital Initiative emphasize the transformative potential of ontology‐based approaches in materials science, paving the way toward simplified integration into a unified, consolidated data space of high value. KW - Semantic Interoperability KW - Data Spaces KW - Integration Workflows KW - MaterialDigital PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-622952 DO - https://doi.org/10.1002/adem.202401092 SN - 1527-2648 SP - 1 EP - 25 PB - Wiley-VCH CY - Weinheim AN - OPUS4-62295 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Lehmann, Jens T1 - Vorstellung Auslagerungsstandkonzept BAM N2 - Die BAM hat ein Design für Auslagerungsstände entwickelt, das mehrere Auslagerungsoptionen bietet. So können neben der herkömmlichen freibewitterten Auslagerung auch Prüfkörper in einem überdachten Bereich beprobt werden. Die Baupläne sind frei verfügbar und zielen auf eine einheitliche Gestaltung von Auslagerungsständen ab. In dem Vortrag wird das Konzept anhand von Bauzeichnungen und Grafiken vorgestellt. T2 - 3. Sitzung GfKORR Arbeitskreis “Atmosphärische Korrosion” CY - Online Meeting DA - 10.06.2024 KW - Korrosion KW - Experimente KW - Atmosphärische Korrosion KW - ISO 9223 KW - Auslagerung PY - 2024 AN - OPUS4-62080 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ebell, Gino T1 - Auslagerungsstand 41 Berlin N2 - Im Rahmen des UNESCO geförderten Materials Rise Projektes hat die BAM einen neuen Standort im Auftrag des Umweltbundesamtes erstellt. Hier werden Umweltdaten und Korrosionsparameer für verschiedene Werkstoffe ermittelt. Darüber hinaus werden BAM-eigene Proben zur Bestimmung der Korrosivität des Standortes ausgelagert. T2 - UBA-Rise Meeting 2024 CY - Online meeting DA - 16.10.2024 KW - Corrosion KW - Korrosion PY - 2024 AN - OPUS4-61370 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ebell, Gino T1 - Prestressed Concrete Structures with ConcentratedTendons- Structural Damage due to Hydrogen-Induced Stress Corrosin Cracking N2 - In the course of the deconstruction of the "Bridge of the 20th anniversary of the GDR" at the Altstädter Bahnhof in Brandenburg a. d. Havel, new information on the initiation of hydrogen-induced stress cracks was obtained. BAM was commissioned by the Brandenburg State Road Administration to participate in a corresponding joint project which is financed by the Federal Ministry for Digital and Transport. The added value of the new information gained in this project goes beyond the specific structure. It describes unexpected new damage patterns that can be transferred to other structures with concentrated tendons (tendon block method and Baur-Leonhardt method) and were previously unknown in this form. These should be made known to other developers to enable them to initiate any necessary actions. T2 - Consec 2024 CY - Chennai, India DA - 24.09.2024 KW - Corrosion KW - Spannstahl KW - Hydrogen KW - Korrosion PY - 2024 AN - OPUS4-61305 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Seifert, Lando T1 - Ziele der Jungen GfKORR N2 - Die Junge GfKORR soll ein attraktives Angebot für junge Leute sein, sich fachübergreifend zu vernetzen und einen Einstieg in Querschnittsthemen bieten. Sowohl der Korrosionsschutz zum Zwecke der Nachhaltigkeit und Sicherheit von Bauwerken als auch der Korrosionsschutz bei Energie- und Mobilitätssystemen soll in zukünftigen Veranstaltungen übergreifend betrachtet werden. Dabei wollen wir den fachlichen und informativen Input aus den Arbeitskreisen der GfKORR bei unseren Seminaren suchen. In diesem 1. Netzwerk- und Arbeitstreffen wurde die Fahrtrichtung der Jungen GfKORR genauer abgesteckt und es hat sich eine Leitungsebene gefunden. Weiter wollen wir ab 2024 interessante Präsenzveranstaltungen mit Exkursionen anbieten. T2 - 1. Netzwerk- und Arbeitstreffen Junge GfKORR CY - Berlin, Germany DA - 12.03.2024 KW - Junge GfKORR KW - Netzwerkbildung KW - Corrosion KW - Korrosion PY - 2024 AN - OPUS4-60990 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Seifert, Lando T1 - Review: Concrete Repair to EN 1504: Diagnosis, Design, Principles and Practice N2 - In 2019 CRC Press published the “Concrete Repair to EN 1504” as paperback. This issue does not differ in terms of content from the hardback publication of 2014. Like the previous version, the book covers both detailed background information on repair procedures of reinforced concrete structures and provides a reference work for technicians and people who are involved with the maintenance of these structures, according to EN 1504. The book presents a high number of figures and tables, i.e., approximately one illustration per page. For readers who prefer a more comfortable to handle paperback, the book is recommended; however, the hardback from 2014 is still up‐to‐date. KW - Corrosion KW - Concrete KW - Bridge PY - 2020 DO - https://doi.org/10.1002/maco.202070064 SN - 1521-4176 SN - 0947-5117 VL - 71 IS - 6 SP - 1036 PB - WILEY‐VCH Verlag GmbH & Co. KGaA CY - Weinheim AN - OPUS4-50838 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Farhat, Abbas A1 - Luu, Li-Hua A1 - Doghmane, Alexis A1 - Cuéllar, Pablo A1 - Benahmed, Nadia A1 - Wichtmann, Torsten A1 - Philippe, Pierre T1 - Micro and macro mechanical characterization of artificial cemented granular materials N2 - The focus of this study is the experimental characterization of cemented granular materials, with the aim of identifying the microscopic properties of the solid bonds and describing the extension to macroscopic mechanical strength of cemented samples.We chose to use artificially bonded granular materials, made of glass beads connected by solid paraffin bridges. The results of several sets of laboratory tests at different scales are presented and discussed. Micromechanical tests investigate the yield strength of single solid bonds between particles under traction, shearing, bending and torsion loading, as a function of variations in particle size, surface texture and binder content. Macro-scale tensile tests on cemented samples explore then the scale transition, including influence of confining walls through homothetic variations of the sample size. Despite the large statistical dispersion of the results, it was possible to derive and validate experimentally an analytical expression for micro tensile yield force as a function of the binder content, coordination number and grain diameter. In view of the data, an adhesive bond strength at the contact between bead and solid bond is deduced with very good accuracy and it is even reasonable to assume that the other threshold values (shear force, bending and torsion moments) are simply proportional to the tensile yield, thus providing a comprehensive 3D model of cemented bond. However, the considerable dispersion of the data at the sample scale prevents validation of the extended model for macroscopic yield stress. A final discussion examines the various factors that may explain intrinsic variability. By comparison with other more realistic systems studied in the literature in the context of bio-cementation, our artificial material nevertheless appears suitable for representing a cemented granular material. Being easy to implement, it could thus enable the calibration of discrete cohesion models for simulation of practical applications. KW - Cemented granular material KW - Micro-mechanical characterisation KW - Artificial soils KW - Yield tensile stress PY - 2024 DO - https://doi.org/10.1007/s10035-024-01426-2 SN - 1434-5021 VL - 26 IS - 3 SP - 1 EP - 20 PB - Springer CY - Berlin AN - OPUS4-63507 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kullolli, Borana T1 - Modelling and calibration for cyclic soil-structure interface behavior N2 - The structural performance of many geotechnical systems (e.g. axially-loaded pile foundations), depends on the shearing resistance at the soil interface, which may govern the load bearing capacity of the foundation. Experimental investigations have shown that this interaction is mainly localised within a narrow shear band next to the structure. Under cyclic loading, a contraction of the soil at the interface may arise (net volume loss), possibly leading to a stress relaxation and thus to a reduction of the load bearing capacity (the so-called friction fatigue). Based on the constitutive similarities between soil continua and interfaces, we propose here the adaption of a Generalized Plasticity model for sandy soils for the numerical analysis of interface problems. In this contribution, the results of an experimental campaign for the parameter calibration of the constitutive model are presented. The tests have been conducted with a ring shear device involving different normal stresses, roughness of the steel plates as well as cyclic loading. The new modelling approach shows promising results and has the additional practical advantage that the interface zone and the soil continuum can both be described with the same constitutive model in general boundary value problems. T2 - Konferenz :International Symposium of Geomaterials CY - Glasgow, Scotland, UK DA - 26.06.2019 KW - Offshore foundations KW - Soil-structure interaction PY - 2019 AN - OPUS4-48446 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bekemeier, Simon A1 - Caldeira Rêgo, C. R. A1 - Mai, H. L. A1 - Sikia, Ujjal A1 - Waseda, O. A1 - Apel, M. A1 - Arendt, F. A1 - Aschemann, A. A1 - Bayerlein, Bernd A1 - Courant, R. A1 - Dziwis, G. A1 - Fuchs, F. A1 - Giese, U. A1 - Junghanns, K. A1 - Kamal, M. A1 - Koschmieder, L. A1 - Leineweber, S. A1 - Luger, M. A1 - Lukas, M. A1 - Maas, J. A1 - Mertens, J. A1 - Mieller, Björn A1 - Overmeyer, L. A1 - Pirch, N. A1 - Reimann, J. A1 - Schröck, S. A1 - Schulze, P. A1 - Schuster, J. A1 - Seidel, A. A1 - Shchyglo, O. A1 - Sierka, M. A1 - Silze, F. A1 - Stier, S. A1 - Tegeler, M. A1 - Unger, Jörg F. A1 - Weber, M. A1 - Hickel, Tilmann A1 - Schaarschmidt, J. T1 - Advancing Digital Transformation in Material Science: The Role of Workflows Within the MaterialDigital Initiative N2 - The MaterialDigital initiative represents a major driver toward the digitalization of material science. Next to providing a prototypical infrastructure required for building a shared data space and working on semantic interoperability of data, a core focus area of the Platform MaterialDigital (PMD) is the utilization of workflows to encapsulate data processing and simulation steps in accordance with findable, accessible, interoperable, and reusable principles. In collaboration with the funded projects of the initiative, the workflow working group strives to establish shared standards, enhancing the interoperability and reusability of scientific data processing steps. Central to this effort is the Workflow Store, a pivotal tool for disseminating workflows with the community, facilitating the exchange and replication of scientific methodologies. This article discusses the inherent challenges of adapting workflow concepts, providing the perspective on developing and using workflows in the respective domain of the various funded projects. Additionally, it introduces the Workflow Store’s role within the initiative and outlines a future roadmap for the PMD workflow group, aiming to further refine and expand the role of scientific workflows as a means to advance digital transformation and foster collaborative research within material science. KW - Digitalisation KW - FAIR principles KW - MaterialDigital KW - Scientific workflows KW - Semantic interoperability PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-624088 DO - https://doi.org/10.1002/adem.202402149 SN - 1527-2648 IS - 2402149 SP - 1 EP - 25 PB - Wiley-VCH GmbH AN - OPUS4-62408 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kemmler, Samuel A1 - Rettinger, Christoph A1 - Rüde, Ulrich A1 - Cuéllar, Pablo A1 - Köstler, Harald T1 - Efficiency and scalability of fully-resolved fluid-particle simulations on heterogeneous CPU-GPU architectures N2 - Current supercomputers often have a heterogeneous architecture using both conventional Central Processing Units (CPUs) and Graphics Processing Units (GPUs). At the same time, numerical simulation tasks frequently involve multiphysics scenarios whose components run on different hardware due to multiple reasons, e.g., architectural requirements, pragmatism, etc. This leads naturally to a software design where different simulation modules are mapped to different subsystems of the heterogeneous architecture. We present a detailed performance analysis for such a hybrid four-way coupled simulation of a fully resolved particle-laden flow. The Eulerian representation of the flow utilizes GPUs, while the Lagrangian model for the particles runs on conventional CPUs. Two characteristic model situations involving dense and dilute particle systems are used as benchmark scenarios. First, a roofline model is employed to predict the node level performance and to show that the lattice-Boltzmann-based Eulerian fluid simulation reaches very good performance on a single GPU. Furthermore, the GPU-GPU communication for a large-scale Eulerian flow simulation results in only moderate slowdowns. This is due to the efficiency of the CUDA-aware MPI communication, combined with the use of communication hiding techniques. On 1024 A100 GPUs, an overall parallel efficiency of up to 71% is achieved. While the flow simulation has good performance characteristics, the integration of the stiff Lagrangian particle system requires frequent CPU-CPU communications that can become a bottleneck, especially when simulating the dense particle system. Additionally, special attention is paid to the CPU-GPU communication overhead since this is essential for coupling the particles to the flow simulation. However, thanks to our problem-aware co-partitioning, the CPU-GPU communication overhead is found to be negligible. As a lesson learned from this development, four criteria are postulated that a hybrid implementation must meet for the efficient use of heterogeneous supercomputers. KW - Discrete element method KW - Hybrid implementation KW - High-performance computing KW - Particulate flow KW - Lattice Boltzmann method PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-623958 DO - https://doi.org/10.1177/10943420241313385 SN - 1741-2846 SP - 1 EP - 19 PB - SAGE Publications AN - OPUS4-62395 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Zinas, Orestis A1 - Papaioannou, Iason A1 - Schneider, Ronald A1 - Cuéllar, Pablo T1 - Multivariate Gaussian Process Regression for 3D site characterization from CPT and categorical borehole data N2 - Accurate prediction of subsurface stratigraphy and geotechnical properties, along with quantification of associated uncertainties, is essential for improving the design and assessment of geotechnical structures. Several studies have utilized indirect data from Cone Penetration Tests (CPTs) and employed statistical and Machine Learning methods to quantify the geological and geotechnical uncertainty. Incorporating direct borehole data can reduce uncertainties. This study proposes a computationally efficient multivariate Gaussian Process model that utilizes site-specific data and: (i) jointly models multiple categorical (USCS labels) and continuous CPT variables, (ii) learns a non-separable covariance structure leveraging the Linear Model of Coregionalization, and (iii) predicts a USCS based stratigraphy and CPT parameters at any location within the 3D domain. The results demonstrate that integrating geotechnical and geological data into a unified model yields more reliable predictions of subsurface stratification, enabling the parallel interpretation of both USCS classification and CPT profiles. Importantly, the model demonstrates its potential to integrate multiple variables from different sources and data types, contributing to the advancement of methodologies for the joint modeling of geotechnical, geological, and geophysical data. KW - Geotechnical site-characterization KW - Cone Penetration Tests KW - Stratigraphy prediction KW - Multivariate Gaussian process KW - Variational inference KW - Linear Model of Coregionalization PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-629456 DO - https://doi.org/10.1016/j.enggeo.2025.108052 SN - 1872-6917 VL - 352 SP - 1 EP - 19 PB - Elsevier B.V. AN - OPUS4-62945 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Burkert, Andreas T1 - Neubewertung von metallenen Dach- und Fassadenmaterialien unter Dauerhaftigkeits- und Umweltaspekten N2 - Metallene Dach- und Fassadenmaterialien unterliegen nach ihrer Installation infolge von Korrosions- und Abschwemmprozessen einem Abtrag von Metallionen. Durch Regenereignisse gelangen diese in umliegende Gewässer und Böden. Die verwendeten metallenen Werkstoffe, wie z.B. Kupfer und Zink bilden zeitabhängig schützende Deckschichten aus, die die Dauerhaftigkeit der Werkstoffe gewährleisten und damit den Austrag von Metallionen signifikant begrenzen. Die Geschwindigkeit der Deckschichtbildung sowie die erreichte Schutzwirkung sind von verschiedenen Umwelteinflüssen und klimatischen Bedingungen abhängig. Diese haben sich in den letzten Jahrzehnten in Europa stark verändert, so dass es einer aktuellen Datenbasis für die Bewertung der Dauerhaftigkeit und der Umweltauswirkungen bedarf. Im Rahmen eines Forschungsvorhabens werden aktuell Feldstudien zur Ermittlung des Runoffs und der Schutzwirkung der gebildeten Deckschichten durchgeführt. Ergänzt werden diese durch Laborversuche mit künstlicher Beregnung. T2 - 76. Sitzung DIN Arbeitsausschuss Korrosion und Korrosionsschutz CY - Berlin, Germany DA - 17.10.2023 KW - Atmosphärische Korrosion KW - Runoff KW - Deckschichtbildung KW - Schutzwirkung KW - Umgebungseinflüsse PY - 2023 AN - OPUS4-58706 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Spilker, Alexandra A1 - Recknagel, Christoph A1 - Kuban, Andre A1 - Alte-Teigeler, Tim ED - Spilker, Aleandra T1 - Visuelle Erfassung und Bewertung von Fugensystemen in Verkehrsflächen aus Beton N2 - Fugensysteme sind planmäßige Erhaltungssysteme. Mit der vorliegenden Veröffentlichung werden reproduzierbare Kriterien und Bewertungsmaßstäbe zur vereinheitlichten Bewertung von Fugen und Fugenfüllsystemen bereit gestellt. Auf der Grundlage visuell detektierbarer Kriterien, die in praktikabler Weise im Feld gewonnen werden können, wird eine Handlungsgrundlage zur Sicherstellung funktionsfähiger Betonfahrbahnbeläge im Fugenbereich zur Verfügung gestell.t KW - Performance-Bewertung in situ KW - Hopchbeanspruchte Infratsruktur KW - Fahrbahnbeläge PY - 2025 SN - 978-3-86446-428-7 VL - 2025 SP - 3 EP - 24 PB - FGSV-Verlag CY - wesselinger Straße 15-17 in 50999 Köln ET - 1. Auflage AN - OPUS4-63229 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - von Werder, Julia T1 - Composite Facade Elements with Self-Cleaning Surface made of Ultra-High-Performance Concrete (UHPC) N2 - In the framework of the European project H-House various concrete façade elements were developed with the aim to ensure a long service life by combining a very durable material with self-cleaning properties. The façade elements presented are made of a shell of UHPC filled with blocks of aerated autoclaved concrete as insulating material. Self-cleaning properties were realized amongst others by imprinting a microstructure into the surface during casting. The paper focuses on selected technological aspects of the manufacturing process of prototypes which had to be performed in two concreting sections. Furthermore the challenges faced when upscaling the self-cleaning properties are addressed and the strategy to assess the self-cleaning properties by measuring the contact and the roll-off angel is presented. The results show that a successfull upscalaing process requires detailed planning and that the best results can often be achieved with a moderate work effort or material use. T2 - XV International Conference on Durability of Building Materials and Components (DBMC 2020) CY - Online meeting DA - 20.10.2020 KW - Ultra-High-Performance Concrete KW - Facade Elements KW - Self-Cleaning Properties KW - Adhesive Pull-Strength KW - Microstructure KW - Architectural Concrete PY - 2020 AN - OPUS4-51968 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Voigt, Marieke T1 - Thermally treated UHPC: a durability study N2 - Ultra high performance concrete (UHPC) is known for its high compressive strength of more than 150 MPa and its high durability. Thermal treatment at 90°C can accelerate the strength development so that the 28-days-strength can be achieved immediately after the treatment and an additional increase up to 30 % in some cases. The reason for the strength development is an accelerated hydration of the clinker minerals and an intensified pozzolanic reaction leading to a denser microstructure. In previous research inhomogeneities in form of a zonation after unprotected thermal treatment were observed and analysed in respect to changes in the microstructure. This zonation is defined by a different microstructure in the core compared to the outer zone in the matter of porosity, mineral phase composition and a significant change in the potassium and sulphur concentration of the zones is measurable. To isolate different transport mechanisms responsible for these element distributions UHPC samples were thermally treated at 90 °C and the microstructure was investigated under dry conditions and after immersion in water to investigate the influence of dehydration during and rehydration after the thermal treatment on the microstructure. Through durability testing via water absorption, water vapour diffusion, permeability testing and sulfuric acid resistance transport mechanisms like diffusion, migration, capillary suction are under investigation in correlation with the microstructure analysis. For the microstructure analysis measurements with µXRF, mercury intrusion porosity, XRD and SEM were conducted. T2 - HiPerMat 2020 CY - Kassel, Germany DA - 11.03.2020 KW - UHPC KW - Thermal treatment KW - Zonation KW - Transport mechanism KW - Durability PY - 2020 AN - OPUS4-52372 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Manninger, Tanja A1 - Rübner, Katrin A1 - von Werder, Julia T1 - Eco friendly stabilization of loam with calcined clay and potassium hydroxide: a new approach to improve water resistance N2 - Earth buildings and adobe construction have been in use for thousands of years. Loam is locally available, environmentally friendly and has a small CO2 footprint mainly resulting from extraction and transport. Because of these reasons loam is one of the building materials of the future. Water resistance is an important aspect when using loam as a construction material. If the structural option of building protruding roofs cannot be implemented, the water resistance of clay can be improved by stabilization. Positive properties of the material should not be diminished by stabilization. For example, the desired regulation of air humidity, which however cannot be fully preserved by cement stabilization. For an alternative and more appropriate stabilisation, different mixtures with calcined clays with alkali activator were examined. The calcination temperature for clays is usually lower than for cement and starts at 600° C. The calcined clays therefore also have a lower CO2 footprint compared to cement. To keep the mixture environmentally friendly potassium was used as alkali ion. It could be proven that the alkali activated polymer enhances water resistance of the loam mixture. Provided some further optimization the material shows potential to replace cement without compromising on the positive properties of clay. T2 - International Conference on Regeneration and Conservation of Structures (ICRCS 2022) CY - Kyoto, Japan DA - 07.09.2022 KW - Loam KW - Alkali activation PY - 2022 SP - 1 EP - 4 AN - OPUS4-56396 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Stuff, Maria T1 - GEMOSK - Entwicklung eines Schutzsystems zur Tuffsteinkonservierung N2 - Tuff ist in vielen historischen Objekten in Deutschland verbaut, hat aber wegen seiner Porosität und hygrischen Eigenschaften eine schlechte Verwitterungsresistenz. Ziel des Vorhabens ist die Entwicklung eines gesteinsmehlmodifizierten Schutzsystems auf Kieselsäurebasis (GEMOSK) zur Konservierung verbauter Tuffe. Für die Schutzmittelherstellung wird eine geeignete Mischung aus Kieselsol und feinen Gesteinsmehlen aus Steinbruchrückständen und Tuffabfällen verwendet. Bei erfolgreichem Abschluss des Projektes kann GEMOSK im Denkmalpflegebereich eingesetzt werden. Dadurch werden die Bausubstanz besser erhalten, Tuffsteinressourcen eingespart und Tuffabfälle wiederverwertet. T2 - Abteilungs-Vortragsseminar Abteilung 7 Bauwerkssicherheit CY - Berlin, Germany DA - 28.11.2019 KW - Denkmalpflege KW - Kieselsol KW - Tuff KW - Verwitterung PY - 2019 AN - OPUS4-50063 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Wachtendorf, Volker T1 - Gedanken, Tipps & Tricks zu künstlichen Bewitterungsprüfungen N2 - Die Fragestellung kann nur exemplarisch dargestellt werden, aber ist hoffentlich auch für langjährige Praktiker in den ausgewählten Punkten interessant. Es sollen für folgende Bereiche Beispiele gegeben werden: Probenvorbereitung, Testvorbereitung, Testdurchführung und Auswertung. T2 - 53. Jahrestagung der GUS 2025; Umwelteinflüsse erfassen, simulieren, bewerten. CY - Stutensee, Germany DA - 26.03.2025 KW - Künstliche Bewitterung KW - Umweltsimulation KW - Wechseltemperaturen KW - Prüfung KW - UV KW - Feuchte KW - Beregnung PY - 2025 AN - OPUS4-62862 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Nerger, Deborah T1 - Improved tomographic investigation for impact damage characterization N2 - Reinforced concrete (RC) is used as structural material in most diverse civil engineering applications. For the variability of its physical properties it is still an engineering challenge to meet all necessary requirements for the prediction of dynamic effects under impact loading. In this paper, investigations are shown within the scope of quantifying and evaluating the damage caused by an impact. The experimental investigations are performed in the field of low- and medium-velocity impact. The chosen flat nose shape results in small penetrations on the top side and scabbing on the bottom side. The plate is scanned with an adapted planar tomographic examination after the impact, and the damage is analysed, afterwards. Cracks and spalling are made visible with a reconstruction. The numerical model validated on the tomographic results justifies the application for further predictions of the damage description. T2 - 25th International Conference on Structural Mechanics in Reactor Technology - SMIRT25 CY - Charlotte, NC, USA DA - 04.08.2019 KW - Impact KW - Damage characterization KW - Planar tomography KW - Numeric simulation KW - Reinforced concrete structure PY - 2019 AN - OPUS4-49540 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Rappsilber, Tim A1 - Yusfi, Nawar A1 - Krüger, Simone A1 - Hahn, S.-K. A1 - Fellinger, Tim-Patrick A1 - Krug von Nidda, Jonas A1 - Tschirschwitz, Rico T1 - Meta-analysis of heat release and smoke gas emission during thermal runaway of lithium-ion batteries N2 - Herein a meta-analysis of 76 experimental research papers from 2000 to 2021 is given about possible effects on the thermal runaway of lithium-ion battery cells. Data on the hazards of gas emissions and released heat are related to each other and differentiated by cell properties such as, cell geometry, cathode type or state of charge. Quantitative information on the total heat release in the range of 2.0–112.0 kJ Wh−1, the peak heat release rate in the range of 0.006–2.8 kW Wh−1and the smoke gas emission were extracted, normalized in terms of cell energy (Wh), combined in a data library and compared graphically. The total amount of gas emitted (3–48 mmol Wh−1) as well as the released amount of carbon monoxide (1–161 mg Wh−1) and hydrogen fluoride (2–197 mg Wh−1) were investigated as a function of the state of charge and cell geometry. The analysis reveals that the measured values are significantly influenced by the types of calorimeters and smoke gas analyzers used as well as by the type of thermal runaway trigger. This meta-analysis can serve as an important basis for any risk assessment of lithium-ion batteries. KW - Lithium-ion battery KW - Thermal runaway KW - Cathode active material KW - Heat release KW - Smoke gas emission PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-568071 DO - https://doi.org/10.1016/j.est.2022.106579 SN - 2352-152X VL - 60 SP - 1 EP - 15 PB - Elsevier CY - Amsterdam AN - OPUS4-56807 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Herrmann, Ralf A1 - Schneider, Ronald A1 - Simon, Patrick A1 - Hille, Falk A1 - Said, Samir A1 - Baeßler, Matthias ED - Curbach, M. ED - Marx, S. ED - Scheerer, S. ED - Hampel, T. T1 - Structural Health Monitoring der Maintalbrücke Gemünden zur Unterstützung einer prädiktiven Instandhaltung N2 - Nach den bisherigen Regeln werden Bauwerksprüfungen von Brücken in starr definierten Intervallen durchgeführt. Diese starre, periodische, zustandsbasierte Instandhaltungsstrategie soll zukünftig durch eine flexible und prädiktive Instandhaltung ersetzt werden. Hierbei sollen Inspektionen und Instandhaltungsmaßnahmen unterstützt durch autonome Systeme auf der Grundlage von Monitoringdaten geplant und zusätzlich bei unvorhergesehenen Ereignissen ausgelöst werden. Im Rahmen des Verbundforschungsvorhabens AISTEC wird ein Vorgehen für Großbauwerke und kleinere Regelbauwerke zur Umsetzung eines kombinierten globalen, schwingungsbasierten und quasistatischen Monitorings entworfen. An der Maintalbrücke Gemünden – einer semiintegralen Rahmenbrücke aus Spannbeton auf der Schnellfahrstrecke Hannover–Würzburg – wurde als Demonstrator ein Dauermonitoring realisiert. T2 - 11. Symposium Experimentelle Untersuchungen von Baukonstruktionen (SEUB) CY - Online meeting DA - 08.03.2021 KW - Structural Health Monitoring KW - Umwelteinflüsse KW - Prädiktive Instandhaltung PY - 2021 UR - https://tu-dresden.de/bu/bauingenieurwesen/imb/ressourcen/dateien/veranstaltungen/seub/11-seub-2021/2021_SEUB11_06_Herrmann_et_al.pdf?lang=de VL - 55 SP - 66 EP - 76 PB - Technische Universität Dresden CY - Dresden AN - OPUS4-52810 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Diercks, Philipp A1 - Gläser, D. A1 - Unger, Jörg F. A1 - Crusoe, M. R. A1 - Huber, S. T1 - BAMresearch/NFDI4IngScientificWorkflowRequirements: Initial version N2 - Software-driven scientific workflows are often characterized by a complex interplay of various pieces of software executed in a particular order. The output of a computational step may serve as input to a subsequent computation, which requires them to be processed sequentially with a proper mapping of outputs to inputs. Other computations are independent of each other and can be executed in parallel. Thus, one of the main tasks of a workflow tool is a proper and efficient scheduling of the individual processing steps. Each processing step, just as the workflow itself, typically processes some input and produces output data. Apart from changing the input data to operate on, processing steps can usually be configured by a set of parameters to change their behavior. Moreover, the behavior of a processing step is determined by its source code and/or executable binaries/packages that are called within it. Beyond this, the computation environment not only has a significant influence on its behavior, but is also crucial in order for the processing step to work at all. The environment includes the versions of the interpreters or compilers, as well as all third-party libraries and packages that contribute to the computations carried out in a processing step. KW - Zenodo KW - 7790634 PY - 2023 DO - https://doi.org/10.5281/zenodo.7790633 PB - Zenodo CY - Geneva AN - OPUS4-59687 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Held, Felix T1 - Efficient model updating in structural analysis using proper generalized decomposition N2 - The proper generalized decomposition is combined with a Bayesian model updating to identify unknown material parameters for mechanical structures. A convergence analysis for the Bayesian updating procedure is finally presented. T2 - ECCOMAS YIC 2019 5th Young Investigators Conference CY - Krakau, Poland DA - 01.09.2019 KW - Efficient model updating KW - Structural analysis PY - 2019 AN - OPUS4-48902 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Viefhues, Eva A1 - Döhler, M. A1 - Zhang, Q. A1 - Hille, Falk A1 - Mevel, L. T1 - Subspace-based Damage Detection with Rejection of the Temperature Effect and Uncertainty in the Reference N2 - Temperature variation can be a nuisance that perturbs vibration based structural health monitoring (SHM) approaches for civil engineering structures. In this paper, temperature affected vibration data is evaluated within a stochastic damage detection framework, which relies on a null space based residual. Besides two existing temperature rejection approaches – building a reference state from an averaging method or a piecewise method – a new approach is proposed, using model interpolation. In this approach, a general reference model is obtained from data in the reference state at several known reference temperatures. Then, for a particular tested temperature, a local reference model is derived from the general reference model. Thus, a well fitting reference null space for the formulation of a residual is available when new data is tested for damage detection at an arbitrary temperature. Particular attention is paid to the computation of the residual covariance, taking into account the uncertainty related to the null space matrix estimate. This improves the test performance, contrary to prior methods, for local and global damages, resulting in a higher probability of detection (PoD) for the new interpolation approach compared to previous approaches. T2 - International Operational Modal Analysis Conference CY - Copenhagen, Danmark DA - 13.05.2019 KW - Uncertainty KW - Statistical method KW - Subspace-based method KW - Temperature rejection KW - Model interpolation PY - 2019 SP - 1 EP - 11 AN - OPUS4-48240 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bhuyan, Md Delwar Hossain A1 - Le Touz, N. A1 - Gautier, G. A1 - Döhler, M. A1 - Hille, Falk A1 - Dumoulin, J. A1 - Mevel, L. T1 - Load Vector Based Damage Localization with Rejection of the Temperature Effect N2 - The Stochastic Dynamic Damage Locating Vector (SDDLV) approach is a vibration-based damage localization method based on both a finite element model of a structure and modal parameters estimated from output-only measurements in the damage and reference states. A statistical version of the Approach takes into account the inherent uncertainty due to noisy measurement data. In this paper, the effect of temperature fluctuations on the performance of the method is analyzed in a model-based approach using a finite element model with temperature dependent parameters. Robust damage localization is carried out by rejecting the temperature influence on the identified modal parameters in the damaged state. The algorithm is illustrated on a simulated structure. T2 - International Operational Modal Analysis Conference CY - Copenhagen, Danmark DA - 13.05.2019 KW - Statistical evaluation KW - Damage localization KW - SDDLV KW - Load vector KW - Temperature rejection PY - 2019 SP - 1 EP - 10 AN - OPUS4-48241 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Baeßler, Matthias A1 - Haake, Gerrit T1 - ReNEW - Entscheidungstools für die Nutzungsverlängerung und das Repowering von Windenergieanlagen N2 - Der Vortrag gibt einen Überblick über gängige Nachnutzungskonzepte, die im Rahmen des Forschungsvorhabens ReNEW untersucht werden. Hierzu wir eine probabilistisches Entscheidungsmodell eingeführt. Die Möglichkeiten von Bauwerksertüchtigungen werden erörtert. T2 - RAVE ROWD Workshop 2024 CY - Hannover, Germany DA - 10.12.2024 KW - Windenergieanlagen KW - Bauwerksertüchtigung KW - Offshore-Windparks KW - Repowering PY - 2024 AN - OPUS4-62237 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Recknagel, Christoph A1 - Hoppe, Johannes A1 - Eilers, M. T1 - Technische Prüfvorschriften für die Dichtungsschicht aus einer Polymerbitumen-Schweißbahn zur Herstellung von Brückenbelägen auf Beton TL/TP-ING - Teil 7: Brückenbeläge, Abschnitt 1 N2 - Die "Technischen Prüfvorschriften für die Dichtungsschicht aus einer Polymerbitumen-Schweißbahn zur Herstellung von Brückenbelägen auf Beton" (TP BEL-B 1) enthalten alle notwendigen Angaben zur Durchführung der nach den "Technischen Lieferbedingungen für die Dichtungsschicht aus einer Polymerbitumen-Schweißbahn zur Herstellung von Brückenbelägen auf Beton" (TL BEL-B 1) geforderten Prüfungen. Art und Umfang der Einzelprüfungen sowie die entsprechenden Anforderungen sind den zugehörigen TL BEL-B 1 zu entnehmen. KW - Brückenbeläge KW - Asphaltbauweise KW - PmB Schweißbahn KW - Technische Anforderungen PY - 2022 SN - 978-3-86446-326-6 VL - 784/1 SP - 1 EP - 11 PB - FGSV Verlag GmbH CY - Köln AN - OPUS4-54857 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Geburtig, Anja T1 - Simulationsdaten zur photooxidativen Beanspruchung an verschiedenen geografischen Freibewitterungs-Standorten N2 - Freibewitterungen weisen grundsätzlich eine hohe Variabilität der jeweiligen Intensität der Beanspruchungsparameter auf; sie sind nicht einfach wiederholbar. Um dennoch die Ergebnisse einer Beanspruchung vergleichen zu können, ist eine aussagekräftige Charakterisierung der Freibewitterung wichtig. Traditionell werden Daten bekannter Einflussgrößen wie Globalstrahlung, Temperatur oder Feuchtewerte herangezogen. Obwohl man weiß, dass diese Größen an den exponierten Oberflächen wechselwirken und kombiniert als Mikroklima Einfluss auf Degradationsprozesse nehmen, werden schon aus Praktikabilitätsgründen diese separat als klimatische Messgrößen angegeben. Die Aussagekraft dieser Daten ist mäßig. Ziel dieses Beitrags ist es, die Aussagekraft und damit Vergleichbarkeit zu erhöhen, indem diese Messdaten als Stundendaten zu Wirkintegralen vorverarbeitet und jahresweise akkumuliert werden. Betrachtet wird dafür der Prozess der Photooxidation, da dieser Alterungs-mechanismus bei allen Kunststoffen auftritt. Für eine einfache Modellierung wird die wirksame UV-Bestrahlung, gewichtet mit einer Arrhenius-abhängigen Ober¬flächen-temperatur (TOF), über den Beanspruchungszeitraum von hier je einem Jahr akkumuliert. Die Idee einer solchen Messgröße für photooxidative Ober¬flächen¬alterung wurde bereits vorgestellt [1]. Dort wurde ein Gerät vor¬geschlagen, mit dem dieser Wert für verschieden absorbierende Oberflächen für die Dauer einer Exposition akkumuliert wird, und ergänzend eine Abschätzung der Betauungs¬zeiten dieser Referenz-Oberflächen erfolgen könnte. Hier soll es um eine rechnerisch generierte Zusammenstellung dieser photo¬oxidativen 1-Jahres-Alterungswerte für verschiedene Standorte gehen. Ein Temperaturfaktor erfasst dabei den Einfluss der Strahlungserwärmung auf eine weiße, graue bzw. schwarze Referenzoberflächen, spiegelt also die Kopplung von solarer Strahlung und Temperatur wider [1]. Ermittelt wird er aus Stunden¬daten der Globalstrahlung und der Lufttemperatur. Die spektrale Wirkung wird aus Sonnenhöhenständen entsprechend der geografischen Breite mit Hilfe der FastRT-Oberfläche [2] als PiT·h-Wert abgeschätzt [3]. Anhand der errechneten Jahreswerte können die Schweregrade der photo¬oxidativen Beanspruchung an den verschiedenen Standorten unmittelbar verglichen werden. Die gezeigten Simulationsdaten für ein solches „elektronisches Referenzmaterial“ für photooxidative Degradation zeigen die prinzipielle Möglichkeit einer Kartografierung solcher Daten auf. T2 - 53. Jahrestagung der GUS CY - Stutensee, Germany DA - 26.3.2025 KW - Polymer 3R KW - UV KW - Bestrahlung KW - Bewitterung PY - 2025 AN - OPUS4-62903 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Rai, Alena A1 - Stelzner, Ludwig A1 - Weise, Frank A1 - Wieland, M. T1 - 3D-Analyse von Betonfahrbahnoberflächen mit Grinding- und Groovingtextur mittels Streifenlichtprojektion N2 - Die Oberflächentexturierung der Betonfahrbahndecken mittels Grinding- und Grooving steht seit einigen Jahren im Mittelpunkt der Forschung und Entwicklung des Betonstraßenbaus in Deutschland. In den vergangenen Jahren wurden die vorteilhaften Oberflächenperformances derartiger Texturen wie z.B. Griffigkeit, Ebenheit, Lärmminderung in zahlreichen Forschungsprojekten umfassend untersucht und daraus die Technologie „Texturgrinding“ entwickelt. Im Kontext des gegenwärtig verfolgten ganzheitlichen performanceorientierten Ansatzes liegt der Fokus nun verstärkt auf der Analyse und Charakterisierung der Oberflächentopografie von Grinding- bzw. Groovingtexturen. Insbesondere gilt ein Hauptaugenmerk hierbei der zeitlichen Entwicklung der Oberflächentexturen in Abhängigkeit von äußeren Einwirkungen durch Klima und Verkehr. Dieser Beitrag zeigt, dass durch den Einsatz eines auf Streifenlichtprojektion basierenden Messsystems, eine hochaufgelöste dreidimensionale Erfassung der Oberflächentopografie verschiedenartiger Grinding- und Groovingtexturen möglich ist. Darauf aufbauend wurden messtechnische Voraussetzungen zur Gewährleistung reproduzierbarer Messungen geschaffen, die eine Dokumentation der zeitlichen Texturveränderungen infolge klimatischer Beanspruchung ermöglichen. Anschließend wurden Auswerteroutinen zur quantitativen und statistischen Charakterisierung der Oberflächentextur entwickelt und angewandt, um exemplarisch die Veränderungen der Oberflächentopografie infolge klimatischer Beanspruchung quantitativ abzubilden. KW - Betonfahrbahndecken KW - Grinding KW - Grooving KW - Oberflächentexturierung KW - Streifenlichtprojektion PY - 2020 DO - https://doi.org/10.1002/best.202000015 SP - 1 EP - 9 PB - Wilhelm Ernst & Sohn Verlag für Architektur und technische Wissenschaften GmbH & Co. KG CY - Berlin AN - OPUS4-51012 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Oesch, Tyler A1 - Weise, Frank A1 - Bruno, Giovanni T1 - Detection and Quantification of Cracking in Concrete Aggregate through Virtual Data Fusion of X-ray Computed Tomography Images N2 - In this work, which is part of a larger research program, a framework called “virtual data fusion“ was developed to provide an automated and consistent crack detection method that allows for the cross-comparison of results from large quantities of X-ray Computed Tomography (CT) data. A partial implementation of this method in a custom program was developed for use in research focused on crack quantification in Alkali-Silica Reaction (ASR)-sensitive concrete aggregates. During the CT image processing, a series of image analyses tailored for detecting specific, individual crack-like characteristics were completed. The results of these analyses were then “fused” in order to identify crack-like objects within the images with much higher accuracy than that yielded by any individual image analysis procedure. The results of this strategy demonstrated the success of the program in effectively identifying crack-like structures and quantifying characteristics, such as surface area and volume. The results demonstrated that the source of aggregate has a very significant impact on the amount of internal cracking, even when the mineralogical characteristics remain very similar. River gravels, for instance, were found to contain significantly higher levels of internal cracking than quarried stone aggregates of the same mineralogical type. KW - X-ray Computed Tomography (CT) KW - Alkali-Silica Reaction (ASR) KW - Crack Detection KW - Damage Quantification KW - ASR-Sensitive Aggregate PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-512170 DO - https://doi.org/10.3390/ma13183921 VL - 13 IS - 18 SP - Paper 3921 PB - MDPI CY - Basel, Switzerland AN - OPUS4-51217 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ebell, Gino T1 - Galvanic Anode systems in Concrete structures and their performance part 1 N2 - Corrosion of reinforcement is one of the major reasons in questioning the sturdiness of building structures. The application of cathodic protection techniques plays a big role in controlling the corrosion process to ensure a longer service life of building structures. This systematic study compares the efficiency and durability of various discrete galvanic zinc anode systems available in the current market using different criteria for measuring efficiencies such as potential measurements, electrolyte resistance measurements and several polarization methods to determine the polarizability of the anodes. Results to validate the performance of long-time exposure of discrete zinc anodes in the concrete medium are already shown in 2021. Now the results of analyzing the phase boundary between mortar and anodes by using 3D computer tomography are shown, as also the field application at large-scale specimens where the potential distribution and the current were investigated. T2 - Eurocorr 2023 CY - Brussels, Belgium DA - 27.08.2023 KW - Corrosion KW - Corrosion Protection PY - 2023 AN - OPUS4-58169 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ebell, Gino T1 - Potential Mapping at Concrete Structures N2 - Electrochemical potential mapping is a recognized technique for the localization of corroding reinforcing steels. Areas of corroding reinforcement steel can be located in a non-destructive manner by means of this procedure. Half‐cell potential measurements are used in order to detect chloride‐induced corrosion. However, it is not recommended in order to assess the risk of carbonation‐induced corrosion. For this purpose, determining the carbonation depth and the concrete cover appears more appropriate. The content of this specification exclusively refers to the application of mobile, local variable reference electrodes, which are only placed on the concrete surface while measuring. The technique distinguishes itself thereby from the range of corrosion monitoring systems with stationary installed reference electrodes and sensor systems, respectively, whereby it is possible to continuously track measurements within the area of the installed electrodes. However, these methods are not dealt with in this specification. T2 - NDT&E Workshop 2024 CY - Baruth/Mark, Germany DA - 03.07.2024 KW - Corrosion KW - Potential mapping PY - 2024 AN - OPUS4-60584 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - INPR A1 - Boschmann Käthler, C. A1 - Ebell, Gino A1 - Keßler, S. A1 - Schiegg, Y. A1 - Dauberschmidt, C. A1 - Angst, U. M. T1 - A comparison of methods to assess the resistance of reinforcing steel against chloride‐induced corrosion in concrete: Particular consideration of 12% chromium steel N2 - The critical chloride content C(crit) is an indicator for the corrosion resistance of reinforcing steels in concrete. In this article, several experimental methods for determining the critical chloride content C(crit) of mild and an alloyed (12% Cr) steel in cementitious materials are compared. The methods used include accelerated polarization tests and tests using more natural (unpolarized) conditions in which chloride ingress occurs by diffusion and capillary uptake. The advantages and disadvantages of the methods are discussed, in particular, with the objective of reaching a compromise between applicability to practice and feasibility in laboratory testing. KW - Chloride‐induced corrosion KW - Critical chloride content KW - Reinforced concrete KW - Testing methods PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-529751 DO - https://doi.org/10.1002/maco.202112609 SN - 1521-4176 SP - 1 EP - 20 PB - Wiley-VCH CY - Weinheim AN - OPUS4-52975 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Valet, Svenja A1 - Burkert, Andreas A1 - Ebell, Gino A1 - Babutzka, Martin T1 - Determination of the corrosion product layer resistance on zinc and electrolytically galvanized steel samples by using gel electrolytes N2 - Although zinc and zinc coatings have been widely used for corrosion protection for decades new zinc coatings are constantly being developed. Characterizing the corrosion protectiveness of these new coatings, however, should not be underestimated. While exposure tests are time intensive, cyclic tests can only be used for a very limited field of application. Thus, electrochemical measurements provide both an efficient and an effective alternative. Conventional aqueous bulk electrolytes influence the surface layers of a tested zinc coating and are therefore not reliable. Gel electrolytes, however, have evolved over the last few years, are minimally invasive and provide reliable results. This work describes experiments with gel electrolytes made of agar. Unlike previous work, it proposes a composition of gel electrolyte for minimally invasive description of the protective power of naturally formed oxide layers on zinc and zinc coatings. Therefore, as a first part, the gel electrolyte made of agar is verified as a method for zinc and zinc-coated samples. Afterwards, this paper introduces the corrosion product layer resistance RL as a promising parameter to evaluate the protective power of zinc coatings. Results are verified with EIS and FTIR measurements. An example on a representative zinc coating demonstrates the practical application. KW - Gel electrolytes KW - Agar KW - Zinc coatings KW - Atmospheric exposure KW - Corrosion PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-526053 DO - https://doi.org/10.1016/j.electacta.2021.138191 SN - 0013-4686 VL - 385 SP - 138191 PB - Elsevier Ltd. AN - OPUS4-52605 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Seyhan, E. A1 - Ebell, Gino A1 - Jimenez, D. A1 - Chavez, J. A1 - Sanchez Alvarez, G T1 - Evaluation of SACI performance on reinforced concrete structures N2 - Surface applied corrosion inhibitors (SACI) are widely used to mitigate corrosion process of steel reinforcement in concrete. But they remain controversial as to their effectiveness and the ability to compare materials from different manufacturers and technologies. They are applied onto the surface of hardened concrete and penetrate towards steel reinforcement. This paper discusses the corrosion inhibition performances of dual-phase surface applied corrosion inhibitor and the efficiency of the corrosion inhibitor is assessed by selected testing procedures in BAM laboratories. T2 - ACHE 2022 CY - Santander, Spain DA - 20.06.2022 KW - Corrosion KW - Inhibitor PY - 2022 AN - OPUS4-55095 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wilbig, Janka A1 - Borges de Oliveira, F. A1 - Obaton, A.-F. A1 - Schwentenwein, M. A1 - Rübner, Katrin A1 - Günster, Jens T1 - Defect detection in additively manufactured lattices N2 - This paper investigates fast and inexpensive measurement methods for defect detection in parts produced by Additive Manufacturing (AM) with special focus on lattice parts made of ceramics. By Lithography-based Ceramic Manufacturing, parts were built both without defects and with typical defects intentionally introduced. These defects were investigated and confirmed by industrial X-ray Computed Tomography. Alternative inexpensive methods were applied afterwards on the parts such as weighing, volume determination by Archimedes method and gas permeability measurement. The results showed, that defects resulting in around 20% of change in volume and mass could be separated from parts free of defects by determination of mass or volume. Minor defects were not detectable as they were in the range of process-related fluctuations. Permeability measurement did not allow to safely identify parts with defects. The measurement methods investigated can be easily integrated in AM process chains to support quality control. KW - Additive manufacturing KW - Quality assurance KW - Defect detection KW - Lattices KW - Ceramics PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-513547 DO - https://doi.org/10.1016/j.oceram.2020.100020 VL - 3 SP - 100020 PB - Elsevier Ltd. AN - OPUS4-51354 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bayerlein, Bernd A1 - Hanke, T. A1 - Muth, Thilo A1 - Riedel, Jens A1 - Schilling, Markus A1 - Schweizer, C. A1 - Skrotzki, Birgit A1 - Todor, A. A1 - Moreno Torres, Benjami A1 - Unger, Jörg F. A1 - Völker, Christoph A1 - Olbricht, Jürgen T1 - A Perspective on Digital Knowledge Representation in Materials Science and Engineering N2 - The amount of data generated worldwide is constantly increasing. These data come from a wide variety of sources and systems, are processed differently, have a multitude of formats, and are stored in an untraceable and unstructured manner, predominantly in natural language in data silos. This problem can be equally applied to the heterogeneous research data from materials science and engineering. In this domain, ways and solutions are increasingly being generated to smartly link material data together with their contextual information in a uniform and well-structured manner on platforms, thus making them discoverable, retrievable, and reusable for research and industry. Ontologies play a key role in this context. They enable the sustainable representation of expert knowledge and the semantically structured filling of databases with computer-processable data triples. In this perspective article, we present the project initiative Materials-open-Laboratory (Mat-o-Lab) that aims to provide a collaborative environment for domain experts to digitize their research results and processes and make them fit for data-driven materials research and development. The overarching challenge is to generate connection points to further link data from other domains to harness the promised potential of big materials data and harvest new knowledge. KW - Data infrastructures KW - Digital representations KW - Digital workflows KW - Knowledge graphs KW - Materials informatics KW - Ontologies KW - Vocabulary providers PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-546729 DO - https://doi.org/10.1002/adem.202101176 SN - 1438-1656 SP - 1 EP - 14 PB - Wiley-VCH GmbH CY - Weinheim AN - OPUS4-54672 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Salari, Farid A1 - Zocca, Andrea A1 - Bosetti, Paolo A1 - Hlaváček, Petr A1 - Italiano, Antonino A1 - Gobbin, Filippo A1 - Colombo, Paolo A1 - Kühne, Hans-Carsten A1 - Sglavo, Vincenzo M. T1 - Powder-bed 3D printing by selective activation of magnesium phosphate cement: Determining significant processing parameters and their effect on mechanical strength N2 - The present work addresses powder bed binder jetting additive manufacturing by selective magnesium phosphate cement activation. Despite the potential of this technology to aid the digitalization of the construction industry, the effect of processing parameters on the mechanical performance of printed materials has not yet been studied to generate a guideline for the further development of the technology. Statistical methodologies were used to screen the effect of four printing process parameters (printing speed, layer thickness, raster angle, and build direction on flexural and compressive strength). As the exploited technology works with constant fluid pressure, the physical interpretation of the effect of each factor can be considered taking into account the interactions between the binder materials in the powder bed. Analysis of variance (ANOVA) indicated that printing speed and layer thickness significantly affect mechanical performances. Furthermore, the layout of samples for the printing process is preferable to be parallel the printhead movement. An anisotropic behavior was observed, and the samples subjected to compressive forces parallel to the layer plane possessed lower strength values. This effect can be interpreted as a result of a weak area of low density in between layers, leading to a pronounced delamination under compression. Even though the strength of the printed material is not suitable for a structural concrete, it can be marginally improved by design of experiment and optimized for non-structural applications, such as for porous artificial stone. Design of experiment coupled with ANOVA methods can be used in the future to support the development of novel material mixtures, thus expanding the fields of application of this novel additive manufacturing technology. KW - Concrete 3D-printing KW - Particle-bed binder jetting KW - Design of experiment PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-601654 DO - https://doi.org/10.1016/j.oceram.2024.100609 VL - 18 SP - 1 EP - 11 PB - Elsevier B.V. AN - OPUS4-60165 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Eichner, Lukas A1 - Gerards-Wünsche, Paul A1 - Happel, Karina A1 - Weise, Sigurd A1 - Haake, Gerrit A1 - Sieber, Lars A1 - Flederer, Holger A1 - Schneider, Ronald A1 - Herrmann, Ralf A1 - Hille, Falk A1 - Baeßler, Matthias A1 - Huhn, Holger A1 - Küchler, Andreas T1 - Digitales Datenmanagement für die Instandhaltung von Offshore-Windparks T1 - Digital data management for maintenance in offshore wind farms N2 - Im Forschungsprojekt DiMoWind-Inspect wurde untersucht, welche Grundvoraussetzungen geschaffen werden müssen, um digitale Methoden für die Instandhaltung von Offshore-Windenergieanlagen einsetzen zu können. Daten aus allen Lebensphasen der Anlagen werden derzeit nur selten effizient dafür genutzt, um die sinnvollsten Instandhaltungsmaßnahmen am richtigen Ort, zum richtigen Zeitpunkt und mit den geringsten Kosten durchzuführen. Eine im Vorhaben entwickelte einheitliche Strukturierung der bisher häufig unstrukturierten Bau- und Instandhaltungsdaten ermöglicht ihre übergreifende, anwenderspezifische Verfügbarkeit. Hierfür werden Prinzipien des Referenzkennzeichnungssystems RDS-PP adaptiert. Es wird aufgezeigt, wie neben Bauteilen auch zusätzliche Informationen wie Instandhaltungsmaßnahmen oder Mängel strukturiert werden können. Dem Ansatz des Building Information Modeling folgend werden die Bauwerkskomponenten direkt mit den Informationen aus Inspektionen und weiteren Instandhaltungsmaßnahmen verknüpft. So können Informationen aus dem Betrieb über den Zustand der Struktur verarbeitet und für die maßgebenden Berechnungen und Nachweise zur Verfügung gestellt werden. Als Anwendungsfall wird ein zweistufiges Konzept vorgestellt, das zur Bewertung der Ermüdungslebensdauer eines korrosionsgeschädigten Konstruktionsdetails der Gründungsstruktur einer Offshore-Windenergieanlage mit Informationen aus der Instandhaltung eingesetzt wird. N2 - The DiMoWind-Inspect research project explored the essential requirements for implementing digital methods in the maintenance of offshore wind turbines. Currently, data from all stages of the turbines' lifecycles are underutilized, leading to suboptimal maintenance actions being taken in terms of location, timing, and cost. A consistent structuring of previously often unstructured construction and maintenance data developed in the project enables their cross-disciplinary, user-specific availability. To accomplish this, the principles of the Reference Designation System for Power Plants RDS-PP are applied. In this way, additional information, such as maintenance measures or defects, can be structured alongside components. The components of the structures are directly linked with information from inspections and other maintenance activities, following the Building Information Modeling approach. This allows for processing operational information about the condition of the structure and providing it for relevant calculations and assessments. As a use case, a two-stage concept is presented, utilizing maintenance information to assess the fatigue life of a corrosion-damaged structural detail in the support structure of an offshore wind turbine. KW - Building Information Modeling KW - Datenmanagement KW - Instandhaltung KW - Offshore-Windenergie KW - Referenzkennzeichnungssystem PY - 2024 DO - https://doi.org/10.1002/bate.202400026 VL - 101 IS - 10 SP - 558 EP - 567 PB - Ernst & Sohn CY - Berlin AN - OPUS4-60765 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Villani, P. A1 - Unger, Jörg F. A1 - Weiser, M. T1 - Adaptive Gaussian process regression for Bayesian inverse problems N2 - We introduce a novel adaptive Gaussian Process Regression (GPR) methodology for efficient construction of surrogate models for Bayesian inverse problems with expensive forward model evaluations. An adaptive design strategy focuses on optimizing both the positioning and simulation accuracy of training data in order to reduce the computational cost of simulating training data without compromising the fidelity of the posterior distributions of parameters. The method interleaves a goal-oriented active learning algorithm selecting evaluation points and tolerances based on the expected impact on the Kullback-Leibler divergence of surrogated and true posterior with a Markov Chain Monte Carlo sampling of the posterior. The performance benefit of the adaptive approach is demonstrated for two simple test problems. T2 - Algoritmy 2024 - Central-European Conference on Scientific Computing CY - Vysoké Tatry, Slovakia DA - 15.03.2024 KW - Gaussian process regression KW - Bayesian inverse problems KW - Surrogate models KW - Parameter identification KW - Active learning PY - 2024 SP - 1 EP - 10 PB - Slovak University of Technology CY - Bratislava AN - OPUS4-60738 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Weigel, Sandra T1 - Charakterisierung von bitumenhaltigen Bindemitteln mittels FTIR Spektroskopie N2 - Die Fourier-Transformations-Infrarotspektroskopie (FTIR-Spektroskopie) bietet eine herausragende Charakterisierungsmöglichkeit für Bitumen und bitumenhaltige Bindemittel. In Kombination mit multivariaten Analysemethoden und somit einem chemometrischen Ansatz erlaubt die FTIR-Charakterisierung Aussagen über verschiedene übergeordnete Eigenschaften, wie die Raffinerie, den Alterungszustand oder die Alterungsempfindlichkeit, eine Abschätzung verschiedener chemischer und physikalischer Kennwerte, wie z.B. den Asphaltengehalt, den Erweichungspunkt Ring und Kugel, die Nadelpenetration sowie den komplexen Schermodul und den Phasenwinkel sowie die Identifizierung verschiedener Additive wie Polymere oder Wachse. T2 - Anwenderseminar MATERIAL 2024 CY - Leipzig, Germany DA - 03.06.2024 KW - Bitumen KW - Charakterisierung KW - FA KW - LDA KW - FTIR KW - PLSR KW - Multivariate Analysemethoden PY - 2024 AN - OPUS4-60741 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hothan, Sascha T1 - Forschungsprojekt "INSIST" N2 - Der Vortrag zeigt den Bearbeitungsstand des Forschungsvorhabens "Entwicklung eines Verfahrens zur in situ Bewertung des Feuerwiderstands von bestehenden Stahlkonstruktionen mit reaktiven Brandschutzsystem (RBS)" (INSIST). Die Entwicklung und der Bau eines Geräteprototyps wurden vorgenommen und ein Konzept zur Kalibration erarbeitet. Die bisherigen Untersuchungen belegen, dass das Verfahren Ergebnisse liefert, die denen konventioneller Brandversuche im untersuchten Parameterbereich gleichwertig sind. T2 - Sachverständigenausschuss Reaktive Baustoffe und Beschichtungen -B- (463a) des Deutschen Institutes für Bautechnik CY - Berlin, Germany DA - 13.02.2024 KW - INSIST KW - In situ Bewertung KW - RBS PY - 2024 AN - OPUS4-60777 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Meng, Birgit T1 - Wissensbasierte Digitalisierung von betontechnologischen Materialdaten N2 - Die sprunghaft zunehmende Wichtigkeit von FAIR- und Open-Data für die Qualitätssicherung, aber auch für die Nachnutzbarkeit von Daten und den Erkenntnisfortschritt führt zu enormem Flandlungsbedarf in Forschung und Entwicklung. Damit verbunden laufen derzeit vielfältige, ambitionierte Aktionen, z. B. bezüglich der Erstellung von Ontologien und Wissensgraphen. Das Knowhow entwickelt sich rasant, die Ansätze zur Implementation entstehen in verschiedenen Fachwelten bzw. mit unterschiedlichen Zielsetzungen parallel, so dass recht heterogene Herangehensweisen resultieren. Diese Veröffentlichung fokussiert auf Arbeiten, die derzeit als möglichst ganzheitlicher Ansatz für Materialdaten im Rahmen der Digitalisierungsinitiative „Plattform MaterialDigital" vorangetrieben werden. Die Autoren bearbeiten baustoffbezogene Aspekte im Verbundprojekt „LeBeDigital - Lebenszyklus von Beton". Zielsetzung ist die digitale Beschreibung des Materialverhaltens von Beton über den kompletten Herstellungsprozess eines Fertigteils mit einer Integration von Daten und Modellen innerhalb eines Workflows zur probabilistischen Material- und Prozessoptimierung. Es wird über die Vorgehensweise und die dabei gewonnenen Erfahrungen berichtet, nicht ohne den Blick auf die oft unterschätzte Komplexität der Thematik zu lenken. T2 - Ibausil 2023 CY - Weimar, Germany DA - 13.09.2023 KW - Beton KW - Digitalisierung KW - Datenmanagement KW - FAIR-Prinzip KW - Metadaten KW - Ontologie KW - Wissensgraph PY - 2023 AN - OPUS4-60964 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Strangfeld, Christoph T1 - Moisture diffusion affected by the Knudsen effect in temporal changing pore networks N2 - Almost all building materials in civil engineering have an open porosity and interact with or are affected by the environmental conditions. Structures might suffer from effects such as moisture adsorption, carbonation, corrosion, penetration of salt ions and chemical substances, etc. In the hygroscopic range, these processes are mostly driven by diffusion. Due to the confinement of small pores ( 1 m), the Knudsen effect reduces the molecular diffusion. This reduction can become more significant in case of temporal changing pore systems because of physisorption of water vapor, carbonation, or chemisorption. In this study, unstabilised earth blocks and earth masonry are investigated. In a first step, the pore size distribution of the blocks is measured and sorption isotherms are recorded in experiments. Besides the ordinary physisorption, the involved clay minerals undergo swelling or shrinking due to chemisorption. The following two effects must be considered: first, the reduction of the available pore space by the adsorbed water layer. For this, the Hillerborg sorption theory is used, which is a combination of the well-known Brunauer-Emmett-Teller sorption theory and the Kelvin equation. This allows the computation of adsorbed water layers even in curved pore geometries. Second, the variation of the initial pore size distribution due to chemisorption needs to be modelled. Based on these two models, the effective diffusion coefficient can be predicted. For validation, arrays of relative humidity sensors were embedded into a free-standing earth masonry wall. This monitoring was carried out over more than a year to have a broad variety of environmental conditions and was located in Berlin, Germany. The prediction of the effective diffusion coefficient can also be transferred to other processes and allows the investigation of materials having temporarily changing pore systems. Examples are the carbonation of cementitious materials, alkali silica reaction, calcium leaching of long-lasting structures, etc. This effect becomes most prominent in the meso-pore range and might alter the effective diffusion coefficient by more than 100 %. T2 - 4th International Congress on Materials & Structural Stability CY - Rabat, Morocco DA - 08.03.2023 KW - Earth masonry KW - Material moisture KW - Molecular diffusion KW - Chemisoprtion KW - Knudsen effect KW - Physisorption PY - 2023 AN - OPUS4-57140 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - von Werder, Julia T1 - Biorezeptive Betonfassaden: Algenbiofilme als Gestaltungselement und zur Verbesserung des Stadtklimas N2 - Der Vortrag fasst den aktuellen Stand der Forschung an der BAM zum Thema "Biorezeptive Betonfassaden" zusammen. Während im Projekt Funktionsbeton der Einfluss der Textur von ultrahochfestem Beton auf die Biorezeptivität im Vordergrund steht, wird im Projekt Algenbiofilmfassade untersucht, inwieweit ein Biofilm künstlich auf Betonsubstraten etabliert werden kann. T2 - BUGG-Tag der Forschung und Lehre Gebäudegrün 2022 CY - Stuttgart, Germany DA - 10.05.2022 KW - Biofilm KW - Biorezeptivität KW - Beton KW - UHPC KW - Fassade PY - 2022 AN - OPUS4-56388 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Voigt, Marieke T1 - Hydration and crystallization of Portland cement at 100 C N2 - For the construction of hot water storage tanks, ultra high performance concrete proofed to be a suitable building material to ensure water tightness. Common storage tanks build with concrete are designed to endure temperatures up to 90 °C. To increase the energy efficiency however, modern tanks need to withstand temperatures above 100 °C. With increasing temperature and correlating water vapor pressures, the cement must meet new requirements. Thermodynamic modelling is a promising tool for predicting the phase stabilities of minerals in the cement within these temperature and pressure ranges (T/P). Thus, mixture designs can be investigated and optimized with regard to the expected mineral phases in selected T/P-ranges. Additionally, predictions of the long-term material behavior can be derived from thermodynamic data and subsequently the experimental effort can be reduced notably. On the other hand, validation of predictions is needed. The base for the thermodynamic model is a thermodynamic equilibrium and thus, the experimental data for validation should approach the presumed conditions of the equilibrium. This study investigates variable experimental conditions for the hydration of Portland cement at 100 °C to reach a sufficiently progressed development of the phase composition. In case of Portland cement, the highest degree of hydration achievable within a reasonable time span is the most significant parameter. Therefore, Portland cement pastes with w/c ratios from 0.4 to 0.6 and dwell times up to three weeks were examined with powder X-ray diffraction to identify mineral phase changes. At 100 °C and high humidity, Portland cement paste shows the expected mineral phases like portlandite, katoite, and remaining clinker phases. The cement pastes with high water content and long dwell time seem to have the highest degree of hydration, even though the AFm phases stabilize with increasing w/c ratio. A dwell time of two weeks and a w/c ratio of 0.5 was found to provide the mineral composition with the highest degree of hydration including the major phase transitions. T2 - 4th International Conference on the Chemistry of Construction Materials (ICCCM) CY - Karlsruhe, Germany DA - 26.09.2022 KW - Hydration KW - High temperature KW - Portland cement PY - 2022 AN - OPUS4-56866 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Voigt, Marieke T1 - The adaption of the set-up for gas permeability measurements for ultra-high performance concrete N2 - In the framework of this project, a steam pressure vessel was to be developed from ultra-high perfor-mance concrete (UHPC) to withstand process temperatures of 200 °C and the respective steam pressure of 15,5 bar. To guarantee the long-term water vapour tightness of the system, the permeability of two UHPC mixtures were tested after long-term cyclic autoclaving. As UPHC shows a high density and therefore low permeability, measurements after the RILEM-Recommendation (TC 116-PCD) reached their detection limit. Therefore, the measurement set-up was adapted to measure the permeability of highly dense UHPC more reliably and quickly. This adaption includes measurements in a higher pres-sure range, the change of sample size thickness and the usage of Ar as a medium compared with the RILEM Recommendation. Additionally, the system was equipped with two pressure sensors and Ar-flowmeters to guarantee a continuous record of the experimental parameters. The new system was tested and evaluated by comparing measurements with the RILEM recommended system. Preliminary results show that the adapted system is capable to provide efficient and reliable results of concrete with low permeability. T2 - 14th fib PhD Symposium in Civil Engineering CY - Rome, Italy DA - 05.09.2022 KW - Hydration KW - High temperature KW - Portland cement PY - 2022 AN - OPUS4-56859 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sperlich, Tim A1 - Häßler, Dustin A1 - Stelzner, Ludwig A1 - Hothan, Sascha T1 - In situ Prüfmethode zur Untersuchung des Feuerwiderstands von bestehenden Stahlkonstruktionen mit reaktivem Brandschutzsystem N2 - Der Beitrag beschreibt die Entwicklung eines neuartigen in situ Nachweisverfahrens zur Beurteilung des Feuerwiderstandes von bestehenden Stahlkonstruktionen mit gealtertem reaktivem Brandschutzsystem (RBS). Derzeit ist ein solcher Nachweis ausschließlich anhand eines Bauteilbrandversuchs möglich. Hierzu muss ein Bauteil aus der Bestandskonstruktion entnommen und einer zerstörenden Brandprüfung unterzogen werden. In Zusammenhang mit der Dauerhaftigkeitsbewertung von RBS für Zeiträume von mehr als 10 Jahren besteht in der Praxis vermehrt der Bedarf an einem minimal invasiven Prüfverfahren, mit dessen Hilfe sich direkt am Bestandsbauwerk die tatsächlich vorhandene Leistungsfähigkeit des gealterten RBS überprüfen lässt. Durch einen erfolgreichen Funktionsnachweis wäre eine Weiternutzung der Bestandkonstruktion bei Aufrechterhaltung des bestehenden Sicherheitsniveaus möglich. T2 - Symposium Heißbemessung - Structural Fire Engineering CY - Braunschweig, Germany DA - 05.09.2023 KW - Brandschutz KW - Stahlbau KW - reaktives Brandschutzsystem KW - Prüfmethode KW - Brandversuch PY - 2023 SP - 1 EP - 16 PB - TU Braunschweig CY - Braunschweig AN - OPUS4-58180 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schönsee, Eric T1 - Calculating rheological properties of fresh mortar for additive manufacturing based on experimental, multi sensor data N2 - Additive manufacturing of concrete structures is a novel and emerging technology. Free contouring in civil engineering, which allows for entirely new designs, is a significant advantage. In the future, lower construction costs are expected with increased construction speeds and decreasing required materials and workers. However, architects and civil engineers rely on a certain quality of execution to fulfil construction standards. Although several techniques and approaches demonstrate the advantages, quality control during printing is highly challenging and rarely applied. Due to the continuous mixing process commonly used in 3D concrete printing, it is impossible to exclude variations in the dry mixture or water content, and a test sample cannot be taken as a representative sample for the whole structure. Although mortar properties vary only locally, a defect in one layer during printing could affect the entire integrity of the whole structure . Therefore, real-time process monitoring is required to record and document the printing process. At the Bundesanstalt für Materialforschung und -prüfung (BAM) a new test rig for the additive manufacturing of concrete is built. The primary purpose is measuring and monitoring the properties of a mortar during the printing process. The following study investigates an approach for calculating yield stress and plastic viscosity based on experimentally recorded pressure data. The calculations assume that fresh mortar behaves as a Bingham fluid and that the Buckingham-Reiner-equation is applicable. A test setup consisting of rigid pipes with integrated pressure sensors at different positions is utilized. Monitoring the printing process with different sensors is crucial for the quality control of an ongoing process. T2 - Non-Tradijtional Cement and Concrete CY - Brno, Czech Republic DA - 25.06.2023 KW - 3DCP KW - Monitoring KW - Additive Manufacturing KW - Rheology KW - Bingham Fluid PY - 2023 AN - OPUS4-58144 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sperlich, Tim T1 - In situ Prüfmethode zur Untersuchung des Feuerwiderstands von bestehenden Stahlkonstruktionen mit reaktivem Brandschutzsystem N2 - Der Beitrag beschreibt die Entwicklung eines neuartigen in situ Nachweisverfahrens zur Beurteilung des Feuerwiderstandes von bestehenden Stahlkonstruktionen mit gealtertem reaktivem Brandschutzsystem (RBS). Derzeit ist ein solcher Nachweis ausschließlich anhand eines Bauteilbrandversuchs möglich. Hierzu muss ein Bauteil aus der Bestandskonstruktion entnommen und einer zerstörenden Brandprüfung unterzogen werden. In Zusammenhang mit der Dauerhaftigkeitsbewertung von RBS für Zeiträume von mehr als 10 Jahren besteht in der Praxis vermehrt der Bedarf an einem minimal invasiven Prüfverfahren, mit dessen Hilfe sich direkt am Bestandsbauwerk die tatsächlich vorhandene Leistungsfähigkeit des gealterten RBS überprüfen lässt. Durch einen erfolgreichen Funktionsnachweis wäre eine Weiternutzung der Bestandkonstruktion bei Aufrechterhaltung des bestehenden Sicherheitsniveaus möglich. T2 - Symposium Heißbemessung - Structural Fire Engineering CY - Braunschweig, Germany DA - 05.09.2023 KW - Brandschutz KW - Stahlbau KW - Reaktives Brandschutzsystem KW - Prüfmethode KW - Brandversuch PY - 2023 AN - OPUS4-58183 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rosenbusch, Sjard Mathis T1 - Mesh-convergence and gradient-enhanced models in blast simulations of concrete structures N2 - Blast experiments on reinforced concrete structures are often limited to small structures and therefore simple shock waves. Such experiments are carried out at the Bundesanstalt für Materialforschung und -prüfung (BAM) and the structural response is investigated using several measuring methods. Complex load scenarios that occur as a result of reflection of the shock wave in larger structures are harder to realise in practice. Numerical simulations for the propagation of the shock wave and the structural response can therefore be an alternative method for the investigation of blast loads on complex structures. For the simulation of concrete under impact and blast loads, several local constitutive models exist that are formulated as plasticity models with softening taken into account by introducing a scalar damage field. Local damage models however often lead to mesh-dependent results which do not converge with mesh refinement. In order to achieve meaningful predictions from numerical experiments, independence from the mesh is needed. In this contribution, the JH2 model (Johnson and Holmquist 1994) with a parameter set for concrete is investigated in a simple blast load scenario. The shockwave is implemented as a simplified Friedlander-curve and the overpressures are applied as a boundary condition for the structural simulation. In order to account for large displacements that can occur during blast loads, an updated Lagrangian formulation is utilised. A Runge-Kutta method with adaptive time stepping is used to advance the solution in time. The open source FEM software FEniCS (Logg et al. 2012) is used together with an implementation of the JH2 model which has been developed at BAM. An extensive convergence analysis with both timestep- and mesh-refinement is carried out to show the mesh dependency. In order to make the results independent of the mesh, possible nonlocal versions of the JH2 model with gradient-enhancement are presented. Since many damage models for concrete share the damage mechanism of the JH2 model, the application of the regularisation methods to more complex material models, like the RHT model (Grunwald et al. 2017), is also discussed. Advantages of a gradient-enhanced formulation to simulate dynamic strength increase of concrete, as suggested in (Häußler-Combe and Kitzig 2009), is discussed as well. T2 - ECCOMAS YIC 2023 CY - Porto, Portugal DA - 19.06.2023 KW - Gradient-Damage KW - Explicit Dynamics KW - Concrete Modeling KW - Mesh Convergence PY - 2023 AN - OPUS4-58717 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Andrés Arcones, Daniel T1 - A Bayesian Framework for Simulation-based Digital Twins of Bridges N2 - Simulation-based digital twins have emerged as a powerful tool for evaluating the mechanical response of bridges. As virtual representations of physical systems, digital twins can provide a wealth of information that complements traditional inspection and monitoring data. By incorporating virtual sensors and predictive maintenance strategies, they have the potential to improve our understanding of the behavior and performance of bridges over time. However, as bridges age and undergo regular loading and extreme events, their structural characteristics change, often differing from the predictions of their initial design. Digital twins must be continuously adapted to reflect these changes. In this article, we present a Bayesian framework for updating simulation-based digital twins in the context of bridges. Our approach integrates information from measurements to account for inaccuracies in the simulation model and quantify uncertainties. Through its implementation and assessment, this work demonstrates the potential for digital twins to provide a reliable and up-to-date representation of bridge behavior, helping to inform decision-making for maintenance and management. T2 - EUROSTRUCT 2023 CY - Vienna, Austria DA - 25.09.2023 KW - Digital Twin KW - Simulation Models KW - Uncertainty Quantification KW - Model Bias PY - 2023 UR - https://eurostruct.org/eurostruct-2023/ AN - OPUS4-58663 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Adwani, D. A1 - Pipintakos, G. A1 - Mirwald, J. A1 - Wang, Y. A1 - Hajj, R. A1 - Guo, M. A1 - Liang, M. A1 - Jing, R. A1 - Varveri, A. A1 - Zhang, Y. A1 - Pei, K. A1 - Xu, X. A1 - Leng, Z. A1 - Li, D. A1 - Villamil, W. A1 - Caro, S. A1 - Chailleux, E. A1 - Cantot, J. A1 - Weigel, Sandra A1 - Škulteckė, J. A1 - Tarsi, G. A1 - Margaritis, A. A1 - Wang, H. A1 - Hu, Y. A1 - Airey, G. A1 - Sreeram, A. A1 - Bhasin, A. T1 - Examining the efficacy of promising antioxidants to mitigate asphalt binder oxidation: Insights from a worldwide interlaboratory investigation N2 - Oxidative aging induces significant stiffening of asphalt binders that leads to a pronounced reduction in the overall durability of asphalt pavements. The strategic implementation of antioxidant additives provides a potential solution to alleviate this issue. This work presents results from the second phase of the global consortium for antioxidants research aimed at investigating the effectiveness of potential antioxidants in increasing the durability of asphalt binders. Sixteen laboratories around the world participated in this effort and a total of 28 binders from diverse geographical regions were tested. Two promising antioxidants, namely zinc diethyldithiocarbamate (ZDC) and kraft lignin were evaluated in this phase and blended with the binders at specific proportions. Subsequently, a comprehensive investigation was conducted to assess rheological characteristics and chemical properties of the various blends, utilising Dynamic Shear Rheometer (DSR) measurements and Fourier Transform Infrared (FTIR) Spectroscopy. The findings indicate that additives such as ZDC hold considerable promise as an effective antioxidant, particularly when considering a wide diversity of binders. In general, its incorporation does not compromise the rutting performance of the binders and significantly improves fatigue performance. Therefore, research efforts should be focused on exploring additional facets to assess its practical applicability in field. KW - Asphalt oxidation KW - Binder aging KW - Antioxidant additives KW - Binder rheology KW - Binder chemistry KW - Bitumen und bitumenhaltige Bindemittel KW - FTIR-Spektroskopie KW - Anwendungsmöglichkeiten KW - Vergleichsuntersuchung KW - Arbeitsanleitung KW - Präzision PY - 2024 DO - https://doi.org/10.1080/10298436.2024.2332363 SN - 1477-268X VL - 25 IS - 1 SP - 1 EP - 15 PB - Taylor & Francis CY - London AN - OPUS4-59957 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Unger, Jörg F. T1 - Coupling of structural and material design N2 - The presentations discusses a use case for the optimization of concrete structures where structural and material design are integrated in a computational workflow. The workflow is based on both physics-based and data-based models and experimental data is used to calibrate/train these models with a specific focus on the integration of ucertainties. T2 - 2nd Technical Meeting of TG.SAG.2 CY - Hannover, Germany DA - 16.04.2024 KW - Coupling of structural and material design KW - Cement Hydration Model PY - 2024 AN - OPUS4-59999 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Unger, Jörg F. T1 - Complex constitutive models in standards N2 - The development of standards that include simulation models is often based on heuristics that include experimental data that is used to calibrate and validate the simulation models. However, these data and the corresponding calibration procedures are usually not part of the publicly accessible documentation making it very difficult to identify gaps in the current standard or extend it to new innovative solutions. The poster shows an adapted procedure that integrates the complete process into a database and a workflow to be published alongside the standard. T2 - NFDI4Ing Gesamtteamtreffen 2024 CY - Hannover, Germany DA - 09.04.2024 KW - Complex constitutive models KW - FAIR Implementation KW - 3D-concrete printing PY - 2024 AN - OPUS4-60043 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Diercks, Philipp A1 - Gläser, D. A1 - Lünsdorf, O. A1 - Selzer, M. A1 - Flemisch, B. A1 - Unger, Jörg F. T1 - Evaluation of tools for describing, reproducing and reusing scientific workflows N2 - In the field of computational science and engineering, workflows often entail the application of various software, for instance, for simulation or pre- and postprocessing. Typically, these components have to be combined in arbitrarily complex workflows to address a specific research question. In order for peer researchers to understand, reproduce and (re)use the findings of a scientific publication, several challenges have to be addressed. For instance, the employed workflow has to be automated and information on all used software must be available for a reproduction of the results. Moreover, the results must be traceable and the workflow documented and readable to allow for external verification and greater trust. In this paper, existing workflow management systems (WfMSs) are discussed regarding their suitability for describing, reproducing and reusing scientific workflows. To this end, a set of general requirements for WfMSswere deduced from user stories that we deem relevant in the domain of computational science and engineering. On the basis of an exemplary workflow implementation, publicly hosted at GitHub (https:// this http URL), a selection of different WfMSs is compared with respect to these requirements, to support fellow scientists in identifying the WfMSs that best suit their requirements. KW - FAIR KW - Reproducibility, scientific workflow KW - Tool comparison KW - Workflow management PY - 2024 UR - https://arxiv.org/abs/2211.06429 DO - https://doi.org/10.48550/arXiv.2211.06429 PB - Arxiv; Cornell Tech CY - New York, NY AN - OPUS4-59804 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Weigel, Sandra T1 - Estimating aging sensitivity of bitumen using FTIR spectroscopy and multivariate evaluation N2 - In this work, a methodology based on Fourier transform infrared (FTIR)spectroscopy and multivariate evaluation is presented to estimate the aging sensitivity of bitumen based on the unaged samples and thus without the need for time- and material-consuming aging simulations. For this purpose, factor analysis and linear discriminant analysis are used to develop a statistical model based on the FTIR spectra of unaged bitumen samples, which can be used fast and simple in everyday laboratory work and allows to assign the bitumen to a low, moderate, or strong aging sensitivity. The evaluation of the aging sensitivity is based on the complex shear modulus|G* | and the phase angle δ from the measurement with a dynamic shear rheometer(DSR), whose aging-related changes were captured as the slope in the Black diagram. A relevant influence on the classification concerning the aging sensitivity has the oxygen-containing compounds(sulfoxide, hydroxyl and partly carbonyl compounds), whereby lower contents and thus less preaged bitumen tend to have a stronger aging sensitivity. However, in addition to the oxygen-containing compounds, the structure of the aliphatic and aromatic compounds and, in particular, the interaction of the different structures are decisive for the aging sensitivity KW - Bitumen KW - Ageing behaviour KW - Characterisation KW - FTIR KW - Multivariate analysis methods PY - 2023 DO - https://doi.org/10.1088/2631-8695/acdce0 SN - 2631-8695 VL - 5 IS - 2 SP - 1 EP - 14 PB - IOP Publishing AN - OPUS4-58020 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schneider, Ronald T1 - Vibration-based system identification of a large steel box girder bridge N2 - The Bundesanstalt für Materialforschung und -prüfung (BAM) collaborates with TNO to develop a software framework for automated calibration of structural models based on monitoring data. The ultimate goal is to include such models in the asset management process of engineering structures. As a basis for developing the framework, a multi-span road bridge consisting of ten simply supported steel box girders was selected as a test case. Our group measured output-only vibration data from one box girder under ambient conditions. From the data, we determined eigenfrequencies and mode shapes. In parallel, we developed a preliminary structural model of the box girder for the purpose of predicting its modal properties. In this contribution, we provide an overview of the measurement campaign, the operational modal analysis, the structural modeling and qualitatively compare the identified with the predicted modes. As an outlook, we discuss the further steps in the calibration process and future applications of the calibrated model. T2 - XII International Conference on Structural Dynamics (EURODYN 2023) CY - Delft, Netherlands DA - 02.07.2023 KW - Bridge KW - Safety KW - Fatigue KW - Modal system identification KW - Model updating PY - 2023 AN - OPUS4-57863 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Weigel, Sandra A1 - Wetekam, J. A1 - Mollenhauer, K. T1 - Identification and classification of PAH in asphalt binders with FTIR spectroscopy and multivariate analysis methods N2 - Reclaimed asphalt pavements (RAP) with increased contents of polycyclic aromatic hydrocarbons (PAH) are restricted for reuse due to their harmful effects on humans and the environment. This work investigated whether Fourier transform infrared (FTIR) spectroscopy is suitable for a fast and simple identification and quantification of PAH in binders recovered from reclaimed asphalts. For this, the binders from 34 RAP samples were recovered using a rapid procedure developed at the Universität Kassel and were examined with infrared spectroscopy. The obtained spectra were pre-processed (Standard Normal Variate transformation, 1st derivative) and evaluated using a combination of factor analysis and linear discriminant analysis. The results showed that various PAH groups with differently pronounced aromatic structures are present in the binders. However, with FTIR spectroscopy combined with the multivariate methods, a statistical model was developed allowing for the differentiation between the PAH groups and also for the distinction between PAH contents below or above the threshold of 25 mg/kg valid in Germany. KW - Polycyclic aromatic hydrocarbons PAH KW - Reclaimed asphalt KW - Rapid procedure for binder extraction KW - FTIR spectroscopy KW - Multivariate analysis methods PY - 2023 DO - https://doi.org/10.1016/j.fuel.2022.126845 SN - 0016-2361 VL - 337 SP - 1 EP - 7 PB - Elsevier Ltd. AN - OPUS4-56961 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Gerards-Wünsche, Paul A1 - Ratkovac, Mirjana A1 - Schneider, Ronald A1 - Hille, Falk A1 - Baeßler, Matthias T1 - A framework for assessing the reliability of crack luminescence – an automated fatigue crack detection system N2 - The new crack luminescence method offers the possibility of making fatigue surface cracks in metallic materials more visible during inspections through a special coating system. This coating system consists of two layers, whereby the first layer has fluorescent properties and emits visible light as soon as it is irradiated by UV light. The top layer is black and is designed to prevent the fluorescent layer from emitting if no crack develops in the underlying material. The technique proved particularly useful in a wide variety of fatigue tests of steel components under laboratory conditions. Moreover, it has the potential to be used in various industrial applications. To enable industrial deployment and integration into maintenance strategies, a concept study is developed in this contribution, resulting in a qualification framework that can serve as a foundation for determining the reliability of the crack luminescence system in terms of a probability of detection curve. Within this study, factors causing measurement variability and uncertainty are being determined and their influences assessed. Due to the extension of the system by a moving computer vision system for automated crack detection using artificial intelligence, additional long-term effects associated with structural health monitoring systems need to be incorporated into an extended probability of detection study as part of the technical justification. Finally, important aspects and findings related to design of experiments are discussed, and a framework for reliability assessment of a new optical crack monitoring method is presented, emphasizing the influence of various uncertainty parameters, including long-term effects such as system ageing. T2 - SPIE Conference Smart Structures + Nondestructive Evaluation 2023 CY - Long Beach, CA, USA DA - 24.03.2023 KW - Structural Health Monitoring KW - Non-Destructive Evaluation KW - Probability of Detection KW - Reliability KW - Artificial Intelligence KW - Computer Vision KW - Crack Luminescence KW - Wind PY - 2023 SN - 978-1-5106-6086-1 DO - https://doi.org/10.1117/12.2658390 SP - 1 EP - 15 AN - OPUS4-57244 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hirsch, T. T1 - Impact of autoclaving on the phase assemblage of Portland cement: Experiment and thermodynamic modelling N2 - Even after autoclaving for 2 weeks in the temperature range of 120 to 200 °C, CEM I paste with a water-to-cement ratio of 0.5 still contains some low-crystalline C-S-H. The conversion of low-crystalline C-S-H to crystalline is faster with increasing temperature. The observed low-crystalline and crystalline C-S-H phases (reinhardbraunsite, jaffeite) indicate that the samples have not reached equilibrium yet under these experimental conditions. However, there is a good agreement between experiment and thermodynamic modelling for the other solids indicating that the used datasets are suitable for this application. T2 - 16th International Congress on the Chemistry of cement 2023 - ICCC2023 CY - Bangkok, Thailand DA - 18.09.2023 KW - Zement KW - Thermodynamik KW - Phasenzusammensetzung KW - Mineralogie KW - Modellierung PY - 2023 UR - https://iccc2023.org AN - OPUS4-58967 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Meng, Birgit A1 - Dehn, F. A1 - Unger, Jörg F. A1 - Shepherd, D. A. A1 - Tamsen, Erik A1 - Pirskawetz, Stephan T1 - Wissensbasierte Digitalisierung von betontechnologischen Materialdaten N2 - Die sprunghaft zunehmende Wichtigkeit von FAIR- und Open-Data für die Qualitätssicherung, aber auch für die Nachnutzbarkeit von Daten und den Erkenntnisfortschritt führt zu enormem Flandlungsbedarf in Forschung und Entwicklung. Damit verbunden laufen derzeit vielfältige, ambitionierte Aktionen, z. B. bezüglich der Erstellung von Ontologien und Wissensgraphen. Das Knowhow entwickelt sich rasant, die Ansätze zur Implementation entstehen in verschiedenen Fachwelten bzw. mit unterschiedlichen Zielsetzungen parallel, so dass recht heterogene Herangehensweisen resultieren. Diese Veröffentlichung fokussiert auf Arbeiten, die derzeit als möglichst ganzheitlicher Ansatz für Materialdaten im Rahmen der Digitalisierungsinitiative „Plattform MaterialDigital" vorangetrieben werden. Die Autoren bearbeiten baustoffbezogene Aspekte im Verbundprojekt „LeBeDigital - Lebenszyklus von Beton". Zielsetzung ist die digitale Beschreibung des Materialverhaltens von Beton über den kompletten Herstellungsprozess eines Fertigteils mit einer Integration von Daten und Modellen innerhalb eines Workflows zur probabilistischen Material- und Prozessoptimierung. Es wird über die Vorgehensweise und die dabei gewonnenen Erfahrungen berichtet, nicht ohne den Blick auf die oft unterschätzte Komplexität der Thematik zu lenken. T2 - Internationale Baustofftagung (ibausil) CY - Weimar, Germany DA - 13.09.2023 KW - Beton KW - Digitalisierung KW - Materialdaten KW - Datenmanagement KW - FAIR-Prinzip KW - Metadaten KW - Ontologie KW - Wissengraph PY - 2023 UR - https://www.uni-weimar.de/de/bauingenieurwesen/institute/fib/ibausil/ VL - 2023 SP - 1 EP - 11 PB - Sonderausgabe des Online-Journals ce/papers von Wiley AN - OPUS4-58315 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Stohl, Leonie A1 - Manninger, T. A1 - von Werder, Julia T1 - Biofilmfassaden; Begrünung von Beton auf der Mikroskala N2 - Die Klimakrise führt zu einer steigenden Nachfrage nach ökologisch orientierten Konzepten. Dazu gehören im Baubereich nicht nur umweltfreundliche Materialien, sondern auch die Begrünung städtischer Gebiete. Vor diesem Hintergrund wird ein Projekt vorgestellt, dass eine Fassadenbegrünung mithilfe von mikrobiellen Organismen wie Algen statt höheren Pflanzen realisieren will. Die Entwicklung von sogenannten biorezeptiven Materialien ist eine Herausforderung, weil es aktuell noch keine standardisierten Methoden zur Bestimmung der Biorezeptivität gibt. Um ein grundlegendes Verständnis für die Prozesse und Interaktionen zwischen Organismen und Substrat zu gewinnen, werden Betonplatten unterschiedlich strukturiert und ihre Oberflächencharakteristiken dokumentiert. Anschließend werden die Platten unter verschiedensten Bedingungen bewittert und auf ihre Biorezeptivität untersucht. Von besonderem Interesse sind hierbei Einfluss der materialintrinsischen Oberflächenparameter sowie der Umwelt. Langfristig wird geplant ein geeignetes Messkonzept vorzuschlagen, das Materialwissenschaft und Biologie verbindet und verlässliche Vorhersagen zur Biorezeptivität eines Materials treffen kann. In der vorliegenden Arbeit liegt der Schwerpunkt auf dem theoretischen Ansatz und der Versuchsplanung. T2 - Internationale Baustofftagung (ibausil) CY - Weimar, Germany DA - 13.09.2023 KW - Biorezeptivität KW - Beton KW - Fassadenbegrünung KW - pH-Messungen KW - Rauheit KW - Benetzungsverhalten KW - Materialdesign PY - 2023 UR - https://www.uni-weimar.de/de/bauingenieurwesen/institute/fib/ibausil/ SP - 1 EP - 8 PB - Sonderausgabe des Online-Journals ce/papers von Wiley AN - OPUS4-58303 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Fladt, Matthias A1 - Weise, Frank T1 - Bewertung der Innenhydrophobierung als neuartige AKR-Vermeidungsstrategie bei Betonfahrbahndecken N2 - Zur Vermeidung von AKR-Schäden an Betonfahrbahndecken im deutschen Autobahnnetz wurden mit dem ARS 04/2013 verbindliche Eignungsprüfungen zum Ausschluss alkaliempfindlicher Gesteinskörnungen bei Neubau- und Erhaltungsmaßnahmen eingeführt. Das hatte eine signifikante Reduzierung geeigneter Gesteinskörnungen zur Folge. Deshalb wird geprüft, ob durch die Zugabe eines Hydrophobierungsmittels während der Betonherstellung grenzwertig alkaliempfindliche Gesteinskörnungen nutzbar gemacht werden können. In diesem Beitrag wird der Einfluss der Dosierung eines Compounds mit Hydrophobierungsmittel (HM) auf die Frisch- und Festbetoneigenschaften eines Waschbetons mit einer reaktiven Grauwacke dargestellt. Es zeigt sich, dass aufgrund des Antagonismus die zunehmende Dosierung des HM-Compounds eine signifikante Erhöhung der Zugabe des Luftporenbildners auf Wurzelharzbasis erfordert. Der AKR-Schädigungsprozess wird ab einer Dosierung des HM-Compounds von 0,75 M.-%, bezogen auf den Zementgehalt, hinreichend vermindert. Die mechanischen Eigenschaften des hydrophobierten Waschbetons verschlechtern sich im betrachteten Dosierungsbereich des HMCompounds nur geringfügig. Auch der Frost-Tausalz-Widerstand vermindert sich, ohne den normativen Grenzwert für die Abwitterung zu überschreiten. T2 - Internationale Baustofftagung (ibausil) CY - Weimar, Germany DA - 13.09.2023 KW - Betonfahrbahndecke KW - Alkali-Kieselsäure-Reaktion KW - Massenhydrophobierung KW - AKRVermeidungsstrategie PY - 2023 UR - https://www.uni-weimar.de/de/bauingenieurwesen/institute/fib/ibausil/ VL - 2023 SP - 1 EP - 10 PB - Sonderausgabe des Online-Journals ce/papers von Wiley AN - OPUS4-58317 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Stohl, Leonie A1 - von Werder, Julia A1 - Manninger, T. T1 - Bioreceptive concrete: Greening facades on the microscale N2 - The accelerating climate crisis results in a rising demand for ecologically driven concepts. Regarding construction, this does not only include environmentally friendly materials but also the establishment of greenery in urban regions. This contribution presents the progress of two projects in which textured concrete slabs were designed to grow a stable biofilm of photosynthetic eukaryotic organisms. The greened panels represent an alternative to classic fa9ade greening with plants. Current literature suggests that the development of bioreceptive surface materials in the construction sector is difficult because there are no standardized methodological approaches for measuring said bioreceptivity. Therefore, the long-term. ahn is proposing a suitable measurement concept combining material Science and biology. Among other things, the intrinsic Substrate property pH value is expected to have a significant influence on biological colonization. In the current contribution the focus lies on the theoretical approach and design of experiment regarding this parameter. Available experimental data will be presented. T2 - 77th RILEM Annual Week and the 1st Interdisciplinary Symposium on Smart & Sustainable Infrastructures (ISSSI 2023) CY - Vancouver, Canada DA - 04.09.2023 KW - Bioreceptivity KW - Concrete KW - Surface pH measurement KW - Material characterization KW - Green Facade PY - 2023 UR - https://www.rilemweek2023.com/submissions/ SP - 1 EP - 6 AN - OPUS4-58304 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Jafari, Abbas T1 - Bayesian finite element model updating using full-field measurements of displacements N2 - Finite element (FE) models are widely used to capture the mechanical behavior of structures. Uncertainties in the underlying physics and unknown parameters of such models can heavily impact their performance. Thus, to satisfy high precision and reliability requirements, the performance of such models is often validated using experimental data. In such model updating processes, uncertainties in the incoming measurements should be accounted for, as well. In this context, Bayesian methods have been recognized as a powerful tool for addressing different types of uncertainties. Quasi-brittle materials subjected to damage pose a further challenge due to the increased uncertainty and complexity involved in modeling crack propagation effects. In this respect, techniques such as Digital Image Correlation (DIC) can provide full-field displacement measurements that are able to reflect the crack path up to a certain accuracy. In this study, DIC-based full field measurements are incorporated into a finite element model updating approach, to calibrate unknown/uncertain parameters of an ansatz constitutive model. In contrast to the standard FEMU, where measured displacements are compared to the displacements from the FE model response, in the force-version of the standard FEMU, termed FEMU-F [1], displacements are applied as Dirichlet constraints. This enables the evaluation of the internal forces, which are then compared to measured external forces, thus quantifying the fulfillment of the momentum balance equation as a metric for the model discrepancy. In the present work, the FEMU-F approach is further equipped with a Bayesian technique that accounts for uncertainties in the measured displacements, as well. Via this modification, displacements are treated as unknown variables to be subsequently identified, while they are allowed to deviate from the measured values up to a certain measurement accuracy. To be able to identify many unknown variables; including constitutive parameters and the aforementioned displacements, the Variational Bayesian technique proposed in [2] is utilized as an approximative technique. A numerical example of a three-point bending case study is presented first to demonstrate the effectiveness of the proposed approach. The parameters of a gradient-enhanced damage material model [4] are identified using noisy synthetic data, and the effect of measurement noise is studied. The ability of the suggested approach on identifying constitutive parameters is then validated using real experimental data from a three-point bending test from [3]. The full field displacements required as input to the inference setup are extracted through a digital image correlation (DIC) analysis of the provided raw images. T2 - GACM-2023 - 10th GACM Colloquium on Computational Mechanics 2023 CY - Vienna, Austria DA - 10.09.2023 KW - Bayesian model updating KW - Full-field measurements KW - Gradient damage model PY - 2023 AN - OPUS4-58288 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Jafari, Abbas T1 - Bayesian updating of constitutive laws for Finite Element simulation using full field measurements N2 - Developed finite element (FE) models have been recognized as powerful tools for predicting the mechanical behaviour of engineered systems. As a prerequisite, those models need to be improved with respect to various uncertainties; most notably, concerning underlying physics assumptions and unknown parameters. This is very often accomplished by comparing the performance of a model (e.g. the model response) against available data measured from real experiments. Another challenge emerges in doing that, however, which is accounting for uncertainties of measured data. Bayesian methods have been widely considered and utilized as a suitable approach for coping with and quantifying the aforementioned uncertainties. Phenomena like damage - in particular in quasi-brittle materials - introduce further uncertainties due to the complexity underlying the crack propagation of phenomenon. This implies that, the fitting of a numerical model and an associated constitute law that can adequately describe such effects is non-trivial. The standard approach of finite element model updating (FEMU) is therefore modified to account for tracking of the crack propagation, as recorded during an experiment under increasing loading, via full field displacement measurements. The latter are fed as Dirichlet constraints to an available finite element model, leading to the evaluation of force residuals, which quantifies the accuracy of the model. This approach - which is known as FEMU-F (force-version of the standard FEMU) [1] - is here further equipped with a Bayesian technique, which accounts for the measurement uncertainties in the full field displacement. This is achieved by penalizing the discrepancy between the measured displacements and the modeled Dirichlet constraints, where the latter are considered as further unknowns. We specifically employ the Variational Bayesian technique, proposed in [2], as an approximating tool for the estimation of posterior parameters, including displacement variables that are allowed to deviate from the measurements. A Markov chain Monte Carlo (MCMC) is also used for sampling the posterior distribution of the unknown model parameters. The model updating procedure is first demonstrated through a numerically simulated example of threepoint bending, where the parameters of a gradient-enhanced damage material model [4] are identified in accordance with synthetic noisy data (displacements and reaction forces). For the validation, experimental data from a three-point bending test are used, where full field displacements are collected through a digital image correlation (DIC) analysis (raw data taken from [3]). The data is then used for the parameter identification of a gradient damage constitutive law, which is employed as an ansatz model T2 - 5th International Conference on Uncertainty Quantification inUNCECOMP 2023 - Computational Science and Engineering CY - Athens, Greece DA - 12.06.2023 KW - Bayesian model updating KW - Full field measurements KW - Gradient damage model PY - 2023 AN - OPUS4-58287 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Baeßler, Matthias A1 - Balscheit, Hagen A1 - Schepers, Winfried A1 - Victor, Albrecht A1 - Daryaei, Reza A1 - Bianco, Marcelo A1 - Starost, Christina T1 - Close-out Webinar OWA VERBATIM N2 - The risk of pile base buckling is a major reason for high pile wall thicknesses in monopiles. The VERBATIM project - Verification of the buckling detection and behaviour of large monopiles - aimed to investigate buckling phenomena related to both the plastic deformation of the pile tip during installation and the buckling of the embedded pile near the seabed. Numerical models were developed and validated on the basis of extensive tests. This enables a better understanding of the buckling behaviour in order to reduce the wall thickness, which allows cost savings in the amount of steel and the development of safer and optimised structures. The previous design procedures were able to ensure the successful installation of the monopiles. However, as the size of monopiles continues to increase, the development of improved design methods for safe and cost-effective foundations is becoming increasingly important. The presentation provides an overview of the investigations carried out and the results. T2 - Webinar Carbon Trust Offshore Wind Accelerator CY - Online meeting DA - 22.05.2024 KW - Offshore Windenergy Pile Buckling PY - 2024 AN - OPUS4-60348 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Eiz Eddin, Ahmad A1 - Stelzner, Ludwig A1 - Häßler, Dustin A1 - Hothan, Sascha T1 - Zum Feuerwiderstand von filigranen Deckenelementen aus vorgespanntem Carbonbeton N2 - Der Einsatz von hoch zugbeanspruchbarem und korrosionsbeständigem Carbongelege anstelle von herkömmlichem Spannstahl ermöglicht es Beton vorzuspannen und gleichzeitig die Betondeckung auf ein für den Verbund nötiges Minimum zu reduzieren. Das Carbongelege besteht aus Carbonfasern in einer Kunststoffmatrix. Mit dieser Bauweise können dünnwandige und damit ressourcenschonende Deckenelemente realisiert werden. Der Wechsel von massiven zu filigranen und vergleichsweise leichten Bauteilen führt jedoch aufgrund der geringeren Masse und der damit einhergehenden schnelleren Erwärmung zu einer Abnahme des Feuerwiderstands. Ferner führt die Erweichung der Matrix im Brandfall zu einer Abnahme der Verbundfestigkeit zwischen Carbongelege und Beton. Die Brennbarkeit des Carbongeleges sowie die Abplatzneigung des verwendeten Feinbetons stellen weitere Herausforderungen für den baulichen Brandschutz dar. Der Beitrag stellt Versuchsergebnisse zum Abplatz- und Hochtemperaturverhalten von Carbonbeton vor, die im Rahmen des Verbundvorhabens „Vorgespannte Carbonbetondecken mit reduzierten Querschnitten“ (CaPreFloor) erzielt wurden. Für die Untersuchung der Tragfähigkeit bei hohen Temperaturen wurden 4-Punkt-Biegeversuche an balkenförmigen Prüfkörpern (150 x 30 x 6 cm³) mit einlagiger Carbonbewehrung und instationärer Temperaturbeanspruchung durchgeführt. Neben dem Vorspanngrad des Carbongeleges wurde auch der Gelegetyp variiert. Im Bereich der konstanten Biegezugzone erfolgt die einseitige Erwärmung mittels elektrisch betriebener Heizmatten. Während der kontinuierlichen Erwärmung werden die Prüfkörper mit einer konstanten Kraft belastet, deren Betrag aus zuvor durchgeführten Biegeversuchen bei Raumtemperatur abgeleitet wurde. Die Abplatzversuche werden mit Einheits-Temperaturzeitkurve an rechteckigen (60 x 60 x 6 cm³) und kreisrunden (Ø 47 x 6 cm³), plattenförmigen Prüfkörpern am 1m³-Ofen der BAM durchgeführt. Die kreisrunden Prüfkörper sind zusätzlich mit einem Stahlring zur Behinderung der thermischen Dehnung des Betons versehen. Um den Einfluss des Geleges auf das Abplatzverhalten zu analysieren, werden sowohl Prüfkörper mit Carbongelege als auch unbewehrte Prüfkörper untersucht. Die daraus resultierenden Erkenntnisse fließen in die weitere Entwicklung der vorgespannten Carbonbetondeckenelemente ein. Anhand von realmaßstäblichen Brandversuchen wird der Feuerwiderstand dieser Bauteile im weiteren Projektverlauf bestimmt. T2 - Symposium Heißbemessung 2024 CY - Braunschweig, Germany DA - 24.09.2024 KW - Carbonbeton KW - Feuerwiderstand KW - Brandversuch KW - Carbon PY - 2024 SP - 23 EP - 39 AN - OPUS4-61253 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Eichner, Lukas A1 - Thiele, Marc A1 - Hille, Falk A1 - Baeßler, Matthias T1 - Digitale Modellierungsprozesse in der wiederkehrenden Prüfung von Windenergieanlagen - DiMoWind-Inspect - Abschlusstreffen N2 - Dieses Dokument enthält die Präsentationsfolien des BAM-Teams beim Abschlusstreffen des Forschungsprojekts DiMoWind-Inspect. Es wurden die Arbeitspakete Datenmanagement, Referenzkennzeichnungssystem, Grundlagen der Schadensbewertung, Risikobasierte Inspektions- und Instandhaltungsplanung und Schadensdetektion mittels Risslumineszenz sowie eine abschließende Bewertung des Projekts vorgestellt. T2 - DiMoWind-Inspect - Abschlusstreffen CY - Berlin, Germany DA - 12.09.2024 KW - Building Information Modeling (BIM) KW - Referenzkennzeichnungssystem KW - Risslumineszenz (Riluminati) KW - Risikobasierte Inspektionsplanung (RBI) PY - 2024 AN - OPUS4-61054 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Andrés Arcones, Daniel T1 - Bias Identification Approaches for Model Updating of Simulation-based Digital Twins of Bridges N2 - Simulation-based digital twins of bridges have the potential not only to serve as monitoring devices of the current state of the structure but also to generate new knowledge through physical predictions that allow for better-informed decision-making. For an accurate representation of the bridge, the underlying models must be tuned to reproduce the real system. The updated model can be eventually used for the extension of the service life of the bridge based on an accurate description of the structure. Nevertheless, the necessary assumptions and simplifications in these models irremediably introduce discrepancies between measurements and model response. We will prove that quantifying the extent of the uncertainties generated by said discrepancies provides a better understanding of the real system, enhances the model updating process, and creates more robust and trustworthy digital twins. Among others, we identify that the inclusion of the explicit bias term through a Bayesian inference framework corrects the tuned parameters, allows the identification of non-prescribed noise sources and enables the introduction of additional information in the system without modifying the simulation model. The performance of selected model bias identification approaches will be compared in the context of digital twins of bridges. The different methods will be applied to a representative demonstrator case based on the Nibelungenbrücke of Worms. The findings from this work are englobed in the initiative SPP 100+, whose main aim is the extension of the service life of structures through monitorization and digitalization, especially through the implementation of digital twins. T2 - 11th European Workshop on Structural Health Monitoring CY - Potsdam, Germany DA - 10.06.2024 KW - Digital Twin KW - Simulation Models KW - Uncertainty Quantification KW - Model Bias PY - 2024 AN - OPUS4-61024 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Eiz Eddin, Ahmad T1 - Innovative lightweight floors made of prestressed CFRP-reinforced concrete from research to construction practice N2 - The presented joint research project “CaPreFloor”, which started in 2023, aims to revolutionise the building construction practice by employing prestressed textile-reinforced concrete using carbon-fiber-reinforced polymer (CFRP) for the design of lightweight floor elements. This allows the reduction of common steel reinforced concrete floors of 30 cm thickness to 10 cm for office, residential, and hotel buildings. Lower material consumption significantly contributes to the conservation of resources and minimises the carbon footprint. In addition, the prefabrication of these floor elements leads to high and consistent quality, short construction times and enhanced reusability of the components. A team of experts from various fields of research and practice is working on this project to achieve the set goal. T2 - XI International Symposium on Fiber Reinforced Concrete (Befib 2024) CY - Dresden, Germany DA - 16.09.2024 KW - Fire Resistance KW - Sound protection KW - Ceiling KW - Concrete KW - CFRP PY - 2024 AN - OPUS4-61126 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Stohl, Leonie T1 - MI Funktionsbeton: Funktionalisierte Betonoberflächen zur gezielten Einstellung der Biorezeptivität N2 - Beschreibung des Projektes MI Funktionsbeton 1462, Update nach 15 Monaten. Der Bericht umfasst Hintergrund, Projektzeitplan und aktuellen Stand. KW - Biorezeptivität KW - Beton KW - Biofilm KW - Struktur PY - 2022 SP - 1 EP - 13 AN - OPUS4-58376 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schwettmann, K. A1 - Nytus, N. A1 - Weigel, Sandra A1 - Radenberg, M. A1 - Stephan, D. T1 - Effects of rejuvenators on bitumen ageing during simulated cyclic reuse: A review N2 - Single reuse of asphalt is an approved practice, but its success highly depends on restoring the properties of the aged binder. Rejuvenators have become increasingly important for softening the binder because they make it possible to increase the amount of reclaimed asphalt pavement (RAP) while reducing the dependence on virgin bitumen. The vital questions to be investigated are how the rejuvenators affect the ageing properties of bitumen and if rejuvenators offer the possibility of cyclic bitumen reuse. The main objective of this publication is to present the current state of the art regarding the effects of rejuvenators on bitumen ageing. The results of laboratory life cycle simulations indicate that repetitive ageing and rejuvenation processes are possible, but reuse mainly depends on the rejuvenator type and its interaction with the respective bitumen sample. There are rejuvenators that have good rejuvenating properties but accelerate subsequent ageing, which is essential to consider when evaluating a rejuvenator. Bitumen rejuvenated with petroleum-based products, such as aromatic extracts, performs slightly better after subsequent ageing than when rejuvenated with bio-based products. As there are a limited number of studies simulating cyclic bitumen reuse, more studies are necessary to evaluate the general limits of bitumen reuse. KW - Bitumen KW - Asphalt KW - Ageing KW - Rejuvenator KW - Recycling KW - Cyclic reuse KW - Multiple reuse PY - 2023 DO - https://doi.org/10.1016/j.resconrec.2022.106776 SN - 0921-3449 VL - 190 SP - 1 EP - 14 PB - Elsevier B.V. AN - OPUS4-56963 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Mezhov, Alexander A1 - Ben Shir, I. A1 - Schmidt, A. A1 - Kovler, K. A1 - Diesendruck, Ch. E. T1 - Retardation mechanism of cement hydration by a comb polyphosphate superplasticizer N2 - The retardation mechanism of cement hydration as imparted by the addition of polyphosphate comb superplasticizer to model cement containing C3S, C3A and calcium sulfate hemihydrate is studied using XRD, ss NMR and calorimetry. Our findings show the retardation effect caused by the direct addition of polyphosphate comb superplasticizer differs significantly to that of conventional polycarboxylate superplasticizers. Conversely to polycarboxylates, polyphosphates, at a low dosage, inhibits the silicate reaction without affecting the aluminate reaction and formation of ettringite. Yet, at high doses, both reactions are hampered, and the induction period extended, followed by accelerated aluminate and silicate reactions. KW - Superplasticizer KW - Polyphosphate KW - Retardation KW - Cement hydration PY - 2022 DO - https://doi.org/10.1016/j.conbuildmat.2022.128698 SN - 0950-0618 VL - 352 SP - 1 EP - 13 PB - Elsevier Ltd. AN - OPUS4-58246 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Lapiro, I. A1 - Mezhov, Alexander A1 - Kovler, K. T1 - Performance of corrosion inhibitors in reinforced concrete elements under electrical voltage N2 - The current paper develops a novel accelerated corrosion test method based on Faraday’s law to investigate the performance of different inhibitors in reinforced concrete elements under electrical voltage. Using the proposed method two commercially available and three lab-made inhibitors were tested. Lab-made inhibitors based on potassium fluorosilicate and amine carboxylate showed the best performance over others. Furthermore, it is found that under an electrical potential environment beyond 3.6 V, the higher the concrete strength, the more efficient is the corrosion inhibition. Based on experimental results, a novel model describing the corrosion evolution in reinforced concrete was proposed. KW - Steel corrosion KW - Reinforced concrete KW - Accelerated test KW - Corrosion inhibitor KW - Stray current PY - 2022 DO - https://doi.org/10.1016/j.conbuildmat.2022.127656 SN - 0950-0618 VL - 342 IS - 342 SP - 1 EP - 10 PB - Elsevier Ltd. AN - OPUS4-58249 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Andrés Arcones, Daniel A1 - Weiser, M. A1 - Koutsourelakis, F.-S. A1 - Unger, Jörg F. T1 - Evaluation of Model Bias Identification Approaches Based on Bayesian Inference and Applications to Digital Twins N2 - In recent years, the use of simulation-based digital twins for monitoring and assessment of complex mechanical systems has greatly expanded. Their potential to increase the information obtained from limited data makes them an invaluable tool for a broad range of real-world applications. Nonetheless, there usually exists a discrepancy between the predicted response and the measurements of the system once built. One of the main contributors to this difference in addition to miscalibrated model parameters is the model error. Quantifying this socalled model bias (as well as proper values for the model parameters) is critical for the reliable performance of digital twins. Model bias identification is ultimately an inverse problem where information from measurements is used to update the original model. Bayesian formulations can tackle this task. Including the model bias as a parameter to be inferred enables the use of a Bayesian framework to obtain a probability distribution that represents the uncertainty between the measurements and the model. Simultaneously, this procedure can be combined with a classic parameter updating scheme to account for the trainable parameters in the original model. This study evaluates the effectiveness of different model bias identification approaches based on Bayesian inference methods. This includes more classical approaches such as direct parameter estimation using MCMC in a Bayesian setup, as well as more recent proposals such as stat-FEM or orthogonal Gaussian Processes. Their potential use in digital twins, generalization capabilities, and computational cost is extensively analyzed. T2 - 5th ECCOMAS Thematic Conference on Uncertainty Quantificationin Computational Sciences and Engineering CY - Athen, Greece DA - 12.06.2023 KW - Model bias KW - Bayesian Uncertainty Quantification KW - Digital Twins KW - Gaussian Processes KW - Statistical Finite Element Method PY - 2023 UR - https://2023.uncecomp.org/ SP - 1 EP - 15 AN - OPUS4-58227 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ebell, Gino A1 - Scheerer, S. A1 - Fiedler, M. A1 - Schacht, G. A1 - Ritter, R. A1 - Marzahn, G. A1 - Marx, S. T1 - Die wechselvolle Geschichte der Carolabrücke in Dresden N2 - Am 11. September 2024 fand in Dresden ein Ereignis statt, welches man in Deutschland nicht erwartet hatte: der Teileinsturz einer Spannbetonbrücke unter Betrieb ohne Vorankündigung. Die Dresdner Carolabrücke war eine Ikone der Ingenieurbaukunst ihrer Zeit. Sie war ein sehr ästhetisches und schlankes Bauwerk. Ihre Konstruktion und Bau wären auch heute noch eine Herausforderung. Die vorhandenen Unterlagen zeugen von einer hohen Entwurfsqualität und einer sehr sorgsamen Bauausführung. Im Beitrag werden die Entstehungsgeschichte, die Konstruktion selbst und der Bau der Brücke vorgestellt. Es wird der Versuch der Rekonstruktion des Einsturzvorgangs unternommen und die Suche nach der Einsturzursache beschrieben. Am Schluss des Beitrags wird auf das aktuelle Überwachungskonzept eingegangen und ein Ausblick auf das mögliche weitere Vorgehen gegeben. T2 - 34. Dresdner Brückenbausymposium CY - Dresden, Germany DA - 19.03.2025 KW - Spanungsrisskorrosion KW - Wasserstoff KW - Spannstahl KW - Brücke PY - 2025 SP - 15 EP - 33 CY - Dresden AN - OPUS4-63063 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Heyn, A. A1 - Kotula, Stefan A1 - Ebell, Gino A1 - Babutzka, M. T1 - Results of a Round Robin Test for the Determination of Polarization Resistances on Differently Weathered Zinc Samples Using Gel Electrolytes N2 - This article presents the results of a round robin test throughout Germany with 19 participating institutions. Corrosion productlayer resistances (RL ) were determined on two differently weathered pure zinc samples and a sample activated with NaOH bymeans of electrochemical measurement of the linear polarization resistance (LPR) using agar‐based gel electrolytes. The roundrobin test was organized by the Bundesanstalt für Materialforschung und ‐prüfung (BAM) in Berlin. The measurements werecarried out by the participants in the period from May to July 2021. The results are summarized in this article comprising anassessment of the reproducibility and repeatability of the measurements. The methodology is suitable for distinguishing zincsurfaces after exposure to different atmospheres based on the corrosion product layer resistances (RL). In addition, possibleproblems in the application of the method were identified, and solutions for improving reproducibility and repeatability arediscussed. The results and knowledge from the round robin test are incorporated into a new test standard (DIN 50023:2024‐07)for this measurement method KW - Corrosion PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-630546 DO - https://doi.org/10.1002/maco.202414696 SN - 1521-4176 SP - 1 EP - 12 PB - Wiley AN - OPUS4-63054 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ebell, Gino T1 - Merkblatt B 03 der dgzfp Ausgabe Mai 2025 N2 - Durch das alkalische Porenwassermilieu ist Stahl im Beton vor Korrosion geschützt. Unter ungünstigen Umgebungsbedingungen (Karbonatisierung, Chlorideintrag) kann die passive Deckschicht auf der Stahloberfläche zerstört werden. Im weiteren Verlauf können sich korrosionsbedingte Folgeschäden, wie Risse und Abplatzungen am Bauwerk ergeben. Um notwendige Sanierungsmaßnahmen sind frühzeitige und weitgehend zerstörungsfrei ermittelte Informationen über das aktuelle Korrosionsverhalten der Stahlbewehrung von großer Bedeutung. Die Potentialfeldmessung ist ein etabliertes und weit verbreitetes Verfahren zur Beurteilung des Korrosionszustandes der Bewehrung in Stahlbetonbauwerken. Mit Hilfe dieses Verfahrens können Bereiche aktiv korrodierender Bewehrung zerstörungsfrei lokalisiert werden. In der Regel kommt diese Messmethode bei der Detektion chloridinduzierter Korrosion zum Einsatz. Wie und unter welchen Randbedingungen dieses Messverfahren zielführend eingesetzt werden kann, ist im Merkblatt B 03 der dgzfp erörtert.… T2 - Sachkundelehrgang Potentialfeldmessung CY - Aachen, Germany DA - 03.06.2025 KW - Korrosion KW - Potentialfeldmessung PY - 2025 AN - OPUS4-63306 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ebell, Gino T1 - Spannstahlbrücken der Vergangenheit in der Zukunft richtig bewerten N2 - Spannstahlbrücken die in der Vergangenheit mir vergüteten Spannstählen errichtet worden sind können unter ungünstigen Gegebenheiten bei deren Erstellung signifikante Probleme hinsichtlich der Tragfähigkeit bekommen. Im Speziellen kann die wasserstoffinduzierte Spannungsrisskorrosion hier bei der Errichtung der Brückenbauwerke Anrisse an den Spanndrähten erzeugt haben die Jahre später zum Versagen der Brücke führen können. Die Präsentation im Speziellen behandelt den Teileinsturz der Carolabrücke in Dresden. T2 - Sitzung Arbeitskreis Korrosionsschutz im konstruktiven Korrosionsschutz CY - Aachen, Germany DA - 14.05.2025 KW - Korrosion KW - Spannstahl KW - Spannungsrisskorrosion KW - Wasserstoff PY - 2025 AN - OPUS4-63132 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ebell, Gino A1 - Huckshold, M. T1 - Forschung zum Feuerverzinken "Rückblick - Gegenwart - Ausblick" N2 - Darstellung der Forschungsaktivitäten im Bereich der Feuerverzinkungsaktivitäten seit 1951. Vortrag zu aktuellen Forschungsentwicklungen im Bereich des Einsatzes feuerverzinkter Produkte in Infrastrukturprojekten. T2 - Branchentreffen 2025 CY - Munich, Germany DA - 15.05.2025 KW - Feuerverzinken KW - Korrosion PY - 2025 AN - OPUS4-63153 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ebell, Gino T1 - Exposure Site 41 Berlin N2 - The United Nations Educational, Social and Cultural Organization (UNESCO) is establishing a project with the objective of investigating the role of air pollution in the acceleration of ongoing corrosion processes and the resulting corrosion intensity. Consequently, since the early 1980s, research has been conducted on 60 different exposure sites. The Bundesumweltamt has mandated the BAM to oversee a designated test sites, a responsibility that the BAM has accepted since 2024. The presentation will provide a visual representation of the newly constructed test site, in addition to the inaugural results of 2024. T2 - UNESCO Materials RISE Meeting CY - Prague, Czech Republic DA - 05.05.2025 KW - Korrosion KW - Corrosion PY - 2025 AN - OPUS4-63080 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - RPRT A1 - Ebell, Gino A1 - Raupach, M. A1 - Sankaran, Shivasarathy A1 - Driessen, C. A1 - Helm, C. T1 - Leistungsfähigkeit von galvanischen und hybriden Anodensystemen für Stahlbetonbauwerke N2 - Die in diesem Forschungsvorhaben untersuchten Anodensysteme sind für die Anwendung als diskrete Anoden im Rahmen einer Installation unter klassischen Aspekten des KKS-B nicht zu verwenden. Alle untersuchten Systeme unterliegen mit der Zeit einer zunehmenden anodischen Hemmung infolge der Bildung von Korrosionsprodukten. Diese erhöhen den Diffusionswiderstand im Phasengrenzbereich und haben dort einen signifikanten Einfluss auf die thermodynamischen Gleichgewichtsbedingungen, infolge derer die Eigenkorrosion über die Zeit ebenfalls abnimmt. Die Installation der Systeme A1, A2 sowie C bei höheren Bauteilfeuchten kann zur Vermeidung des sogenannten Anodenringeffektes verwendet werden. Eine Modellbildung für eine effektive Nutzungsdauer kann unter Hinzuziehung der ermittelten elektrochemischen Parameter nicht zielführend erfolgen. Nutzungsdauern von 1 bis 2 Jahren können grundlegend mit den Anodensystemen A1, A2 und C erreicht werden, hierzu müssen aber ausreichend hohe Bauteilfeuchten gewährleistet werden. Die theoretischen Lebensdauern aus der numerischen Simulation der galvanischen Elemente berücksichtigen eine Änderung der anodischen Teilstromdichte über die Zeit nicht und gehen von ungehemmten, aktiv korrodierenden Anoden aus. Eine Reduktion der Korrosionsaktivität wird äquivalent durch den Anstieg des Polarisationswiderstandes gespiegelt und zeigt, dass die Systeme in ihrer Lebensdauer auf Basis einer zunehmenden, deckschichtbasierten, anodischen Hemmung limitiert sind. Die Bauteilfeuchten haben grundlegend einen signifikanten Einfluss auf die Korrosionsaktivität und die daraus resultierende Effektivität der verbauten Anoden. Der höhere Ladungsumsatz führt jedoch auch zwangsläufig zu einer beschleunigten Deckschichtbildung, was im Umkehrschluss zu einem vorzeitigen Versagen der Anodensystem gegenüber dem Einsatz unter geringeren Bauteilfeuchten führen kann. Auf Basis der Ergebnisse aus den Arbeitspaketen muss festgehalten werden, dass das Ziel des Forschungsvorhabens nur teilweise erreicht wurde. Hybride Anodensysteme, die unter Fremdstrombetrieb agieren, konnten mangels Verfügbarkeit nicht untersucht werden. Einbettmörtel der Hersteller konnten nicht untersucht werden, die pastösen Einbettmittel haben aufgrund der schlechten Performance in Wechselwirkung mit den Anoden keinen Anlass gegeben, diese weitergehenden Untersuchungen zu unterziehen. KW - Korrosion KW - Galvanische Anoden PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-574919 SP - 1 EP - 91 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-57491 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Ebell, Gino A1 - Mayer, T. F. A1 - Harnisch, J. A1 - Dauberschmidt, Ch. T1 - Corrosion monitoring of reinforced concrete structures:The DGZfP specification B12 Collaboration N2 - Corrosion monitoring of reinforced or prestressed concrete structures has becomeincreasingly important in recent years. Areas of application include componentsthat are no longer accessible after completion or where potential fieldmeasurements cannot be carried out due to existing coatings. Corrosion monitoringcan also be used to monitor the progress of corrosion in corroding systems, e.g. to prove the success of repair measures according to repair principle 8 in accordancewith EN 1504‐9 or repair method 8.3 in accordance with the DIBt repair guideline.It also could be used to prove the functionality of cathodic corrosion protectionsystems in accordance with ISO 12696. Despite the increasing importance ofcorrosion monitoring, no guidelines orrecommendations existed until 2018. Thisgap was closed by the English version of specification B12,“Corrosion Monitoringof Reinforced and Prestressed Concrete Structures,”of the German Society for Non‐Destructive Testing, which was published in 2021. This article introducesspecification B12 by explaining the basicmeasurement principles and illustratingthe potential of corrosion monitoring in new and existing buildings. KW - Corrosion KW - Monitoring PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-580982 DO - https://doi.org/10.1002/maco.202313934 SN - 0947-5117 SP - 1 EP - 9 PB - Wiley VHC-Verlag AN - OPUS4-58098 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ebell, Gino T1 - Dauerschwingversuche - H-Induzierte Spannungsrisskorrosion N2 - Wasserstoffinduzierte Spannungsrisskorrosion an hochfesten und hochempfindlichen Spannstählen führt an bestehenden Brückenbauwerken nach Jahren der Rissinitiierung zu Trag- und Standsicherheitsverlusten. Anhand des Beispiels der Brücke am Altstädter Bahnhof gibt es eine bauartbedingte Schadensinitiierung die über den gesamten Spannkanalquerschnitt zu Spannungsrisskorrosion führen kann. T2 - B1-Brücke Altstädter Bahnhof in Brandenburg an der Havel CY - Potsdam, Germany DA - 06.10.2021 KW - Korrosion KW - Spannstahl KW - Spannungsrisskorrosion PY - 2021 AN - OPUS4-53500 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF ED - Ebell, Gino T1 - Sammelmappe zum Sachkundelehrgang zur Durchführung von Potentialfeldmessungen 2023 N2 - Durch das alkalische Milieu des Porenwassers im Beton ist der Stahl normalerweise dauerhaft vor Korrosion geschützt. Unter ungünstigen Umgebungsbedingungen (Chlorideintrag, Karbonatisierung) kann die passive Deckschicht auf der Stahloberfläche zerstört werden. Der Korrosionsprozess ist initiiert. Die entstehenden Korrosionsprodukte werden zunächst vom Porengefüge des Betons aufgenommen, ohne dass es zu sichtbaren Schäden am Bauwerk führt. Im fortgeschrittenem Stadium der Korrosion können sich dann Risse und Abplatzungen bilden. Um notwendige Sanierungsmaßnahmen sowohl aus sicherheitstechnischen Gründen als auch aus wirtschaftlichen Erwägungen rechtzeitig einzuleiten, sind frühzeitige und weitestgehend zerstörungsfreie Prüfverfahren zur Ermittlung der aktuellen Korrosionswahrscheinlichkeit der Stahlbewehrung von großer Bedeutung. Deshalb finden Methoden und Verfahren zur laufenden bzw. regelmäßigen Korrosionsüberwachung von Stahlbetonbauwerken ständig größere Beachtung, sowohl im Bereich Forschung und Entwicklung als auch in der Praxis. Die elektrochemische Potentialfeldmessung ist ein etabliertes und weit verbreitetes Verfahren zur Beurteilung des Korrosionszustandes der Bewehrung in Stahlbetonbauwerken. Mit Hilfe dieses Verfahrens können Bereiche korrodierender Bewehrung zerstörungsfrei lokalisiert werden. In der Regel kommt diese Methode bei der Detektion von chloridinduzierter Korrosion zum Einsatz. Der Lehrgang vermittelt den Teilnehmenden in kompakter Form einen zusammenfassenden Überblick über die notwendigen Grundlagen zum Verständnis der Messmethode, der Vorbereitung und Durchführung der Messungen, der notwendigen Begleituntersuchungen sowie der Interpretation der gewonnenen Daten. Der erste Tag ist der theoretischen Ausbildung gewidmet, am zweiten Tag folgt dann die praktische Anwendung der Lerninhalte. Am dritten Tag folgt die Abnahme der praktischen und theoretischen Prüfung zur Erlangung des Sachkundenachweises. T2 - Sachkundelehrgang zur Durchführung von Potentialfeldmessungen CY - Berlin, Germany DA - 24.04.2023 KW - Potentialfeldmessung KW - Korrosion PY - 2023 SP - 1 EP - 85 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-57492 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ebeling, Anna A1 - Zekhnini, Khalid A1 - Ebell, Gino A1 - Pröfrock, Daniel T1 - Offshore Power-to-X and the marine environment-What we know and what we don't know N2 - To combat climate change the share of renewable energy production must increase drastically. Offshore energy production – offshore wind and power-to-X – are crucial to achieving climate targets. However, the impact of these offshore constructions – wind turbines and production platforms – on the marine environment remains unclear in many aspects. Potential sources of chemical emissions are corrosion protection systems, remobilization of contaminants from old sediments during construction, the brine of desalination plants and increased shipping for maintenance and transportation. In order to minimize the environmental impact of renewable energies, close monitoring is essential. The goal of this project is the development of a monitoring concept for an offshore power-to-X production platform. T2 - H2Mare PtX-Verbundtreffen CY - Hamburg, Germany DA - 16.04.2024 KW - Emission KW - Offshore KW - Wind energy KW - Sediment KW - Environment KW - Sea water PY - 2024 AN - OPUS4-59920 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ebell, Gino T1 - Atmospheric Corrosion - Sheltered Ventilated Conditions - An Opportunity for a Standardized Exposure site Rack N2 - To determine the corrosivity of atmospheric conditions, standardized metal sheets are exposed. After pickling, the loss of mass indicates the corrosivity of the atmospheric conditions. Under marine conditions, a sheltered opportunity will mirror the situation where e.g. chlorides could accumulate on the surface because they are protected from rain. Under these conditions, the corrosivity could be even higher than under free weather conditions. These sheltered conditions are necessary for a realistic service life prediction. T2 - Eurocorr 2024 CY - Paris, France DA - 01.09.2024 KW - Corrosion KW - Atmospheric corrosion KW - Korrosion PY - 2024 AN - OPUS4-60967 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Haacke, Nasrin T1 - Neubewertung von metallischen Dach- und Fassadenmaterialien unter Dauerhaftigkeits- und Umweltaspekten N2 - Der Vortrag stellt den aktuellen Stand des Forschungsprojekts RUNOFF vor. Dabei liegt der Fokus auf die Neubewertung der Dauerhaftigkeit von Zink und feuerverzinktem Stahl. Unter bewitterten Bedingungen erreichen beide Materialien stabile, karbonathaltige Deckschichten bereits nach einer Auslagerungszeit von zwei Monaten. In den parallel zu den Feldversuchen laufende Laborversuche werden aktuell der Einfluss dreier Faktoren (Ph-Wert, Winkel des Probenmaterials, Niederschlagsintensität) auf das Abschwemmverhalten von Zinkionen mithilfe eines an der BAM konstruierten Niederschlagsimulators untersucht. T2 - GAV Forschungskolloquium 2023 CY - Hannover, Germany DA - 16.10.2023 KW - Runoff KW - Dauerhaftigkeit KW - Zink KW - Feuerverzinkt PY - 2023 AN - OPUS4-58625 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ebell, Gino T1 - Detektion korrosionsaktiver Bereiche an Brückenbauwerken aus Stahlbeton mittels Potentialfeldmessung N2 - Durch das alkalische Porenwassermilieu wird Stahl im Beton durch Ausbildung einer Deckschicht vor Korrosion geschützt. Unter ungünstigen Umgebungsbedingungen (Karbonatisierung, Chlorideintrag) kann die passive Deckschicht auf der Stahloberfläche zerstört werden. Im weiteren Verlauf können sich durch Volumenexpansion der Korrosionsprodukte korrosionsbedingte Folgeschäden, wie Risse und Abplatzungen am Bauwerk ergeben. Um notwendige Sanierungsmaß-nahmen sind frühzeitige und weitgehend zerstörungsfrei ermittelte Informationen über das aktuelle Korrosionsverhalten der Stahlbewehrung von großer Bedeutung. Die Potentialfeldmessung ist ein etabliertes und weit verbreitetes Verfahren zur Beurteilung des Korrosionszustandes der Bewehrung in Stahlbetonbauwerken. Mit Hilfe dieses Verfahrens können Bereiche aktiv korrodierender Bewehrung zerstörungsfrei lokalisiert werden. In der Regel kommt diese Messmethode bei der Detektion chloridinduzierter Korrosion zum Einsatz. T2 - 4. Brückenkolloquium CY - Online meeting DA - 08.09.2020 KW - Korrosion KW - Potentialfeldmessung KW - Corrosion PY - 2020 AN - OPUS4-51219 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ebell, Gino T1 - Qualifikation von Prüfpersonal bei der ZfP im Bauwesen – Die neue DIN 4871 und ihre Folgen N2 - Die neu DIN 4871 regelt die Ausbildungsinhalt und die Anforderung an ZfP-Prüfpersonal für das Bauwesen. Die ZfP-Verfahren im Bauwesen sind größtenteils Bestandteil der Ausbildungsvarianten. Alle Verfahren und Prüfaufgaben für die man eine Qualifikation erwerben kann beziehen sich auf Stahl-bzw. Spannbetonbauwerke. Die Qualifikation von ZfP-Prüfpersonal ist eine Chance für das Bauwesen Prüfaufgaben mit gut ausgebildetem Personal bewerkstelligen zu können. T2 - 63. Aachener Baustofftage CY - Aachen, Germany DA - 14.11.2024 KW - ZfP KW - Zerstörungsfreie Prüfung KW - DIN 4871 PY - 2024 AN - OPUS4-61669 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Zekhnini, Khalid T1 - Corrosion at metallic offshore constructions – Bundesanstalt für Materialforschung und -prüfung (BAM) N2 - In the maritime context of offshore operation, corrosion, in combination with the materials used, poses a particular challenge to ensure safe operation over long indefinite periods and to minimise susceptibility to failure. Until today, only a few corrosion protection systems have proven themselves for the interaction of efficiency, installation, and maintenance in the offshore sector. In addition, available corrosion test methods sometimes have major deficits about conclusions of the durability. Therefore, there is more research and development needed. The flagship project H2Mare of the Federal Ministry of Education and Research aims to enable the production of green hydrogen and PtX products at high seas. Research is being driven forward by the partners in four individual projects, where BAM is involved in two. In PtX-Wind, major kinds of corrosion attacks at offshore constructions are characterized and investigated, and suitable corrosion protection measures determined. In TransferWind, attention focusses on transferring scientific results into standardization. This poster at the H2Mare Conference 2023 presents an overview of the investigation methods and contribution of the department “Corrosion and Corrosion Protection”. T2 - H2Mare Conference 2023 CY - Frankfurt/Main, Germany DA - 12.06.2023 KW - Atmospheric Corrosion KW - Sea Water KW - Corrosion Testing KW - Offshore KW - Laboratory Container KW - Corrosion protecting system PY - 2023 AN - OPUS4-57838 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Balscheit, Hagen T1 - Evaluation of pile tip buckling based on large scale tests N2 - Der Vortrag zum zugehörigen Konferenzbeitrag beschreibt eine groß angelegte Feldtestkampagne mit 16 Rammversuchen, um das Risiko des plastischen Versagens der Pfahlspitzen besser zu verstehen Ein numerisches Modell mit transientem Bodenkontakt zeigt eine gute Übereinstimmung mit den Testergebnissen. Parametervariationen verdeutlichen, wie empfindlich die Pfahlreaktion auf Imperfektionen und Randbedingungen ist. T2 - 5th International Symposium on Frontiers in Offshore Geotechnics (ISFOG) CY - Nantes, France DA - 09.06.2025 KW - Pile Tip Buckling KW - Monopile KW - Offshore Windenergy KW - Driving Refusal KW - Large Scale Test PY - 2025 AN - OPUS4-63391 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kaplan, F. A1 - Steinbock, O. A1 - Saloga, K. A1 - Ebell, Gino A1 - Schmidt, S. T1 - Überwachung der Brücke am Altstädter Bahnhof T1 - Monitoring of the bridge at the Altstadter Bahnhof in Brandenburg a. d. Havel N2 - Die B 1-Brücke am Altstädter Bahnhof war der wichtigste Verkehrsknotenpunkt in Brandenburg an der Havel. Im Dezember 2019 wurden die überführte Bundesstraße und die Straßenbahnlinie für den Verkehr gesperrt. Grund für die Sperrung war eine einsetzende Rissbildung in den Längsträgerstegen in Verbindung mit Hohlstellen, die letztlich auf gerissene Spanndrähte zurückgeführt werden. Um eine Sperrung der hoch frequentierten unterführten Verkehrswege zu verhindern, wurde ein umfangreiches Überwachungskonzept erforderlich. Wesentlicher Bestandteil dieses Konzepts war ein auf der Schallemissionsanalyse basierendes Monitoringsystem, mit dessen Hilfe Spanndrahtbrüche aufgezeichnet und lokalisiert werden konnten. Auf Grundlage der so gewonnenen Ergebnisse konnten Schwerpunkte für die Bauwerksprüfung abgeleitet werden. In diesem Bericht werden die gewonnenen Erkenntnisse zum messtechnisch erfassten Schadensfortschritt und den damit verbundenen visuell festgestellten Schäden beschrieben. Dabei werden die Besonderheit des verbauten konzentrierten Spannglieds (Spannblockverfahren nach TGL 173-33) und des Spannstahls in Bezug auf die Schadensbilder dargestellt. Die gewonnenen Erkenntnisse sollten bei der Beurteilung anderer Bauwerke mit vergleichbarer Bauart berücksichtigt werden. KW - Korrosion KW - Spannstahl KW - Spannungsrisskorrosion PY - 2022 DO - https://doi.org/10.1002/bate.202200008 SN - 0932-8351 VL - 99 IS - 3 SP - 222 EP - 230 PB - Ernst & Sohn AN - OPUS4-54485 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Haacke, Nasrin T1 - Forschungsprojekt Runoff: "Neubewertung der Dauerhaftigkeit von Dach und Fassadenmaterialien und des Eintrags von Schwermetall Ionen in die Umwelt hervorgerufen durch Runoff“ N2 - Der Vortrag stellt das Forschungsvorhaben RUNOFF vor, welcher auf der zweitägigen Veranstaltung „24. Projekttage der Bauforschung“ gehalten wurde. Die Präsentation erläutert zunächst die Bedeutung der Abschwemmung von Metallionen für die Bauindustrie und Umwelt. Dabei werden Faktoren, welche den Schadstofftransport im urbanen Raum begünstigen sowie Stadtentwässerungstypen vorgestellt. Anschließend folgen Folien zum wissenschaftlichen Hintergrund zur Ausbildung von Deckschichten, aktuellen Wissensstand sowie Lücken in der Korrosionsforschung von metallenen Werkstoffen unter atmosphärischen Bedingungen. Nach einer kurzen Übersicht zu den Hauptzielen des Forschungsvorhabens wurde detaillierter auf die Versuchsdurchführung sowie fünf der acht Arbeitspakete mitsamt Zwischenergebnissen eingegangen. T2 - 24. Projekttage der Bauforschung CY - Bonn, Germany DA - 13.06.2023 KW - Runoff KW - Korrosion KW - Kupfer KW - Zink PY - 2023 AN - OPUS4-57741 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wallau, Wilma A1 - Recknagel, Christoph A1 - Smales, Glen Jacob T1 - Structural silicone sealants after exposure to laboratory test for durability assessment N2 - During the service life of structural sealant glazing (SSG) facades, the loadbearing capacity of the silicone bonds needs to be guaranteed. Laboratory Tests can assess the durability of SSG-systems based on mechanical characteristics of the bond after simultaneous exposure to both climatic and mechanical loads. This article studies how the material characteristics of two common structural sealants are affected by laboratory and field exposure. Dynamic mechanical Analysis (DMA) confirms a reduction in the dynamic modulus of exposed Silicone samples. Results from thermogravimetric analysis, Fourier-transform infrared spectroscopy, differential scanning calorimetry, and small-angle X-ray scattering/wide-angle X-ray scattering show differences between the two sealants and indicate no/minor changes in the composition and morphology of the laboratory and field exposed sealants. Mechanical characterization methods, such as DMA, and tensile and shear testing of the structural bond, are shown to be sensitive toward the combined climatic and mechanical loadings, and are hence suitable for studying degradation mechanisms of structural sealants. KW - Aging KW - Analytical methods KW - Fatigue KW - Silicone elastomer KW - Structural sealant glazing PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-527217 DO - https://doi.org/10.1002/app.50881 VL - 138 IS - 35 SP - 50881 PB - Wiley AN - OPUS4-52721 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Maack, Stefan A1 - Torrent, R. A1 - Ebell, Gino A1 - Völker, Tobias A1 - Küttenbaum, Stefan T1 - Testing to reassess – Corrosion activity assessment based on NDT using a prestressed concrete bridge as case-study N2 - Corrosion of concrete reinforcement is one of the major damage mechanisms affecting both the load-bearing capacity and the serviceability of re-inforced concrete structures significantly. When externally discernible damages are observed during visual inspections on the structure, the extent of the damage inside the concrete is often already significant. Corrosion caused by carbonation often leads to severe discoloration of the surface or even large-area spalling of the concrete cover. In contrast, chloride-induced corrosion is usually difficult to observe visually but can cause much more serious damage in less time. The effect occurs locally and can lead to weakening of the cross-section of the reinforce-ment. This, in turn, can cause sudden structural collapses without prior notice. In the meanwhile, various non-destructive and minimally invasive testing methods are available to evaluate the resistance to penetration of corrosion-pro-moting pollutants and to detect active corrosion. In this paper, a bridge crossing the river Regen is used as a case-study to demonstrate how the information ob-tained applying different testing methods can be combined and evaluated in the context of structural reassessments. Both the results of the permeability testing and the electrical resistance measurement are considered, as well as active corro-sion areas are localized using the half-cell potential mapping combined with the concrete cover measurement with the eddy current method and ground penetrat-ing radar. The results are evaluated using drill cores and in addition laser-induced breakdown spectroscopy was applied to obtain information about possible chlo-ride ion transport into the concrete. T2 - EUROSTRUCT 2021 – 1ST conference of the european association on quality control of bridges and structures - Eurostruct CY - Padova, Italy DA - 30.08.2021 KW - Nondestructive testing KW - Corrosion KW - Bridge KW - Durability assessment KW - Civil engineering PY - 2022 SN - 978-3-030-91876-7 SP - 1 EP - 9 PB - Springer International Publishing AN - OPUS4-54006 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Seifert, Lando T1 - Exposé on the PhD-thesis: Initiation of stress corrosion cracking in prestressing steels N2 - The exposé is a mandatory part of the doctoral process at TUM and should outline the topic of the thesis and the future research focus. Ideally, the exposé forms the basis for the subsequent dissertation. The candidates topic is about hydrogen-induced stress corrosion cracking (HiSCC) of prestressing steels, which is a significant concern in civil engineering, particularly for prestressed concrete roofs and bridges. The susceptibility of prestressing steels to HiSCC is mainly influenced by manufacturing processes and the chemical composition, while the ability to hydrogen charging is influenced by the environmental and surface conditions. To know about the real nature of susceptibility of the prestressing steel might be an important puzzle piece to contribute to safe prestressed concrete structures in the future. The material susceptibility of prestressing steels toward HiSCC is a topic which must be studied independently of the environmental conditions. This cumulative dissertation will focus on the most important aspects of material properties that play a role in the initiation point of HiSCC. KW - Prestressing Steels KW - Hydrogen-induced stress corrosion cracking KW - Stress corrosion cracking KW - Brittle Fracture PY - 2024 SP - 1 EP - 8 CY - Graduate Center, TUM School of Engineering and Design, Technische Universität München AN - OPUS4-62051 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Ebell, Gino A1 - Bösche, T. A1 - Steinbock, O. T1 - Rückschlüsse aus den Schadensbildern N2 - Wasserstoffinduzierte Spannungsrisskorrosion an hochfesten und hochempfindlichen Spannstählen führt an bestehenden Brückenbauwerken nach Jahren der Rissinitiierung zu Trag- und Standsicherheitsverlusten. Anhand des Beispiels der Brücke am Altstädter Bahnhof gibt es eine bauartbedingte Schadensinitiierung die über den gesamten Spannkanalquerschnitt zu Spannungsrisskorrosion führen kann. KW - Korrosion KW - Spannstahl KW - Spannungsrisskorrosion PY - 2021 SP - 85 EP - 87 PB - Landesbetrieb Straßenwesen Brandenburg CY - Hoppegarten AN - OPUS4-53506 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ebell, Gino A1 - Burkert, Andreas T1 - Standortabhängige Dauerhaftigkeitsbetrachtungen von Zink unter atmosphärischer Korrosion N2 - In maritimer Exposition können Zinkbauteile Nutzungsdauern von 50 Jahren erreichen. Dabei werden Expositionen mit Spritzwasserbelastung durch Meerwasser nicht betrachtet. Normative Betrachtungen und Korrosionsprognosen basierend auf Einjahreswerten liefern hier grundlegend falsche Ergbnisse, da sie eine signifikant höhere Belastung der Atmosphäre mit SO2 voraussetzen. T2 - GAV-Forschungsbeiratssitzung CY - Darmstadt, Germany DA - 17.05.2022 KW - Korrosion KW - Zink PY - 2023 AN - OPUS4-57631 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - RPRT A1 - Ebell, Gino A1 - Fischer, O. A1 - Mensinger, M. T1 - Neuartiger Vergussstoß mit ultrahochfestem, faserverstärktem Beton für feuerverzinkte integrale Rahmenbrücken in Verbundbauweise N2 - Neuartige Technik zur Erstellung Einfeld-Brückenbauwerken aus feuerverzinkten Stahlbauteilen. Ziel des Vorhabens ist einen Vergussknoten zu konzipieren der zwei Brückensegmente fügt ohne jegliche nachträgliche Schraub- oder Schweißverbindung. Realisiert wurde dies mit ultrahochfestem Vergussbeton. KW - Feuerverzinken KW - Korrosion KW - Brücke PY - 2023 UR - https://www.gav-verzinken.de/forschung/wissenspool SP - 1 EP - 23 AN - OPUS4-57504 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ebell, Gino T1 - Neue Erkenntnisse zu wasserstoffinduzierten Spannungsrissen infolge korrosiver Belastung hochempfindlicher Spannstähle in Spannblockverfahren nach TGL 173-33 N2 - Brückenbauwerke, die im Spannblockverfahren hergestellt wurden, können bauartbedingt wasserstoffinduzierte Spannungsrisse über den gesamten Querschnitt eines Spannkanals aufweisen. Das Risswachstum kann infolge dynamischer Beanspruchung über die Nutzungsdauer fortschreiten und zu Spanndrahtbrüchen führen. T2 - Mittwochscafé SGS CY - Online meeting DA - 30.10.2024 KW - Korrosion KW - Spannstahl KW - Spannungsrisskorrosion KW - Wasserstoff PY - 2024 AN - OPUS4-61494 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ebell, Gino T1 - Innovative Prüfverfahren für die Korrosionsprüfung von Beton- und Spannstähle N2 - Neue Materialien bedürfen je nach Fragestellung angepasste Prüfverfahren um die Anwendung dieser in der Praxis in Gänze sicherstellen zu können. Hierzu hat die BAM ein neues Prüfverfahren entwickelt und bestehende Prüfverfahren für neue Fragestellungen zu bestehenden Materialien angepasst. T2 - 63. Forschungskolloquium der BAM und des dafstb CY - Berlin, Germany DA - 16.10.2024 KW - Corrosion KW - Korrosion KW - Spannungsrisskorrosion KW - Wasserstoff PY - 2024 AN - OPUS4-61371 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ebell, Gino T1 - Spannbetonbauwerke - Von der Initiierung zum Schaden N2 - Wasserstoffinduzierte Spannungsrisskorrosion an hochfesten und hochempfindlichen Spannstählen führt an bestehenden Brückenbauwerken nach Jahren der Rissinitiierung zu Trag- und Standsicherheitsverlusten. Anhand des Beispiels der Brücke am Altstädter Bahnhof gibt es eine bauartbedingte Schadensinitiierung die über den gesamten Spannkanalquerschnitt zu Spannungsrisskorrosion führen kann. T2 - AK-Sitzung Korrosionsschutz im konstruktiven Ingenieurbau CY - Online meeting DA - 12.05.2022 KW - Spannungsrisskorrosion KW - Korrosion PY - 2022 AN - OPUS4-54874 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ebell, Gino T1 - Neue Erkenntnisse zu wasserstoffinduzierten Spannungsrissen infolge korrosiver Belastung hochempfindlicher Spannstähle in Spannblockverfahren nach TGL 173-33 N2 - Brückenbauwerke, die im Spannblockverfahren hergestellt wurden, können bauartbedingt wasserstoffinduzierte Spannungsrisse über den gesamten Querschnitt eines Spannkanals aufweisen. Das Risswachstum kann infolge dynamischer Beanspruchung über die Nutzungsdauer fortschreiten und zu Spanndrahtbrüchen führen. T2 - 5. Brückenkoloquium CY - Ostfildern, Germany DA - 06.09.2022 KW - Korrosion KW - Spannungsrisskorrosion KW - Brücke KW - Wasserstoff PY - 2022 AN - OPUS4-55663 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ebell, Gino T1 - Standortabhängige "Dauerhaftigkeitsprognose mittels Langzeitauslagerungsversuchen" von Zink N2 - In maritimer Exposition können Zinkbauteile Nutzungsdauern von 50 Jahren erreichen. Dabei werden Expositionen mit Spritzwasserbelastung durch Meerwasser nicht betrachtet. Normative Betrachtungen und Korrosionsprognosen basierend auf Einjahreswerten liefern hier grundlegend falsche Ergebnisse, da sie eine signifikant höhere Belastung der Atmosphäre mit SO2 voraussetzen. T2 - Künstliche Intelligenz vs. Maritime Korrosion - Where do we go? CY - Hamburg, Germany DA - 11.07.2023 KW - Korrosion KW - Korrosivität PY - 2023 AN - OPUS4-57911 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ebell, Gino T1 - Mögliche Fehlerquellen in der Praxis N2 - Die Potentialfeldmessung ist ein etabliertes und weit verbreitetes Verfahren zur Beurteilung des Korrosionszustandes der Bewehrung in Stahlbetonbauwerken. Mit Hilfe dieses Verfahrens können Bereiche aktiv korrodierender Bewehrung zerstörungsfrei lokalisiert werden. In der Regel kommt diese Messmethode bei der Detektion chloridinduzierter Korrosion zum Einsatz. Bei der Durchführung dieser Messung gibt es jedoch messtechnikspezifische Fehlerquellen und äußere Einflüsse aus dem zu untersuchenden Bauwerk die eine Interpretation der Messergebnisse signifikant beeinflussen können. T2 - Sachkundelehrgang zur Durchführung von Potentialfeldmessungen 2022 CY - Baruth/Mark, Germany DA - 16.05.2022 KW - Korrosion KW - Potentialfeldmessung PY - 2022 AN - OPUS4-54872 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schneider, Ronald T1 - Probabilistic approaches to the design and assessment of offshore foundations considering spatially varying site conditions N2 - In this presentation, we discuss the potential of probabilistic approaches to the design and assessment of offshore foundations. The potential is demonstrated in a numerical example considering a laterally loaded monopile. As an outlook, we present a concept for managing the risk associated with installing large monopiles. T2 - 3rd International Conference on Structural Integrity for Offshore Energy Industry (SI 2021) CY - Online meeting DA - 15.11.2021 KW - Offhore KW - Foundations KW - Probabilistic KW - Design KW - Assessment PY - 2021 AN - OPUS4-53748 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Feistkorn, S. A1 - Algernon, D. A1 - Arndt, R. A1 - Ebell, Gino A1 - Friese, M. A1 - Grosse, C. U. A1 - Holstein, R. A1 - Niederleithiger, Ernst A1 - Schickert, M. A1 - Schulze, S. A1 - Taffe, A. A1 - Walther, A. A1 - Wolf, J. A1 - Zoega, A. A1 - Zwanzig, M. T1 - Introduction to DIN 4871: Qualification of NDT Personnel in Civil Engineering (NDT‐CE) N2 - Recently, non-destructive testing in civil engineering (NDT-CE), in particular of concrete components, has successfully mastered the leap from research to practice. Several methods have been established for field inspections to determine the concrete cover of reinforcement or to estimate the compressive strength as well as other parameters related to the concrete material. In addition, the application of non-destructive testing is indispensable, if information about the inner structure - such as the location of rebars and tendon ducts or the damage-related condition assessment to detect grouting defects, honeycombs, delamination, or corrosion - is required. Besides the selection of a suitable NDT method and an appropriate inspection system, the reliability of the results depends largely on the person who applies the non-destructive inspection technique and evaluates the inspection results. To ensure a high quality of non-destructive concrete evaluation as well as to keep the uncertainty caused by the inspection personnel to a minimum, structured, consistent, and regulated theoretical as well as practical training of inspection personnel is essential. To close this gap, the subcommittee of education and training (UA-A) within the committee for NDT-CE of the German Society for Non-Destructive Testing (DGZfP) has been reactivated in 2018 to establish uniform training standards for non-destructive concrete inspections in the long term. The subcommittee consists of scientists, practitioners, authorities, and clients. So far, the national standard DIN 4871 “Non-destructive testing - Qualification of NDT personnel in Civil Engineering (NDT-CE)” was developed. This standard considers the civil-industry-specifics, for example, that standards for NDT of concrete, as well as related product standards with a few exceptions, still do not exist at the moment. Within this presentation, the concept, the connection to ISO 9712 and other standards as well as an overview of the recently developed German standard DIN 4871 will be presented. T2 - NDT-CE 2022 CY - Zurich, Switzerland DA - 16.08.2022 KW - Non-destrucive testing KW - Civil engineering PY - 2022 AN - OPUS4-55526 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Geißler, Peter T1 - Compaction grouting to improve the pile bearing capacity in non-cohesive soil N2 - The increasing use of renewable energies leads to a constant search for optimised foundation concepts aiming to reduce the costs for offshore wind turbines. In an ongoing research project, we are developing a design approach for typical offshore driven piles based on the application of injections by compaction grouting directly at the pile shaft. Compaction grouting as a ground improvement technique has been used widely as a countermeasure against liquefaction, settlement and low bearing capacity of soil under new or already existing structures. It is performed by forcing highly viscous grout into the soil to displace and compact the surrounding soil without fracturing or penetrating it. Regarding this injection method, this paper gives a brief overview about general aspects such as appropriate soil characteristics and grouting parameters, grouting equipment and fields of application particularly in the offshore sector. This indicates the ability of our optimisation concept to provide an economic alternative to larger pile dimensions and a retrofitting technique, which is available during the entire lifetime of the foundation and can be deployed only in case of necessity (e.g. excessive deformations or insufficient structural stiffness after an extreme load event). Besides the material feasibility and the constructive realisation of this improvement measure, the development of a corresponding verification concept is crucial in order to ensure the safety and durability of the retrofitted offshore piles. Here we will examine various verification concepts with their respective limitations in the framework of the limit state design. Furthermore, we will present the experimental findings from field tests in sand indicating the advantages of several local injections by compaction grouting for the enhancement of the load bearing behaviour of pile foundations. The test results were also used to validate a numerical model, developed with the finite element program PLAXIS, aiming to predict the expected bearing capacity for different injection scenarios (e.g. grout volume, location of injection points) along a pile shaft. T2 - Twenty-ninth International Ocean and Polar Engineering Conference CY - Honolulu, HI, USA DA - 16.06.2019 KW - Offshore Pile Foundation KW - Compaction Grouting KW - Grout KW - Injection Sequence KW - Tensile Capacity PY - 2019 AN - OPUS4-48504 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Gluth, Gregor A1 - Sittner, Jonathan A1 - Asante, Bright A1 - Nikoonasab, Ali A1 - Ebell, Gino T1 - 63. DAfStb-Forschungskolloquium in der BAM - Themenblock 1: Chemie der Bindemittel N2 - Aus Gründen des Klimaschutzes werden in den kommenden Jahren mehr Zemente mit verringertem Klinkerfaktor und alternative Bindemittel (klimafreundliche Bindemittel) zum Einsatz kommen. Für ihre sichere und zuverlässige Verwendung ist ein umfangreiches Verständnis der Einflüsse auf die Dauerhaftigkeit der aus ihnen hergestellten Betone notwendig. In jüngerer Zeit sind hierzu insbesondere von Technischen Komitees in RILEM und in der EFC neue Erkenntnisse gewonnen worden, die im Rahmen des 63. DAfStb-Forschungskolloquiums an der BAM (Tagungsband: DOI 10.26272/opus4-61338) im Zusammenhang mit den Beiträgen der BAM zu diesen Ergebnissen vorgestellt wurden. T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM Green Intelligent Building CY - Berlin, Germany DA - 16.10.2024 KW - Zement KW - Bindemittel KW - Dauerhaftigkeit KW - Beton PY - 2025 SN - 0005-9846 VL - 75 IS - 4 SP - 129 EP - 131 PB - concrete content UG CY - Schermbeck AN - OPUS4-63066 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ebell, Gino A1 - Burkert, Andreas T1 - Prestressed concrete structures with concentrated tendons - Structural damage due to hydrogen-induced stress corrosion cracking N2 - Hydrogen-induced stress corrosion cracking (HSCC) is well known, and highly sensitive pre-stressing steels are normally not available on the market. But in the case of existing structures, it could be necessary to ensure their safety through special kinds of investigations. Those kinds of investigations are often not applicable in a non-destructive way. Therefore, a once in a lifetime project was initiated. In the course of the deconstruction of the "Bridge of the 20th anniversary of the GDR" at the Altstädter Bahnhof in Brandenburg a. d. Havel, new information on the initiation of hydrogen-induced stress cracks could obtained. The initial observation to do several investigations at this bridge are several meters long longitudinal cracks in the concrete web of the box girder above and below the tension duct. The BAM was commissioned by the Brandenburg State Road Administration to participate in a corresponding joint project which is financed by the Federal Ministry for Digital and Transport. The added value of the new information gained in this project goes beyond the specific structure. It describes unexpected new damage patterns that can be transferred to other structures with concentrated tendons (tendon block method and Baur-Leonhardt method) and were previously unknown in this form. These should be made known to other developers to enable them to initiate any necessary actions. One of the major results is, the wire breaks observed at this bridge can be attributed to cracking as a result of HSCC and subsequent crack growth until breakage, due to cyclic loading from traffic and alternating restraint stresses. The probable trigger here was crevice corrosion processes at the contact points of the wires to the spacer plates in superposition with high tensile stresses due to prestressing after or with in grouting the duct. Tension wire breaks, which may have occurred before grouting and during prestressing, were not detected. The unfavorable gap situation at the spacer plates occurs over the entire cross-section of the prestressing channel and can thus affect each individual prestressing wire. Losses in the load-bearing capacity of the prestressed concrete structure can then be the result. A disadvantage of the prestressing block method in this respect is that a large number of individual wires can be affected at the same time (theoretically all wires), which can reduce the prestressing effect of the concentrated tendon accordingly. With the usual use of only one tendon per web, the possibility of load transfer to other tendons is thus not given (lack of redundancy). T2 - 4rd International Congress on Materials & Structural Stability CY - Rabat, Morocco DA - 08.03.2023 KW - Corrosion KW - HSCC KW - Wasserstoff KW - Spannungsrisskorrosion PY - 2023 AN - OPUS4-57158 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Simon, Patrick A1 - Schneider, Ronald A1 - Baeßler, Matthias A1 - Morgenthal, Guido T1 - Parallelized adaptive Bayesian updating with structural reliability methods for inference of large engineering models N2 - The reassessment of engineering structures, such as bridges, now increasingly involve the integration of models with realworld data. This integration aims to achieve accurate ‘as-is’ analysis within a digital twin framework. Bayesian model updating combines prior knowledge and data with models to enhance the modelling accuracy while consistently handling uncertainties. When updating large engineering models, numerical methods for Bayesian analysis present significant computational challenges due to the need for a substantial number of likelihood evaluations. The novelty of this contribution is to parallelize adaptive Bayesian Updating with Structural reliability methods combined with subset simulation (aBUS) to improve its computational efficiency. To demonstrate the efficiency and practical applicability of the proposed approach, we present a case study on the Maintalbrücke Gemünden, a large railway bridge. We leverage modal property data to update a linear-elastic dynamic structural model of the bridge. The parallelized aBUS approach significantly reduces computational time, making Bayesian updating of large engineering models feasible within reasonable timeframes. The improved efficiency allows for a wider implementation of Bayesian model updating in structural health monitoring and maintenance decision support systems. KW - Bayesian model updating KW - Bayesian updating with structural reliability methods KW - Structural health monitoring KW - Parallelization KW - Modal analysis KW - Railway bridge PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-633686 DO - https://doi.org/10.1177/13694332251346848 SN - 1369-4332 SN - 2048-4011 SP - 1 EP - 26 PB - Sage AN - OPUS4-63368 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ebell, Gino T1 - Merkblatt B03 der DGZfP Ausgabe April 2021 N2 - Durch das alkalische Porenwassermilieu ist Stahl im Beton vor Korrosion geschützt. Unter ungünstigen Umgebungsbedingungen (Karbonatisierung, Chlorideintrag) kann die passive Deckschicht auf der Stahloberfläche zerstört werden. Im weiteren Verlauf können sich korrosionsbedingte Folgeschäden, wie Risse und Abplatzungen am Bauwerk ergeben. Um notwendige Sanierungsmaßnahmen sind frühzeitige und weitgehend zerstörungsfrei ermittelte Informationen über das aktuelle Korrosionsverhalten der Stahlbewehrung von großer Bedeutung. Die Potentialfeldmessung ist ein etabliertes und weit verbreitetes Verfahren zur Beurteilung des Korrosionszustandes der Bewehrung in Stahlbetonbauwerken. Mit Hilfe dieses Verfahrens können Bereiche aktiv korrodierender Bewehrung zerstörungsfrei lokalisiert werden. In der Regel kommt diese Messmethode bei der Detektion chloridinduzierter Korrosion zum Einsatz. Wie und unter welchen Randbedingungen dieses Messverfahren zielführend eingesetzt werden kann, ist im Merkblatt B 03 der dgzfp erörtert. T2 - Sachkundelehrgang Potentialfeldmessung CY - Aachen, Germany DA - 25.06.2024 KW - Korrosion KW - Potentialfeldmessung PY - 2024 AN - OPUS4-60586 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ebell, Gino T1 - Potentialfeldmessung in Theorie und Praxis N2 - Durch das alkalische Porenwassermilieu ist Stahl im Beton vor Korrosion geschützt. Unter ungünstigen Umgebungsbedingungen (Karbonatisierung, Chlorideintrag) kann die passive Deckschicht auf der Stahloberfläche zerstört werden. Im weiteren Verlauf können sich korrosionsbedingte Folgeschäden, wie Risse und Abplatzungen am Bauwerk ergeben. Um notwendige Sanierungsmaßnahmen sind frühzeitige und weitgehend zerstörungsfrei ermittelte Informationen über das aktuelle Korrosionsverhalten der Stahlbewehrung von großer Bedeutung. Die Potentialfeldmessung ist ein etabliertes und weit verbreitetes Verfahren zur Beurteilung des Korrosionszustandes der Bewehrung in Stahlbetonbauwerken. Mit Hilfe dieses Verfahrens können Bereiche aktiv korrodierender Bewehrung zerstörungsfrei lokalisiert werden. In der Regel kommt diese Messmethode bei der Detektion chloridinduzierter Korrosion zum Einsatz. T2 - Vorlesung TU Berlin CY - Online meeting DA - 10.06.2020 KW - Korrosion KW - Corrosion KW - Potentialfeldmessung PY - 2020 AN - OPUS4-50905 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Haacke, Nasrin T1 - Design and construction of a rainfall simulator to test metal runoff at atmospheric conditions N2 - A rainfall simulator was presented as an environmental assessment tool to quantify wash-off concentrations from metallic materials. It is part of the RUNOFF-project, which studies and re-assesses the durability of roofing and facade materials under current atmospheric conditions in Germany. Studying building materials is important as they have a significant impact on achieving a variety of goals and targets within the sustainable developments goals (SDGs). The durability of materials is essential to reach sustainability. However, the durability of metallic materials is strongly depended on climate conditions, which have changed as a result of technical measures in industry, climate change and increasing urbanisation. In Germany at least, the data base is not up-to-date leading to prediction models regarding corrosion resistance and durability of metallic materials which can no longer be trusted and therefore need to be re-assessed and updated. Also, not only the demand for sustainable but also environmentally friendly building materials has increased dramatically. A number of construction materials produce chemical hazards, and therefore have negative impacts on water quality, soils health and ecosystems. To limit these impacts, environmental assessment methods and tools are needed to measure and quantify the inputs and outputs of building materials throughout their lifetime. T2 - EUROCORR 2023 CY - Brussels, Belgium DA - 27.08.2023 KW - Rainfall simulator KW - Runoff KW - Atmospheric conditions KW - Laboratory experiments PY - 2023 AN - OPUS4-58152 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schwarz, W. A1 - Wilsch, Gerd A1 - Katsumi, N. A1 - Ebell, Gino A1 - Völker, Tobias T1 - Ion distribution in concrete overlay, mapped by laser induced breakdown spectroscopy (LIBS), modified by an embedded zinc anode N2 - Galvanic corrosion protection by embedded zinc anodes is an accepted technique for the corrosion protection of reinforcing steel in concrete. Galvanic currents flow between the zinc anode and the steel reinforcement due to the potential difference that is in the range of a few hundred mV. The ion distribution was studied on two steel reinforced concrete specimens admixed with 3 wt.% chloride/wt. cement and galvanically protected by a surface applied EZ-anode. On both specimens, a zinc anode was embedded and glued to the concrete surface by a geo-polymer-based chloride-free binder. At one specimen, the EZ-anode was operated for 2,5 years, the EZ-anode at the other specimen was not electrically connected to the reinforcement, this specimen serves as a reference. Both specimens have been stored under identical conditions. The ion distribution between the anode (EZ-anode) and cathode (steel reinforcement) was studied by laser-induced breakdown spectroscopy (LIBS) after 7 months, 12 months, and 2,5 years. Results of the LIBS studies on the specimen with activated EZ-anode after 7 months, 12 months, and 2,5 years and of the reference specimen after 2,5 years are reported. Results show that diffusion of ions contributes to the changes in the ion distribution but migration, especially of chlorides towards the EZ-anode is significant despite the weak electric field – several hundred millivolts - generated by the galvanic current. Results show that chloride ions accumulate near the zinc-anode as in water-insoluble zinc-hydroxy chlorides - Simonkolleit. T2 - ICCRRR 2022 CY - Capetown, South Africa DA - 03.10.2022 KW - Korrosion KW - Corrosion KW - LIBS KW - Zinc PY - 2022 AN - OPUS4-55948 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ebell, Gino A1 - Burkert, Andreas T1 - Standortabhängige Dauerhaftigkeitsbetrachtungen von Zink unter atmosphärischer Korrosion N2 - In maritimer Exposition können Zinkbauteile Nutzungsdauern von 50 Jahren erreichen. Dabei werden Expositionen mit Spritzwasserbelastung durch Meerwasser nicht betrachtet. Normative Betrachtungen und Korrosionsprognosen basierend auf Einjahreswerten liefern hier grundlegend falsche Ergebnisse, da sie eine signifikant höhere Belastung der Atmosphäre mit SO2 voraussetzen. T2 - AK-Sitzung Atmosphärische Korrosion CY - Berlin, Germany DA - 24.10.2023 KW - Korrosion KW - Deckschichtbildung KW - Zink PY - 2023 AN - OPUS4-59342 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ebell, Gino T1 - Prestressed Concrete Structures with Concentrated Tendons - Structural Damage due to Hydrogen-Induced Stress Corrosion Cracking N2 - In the course of the deconstruction of the "Bridge of the 20th anniversary of the GDR" at the Altstädter Bahnhof in Brandenburg a. d. Havel, new information on the initiation of hydrogen-induced stress cracks was obtained. BAM was commissioned by the Brandenburg State Road Administration to participate in a corresponding joint project which is financed by the Federal Ministry for Digital and Transport. The added value of the new information gained in this project goes beyond the specific structure. It describes unexpected new damage patterns that can be transferred to other structures with concentrated tendons (tendon block method and Baur-Leonhardt method) and were previously unknown in this form. These should be made known to other developers to enable them to initiate any necessary actions. T2 - Eurocorr 2022 CY - Berlin, Gemany DA - 29.08.2022 KW - Korrosion KW - Corrosion KW - Hydrogen KW - Stress Cracking PY - 2022 AN - OPUS4-55613 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Seifert, Lando T1 - Promotionsvorhaben: Initiierung von Spannungsrisskorrosion in hochfesten Spannstählen N2 - This talk is a about the PhD-topic “initiation of hydrogen-induced stress corrosion cracking of prestressing steels (HiSCC)”, which is a major concern in civil engineering, particularly for prestressed concrete roofs and bridges. The susceptibility of prestressing steels to HiSCC is mainly influenced by manufacturing processes and the chemical composition, while the ability to hydrogen charging is by the environmental and surface conditions. To know about the real nature of susceptibility of the prestressing steel might be an important puzzle piece to contribute to safe prestressed concrete structures in the future. The material susceptibility of prestressing steels toward HiSCC is a topic which must be studied independently of the environmental conditions. This cumulative dissertation will focus on the most important aspects of material properties that play a role in the initiation point of HiSCC. T2 - Instituts-Symposium der TU München "Spannstahltage TUM" CY - Garching bei München, Germany DA - 14.11.2024 KW - Prestressing Steels KW - ISO 15630-3 KW - Hydrogen-induced Stress Corrosion Cracking KW - Brittle Fracture PY - 2024 AN - OPUS4-62052 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ebell, Gino T1 - Potential Mapping - What could we measure and what should we able to detect – guideline B03 of DGZfP N2 - “Electrochemical potential mapping according to guideline B3 of DGZfP (German Society for Non-Destructive Testing) is a recognized technique for the localization of corroding reinforcing steels. Areas of corroding reinforcement steel can be located in a non-destructive manner by means of this procedure. Half‐cell potential measurements are used in order to detect chloride‐induced corrosion. However, it is not recommended in order to assess the risk of carbonation‐induced corrosion. For this purpose, determining the carbonation depth and the concrete cover appears more appropriate. The content of this specification exclusively refers to the application of mobile, local variable reference electrodes, which are only placed on the concrete surface while measuring. The technique distinguishes itself thereby from the range of corrosion monitoring systems with stationary installed reference electrodes and sensor systems, respectively, whereby it is possible to continuously track measurements within the area of the installed electrodes. However, these methods are not dealt with in this specification.” T2 - NDT-CE 2022 CY - Zurich, Switzerland DA - 16.08.2022 KW - Korrosion KW - Potentialfeldmessung KW - Corrosion KW - Half-cell potential KW - Potential mapping PY - 2022 AN - OPUS4-55524 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ebell, Gino A1 - Lehmann, Jens A1 - Burkert, Andreas T1 - Weathring camopaigns to determine corrosivity on offshore wind turbines N2 - ISO 9223 standard for the classification of corrosivity in atmospheres is based on the mass loss of standard samples. We are concerned with the question of which corrosivity categories for Fe-sheets can be found at an offshore wind turbine and where they are comparable with our offshore locations. The preliminary results indicate that the extreme corrosivity of class CX is only given in splash water-affected exposure, which is not a real atmospheric exposure condition. The results of the exposure at the SP show that the corrosivity category changes into C4, only a few meters above the splash water zone. Compared to the marine environments at Helgoland or OSS-Platform, the corrosivity is higher. The offshore environment is not as corrosive as originally expected, no atmospheric corrosion attack could be determined that would form the corrosivity category C5. T2 - Eurocorr 2024 CY - Paris, France DA - 01.09.2024 KW - Korrosion KW - Corrosion PY - 2024 AN - OPUS4-60973 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Zekhnini, Khalid A1 - Babutzka, Martin A1 - Seifert, Lando A1 - Burkert, Andreas A1 - Ebell, Gino A1 - Bäßler, Ralph T1 - Investigation of corrosion behavior of S355 steel in artificial seawater and sediment N2 - The safe operation of offshore wind turbines places high demands on corrosion protection. This is particularly the case about the planned future extension of the service life beyond 25 years. The highly corrosive environment towards metallic materials leads to a loss of material thickness of the tower structure and thus to a deterioration of mechanical properties. This can be counteracted by corrosion protection measures adapted to the respective load case, such as organic coatings and cathodic corrosion protection (CCP). Much research has already been done in this area about inhibiting the corrosion process and there are regulations and guidelines that specify requirements for corrosion protection to achieve the required service lives. However, gaps exist regarding free corrosion. This plays a greater role especially for time intervals during the installation of the plants and their maintenance, during which often no CCP can be operated. This applies to the exposure areas in the underwater and sediment area. This problem is intensified by the difficult to estimate corrosion rates caused by the different zones, with their different amounts of dissolved oxygen and the various influencing factors. This paper deals with experiments conducted in a laboratory container with artificial seawater and sediment in basins. T2 - AMPP Annual Conference + Expo 2025 CY - Nashville, TN, USA DA - 06.04.2025 KW - Seawater KW - Sediment KW - Corrosion KW - Offshore KW - Foundation KW - Element current PY - 2025 DO - https://doi.org/10.5006/C2025-00002 SP - 1 EP - 16 PB - AMPP CY - Houston TX USA AN - OPUS4-62963 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bäßler, Ralph T1 - Investigation of corrosion behavior of S355 steel in artificial seawater and sediment N2 - The safe operation of offshore wind turbines places high demands on corrosion protection. This is particularly the case about the planned future extension of the service life beyond 25 years. The highly corrosive environment towards metallic materials leads to a loss of material thickness of the tower structure and thus to a deterioration of mechanical properties. This can be counteracted by corrosion protection measures adapted to the respective load case, such as organic coatings and cathodic corrosion protection (CCP). Much research has already been done in this area about inhibiting the corrosion process and there are regulations and guidelines that specify requirements for corrosion protection to achieve the required service lives. However, gaps exist regarding free corrosion. This plays a greater role especially for time intervals during the installation of the plants and their maintenance, during which often no CCP can be operated. This applies to the exposure areas in the underwater and sediment area. This problem is intensified by the difficult to estimate corrosion rates caused by the different zones, with their different amounts of dissolved oxygen and the various influencing factors. This paper deals with experiments conducted in a laboratory container with artificial seawater and sediment in basins. T2 - AMPP Annual Conference + Expo 2025 CY - Nashville, TN, USA DA - 07.04.2025 KW - Seawater KW - Sediment KW - Corrosion KW - Offshore KW - Foundation KW - Element current PY - 2025 AN - OPUS4-62964 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Seifert, Lando A1 - Fabian, Maxine A1 - Ebell, Gino T1 - Spannungsrisskorrosion von Spannstählen N2 - Im Rahmen des Events des Berufsnetzwerks "die junge gfkorr" der Gesellschaft für Korrosionsschutz e.V. wurde dieser Fachvortrag Spannungsrisskorrosion von Spannstählen gehalten. Als Einstieg wurde der prominente Schadensfall des Teileinsturz der Carolabrücke in Dresden gezeigt. Aktuelle Forschungen des Fachbereich 7.6 auf dem Gebiet fokussieren sich auch auf dem Einfluss von atmosphärischen Schwefeldioxids auf die Rissinitiierung, der Weiterentwicklung von Spannungsrisskorrosionstest für Spannstähle und der Mitarbeit neuer Tools zur Abschätzung von Restnutzungsdauern gefährdeter Bestandsbrücken. T2 - die junge gfkorr @ Dörken Coatings CY - Herdecke, Germany DA - 26.05.2025 KW - Spannstahl KW - Spannungsrisskorrosion KW - Carolabrücke KW - Schwefeldioxid PY - 2025 AN - OPUS4-63264 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Steinbock, O. A1 - Bösche, T. A1 - Ebell, Gino A1 - Kaplan, F. A1 - Marzahn, G. T1 - Erfahrungen aus dem Rückbau der Brücke am Altstädter Bahnhof in der Stadt Brandenburg N2 - Bei der Brücke Altstädter Bahnhof handelte es sich um eine große Spannbetonkonstruktion, die einen elementaren Ver­kehrsknotenpunkt in der Stadt Brandenburg an der Havel bil­dete. Entgegen üblichen Spannbetonkonstruktionen mit kleinen Bündelspanngliedern kamen beim Haupttragwerk in Längsrich­tung großformatige Spannblockspannglieder zum Einsatz. Im Fall der vorliegenden Brücke setzte sich das Spannglied aus 392 ovalen Einzeldrähten aus Hennigsdorfer Produktion zusam­men, welche als spannungsrisskorrosionsgefährdet gelten. Bei Bauwerkserkundungen wurde ein hoher Versprödungsgrad der Spannstähle festgestellt, sodass die Brücke am 19.05.2021 ge­sprengt werden musste. Zuvor traten im Bereich detektierter Spanndrahtbrüche von außen erkennbare Längsrisse in den Stegen anstatt von üblicherweise quer gerichteten Biegerissen an der gezogenen Randfaser auf. Die abweichende Schadens­äußerung im Falle einer Spannstahlschädigung brachte das Bundesministerium für Digitales und Verkehr (BMDV) dazu, weitergehende Untersuchungen durchzuführen. In Zusammen­arbeit mit dem Landesbetrieb Straßenwesen Brandenburg, der Hochschule für Technik und Wirtschaft Dresden sowie der Bundesanstalt für Materialforschung und ­prüfung (BAM) wur­den experimentelle Untersuchungen in­situ konzipiert und durchgeführt. Im Konkreten wurde an zwei Messstellen eine gezielte Schädigung des großformatigen Spannglieds vorge­nommen, um das zuvor vorgefundene Schadensbild nach­zuvoll ziehen und validieren zu können. Konzept, Ergebnisse aus den Untersuchungen und Erkenntnisse für gleichartig ausge­führte Bauwerke sind Gegenstand des ersten Beitrags (Teil 1). Der zweite Teil [1] wird sich im Schwerpunkt den verwendeten Messverfahren und Monitoringsystemen widmen, welche die Durchführung des Versuchs begleiteten. KW - Korrosion KW - Spannungsrisskorrosion KW - Spannstahl KW - Wasserstoff PY - 2022 DO - https://doi.org/10.1002/best.202200051 VL - 117 IS - 1 SP - 572 EP - 580 PB - Ernst & Sohn CY - Berlin AN - OPUS4-55329 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ebell, Gino T1 - Spannbetonbauwerke - Von der Initiierung zum Schaden N2 - Wasserstoffinduzierte Spannungsrisskorrosion an hochfesten und hochempfindlichen Spannstählen führt an bestehenden Brückenbauwerken nach Jahren der Rissinitiierung zu Trag- und Standsicherheitsverlusten. Anhand des Beispiels der Brücke am Altstädter Bahnhof gibt es eine bauartbedingte Schadensinitiierung die über den gesamten Spannkanalquerschnitt zu Spannungsrisskorrosion führen kann. T2 - 3-Länder Korrosionstagung CY - Zurich, Switzerland DA - 28.10.2021 KW - Korrosion KW - Spannstahl KW - Spannungsrisskorrosion PY - 2021 AN - OPUS4-53676 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Benseghier, Z. A1 - Cuéllar, Pablo A1 - Luu, L.-H. A1 - Bonelli, S. A1 - Philippe, P. T1 - A parallel GPU-based computational framework for the micromechanical analysis of geotechnical and erosion problems N2 - This article deals with the relevance and practical feasibility of micromechanical simulations for their application to general geomechanical problems involving fluid-saturated granular assemblies, whether frictional or cohesive. A set of conceptual and numerical tools is here presented, advocating for a parallel computation using graphical processing units (GPUs) to treat large numbers of degrees of freedom with conventional Desktop computers. The fluid phase is here simulated with a particle-resolved approach in the frame of the Lattice Botzmann Method (LBM) while the granular solid phase is modelled as a collection of discrete particles from a Molecular Dynamics DEM perspective. The range of possible material behaviours for the solid granular phase is intended here to cover a broad spectrum from purely frictional to viscous cohesive materials with either brittle or transient debonding features. Specific details of the implementation and some validation cases are put forward. Finally, some exemplary applications in the fields of soil erosion and geotechnical profile installation are provided along with a discussion on the parallel performance of the presented models. The results show that a micromechanical approach can be feasible and useful in practice, providing meaningful insights into complex engineering problems like the erosion kinetics of a soil under an impinging jet or the penetration resistance of a deep foundation in a layered soil profile. KW - Offshore geomechanics KW - Erosion KW - Micromechanical modelling KW - LBM-DEM KW - GPU Parallel computing PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-502309 DO - https://doi.org/10.1016/j.compgeo.2019.103404 VL - 120 SP - Paper 103404, 1 PB - Elsevier Ltd. AN - OPUS4-50230 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Balscheit, Hagen A1 - Geißler, Peter A1 - Cuéllar, Pablo A1 - Basedau, Frank A1 - Baeßler, Matthias T1 - Large-scale field tests on plastic pile tip failure upon monopile installation N2 - Large-diameter monopiles are the most common foundation structures for offshore wind turbines. One relevant failure mode during installation is plastic failure of the pile tip which may increase progressively during further driving (pile tip buckling; extrusion buckling). This paper presents the details and results of a large-scale field-test campaign with dynamic pile installation for the validation and calibration of different numerical approaches concerning pile-tip buckling phenomena. The phenomenology of observed pile-tip failures is here described in detail and a first quantitative approach is evaluated based on the field-test data. As the number of new projects continues to grow and the necessity to construct wind farms in challenging terrain increases, such field data-sets will become increasingly relevant. KW - Monopile KW - Offshore Windenergy KW - Pfahlfußbeulen KW - Pile Tip Buckling KW - Reference Tests PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-611651 DO - https://doi.org/10.1016/j.oceaneng.2024.119322 VL - 313 SP - 1 EP - 14 PB - Elsevier B.V. AN - OPUS4-61165 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Balscheit, Hagen A1 - Victor, A. A1 - Thiele, Marc A1 - Cuéllar, Pablo A1 - Baeßler, Matthias A1 - Lüddecke, F. T1 - Experimental Investigation on Buckling Behavior of soil-embedded Piles N2 - Monopiles are currently the predominant foundation type for offshore wind turbines in Europe. Due to the increasing dimensions of the turbines, pile diameters beyond 10m become necessary. A design-relevant failure mode of monopiles is the local buckling of the pile wall in the embedded sections. Relevant buckling guidelines do not consider the soil-structure interaction specifically, although the embedment may allow for a reduction of wall thickness. However, Eurocode-based design concepts require a validation with comparative buckling cases for validation, either in terms of buckling curve parameters for both the algebraic stress-based and semi-numerical LBA/MNA design concept or as a calibration factor kGMNIA for fully numerical GMNIA calculations. These parameters are not yet available for embedded shells. To close this gap, we have conducted experiments on piles embedded in sand to investigate local buckling under soil-structure-interaction. The results will be used to calibrate numerical models. This research was carried out as part of the VERBATIM research project, funded by PTJ/BMWK and supported by the Carbon Trust's Offshore Wind Accelerator consortium. T2 - EUROSTEEL 2023 CY - Amsterdam, The Netherlands DA - 11.09.2023 KW - Wind KW - Wind Energy KW - Shell Buckling KW - Offshore KW - Soil-Structure-Interaction PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-583641 DO - https://doi.org/10.1002/cepa.2313 SN - 2509-7075 VL - 6 IS - 3-4 SP - 1729 EP - 1734 PB - Ernst & Sohn Gmb AN - OPUS4-58364 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Zinas, Orestis A1 - Papaioannou, Iason A1 - Schneider, Ronald A1 - Cuéllar, Pablo A1 - Baeßler, Matthias T1 - 3D spatial modelling of CPT data for probabilistic preliminary assessment of potential pile tip damage upon collision with boulders N2 - Tip damage of monopiles from boulder collisions during installation has emerged as a critical design issue, primarily due to the combination of the widespread use of large-diameter piles and the complexity of the ground conditions at the available sites. Recently, a framework relating potential pile tip damage to cone tip resistance from Cone Penetration Tests (CPTs) has been proposed in the literature. Gaussian processes are powerful stochastic models that enable probabilistic spatial interpolation of soil data at any location within a site. On this basis, this study utilizes sparse CPT data from a site in the North Sea, to first develop an efficient Gaussian process regression model, which is used to derive a three-dimensional (3D) probabilistic predictive map of the cone tip resistance. Assuming deterministic loading conditions and a factual collision with a boulder of pre-defined properties, the cone tip resistance predictive model is subsequently used for a probabilistic preliminary assessment of potential pile tip damage. Results of the analysis are realistic 3D probability maps of potential damage that aim to support engineering judgment and contribute towards cost-effective site investigation planning and offshore wind farm design. T2 - 5th International Symposium on Frontiers in Offshore Geotechnics (ISFOG 2025) CY - Nantes, France DA - 09.06.2025 KW - CPT data KW - Gaussian process regression KW - Boulder impact KW - Preliminary pile tip damage assessment PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-634417 SN - 978-2-85782-758-0 DO - https://doi.org/10.53243/ISFOG2025-323 SP - 505 EP - 510 PB - International Society for Soil Mechanics and Geotechnical Engineering CY - London AN - OPUS4-63441 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Baeßler, Matthias A1 - Balscheit, Hagen A1 - Geißler, Peter A1 - Schepers, Winfried A1 - Cuèllar, Pablo T1 - Evaluation of pile tip buckling based on large scale tests N2 - Der Beitrag beschreibt eine groß angelegte Versuchskampagne mit Pfahlrammungen, um das Risiko des plastischen Versagens der Pfahlspitze besser zu verstehen und numerische Modelle zu validieren. Ein numerisches Modell mit transientem Bodenkontakt zeigt eine gute Übereinstimmung mit den Testergebnissen. Parametervariationen verdeutlichen, wie empfindlich die Pfahlreaktion auf Imperfektionen und Randbedingungen ist. T2 - 5TH INTERNATIONAL SYMPOSIUM ON FRONTIERS IN OFFSHORE GEOTECHNICS CY - Nantes, France DA - 09.06.2025 KW - Pile Tip Buckling KW - Monopile KW - Offshore Windenergy KW - Driving Refusal KW - Large Scale Test PY - 2025 SN - 978-2-85782-758-0 DO - https://doi.org/10.53243/ISFOG2025-476 SP - 1218 EP - 1223 PB - International Society for Soil Mechanics and Geotechnical Engineering (ISSMGE) CY - Nantes AN - OPUS4-63387 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kullolli, Borana A1 - Cuéllar, Pablo A1 - Baeßler, Matthias A1 - Stutz, H. H. T1 - Modelling and calibration for cyclic soil-structure interface behaviour N2 - The structural performance of many geotechnical systems (e.g. axially-loaded pile foundations), depends on the shearing resistance at the soil interface, which may govern the load bearing capacity of the foundation. Experimental investigations have shown that this interaction is mainly localised within a narrow shear band next to the structure. Under cyclic loading, a contraction of the soil at the interface may arise (net volume loss), possibly leading to a stress relaxation and thus to a reduction of the load bearing capacity (the so-called friction fatigue). Based on the constitutive similarities between soil continua and interfaces, we propose here the adaption of a Generalized Plasticity model for sandy soils for the numerical analysis of interface problems. In this contribution, the results of an experimental campaign for the parameter calibration of the constitutive model are presented. The tests have been conducted with a ring shear device involving different normal stresses, roughness of the steel plates as well as cyclic loading. The new modelling approach shows promising results and has the additional practical advantage that the interface zone and the soil continuum can both be described with the same constitutive model in general boundary value problems. T2 - Konferenz 7th International Symposium on Deformation Characteristics of Geomaterials CY - Glasgow, Scotland DA - 26.06.2019 KW - Soil-structure interaction KW - Offshore foundations PY - 2019 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-489096 DO - https://doi.org/10.1051/e3sconf/20199213007 VL - 92 SP - 13007 EP - 13013 PB - EDP Sciences CY - Glasgow, Scotland AN - OPUS4-48909 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Zinas, Orestis T1 - 3D spatial modelling of CPT data for probabilistic preliminary assessment of potential pile tip damage upon collision with boulders N2 - Tip damage of monopiles from boulder collisions during installation has emerged as a critical design issue, primarily due to the combination of the widespread use of large-diameter piles and the complexity of the ground conditions at the available sites. Recently, a framework relating potential pile tip damage to cone tip resistance from Cone Penetration Tests (CPTs) has been proposed in the literature. Gaussian processes are powerful stochastic models that enable probabilistic spatial interpolation of soil data at any location within a site. On this basis, this study utilizes sparse CPT data from a site in the North Sea, to first develop an efficient Gaussian process regression model, which is used to derive a three-dimensional (3D) probabilistic predictive map of the cone tip resistance. Assuming deterministic loading conditions and a factual collision with a boulder of pre-defined properties, the cone tip resistance predictive model is subsequently used for a probabilistic preliminary assessment of potential pile tip damage. Results of the analysis are realistic 3D probability maps of potential damage that aim to support engineering judgment and contribute towards cost-effective site investigation planning and offshore wind farm design. T2 - 5th International Symposium on Frontiers in Offshore Geotechnics (ISFOG) CY - Nantes, France DA - 09.06.2025 KW - CPT data KW - Gaussian process regression KW - Boulder impact KW - Preliminary pile tip damage assessment PY - 2025 AN - OPUS4-63444 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Maack, Stefan T1 - Testing to reasses - Corrosion activity assessment based on NDT using a prestressed concrete bridge as case study N2 - Corrosion of concrete reinforcement is one of the major damage mechanisms affecting both the load-bearing capacity and the serviceability of reinforced concrete structures significantly. The challenge of detecting corrosion is that the corrosion process in its various forms is not immediately visible, especially in the corrosion initiation phase inside the concrete. When externally discernible damages are observed during visual inspections on the structure, the extent of the damage inside the concrete is often already significant. Corrosion caused by carbonation often leads to severe discoloration of the surface or even large-area spalling of the concrete cover. In contrast, chloride-induced corrosion is usually difficult to observe visually, but can cause much more serious damage in less time. The effect occurs locally and can lead to weakening of the cross-section of the reinforcement. This, in turn, can cause sudden structural collapses without prior notice. Therefore, it is important to investigate whether there is protection against corrosion of the reinforcement in the concrete and to detect active corrosion in the structure at an early stage. In the meanwhile, various non-destructive and minimally invasive testing methods are available to evaluate the resistance to penetration of corrosion-promoting pollutants and to detect active corrosion. In this paper, a bridge crossing the river Regen (Germany) is used as a case-study to demonstrate how the information obtained applying different testing methods can be combined and evaluated in the context of structural reassessments. Both the results of the permeability testing (Torrent tester) and the electrical resistance measurement (Wenner probe) are considered, as well as active corrosion areas are localized using the half-cell potential mapping combined with the concrete cover measurement with the eddy current method and ground penetrating radar (GPR). The results are evaluated using drill cores and in addition laser-induced breakdown spectroscopy (LIBS) was applied to obtain information about possible ion transport in the concrete. T2 - EUROSTRUCT 2021 - 1st Conference of the European Association on Quality Control of Bridges and Structures - EUROSTRUCT CY - Padova, Italy DA - 30.08.2021 KW - Nondestructive testing KW - Corrosion KW - Bridge KW - Durability assessment KW - Civil engineering PY - 2021 AN - OPUS4-53222 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Seifert, Lando T1 - Review: Steel‐Reinforced Concrete Str‐uctures: Assessment and Repair of Corrosion N2 - In 2019 CRC Press published the "Steel‐Reinforced Concrete Structures" as a paperback. This book does not vary in terms of content from the hardback publication of 2008. But it is first reviewed here in corrosion news. The book provides eight of nine chapters in which the author discusses technical aspects of assessment and repair of steel‐reinforced concrete structures. To sum up, this book is recommended for students and people involved with the assessment and repair of reinforced‐concrete structures, who want to get a quick introduction into the different aspects of the field. Readers also learn much about the economic interactions besides the topic. However, for experienced technicians and corrosion experts, this book may not be exact enough in both the electrochemical description of deterioration processes and the practical aspects of repair and control methods. Despite that, the discussions of the author are scientifically correct. KW - Concrete KW - Corrosion PY - 2020 DO - https://doi.org/10.1002/maco.202070084 SN - 1521-4176 SN - 0947-5117 VL - 71 IS - 8 SP - 1408 EP - 1409 PB - WILEY‐VCH Verlag GmbH & Co. KGaA CY - Weinheim AN - OPUS4-51075 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kemmler, Samuel T1 - Gekoppelte Fluid Partikel Simulationen einer Suction Bucket Gründung zur Analyse von Piping Erosion während der Installation von Offshore Windkraftanlagen N2 - Wir stellen unseren Ansatz und unsere Methodik zur Simulation von Piping-Erosion vor, welche während des Installationsprozesses von Suction Bucket Fundamenten für Offshore-Windkraftanlagen auftreten kann und ein kritisches Versagen des Installationsprozesses darstellt. Wir zeigen die Ergebnisse mehrere Simulationen und analysieren die hydrodynamischen und Kontaktkräfte, die auf das granulare Medium wirken, sowie die Druckdifferenz der flüssigen Phase. Solche Simulationen können zum besseren Verständnis von Piping-Erosion und letztendlich zu dessen Verhinderung beitragen. T2 - Gesinus-Treffen 2024 CY - Stuttgart, Germany DA - 20.06.2024 KW - Suction Bucket KW - Gekoppelte Fluid-Partikel Simulationen KW - Offshore-Windkraftanlagen PY - 2024 AN - OPUS4-60516 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Gluth, Gregor T1 - Chloride binding by LDH/AFm phases and alkali-activated slag pastes N2 - Chloride binding by the hydrate phases of cementitious materials influences the rate of chloride ingress into these materials and, thus, the time at which chloride reaches the steel reinforcement in concrete structures. A particularly important role in this context is played by layered double hydroxides (LDHs), including AFm phases. Chloride binding isotherms of individual LDH/AFm phases would be required as input for computational models of chloride ingress, but such isotherms are only available for a few AFm phases, and in addition the available data are partly conflicting. The present study, conducted in the context of RILEM TC 283-CAM ‘Chloride transport in alkali-activated materials’, significantly extends the available database by determining the chloride binding isotherms of LDH/AFm phases (monosulfate, strätlingite, hydrotalcite, and meixnerite), and of alkali-activated slags (AAS) produced with four different activators (Na2SiO3, Na2O∙1.87SiO2, Na2CO3, and Na2SO4), in NaOH/NaCl solutions at various liquid/solid ratios. Selected solids after chloride binding were analysed by X-ray diffraction, and thermodynamic modelling was applied to simulate the phase changes occurring during chloride binding by the AFm phases. The chloride binding isotherms of LDH/AFm phases depended strongly on the liquid/solid ratio during the experiments, resolving apparent contradictions of the previously available data. The dependency on liquid/solid ratio must be attributed to kinetic restrictions, which are, however, currently poorly understood. Chloride binding by AAS pastes was generally higher than for Portland cement pastes and was only moderately influenced by the employed activator. A steep increase of the chloride binding by AAS occurred at free chloride concentrations above approx. 1.0 M, which is possibly related to chloride binding by the C-(N-)A-S-H gel in the AAS. T2 - RILEM Spring Convention 2024 & Conference on Advanced Construction Materials and Processes for a Carbon Neutral Society CY - Milan, Italy DA - 07.04.2024 KW - Chloride binding KW - Layered double hydroxides KW - AFm phases KW - Alkali-activated slags KW - Chloride sorption isotherms PY - 2024 AN - OPUS4-59855 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ebell, Gino T1 - Potentialfeldmessung in Theorie und Praxis N2 - Durch das alkalische Porenwassermilieu ist Stahl im Beton vor Korrosion geschützt. Unter ungünstigen Umgebungsbedingungen (Karbonatisierung, Chlorideintrag) kann die passive Deckschicht auf der Stahloberfläche zerstört werden. Im weiteren Verlauf können sich korrosionsbedingte Folgeschäden, wie Risse und Abplatzungen am Bauwerk ergeben. Um notwendige Sanierungsmaßnahmen sind frühzeitige und weitgehend zerstörungsfrei ermittelte Informationen über das aktuelle Korrosionsverhalten der Stahlbewehrung von großer Bedeutung. Die Potentialfeldmessung ist ein etabliertes und weit verbreitetes Verfahren zur Beurteilung des Korrosionszustandes der Bewehrung in Stahlbetonbauwerken. Mit Hilfe dieses Verfahrens können Bereiche aktiv korrodierender Bewehrung zerstörungsfrei lokalisiert werden. In der Regel kommt diese Messmethode bei der Detektion chloridinduzierter Korrosion zum Einsatz T2 - TU-Berlin Vorleseung CY - Berlin, Germany DA - 05.06.2024 KW - Korrosion KW - Potentielfeldmessung PY - 2024 AN - OPUS4-60975 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ebell, Gino T1 - Befestigungsmittels im Bauwesen - Der richtige Werkstoff??? N2 - Die Anforderungen in verschiedenen Fachgebieten des Bauwesens an metallene Befestigungsmittels hinsichtlich des Korrosionsschutzes sind zum einen Abhängig von den verwendeten Werkstoffen und zum anderen von der Korrosivität in der jeweiligen Exposition. Hier wird ein Überblick über die gängigen Werkstoffe als auch Anwendung und Fehlerquellen verschaff T2 - TU-Berlin Vorleseung CY - Berlin, Germany DA - 05.06.2024 KW - Korrosion KW - Corrosion PY - 2024 AN - OPUS4-60974 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ebell, Gino T1 - Zur Deckschichtbildung an feuerverzinkten Betonstählen in chloridhaltigen Mörteln N2 - Die Deckschichtbildung an feuerverzinkten Betonstählen in chloridhaltigen Mörteln oder Betonen unterscheidet sich hinsichtlich der Korrosionseigenschaften signifikant von chloridfreien Systemen. Diese Unterschiede wurden in der dargestellten Arbeit dezidiert untersucht und dargestellt, als auch die Wechselwirkung mit dem Mörtel bei direkter Chloridzugabe. T2 - Sitzung des AK Kiki CY - Hamburg, Germany DA - 14.05.2024 KW - Korrosion KW - Verzinkt PY - 2024 AN - OPUS4-60979 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ebell, Gino T1 - Atmospheric Corrosion and Run Off of Zinc and Copper - A Field and Laboratory Study N2 - Often corrosion rates are determined to get an idea of the corrosivity of the atmosphere. The calculated mass loss does not reflect the ingress of metal ions into the environment. Therefore, the runoff project was started to determine the metal ion ingress with respect to rain events for zinc and copper. T2 - Eurocorr 2024 CY - Paris, France DA - 01.09.2024 KW - Corrosion KW - Run-Off KW - Ions KW - Korrosion KW - Zinc KW - Zink PY - 2024 AN - OPUS4-60971 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Haacke, Nasrin T1 - Forschungsvorhaben RUNOFF - Aktueller Projektstand N2 - Dieser Vortrag gibt einen Überblick zum aktuellen Forschungsstand des Projekts RUNOFF mit dem Fokus auf Kupfer. T2 - GfKorr AK Korrosion und Korrosionsschutz von Kupfer und Kupferlegierungen CY - Online meeting DA - 14.12.2023 KW - Schwermetalle KW - Runoff KW - Kupfer KW - Deckschichtwiderstand KW - Zink KW - Dauerhaftigkeit PY - 2023 AN - OPUS4-59152 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ebell, Gino A1 - Gündel, M. T1 - Anwendung der Feuerverzinkung zum Korrosionsschutz im Stahlwasserbau N2 - Feuerverzinkungen sind im Stahlwasserbau als primäre Korrosionsschutzmaßnahme nicht etabliert. Neu Legierungszusammensetzungen der Schmelztauchüberzüge bieten jedoch ausreichend Potential um die Dauerhaftigkeit von Stahlwasserbauten im üblichen Maße sicherstellen zu können. T2 - Forschungsbeiratssitzung des GAV CY - Darmstadt, Germany DA - 06.06.2024 KW - Korrosion KW - Potentialfeldmessung KW - Zink KW - Stahlwasserbau PY - 2024 AN - OPUS4-60587 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ebell, Gino A1 - Achenbach, R. A1 - Harnisch, J. T1 - The dgzfp Subcommittee „Corrosion Detection in Reinforced Concrete“ N2 - The subcommittee “Corrosion Detection in Reinforced Concrete” is a technical committee within the scope of the German Society for Non-Destructive Testing (DGZfP). The international working group consists of engineers and scientists from Germany, Austria and Switzerland who work at research institutes or engineering firms and aims for the practical implementation of non-destructive testing in civil engineering (NDT-CE) methods to assess the corrosion condition of reinforced concrete (RC) structures. Therefore, the group works on technical specifications that explain the necessary theoretical background of the presented techniques but mainly provide helpful instructions for the application on-site and in the laboratory. Based on the corrosion process of steel in concrete the specifications focus on selected topics where the field engineer is getting into contact with the phenomenon. Therefore, specification B 12 highlights corrosion monitoring in reinforced and prestressed concrete structures and presents different approaches to monitor the initiation and propagation phase of corrosion and shows case studies of where these techniques were applied successfully. Specification B 03 deals with the potential-mapping technique. In addition to this specification, practical training courses and certification in this method have been developed and are offered by the working group members and are organized by the DGZfP. Both specifications, B 03 as well as B 12, are available in English. In the case of specification B 03, the current version is still in the translation process and will be available soon. Currently, the group is working on a new specification for measuring the electrical resistivity of cementitious materials, for example, to evaluate the suitability of mortars for cathodic protection applications and to validate the influence of the concrete resistivity with regard to corrosion processes of steel in concrete. Given the increasing impact of corrosion damages on infrastructural structures, the working group would like to introduce the use of the mentioned specifications to an interested international audience and thus offer the possibility to reliably detect corrosion damages at an early stage to prevent significant damages or high repair costs on RC structures. T2 - ICCRRR 2024 CY - Cape Town, South Africa DA - 03.11.2024 KW - Corrosion KW - Monitoring PY - 2024 AN - OPUS4-61603 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Carabba, L. A1 - Pirskawetz, Stephan A1 - Krüger, Simone A1 - Gluth, Gregor A1 - Bignozzi, M.C. T1 - Acoustic emission study of heat-induced cracking in fly ash-based alkali-activated pastes and lightweight mortars N2 - Alkali-activated fly ashes have been proposed for various applications where resistance against high temperatures is required, yet several details regarding the response of these materials to heat-exposure need to be clarified. In the present study, heat-induced cracking in fly ash-based alkali-activated pastes and lightweight mortars was analyzed by in-situ acoustic emission (AE) detection during complete heating-cooling cycles (up to ∼1100 °C), augmented by thermogravimetry and ex-situ SEM and XRD analyses. The applicability of the lightweight mortars as passive fire protection coatings was assessed by recording temperature-time curves of mortar-coated steel plates. Cracking during heating was limited and associated exclusively with the dehydration of the materials in the temperature range ∼90–360 °C. However, samples heated to temperatures above ∼600 °C exhibited intense cracking on cooling. This was attributed to differential deformations caused by local sintering and partial melting at the glass transition temperature, and subsequent quenching on cooling. KW - Alkali-activated materials KW - Acoustic emission KW - Fire proofing KW - Heat resistance KW - Cracking PY - 2019 DO - https://doi.org/10.1016/j.cemconcomp.2019.04.013 SN - 0958-9465 SN - 1873-393X VL - 102 SP - 145 EP - 156 PB - Elsevier AN - OPUS4-47904 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Mundra, Shishir A1 - Samson, G. A1 - Masi, G. A1 - Achenbach, R. A1 - Bastidas, D. M. A1 - Bernal, S. A. A1 - Bignozzi, M. C. A1 - Criado, M. A1 - Cyr, M. A1 - Gartner, N. A1 - von Greve-Dierfeld, S. A1 - Legat, A. A1 - Nikoonasab, Ali A1 - Provis, J. L. A1 - Raupach, M. A1 - Gluth, Gregor T1 - Stahlkorrosion in alkalisch aktivierten Bindemitteln und Betonen: Anwendung elektrochemischer Methoden N2 - Alkalisch aktivierte Bindemittel (AAB) und Betone können herkömmliche Zemente beziehungsweise Betone potentiell in vielen Anwendungen ersetzen und dadurch den CO2-Fußabdruck der Bauindustrie wesentlich verkleinern. Zur Untersuchung der Stahlkorrosion in bewehrten („armierten“) Betonbauteilen werden elektrochemische Methoden wie Messungen des Freien Korrosionspotentials, des Polarisationswiderstands oder von Stromdichte-Potential-Kurven eingesetzt. Diese Methoden und die etablierten Grenzwerte zur Detektion von Korrosion sind für die Anwendung bei herkömmlichen Zementen beziehungsweise Betonen entwickelt und erprobt worden. Neue Forschungsergebnisse demonstrieren, dass Unterschiede zwischen den Porenlösungszusammensetzungen von herkömmlichen Zementen und bestimmten AAB sowie anderen schlackehaltigen Zementen erhebliche Unterschiede bei den Ergebnissen der elektrochemischen Messungen bewirken und damit zur fehlerhaften Detektion von Stahlkorrosion führen können. Ursache hierfür sind vor allem reduzierte Schwefelspezies in den Porenlösungen von AAB und anderen schlackehaltigen Zementen. KW - Zement KW - Hüttensandmehl KW - Schlacke KW - Sulfid KW - Korrosion PY - 2023 UR - https://bit.ly/GIT-Gluth UR - https://analyticalscience.wiley.com/content/magazine-do/git-labor-fachzeitschrift-10-2023 SN - 0016-3538 VL - 67 IS - 10 SP - 28 EP - 31 PB - Wiley-VCH AN - OPUS4-58573 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ebell, Gino T1 - Risiko der Wasserstoffentwicklung an martensitischen Schraubankern unter baupraktischen Bedingungen N2 - Die vorliegende Untersuchung beschäftigt sich mit der Fragestellung ob unter praxisrelevanten Bedingungen die Entstehung von Wasserstoff an vollmartensitischen Schraubankern möglich ist. Im Gegensatz zu austenitischen Werkstoffen besteht bei martensitischen Werkstoffen bei Gegenwart von Wasserstoff stets die Möglichkeit einer wasser-stoffinduzierten Versprödung des Materials. Hierfür wurde ein in der Praxis häufig anzutreffendes Szenario gewählt, das ein galvanisches Element, bestehend aus nichtrostenden Schraubankern (in diesem Fall martensitischen) und einer verzinkten Ankerplatte an einem Betonkörper, umfasst. Zum Nachweis einer Wasserstoffentwicklung wird der Elementstrom zwischen den Bauteilen sowie das Korrosionspotential erfasst. Die Ergebnisse der Versuche zeigen, dass über eine zeitlich begrenzte Dauer eine starke kathodische Polarisation der martensitischen Schraubanker durch die korrosive Auflösung des Zinks erfolgt. Als Folge kommt es zur Wasserzersetzung im Phasengrenzbereich der Schraubanker und zur Entstehung von atomarem Wasserstoff. Das berechnete Gasvolumen des entstandenen Wasserstoffs an den Stahlankern wurde bestimmt und lag im Mittel bei 11,14 ± 1,94 ml. Eine Diffusion des an der Stahloberfläche adsorbierten Wasserstoffs in den martensitischen Werkstoff ist somit theoretisch möglich und impliziert eine mögliche Gefährdung durch wasserstoffinduzierte Rissbildung und spontanem Versagen unter Belastung. T2 - Arbeitskreis Korrosionsschutz im konstruktiven Ingenieurbau CY - Online meeting DA - 24.09.2020 KW - Korrosion KW - Wasserstoff PY - 2020 AN - OPUS4-51309 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CHAP A1 - Baeßler, Matthias A1 - Cuéllar, Pablo A1 - Victor, A. A1 - Lüddecke, F. ED - Triantafyllidis, T. T1 - Stability and large deformations of slender structures supported by soil materials N2 - The stability and geometric nonlinearities of slender structures are a major topic in structural design. While this topic is most relevant in the field of Structural Engineering, e.g. for steel or concrete structures, only few applications take the role of soil-structure-interaction explicitly into account. The focus of this paper is placed on the impact of soil support and its modelling for the buckling analysis based on examples both for pile foundations and for railway track stability. The general interaction between steel design and the geotechnical input will be addressed. The paper discusses and summarizes a range of subtopics based on experience and current research at the author’s institute. KW - Buckling soil-structure-interaction offshore piles track PY - 2020 SN - 978-3-030-28515-9 SN - 978-3-030-28516-6 DO - https://doi.org/10.1007/978-3-030-28516-6 SN - 1613-7736 SN - 1860-0816 VL - 91 SP - 355 EP - 369 PB - Springer CY - Cham, Switzerland AN - OPUS4-49166 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Baeßler, Matthias T1 - Numerical Modelling of Local Pile Deformations and Buckling incorporating the Pile-Soil-Interaction N2 - Pile Tip Buckling and Buckling of embedded piles both depend very much on the pile-soil-interaction and its modelling. The presentation gives an overview about current problems and research activities in the light of the development of numerical models. T2 - WESC Wind Energy Science Conference CY - Hannover, Germany DA - 25.05.2021 KW - Offshore Wind Energy Converter KW - Pile Foundation KW - Monopile Buckling KW - Pile Tip Buckling PY - 2021 AN - OPUS4-53033 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Grengg, C. A1 - Koraimann, G. A1 - Ukrainczyk, N. A1 - Rudic, O. A1 - Luschnig, S. A1 - Gluth, Gregor A1 - Radtke, Martin A1 - Dietzel, M. A1 - Mittermayr, F. T1 - Cu- and Zn-doped alkali activated mortar – Properties and durability in (bio)chemically aggressive wastewater environments N2 - Metakaolin-based alkali activated mortars (AAM) - with and without CuSO4·5H2O and ZnO addition (mass ratio Mn+/solid binder 0.08% to 1.7%) - were casted and exposed within an extensive long-term field campaign over the period of 20 months to a sewer basin, strongly affected by biogenic acid corrosion. (Un-)exposed AAM were tested regarding their physicochemical and microstructural properties, bioreceptivity and overall durability. Metal addition led to a retarding effect during alkali-activation reaction, as well as to an increase in open porosity of up to 3.0% and corresponding lower compressive strength of up to 10.9%. Reduced microbial colonization and diversity were observed on AAM with Cu, while Zn addition led to increased biodiversity. We propose that the observed higher durability of Cu-doped AAM is due to antibacterial effects and associated reduction of biogenic acid production, superseding overall negative effects of metal-dosage on physical material properties. Observed lower durability of Zn-doped AAM was related to combined negative physicochemical and microbial effects. KW - Microbially induced corrosion KW - Alkali-activated materials KW - Biogenic acid corrosion KW - Biogene Schwefelsäurekorrosion KW - MIC PY - 2021 DO - https://doi.org/10.1016/j.cemconres.2021.106541 SN - 0008-8846 VL - 149 SP - 1 EP - 15 PB - Elsevier CY - Oxford AN - OPUS4-53070 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Gluth, Gregor A1 - Garel, S. ED - Valente, I. B. ED - Ventura Gouveia, A. ED - Dias, S. S. T1 - Calorimetry Study of the Influence of Portland Cement Content, Slag/Fly Ash Ratio, and Activator Type on the Early Hydration of Hybrid Cements N2 - Hybrid cements (cements composed of Portland clinker, supplementary cementitious materials and an alkaline activator) potentially combine advantages of conventional cements with those of alternative binders, such as low heat of hydration and improved durability in some environments. While fly ash-based hybrid cements have been studied in considerable detail, slag-dominated hybrid cements appear to have received less attention. Here, the latter materials have been studied by isothermal calorimetry, X-ray diffraction and strength testing. The heat of hydration of these cements was as low as ~50% of that of an ordinary Portland cement, while their strength after 28-day curing was in the range 31–61 MPa. The phase assemblages after 28-day curing depended on the activator, with Na2SO4 leading to ettringite and Na2CO3 leading to hemicarbonate formation, respectively, besides C–A–S–H, portlandite and hydrotalcite. The U phase was identified when a high Na2SO4 dose and/or fly ash was employed. Na2SO4 accelerated the early reaction of the Portland clinker, while Na2CO3 appeared to decrease the extent of reaction of the clinker and led to a shift of the second hydration peak (likely related to slag reaction) to later hydration times, as did substitution of slag by fly ash. Increasing Na2SO4 dose from 4 to 6% did not lead to further acceleration of hydration or improved strength. T2 - 3rd RILEM Spring Convention and Conference (RSCC 2020) CY - Guimarães, Portugal DA - 10.03.2020 KW - Hybrid cements KW - Alkali-activated materials KW - Calorimetry KW - Early hydration PY - 2021 SN - 978-3-030-76550-7 DO - https://doi.org/10.1007/978-3-030-76551-4_20 SP - 217 EP - 226 PB - Springer CY - Cham AN - OPUS4-53071 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Law, D. W. A1 - Sturm, Patrick A1 - Gluth, Gregor A1 - Gunasekara, C. ED - Valente, I. B. ED - Ventura Gouveia, A. ED - Dias, S. S. T1 - Effect of Curing Temperature on the Alkali Activation of German Brown Coal Fly Ash N2 - Due to environmental concerns regarding the use of Portland cement as the principal binder material in concrete and mortar it is imperative to identify alternative materials that could reduce the carbon footprint of the construction industry. One alternative to address these issues is the use of alkali activated materials, in particular, when based on waste streams that currently have no or only limited industrial application. This paper reports a preliminary study into the synthesis of geopolymer mortar utilizing Brown Coal Fly Ash. The ash had a CaO content of ~39%, indicating that synthesis at ambient or low temperature may be feasible. The paper reports initial trials on the effect of curing temperature, ambient to 120 °C, on the mechanical properties of the mortars produced. The results showed that ambient cured mortar achieved a compressive strength of 6.5 MPa at 3 days. A curing temperature of 60 °C gave the optimum results with a compressive strength of almost 20 MPa and a flexural strength of 3.5 MPa obtained. T2 - 3rd RILEM Spring Convention and Conference (RSCC 2020) CY - Guimarães, Portugal DA - 10.03.2020 KW - Alkali-activated materials KW - Brown Coal Fly Ash KW - Lignite Coal PY - 2021 SN - 978-3-030-76550-7 SN - 978-3-030-76551-4 DO - https://doi.org/10.1007/978-3-030-76551-4_7 SP - 69 EP - 77 PB - Springer CY - Cham AN - OPUS4-53072 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schmidt, Wolfram T1 - Potentials for the use of renewable and recyclable materials and how they can be incorporated in the supply stream N2 - Concrete is a major contributor to global energy demand and CO2-emissions, necessitating mitigation strategies. Utilising bio-based resources like polysaccharides, pozzolanic ashes from agricultural waste, and bio-based fibres and aggregates can reduce carbon footprints. However, implementation is hindered by standards favouring scarce and traditionally European materials like fly ash and slag. This highlights the need to diversify resource streams to benefit the global South's abundance of bio-based resources and arable land. An inclusive approach recognizing bio-based resources is required through innovation and regional adaptation. T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM Green Intelligent Building CY - Berlin, Germany DA - 16.10.2024 KW - Renewable and recyclabe materials KW - Cement KW - Concrete KW - Climate KW - Carbon footprint KW - Bio-based resources KW - Bio-char PY - 2024 AN - OPUS4-61801 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Zhang, K. A1 - Schmidt, Wolfram A1 - Mezhov, Alexander T1 - Influence of the hydroxypropylation of starch on its performance as viscosity modifying agent N2 - Synopsis: Starch is a commonly used viscosity modifying agent (VMA). The performance of starch as VMA depends on its origin (e.g. potato, corn, cassava, etc.) and corresponding molecular properties, such as molecular weight, ratio between amylose and amylopectin etc. Depending upon the application, the efficiency of starch can be enhanced by hydroxypropylation. The maximum degree of substitution (DoS) cannot be greater than 3.0, which is the number of hydroxy groups per glucose monomer in the polymer. In the current research three potato starches exhibiting the DoS of 0.4, 0.6 and 0.8 were utilised. The influence of the modified starch on the rheological properties and hydration of cement paste, as well as the viscosity of the pore solution were investigated. Our findings show that the starch with the highest DoS increases the dynamic yield stress the most, while the plastic viscosity is less dependent on the DoS. Additionally, starch with the highest DoS retards hydration to lower degree than other starches. T2 - 13th International Conference on Superplasticizers and Other Chemical Admixtures in Concrete CY - Milan, Italy DA - 10.07.2022 KW - Potato starch KW - Rheological KW - Cement hydration KW - Pore solutions PY - 2022 DO - https://doi.org/10.14359/51736074 VL - 354 SP - 209 EP - 218 PB - ACI Special Publications AN - OPUS4-58320 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schmidt, Wolfram A1 - Olonade, K. A. A1 - Mbugua, R. N. A1 - Lenz, F. J. A1 - Tchetgnia Ngassam, I. T1 - Bio-Based Rheology Modifiers for High Performance Concrete – Possible Modes of Actions and Case Study for Cassava Starch in West Africa N2 - Polymers that help tailoring rheological properties during the casting process have become inevitable constituents for all kinds of high-performance concrete technologies. Due to lacking industries, these typically crude-oil based admixtures are not readily available in many parts of the world, which limits the implementation of more sustainable high-performance construction technologies in these regions. Alternative polymers, which often demand for less processing, can be derived from local plant-based resources. The paper provides experimental data of flow tests of cement pastes with polysaccharides from Triumfetta pendrata A. Rich, acacia gum and cassava without and in the presence of polycarboxylate ether superplasticizer. The flow tests are amended by observations of the zeta potentials and the hydrodynamic diameters in the presence of and without calcium ions in the dispersion medium. The results show that in the presence of and without calcium ions all polysaccharides provide negative zeta potentials, yet, they affect flowability and thixotropy in different ways. Cassava starch, acacia gum, and the gum of Triumfetta pendrata A. Rich qualified well for robustness improvement, strong stiffening, and additive manufacturing, respectively. The reason for the different effects can be found in their average sizes and size distribution. Due to the promising results, a flow chart for local value chains is derived on the example of yet unused cassava wastes, which can be converted in parallel. T2 - 3rd International Conference on the Application of Superabsorbent Polymers CY - Skukuza, South Africa KW - Admixtures KW - Polysaccharides KW - Rheology KW - Thixotropy KW - Concrete PY - 2020 SN - 978-3-030-33341-6 SN - 978-3-030-33342-3 DO - https://doi.org/10.1007/978-3-030-33342-3_17 SP - 158 EP - 166 PB - Springer AN - OPUS4-58404 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bäßler, Ralph T1 - Entwicklung einer Prüfmethode zur Bewertung der Materialbeständigkeit von Bauteilen in Mitteldestillatanwendungen N2 - Im DGMK-Projekt 780 wurde eine forcierte Prüfmethode entwickelt zur Bestimmung der Beständigkeit von metallenen Werkstoffen gegenüber Brennstoffen aus Mitteldestillaten und Gemischen aus Mitteldestillat und paraffinischen Kohlenwasserstoffen, die jeweils Fettsäuremethylester (FAME) als biogene Komponente enthalten. Bei der Prüfmethode werden Proben des Werkstoffes in einem speziellen Prüfmedien ausgelagert. Die Zusammensetzung von zwei Prüfmedien wurde im Vorhaben erarbeitet. Die Prüfmedien decken für den FAME-Anteil einen Bereich von bis zu 20 % (V/V) ab. Die Auslagerung kann bei geringem Aufwand unter Atmosphärendruck durchgeführt werden. Die Eignung einer Auswahl von metallenen Werkstoffen und Polymerwerkstoffen, die für Versorgungsanlagen für Mitteldestillat relevant sind, wurde durch Auslagerung in folgenden nicht gealterten Brennstoffen bestimmt: Heizöl EL schwefelarm (B0), Heizöl EL schwefelarm mit 20 % (V/V) FAME (B20), FAME (B100) und hydriertes Pflanzenöl (HVO). Die Temperatur bei der Auslagerung betrug 50 °C für die metallenen Werkstoffe und 40 °C und 70 °C für die Polymerwerkstoffe. Die Ergebnisse der Beständigkeitsbewertung wurden in Beständigkeitslisten zusammengefasst. Die mit dem B20 erhaltenen Werkstoffbeständigkeiten gelten generell für Gemische aus Heizöl EL schwefelarm und FAME mit einem FAME-Gehalt bis zu 20 % (V/V). Sie sind auch auf Gemische aus Dieselkraftstoff und FAME mit einem FAME-Gehalt bis 20 %(V/V) übertragbar. Die forcierte Prüfmethode kann insbesondere KMUs bei der Weiterentwicklung von bestehenden Produkten und der Entwicklung von neuen Produkten als ein kostengünstiger Schnelltest zur Überprüfung der Werkstoff- und Bauteilbeständigkeit gegenüber Mitteldestillaten mit hohem FAME-Anteil dienen. Sie kann für die Hersteller die Sicherheit erhöhen, dass Bauteile die Freigabeprüfungen der Bauaufsicht bestehen, wobei die Freigabe aber nur für Deutschland gültig ist. Die Erkenntnisse des Forschungsvorhabens können in eine harmonisierte Europäischen Norm für alternative Brenn- und Kraftstoffe einfließen. Diese ist für die Bauteilhersteller die Voraussetzung für die Erschließung des europäischen Marktes. T2 - Sitzung des DGMK-Fachausschusses "Brennstoffe" CY - Online Meeting DA - 22.09.2020 KW - Korrosion KW - Biobrennstoff KW - Heizöl KW - FAME PY - 2020 AN - OPUS4-51300 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Weltschev, Margit T1 - Compatibility of polymers with aged heating oil containing 10 % and 20 % biodiesel under static conditions N2 - Biodiesel is viewed as a major source of energy. In areas such as the European Un-ion, where 80 % of the oil-based fuel is imported, there is also the desire to reduce dependence on external oil supplies. Materials compatibility is a major concern whenever the fuel composition is changed. The question arises of whether polymeric materials are resistant to heating oil with 20 % biodiesel (B20) in comparison to pure heating oil. The polarity of biodiesel increases its solvency and facilitates permeation and extrac-tion. Solvation, swelling and/or extraction lead to changes in the physical properties. Extraction alters the fuel chemistry. These chemical changes could also accelerate the degradation (hydrolysis and oxidation) of the polymeric material with the loss of additives and stabilizers. Exposure tests to determine the resistance of polymers frequently used for compo-nents in middle distillate facilities, such as ACM, FKM, HNBR, PA, PE, POM, PUR and PVC in heating oil and a blend of heating oil and 20 % biodiesel (B20) were al-ready performed. The objective of this research was to determine the resistance of these polymers in 8-year aged heating oil blend B10 and 1-year aged blend B20 at 40 °C. Mass, tensile strength, breaking elongation and Shore hardness A (D) of the test specimens were determined before and after exposure for 84 (42) days in the test fuels under static conditions. There is not determined a threshold for the reduction in tensile properties and Shore hardness in the international standards. Therefore, a threshold of 15 % was deter-mined for the evaluation of the compatibility. A significant reduction in Shore hardness was determined after exposure of ACM and PUR test specimens in 1-year aged B20. The tensile strength of PUR test specimens in 1-year aged B20 was reduced by more than 50 %, and the breaking elongation by more than 30 %. A decrease in breaking elongation was measured for POM test specimens after ex-posure to 1-year aged B20 by 25 % (limited resistance). 8-year aged B10 had a stronger effect than 1-year aged B20 on the polymers. ACM test specimens were softened by B10 resulting in a drop of Shore hardness by over 20 %. B10 reduced tensile strength and breaking elongation of PUR test specimens by over 50 %. In contrast, the breaking elongation of POM was increased by over 270 %. It can be concluded that the polymers HNBR, FKM, PA6, PE and PVC are resistant in 1-year aged B20 whereas ACM and POM are limited resistant. PUR is not re-sistant. HNBR, FKM, PA6, PE and PVC are resistant in 8-year aged B10, whereas PUR and POM are not resistant, and ACM just limited resistant. T2 - EUROCORR 2020 CY - Online meeting DA - 07.09.2020 KW - Aged heating oil with 10% and 20% biodiesel KW - Resistance of polymers KW - Tensile properties KW - Shore hardness PY - 2020 AN - OPUS4-51240 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rütters, H. A1 - Fischer, S. A1 - Le, Quynh Hoa A1 - Bettge, Dirk A1 - Bäßler, Ralph A1 - Maßmann, J. A1 - Ostertag-Henning, C. A1 - Lennard Wolf, J. A1 - Pumpa, M. A1 - Lubenau, U. A1 - Knauer, S. A1 - Jaeger, P. A1 - Neumann, A. A1 - Svensson, K. A1 - Pöllmann, H. A1 - Lempp, C. A1 - Menezes, F. A1 - Hagemann, B. T1 - Towards Defining Reasonable Minimum Composition Thresholds – Impacts of Variable CO2 Stream Compositions on Transport, Injection and Storage N2 - The collaborative project “Impacts of impurities in CO2 streams captured from different emitters in a regional cluster on transport, injection and storage (CLUSTER)” aimed to set up recommendations on how to define “reasonable minimum composition thresholds” that CO2 streams should meet when accessing CO2 transport pipeline networks. Within CLUSTER, we investigated potential impacts of CO2 streams with different and temporally variable compositions and mass flow rates along the whole CCS chain. Investigations included, amongst others, impacts on: • corrosion of pipeline steel, • pipeline network design and related transport costs, • alteration of well bore cements, • pressure development and rock integrity, • geochemical reactions, and • petrophysical and geomechanical rock properties. All investigations are based on a generic CCS chain scenario. In this scenario, CO2 streams are captured from a spatial cluster of eleven emitters and collected in a regional pipeline network. Emitters comprise seven fossil fuel-fired power plants equipped with different capture technologies, two cement plants, one refinery and one integrated iron and steel plant. In total, 19.78 Mio t CO2 (including impurities) are captured in the emitter cluster annually. The combined CO2 stream is transported in a trunk line with a length of 400 km (100 km of these offshore) and is injected into five generic storage structures. The storage reservoirs are saline aquifers of the Buntsandstein. The investigations revealed beneficial and deteriorating impacts of different impurities and combinations thereof. Overall, no fundamental technical obstacles for transporting, injecting and storing CO2 streams of the modelled variable compositions and mass flow rates were observed. Based on the results, the CLUSTER project team recommends not to define “minimum composition thresholds” for CO2 streams as strict threshold values for each individual impurity in the stream. Instead, CO2 stream compositions and variabilities for specific CCS projects should be constrained with regard to a set of parameters including i) the overall CO2 content, ii) maximum contents of relevant impurities or elements, iii) acceptable variability of CO2 stream composition, and iv) impurity combinations to be avoided. T2 - The 15th Greenhouse Gas Control Technologies Conference CY - Online meeting DA - 15.03.2021 KW - Corrosion KW - Impurities KW - CO2 quality KW - Pipeline network KW - Whole-chain CCS scenario KW - Recommendations PY - 2021 DO - https://doi.org/10.2139/ssrn.3816427 SP - 1 EP - 18 PB - Elservier AN - OPUS4-52940 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - RPRT A1 - Ackermann, H. A1 - Pötzsch, Sina A1 - Weltschev, Margit A1 - Bäßler, Ralph A1 - Plum, W. T1 - Entwicklung einer Prüfmethode zur Bewertung der Materialbeständigkeit von Bauteilen in Mitteldestillatanwendungen N2 - Im Vorhaben wurde eine forcierte Prüfmethode zur Bestimmung der Beständigkeit von metallenen Werkstoffen gegenüber Brennstoffen aus Mitteldestillaten und Gemischen aus Mitteldestillat und paraffinischen Kohlenwasserstoffen, die jeweils Fettsäuremethylester (FAME) als biogene Komponente enthalten, entwickelt. Bei der Prüfmethode werden Prüfkörper des jeweiligen Werkstoffes in speziellen Prüfmedien ausgelagert. Die Zusammensetzung von zwei Prüfmedien wurde im Vorhaben erarbeitet. Diese Prüfmedien erfassen die Effekte der Alterung des FAME, die zu erwarten sind, wenn der Brennstoff länger als 2 Jahre im Feld lagert. Sie decken den Bereich bis 20 % (V/V) FAME-Anteil ab. Die Auslagerung kann bei geringem Aufwand unter Atmosphärendruck durchgeführt werden. Die Eignung einer Auswahl von metallenen Werkstoffen und Polymerwerkstoffen, die für Versorgungsanlagen für Mitteldestillat relevant sind, wurde durch Auslagerung in folgenden nicht gealterten Brennstoffen bestimmt: Heizöl EL schwefelarm (B0), Heizöl EL schwefelarm mit 20 % (V/V) FAME (B20), FAME (B100) und hydriertes Pflanzenöl (HVO). Die Werkstoffe wurden auch in einem 1 Jahr gealterten B20 und einem 8 Jahre gealtertem B10 ausgelagert. Die Temperatur bei der Auslagerung betrug 50 °C für die metallenen Werkstoffe und 40 °C und 70 °C für die Polymerwerkstoffe. Die Ergebnisse der Beständigkeitsbewertung wurden in Beständigkeitslisten zusammengefasst. Die mit B20 erhaltenen Bewertungen gelten generell für Gemische aus Heizöl EL schwefelarm und FAME mit einem FAME-Gehalt bis 20 % (V/V). Sie sind auch auf Gemische aus Dieselkraftstoff und FAME mit einem FAME-Gehalt bis 20 %(V/V) übertragbar. Die forcierte Prüfmethode kann insbesondere KMUs bei der Weiterentwicklung von bestehenden Produkten und der Entwicklung von neuen Produkten als ein kostengünstiger Schnelltest zur Überprüfung der Werkstoff- und Bauteilbeständigkeit gegenüber Mitteldestillaten mit hohem FAME-Anteil dienen. Sie kann für die Hersteller die Sicherheit erhöhen, dass Bauteile die Freigabeprüfungen der Bauaufsicht bestehen, wobei die Freigabe jedoch nur für Deutschland gültig ist. Die Erkenntnisse des Forschungsvorhabens können in eine harmonisierte Europäische Norm für alternative Brenn- und Kraftstoffe einfließen. Diese ist für die Bauteilhersteller die Voraussetzung für die Erschließung des europäischen Marktes.   N2 - Within this project, a forced test method was developed to determine the resistance of metallic materials to middle distillate fuels and mixtures of middle distillate and paraffinic hydrocarbons both with fatty acid methyl ester (FAME) as a biogenic component. In the method, specimens of the material are immersed in special test media. The compositions of two test media were developed within the project. These test media include the influence of aging of the FAME which is to be expected after a storage of the fuel exceeding 2 years in the field. They cover a range of up to 20 % (v/v) FAME content. The exposure test can be carried out at ambient pressure with little effort. Suitability of selected metallic and polymer materials relevant for middle distillate supply systems was determined by exposure to the following non-aged fuels: low-sulfur light fuel oil (B0), low-sulfur light fuel oil with 20 % (v/v) FAME (B20), FAME (B100) and hydrogenated vegetable oil (HVO). The materials were also exposed in the 1-year-aged B20 and 8-year-aged B10. Test temperature was 50 °C for metallic materials and 40 °C and 70 °C for polymers. Resulting materials resistances were summarized in resistance tables. Resistances obtained in B20 are valid for any mixture of low-sulfur light fuel oil and FAME containing up to 20 % (v/v) FAME. They are also transferable to mixtures of diesel and FAME having a FAME content of up to 20 % (v/v). This method with special test media is a cost-effective rapid test for checking resistance of materials to middle distillates having a high FAME content. It can support SMEs manufacturing components for supply systems in further development of existing and new products. It increases the manufacturers' certainty that components will pass approval tests of authorities. Results of this research project can be incorporated into a harmonized European standard for alternative fuels. This is the prerequisite for component manufacturers to access the European market. KW - Heizöl KW - FAME KW - Biobrennstoff PY - 2020 UR - https://dgmk.de/publikationen/ SN - 978-3-947716-14-2 SN - 0937-9762 SP - 1 EP - 153 PB - DGMK CY - Hamburg AN - OPUS4-51110 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Weltschev, Margit A1 - Pötzsch, Sina T1 - Entwicklung einer Prüfmethode zur Bewertung der Materialbeständigkeit von Bauteilen in Mitteldestillatanwendungen N2 - Für Bauteile (Komponenten) von Versorgungsanlagen für flüssige Brenn- und Kraftstoffe muss die Beständigkeit der metallenen Werkstoffe und Polymere nachgewiesen werden. Im Anwendungsfall von Heizöl mit 20 % biogenen Anteilen in Form von Rapsölfettsäuremethylester (FAME, Biodiesel) ist es für eine konservative Beurteilung des Korrosionssystems Werkstoff/Medium/Umgebung wichtig, die Alterungs­effekte des Mediums einzubeziehen. Entwicklung eines Prüfverfahrens für die Untersuchung der Beständigkeit von metallenen Werkstoffen und Polymeren in Heizöl und Heizöl-FAME-Blends, das für eine Vorauswahl der Werkstoffe und zum Nachweis der Beständigkeit im Hinblick auf die bauaufsichtlichen Zulassungsverfahren geeignet ist. Ein Schwerpunkt wird bei den metallenen Werkstoffen auf der Erprobung von Messmethoden liegen, mit denen sich in kurzer Versuchszeit ein Korrosionsangriff detektieren lässt. Metallene Werkstoffe: Weder örtliche Korrosion noch erhöhte Flächenkorrosion (Korrosionsrate:< 0,1 m/Jahr) sind bei den bisher geprüften Werkstoffen: Aluminium, C-Stahl 1.0037, austenitischer CrNi-Stahl 1.4301, Kupfer und Messing in Heizöl und B20 (Heizöl mit 20% Biodiesel) aufgetreten. Diese Werkstoffe sind in den Prüfmedien Heizöl und B20 als beständig zu bewerten. Es wurde keine signifikante Veränderung des pH-Wertes der Prüfmedien gemessen. Polymere: Massebestimmung: Die Prüfkörper der Elastomere ACM, HNBR und PUR sowie in geringerem Maße PE neigten zur Quellung in Heizöl und B20 nach 42 d und 84 d Auslagerung; für PA 6, POM und PVC wurde keine Masseänderung gemessen. Die Masseänderung der Prüfkörper in Heizöl und B20 ist mit Ausnahme von PUR vergleichbar. Bei PE traten Verfärbungen durch die Brennstoffe auf. Zugeigenschaften: ACM, HNBR, PE und PVC sind in Heizöl und B20 beständig, da die Änderung der Zugfestigkeit und der Reißdehnung < 15 % beträgt. PA und POM sind bedingt beständig, da die Änderung der Zugfestigkeit und der Reißdehnung < 30% beträgt. T2 - DGMK-Projekttreffen CY - Rostock, Germany DA - 28.03.2019 KW - Beständigkeitsbewertung KW - Metallene Werkstoffe KW - Polymere KW - Heizöl KW - Heizöl-FAME-Blends PY - 2019 AN - OPUS4-47841 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Pötzsch, Sina T1 - Beständigkeit von Elastomeren bei Einsatz im Heizölgemisch mit 20 % Biodiesel (B20) bei unterschiedlichen Temperaturen unter statischen und verpressten Bedingungen N2 - Aus Rapsöl gewonnener Biodiesel ist eine umweltfreundliche Alternative zu fossilen Energiequellen. In der Europäischen Union, in der 80 % der ölhaltigen Brennstoffe importiert werden müssen, besteht zudem ein Interesse, die Abhängigkeit von exter-nen Ölversorgern zu reduzieren. Bei jeder Veränderung der Zusammensetzung eines Brennstoffs muss auch die Ma-terialverträglichkeit gewährleistet bleiben. Es stellt sich die Frage, ob Elastomere im Vergleich zu reinem Heizöl auch in Heizöl mit 20 % Biodiesel (B20) beständig sind. Die Polarität des Biodiesels erhöht die Quellung und fördert die Permeation und Ex-traktion. Sowohl Quellung als auch Extraktion bedingen Änderungen der physikali-schen Eigenschaften der Elastomere. Extraktion verändert die chemische des Heiz-öls. Diese chemischen Veränderungen können auch den Abbau (Hydrolyse und Oxi-dation) der Polymere durch das Herauslösen von Additiven und Stabilisatoren be-schleunigen. Ziel dieser Arbeit war die Bestimmung der Beständigkeit der Elastomere ACM (Poly-acrylatkautschuk), HNBR (Hydrierter Acrylnitrilbutadienkautschuk), FKM (Fluorkaut-schuk) und PUR (Polyurethan) in Heizöl und im Heizölgemisch B20. Prüfkörper der Elastomere wurden für 42 Tage (Härteprüfung) und 84 Tage (Zugprü-fung) bei 40 °C ausgelagert. Anschließend wurde die Änderung der Masse, Shore Härte A, Zugfestigkeit, und Reißdehnung bezogen auf die Werte vor der Aus-lagerung bestimmt. Die weniger zur Quellung neigenden Elastomere FKM und HNBR wurden zusätzlich bei 70 °C ausgelagert. Um die Elastomere im verpressten Zustand zu testen, wurde der Druckverformungs-rest nach DIN ISO 815 bestimmt. Hierzu wurden zylindrische Prüfkörper aus ACM, HNBR und FKM verpresst und in Heizöl und Heizöl mit 20 % FAME für 3, 7, 14, 28, 56 und 90 Tage bei 40 °C ausgelagert. Anschließend wurde über die Dickenmes-sung der Druckverformungsrest ermittelt. Zum Vergleich wurden Prüfkörper verpresst und ohne Medium bei 40 °C ausgelagert. In den internationalen Normen wurde kein Grenzwert für die Veränderung der Zugei-genschaften und der Härte für eine positive Bewertung der Beständigkeit festgelegt. Deshalb wurde in der BAM ein Grenzwert von 15 % für die Beständigkeitsbewertung herangezogen. Bei 40 °C lag die Änderung der Zugeigenschaften und der Shore Härte von ACM, HNBR und FKM in Heizöl und in B20 unter 15 %. Folglich sind ACM, HNBR und FKM bei 40 °C in Heizöl und in B20 beständig. PUR ist bei 40 °C in Heizöl beständig, je-doch nicht für eine Verwendung in B20 geeignet, da sich die Zugfestigkeit und Reiß-dehnung um 50 % vermindert haben. Bei 70 °C ist FKM in Heizöl und B20 beständig, wohingegen HNBR an seine Einsatz-grenzen gelangt und unbeständig ist, in B20 haben sich die Zugfestigkeit um 40 % und die Reißdehnung um 50 % reduziert. T2 - Merseburger Elastomertage - elastoMER 2019 CY - Merseburg, Germany DA - 25.09.2019 KW - Beständigkeit KW - Heizöl mit 20 % Biodiesel KW - Elastomere KW - Biogene Brennstoffe KW - ACM KW - PUR KW - FKM KW - HNBR PY - 2019 AN - OPUS4-49138 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Weltschev, Margit T1 - Compatibility of polymers with heating oil with 20 % biodiesel at different temperatures under static and compressed conditions N2 - Biodiesel is viewed as a major source of energy. In areas such as the European Union, where 80 % of the oil-based fuel is imported, there is also the desire to reduce dependence on external oil supplies. Materials compatibility is a major concern whenever the fuel composition is changed. The question arises of whether polymeric materials are resistant to heating oil with 20 % biodiesel (B20) in comparison to pure heating oil. The polarity of biodiesel increases its solvency and facilitates permeation and extraction. Solvation, swelling and/or extraction lead to changes in the physical properties. Extraction alters the fuel chemistry. These chemical changes could also accelerate the degradation (hydrolysis and oxidation) of the polymeric material with the loss of additives and stabilizers. The objective of this research was to determine the resistance of frequently used materials for components in middle distillate facilities such as ACM, FKM, HNBR, PA, PE, POM, PUR and PVC in heating oil and heating oil blend B20 for 84 days at 40 °C, and FKM, HNBR, PA, POM, PUR and PVC at 70 °C. Mass, tensile strength, breaking elongation and Shore hardness A (D) of the test specimens were determined before and after exposure for 84 (42) days in the test fuels under static conditions. For the investigations under compressed conditions, the mass and the compression set of FKM test specimens were determined before and after exposure for 3, 7, 14, 28, 56 and 90 days in B20 at 40 °C and 70 °C according to ISO 815-1 “Rubber, vul-canized or thermoplastic - determination of compression set – Part 1: At ambient or elevated temperatures”. There is not determined a threshold for the reduction in tensile properties and Shore hardness in the international standards. Therefore, a threshold of 15 % was determined for the evaluation of the compatibility. The change of tensile strength and breaking elongation of test specimens made of ACM, FKM, HNBR, PA, PE, POM, PUR and PVC exposed to heating oil and the blend B20 was less than 15 % at 40 °C. A maximum reduction in Shore hardness A of 14 % was determined for ACM at 40 °C and for HNBR of 15 % at 70 °C. It can be concluded that ACM, FKM, HNBR, PA, PE, POM, PVC and PUR were resistant in B20 at 40°C. FKM, PA, POM and PVC were evaluated as resistant in heat-ing oil and B20 at 70 °C, HNBR and PUR were not resistant in these fuels at 70°C. Based on the mass increase and compression set values of FKM test specimens it can be stated that FKM is resistant in B20 under compressed conditions at 40 °C and 70 °C. T2 - EUROCORR 2019 CY - Sevilla, Spain DA - 09.09.2019 KW - Heating oil - biodiesel - blend KW - Polymeric materials KW - Compatibility KW - Tensile properties KW - Shore Hardness PY - 2019 AN - OPUS4-49002 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Weltschev, Margit T1 - Compatibility of polymeric materials with heating oil/biodiesel blends at different temperatures N2 - Materials compatibility is a major concern whenever the fuel composition is changed. The question arises of whether polymeric materials are resistant to heating oil with admixtures of 10 % biodiesel (B10) and 20 % biodiesel (B20). The polarity of biodiesel increases its solvency and facilitates permeation and extrac-tion. Solvation, swelling and/or extraction lead to changes in the physical properties and chemical changes of polymeric materials. The objective of this research was to determine the resistance of frequently used sealing materials such as FKM, EPDM, CR, CSM, NBR, IIR, VMQ, FVMQ, PA and PUR in up to four-year aged B10 for 84 days at 20 °C, 40 °C and 70 °C. The polymeric materials: ACM, FKM, HNBR, PA, PE; POM, PUR and PVC were ex-posed to B20 for 84 days at 40°C and 70°C in another research project. Mass, tensile strength, breaking elongation and Shore hardness A (D) of the test specimens were determined before and after the exposure for 84 (42) days in the heating oil blends B10 and B20. There is not determined a threshold for the reduction in tensile properties and Shore hardness in the international standards. Therefore, a threshold of 15 % was deter-mined for the evaluation of the compatibility. Measurements of the variations in mass, tensile properties and Shore hardness after exposure of the polymers in non-aged and aged heating oil B10 showed clearly that FKM, FVMQ and PA were the most resistant materials in B10. The elastomers CR, CSM, EPDM, IIR, NBR and VMQ were generally not resistant to B10. Damage to the materials increased with higher test temperatures and the age of B10. FKM, POM and PVC showed high compatibility in B20 at 40°C and 70 °C. ACM, HNBR and PA were evaluated as resistant in B20 at 40 °C but not at 70°C. T2 - Corrosion 2019 CY - Warsaw, Poland DA - 27.09.2019 KW - Polymers KW - Compatibility evaluations KW - Heating oil with 10% biodiesel KW - Heating oil with 20% biodiesel KW - Tensile properties KW - Shore hardness PY - 2019 AN - OPUS4-48146 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Weltschev, Margit T1 - Compatibility of polymeric sealing materials with biodiesel heating oil blends at different temperatures N2 - Biodiesel is subject to degradation processes like oil and grease. The oxidative degradation products of vegetable oil esters in biodiesel particularly lead to enhanced sedimentation in blended fuels. The polarity of biodiesel increases its solvency and facilitates permeation and extraction. Solvation, swelling and/or extraction lead to changes in the physical properties and chemical changes of polymeric materials. It also accelerates the degradation (hydrolysis and oxidation) of these materials with the loss of additives and stabilizers. The objective of this research was to determine the resistance of frequently used polymeric materials such as ACM, EPDM, FKM, FVMQ, CR, CSM, IIR, HNBR, NBR, PA, PE; POM, PUR, PVC and VMQ in biodiesel and heating oil with 10 %/20 % biodiesel (B10/B20) at 40°C and 70°C. Mass, tensile strength and breaking elongation of the test specimens were determined before and after the exposure for 84 days in the biodiesel heating oil blends. The visual examination of some elastomer test specimens clearly showed the great volume increase until break or partial dissolution. Shore hardness A and D were determined before and after exposure of the test specimens in the biofuels for 42 days. The elastomers CR, CSM, EPDM, IIR, NBR and VMQ were generally not resistant to biodiesel and B10 at 40°C and 70°C. FKM, ACM, HNBR, PA, PE, POM, and PVC showed high compatibility in B10/B20 at 40°C. A lower compatibility was determined for ACM in biodiesel. ACM and HNBR were not resistant in B20 at 70°C. T2 - Biofuels & Bioenergy CY - Rome, Italy DA - 14.10.2019 KW - Heating oil-Biodiesel-Blend KW - Compatibility evaluations KW - Tensile properties KW - Shore hardness PY - 2019 AN - OPUS4-49306 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Pötzsch, Sina T1 - Resistance of metals exposed to heating oil blends with 10 % and 20 % biodiesel (FAME) N2 - In Europe biodiesel gained from rapeseeds are considered as an alternative to common fossil fuels due to its environmental performance and its independence from import of raw materials. Biodiesel is also suitable to serve as blending component to heating oil. In that case, it must be considered that changes of fuel composition might cause material degradation. The objective of this research was to investigate the resistance of metallic materials exposed to heating oil, heating oil blend B20 with 20 % biodiesel and pure biodiesel. Furthermore, the resistance of metals to eight-year aged B10 and six-year aged pure biodiesel was evaluated. Ageing of biodiesel forms acids and water which might propagate metal corrosion. The investigated metals (aluminium, unalloyed steel, austenitic CrNi-steel, copper, die cast zinc and brass) are commonly used for components in middle distillate facilities. According to DIN 50905-4 the immersed metals were exposed in a climate chamber at 50°C for 4 weeks. The metallic materials were evaluated as resistant if the annual corrosion rate due to uniform corrosion remained under 0.1 mm/year and no localized corrosion in the form of pitting occurred. The corrosion rates of the exposed materials stayed far below the limit of 0.1 mm/year for all tested fuels. An exception was die cast zinc ZP0410 in eight-year aged B10; a corrosion rate up to 0.3 mm/year due to uniform corrosion was measured. In no case localized corrosion occurred. Copper and brass caused discolouration of biodiesel from yellow to green. In conclusion, the tested metallic materials were resistant in heating oil, heating oil blend B20 and pure biodiesel at 50 °C. Even the metals exposed to six-year aged biodiesel and eight-year aged B10 showed no uniform or localized corrosion; except for zinc, which was not resistant in eight-year aged B10. T2 - EUROCORR 2019 CY - Sevilla, Spain DA - 09.09.2019 KW - Metals KW - Heating oil KW - Biodiesel KW - RME KW - Corrosion KW - Compatibility KW - FAME PY - 2019 AN - OPUS4-49137 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kemmler, Samuel T1 - Particle resolved simulations of piping erosion in suction bucket foundations N2 - This poster provides an overview of the recent advances in simulating piping erosion during the installation process of a suction bucket foundation. The lattice Boltzmann method is coupled with the discrete element method. Numerical results are presented for three different suction conditions. T2 - 5th International Symposium on Geomechanics from Micro to Macro CY - Grenoble, France DA - 23.09.2024 KW - Suction bucket foundation KW - Coupled fluid-particle simulation KW - Offshore wind support structure KW - High-performance computing PY - 2024 AN - OPUS4-62375 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Seifert, Lando T1 - H2Mare - PtX-Wind: UAP 5.4 BAM Offshore Corrosion - Seawater Laboratory N2 - The lecture will focus on the experimental possibilities in BAM's seawater laboratory at the Eidersperrwerk. In this laboratory, water parameters can be monitored and, for the first time, it is possible to colonise and maintain salt water growth in a corrosion laboratory environment in order to study systems and materials for offshore applications. T2 - Leitprojekt H2Mare Verbundtreffen PtX-Wind & TransferWind CY - Frankfurt am Main, Germany DA - 05.12.2024 KW - Offshore Corrosion KW - Marine Corrosion KW - Corrosion KW - Green Hydrogen PY - 2024 AN - OPUS4-62055 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Seifert, Lando T1 - Das Meerwasserlabor am Eidersperrwerk N2 - Das Meerwasserlabor (Laborcontainer) ist eine Remote-fähiges Elektrochemie-Labor mit entfeuchtungsfähiger Klimatisierung in dem eine Vielfalt an experimentellen Möglichkeiten besteht. Das Alleinstellungsmerkmal ist der Meerwasser-Bypass, durch den eine Besiedlung und Erhalt von Salzwasser- bzw. Brackwasserbewuchs (Bakterien, Algen, Tiere, Pilze, etc.) möglich ist. Der jährliche Verlauf der Meeresumwelt wird dadurch abgebildet. T2 - Leitprojekt H2Mare Verbundtreffen PtX-Wind & TransferWind CY - Frankfurt am Main, Germany DA - 05.12.2024 KW - Offshore Corrosion KW - Marine Corrosion KW - Corrosion KW - Green Hydrogen PY - 2024 AN - OPUS4-62054 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Nikoonasab, Ali A1 - Licht, M. A1 - Weiler, L. A1 - Achenbach, R. A1 - Raupach, M. A1 - Gluth, Gregor T1 - Pore Solution composition of GGBFS-containing cement pastes N2 - Ground Granulated Blast-Furnace Slag (GGBFS), a by-product of the iron-making process, has gained significant attention as a supplementary cementitious material and has become increasingly popular in recent years due to its remarkable properties. GGBFS can significantly reduce the environmental impact of cement production when it comes to building concrete structures. GGBFS can either be blended with ordinary Portland cement (OPC) (up to a 90% replacement), or it can be used in the production of alkali-activated materials (AAMs). However, a comprehensive understanding of the pore solution composition is necessary for understanding various aspects of cementitious materials and their durability, including corrosion behavior, passivation of steel, and resistance to deteriorative processes. In the present work, the pore solutions of seven different GGBFS-containing cements (alkali-activated slag, alkali-activated slag/fly ash blends, a hybrid alkaline cement, CEM III/C, and CEM III/B) were extracted and analysed by inductively coupled plasma-optical emission spectroscopy, ion chromatography, pH, redox potential, and conductivity measurements. For comparison, a Portland cement pore solution was analysed similarly. The Concentrations of reduced sulfur were noteworthy in all GGBFS-containing cements, particularly in alkali-activated cements, where concentrations were notably higher compared to standard cements. The redox potentials of the pore solutions were primarily dictated by the concentrations of reduced sulfur, although other factors may contribute. Additionally, sulfur species in the pore solutions had an impact on pH, electrical conductivity, and other properties pertinent to the corrosion of reinforcements. T2 - RILEM Spring Convention 2024 & Conference on Advanced Construction Materials and Processes for a Carbon Neutral Society CY - Milan, Italy DA - 10.04.2024 KW - GGBFS KW - AAM KW - Sulfide KW - Pore solution composition KW - Redox potential PY - 2024 AN - OPUS4-59960 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Durlo Tambara, Luis Urbano A1 - Dehn, F. A1 - Gluth, Gregor T1 - Effect of alkali-activated concrete composition on carbonation rate under accelerated and natural conditions N2 - While alkali-activated binders offer certain advantages over traditional Portland cement binders, particu¬larly in terms of resistance against chemical attacks and potentially environmental footprint, their degradation mechanisms remain incompletely understood at present, specifically carbonation. Thus, this study investigates the impact of natural and accelerated carbonation (1% and 4% CO2) on three different compositions of alkali-activated concretes: 100% calcined clay (C100) binder, 100% ground blast furnace slag (S100) binder, and a 40% calcined clay and 60% blast furnace slag blend (C40S60). C100 concretes exhibit faster carbonation kinetics, with five times greater natural carbonation depths than S100. This difference diminishes under accelerated carbonation, showing a 1.5 times difference for 1% CO2 and complete carbonation for 4% CO2 at 90 days. The results thus confirm that accelerated carbonation testing of low-Ca alkali-activated concretes yields results that are not representative of natural carbonation. The C40S60 sample demonstrates a carbonation profile similar to a CEM I concrete, i.e., a high carbonation resistance. Microstructure analysis indicates the formation of three polymorphs of calcium carbonate for S100 (calcite, vaterite, and aragonite), with a higher CO2 concentration favouring aragonite over vaterite. C100 exhibits no calcium carbonates; instead, sodium carbonates form, including trona for 4% CO2 and natrite for both accelerated tests. C40S60 shows calcium and sodium carbonates, although to a lesser extent, containing predominantly calcite and minor signals of natrite. Suitable compositions, like C40S60, prove as effective during natural or accelerated carbonation tests as conventional Portland cement concrete. T2 - RILEM Spring Convention 2024 CY - Milan, Italy DA - 10.04.2024 KW - Alkali-activated concrete KW - Carbonation KW - Calcined clay KW - Slag KW - Durability PY - 2024 AN - OPUS4-59915 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bertron, A. A1 - Grengg, C. A1 - Peyre Lavigne, M. A1 - Wack, H. A1 - Gluth, Gregor A1 - Aboulela, A. A1 - Sonois, V. A1 - Mittermayr, F. T1 - Comparative evaluation of laboratory methods for performance assessment of cementitious materials in wastewater networks: Biological and chemical tests versus field exposure N2 - The biodeterioration of concrete elements in sewer systems and their repair is of significant economic and societal concern. However, the available test methods to assess the performance of cementitious materials under the relevant conditions are insufficiently validated. In the present study, two biological test methods and a standardised chemical test were applied to two sewer repair mortars and a reference mortar, and the performances of these materials were compared in a severely deteriorating sewer environment. In both biological tests, the induction period was considerably shorter than that of the field, and time-resolved recording of durability indicators enabled to determine deterioration rates in the steady-state regime, which compared reasonably well with each other and with the behaviour in the sewer environment. The chemical test does not allow to obtain a deterioration rate, and the observed relative performance differences of the mortars deviated from the results of the biological tests. KW - MIC KW - Biodeterioration KW - Sulfuric acid attack KW - Testing KW - Cementitious repair systems PY - 2025 DO - https://doi.org/10.1016/j.cemconres.2024.107741 SN - 0008-8846 SN - 1873-3948 VL - 188 SP - 1 EP - 18 PB - Elsevier Ltd. AN - OPUS4-61857 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Gluth, Gregor T1 - Dauerhaftigkeit von Betonen auf Basis klimafreundlicher Bindemittel N2 - Aus Gründen des Klimaschutzes werden in den kommenden Jahren mehr Zemente mit verringertem Klinkerfaktor und alternative Bindemittel (klimafreundliche Bindemittel) zum Einsatz kommen. Für ihre sichere und zuverlässige Verwendung ist ein umfangreiches Verständnis der Einflüsse auf die Dauerhaftigkeit der aus ihnen hergestellten Betone notwendig. Der vorliegende Beitrag gibt einen kurzen Überblick über einige jüngere Entwicklungen und Forschungsergebnisse auf dem Gebiet. Der Fokus liegt auf Ergebnissen der Arbeiten von Technischen Komitees der RILEM sowie der EFC und eigenen Forschungsergebnissen. T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM Green Intelligent Building CY - Berlin, Germany DA - 16.10.2024 KW - Beton KW - Bindemittel KW - Klimaschonender Zement KW - Bewehrungskorrosion KW - Chlorideindringen KW - Carbonatisierung PY - 2024 AN - OPUS4-61816 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Zinas, Orestis T1 - Stochastic variational Gaussian process for 3D site characterization N2 - This work was presented at the the 2nd Workshop on Future of Machine Learning in Geotechnics (2FOMLIG) & the 5th Machine Learning in Geotechnics Dialogue (5MLIGD), in Chengdu, China. In this study, we propose an efficient multivariate Gaussian process regression model, utilizing the Linear Model of Coregionalization, stochastic variational inference and Dirichlet-based transformations, to jointly model continuous CPT and categorical (USCS) borehole variables. The predictive performance of the model is assessed using a real dataset from a site located in Christchurch, New Zealand. T2 - 2nd Workshop on Future of Machine Learning in Geotechnics (2FOMLIG) & the 5th Machine Learning in Geotechnics Dialogue (5MLIGD) CY - Chengdu, China DA - 11.10.2024 KW - Geotechnical site-characterization KW - Cone Penetration Tests KW - Multivariate Gaussian process regression KW - Categorical borehole data KW - Stratigraphy prediction KW - Linear Model of Coregionalization PY - 2024 AN - OPUS4-61775 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Gluth, Gregor T1 - Alkalisch aktivierte Bindemittel mit hohem Säurewiderstand für die Kanalsanierung N2 - Die biogene Schwefelsäurekorrosion (BSK) von Betonbauteilen in Abwassersystemen verursacht weltweit hohen Reparaturbedarf. Um zukünftigen Reparaturbedarf zu minimieren, werden für Neubau- und Sanierungsmaßnahmen z. T. Materialien mit besonders hohem Widerstand gegen BSK benötigt. Der vorliegende Beitrag beschreibt Forschungen zu alkalisch aktivierten Bindemitteln, die bei geeigneter Formulierung einen hohen Widerstand gegen BSK bzw. Säureangriff aufweisen. Zusätzlich werden jüngste Fortschritte bei der Bewertung von Methoden zur Prüfung des Widerstands gegen BSK dargestellt. T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM Green Intelligent Building CY - Berlin, Germany DA - 16.10.2024 KW - Alkalisch aktivierte Bindemittel KW - Biogene Schwefelsäurekorrosion KW - Säurewiderstand PY - 2024 AN - OPUS4-61747 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ebell, Gino T1 - Corrosion in Marine Environment N2 - The investigation of the corrosivity of atmospheres ia a major target to ensure the durability of metallic structures. Therefore the corrosivity has to be determined and finally, the right material or corrosion protection system has to be chosen.Under marine environments it is a big challange to expose so called exposure racks to carry out those investigation. Together with EnBw we are able to use highly sought-after areas at the offshore plattform OSS for our investigations. T2 - Präsentation Corrosion für Prof. David M. Paterson CY - Berlin, Germany DA - 28.11.2024 KW - Corrosion KW - Wind PY - 2024 AN - OPUS4-61826 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sittner, Jonathan T1 - Calcinierung in der Wirbelschicht: Steigerung der Reaktivität von calcinierten Tonen? N2 - Calcined clays are emerging as sustainable alternatives for cement production due to their potential to reduce carbon footprint and energy consumption. This study investigates the calcination of low-grade kaolinitic clays, using rotary kiln and fluidized bed. The calcined clays from the rotary kiln showed enhanced performance in the cement paste. The fluidized bed method demonstrated the potential for significant energy savings, achieving near-complete dehydroxylation with just 30 minutes of calcination. These findings highlight the promise of fluidized bed calcination for efficient clay activation, though further optimization is needed. T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM Green Intelligent Building CY - Berlin, Germany DA - 16.10.2024 KW - Calcinierung KW - Calciniermethode KW - Wirbelschicht KW - Klinkerersatz PY - 2024 AN - OPUS4-61813 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Franco de Carvalho, J. M. A1 - Defàveri, K- A1 - Castro Mendes, J. A1 - Schmidt, Wolfram A1 - Kühne, Hans-Carsten A1 - Fiorotti Peixoto, R. A. T1 - Influence of particle size-designed recycled mineral admixtures on the properties of cement-based composites N2 - In this work, engineered recycled mineral admixtures were obtained from four different industrial residues: basic oxygen furnace slag, iron ore tailings, quartz mining tailings and quartzite mining tailings. The grinding performance was evaluated in two different programs and the characterization included chemical and mineralogical composition, particle morphology, and physical properties. Performance evaluations were carried out in blended pastes and mortars, including flow properties, hydration kinetics, soundness, pozzolanic activity, and compressive strength. Coarser-than-cement admixtures allowed better flow performance, greater dimensional stability and more economical production, while finer-thancementn admixtures improved mechanical performance by both filler effect and cementing activity. KW - Engineered recycled mineral admixtures KW - Rheology KW - Hydration kinetics KW - Basic oxygen furnace slag KW - Iron ore tailings KW - Mining tailings PY - 2021 DO - https://doi.org/10.1016/j.conbuildmat.2020.121640 SN - 0950-0618 VL - 272 SP - 1 EP - 13 PB - Elsevier Ltd. AN - OPUS4-58255 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Zhang, K. A1 - Mezhov, Alexander A1 - Schmidt, Wolfram T1 - Effect of Polycarboxylate Superplasticizer in Ordinary Portland Cement and Sulfate Resistant Cement N2 - Polycarboxylate superplasticizers (PCE) are the most widely used admixtures in today’s cementitious construction materials. The molecular structure has a decisive influence on the effectiveness of PCE, which also can be tailored to serve in a different cementitious system. The current study investigates the influence of the backbone charge density of PCE on the rheology, hydration kinetics, and adsorption behavior of ordinary Portland cement (OPC) and sulfate-resistant cement (SRC). The results indicate that regardless of the PCE type, OPC requires a higher amount of PCE to be adsorbed to induce changing of rheological parameters and hydration kinetics. Regardless of the cement type, the PCE with a higher charge density exhibits higher adsorption behavior, corresponding to lower viscosity measurement. Compared to OPC, SRC is more sensitive to the introduction of both PCEs and has a lower saturation dosage, indicating that SRC generally provides better workability properties regardless of the PCE. KW - Polycarboxylate superplasticizers (PCE) KW - Sulfate resistant cement (SRC) KW - Rheological KW - Adsorption KW - Cement hydration PY - 2023 DO - https://doi.org/10.1061/JMCEE7.MTENG-15033 SN - 0899-1561 VL - 35 IS - 6 SP - 1 EP - 12 PB - ASCE Libary AN - OPUS4-58244 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Shamsuddoha, Md A1 - Hüsken, Götz A1 - Schmidt, Wolfram A1 - Kühne, Hans-Carsten A1 - Baeßler, Matthias T1 - Long-term mechanical and shrinkage properties of cementitious grouts for structural repair N2 - Grouts have numerous applications in construction industry such as joint sealing, structural repair, and connections in precast elements. They are particularly favoured in rehabilitation of structures due to penetrability and convenience of application. Grouts for repair applications typically require high-performance properties such as rapid strength development and superior shrinkage characteristics. Sometimes industrial by-products referred as supplementary cementitious materials (SCM) are used with neat cement due to their capabilities to provide binding properties at delayed stage. Micro silica, fly ash and metakaolin are such SCMs, those can modify and improve properties of cement products. This study aims at investigating long-term mass loss and linear shrinkage along with long-term compressive and flexural strength for grouts produced from ultrafine cement and SCMs. A series of mixtures were formulated to observe the effect of SCMs on these grout properties. Properties were determined after 365 days of curing at 23oC and 55% relative humidity. The effect of SCMs on the properties are characterised by statistical models. Response surfaces were constructed to quantify these properties in relation to SCMs replacement. The results suggested that shrinkage was reduced by metakaolin, while micro silica and fly ash had positive effects on compressive and flexural strength, respectively. T2 - International Conference on Sustainable Materials, Systems and Structures (SMSS 2019) CY - Rovinj, Croatia DA - 20.03.2019 KW - Grout KW - Long-term shrinkage KW - Micro silica KW - Fly ash KW - Metakaolin PY - 2019 DO - https://doi.org/10.21809/rilemtechlett.2019.82 SN - 2518-0231 VL - 4 SP - 9 EP - 15 PB - RILEM Publications SARL CY - 4 avenue du Recteur Poincaré, 75016 Paris, France AN - OPUS4-48712 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Munsch, Sarah Mandy A1 - Schmidt, Wolfram A1 - Lorenzoni, Renata A1 - Telong, Melissa A1 - Grobla, Lili A1 - Lauinger, Robert A1 - Kruschwitz, Sabine T1 - Investigation of the hydration of clinker‑reduced cementitious binders by 1H NMR relaxometry N2 - In this paper, we demonstrate the value of 1 H NMR relaxometry for studying the hydration of clinker-reduced, climate-friendly cementitious binders. Our study includes white cement (WC), ordinary Portland cement (OPC), and samples incorporating reactive agro-waste based ashes and non-reactive biochars as supplementary cementitous materials (SCM). NMR measurements were performed over a period of up to 120 h during hydration with an echo time of 50 μ s and a relatively large sample size of 20 mL. The results were compared to heat flow calorimetry (HFC) data, and a detailed comparison with literature data was performed for pure OPC and WC. The results show that time-resolved NMR measurements, especially the analysis of individual NMR signal components assigned to defined 1 H reservoirs, are effective for studying hydration processes. They offer insights into the evolution of the microstrucure and specific chemical phases. NMR provides valuable information and serves as a good complement to HFC. The comparison with data obtained with shorter echo times (40 μs or around 15–45 μs with solid echo sequence) on much smaller samples showed almost identical developments with respect to the T2 distributions. For the SCM samples, NMR results indicated partially accelerated hydration processes compared to classical OPC hydration. One SCM sample acted as a highly reactive pozzolan, showing a similar hydration process to OPC with the strongest effect observed when superplasticizer was added. Adding biochar delayed C-S-H gel pore formation but significantly increased capillary pores and even free water, likely due to the sponge-like structure. KW - Nuclear magnetic resonance relaxometry KW - Heat flow calorimetry KW - Cement KW - Hydration KW - Clinker reduction KW - Carbon emission KW - Kinetics PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-630284 DO - https://doi.org/10.1617/s11527-025-02632-x SN - 1871-6873 VL - 58 IS - 137 SP - 1 EP - 23 PB - Springer Nature AN - OPUS4-63028 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Zhang, K. A1 - Mezhov, Alexander A1 - Schmidt, Wolfram T1 - Effect of agitation during the early‑age hydration on thixotropy and morphology of cement paste N2 - The effect of agitation during the earlyage hydration on thixotropy and morphology of cement paste prepared with and without superplasticizers (SP) is investigated by applying penetration test, small amplitude oscillatory shear sweep test (SAOS), isothermal calorimetric test, scanning electron microscopy (SEM) and energy dispersive X-ray analyses (EDX). The results show that the agitation of cement paste during the induction period increases the heat flow rate and destroys existing structures of samples without changing the mineral composition of samples. Yet, if the agitation is applied during the acceleration period, the heat flow rate is significantly lowered and the morphology and mineral composition of samples undergo irreversible change, freshly formed syngenite is destroyed and no longer restored. The penetration force and the static yield stress grow linearly during the induction period and exponentially during the acceleration period. Agitation during the induction period destroys the structure, which causes the static yield stress and the penetration force values becoming nearly equal to zero. However, during the acceleration period, even after agitation the static yield stress and the penetration force exhibit high residual values, which indicates the impact of hydration to the structural build-up. KW - Hydration · Thixotropy KW - Agitation KW - Morphology KW - Structural build-up PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-621189 DO - https://doi.org/10.1617/s11527-024-02504-w VL - 57 SP - 1 EP - 13 PB - Springer Nature Switzerland AG CY - Schweiz AN - OPUS4-62118 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Tlhatlha, Pheladi A1 - Schmidt, Wolfram ED - Rogge, Andreas ED - Meng, Birgit T1 - Policies and codes for sustainable cement and concrete technologies in the Global South N2 - Abstract: This paper explores three primary pathways for improving sustainable cement and concrete technologies: cement production, concrete production, and recycling technologies. It underscores the importance of policy frameworks for transitioning from prescriptive to performance-based standards to foster innovation and support low-carbon technologies, while also addressing the economic, political, and social drivers that shape policy and industry practices. The research questions the replication of Global North standards in the Global South, advocating for locally adapted, unique regional policies. T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM Green Intelligent Building CY - Berlin, Germany DA - 16.10.2024 KW - Sustainable cement KW - Concrete technologies PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-613170 SN - 978-3-9818564-7-7 SP - 114 EP - 122 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-61317 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF ED - Schmidt, Wolfram T1 - ISEE Africa - Innovation, Science, Engineering, Education N2 - Innovation, science and engineering are driving forces to mastering the global challenges of the next decades. The basis is education. ISEE stands for Innovation, Science, Engineering and education. This book summarises the presentations, discussions and Statements that were made during the ISEE-Africa conference held in Nairobi in 2019 from January 30 to February 1. The ISEE conference is a gathering of international researchers, scholars, and students, who came together to discuss jointly relevant topics related to better education for the engineers and architects of the future. Today, we know that the climate change is real. Many regions in the world are already suffering significantly, and the only way for humanity to overcome the challenges is to develop more sustainable technologies to the benefit of the entire global society. However, sustainable technologies require for deeper understanding, more conscious thinking, and smarter engineering. The only way how this can be achieved is to educate the developers, the decision makers, the engineers of tomorrow in a more knowledge driven way, and to equip them with the assertiveness required for the implementation. In this book, topics of construction and sustainable materials are linked to educational challenges. It addresses teachers, academic and political decision makers, and change drivers. The specific objective is to be critical, thought-provoking and inspiring. This way, we do hope that the book can deliver credible solution strategies for enhanced education for a new generation of decision makers with higher awareness of global and environmental challenges as well as innovation potentials. T2 - ISEE Africa - Innovation, Science, Engineering, Education CY - Nairobi, Kenya DA - 30.01.2019 KW - Innovation KW - Science KW - Engineering KW - Materials KW - Environment KW - Sustainability KW - Africa PY - 2019 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-484826 UR - http://isee-africa.com/wp-content/uploads/2019/07/Innovation-Science-Engineering-Education_High-Quality.pdf SN - 978-3-9818564-2-2 SP - 1 EP - 219 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-48482 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Haist, M. A1 - Link, J. A1 - Nicia, D. A1 - Leinitz, Sarah A1 - Baumert, C. A1 - von Bronk, T. A1 - Cotardo, D. A1 - Eslami Pirharati, M. A1 - Fataei, S. A1 - Garrecht, H. A1 - Gehlen, C. A1 - Hauschildt, I. A1 - Ivanova, I. A1 - Jesinghausen, S. A1 - Klein, C. A1 - Krauss, H.-W. A1 - Lohaus, L. A1 - Lowke, D. A1 - Mazanec, O. A1 - Pawelczyk, S. A1 - Pott, U. A1 - Radebe, N. W. A1 - Riedmiller, J. J. A1 - Schmid, H.-J. A1 - Schmidt, Wolfram A1 - Secrieru, E. A1 - Stephan, D. A1 - Thiedeitz, M. A1 - Wilhelm, M. A1 - Mechtcherine, V. T1 - Interlaboratory study on rheological properties of cement pastes and reference substances: comparability of measurements performed with different rheometers and measurement geometries N2 - This paper presents the results of an interlaboratory study of the rheological properties of cement paste and ultrasound gel as reference substance. The goal was to quantify the comparability and reproducibility of measurements of the Bingham parameters yield stress and plastic viscosity when measured on one specific paste composition and one particular ultrasound gel in different laboratories using different rheometers and measurement geometries. The procedures for both in preparing the cement paste and carrying out the rheological measurements on cement paste and ultrasound gel were carefully defined for all of the study’s participants. Different conversion schemes for comparing the results obtained with the different measurement setups are presented here and critically discussed. The procedure proposed in this paper ensured a reasonable comparability of the results with a coefficient of variation for the yield stress of 27% and for the plastic viscosity of 24%, despite the individual measurement series’ having been performed in different labs with different rheometers and measurement geometries. KW - Rheometry KW - Rheology KW - Interlaboratory test KW - Test setup KW - Testing procedure KW - Cement paste KW - Ultrasound gel PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-511220 DO - https://doi.org/10.1617/s11527-020-01477-w SN - 1871-6873 VL - 53 IS - 4 SP - 92 PB - Rilem AN - OPUS4-51122 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Thiedeitz, M. A1 - Schmidt, Wolfram A1 - Härder, M. A1 - Kränkel, T. T1 - Performance of rice husk ash as supplementary cementitious material after production in the field and in the lab N2 - Supplementary cementitious materials (SCM) can reduce the total amount of Portland cement clinker in concrete production. Rice husk ashes (RHA) can be converted from an agricultural by-product to a high-performance concrete constituent due to a high amount of reactive silica with pozzolanic properties if they are burnt under controlled conditions. The way and duration of combustion, the cooling process as well as the temperature have an effect on the silica form and thus, the chemical and physical performance of the RHA. Various studies on the best combustion technique have been published to investigate the ideal combustion techniques. Yet, the process mostly took place under laboratory conditions. Investigating the difference between the performance of RHA produced in a rural environment and laboratory conditions is useful for the assessment and future enhancement of RHA production, and its application both as building material, for example in rural areas where it is sourced in large quantities, and as additive for high performance concrete. Thus, the paper presents a comparison between RHA produced under rudimentary conditions in a self-made furnace in the rural Bagamoyo, Tanzania and under controlled laboratory conditions at the Technical University of Munich, Germany, with different combustion methods and temperatures. In a second step, RHA was ground to reach particle size distributions comparable to cement. In a third step, cement pastes were prepared with 10%, 20% and 40% of cement replacement, and compared to the performance of plain and fly ash blended cement pastes. The results show that controlled burning conditions around 650 °C lead to high reactivity of silica and, therefore, to good performance as SCM. However, also the RHA burnt under less controlled conditions in the field provided reasonably good properties, if the process took place with proper burning parameters and adequate grinding. The knowledge can be implemented in the field to improve the final RHA performance as SCM in concrete. KW - Rice husk ash KW - Agricultural by-product KW - Supplementary cementitious material KW - Waste management KW - Carbon dioxide emissions PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-568953 DO - https://doi.org/10.3390/ma13194319 SN - 1996-1944 VL - 13 SP - 1 EP - 17 PB - MDPI CY - Basel AN - OPUS4-56895 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Lu, Z. A1 - Becker, S. A1 - Leinitz, Sarah A1 - Schmidt, Wolfram A1 - von Klitzing, R. A1 - Stephan, D. T1 - Interaction of Different Charged Polymers with Potassium Ions and Their Effect on the Yield Stress of Highly Concentrated Glass Bead Suspensions N2 - The interaction of different charged polymers, namely anionic polycarboxylate superplasticizer (PCE) and neutral polyethylene glycol (PEG) with potassium ions, and their effect on the yield stress of highly concentrated glass bead suspension (GBS), were studied under different concentrations of potassium ions ([K+]). It was found that, compared to the neutral PEG, the negatively charged PCE can be adsorbed on glass beads (GB), and then decreases the yield stress of GBS. The increasing concentration of free polymer in the interstitial liquid phase with the increased polymer dosage leads to the higher yield stress of GBS, which may be caused by the higher Depletion force. In addition, this effect is also related to the charge density of the polymer and the [K+] in the solution. Along with the increase in [K+], the yield stress of GBS increases significantly with the addition of PCE, but this cannot be observed with PEG, which indicates that potassium ions can interact with negatively charged PCE instead of the neutral PEG. At last, the interparticle Forces between two single GB with adsorbed PCE in solutions containing [K+] and PCE were measured by colloidal probe atomic force microscopy to better understand the interaction of the charged polymer with counterions. KW - Yield stress KW - Free polymer KW - Charge density KW - Depletion force KW - Potassium ions PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-506015 DO - https://doi.org/10.3390/ma13071490 SN - 1996-1944 VL - 13 IS - 7 SP - 1490, 1 EP - 1490, 16 PB - MDPI AN - OPUS4-50601 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Pott, U. A1 - Crasselt, Claudia A1 - Fobbe, N. A1 - Haist, M. A1 - Heinemann, M. A1 - Hellmann, S. A1 - Ivanov, D. A1 - Jakob, C. A1 - Jansen, D. A1 - Lei, L. A1 - Li, R. A1 - Link, J. A1 - Lowke, D. A1 - Mechtcherine, V. A1 - Neubauer, J. A1 - Nicia, D. A1 - Plank, J. A1 - Reißig, S. A1 - Schäfer, T. A1 - Schilde, C. A1 - Schmidt, Wolfram A1 - Schröfl, C. A1 - Sowoidnich, T. A1 - Strybny, B. A1 - Ukrainczyk, N. A1 - Wolf, J. A1 - Xiao, P. A1 - Stephan, D. T1 - Characterization data of reference materials used for phase II of the priority program DFG SPP 2005 “Opus Fluidum Futurum –Rheology of reactive, multiscale, multiphase construction materials” N2 - A thorough characterization of base materials is the prereq- uisite for further research. In this paper, the characterization data of the reference materials (CEM I 42.5 R, limestone pow- der, calcined clay and a mixture of these three components) used in the second funding phase of the priority program 2005 of the German Research Foundation (DFG SPP 2005) are presented under the aspects of chemical and min- eralogical composition as well as physical and chemical properties. The data were collected based on tests performed by up to eleven research groups involved in this cooperative program. KW - Portland cement KW - Limestone powder KW - Calcined clay KW - Sustainable cement KW - DFG SPP 2005 PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-569913 DO - https://doi.org/10.1016/j.dib.2023.108902 VL - 47 SP - 1 EP - 19 PB - Elsevier AN - OPUS4-56991 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Lu, Z. A1 - Haist, M. A1 - Ivanov, D. A1 - Jakob, C. A1 - Jansen, D. A1 - Leinitz, Sarah A1 - Link, J. A1 - Mechtcherine, V. A1 - Neubauer, J. A1 - Plank, J. A1 - Schmidt, Wolfram A1 - Schilde, C. A1 - Schröfl, C. A1 - Sowoidnich, T. A1 - Stephan, D. T1 - Characterization data of reference cement CEM I 42.5 R used for Priority Program DFG SPP 2005 “Opus Fluidum Futurum - Rheology of reactive, multiscale, multiphase construction materials” N2 - A thorough characterization of starting materials is the precondition for further research, especially for cement, which contains various phases and presents quite a complex material for fundamental scientific investigation. In the paper at hand, the characterization data of the reference cement CEM I 42.5 R used within the priority program 2005 of the German Research Foundation (DFG SPP 2005) are presented from the aspects of chemical and mineralogical compositions as well as physical and chemical properties. The data were collected based on tests conducted by nine research groups involved in this cooperative program. For all data received, the mean values and the corresponding errors were calculated. The results shall be used for the ongoing research within the priority program. KW - Portland cement KW - Characterization KW - DFG SPP 2005 PY - 2019 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-500849 DO - https://doi.org/10.1016/j.dib.2019.104699 SN - 2352-3409 VL - 27 SP - 104699 PB - Elsevier Inc. AN - OPUS4-50084 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Lu, Z. C. A1 - Haist, M. A1 - Ivanov, D. A1 - Jakob, C. A1 - Jansen, D. A1 - Schmid, M. A1 - Kißling, P. A. A1 - Leinitz, Sarah A1 - Link, J. A1 - Mechtcherine, V. A1 - Neubauer, J. A1 - Plank, J. A1 - Schmidt, Wolfram A1 - Schilde, C. A1 - Schröfl, C. A1 - Sowoidnich, T. A1 - Stephan, D. T1 - Characterization data of reference cement CEM III/A 42.5N used for priority program DFG SPP 2005 "Opus Fluidum Futurum - Rheology of reactive, multiscale, multiphase construction materials" N2 - Two types of cements were selected as the reference cement in the priority program 2005 of the German Research Foundation (DFG SPP 2005). A thorough characterization of CEM I 42.5 R has been made in a recent publication. In this paper, the characterization data of the other reference cement CEM III/A 42.5 N are presented from the aspects of chemical and mineralogical compositions as well as physical and chemical properties. The characterization data of the slag, which is the second main constituent of this specific cement besides the clinker, are presented independently. For all data received, the mean values and the corresponding errors were calculated. The data shall be used for the ongoing research within the priority program. Also, researchers from outside this priority program can benefit from these data if the same materials are used. KW - Cement KW - Slag KW - Characterization KW - DFG SPP 2005 PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-568980 DO - https://doi.org/10.1016/j.dib.2020.105524 SN - 2352-3409 VL - 30 SP - 1 EP - 14 PB - Elsevier CY - Amsterdam AN - OPUS4-56898 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schmidt, Wolfram ED - Schmidt, Wolfram T1 - Engineering skill requirements to cope with the local and global challenges of the future N2 - In the 21st century, adequate habitat and functioning infrastructure are critical for global societal and economic stability. In addition, growing urbanisation and environmental pollution cause challenges to societies. With increasing velocity, humanity faces that the current way of living is not sustainable. Thus, habitat,infrastructure, urbanisation, environment and sustainability are definitively among the most striking challenges of the 21st century. By consulting, planning, building, maintaining, exploiting and processing of global resources, civil engineers contribute significantly to the existence of these challenges. This is a high responsibility, but due to the heavy involvement, together with adjacent disciplines such as architecture, geosciences, chemistry, physics, environmental sciences and economics, civil engineers also hold the key to mitigate these challenges and provide a brighter global future. Solutions towards greener, more sustainable and economically viable materials do exist, and there is ongoing research on how greener technologies can contribute to better livelihood and economic growth, but their level of implementation is limited, a major reason for which is that these approaches require more fundamental understanding rather than standard application. T2 - ISEE Africa - Innovation, Science, Engineering, Education CY - Nairobi, Kenya DA - 30.01.2019 KW - Civil Engineering KW - Education KW - Sustainability KW - Materials KW - Sciences PY - 2019 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-484895 UR - http://isee-africa.com/wp-content/uploads/2019/07/Innovation-Science-Engineering-Education_High-Quality.pdf SN - 978-3-9818564-2-2 SP - 16 EP - 19 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-48489 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schmidt, Wolfram A1 - Anniser, J. A1 - Manful, K. ED - Schmidt, Wolfram T1 - A sustainability point of view on horizontal and vertical urban growth N2 - In many regions of the world the urbanisation process is accelerating dramatically. This puts pressure on urban planners but also politics to develop strategies for sustainable city growth. With the rapidly increasing demand for living space in urban areas, cities typically grow vertically. This is largely driven by real estate markets and sometimes also by the desire for status symbols. Certainly, vertical urban growth makes sense, when horizontal growth destroys important flora and Fauna (e.g. in rain forest regions), but in many cases vertical growth is result of real-estate business and Expansion limitation due to state or country borders. However, economics and borders are made by humans. They follow human-made rules. Gravity does not. Therefore, from a point of view of sustainable materials and resourceuse, the trending vertical growth of cities may come under scrutiny. The following aspects should be considered, when a decision is taken between a new quarter with limited number of storeys or a new skyscraper. T2 - ISEE Africa - Innovation, Science, Engineering, Education CY - Nairobi, Kenya DA - 30.01.2019 KW - Urbanisation KW - Construction KW - Materials KW - Sustainability KW - Carbon emissions PY - 2019 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-484848 UR - http://isee-africa.com/wp-content/uploads/2019/07/Innovation-Science-Engineering-Education_High-Quality.pdf SN - 978-3-9818564-2-2 SP - 189 EP - 193 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-48484 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schmidt, Wolfram A1 - Radebe, N. ED - Schmidt, Wolfram T1 - Biased by analytical equipment N2 - Today, in scientific events often a certain separation between researchers from laboratories with highly sophisticated equipment and those from less privileged laboratories can be observed. It is not an uncommon situation that results presented at conferences are rubbished or ridiculed because the investigator only used low-end analytical methods. The assessment of the study is then biased based on the equipment, regardless of the actual quality of the study. T2 - ISEE Africa - Innovation, Science, Engineering, Education CY - Nairobi, Kenya DA - 30.01.2019 KW - Analytics KW - Africa KW - Bias KW - Science KW - Research PY - 2019 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-484877 UR - http://isee-africa.com/wp-content/uploads/2019/07/Innovation-Science-Engineering-Education_High-Quality.pdf SN - 978-3-9818564-2-2 SP - 203 EP - 204 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-48487 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Schmidt, Wolfram A1 - Tlhatlha, Pheladi A1 - Obeng, Emmanuel A1 - Tsaku, Mawuli Kwaku A1 - Arthur, Daniel Vincent A1 - Dodoo, Alex ED - Schmidt, Wolfram ED - Tlhatlha, Pheladi T1 - A practical handbook for safe, smart and durable construction in Ghana N2 - The handbook provides practical guidelines for safe, efficient, and effective construction in Ghana, focusing on proper cement use, mixing consistencies and techniques, and environmental protection. It emphasizes quality control, safety in handling construction materials, and the importance of using protective equipment to prevent health hazards. KW - Cement strength classifications KW - Cement mixing ratios KW - Quality control PY - 2025 SN - 978-3-00-083134-8 SP - 1 EP - 35 PB - Ghana Standards Authority (GSA) CY - Accra AN - OPUS4-63641 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Asante, Bright T1 - Influence of aquacultural and agricultural bio-admixtures on cementitious systems N2 - This study investigates the influence of bio-admixtures and bio-ashes from agricultural and aquaculture residues on the workability and strength of cement mortars. While bio-admixtures at low concentrations can enhance the strength, they create similar or lower yield stress as the reference. Bio ash, particularly at a 10% replacement level, maintained good strength, but higher replacements led to significant reductions in both strength and workability. These findings highlight the potential of sustainable construction materials but emphasize the need to balance performance specifications. T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM Green Intelligent Building CY - Berlin, Germany DA - 16.10.2024 KW - Bio-admixtures KW - Cementitious system KW - Sargassum KW - Bio-ashes KW - Yield stress KW - Mortar PY - 2024 AN - OPUS4-61814 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Fini, E. A1 - Kazemi, M. A1 - Poulikakos, L. A1 - de Claville Christiansen, J. A1 - Schmidt, Wolfram A1 - Parast, M. T1 - Toward Sustainability in the Built Environment: An Integrative Approach N2 - The built environment refers to the human-made surroundings within which people reside and work, including buildings, green spaces, streets, urban centers, and critical infrastructure like water and energy networks. This sector holds a pivotal place in the global economy, contributing to approximately 10 percent of the global gross domestic product (Tokede et al., 2022). However, its importance extends far beyond monetary metrics, exerting a profound influence on emissions, resource utilization, and land use transformations across various industries. Notably, this sector stands responsible for more than one-third of global final energy consumption, underscoring its substantial contribution of nearly 40 % to global energy-related greenhouse gas emissions while consuming nearly 60 percent of the world’s total raw materials (Tokede et al., 2022; Thiedeitz et al., 2022). The recent surge in population and urbanization has exacerbated diverse challenges associated with the built environment, such as climate change, pollution, resource depletion, energy inefficiency, and economic instability (Corona et al., 2019). Addressing these multifaceted issues is crucial for fostering sustainability within the built environment. Accelerating the transition toward creating built environments that are circular, well-balanced, inclusive, and resilient, while achieving net� zero emissions, stands as a paramount necessity. This shift is vital to accommodate the future spatial requirements and combat global warming, particularly in light of the rapid urbanization observed in developing nations. One effective strategy for advancing sustainability within the built environment involves material conservation through engineering approaches. A key facet of this approach involves the judicious utilization of engineered waste materials, such as waste plastics, recycled concrete aggregates, and recycled asphalt, among others. These materials can be efficiently employed, accompanied by streamlined resource management practices, to mitigate resource depletion and curtail the release of toxic pollutants typically associated with conventional material production. Furthermore, the customization of design and engineering processes for adsorptive waste materials, exemplified by zeolites, can play a pivotal role in removing gaseous pollutants present in the vicinity. This comprehensive approach is essential for addressing the multifaceted challenges posed by resource scarcity and accumulating waste materials, while simultaneously nurturing sustainable development (Fini et al., 2021). Therefore, the development of practical methods and tools to facil� itate the incorporation of resource conservation and recycling into the establishment of sustainable built environments becomes an urgent imperative. The objective of this special issue is to demonstrate the myriad opportunities for enhancing the sustainability and health of the built environment. This is accomplished through the presentation of novel perspectives, data, models, frameworks, and innovative approaches designed to prevent or mitigate long-term unintended consequences. The overarching goal is to integrate sustainable practices into the fabric of the built environment and actively contribute to the global pursuit of carbon neutrality. By advancing strategies and approaches conducive to sustainable built environments, we strive to deepen our understanding of the most favorable pathways to toward achieving lowcarbon development. Moreover, these endeavors bolster resilience in the face of the profound challenges posed by the rapid onset of climate change. This special issue comprises 21 articles, collectively illuminating the vast potential to enhance the sustainability and health of the built environment. These articles introduce fresh insights, new datasets, nuanced models, and robust frameworks, all dedicated to fortifying the sustainability and health aspects of the built environment. Additionally, this special issue serves as a platform for highlighting innovative approaches geared toward averting or mitigating undesirable long-term consequences. Notably, these articles coalesce around four central themes: (1) Materials Aspects of Sustainability, (2) Management Aspects of Sustainability, (3) Technology Aspects of Sustainability, and (4) Health Aspects of Sustainability. Overall, this special issue reflects the most recent scientific advances in constructing a more sustainable, carbon-neutral future. KW - Recycling KW - Conservation KW - Resources PY - 2024 DO - https://doi.org/10.1016/j.resconrec.2023.107241 SN - 0921-3449 VL - 201 SP - 1 EP - 4 PB - Elsevier B.V. AN - OPUS4-61561 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Crasselt, Claudia T1 - Influence of rheology modifying admixtures on early hydration of cementitious suspensions N2 - The presence of polycarboxylate ether (PCE) based superplasticizers (SPs) has enormous influence on the early hydration of cement. C3A as the most reactive phase of Portland cement plays a significant role in early hydration reactions and affects the rheological performance. Therefore, this talk presents experimental results about the influence of delayed addition of PCEs on the Hydration of alite and C3A-gypsum pastes investigated by isothermal heat flow calorimetry. Complementary in-situ XRD was carried out on C3S and C3A-gypsum pastes to analyze hydration and phase changes related to the addition of PCE. Cement pastes with a delayed addition of PCE showed less retardation compared to simultaneous addition. The alteration caused by PCE is much more pronounced for C3A-gypsum mixes. With a delayed addition of SP, the hydration of C3A is less retarded or even accelerated. It is obvious that there is less retardation the later the addition of SP. Furthermore, the PCE alter the hydration of C3A when added delayed and exhibit changes in kinetics and Hydration rates. XRD results showed that more C3A is dissolved in the presence of PCE. Also, the gypsum depletion occurs earlier in the presence of PCE and even faster with delayed addition. Without PCE AFm starts to form just after the gypsum depletion. However, in the presence of PCE AFm already starts to form at the beginning of the hydration. Due to the faster gypsum depletion in the presence of PCE, also the transformation from ettringite into AFm begins earlier, but takes longer as without SP. T2 - 15th International Congress on the Chemistry of Cement CY - Prague, Czech Republic DA - 16.09.2019 KW - Cement KW - Alite KW - C3S KW - C3A KW - Early hydration KW - Polycarboxylate ether (PCE) KW - Delayed addition PY - 2019 AN - OPUS4-49103 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schmidt, Wolfram T1 - Effects and potentials of plant based chemical admixtures on the performance of cementitious construction materials N2 - While today, engineers can choose from a wide range of rheology modifying admixtures, in some parts of the world, these are difficult to access, due to their complex processing. However, alternatives can be bio-based polymers such as polysaccharides from various sources. These are easily accessible all over the world, do not demand for complicated processing, and typically they are more sustainable than many established materials, which are crude oil-based. The paper presents the effects of acacia gum, cassava starch and the gum of triumfetta pendrata A. Rich on the rheological performance of cementitious systems. It is shown that acacia gum can be as efficient as polycarboxylate based superplasticisers, cassava starch can reduce the yield stress slightly with little effect on the plastic viscosity, and the gum of triumfetta pendrata A. Rich increases the thixotropy of cement pastes with plasticizing polymers significantly. T2 - International Conference on Sustainable Materials, Systems and Structures (SMSS 2019) CY - Rovinj, Croatia DA - 20.03.2019 KW - Polysaccharides KW - Rheology KW - Cement KW - Chemical admixtures KW - Bio-based concrete PY - 2019 AN - OPUS4-47675 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hüsken, Götz T1 - Long-term mechanical and shrinkage properties of cementitious grouts for structural repair N2 - Grouts are particularly favoured in rehabilitation of structures due to penetrability and convenience of application. Grouts for repair applications typically require high-performance properties such as rapid strength development and superior shrinkage characteristics. Sometimes industrial by-products referred as supplementary cementitious materials (SCM) are used with neat cement due to their capabilities to provide binding properties at delayed stage. Micro silica, fly ash and metakaolin are such SCMs, those can modify and improve properties of cement products. This study aims at investigating long-term mass loss and linear shrinkage along with long-term compressive and flexural strength for grouts produced from ultrafine cement and SCMs. A series of mixtures were formulated to observe the effect of SCMs on these grout properties. Properties were determined after 365 days of curing at 23 °C and 55% relative humidity. The effect of SCMs on the properties are characterised by statistical models. Response surfaces were constructed to quantify these properties in relation to SCMs replacement. The results suggested that shrinkage was reduced by metakaolin, while micro silica and fly ash had positive effects on compressive and flexural strength, respectively. T2 - International Conference on Sustainable Materials, Systems and Structures (SMSS 2019) CY - Rovinj, Croatia DA - 20.03.2019 KW - Grout KW - Long-term shrinkage KW - Micro silica KW - Fly ash KW - Metakaolin PY - 2019 AN - OPUS4-47625 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Govin, A. A1 - Bartholin, M.-C. A1 - Schmidt, Wolfram A1 - Grosseau, P. T1 - Combination of superplasticizers with hydroxypropyl guar, effect on cement-paste properties N2 - Viscosity-modifying agent (VMA) are used in several applications of concrete, such as underwater concrete, Self-Compacting Concrete (SCC) or Self-Levelling Underlayments (SLU) in order to improve the washout resistance and the stability. The study focuses on the modifications of cement pastes properties implied when a VMA (hydroxypropyl guars or HPG) and a superplasticizer are introduced together. For reaching this objective, two chemically different polycarboxylate-based superplasticizers (PCE) and two HPGs exhibiting different molar substitution ratios (MSHP), were studied. A method, combining total organic carbon and size exclusion chromatography, was developed in order to quantify the adsorption of the both admixtures. The adsorption of HPGs appears being significantly lowered by the presence of PCE, while only the adsorption of the less charged PCE is slightly affected by the HPG. As consequence, strong modifications of the rheological properties of cement pastes were noticed when HPG and PCE are combined. The desorption of HPG leads to higher yield stress and residual viscosity than with PCE alone. KW - Pore solution KW - Admixture KW - Rheology KW - Adsorption KW - Polymers PY - 2019 DO - https://doi.org/10.1016/j.conbuildmat.2019.04.137 VL - 215 SP - 595 EP - 604 PB - Elsevier Ltd. AN - OPUS4-49298 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CHAP A1 - Becker, S. A1 - Lu, Z. A1 - Leinitz, Sarah A1 - Schmidt, Wolfram A1 - Stephan, D. A1 - von Klitzing, R. ED - Mechtcherine, V. ED - Khayat, K. ED - Secrieru, E. T1 - Particle Interactions in Silica Systems in Presence of Superplasticizer N2 - The flowability of cement paste is of great importance in today’s construction industry and is influenced by additives such as superplasticizers (SP). One type of SPs are polycarboxylate ether type SPs. These additives electrostatically bind with the negatively charged carboxylic groups at the backbone to the positively charged clinker phases. To model positively charged clinker phases with adsorbed SP, silicon Wafers are pre-coated with cationic polyethylenimine (PEI) and SP is adsorbed onto the coated surface (Si/PEI/SP). Two different polycarboxylate ether type (PCE) SP are compared – one for ready-mix concrete and one for precast concrete. In this preliminary study the interaction forces between Si/PEI/SP surface and a silica microsphere (colloidal probe) are investigated under mild physico-chemical conditions (pH *6, ion concentration <10−5 M) using Colloidal Probe Atomic Force Microscopy (CP-AFM). The interaction force between the model surfaces is attractive for low concentration of SP. The force changes from attractive to repulsive by increasing amount of SP. The force upon approach reveals a biexponential behavior. The exponential decay at large and short surface separations are attributed to electrostatic and steric interactions, respectively. The steric forces of the SP for ready-mix concrete show a steeper onset than the SP for precast concrete. The quantification of these interaction forces will be compared to rheological measurements of similar systems. Furthermore, the parameters will be changed to better approach the conditions in real systems, i.e. higher pH and ionic strength. This helps to understand how the forces on the nanoscale influence the macroscopic rheology. KW - Interfacial forces KW - Silica beads KW - Superplasticizer KW - AFM PY - 2019 SN - 978-3-030-22565-0 DO - https://doi.org/10.1007/978-3-030-22566-7 SN - 2211-0844 VL - 23 SP - 571 EP - 579 PB - Springer ET - 1 AN - OPUS4-49183 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Crasselt, Claudia A1 - Schmidt, Wolfram A1 - Sturm, Heinz T1 - Influence of rheology modifying admixtures on early hydration of cementitious suspensions N2 - The presence of polycarboxylate ether (PCE) based superplasticizers (SPs) has enormous influence on the early hydration of cement. C3A as the most reactive phase of Portland cement plays a significant role in early hydration reactions and affects the rheological performance. Therefore, this paper presents experimental results about the influence of delayed addition of PCEs on the Hydration of cement and C3A-gypsum pastes investigated by isothermal heat flow calorimetry. Complementary in-situ XRD was carried out on C3A pastes to analyze hydration and phase changes related to the addition of PCE. Cement pastes with a delayed addition of PCE showed less Retardation compared to simultaneous addition. The alteration caused by PCE is much more pronounced for C3A-gypsum mixes. With a delayed addition of SP, the hydration of C3A is less retarded or even accelerated. It is obvious that there is less retardation the later the addition of SP. Furthermore, the PCE alter the hydration of C3A when added delayed and exhibit changes in kinetics and hydration rates. XRD results showed that more C3A is dissolved in the presence of PCE. Also, the gypsum depletion occurs earlier in the presence of PCE and even faster with delayed addition. Without PCE AFm starts to form just after the gypsum depletion. However, in the presence of PCE AFm already starts to form at the beginning of the hydration. Due to the faster gypsum depletion in the presence of PCE, also the transformation from ettringite into AFm begins earlier, but takes longer as without SP. T2 - 15th International Congress on the Chemistry of Cement CY - Prague, Czech Republic DA - 16.09.2019 KW - Cement KW - C3A KW - Early hydration KW - Polycarboxylate ether (PCE) KW - Delayed addition PY - 2019 SP - 1 EP - 8 AN - OPUS4-49104 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CHAP A1 - Lu, Z. A1 - Becker, S. A1 - Leinitz, Sarah A1 - von Klitzing, R. A1 - Schmidt, Wolfram A1 - Stephan, D. ED - Mechtcherine, V. ED - Khayat, K. ED - Secrieru, E. T1 - Rheological properties of silica beads in the presence of different polymers and electrolyte N2 - Properties of interstitial liquid phase in cement paste, including the species and concentrations of polymers and ion etc., play an important role for the rheological properties of cementitious materials. In order to better understand their effect, an inert model substance, spherical silica beads (SBs) with defined surface and granulometry were used in the presence of electrolytes (CaCl2) and/or different polymers, including polycarboxylate superplasticizer (PCE) and polyethylene glycol (PEG). It was found the presence of Ca2+ greatly increases the viscosity and yield stress of silica beads paste (SBP), which is proportional to the [Ca2+]. For the effect of PCE, the addition of PCE is beneficial to the flowability of SBP, but a high dosage of PCE leads to a reversal effect. Furthermore, the yield stress firstly increases and then decreases with increasing [Ca2+] under the same dosage of PCE. The addition of PEG always increases the yield stress of SBP, regardless of the ion concentration and the presence or not of PCE. KW - Rheological properties KW - Ions KW - Superplasticizer KW - Silica beads PY - 2019 SN - 978-3-030-22565-0 SN - 978-3-030-22566-7 DO - https://doi.org/10.1007/978-3-030-22566-7_72 SN - 2211-0844 VL - 23 SP - 619 EP - 627 PB - Springer ET - 1 AN - OPUS4-49185 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CHAP A1 - Leinitz, Sarah A1 - Lu, Z. A1 - Becker, S. A1 - Stephan, D. A1 - von Klitzing, R. A1 - Schmidt, Wolfram ED - Mechtcherine, V. ED - Khayat, K. ED - Secrieru, E. T1 - Influence of different accelerators on the rheology and early hydration of cement paste N2 - Special applications like pumping, spraying or printing of concrete require the precise adjustment of very specific rheological properties at different time steps during the casting process. Superplasticizers such as polycarboxylate ethers (PCE) can be used to obtain the required flowability, which, possibly in combination with additional rheology modifying admixtures, generate the required specified consistency. However, after the application, the concrete should change the rheological properties immediately in order to avoid deformations at rest. Therefore, the use of accelerators can be effective. Accelerators influence the hydration of cementitious materials, and thus the rheological properties over the course of time and the setting. In this paper, the influence of different accelerators on the rheology and early hydration of cement paste as well as the interaction of accelerator and PCE are presented. Methods like rheometry, needle penetration tests and practical Tests like spread flow were applied. The used accelerators showed accelerating behavior on the cement pastes without and in the presence of PCE. At the same time an influence on the rheology could be observed. This effect was less in the mixes with PCE, especially at the highest water/cement ratio (w/c). KW - Rheology KW - Cement paste KW - Accelerator KW - Superplasticizer KW - Setting PY - 2019 SN - 978-3-030-22565-0 DO - https://doi.org/10.1007/978-3-030-22566-7 SN - 2211-0844 VL - 23 SP - 106 EP - 115 PB - Springer ET - 1 AN - OPUS4-49139 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Mezhov, Alexander A1 - Zhang, K. A1 - Schmidt, Wolfram T1 - Interactions of Biobased Rheology Modifying Agents with Superplasticizer in Cement Paste N2 - Organic admixtures are an indispensable component of modern concrete. Thus, their purposeful application is not only technically and economically viable but in addition an inevitable tool to make concrete more environmentally friendly. In this context, the use of polysaccharides has increasingly gained interest in the built environment as sustainable resource for performance enhancement. However, due to its origin, biopolymers possess a vast variety of molecular structures which can result in incompatibilities with other polymers present in concrete, such as superplasticizers. The present study highlights effects of the joint application of different types of starches and polycarboxylates with respect to their influence on cement hydration and structural build-up of cement pastes. KW - Polysaccharides KW - Superplasticizers KW - Hydration KW - Cement PY - 2022 DO - https://doi.org/10.4028/www.scientific.net/CTA.1.563 SN - 2674-1237 SP - 563 EP - 568 PB - Trans Tech Publications Ltd, Switzerland CY - Basel, Switzerland. AN - OPUS4-58325 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Mezhov, Alexander A1 - Robens-Radermacher, Annika T1 - Temperature Impact on the Structural Build-Up of Cementitious Materials - Experimental and Modelling Study N2 - With increasing focus on industrialized processing, investigating, understanding, and modelling the structural build-up of cementitious materials becomes more important. The structural build-up governs the key property of fresh printable materials -- buildability -- and it influences the mechanical properties after the deposition. The structural build-up rate can be adjusted by optimization of the mixture composition and the use of concrete admixtures. Additionally, it is known, that the environmental conditions, i.e. humidity and temperature have a significant impact on the kinetic of cement hydration and the resulting hardened properties, such as shrinkage, cracking resistance etc. In this study, small amplitude oscillatory shear (SAOS) tests are applied to examine the structural build-up rate of cement paste subject to different temperatures under controlled humidity. The results indicate significant influences of the ambient temperature on the intensity of the re-flocculation (Rthix) rate, while the structuration rate (Athix) is almost not affected. A bi-linear thixotropy model extended by temperature dependent parameters coupled with a linear viscoelastic material model is proposed to simulate the mechanical behaviour considering the structural build-up during the SAOS test. T2 - Third RILEM International Conference on Concrete and Digital Fabrication (Digital Concrete 2022) CY - Loughborough, UK DA - 27.06.2022 KW - Structural build-up KW - Rheological properties KW - Modelling PY - 2022 AN - OPUS4-55581 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Lorenzoni, Renata T1 - Microstructure of biochar-based concrete: MIP, gas sorption, NMR, and μ-CT analysis N2 - The global demand for concrete is growing, and with it, its carbon footprint. Current literature proposes biochar, a product of pyrolysis, as a possible car-bon sink to reduce the carbon footprint of concrete. This work investigates the microstructure of Portland cement pastes with 0%, 5%, and 25% of the cement replaced with wood biochar, since this should influence its macro-scopic mechanical properties. MIP, gas sorption, NMR, and µ-CT were used to analyze the pore space of the three materials. The combination of these methods, each with different resolution, enables a multi-scale investigation of biochar impact on the microstructure of cement pastes. NMR confirmed that biochar can absorb moisture and, thus, reduces the effective water-to-cement ratio. MIP and gas sorption results show 0% and 5% volume re-placement have similar gel pore structure. The results from µ-CT investiga-tions suggest that biochar may reduce the formation of larger pores. The in-clusion of non-reactive porous particles such as biochar increase the porosity of the material and should act as a weakness in terms of mechanical proper-ties. Overall, this study highlights the need to carefully tailor replacement rates to control the impact of biochar on the microstructure concrete mixtures and sees a strong need for further studies on mechanical properties. T2 - 5th International Conference on Bio-Based Building Materials CY - Vienna, Austria DA - 20.06.2023 KW - Biochar KW - Microstructure KW - Cement KW - Porosity PY - 2023 AN - OPUS4-57948 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Zhang, K. A1 - Mezhov, Alexander A1 - Schmidt, Wolfram T1 - Thixotropic and chemical structural build-up of cement pastes with superplasticizer under different storage conditions N2 - Synopsis: The paper presents the results of a study on the influence of agitation on the structural build-up of fresh cement pastes using a penetration test. It first presents results about the influence of the penetrating shape’s geometry on the influence on the cement paste specimen. Then, results are shown for the load-deflection curves depending upon time and agitation before testing. Based on the observation of the force required to penetrate the sample, conclusions on the structural build-up can be made. The observations were made over the course of time with samples that were left at rest and partly agitated before testing at different time steps. The setup allows to identify the contribution of the chemical reaction to the structural build-up process. The presence of superplasticizer obviously reduces the load that cement paste can withstand, while the loss of thixotropy is found notably lower than that of neat cement pates T2 - 13th International Conference on Superplasticizers and Other Chemical Admixtures in Concrete CY - Milan, Italy DA - 10.07.2022 KW - Thixotropy KW - Superplasticizer KW - Structural build-up KW - Texture analyzer KW - Penetration test PY - 2022 DO - https://doi.org/10.14359/51736058 VL - 354 SP - 13 EP - 24 PB - ACI Special Publications AN - OPUS4-58324 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - de Carvello, J. M. F. A1 - Carvalho Fontes, W. A1 - de Azevedo, C. F. A1 - Brigolini, G. J. A1 - Schmidt, Wolfram A1 - Fiorotti Peixoto, R. A. T1 - Enhancing the eco-efficiency of concrete using engineered recycled mineral admixtures and recycled aggregates N2 - Non-conventional densely packed concrete mixtures are proposed and evaluated in this paper using engineered recycled mineral admixtures and recycled aggregates obtained from steel slag, quartz mining tailings, and quartzite mining tailings. High fines content sand-concretes containing coarser- and finer-than-cement recycled powders were designed to obtain blends with broader particle-size ranges and improved packing density. As a result, compressive strength up to 99 MPa, cement intensity up to 2.33 kg/m³/MPa, and consumption of recycled material up to 95 vol% were obtained. Compressive strengths up to 66 MPa and cement intensity up to 2.34 kg/m³/MPa were also obtained with the addition of coarse aggregates to such sand-concrete mixtures, with consumption of recycled material up to 96.5%. The results launch new insights on the role of recycled admixtures and aggregates on the mixture design of cement-based composites regarding efficiency improvement and technological performance. KW - Low-cement concrete KW - Recycled mineral admixture KW - Basic oxygen furnace slag KW - Quartzite mining tailing KW - Packing density PY - 2020 DO - https://doi.org/10.1016/j.jclepro.2020.120530 VL - 257 SP - 1 EP - 12 PB - Elsevier AN - OPUS4-58401 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Cunningham, Patrick A1 - Schmidt, Wolfram T1 - Cement and clinker imports: embodied carbon, carbon costs, and the EU Carbon Border Adjustment Mechanism (CBAM) N2 - When the European Union (EU) Carbon Border Adjustment Mechanism (CBAM) comes into force, importers of Portland cement and clinker will be required to purchase carbon allowances for their goods. Herein, the trade flows into the EU are mapped by country and the equivalent carbon dioxide (CO2-eq) emissions from production is modeled. Using average allowance prices, the additional cost passed to the consumer if carbon allowances had been purchased for imports in the modeled years are estimated. Together, this retrospective analysis provides insights into CBAM and the potential implications of carbon allowances on the cost of imported goods. KW - Carbon border adjustment mechanism KW - Carbon allowances KW - Cost of carbon KW - Cement KW - Impact shifting PY - 2025 UR - https://www.zkg.de/en/artikel/cement-and-clinker-imports-embodied-carbon-carbon-costs-and-the-eu-carbon-border-adjustment-mechanism-cbam-4252088.html SN - 2748-8330 IS - 3 SP - 54 EP - 58 PB - Bauverlag BV GmbH CY - Gutersloh, Germany AN - OPUS4-63333 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bessaies-Bey, H. A1 - Khayat, K. H. A1 - Palacios, M. A1 - Schmidt, Wolfram A1 - Roussel, N. T1 - Viscosity modifying agents: Key components of advanced cement-based materials with adapted rheology N2 - Viscosity modifying agents (VMAs) are essential ingredients for the production of flowable cement-based materials. This paper presents an overview of commonly used VMAs and attempts to shed some light on the underlying physics at the origin of their mechanisms of action. The main molecular parameters of VMA controlling the rheological properties of the cement pore solution are highlighted. As the mechanisms of action of VMAs in cement-based materials are closely related to their affinity with the surface of cement particles, the adsorption of the main VMA types is discussed. The effect of VMAs on flow properties and stability of cement-based materials is presented for VMAs added without any superplasticizer, and then in systems incorporating both VMAs and superplasticizers. Finally, the effect of VMAs in enhancing concrete properties to secure adequate performance of different construction applications, and perspectives for future developments of novel cement-based materials made with VMAs are showcased. KW - Viscosity modifying agents KW - Cement KW - Stability KW - Rheology KW - Working mechanism KW - Compatibility PY - 2022 DO - https://doi.org/10.1016/j.cemconres.2021.106646 VL - 152 SP - 1 EP - 20 PB - Elsevier AN - OPUS4-58396 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz A1 - Said, Samir T1 - System and damage identification for cars, floors and roofs, bridges, tracks and foundations by modal analyses, frequency response functions and moving-load responses N2 - The following objects have been analysed by frequency response functions and moving load responses. A simple modal analysis which is based on the transformed and weighted system equations has been tested for an automotive test car and for many floors in many buildings to get some rules for their natural frequency and damping. Moreover, six neighboured equal, weakly coupled, wooden floors in a castle have been measured by ambient and hammer excitation, and a special method to extract the different mode shapes of the closely spaced natural frequencies has been developed and tested. Different foundations, for which the soil-structure interaction is generally important, have been measured and compared with finite-element boundary-element models of varying soil properties. Similarly by FEBEM calculations, damages in railway tracks have been identified from flexibility functions (frequency response functions) and from the moving-load responses to normal train operation. Rail and foot bridges have been measured during train passages and by quasi-static tests with moving vehicles. The repeatability of the inclinometer measurements has been checked for different passages, passage directions, and measurement campaigns at a six-span foot bridge. Two rail bridges at the Hanover-Würzburg high-speed line have been measured and evaluated for integrity and for the train- and speed-dependent bridge resonances. The relation between the multi-axle and the single-axle excitation can be solved in frequency domain by the axle-sequence spectrum of the vehicle or the whole train. The single axle response has been used to identify track and bridge damages in laboratory and in situ. T2 - 10th International Operational Modal Analysis Conference (IOMAC 2024) CY - Naples, Italy DA - 21.05.2024 KW - Weakly coupled floors KW - Bridge passage KW - Track damage KW - Foundation-soil interaction KW - Flexibility function KW - Moving load response PY - 2024 SN - 978-3-031-61420-0 DO - https://doi.org/10.1007/978-3-031-61421-7_19 SN - 2366-2557 SP - 187 EP - 195 PB - Springer Nature Switzerland AG CY - Cham, Schweiz AN - OPUS4-61248 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz T1 - Die Minderung von Bahnerschütterungen – Messergebnisse aus Österreich, Deutschland und der Schweiz N2 - Die Minderung von Bahnerschütterungen neben Eisenbahnstrecken ist an vielen Stellen gemessen worden. Dabei ist neben der hochfrequenten Wirkung von elastischen Gleiselementen wie Schienenlager, Schwellensohlen und Unterschottermatten auch oft eine tieffrequente Minderung beobachtet worden. Diese tieffrequente Minderung wird interpretiert und mit der weiteren Lastverteilung der statischen Last erklärt. T2 - Wiener Dynamik Tage CY - Vienna, Austria DA - 25.07.2027 KW - Bahnerschütterungen KW - Minderung KW - Messungen KW - Schwellensohlen KW - Unterschottermatte KW - Gleistrog PY - 2024 AN - OPUS4-61228 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz T1 - Vibraciones de estructuras multi vanos como forjados, puentes ferroviarios y de carreteras N2 - Se han analizado las frecuencias y las formas modales de las estructuras multi-vanos en teoría y mediante ocho ejemplos medidos. Como consecuencia por los puentes de ferrocarril, se han calculado las amplitudes de resonancia en el dominio de las frecuencias con los espectros del tren, de la fuerza modal, y de la resonancia. Para los vanos (idénticos) continuos resp. simplemente apoyados el acoplamiento es fuerte resp. debil, las frecuencias son separadas resp. agrupadas, las formas modales son globales y globales, la resonancia es menor resp. menor – (igual). Los resultados en el dominio del tiempo se obtiene con la transformación inversa de Fourier o – más robusto – el valor de eficaz por la superposición. T2 - DinEst 2024 Third Conference on Structural Dynamics CY - Seville, Spain DA - 12.09.2024 KW - Multi-span bridges KW - Train passage KW - Resonance PY - 2024 AN - OPUS4-61225 LA - spa AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz T1 - The excitation, propagation, and mitigation of train-induced ground vibrations from the axle impulses on the track N2 - Train-induced vibrations in soft ground usually have a strong low-frequency component. This component has a characteristic spectrum which is related to the axle sequence and the speed of the train. Its attenuation with distance is weaker than the attenuation for higher frequencies, and it always dominates the far-field ground vibration. Narrow-band frequency analyses clearly show that this ground vibration component is due to the static axle loads. Axle box vibrations have a different characteristic where the first out-of-roundness of the wheels is the only remarkable low-frequency component. Therefore, the dynamic axle loads from wheel and track irregularities are not the reason for the strong ground vibration component. The moving static axle loads generate the quasi-static response of the soil at very low frequencies and at very near distances. A part of the original impulse spectrum is scattered when it propagates through an inhomogeneous ballast and soil with a randomly varying stiffness. The axle impulses are smoother for a higher bending stiffness or a lower support stiffness (under sleeper pads, under ballast mats) of the track. This mitigation of the ground vibration will be demonstrated by measurements at three sites in Switzerland as well as the characteristic of the soil and axle-box vibrations. T2 - Railways Conference CY - Prague, Czech Republic DA - 02.09.2024 KW - Soil and vehicle measurements KW - Train passages KW - Ground vibration KW - Excitation mechanisms KW - Mitigation KW - Under sleeper pads KW - Under ballast mat PY - 2024 AN - OPUS4-61226 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz A1 - Song, Jiaojiao T1 - Analysis of intact and damaged (floating) slab tracks by finite-element boundary-element models and by measurements N2 - The damage detection and repair control have become important tasks for slab tracks. Different intact and damaged slab tracks have been investigated theoretically and experimentally for train passages and hammer impacts. The following damages have been considered: The loss of contact between the sleeper and the track slab, between the track slab and the base slab, and between the base slab and the base layer. At first, a slab track with a gap between the track slab and the base layer has been calculated by the combined finite-element boundary-element method which correctly incorporates the behaviour of the infinite soil. The basic results are the track displacements of the rail, the track slab, and the base layer along the track which are caused by a single axle load. These solutions are properly superposed for to get the complete train load. The influence of track and soil parameters and of the track damage has been analysed. For the intact track, the compliance of the soil is dominant whereas the track bending stiffness becomes more important for the damaged track. By comparing the calculated results with the measurements, the length of the gap could be quantified. A slab track with a loose sleeper (without contact to the supporting track slab) was analysed by the transfer function between the displacements and the hammer force (receptance functions) where a resonance appeared in case of the damage. Differences between the different track elements confirmed the detection of the damage. A floating slab track with a thin rubber layer has been investigated for a possible gap between the base slab and the base layer. The behaviour of the intact track has been calculated by a wavenumber-domain method, and the same behaviour has been found in the measurements at several track sections, indicating that there is no damage. Finally, a floating slab track with steel springs and viscous fluid dampers has been measured in the Tongji laboratory. The modes of the floating track slab and the transfer function with corresponding resonances have been calculated and successfully compared with results from wheelset drop tests. T2 - 3rd International Conference of Rail Transportation CY - Shanghai, China DA - 07.08.2024 KW - Slab tracks KW - Damage KW - Vibration measurements KW - Finite-element boundary-element method PY - 2024 AN - OPUS4-61227 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz T1 - Vibrations of multi-span structures like floors, rail and road bridges N2 - Resonances of rail bridges due to the passage of trains have been mainly investigated for sin-gle-span bridges. When multi-span bridges are to be considered, it is of interest if stronger resonance amplifications must be taken into account. Measurements of several multi-span structures have been evaluated for natural frequencies and mode shapes. An integral rail bridge with three different spans shows a separated local resonance of the longest main span and clearly higher natural frequencies of the shorter side spans. A two-span continuous beam on the test area of the Federal Institute of Material Research and Testing showed a regular pattern of natural frequencies where always a pair of frequencies is found with a certain fre-quency ratio. The corresponding mode shapes are the out-of-phase and in-phase combinations of the first, second, third … bending mode. A seven-span road bridge has been monitored for one of the almost equally long spans. Similar mode shapes have been observed for different, clearly separated natural frequencies. Three modal analyses measurement campaigns have been performed on the whole bridge. The combined mode shapes of the seven spans have been clearly identified where different combinations of spans are dominating in the different mode shapes. Equal weakly coupled spans have been analysed for a large wooden floor in a castle. A cluster of natural frequencies has been observed and a special method to extract the mode shapes has been developed and tested. The consequences of multi-span bridges for rail traffic will be discussed. If n simply supported bridge spans have no coupling, n equal modes with amplitude A/n exist and their superposition would yield the same resonance as for a single bridge. Real simply supported bridges have always a weak coupling due to the track or the common piers. Therefore, the natural frequencies differ a little and they cannot be in reso-nance at the same time for the same train passage so that the resonance amplification cannot be as strong as for the single bridge. This rule holds also for the average amplitude of the time history of the bridge passage which is an adequate quantity to judge for the bridge behaviour. The maximum amplitude of the time histories of different bridge points are quite random and could exceed the values of a single bridge. The meaning of such criteria is questioned and fre-quency domain analyses are suggested for a clearer bridge analysis and understanding. T2 - DinEst 2024 Third Conference on Structural Dynamics CY - Seville, Spain DA - 12.09.2024 KW - Rail bridge PY - 2024 SP - 41 EP - 59 PB - Escuela Tecnica Superior de Ingenieria CY - Sevilla AN - OPUS4-61238 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz T1 - Die Minderung von Bahnerschütterungen – Messergebnisse aus Österreich, Deutschland und der Schweiz N2 - Die Minderung von Bahnerschütterungen neben Eisenbahnstrecken ist an vielen Stellen gemessen worden. Dabei ist neben der hochfrequenten Wirkung von elastischen Gleiselementen wie Schienenlager, Schwellensohlen und Unterschottermatten auch oft eine tieffrequente Minderung beobachtet worden. Diese tieffrequente Minderung wird interpretiert und mit der weiteren Lastverteilung der statischen Last erklärt. T2 - 3. Wiener Dynamik Tage CY - Vienna, Austria DA - 25.07.2024 KW - Bahnerschütterungen KW - Minderung KW - Messungen KW - Schwellensohlen KW - Unterschottermatten KW - Gleistrog PY - 2024 SP - 1 EP - 13 AN - OPUS4-61244 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz T1 - Prediction of ground vibrations from rail tunnels –finite-element, boundary-element and wavenumber calculations N2 - The prediction of ground and building vibrations has been established for surface lines and has now been extended to tunnel lines. The wave propagation in homogeneous or layered soils (the transmission) is calculated by an integration in wavenumber domain. The wave amplitudes at different distances and for different frequencies will be analysed for the following situations. 1. The horizontal propagation from a surface point to a surface point constitutes the basic rules. 2. The horizontal propagation from a source point at depth to a receiver point at depth which is related to a building with a deep basement or on a pile foundation. 3. The propagation from depth to the surface, which is the normal case for free-field measurements, has some different characteristics, for example a weaker attenuation with the horizontal distance from the source, which can be approximated by the full-space solution and the reflection rules for incident waves. The emission from a tunnel structure has been calculated by a finite-element model of the tunnel combined with a boundary-element model of the soil giving the reduction compared to a point-load excitation. The immission has been analysed by finite-element models of tunnel-soil-building systems for examples of research and consultancy work. Measurement results from a high-speed and a metro line confirm some of the established rules. Figure T2 - Int. Conf. RASD, Recent Advance in Structural Dynamics CY - Southampton, GB DA - 01.07.2024 KW - Ground vibration KW - Tunnel line KW - Wave propagation KW - Wavenumber method KW - Building vibration KW - Thin layer method PY - 2024 SP - 1 EP - 12 CY - Southampton AN - OPUS4-61266 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz A1 - Conreaux, Laurence A1 - Said, Samir A1 - Müller, Roger T1 - The excitation, propagation, and mitigation of train-induced ground vibrations from the axle impulses on the track N2 - Train-induced vibrations in soft ground usually have a strong low-frequency component. This component has a characteristic spectrum which is related to the axle sequence and the speed of the train. Its attenuation with distance is weaker than the attenuation for higher frequencies, and it always dominates the far-field ground vibration. Narrow-band frequency analyses clearly show that this ground vibration component is due to the static axle loads. Axle box vibrations have a different characteristic where the first out-of-roundness of the wheels is the only remarkable low-frequency component. Therefore, the dynamic axle loads from wheel and track irregularities are not the reason for the strong ground vibration component. The moving static axle loads generate the quasi-static response of the soil at very low frequencies and at very near distances. A part of the original impulse spectrum is scattered when it propagates through an inhomogeneous ballast and soil with a randomly varying stiffness. The axle impulses are smoother for a higher bending stiffness or a lower support stiffness (under sleeper pads, under ballast mats) of the track. This mitigation of the ground vibration will be demonstrated by measurements at three sites in Switzerland as well as the characteristic of the soil and axle-box vibrations. T2 - Sixth International Conference on Railway Technology: Research, Development and Maintenance CY - Prague, Czech Republic DA - 01.09.2024 KW - Soil and vehicle measurements KW - Train passages KW - Ground vibration KW - Excitation mechanisms KW - Mitigation KW - Under sleeper pads KW - Under ballast mat PY - 2024 DO - https://doi.org/10.4203/ccc.7.13.2 SN - 2753-3239 VL - 7 SP - 1 EP - 13 PB - Civil-Comp Press CY - Edinburgh, United Kingdom AN - OPUS4-61240 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz T1 - Reduction of ground-induced building vibrations by kinematic and inertial soil-structure interac-tion and by base isolation N2 - Many buildings on the soil have been measured and the transfer function freefield-to-building is ana-lysed. In general, an amplification at low frequencies, an amplification for the floor resonances, and a reduction for higher frequencies can be observed. Most of the measurement examples show a flexible behaviour along the height of the buildings. The prediction of building vibration consists typically of three steps. At first, the dynamic stiffness of the foundation and secondly the kinematic soil-structure interaction has to be calculated for example by the combined finite-element boundary-element meth-od. The stiffness of the foundation reduces the incoming waves (the kinematic interaction). Finally, the inertial interaction of the building with the foundation soil is calculated by the conventional finite ele-ment method where the dynamic foundation stiffness from the first step is added at the bottom of the building. The building on the compliant soil has a fundamental vertical resonance usually below 10 Hz. A parametrical variation clearly shows the influence of the elasticity of the building on this reso-nance frequency and amplitude. Moreover for column-type office buildings, the low-frequency floor resonances can further reduce this fundamental frequency. A 1-dimensional model has been estab-lished which can well approximate the behaviour of the 3-dimensional building models. It is used to demonstrate the effect of a base isolation with soft elements at the foundation. A rigid building model clearly over-estimates the isolation effect, which is smaller for a model with flexible walls, columns and floors. An even simpler model of an infinitely high building is suggested for the mitigation effect, and the resonance frequency of the rigid building should be replaced by a better performance indica-tor, which is based on the impedance ratio of the isolation and the wall and which can be also ex-pressed as a characteristic frequency. T2 - 30th International Congress on Sound and Vibration CY - Amsterdam, Netherlands DA - 08.07.2024 KW - Building vibrations KW - Base isolation KW - Foundation stiffness KW - Kinematic soil-structure interaction KW - Transfer functions of flexible buildings PY - 2024 SN - 978-90-90-39058-1 SN - 2329-3675 SP - 1 EP - 8 AN - OPUS4-61245 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz T1 - System and damage identification for cars, floors and roofs, bridges, tracks and foundations by modal analyses, frequency response functions and moving load responses N2 - The following objects have been analysed by frequency response functions and moving load responses. A simple modal analysis which is based on the transformed and weighted system equations has been tested for an automotive test car and for many floors in many buildings to get some rules for their natural frequency and damping. Moreover, six neighboured equal, weakly coupled, wooden floors in a castle have been measured by ambient and hammer excitation, and a special method to extract the different mode shapes of the closely spaced natural frequencies has been developed and tested. Different foundations, for which the soil-structure interaction is generally important, have been measured and compared with finite-element boundary-element models of varying soil properties. Similarly by FEBEM calculations, damages in railway tracks have been identified from flexibility functions (frequency response functions) and from the moving-load responses to normal train operation. Rail and foot bridges have been measured during train passages and by quasi-static tests with moving vehicles. The repeatability of the inclinometer measurements has been checked for different passages, passage directions, and measurement campaigns at a six-span foot bridge. Two rail bridges at the Hanover-Würzburg high-speed line have been measured and evaluated for integrity and for the train- and speed-dependent bridge resonances. The relation between the multi-axle and the single-axle excitation can be solved in frequency domain by the axle-sequence spectrum of the vehicle or the whole train. The single axle response has been used to identify track and bridge damages in laboratory and in situ. T2 - 10th International Operational Modal Analysis Conference (IOMAC 2024) CY - Naples, Italy DA - 21.05.2024 KW - Weakly coupled floors KW - Bridge passage KW - Track damage KW - Foundation-soil interaction KW - Flexibility function KW - Moving load response PY - 2024 AN - OPUS4-61233 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz T1 - Railway vibration fast physics based models for the prediction of ground vibration and the identification of track damage N2 - The following applications of machine learning will be discussed: 1. The prediction of the wave propagation from a railway line (completely physics based for surface lines, physics-based machine learning for tunnel lines) 2. The track behaviour for the emission of train-induced ground vibration (physics based for homogeneous soil, machine learning for layered soil) 3. Track damage detection and quantification from frequency response functions and moving load responses 4. Bridge damage detection and localisation from modal analysis and moving load 5. The use of axle-box acceleration for the identification of track/sub-soil condition and bridge resonances. The prediction of railway vibration usually needs time-consuming finite element, boundary element and wavenumber domain calculations. For a user-friendly prediction software however, fast calculations are needed. Several time-consuming detailed calculations have been used to develop simpler and fast models for the surface railway lines. The more challenging prediction from tunnel lines will be attacked by purely mathematical and by physics-informed machine learning. The dynamic stiffnesses of isolated or un-isolated railway tracks from detailed calculations with a continuous soil have been approximated with the simpler Winkler soil. The vehicle-track resonance (P2 resonance) rules the effect of the mitigation measures, and it can also be used for the on-board monitoring of the track and sub-soil condition. For the identification of track damage such as gaps between sleepers, track slabs and layers, detailed models with a continuous soil have been updated to get the best fit to the measured frequency response functions from hammer tests and the deformation pattern from the moving load response. Whereas the track damage can be locally identified, this is more difficult for bridges where the modal analysis gives mainly global information. The influence lines of the inclination for statically passing vehicles (locomotive, truck, compaction roller) have been used to localise bridge damage (stiffness variations). The on-board monitoring of rail bridges needs special conditions (regular trains with special speeds) to excite and measure the bridge resonance. T2 - 11th European Workshop on Structural Health Monitoring (EWSHM) CY - Potsdam, Germany DA - 10.06.2024 KW - Vibration prediction KW - Track damage detection KW - Human and machine learning KW - Wave propagation KW - Surface line KW - Tunnel KW - Bridge resonance PY - 2024 AN - OPUS4-61231 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz T1 - Reduction of ground induced building vibrations by kinematic and inertial soil structure interaction and by base isolation N2 - Many buildings on the soil have been measured and the transfer function freefield-to-building is ana-lysed. In general, an amplification at low frequencies, an amplification for the floor resonances, and a reduction for higher frequencies can be observed. Most of the measurement examples show a flexible behaviour along the height of the buildings. The prediction of building vibration consists typically of three steps. At first, the dynamic stiffness of the foundation and secondly the kinematic soil-structure interaction has to be calculated for example by the combined finite-element boundary-element meth-od. The stiffness of the foundation reduces the incoming waves (the kinematic interaction). Finally, the inertial interaction of the building with the foundation soil is calculated by the conventional finite ele-ment method where the dynamic foundation stiffness from the first step is added at the bottom of the building. The building on the compliant soil has a fundamental vertical resonance usually below 10 Hz. A parametrical variation clearly shows the influence of the elasticity of the building on this reso-nance frequency and amplitude. Moreover for column-type office buildings, the low-frequency floor resonances can further reduce this fundamental frequency. A 1-dimensional model has been estab-lished which can well approximate the behaviour of the 3-dimensional building models. It is used to demonstrate the effect of a base isolation with soft elements at the foundation. A rigid building model clearly over-estimates the isolation effect, which is smaller for a model with flexible walls, columns and floors. An even simpler model of an infinitely high building is suggested for the mitigation effect, and the resonance frequency of the rigid building should be replaced by a better performance indica-tor, which is based on the impedance ratio of the isolation and the wall and which can be also ex-pressed as a characteristic frequency. T2 - 30th International Congress on Sound and Vibration CY - Amsterdam, Netherlands DA - 08.07.2024 KW - Building vibrations KW - Base isolation KW - Foundation stiffness KW - Kinematic soil-structure interaction KW - Transfer functions of flexible buildings PY - 2024 AN - OPUS4-61229 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz A1 - Song, Jiaojiao T1 - Analysis of intact and damaged (floating) slab tracks by finite-element boundary-element models and by measurements N2 - The damage detection and repair control have become important tasks for slab tracks. Different intact and damaged slab tracks have been investigated theoretically and experimentally for train passages and hammer impacts. The following damages have been considered: The loss of contact between the sleeper and the track slab, between the track slab and the base slab, and between the base slab and the base layer. At first, a slab track with a gap between the track slab and the base layer has been calculated by the combined finite-element boundary-element method which correctly incorporates the behaviour of the infinite soil. The basic results are the track displacements of the rail, the track slab, and the base layer along the track which are caused by a single axle load. These solutions are properly superposed for to get the complete train load. The influence of track and soil parameters and of the track damage has been analysed. For the intact track, the compliance of the soil is dominant whereas the track bending stiffness becomes more important for the damaged track. By comparing the calculated results with the measurements, the length of the gap could be quantified. A slab track with a loose sleeper (without contact to the supporting track slab) was analysed by the transfer function between the displacements and the hammer force (receptance functions) where a resonance appeared in case of the damage. Differences between the different track elements confirmed the detection of the damage. A floating slab track with a thin rubber layer has been investigated for a possible gap between the base slab and the base layer. The behaviour of the intact track has been calculated by a wavenumber-domain method, and the same behaviour has been found in the measurements at several track sections, indicating that there is no damage. Finally, a floating slab track with steel springs and viscous fluid dampers has been measured in the Tongji laboratory. The modes of the floating track slab and the transfer function with corresponding resonances have been calculated and successfully compared with results from wheelset drop tests. T2 - Third International Conference on Rail Transportation (ICRT2024) CY - Shanghai, China DA - 07.08.2024 KW - Railway track KW - Damage KW - Vibration measurement KW - Finite element method KW - Boundary element method KW - Frequency response function KW - Moving load response KW - Floating slab track PY - 2024 SP - 1 EP - 10 AN - OPUS4-61267 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Auersch, Lutz T1 - Vehicle Dynamics and Train‑Induced Ground Vibration—Theoretical Analyses and Simultaneous Vehicle, Track, and Soil Measurements N2 - Ground vibrations near railway lines are generated by the forces that are acting between wheel and rail. It seems to be a straight forward assumption that the vehicle dynamics are important for the level and the frequencies of the excitation forces. Different vehicle dynamics phenomena are analysed for their role in the excitation of ground vibrations: rigid body modes of the bogies, elastic (bending) modes of the car body, and elastic modes of the wheelset. The theoretical analyses use rigid body models, simplified elastic models, and detailed elastic models. Some of these problems are vehicle–track interaction problems where 3D finite‑element boundary‑element models have been used for the track and soil. It is shown that the rigid or flexible vehicle modes are well in the frequency range of ground vibrations (4 to 100 Hz). They have an influence on the excitation force but the additional forces are rather small and can be neglected in ground vibration prediction. The theoretical results are checked by experimental results of a simultaneous measurement of vehicle, track, and ground vibrations. KW - Rigid vehicle model KW - Flexible car body KW - Flexible wheelset KW - Dynamic loads KW - Ground vibration PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-569796 DO - https://doi.org/10.3390/vehicles5010013 VL - 5 IS - 1 SP - 223 EP - 247 PB - MDPI CY - Basel AN - OPUS4-56979 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Agasty, Amit T1 - A Preliminary Study on the Scaling of RC Structures under Blasting Loading N2 - Current capabilities for full-scale field blast testing are highly resource intensive. Reliable small-scale experiments are an effective alternative. Characterization of the dynamic response and damage of RC elements to scaled blast loads was investigated in scaled-down field experiments. Spatially resolved information on the dynamic structural response to blast loading was obtained using distributed fiber optic acoustic sensing (DAS), acceleration sensors as well as piezoelectric pressure sensors. T2 - 46. Informationstagung Sprengtechnik CY - Siegen, Germany DA - 25.04.2025 KW - Explosives KW - Blast and scaling effects KW - Concrete PY - 2025 AN - OPUS4-62994 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Costard, René T1 - Charakterisierung der Belastung und Schädigung von Stahlbetonprüfkörpern unter Explosionsbeanspruchung N2 - Sprengversuche sind ein wesentliches Werkzeug, um die Eignung von Schutzobjekten und Bauteilen zum Schutz der Bevölkerung vor Anschlägen mit explosionsgefährlichen Stoffen wie Explosivstoffen, sogenannten „home-made-explosives“ (HME) und unkonventionellen Spreng- und Brandvorrichtungen (USBV) zu bewerten. Für forensische Zwecke werden oft Explosionsszenarien nachgebildet, um die Auswirkung von Anschlägen oder Unfällen genau untersuchen zu können. Feldversuche in Kombination mit numerischen Simulationen ermöglichen eine Charakterisierung der Belastung und Schädigung von Bauteilen und Strukturen unter hochdynamischen Explosionsbelastungen. Auf dem Testgelände Technische Sicherheit (TTS) der BAM in Horstwalde, Brandenburg werden Sprengversuche im Real-Maßstab durchgeführt. Dabei werden Bauteile mit Messtechnik ausgestattet, um eine dynamische Strukturcharakterisierung mittels sensorbasierten Monitorings zu ermöglichen. In diesem Vortrag werden am Beispiel einer Versuchskampagne mit einer Stahlbetonwand als Prüfkörper die Eignung verschiedener Prüfmethoden bei Sprengversuchen evaluiert. Es werden Messmethoden zur Charakterisierung der Explosionsereignisse, des globalen Strukturverhaltens sowie der lokalen Schädigung vorgestellt. Die direkte Charakterisierung der Explosionsbelastung erfolgt mit Hilfe von piezo-elektrischen Druckaufnehmern (bündig mit der Oberfläche im Prüfkörper montiert) und High-Speed-Kameras. Die Beobachtung der explosionsinduzierten Reaktion des Bauteils während und nach dem Eintreffen der Stoßwelle erfolgt mittels Beschleunigungssensoren, Stereo-Fotogrammetrie sowie mit in den Prüfkörper eingebetteter verteilter faseroptischer Sensoren, mit Hilfe derer die Dehnungsraten im Bauteil zeit- und ortsaufgelöst gemessen werden können. Die faseroptischen Sensoren erlauben außerdem die örtlich hochaufgelöste Bestimmung statischer Dehnungsänderungen im Bauteil nach einem Versuch, sodass auch nicht sichtbare Schädigungen wie kleinste Risse detektiert und charakterisiert werden können. Vergleichende Messungen mit Ultraschall komplettieren die Schadenscharakterisierung. In unserem Beitrag diskutieren wir die Herausforderungen dieser Messungen sowie die Ergebnisse und Möglichkeiten der genannten komplementären Messmethoden. T2 - 44. Informationstagung Sprengtechnik CY - Siegen, Germany DA - 14.04.2023 KW - Explosivstoffe KW - Sprengversuche KW - Schädigungscharakterisierung KW - Sensorik PY - 2023 AN - OPUS4-57319 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Agasty, Amit T1 - Numerical analysis of structures under blast loading N2 - Blast tests are indispensable for investigations of accidental or intentional explosions and to evaluate the level of protection to people and equipment within critical infrastructure. Current capabilities for detailed blast effects assessment are limited to performing full-scale field testing, which, for complex scenarios, are highly resource intensive. In this regard, reliable numerical simulations are an effective alternative option. A discussion of the scope and challenges of using numerical tools for a technical-safety assessment of reinforced concrete structures under blast loading is presented. Different coupling possibilities between shock wave simulations and structural simulations with the help of practical examples is given. An outlook on the development of new methods for structural simulations currently being researched at BAM concludes the presentation. T2 - Exerter Final Conference, 2023 CY - Soest, The Netherlands DA - 24.04.2023 KW - Coupling KW - Numerical Simulation KW - Blast KW - Structural Analysis KW - FSI PY - 2023 AN - OPUS4-57458 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz T1 - Frequenz- und bodenabhängige Prognose und Minderung von Bahnerschütterungen N2 - Die Prognose und Minderung von Bahnerschütterungen haben eine lange Tradition in der Bundesanstalt für Materialforschung und -prüfung. Im Jahr 2006 wurde eine Prognose-Software fertiggestellt, die viele Forschungs- und Messergebnisse zusammenfasst. Sie umfasst die Teilbereiche Emission (die Anregung durch die Fahrzeug-Fahrweg-Untergrund-Wechselwirkung), die Transmission (die Ausbreitung durch den Boden) und die Immission (die Übertragung vom Freifeld in ein Gebäude). Die Prognose geschieht in allen Teilen mit einfachen Formeln, die veröffentlicht sind und zur Anwendung für Jedermann zur Verfügung stehen. Es werden Beispiele zur Emission und zur Transmission gezeigt. Im Bereich Transmissionsprognose werden zu den Anregungskräften (aus dem Emissionsteil) die Bodenerschütterungen als Schwinggeschwindigkeitsterzspektren berechnet. Das Ergebnis hängt stark von der Bodensteifigkeit, -dämpfung und -schichtung ab. Dies wurde später mit einer Messkampagne in der Schweiz an 10 Messorten bestätigt. Die Berechnung erfolgt näherungsweise für einen geschichteten Boden mit einer frequenzabhängigen Wellengeschwindigkeit (Dispersion) oder einem tiefenabhängigen Wellengeschwindigkeitsprofil. Die Anregungskräfte werden im Prognosebereich Emission mit einem 2-dimensionalen Gleismodell berechnet. 1-dimensionale Modelle liefern meist falsche Ergebnisse und 3-dimensionale Modelle (zum Beispiel mit der kombinierten Finite-Element-Randelement-Methode) sind für eine Erschütterungs¬prognose sicherlich zu aufwändig. Das 2-dimensionale Modell wurde an 3-dimensionale Ergebnisse so angepasst, dass die Ergebnisse für viele Gleise und Böden annähernd zutreffen. Auch Minderungs¬maßnahmen am Gleis können mit diesem Modell sehr gut berechnet werden. Die Prognoseverfahren wurden in den folgenden Jahren weiter verfeinert. Es wurde die quasi-statische Anregung durch die bewegten statischen Zuglasten mit einer Näherungsformel ergänzt, so dass auch das tieffrequente Nahfeld realistisch erfasst werden kann. Mit der Berücksichtigung der Achsfolge (insbesondere zwischen den Achsen im Drehgestell) ergeben sich zwei typische Minima in den Erschütterungsspektren, die oft auch in den Messungen beobachtet werden. Der Amplitudenanteil zwischen diesen beiden Minima ist oft stärker angehoben, so dass hier eine zusätzliche Erschütterungsanregung vermutet wird. Dieser Anteil kann rein empirisch prognostiziert werden, so wie das in den englischen Prognosen (zuletzt für das Highspeed2-Projekt) enthalten ist. Die Begründung dieses Anteils ist allerdings nicht die Achsfolge, sondern die Zerstreuung der statischen Achslastimpulse durch einen unregelmäßigen Gleisuntergrund und Boden. Die messtechnische Ermittlung eines Minderungseffektes ist komplizierter als allgemein angenommen. Es reicht nicht aus, jeweils an einem Messpunkt in der Nähe eines Gleises mit und ohne Minderungsmaßnahme die Erschütterungen zu messen und aus dem Verhältnis der Amplituden (beziehungsweise aus der Differenz der Pegel) „die Einfügedämmung“ zu ermitteln. Es wird an Beispielen gezeigt, wie man hier sinnvoller vorgehen kann. 1. Zunächst ist es wichtig, nicht nur die Einfügedämmung sondern auch die Originalspektren mit und ohne Minderung zu dokumentieren und zu veröffentlichen, damit man kontrollieren kann, ob wesentliche Amplituden und Frequenzbereiche reduziert sind oder ob es sich um eher zufällige Minderungen oder Verstärkungen handelt. (Beispiel Unterschottermatte/Raron, Müller/SBB) 2. Der Messpunkt sollte nicht im Nahbereich des Gleises liegen, da ansonsten eine zu günstige, falsche Einfügedämmung bestimmt wird. (Beispiel Tunnel/ Leipzig/Breitsamter) 3. Um Zufälligkeiten zu vermeiden, sollte man an mehr als einem Punkt messen. (Beispiel Unterschotterplatte/Altheim/Auersch) 4. Man sollte eigentlich immer auch die Bodenkennwerte (Steifigkeit, Dämpfung, Amplituden-abnahme, Übertagungsfunktion) messen. Selbst bei nahegelegene Messquerschnitten kann man Überraschungen erleben. (Beispiel erste ICE-Messungen/bei Würzburg/Auersch) 5. Bei verschiedenen Bodenkennwerten kann man eine Korrektur durchführen. (Beispiel Gleis-tröge/Mistler) Am besten bestimmt man ein äquivalentes Kraftspektrum zu jedem Messort und jedem Messzug (Beispiel Feste Fahrbahn/Gardelegen/Auersch) 6. Prinzipiell gibt es nicht die Einfügedämmung einer Maßnahme. Die Einfügedämmung ist immer boden- und referenzsystemabhängig. Die „beste“ Einfügungsdämmung erhält man mit einem steifen Untergrund (Beispiel Unterschottermatte/Tunnel/München Gasteig/Wettschureck) Das heißt aber nicht, dass die Maßnahme durch einen künstlich versteiften Untergrund besser wird (Beispiel Unterschottermatten/RRT2006/Auersch) Es werden Messbeispiele gezeigt, die alle neben einer hochfrequenten dynamischen Minderung auch eine mittelfrequente quasi-statische Minderung aufweisen. Dabei wird der mittelfrequente Zerstreuanteil der statischen Achslastimpulse durch die breitere Lastverteilung und damit die Impulsdehnung der Achslastimpulse reduziert. Diese Impulsdehnung lässt sich mit dem 2-dimensionalen Gleismodell berechnen. Die Minderungswirkung hängt aber wiederum vom Referenzsystem und dessen unregelmäßiger Steifigkeitsverteilung ab. Je unregelmäßiger der Boden und Gleisuntergrund des Referenzsystems, desto stärker ist die Minderungswirkung. T2 - 24. Symposium für Baudynamik und Erschütterungsmessungen CY - Dübendorf, Sitzerland DA - 09.06.2023 KW - Bahnerschütterungen KW - Erschütterungsprognose KW - Erschütterungsminderung KW - Elastische Gleiselemente KW - Gleiströge KW - Zerstreute Achsimpulse PY - 2023 SP - 1 EP - 32 PB - Ziegler Consultants CY - Zürich AN - OPUS4-57953 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz T1 - Frequenz- und bodenabhängige Prognose und Minderung von Bahnerschütterungen N2 - Die Prognose und Minderung von Bahnerschütterungen haben eine lange Tradition in der Bundesanstalt für Materialforschung und -prüfung. Im Jahr 2006 wurde eine Prognose-Software fertiggestellt, die viele Forschungs- und Messergebnisse zusammenfasst. Sie umfasst die Teilbereiche Emission (die Anregung durch die Fahrzeug-Fahrweg-Untergrund-Wechselwirkung), die Transmission (die Ausbreitung durch den Boden) und die Immission (die Übertragung vom Freifeld in ein Gebäude). Die Prognose geschieht in allen Teilen mit einfachen Formeln, die veröffentlicht sind und zur Anwendung für Jedermann zur Verfügung stehen. Es werden Beispiele zur Emission und zur Transmission gezeigt. Im Bereich Transmissionsprognose werden zu den Anregungskräften (aus dem Emissionsteil) die Bodenerschütterungen als Schwinggeschwindigkeitsterzspektren berechnet. Das Ergebnis hängt stark von der Bodensteifigkeit, -dämpfung und -schichtung ab. Dies wurde später mit einer Messkampagne in der Schweiz an 10 Messorten bestätigt (Bild 1). Die Berechnung erfolgt näherungsweise für einen geschichteten Boden mit einer frequenzabhängigen Wellengeschwindigkeit (Dispersion) oder einem tiefenabhängigen Wellengeschwindigkeitsprofil. Die Anregungskräfte werden im Prognosebereich Emission mit einem 2-dimensionalen Gleismodell berechnet (Bild 2). 1-dimensionale Modelle liefern meist falsche Ergebnisse und 3-dimensionale Modelle (zum Beispiel mit der kombinierten Finite-Element-Randelement-Methode) sind für eine Erschütterungs¬prognose sicherlich zu aufwändig. Das 2-dimensionale Modell wurde an 3-dimensionale Ergebnisse so angepasst, dass die Ergebnisse für viele Gleise und Böden annähernd zutreffen. Auch Minderungs¬maßnahmen am Gleis können mit diesem Modell sehr gut berechnet werden. Die Prognoseverfahren wurden in den folgenden Jahren weiter verfeinert. Es wurde die quasi-statische Anregung durch die bewegten statischen Zuglasten mit einer Näherungsformel ergänzt, so dass auch das tieffrequente Nahfeld realistisch erfasst werden kann. Mit der Berücksichtigung der Achsfolge (insbesondere zwischen den Achsen im Drehgestell) ergeben sich zwei typische Minima in den Erschütterungsspektren, die oft auch in den Messungen beobachtet werden. Der Amplitudenanteil zwischen diesen beiden Minima ist oft stärker angehoben, so dass hier eine zusätzliche Erschütterungsanregung vermutet wird. Dieser Anteil kann rein empirisch prognostiziert werden, so wie das in den englischen Prognosen (zuletzt für das Highspeed2-Projekt) enthalten ist. Die Begründung dieses Anteils ist allerdings nicht die Achsfolge, sondern die Zerstreuung der statischen Achslastimpulse durch einen unregelmäßigen Gleisuntergrund und Boden. Die messtechnische Ermittlung eines Minderungseffektes ist komplizierter als allgemein angenommen. Es reicht nicht aus, jeweils an einem Messpunkt in der Nähe eines Gleises mit und ohne Minderungs¬maßnahme die Erschütterungen zu messen und aus dem Verhältnis der Amplituden (beziehungsweise aus der Differenz der Pegel) „die Einfügedämmung“ zu ermitteln. Es wird an Beispielen gezeigt, wie man hier sinnvoller vorgehen kann. 1. Zunächst ist es wichtig, nicht nur die Einfügedämmung sondern auch die Originalspektren mit und ohne Minderung zu dokumentieren und zu veröffentlichen, damit man kontrollieren kann, ob wesentliche Amplituden und Frequenzbereiche reduziert sind oder ob es sich um eher zufällige Minderungen oder Verstärkungen handelt. (Beispiel Unterschottermatte/Raron, Müller/SBB) 2. Der Messpunkt sollte nicht im Nahbereich des Gleises liegen, da ansonsten eine zu günstige, falsche Einfügedämmung bestimmt wird. (Beispiel Tunnel/ Leipzig/Breitsamter) 3. Um Zufälligkeiten zu vermeiden, sollte man an mehr als einem Punkt messen. (Beispiel Unterschotterplatte/Altheim/Auersch) 4. Man sollte eigentlich immer auch die Bodenkennwerte (Steifigkeit, Dämpfung, Amplituden-abnahme, Übertagungsfunktion) messen. Selbst bei nahegelegene Messquerschnitten kann man Überraschungen erleben. (Beispiel erste ICE-Messungen/bei Würzburg/Auersch) 5. Bei verschiedenen Bodenkennwerten kann man eine Korrektur durchführen. (Beispiel Gleis-tröge/Mistler) Am besten bestimmt man ein äquivalentes Kraftspektrum zu jedem Messort und jedem Messzug (Beispiel Feste Fahrbahn/Gardelegen/Auersch) 6. Prinzipiell gibt es nicht die Einfügedämmung einer Maßnahme. Die Einfügedämmung ist immer boden- und referenzsystemabhängig. Die „beste“ Einfügungsdämmung erhält man mit einem steifen Untergrund (Beispiel Unterschottermatte/Tunnel/München Gasteig/Wettschureck) Das heißt aber nicht, dass die Maßnahme durch einen künstlich versteiften Untergrund besser wird (Beispiel Unterschottermatten/RRT2006/Auersch) Es werden Messbeispiele gezeigt, die alle neben einer hochfrequenten dynamischen Minderung auch eine mittelfrequente quasi-statische Minderung aufweisen. Dabei wird der mittelfrequente Zerstreuanteil der statischen Achslastimpulse durch die breitere Lastverteilung und damit die Impulsdehnung der Achslastimpulse reduziert. Diese Impulsdehnung lässt sich mit dem 2-dimensionalen Gleismodell berechnen. Die Minderungswirkung hängt aber wiederum vom Referenzsystem und dessen unregel¬mäßiger Steifigkeitsverteilung ab. Je unregelmäßiger der Boden und Gleisuntergrund des Referenz¬systems, desto stärker ist die Minderungswirkung. T2 - 24. Symposium für Baudynamik und Erschütterungsmessungen CY - Dübendorf, Switzerland DA - 09.06.2023 KW - Bahnerschütterungen KW - Erschütterungsprognose KW - Erschütterungsminderung KW - Elastische Gleiselemente KW - Gleiströge KW - zerstreute Achslastimpulse PY - 2023 AN - OPUS4-57952 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz T1 - Some resonance effects of non-typical trains and railway bridges investigated by a frequency-domain method N2 - The resonances of railway bridges have often been analysed for short bridges under periodical high-speed trains, for simply supported one-span bridges, for the fundamental bridge mode, and by time-domain analyses. Many time-consuming calculations have been performed to establish simplified rules for standards. In this contribution, the passage of different (existing, new and hypothetic) trains over different bridges will be analysed in frequency domain by using three separated spectra with the purpose to get a better physical insight in the phenomena. At first, the excitation spectrum of the modal forces is built by the mode shape and the passage time of the train over the bridge. The second spectrum is the frequency response function of the bridge which include the modal frequency, damping and mass. The third part is the spectrum of the axle sequence of an arbitrary train which is not limited to periodical or specific (conventional, articulated, regular or standard) trains and which does not include any bridge parameters. The final solution in frequency domain is obtained as the product of these three complex, strongly varying spectra for the dominating bridge mode or in general as the sum of these products over all relevant bridge modes. The time domain solution is obtained via the inverse Fourier transform, and the resulting time histories have been successfully compared with some measurement results. The method is applied to the vertical and torsional modes of a mid-long 1-span bridge on elastomeric bearings under standard train speeds, and to a long multi-span integral bridge under long periodical freight trains. Different resonance and cancellation effects have been found for systematically varied train speeds according to the axle sequence of the whole train which is dominated by the two locomotives in that case. To be more specific, the first torsional mode of the mid-span bridge is excited for a train speed of 100 km/h whereas the second bending mode is excited for a train speed of 160 km/h. In both cases, the other mode is suppressed by the minima of the axle-distance spectra. In addition, the case of the German high-speed train ICE4 and the very high-speed hyperloop case will be discussed briefly. In general, it is shown that resonance effects are also worth to be studied for freight and passenger trains with lower speeds. T2 - EURODYN 2023 XII International Conference on Structural Dynamics CY - Delft, Netherlands DA - 03.07.2023 KW - Railway bridge KW - Transfer fuction KW - Modal load spectrum KW - Axle-sequence spectrum KW - Freight train KW - Passenger train KW - High-speed train KW - 2-span bridge PY - 2023 AN - OPUS4-57955 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz T1 - Soil-foundation-structure problems related to train induced vibrations - the kinematic interaction of tunnel excited pile foundations and the inertial interaction of high rise buildings N2 - The soil-foundation-structure interaction is always important when building vibrations due to train passages have to be considered. The frequency range for train vibrations is up to 100 Hz. Normally, soft surface soils are crucial so that the wavelength can be much smaller than the foundation dimensions. Three topics are of interest for the prediction and the under-standing of building vibrations. 1. The „kinematic interaction“ or the „added foundation ef-fect“, which is calculated either by the combined boundary-element finite-element method or by the wavenumber domain method, results in a reduction of the free-field vibration. The stiff-ness of the foundation resists the wave deformation, plates and walls for horizontally propa-gating waves or piles for vertically incident waves. 2. The „inertial interaction“ or the „added building effect“ yields an amplification around the vertical building resonance, which may be a rigid mode on the compliant soil or a flexible mode for high-rise buildings, and a reduction at higher frequencies. This has been analysed by detailed finite element models of apartment and office buildings. 3. Base isolation is a method to further reduce building vibrations. It is important to know the soil-foundation impedance for the possible reduction, as well as the correct building impedance. A high-rise building cannot be considered as a rigid mass model. It has a frequency-dependent behaviour with longitudinal waves travelling from the founda-tion to the top of the building which include the effect of floor vibrations. Experiences from building projects in Vienna, Frankfort and Berlin will give some additional results for the ex-citation from tunnel lines, the kinematic response of pile foundations, and the inertial re-sponse of the flexible multi-storey buildings. T2 - Computational Methods in Structural Dynamics and Earthquake Engineering (COMPDYN 2023) CY - Athens, Greece DA - 12.06.2023 KW - Soil-pile interaction KW - Pile groups KW - Kinematic interaction KW - Inertial interaction KW - High-rise buildings KW - Base isolation PY - 2023 AN - OPUS4-57954 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz T1 - Damage detection by flexibility functions and quasi-static moving load tests N2 - The contribution shows measurement examples of cars, floors, foundations, railway tracks, a footbridge, and a railbridge. Vibrations may include modes and waves. Namely in soil-structure interaction, modes are damped, shifted and prevented so that alternatives for the modal analysis are necessary: The approximation of the whole spectrum (flexibility function) and of the whole train passage (moving-load response). T2 - Symposium Emerging Trends in Bridge Damage Detection, Localization and Quantification CY - Luxembourg, Luxembourg DA - 05.05.2023 KW - Flexibility KW - Movin load test KW - Frequency response function KW - Cars KW - Floors KW - Foundations KW - Railway tracks KW - Footbridge KW - Railbridge KW - Damage detection PY - 2023 AN - OPUS4-57951 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz T1 - Train-induced ground vibrations – The emission and transmission from tunnel and surface lines N2 - Train-induced ground vibrations are quite different for tunnel and surface lines. The excitation of the track and ground vibration by the vehicle-track-soil interaction maybe influenced by the stiffer track support of the tunnel invert. The excited waves are propagating on a different path compared to the surface line. The wave propagation in the interior of the soil is calculated by a wavenumber integral in a similar way as the propagation along the surface and a general reduction of < 0.5 has been found. An additional reduction has been found because of the missing Rayleigh wave. The different excitation of tunnel lines is analysed theoretically by the combined finite-element boundary-element method and some results about the influencing tunnel and soil parameters will be shown. Measurements have been made at the Mühlberg-Tunnel in Germany. The vibrations of the train, the track and the soil have been measured simultaneously at the tunnel and a nearby surface line. Spectra will be shown for different train speeds between 60 and 160 km/h. A clear reduction effect for the tunnel line compared to the surface line has been observed in a specific (train-speed-dependent) frequency range. This agrees well with the observations of other research institutes. The mid-frequency tunnel-surface reduction seems to be a consequence of the stiffer track structure which leads to a wider distribution of the axle loads. Therefore, the axle impulses due to the train passage are longer and have a lower frequency content. This will have an effect on the ground vibrations at some distance which are present in case of an irregular transmission path through a ballast and soil with varying stiffness. A similar reduction effect can also be found for other track forms where the axle impulses are distributed on a longer track segment, for example slab tracks, tracks with under ballast plates, under ballast mats or under sleeper pads. T2 - 29th International Congress on Sound and Vibration (ICSV29) CY - Prague, Czech Republic DA - 09.07.2023 KW - Ground vibration KW - Railway tunnel KW - Layered soil KW - Surface-tunnel reduction KW - Measurements PY - 2023 AN - OPUS4-57956 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz T1 - Soil-foundation-structure problems related to train induced vibrations - the kinematic interaction of tunnel excited pile foundations and the inertial interaction of high rise buildings N2 - The soil-foundation-structure interaction is always important when building vibrations due to train passages have to be considered. The frequency range for train vibrations is up to 100 Hz. Normally, soft surface soils are crucial so that the wavelength can be much smaller than the foundation dimensions. Three topics are of interest for the prediction and the under-standing of building vibrations. 1. The „kinematic interaction“ or the „added foundation ef-fect“, which is calculated either by the combined boundary-element finite-element method or by the wavenumber domain method, results in a reduction of the free-field vibration. The stiff-ness of the foundation resists the wave deformation, plates and walls for horizontally propa-gating waves or piles for vertically incident waves. 2. The „inertial interaction“ or the „added building effect“ yields an amplification around the vertical building resonance, which may be a rigid mode on the compliant soil or a flexible mode for high-rise buildings, and a reduction at higher frequencies. This has been analysed by detailed finite element models of apartment and office buildings. 3. Base isolation is a method to further reduce building vibrations. It is important to know the soil-foundation impedance for the possible reduction, as well as the correct building impedance. A high-rise building cannot be considered as a rigid mass model. It has a frequency-dependent behaviour with longitudinal waves travelling from the founda-tion to the top of the building which include the effect of floor vibrations. Experiences from building projects in Vienna, Frankfort and Berlin will give some additional results for the ex-citation from tunnel lines, the kinematic response of pile foundations, and the inertial re-sponse of the flexible multi-storey buildings. T2 - COMPDYN 2023 CY - Athen, Greece DA - 12.06.2023 KW - Kinematic Interaction KW - Inertial Interaction KW - Surface Foundation KW - Pile Foundation KW - High-Rise Building PY - 2023 SP - 1 EP - 14 PB - NTUA CY - Athens AN - OPUS4-57959 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz T1 - Some resonance effects of non-typical trains and railway bridges investigated by a frequency-domain method N2 - The resonances of railway bridges have often been analysed for short bridges under periodical high-speed trains, for simply supported one-span bridges, for the fundamental bridge mode, and by time-domain analyses. Many time-consuming calculations have been performed to establish simplified rules for standards. In this contribution, the passage of different (existing, new and hypothetic) trains over different bridges will be analysed in frequency domain by using three separated spectra with the purpose to get a better physical insight in the phenomena. At first, the excitation spectrum of the modal forces is built by the mode shape and the passage time of the train over the bridge. The second spectrum is the frequency response function of the bridge which include the modal frequency, damping and mass. The third part is the spectrum of the axle sequence of an arbitrary train which is not limited to periodical or specific (conventional, articulated, regular or standard) trains and which does not include any bridge parameters. The final solution in frequency domain is obtained as the product of these three complex, strongly varying spectra for the dominating bridge mode or in general as the sum of these products over all relevant bridge modes. The time domain solution is obtained via the inverse Fourier transform, and the resulting time histories have been successfully compared with some measurement results. The method is applied to the vertical and torsional modes of a mid-long 1-span bridge on elastomeric bearings under standard train speeds, and to a long multi-span integral bridge under long periodical freight trains. Different resonance and cancellation effects have been found for systematically varied train speeds according to the axle sequence of the whole train which is dominated by the two locomotives in that case. To be more specific, the first torsional mode of the mid-span bridge is excited for a train speed of 100 km/h whereas the second bending mode is excited for a train speed of 160 km/h. In both cases, the other mode is suppressed by the minima of the axle-distance spectra. In addition, the case of the German high-speed train ICE4 and the very high-speed hyperloop case will be discussed briefly. In general, it is shown that resonance effects are also worth to be studied for freight and passenger trains with lower speeds. T2 - XII International Conference on Structural Dynamics CY - Delft, The Netherlands DA - 03.07.2023 KW - Railway bridge KW - Transfer function KW - Modal force spectrum KW - Axle-sequence spectrum KW - Freight train KW - Passenger train KW - High-speed train KW - 2-span bridge KW - Long-span bridge PY - 2023 SP - 1 EP - 10 PB - TU Delft CY - Delft AN - OPUS4-57961 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz T1 - Train-induced ground vibrations - the emission and transmission from tunnel and surface lines N2 - Train-induced ground vibrations are quite different for tunnel and surface lines. The excitation of the track and ground vibration by the vehicle-track-soil interaction maybe influenced by the stiffer track support of the tunnel invert. The excited waves are propagating on a different path compared to the surface line. The wave propagation in the interior of the soil is calculated by a wavenumber integral in a similar way as the propagation along the surface and a general reduction of < 0.5 has been found. An additional reduction has been found because of the missing Rayleigh wave. The different excitation of tunnel lines is analysed theoretically by the combined finite-element boundary-element method and some results about the influencing tunnel and soil parameters will be shown. Measurements have been made at the Mühlberg-Tunnel in Germany. The vibrations of the train, the track and the soil have been measured simultaneously at the tunnel and a nearby surface line. Spectra will be shown for different train speeds between 60 and 160 km/h. A clear reduction effect for the tunnel line compared to the surface line has been observed in a specific (train-speed-dependent) frequency range. This agrees well with the observations of other research institutes. The mid-frequency tunnel-surface reduction seems to be a consequence of the stiffer track structure which leads to a wider distribution of the axle loads. Therefore, the axle impulses due to the train passage are longer and have a lower frequency content. This will have an effect on the ground vibrations at some distance which are present in case of an irregular transmission path through a ballast and soil with varying stiffness. A similar reduction effect can also be found for other track forms where the axle impulses are distributed on a longer track segment, for example slab tracks, tracks with under ballast plates, under ballast mats or under sleeper pads. T2 - 29th International Congress on Sound and Vibration CY - Prague, Czech Republic DA - 09.07.2023 KW - Ground vibration KW - Railway tunnel KW - Layered soil KW - Surface-tunnel reduction KW - Measurements PY - 2023 SP - 1 EP - 8 PB - IIAV CY - Auburn, USA AN - OPUS4-57962 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Costard, René A1 - Agasty, Amit A1 - Kadoke, Daniel A1 - Kind, Thomas A1 - Hicke, Konstantin A1 - Hüsken, Götz T1 - Charakterisierung der Belastung und Schädigung von Stahlbetonprüfkörpern unter Explosionsbeanspruchung N2 - Zur Bewertung der Widerstandsfähigkeit von Schutzobjekten und Bauteilen gegen Explosionsbeanspruchung führt die Bundesanstalt für Materialforschung und -prüfung (BAM) regelmäßig Sprengversuche im Realmaßstab auf einem Testgelände durch. Solche Versuche sind planungs- und ressourcenintensiv, sodass sie zunehmend durch numerische Simulationen ergänzt bzw. ersetzt werden. Aktuelle Forschungsarbeiten zielen darauf ab, neue Berechnungsmethoden und Materialmodelle zu entwickeln, mit denen die Bestimmung der Bauteilantwort sowie die daraus resultierende Schädigung nach einem Explosionsereignis möglich sind. Zur Validierung solcher Ansätze ist es notwendig, systematische Versuche mit unterschiedlichen Szenarien durchzuführen, bei denen die relevanten Parameter mit Hilfe verschiedener Messmethoden aufgezeichnet werden. T2 - 44. Informationstagung Sprengtechnik CY - Siegen, Germany DA - 14.04.2023 KW - Explosivstoff KW - Explosionswirkung KW - Stahlbeton KW - Faseroptische Sensorik PY - 2023 SN - 0941 - 4584 VL - 45 IS - 2 SP - 11 EP - 14 AN - OPUS4-58109 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz T1 - Impacts between different drop masses and different targets in different scales N2 - The Federal Institute of Material Research and Testing has performed many impact tests from very small laboratory tests to very big “free-field” tests with heavy containers on stiff foundations. The first measurements have been done on a big foundation where it should be guaranteed that the foundation is rigid and the container is tested properly. Later on, a smaller drop test facility has been built on the ground inside an existing building. It had to be controlled by prediction and measurements that the drop test will not damage the building. Tests from different heights on soft, medium, and stiff targets have been done to find out rules which allow to identify acceptable and unacceptable drop tests. Later on, the biggest drop test facility has been built for masses up to 200 t. It was necessary for the design of the foundation to estimate the forces which oc-cur during the drop tests. In addititon, the acceptable tests should be selected and controlled by measurements where the impact duration is important. Dif-ferent sensors, accelerometers, accelerometers with mechanical filters, geo-phones (velocity transducers), strain gauges, and pressure cells have been ap-plied for these tasks. Signal transformations and model calculations have been used to check and understand the dynamic measurements. The simplest law is the conservation of the momentum which is a good approximation if the impact is short. If the soil under the foundation has an influence on the deceleration of the container, the maximum foundation velocity is lower than the simple esti-mation. T2 - 10th International Conference on Experimental Vibration Analysis for Civil Engineering Structures CY - Milano, Italy DA - 30.08.2023 KW - Drop test KW - Vibration measurements KW - Container loading KW - Foundation load PY - 2023 AN - OPUS4-58504 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz T1 - Impacts Between Different Drop Masses and Different Targets in Different Scales N2 - The Federal Institute of Material Research and Testing has performed many impact tests from very small laboratory tests to very big “free-field” tests with heavy containers on stiff foundations. The first measurements have been done on a big foundation where it should be guaranteed that the foundation is rigid and the container is tested properly. Later on, a smaller drop test facility has been built on the ground inside an existing building. It had to be controlled by prediction and measurements that the drop test will not damage the building. Tests from different heights on soft, medium, and stiff targets have been done to find out rules which allow to identify acceptable and unacceptable drop tests. Later on, the biggest drop test facility has been built for masses up to 200 t. It was necessary for the design of the foundation to estimate the forces which oc-cur during the drop tests. In addititon, the acceptable tests should be selected and controlled by measurements where the impact duration is important. Dif-ferent sensors, accelerometers, accelerometers with mechanical filters, geo-phones (velocity transducers), strain gauges, and pressure cells have been ap-plied for these tasks. Signal transformations and model calculations have been used to check and understand the dynamic measurements. The simplest law is the conservation of the momentum which is a good approximation if the impact is short. If the soil under the foundation has an influence on the deceleration of the container, the maximum foundation velocity is lower than the simple esti-mation. T2 - Experimental Vibration Analysis for Civil Engineering Structures (EVACES 2023) CY - Milano, Italy DA - 30.08.2023 KW - Drop test KW - Vibration measurements KW - Container loading KW - Foundation load PY - 2023 SN - 978-3-031-39116-3 DO - https://doi.org/10.1007/978-3-031-39117-0_60 SN - 2366-2557 SP - 592 EP - 602 PB - Springer Nature Switzerland CY - Cham, Schweiz AN - OPUS4-58503 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hicke, Konstantin A1 - Chruscicki, Sebastian A1 - Breithaupt, Mathias A1 - Costard, René A1 - Kind, Thomas A1 - Hüsken, Götz A1 - Agasty, Amit T1 - Measuring Dynamic Behavior and Damage Evolution of a Reinforced Concrete Wall Subjected to Explosive Blasts using Embedded Distributed Fiber Optic Sensors N2 - Results from highly dynamic and static strain measurements, respectively, using embedded distributed fiber optic sensors in a steel-reinforced concrete wall under explosive blast-loading are presented, detailing the structure’s dynamic behavior and the evolutions of cracks. T2 - 28th International Conference on Optical Fiber Sensors (OFS-28) CY - Hamamatsu, Japan DA - 20.11.2023 KW - Distributed acoustic sensing KW - DAS KW - Structural response KW - Blast experiment KW - Embedded fiber optic sensor PY - 2023 SP - 1 EP - 4 PB - Optica CY - Washington D.C., USA AN - OPUS4-59096 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Agasty, Amit A1 - Costard, René T1 - Dynamic response of reinforced concrete (RC) components in scaled-down blast tests N2 - Current capabilities for full-scale field testing are highly resource intensive. Reliable small-scale experiments are an effective alternative. Characterization of the dynamic response and damage of RC elements to scaled blast loads was investigated in scaled-down field experiments. Spatially resolved information on the dynamic structural response using distributed fiber optic acoustic sensing (DAS) and acceleration as well as blast loading by piezoelectric pressure sensors. T2 - 45. Informationstagung Sprengtechnik CY - Siegen, Germany DA - 05.04.2024 KW - Blast tests KW - Reinforced concrete KW - Acceleration sensors PY - 2024 AN - OPUS4-59808 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Seifert, Lando T1 - Committee Meeting to WIPANO Research Project "Safety of Prestressing Steel" N2 - This WIPANO research project, "safety of prestressing steel," is about applying the test methods for assessing the susceptibility of prestressing steels to stress corrosion cracking (SCC) according to DIN EN ISO 15630-3. The talk gives an overview of the project's current status to the international committee that accompanies the project. T2 - Committee Meeting to WIPANO Research Project "Safety of Prestressing Steel" CY - Online meeting DA - 12.11.2020 KW - Prestressing Steel KW - Stress corrosion cracking KW - SCC KW - DIN EN ISO 15630-3 KW - Test Methods PY - 2020 AN - OPUS4-51594 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Müller, Thoralf T1 - Ergebnisse des Ringversuchs zur Integration der DIN 55635 in die DIN 50937 N2 - Die Präsentation zeigt die Motivation und die Ergebnisse des Ringversuchs gemäß DIN 55635 an Zinkblechen. Die dort bestimmten Abtragsraten dienen der Aufnahme der DIN 55635 in die Vergleichsnorm 50937. T2 - Sitzung des Normausschusses NA 062-01-77 AA CY - Online meeting DA - 28.10.2020 KW - Korrosion KW - Korrosionswechselprüfung KW - Zink KW - Stahl KW - Normung PY - 2020 AN - OPUS4-51481 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Müller, Thoralf T1 - Ergebnisse des Ringversuchs zur Integration der DIN 55635 in die DIN 50937 N2 - Die Präsentation stellt die Hintergründe und die Ergebnisse des Ringversuchs zur DIN 55635 an Reinzinkblechen vor. Die Ergebenisse dienen der Aufnahme der DIN 55635 in die Vergleichnorm DIN 50937. T2 - Sitzung des Normausschusses NA 062-01-71 AA CY - Online meeting DA - 27.10.2020 KW - Korrosion KW - Korrosionswechselprüfung KW - Zink KW - Stahl KW - Normung PY - 2020 AN - OPUS4-51480 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Müller, Thoralf T1 - Nichtrostende Stähle - Passivität ist naturgemäß aber unter welchen Bedingungen stabil ? N2 - Der Vortrag behandelt die Passivität von nichtrostenden Stählen. Es werden Ausführungen zur Passivschichtbildung und deren Kinetik gemacht. Weiterhin werden lokale Korrosionsarten näher erläutert und deren Mechanismen erklärt. An praktischen Beispielen werden inner und äussere Einflussfaktoren auf die Passivität und Korrosionsbeständigkeit von nichtrostenden Stählen näher beleuchtet und erklärt. T2 - fkks infotag 2021 CY - Online meeting DA - 14.01.2021 KW - Korrosion KW - Passivität KW - Nichtrostender Stahl KW - Lochkorrosion KW - Spaltkorrosion PY - 2021 AN - OPUS4-52008 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Müller, Thoralf T1 - Ergebnisse des Ringversuchs zur Integration der DIN 55635 in die DIN 50937 N2 - Die Präsentation zeigt die Motivation und die Ergebnisse des Ringversuchs gemäß DIN 55635 an Zinkblechen. Die dort bestimmten Abtragsraten dienen der Aufnahme der DIN 55635 in die Vergleichsnorm 50937. T2 - Sitzung der Ad-hoc Gruppe "Ringversuch DIN 55635" CY - Online meeting DA - 15.12.2020 KW - Korrosion KW - Klimawechseltest KW - Zink KW - Korrosionsprüfung PY - 2020 AN - OPUS4-51864 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Müller, Thoralf T1 - Korrosion und Korrosionsschutzverfahren Teil 2: Korrosionsschutzverfahren N2 - Dieser Vortrag erläutert die verschiedenen Korrosionsschutzmethoden, welche sich aus den grundlegendem Verständnis der Korrosion ableiten lassen. So werden korrosionsschutzgerechte Kontruktionen, die Asuwahl geeigneter Werkstoffe und die Vermeidung von galvanischen Elementen erläutert. Unterstützt werden die verschiedenen Themengebiete mit Praxisbeispielen. T2 - TAE Seminar Kathodischer Korrosionsschutz - Grundlagenkurs für erdverlegte Anlagen, Stahlbeton und Innenschutz CY - Online meeting DA - 09.02.2021 KW - Korrosion KW - Korrosionsschutz KW - Beschichtung KW - Überzüge KW - Passivität PY - 2021 AN - OPUS4-52103 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Müller, Thoralf T1 - Korrosion und Korrosionsschutzverfahren Teil 1: Korrosion metallener Werkstoffe N2 - Dieser Vortrag behandelt die Grundlagen der Korrosion metallener Werkstoffe. Es wird die Triebkraft der Korrosion, die Teilreaktionen sowie die messtechnische Bestimmung der Korrosionsgeschwindigkeit beschrieben. Weiterhin werden Korrosionselemente wie Konzentrationselemente und Bimetallkorrosion näher erläutert. T2 - TAE Seminar Kathodischer Korrosionsschutz - Grundlagenkurs für erdverlegte Anlagen, Stahlbeton und Innenschutz CY - Online meeting DA - 09.02.2021 KW - Korrosion KW - Metallene Werkstoffe KW - Korrosionselemente KW - Bimetallkorrosion KW - Korrosionsschutz PY - 2021 AN - OPUS4-52102 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Müller, Thoralf T1 - Projektvorstellung Wipano Vorhaben Spanntahlsicherheit N2 - Diese Präsentation stellt das WIPANO Vorhaben Spanntahlsicherheit vor, welches von der BAM in Kooperation mit dem Stahlwerks Annahütte und der Max Aicher GmbH bearbeitet wird. Es werden die Projektziele näher beleuchtet und verschiedentliche Highlights der bisherigen Untersuchungsergebnisse vorgestellt. T2 - Arbeitskreissitzung des GfKorr-Arbeitskreises Eisen und Stahl CY - Online meeting DA - 22.06.2021 KW - Korrosion KW - Spannstahl KW - Spannbetonbauwerke KW - Spannungsrisskorrosion KW - Wasserstoffversprödung PY - 2021 AN - OPUS4-52863 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schraut, Katharina T1 - Hydraulic reactivity of alite rich material from post-treated basic oxygen furnace slags N2 - Basic oxygen furnace slags (BOFS) are a by-product of steel production. In 2016, 10.4 Mt of BOFS were produced in the European Union (EU). The main part of BOFS is used in road construction, earthwork and hydraulic engineering. A smaller part is returned to the metallurgical circle, used as fertilizer or landfilled. However, it is also possible to produce higher value products from BOFS. For example, many researchers have investigated the possibility of producing Portland cement clinker and crude iron from BOFS by a carbothermal post-treatment. In this study, German BOFS was reduced in a small-scale electric arc furnace using petrol coke as reducing agent. The carbothermal treatment reduces the iron oxides in the BOFS to metallic iron, which accumulates at the bottom of the furnace by density separation. In addition to metallic iron, the process generates a mineral product rich in the tricalcium silicate solid solution alite. As the main constituent of Portland cement clinker, the hydraulic reactive mineral alite is of high economic importance. In previous studies, the hydraulic reactivity of the mineral product was investigated by testing the compressive strength of blends with 70 wt.% ordinary Portland cement (OPC). Recent investigations focused on the hydraulic properties of the pure mineral product from the reduced BOFS. The heat of hydration of the mineral product was measured by isothermal calorimetry and compared with the heat of hydration of a synthetic low-iron slag and OPC. In addition, the formation of hydration products was investigated with differential scanning calorimetry (DSC) and x-ray diffraction analysis (XRD) on freeze-dried samples after defined curing times. The results of the calorimetric measurements indicate that the mineral product produced less heat of hydration and its reaction was delayed compared to the synthetic low-iron slag and OPC. Hydration products such as portlandite and calcium silicate hydrates (C-S-H) formed later and in lower amounts. The production of a hydraulic material from BOFS by reductive treatment is of great interest to both the cement and steel industries. The substitution of cement clinker in OPC with a hydraulic material such as reduced BOFS leads to a reduction in greenhouse gas emissions from cement production. The steel industry benefits from an application for its by-products that avoids cost expensive landfilling and may even bring economic advantages. Furthermore, it may be possible to return the recovered crude iron to production. T2 - 3rd European Mineralogical Conference CY - Cracow, Poland DA - 30.08.2021 KW - BOFS KW - Calcium silicate KW - Hydraulic reactivity PY - 2021 AN - OPUS4-53473 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Seifert, Lando T1 - The Development of a new Test Method for assessing the Susceptibility of Prestressing Steels to HiSCC N2 - This EUROCORR 2021 talk gives current results of the WIPANO research project "safety of prestressing steels." The project targets improving DIN EN ISO 15630-3 according to the reproducibility and scattering of constant load tests to assess the susceptibility of prestressing steels to stress corrosion cracking. Essential questions which we answered in the talk was: Are test practical on surfaces in delivery condition? What are the hydrogen activities of test solutions A and B during free corrosion and cathodic polarization? Can the test be improved by a modification of the test cell dimensions? T2 - Virtual EUROCORR 2021 CY - Online meeting DA - 20.09.2021 KW - Prestressing steels KW - Corrosion KW - Test electrolytes KW - DIN EN ISO 15630-3 KW - Stress corrosion cracking KW - Hydrogen charging KW - Permeation measurements PY - 2021 AN - OPUS4-53325 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Müller, Thoralf A1 - Seifert, Lando A1 - Ebell, Gino T1 - Projektvorstellung Wipano Vorhaben Spanntahlsicherheit N2 - Diese Präsentation stellt das WIPANO Vorhaben Spanntahlsicherheit vor, welches von der BAM in Kooperation mit dem Stahlwerks Annahütte und der Max Aicher GmbH bearbeitet wird. Es werden die Projektziele näher beleuchtet und verschiedentliche Highlights der bisherigen Untersuchungsergebnisse vorgestellt. T2 - DIN-Ausschussitzung des NA 062-01-77 AA "Korrosionsprüfverfahren" CY - Online meeting DA - 21.10.2021 KW - Korrosion KW - Spannstahl KW - Spannbetonbauwerke KW - Spannungsrisskorrosion KW - Wasserstoffversprödung PY - 2021 AN - OPUS4-53588 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schraut, Katharina T1 - Portland cement clinker from reduced basic oxygen furnace slag N2 - Basic oxygen furnace slag (BOFS) is a by-product of the steelmaking process, of which about 10.4 Mt are produced annually in the European Union. Besides its predominant use in road construction, earthwork, and hydraulic engineering, it is also possible to use BOFS as a source material for Portland cement clinker. The main difference in the chemical composition of BOFS from the chemical composition of Portland cement clinker is its high content of iron oxides (7-50 wt.%). In recent decades, many researchers have investigated the production of both Portland cement clinker and crude iron from BOFS via thermochemical reductive treatment. Carbothermal treatment of liquid BOFS causes reduction of iron oxides to metallic iron, which separates from the mineral phase due to its higher density. In this study, German BOFS was reduced in a small-scale electric arc furnace using petrol coke as reducing agent. The produced low-iron mineral product was chemically similar to Portland cement clinker and contained the most important Portland cement mineral alite (Ca3SiO5) as main component. Besides alite, the mineral product contained other Portland cement clinker constituents such as belite (β-Ca2SiO4) and tricalcium aluminate (Ca3Al2O6). The production of Portland cement clinker and crude iron from BOFS has economic and ecological benefits for both the cement and steel industry. Cement clinker from reduced BOFS may be used as a substitute for cement clinker from conventional cement production, thereby CO2 emissions will be reduced. The steel industry benefits from a high-value application for its by-products that avoids cost expensive landfilling and may even bring economic advantages. However, reductive treatment requires high temperatures and, for economic reasons, has to be carried out immediately after casting of the liquid BOFS, which is a logistical challenge for most steel plants. A cost-benefit analysis is therefore essential. T2 - European Congress and Exhibition on Advanced Materials and Processes CY - Online meeting DA - 13.09.2021 KW - BOFS KW - Portland Cement KW - Hydraulic reactivity PY - 2021 AN - OPUS4-53475 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Seifert, Lando A1 - Müller, Thoralf T1 - WIPANO Projekt zur Spannstahlprüfung N2 - Das WIPANO-Projekt Spannstahlsicherheit wurde mit aktuellen Ergebnissen im Fachgremium der Gesellschaft für Korrosionsschutz e.V. (GfKORR) im Arbeitskreis Eisen und Stahl vorgestellt. Das Projekt hat die Verbesserung der produktspezifischen Prüfnorm ISO 15630-3 als Ziel. Vorgestellt und diskutiert wurden Aspekte des Oberflächeneinflusses, der Wasserstoffaktivität, Veränderung der Messzelle und die Anpassung des Korrosionstests durch kathodische Polarisierung. T2 - Konferenz der GfKORR Korrosion und Korrosionsschutz von Eisen und Stahl CY - Online meeting DA - 14.12.2021 KW - Korrosion KW - Spannbetonbauwerke KW - Spannstahl KW - Spannungsrisskorrosion KW - Wasserstoffversprödung KW - ISO 15630-3 PY - 2021 AN - OPUS4-54056 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Müller, Thoralf T1 - Kurzbericht aus den DIN Ausschüssen N2 - Der Vortrag gibt einen Überblick über die Tätigkeiten der DIN-Ausschüsse "Korrosionsprüfverfahren" sowie "Korrosion und Korrosionsschutz". Es werden neuste Informationen zum Stand verschiedener Normen aus den beiden Ausschüssen gegeben. T2 - Arbeitskreissitzung des GfKorr-Arbeitskreises Korrosionsuntersuchung und -überwachung CY - Online meeting DA - 08.12.2021 KW - Korrosion KW - Korrosionsschutz PY - 2021 AN - OPUS4-54085 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Burkert, Andreas T1 - Bedingungen für den schadensfreien Einsatz von nichtrostenden Stählen N2 - Unter Passivität versteht man den Korrosionsschutz durch dünne, festhaftende Schichten aus Korrosionsprodukten. Für den schadensfreien Einsatz nichtrostender Stähle ergeben sich daraus zwei grundsätzliche Anforderungen. Erstens muss sich die Passivschicht vollständig ausbilden können. Dabei sind die Oberflächenausführung, die mechanische Bearbeitung, die Elementverteilung, Ausscheidungen, die Wärmeeinbringung z.B. bei der schweißtechnischen Verarbeitung, Anlauffarben, sowie die chemische Nachbehandlung bzw. Konditionierung der Oberflächen von großer Bedeutung. Zweitens muss die Repassivierung von Defektstellen unter den Einsatzbedingungen möglich sein. Für das Repassivierungsvermögen sind die Legierungszusammensetzung, mögliche kritische Betriebszustände, prozessbedingte Besonderheiten, wie etwa Stagnationsbedingungen und Reinigungsprozesse von Bedeutung. T2 - Nichrostende Stähle - Eigenschaften und Anwendung CY - Düsseldorf, Germany DA - 01.06.2022 KW - Korrosion KW - Werkstoffauswahl KW - Dauerhaftigkeit PY - 2022 AN - OPUS4-54989 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Seifert, Lando T1 - Safety of Prestressing Steels N2 - This talk reports the findings of the WIPANO "Knowledge and Technology Transfer via Patents and Standards" research project "Safety of Prestressing Steels," founded by the German Ministry of Economic Affairs and Climate Action (BMWK). A new test method for assessing the susceptibility of prestressing steels to hydrogen-induced stress corrosion cracking (SCC) is presented, which serves the demands of a lower scattering compared with the present standard. Moreover, the ability to differentiate between high susceptible and low susceptible prestressed wires is possible, modifying the method by hydrogen charging and surface preparation. T2 - Konferenz EUROCORR 2022 CY - Berlin, Germany DA - 28.08.2022 KW - ISO 15630-3 KW - Stress Corrosion Cracking KW - Prestressing Steels KW - Hydrogen KW - Constant Load Test PY - 2022 AN - OPUS4-55661 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Müller, Thoralf A1 - Ebell, Gino T1 - Grundlagen der Korrosion N2 - Darstellung der Grundlagen der elektrochemischen Korrosion von metallenen Werkstoffen im Bauwesen. Dabei liegt das Hauptaugenmerk auf dem Zusammenhang zwischen Energieaufwand für den Herstellungsprozess und daraus resultierendem thermodynamisch instabilen Zustand und Korrosionsneigung. Der Einfluss der Deckschicht- Oxidschichtbildung wird ebenfalls behandelt. T2 - Sachkundelehrgang zur Durchführung von Potentialfeldmessungen 2022 CY - Baruth/Mark, Germany DA - 16.05.2022 KW - Korrosion KW - Potentialfeldmessung PY - 2022 AN - OPUS4-54868 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Babutzka, Martin T1 - Field exposure studies under sheltered and unsheltered conditions at different test sites in northern and eastern Germany: Update after 5 years of exposure N2 - A series of field exposure tests according to ISO 9223 up to 9226 was carried out at different locations to determine the corrosivity and the corrosion progress of different test sites throughout northern and eastern Germany. Standard test specimens of steel, zinc, copper and aluminium were exposed to rural, city and marine atmosphere at test sites of the Bundesanstalt für Materialforschung und -prüfung (BAM). Test sites at city atmosphere comprised exposure on a rooftop, next to a highly frequented road and directly at a motorway. Exposure under marine conditions was carried out at Heligoland in the North Sea. The specimens were stored under sheltered and unsheltered conditions on each test site, respectively. Corrosion rates after the first year of field exposure were determined and used for the classification of the atmospheres and the test sites regarding the corrosivity category. Results after the first year of exposure were presented at the EUROCORR 2018 in Cracow. The current presentation will present an update of results of the systematic study after five years of exposure. The corrosion progress and the mass loss of the standard metals steel, zinc, copper and aluminium will be presented and discussed with respect to the atmospheric conditions and the time of wetness at the test sites. In addition, the difference between sheltered and unsheltered conditions will be discussed. T2 - EUROCORR 2022 CY - Berlin, Germany DA - 28.08.2022 KW - Atmospheric Corrosion KW - Atmosphärische Korrosion KW - Korrosionsuntersuchungen KW - Corrosion testing PY - 2022 AN - OPUS4-55602 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Seifert, Lando T1 - Committee Meeting to WIPANO "Safety of Prestressing Steels" N2 - A conclusion on the WIPANO research project "Safety of Prestressing Steel" was presented in the final committee meeting at the end of the project. The project's exciting findings and recommendations for a new method were discussed with the audience of national and international stakeholders of the prestressing steel industry and representatives of inspection bodies and standardization. T2 - Committee Meeting to WIPANO research Project CY - Online meeting DA - 29.09.2022 KW - ISO 15630-3 KW - Prestressing Steels KW - Hydrogen-induced Stress Corrosion Cracking KW - Hydrogen PY - 2022 AN - OPUS4-56101 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Müller, Thoralf T1 - Vorstellung Projektergebnisse Wipano Vorhaben Spanntahlsicherheit N2 - Diese Präsentation stellt die Ergebnisse des abgeschlossenen WIPANO Vorhabens "Spannstahlsicherheit" vor, welches von der BAM in Kooperation mit dem Stahlwerks Annahütte und der Max Aicher GmbH bearbeitet wird. Es werden die Projektziele näher beleuchtet und verschiedentliche Highlights der erzielten Untersuchungsergebnisse vorgestellt. T2 - DIN-Ausschussitzung des NA 062-01-77 AA "Korrosionsprüfverfahren" CY - Berlin, Germay DA - 19.10.2022 KW - Korrosion KW - Spannstahl KW - Spannbetonbauwerke KW - Spannungsrisskorrosion KW - Wasserstoffversprödung PY - 2022 AN - OPUS4-56059 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Müller, Thoralf T1 - Abschlussvorstellung Wipano Vorhaben Spanntahlsicherheit N2 - In dem Vortrag werden die Highlights und Ergebnisse des abgeschlossenen Wipano Forschungsprojekts "Spannstahlsicherheit" berichtet. In dem Vorhaben wurde das Projektziel ein neues Prüfverfahren für die Prüfung von Spannstählen auf Spannungsrisskorrosionsempfindlichkeit zu entwickeln erfolgreich abgeschossen. Weiterhin wurden neue Erkenntnisse zu den Ursachen der Ergebnisstreuung der bisherigen Prüfung gemäß ISO 15630-3 gewonnen. Das neue Prüfverfahren soll bei der nächsten Überarbeitungsrunde der ISO 15630-3 als Verfahren zunächst in den informativen Anhang aufgenommen werden. T2 - Arbeitskreissitzung des GfKorr-Arbeitskreises Eisen und Stahl CY - Online meeting DA - 08.12.2022 KW - Korrosion KW - Spannstahl KW - Spannbetonbauwerke KW - Spannungsrisskorrosion KW - Wasserstoffversprödung PY - 2022 AN - OPUS4-56510 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Burkert, Andreas T1 - Sinn und Unsinn der Wirksumme bei Nichtrostenden Stählen N2 - Anhand der Wirksumme ist eine Abschätzung des legierungsabhängigen Einflusses auf den Korrosionswiderstand gegen chloridhaltige Medien möglich. Die berechneten Werte sind nur bei optimaler Wärmebehandlung und Verarbeitung zutreffend. Die Anwendung einer einfachen Formel unter Berücksichtigung von Chrom, Molybdän und Stickstoff ist in der Regel völlig ausreichend. Das daraus abgeleitete Ranking von Werkstoffen ist für diverse technische Regelwerke und zur Unterstützung der Werkstoffauswahl geeignet. Für die Warenein-/Ausgangskontrolle ist die alleinige Feststellung der Wirksumme unzureichend. Ergänzende Korrosionsuntersuchungen/-prüfungen zur Beschreibung des Korrosionswiderstandes sind dafür notwendig. Gleiches gilt für die Beurteilung von Schadensfällen. Hier sind Verarbeitung, Einsatzbedingungen und die Konstruktion von ausschlaggebender Bedeutung. T2 - fkks Infotag: Charakteristische Kennwerte zur Einschätzung des Korrosionsschutzes CY - Online meeting DA - 12.01.2023 KW - Wirksumme KW - Korrosion KW - Nichtrostende Stähle PY - 2023 AN - OPUS4-56821 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Müller, Thoralf T1 - Mehr als Chrom-Nickel - Alternative nichtrostende Stähle und ihre Anwendungspotentiale N2 - In diesem Vortrag werden die Hintergründe, Ziele und ausgewählte Ergebnisse aus dem IGF-Vorhaben zu Korrosionsuntersuchungen an alternativen nichtrostenden Stählen vorgestellt. Weiterhin werden die Vorteile dieser Stähle hinsichtlich mechanisch -technologischer Eigenschaften sowie deren Kosten gegenüber den klassischen austenitischen nichtrostenden Stählen aufgezeigt. T2 - GfKORR Jahrestagung 2022 CY - Frankfurt am Main, Germany DA - 08.11.2022 KW - Korrosion KW - Nichtrostende Stähle KW - Duplexstähle KW - Lochkorrosion KW - Festigkeit PY - 2022 AN - OPUS4-56197 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Seifert, Lando T1 - Grundlagen Korrosion und Korrosionsschutz - Teil 1: Korrosion metallener Werkstoffe N2 - Innerhalb der Fachausbildung "Kathodischer Korrosionsschutz (KKS)" wurde dieser Vortrag im Grundlagenkurs für erdverlegte Anlagen, Stahlbeton und Innenschutz gehalten. Der 90 min Vortrag befasste sich schwerpunktmäßig mit den Grundlagen der elektrochemischen Korrosion von wichtigen Metallen im Bauwesen: Unleg. Stahl, Aluminium- und Zinkwerkstoffen sowie nichtrostenden Stählen. Galvanische Elemente sowie die Grenzen der elektrochemischen Potentialmessung wurden besprochen. Dies wird anhand einer Reihe von Beispielen verdeutlicht. Der Vortag knüpft die Verbindung zwischen den grundlegenden Korrosionsreaktionen, den äußeren Umgebungsbedingungen, der Korrosionsgeschwindigkeit, dem Faraday'schen Gesetz und den elektrochemischen Stromdichte-Potential-Kurven, mit denen in der Korrosionswissenschaft gearbeitet wird. T2 - Grundlagenkurs für erdverlegte Anlagen, Stahlbeton und Innenschutz; Fachausbildung "Kathodischer Korrosionsschutz (KKS)" CY - Online meeting DA - 28.02.2023 KW - Korrosion KW - Elektrochemische Korrosion KW - Potentialmessung KW - Galvanische Korrosion KW - Bimetallkorroison PY - 2023 AN - OPUS4-57068 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Burkert, Andreas T1 - Korrosionsarten an geschweißten Bauteilen aus Cr-Ni-Stahl N2 - Die Bedingungen für den schadensfreien Einsatz nichtrostender Stähle, nicht nur bei Schweißverbindungen, sind: 1) Die Passivschicht muss sich vollständig ausbilden können. Voraussetzung dafür sind glatte, blanke, saubere Oberfläche, eine gleichmäßige Elementverteilung, wenig Ausscheidungen und Verunreinigungen. Eine mögliche Beeinflussung der Gefügeausbildung durch Warmumformung und durch die schweißtechnische Verarbeitung sind zu beachten. Anlauffarben müssen durch geeignete geeignete chemische bzw. mechanische Nachbehandlung entfernt werden. 2) Die Repassivierung von Defektstellen unter Einsatzbedingungen muss möglich sein, was durch geeignete Werkstoffauswahl und die Legierungszusammensetzung sicherzustellen ist. Unplanmäßige Betriebszustände oder Störungen können kritische Systemzustände hervorrufen, die die Repassivierung beeinträchtigen oder verhindern. Eine geeignete Unterhaltsreinigung ist sicherzustellen. T2 - Weiterbildung DVS Bezirksverband Chiemgau CY - Trostberg, Germany DA - 02.03.2023 KW - Nichtrostender Stahl KW - Korrosionsverhalten KW - Verarbeitung KW - Fehlerquellen PY - 2023 AN - OPUS4-57150 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Gluth, Gregor T1 - Reinforcing steel in sulfide-containing concretes – corroding or not corroding? N2 - Blast furnace cements (CEM III) and alkali-activated slags are binders for concretes with several advantageous engineering properties, and their increased adoption in construction industry could contribute to reducing the CO2 emissions associated with cement production and use. However, the current knowledge about how these cements protect steel reinforcement in concretes against corrosion is very incomplete, which impedes their large-scale application. This knowledge gap is mainly due to the fact that these cements release sulfide and other reduced sulfur species into the concrete pore solution, the consequences of which for the state of the reinforcement and electrochemical measurements are not fully understood. The present contribution first describes peculiarities of electrochemical measurements of steel in sulfide-containing cementitious materials and related solutions as reported in the literature and a recent report by EFC Working Party 11. It is demonstrated that the high sulfide concentrations in these systems lead to low open circuit potentials and low polarisation resistances, which may be incorrectly interpreted as indicating active corrosion of the steel. Second, preliminary results of an ongoing project [funded by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) – 458297195] related to the passivation and corrosion initiation of steel in sulfide-containing solutions and mortars are presented. Eight mortars based on one alkali-activated blast furnace slag (BFS), three alkali-activated BFS/fly ash blends, one sodium sulfate-activated CEM III/C (‘hybrid cement’), one CEM III/C, one CEM III/B, and one CEM I (ordinary Portland cement, OPC) were produced, and their pore solutions expressed and analysed after 7, 14, 28, and 56 days of curing. The pH values of the solutions differed systematically, with the highest pH values recorded for the CEM I and the alkali-activated BFS/fly ash blends with a high proportion of fly ash, and the lowest pH recorded for the CEM III/B. The redox potentials of the solutions were between −500 mV and −340 mV vs. Ag/AgCl for the alkali-activated binders, approx. +10 mV vs. Ag/AgCl for the CEM I, and in between for the CEM III/B and the CEM III/C. As expected, the electrical conductivity was highest for the alkali-activated binders. These results are explained by the chemical compositions of the pore solutions of the mortars. Finally, a test set-up to investigate the behaviour of steel in sulfide-containing solutions and the changes on subsequent oxygen and/or chloride addition is introduced. Preliminary electrochemical measurements of steel in sulfide-containing solutions are presented and discussed in the context of the above-mentioned data from the literature and the compositions of the pore solutions of the studied mortars. T2 - 7th Swiss Corrosion Science Day 2023 CY - Zurich, Switzerland DA - 24.04.2023 KW - Reinforcing steel KW - Sulfide KW - Concrete KW - Ground granulated blast furnace slag KW - Corrosion PY - 2023 AN - OPUS4-57386 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Müller, Thoralf A1 - Ebell, Gino T1 - Grundlagen der Korrosion N2 - Durch das alkalische Milieu des Porenwassers im Beton ist der Stahl normalerweise dauerhaft vor Korrosion geschützt. Unter ungünstigen Umgebungsbedingungen (Chlorideintrag, Carbonatisierung) kann die passive Deckschicht auf der Stahloberfläche zerstört werden. Der Korrosionsprozess ist initiiert. Die entstehenden Korrosionsprodukte werden zunächst vom Porengefüge des Betons aufgenommen, ohne dass es zu sichtbaren Schäden am Bauwerk führt. Im fortgeschrittenem Stadium der Korrosion können sich dann Risse und Abplatzungen bilden. Um notwendige Sanierungsmaßnahmen sowohl aus sicherheitstechnischen Gründen als auch aus wirtschaftlichen Erwägungen rechtzeitig einzuleiten, sind frühzeitige und weitestgehend zerstörungsfreie Prüfverfahren zur Ermittlung der aktuellen Korrosionswahrscheinlichkeit der Stahlbewehrung von großer Bedeutung. Deshalb finden Methoden und Verfahren zur laufenden bzw. regelmäßigen Korrosionsüberwachung von Stahlbetonbauwerken ständig größere Beachtung, sowohl im Bereich Forschung und Entwicklung als auch in der Praxis. Die elektrochemische Potentialfeldmessung ist ein etabliertes und weit verbreitetes Verfahren zur Beurteilung des Korrosionszustandes der Bewehrung in Stahlbetonbauwerken. Mit Hilfe dieses Verfahrens können Bereiche korrodierender Bewehrung zerstörungsfrei lokalisiert werden. In der Regel kommt diese Methode bei der Detektion von chloridinduzierter Korrosion zum Einsatz. Der Lehrgang vermittelt den Teilnehmenden in kompakter Form einen zusammenfassenden Überblick über die notwendigen Grundlagen zum Verständnis der Messmethode, der Vorbereitung und Durchführung der Messungen, der notwendigen Begleituntersuchungen sowie der Interpretation der gewonnenen Daten. Der erste Tag ist der theoretischen Ausbildung gewidmet, am zweiten Tag folgt dann die praktische Anwendung der Lerninhalte. Am dritten Tag folgt die Abnahme der praktischen und theoretischen Prüfung zur Erlangung des Sachkundenachweises. T2 - Sachkundelehrgang zur Durchführung von Potentialfeldmessungen CY - Berlin, Germany DA - 24.04.2023 KW - Potentialfeldmessung KW - Korrosion PY - 2023 AN - OPUS4-57493 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Müller, Thoralf T1 - Projektvorstellung Gefügeveränderung bei trockener Schleifbearbeitung N2 - Der Vortrag stellt die Projektskizze zum Thema Gefügeveränderung bei trockener Schleifbearbeitung vor. Das Projekt hat das Ziel, das sich aus dem Trockenschleifverfahren ergebende chemische, mechanische und thermische Belastungskollektiv in der Kontaktzone zwischen Schleifmittel und Stahloberfläche in Abhängigkeit der verwendeten Schleifparameter genau zu beschreiben und die daraus resultierenden Oberflächen- und Gefügeveränderungen zu identifizieren und zu klassifizieren. T2 - Jahrestagung der Forschungsgemeinschaft Schleifen (FGS) 2023 CY - Würzburg, Germany DA - 30.03.2023 KW - Korrosion KW - Trockenschleifen KW - Mikrostruktur KW - Stahl KW - Nichtrostender Stahl PY - 2023 AN - OPUS4-57256 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Auersch, Lutz T1 - Reduction in Train-Induced Vibrations—Calculations of Different Railway Lines and Mitigation Measures in the Transmission Path N2 - The reduction in train-induced ground vibrations by different railway lines and by mitigation measures in the propagation path was analysed in a unified approach by two-dimensional finite element calculations. In general, there was no reduction at low frequencies, and the reduction be-came stronger with increasing frequencies. A maximum reduction of 0.1 at high frequencies was established with an open trench. Reductions between 0.7 and 0.2 have been found for the other sit-uations, filled trenches, walls, plates, and blocks, as well as for railway lines on dams, in cuts and in a tunnel. Bridges can produce amplifications due to their resonance frequencies, but also strong reductions due to massive bridge piers. The influence of some parameters has been analysed, such as the bridge span, the inclination of the dam and the cut, the stiffness of the soil, and the tunnel structure. The dynamic track stiffnesses of a surface, bridge, and tunnel track have been calculated using the 3D finite-element boundary-element method for comparison with corresponding meas-urements. KW - Train-induced vibration KW - Mitigation KW - Trench KW - Obstacles KW - Tunnel KW - Bridge KW - Finite element KW - Boundary element PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-579573 DO - https://doi.org/10.3390/app13116706 VL - 13 IS - 11 SP - 1 EP - 19 PB - MDPI CY - Basel AN - OPUS4-57957 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Auersch, Lutz T1 - Site-specific amplitude-distance laws, wave velocities, damping, and transfer functions of the soil from hammer impacts and application to railway-induced ground vibration – Similarities and mid-frequency differences N2 - The propagation of ground vibrations is theoretically analysed with frequency-wavenumber and simplified methods. Experimental methods are presented which can characterise the site-specific ground vibrations by wave velocities, stiffness and damping. Measurements with hammer and train excitation have been performed at several sites. The one-third octave spectra show the stiffness-dependent amplitudes and the low- and high-frequency filter effects due to the layering and the damping of the soil. Specific train effects, an additional high-frequency filter, the sleeper passage frequency, and an amplified mid-frequency component can be clearly found. The attenuation with distance is analysed in detail where the theoretical exponential and the empirical frequency-dependent power law are considered. Hammer and train excitation show the same site-specific effects which are mainly due to the stronger or weaker damping of the soil. The train attenuation is generally weaker than the hammer attenuation. The attenuation exponent of the power law, which is strongly dependent on the site and the frequency, is reduced for the train vibration by 0.3 to 0.5 in agreement with the theory. Reasons are discussed for the overall power law and for the dominating mid-frequency component. KW - Hammer impact KW - Train passage KW - Layered soil KW - Attenuation KW - Filter effects KW - Randomly heterogeneous soil KW - Scattering PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-585020 DO - https://doi.org/10.1007/s42417-023-01095-0 SN - 2366-2557 SP - 1 EP - 17 PB - Springer AN - OPUS4-58502 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Auersch, Lutz A1 - Song, Jiaojiao T1 - Dynamic damage detection of slab tracks – finite element models on Winkler soil and finite-element boundary-element models on continuous soil N2 - The train passages over intact or damaged slab tracks on different soils have been calculated by two methods. The finite element method (FEM) uses a Winkler soil under the track model by adding a thin “soil layer”. The combined finite element boundary element method has a continuous soil model which is included by the boundary element method. The basic results are the distributions of the track (rail, track plate, and base layer) displacements along the track for a single axle laod. These solutions are superposed to a complete train load and transformed to time histories. The influence of track and soil parameters has been analysed. The main interest is the influence of the track damage. A gap between track plate and base layer of different lengths has been studied for changes in amplitudes and widths of deflection. A best fit to measured track displacements has been found so that the track damage can be identified and quantified. The FEM model with Winkler soil cannot be fitted to the amplitude and width with the same soil parameters. Therefore, the FEBEM model is preferable for these railway track problems. KW - Track damage quantification KW - Finite element method KW - Combined finite-element boundary-element method PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-562207 DO - https://doi.org/10.3390/civileng3040055 SN - 2673-4109 VL - 3 IS - 4 SP - 979 EP - 997 PB - MDPI CY - Basel AN - OPUS4-56220 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz T1 - Characteristic Frequencies of Train-Induced Bridge, Track, Ground and Building Vibrations – Excitation and Mitigation N2 - The characteristic frequencies of train-induced vibrations are discussed in theory and experiment following the propagation of vibrations from the source to the receiver: 1. Out-of-roundness frequencies of the wheels, 2. sleeper-passage frequency, 3. the vehicle-track eigenfrequency, 4. band frequency of the impulses of the passing static axle loads, 5. car-length frequency and multiples, 6. axle-distance frequencies with two characteristic zeros, 7. bridge eigenfrequencies, 8. the cut-on frequency due to the layering, and 9. the cut-off frequency due to the material damping of the soil, 10. the building-soil eigenfrequency, 11. as a rigid building or flexible wall/column mode, 12. floor eigenfrequencies, 13. acoustic room resonances, 14. the „resonance“ frequency or cut-off frequency of a base isolation. Coincidences of some of these characteristic frequencies or frequency ranges can be typically problematic and mitigation measures at the track or at the building can be necessary. The bridge response to the passing static loads is deter¬mined by the axle-sequence spectrum, the eigenfrequency (transfer function) of the bridge, and the modal force or mode shape spectrum. The ground vibration has typically high frequencies for a stiff soil and low frequencies for a soft soil. The high amplitudes between the zeros of the axle-sequence spectrum are often measured in the ground vibrations, and they can be mitigated by soft support elements or a higher bending stiffness of the track. T2 - EVACES 2025 CY - Porto, Portugal DA - 02.07.2025 KW - Train-induced vibration KW - Vehicle excitation KW - Track response KW - Bridge resonance KW - Ground vibration KW - Soil-building transfer KW - Floor resonance KW - Axle-sequence spectrum KW - Vehicle-track eigenfrequency KW - Axle impulses PY - 2025 SN - 978-3-031-96113-7 VL - 2025 SP - 1 EP - 8 PB - Springer CY - Cham, Schweiz AN - OPUS4-63655 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Agasty, Amit A1 - Costard, Rene A1 - Kadoke, Daniel A1 - Kind, Thomas A1 - Hicke, Konstantin A1 - Hüsken, Götz T1 - A comprehensive experimental assessment of reinforced concrete walls under blast: In situ monitoring of loading, dynamic response and damage with NDT methods and embedded sensors N2 - A safety or security related assessment of explosions, accidental and intentional scenarios alike, often necessitate performance of resource intensive replication tests. For an efficient assessment without performing full scale blast tests, e.g., supported by numerical simulations, detailed knowledge is necessary to predict the blast loading from a given charge configuration, the resulting dynamic response of the structure under investigation as well as the resulting damage. Validation of numerical simulation requires the spatially resolved acquisition of all these parameters in real time. In this paper we present a set of measurement techniques and discuss their suitability for monitoring reinforced concrete (RC) walls under blast loading. Different blast-loading scenarios were realized by varying the charge weight and the standoff distance. The dynamic loading of the wall was characterized with pressure sensors complemented by numerical simulations using the APOLLO Blastsimulator and ConWep. High speed digital image correlation (DIC) was implemented in combination with multiple acceleration sensors to observe the dynamic deflection of the walls during the loading and to determine the residual deformation after the loading had ceased. In addition, one test specimen was instrumented with fiber optic sensor cables. These fiber optic sensors were used for distributed acoustic sensing (DAS) delivering information on dynamics of compression and tension cycles from within the structure. Additionally, the local damage pattern emerging during the series of blasts was determined via distributed fiber optic strain sensing (DSS) to enable the characterization of visual and non-visual damage to the structure. The obtained information was compared to results by an ultrasound structure-scanner. KW - Blast testing KW - Reinforced concrete KW - NDT methods KW - Fiber optic sensing KW - DIC KW - Numerical simulations KW - APOLLO Blastsimulator PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-638320 DO - https://doi.org/10.1177/20414196251353795 SN - 2041-4196 SP - 1 EP - 31 PB - Sage Publications AN - OPUS4-63832 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Seifert, Lando A1 - Müller, Thoralf A1 - Bettge, Dirk A1 - Moersch, Jörg A1 - Isecke, Bernd A1 - Ebell, Gino T1 - Stress Corrosion Tests for Prestressing Steels—Part 2: Susceptibility of Quenched and Tempered Wires—Influence of Chromium N2 - Due to the risk of failure in existing prestressed concrete bridges, the assessment of the susceptibility of prestressing steel to hydrogen‐induced stress corrosion cracking will become more important in the future. At present, the used normative ISO 15630‐3 test gives unpersuasive and diverging results using a free corrosion approach for the needed hydrogen charging for stress corrosion cracking initiation. A newly developed test method uses the cathodic polarization to control the supply of electrons for hydrogen charging instead of an uncontrolled and variable supply of electrons by metal dissolution during free corrosion. Experimental data shows a reliable differentiation between highly susceptible known quenched and tempered wires and robust cold‐drawn wires with this new test. A round robin with eight participating testing institutes demonstrated the reproducibility of results testing a cold‐drawn wire batch of St 1470/1670. In contrast to previously reported experience in the literature, the new method ranks the Cr‐alloyed quenched and tempered (“new‐type”) wires as highly‐susceptible as the “old‐type” wires without Cr‐alloy. KW - Cathodic polarization KW - Chemical composition KW - Chromium KW - Prestressing steels KW - Quenched and tempered KW - Stress corrosion cracking KW - Susceptibility KW - Wires PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-639735 DO - https://doi.org/10.1002/maco.70033 SN - 0947-5117 SP - 1 EP - 10 PB - Wiley-VCH CY - Weinheim AN - OPUS4-63973 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Liao, Chun-Man A1 - Niederleithinger, Ernst A1 - Bernauer, F A1 - Igel, H A1 - Hadziioannou, Céline T1 - Wave-Screening Methods for Prestress-Loss Assessment of a Large-Scale Post-Tensioned Concrete Bridge Model Under Outdoor Conditions N2 - This paper presents advancements in structural health monitoring (SHM) techniques, with a particular focus on wave-screening methods for assessing prestress loss in a large-scale prestressed concrete (PC) bridge model under outdoor conditions. The wave-screening process utilizes low-frequency wave propagation obtained from seismic interferometry of structural free vibrations and high-frequency wave propagation obtained through ultrasonic transducers embedded in the structure. An adjustable post-tensioning system was employed in a series of experiments to simulate prestress loss. By comparing bridge vibrations under varying post-tensioning forces, the study investigated prestress loss and examined temperature-related effects using the coda wave interferometry (CWI) method. Local structural alterations were analyzed through wave velocity variations, demonstrating sensitivity to bridge temperature changes. The findings indicate that wave-based methods are more effective than traditional modal analysis for damage detection, highlighting the dual impacts of prestress loss and temperature, as well as damage localization. This study underscores the need for long-term measurements to account for temperature fluctuations when analyzing vibration measurements to investigate changes in prestressing force in PC structures. KW - Coda wave interferometry KW - Damage detection KW - Prestress loss KW - Seismic interferometry KW - SHM KW - Temperature influence KW - Ultrasonics KW - Wave-screening PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-634244 UR - https://www.mdpi.com/2076-3417/15/11/6005 DO - https://doi.org/10.3390/app15116005 VL - 15 IS - 11 SP - 1 EP - 18 PB - MDPI AN - OPUS4-63424 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Zhang, Kun A1 - Kong, Deyu A1 - Schmidt, Wolfram A1 - Mezhov, Alexander T1 - Influence of hydroxypropylation of starch on rheological properties of cement paste modified by superplasticizers N2 - Starch is often used as a viscosity modifying agent (VMA) in self-compacting concrete (SCC) and highly flowable concrete. In this paper, starches possessing different degrees of hydroxypropyl substitution (DS) were used to study the shear rheological properties and hydration kinetics of cement paste in the presence of and without polycarboxylate superplasticizer (PCE). The starch with the highest DS increases the yield stress and the plastic viscosity stronger than others. Regardless of the dosage and DS of starch the structural build-up is not affected specifically by the starch during the induction period. During the acceleration period starches reduce the structural build-up, but with the highest DS this effect was less prominent than for the other modifications. In the presence of PCE the addition of starch notably increases the yield stress, whereas the influence on the plastic viscosity is limited. Yet, the combined application of PCE and starch allows to control rheological properties and maintain the structural build-up rate. KW - Modified starch KW - PCE KW - Structural build-up KW - Rheological properties KW - Cement hydration PY - 2025 DO - https://doi.org/10.1016/j.conbuildmat.2025.143646 SN - 1879-0526 VL - 495 SP - 1 EP - 13 PB - Elsevier CY - Amsterdam AN - OPUS4-64168 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Ramirez Caro, Alejandra A1 - Pauli, Jutta A1 - Mota, Berta A1 - Simon, Sebastian A1 - Schmidt, Wolfram A1 - Resch-Genger, Ute T1 - C⁠3A passivation with gypsum and hemihydrate monitored by optical spectroscopy N2 - Tricalcium aluminate (C⁠3A) is found with less than 10% wt. of the total composition; however, during hydration, C⁠3A plays an important role in the early hydration of cement in the presence of gypsum as a set retarder. The aim of this investigation is to assess the suitability of optical spectroscopy and a dye-based optical probe to monitor early hydration of C⁠3A in the presence of gypsum and hemihydrate. Optical evaluation was performed using steady-state fluorescence and diffuses reflectance spectroscopy (UV-VisDR). Phase characterization during hydration was done with in-situ X-ray diffraction. UV-VisDR with a cyanine dye probe was used to monitor the formation of metastable phases and was employed together with fluorescence spectroscopy, to follow the Aggregation and disaggregation of the dye during hydration. In conclusion, for the first time, a cyanine dye was identified as a feasible and stable probe to monitor C⁠3A hydration changes in the presence of calcium sulfate. KW - Dye KW - Photoluminescence KW - Fluorescence KW - Reflection spectroscopy KW - Cement KW - Hydration KW - Method development PY - 2020 DO - https://doi.org/10.1016/j.cemconres.2020.106082 VL - 133 SP - 106082 PB - Elsevier Ltd. CY - Amsterdam AN - OPUS4-50952 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Oesch, Tyler T1 - Proposed Project SealWasteSafe: Materials Technology, Quality Assurance and Monitoring Techniques for Safe Sealing Systems in Underground Repositories N2 - The proposed BAM project SealWasteSafe will advance the state of the art for the construction and monitoring of safe sealing systems for underground repositories of radioactive or toxic waste. During this project, a novel salt concrete exhibiting neither significant cracking nor shrinkage will be optimized for use in the sealing systems. The composition of this material will be based on alkali-activated materials, which are characterized by particularly small thermal deformations during the hardening reaction. Quality assurance and continuous monitoring systems developed during this project will be demonstrated not only for high reliability, but also for resistance to highly alkaline environments and to water intrusion along cables or at sensor locations. A variety of sensors will be used in combination with wireless Radio Frequency Identification (RFID) technology to record moisture, temperature, and, if necessary, corrosion activity within the sealing system. Distributed Fibre Optic Sensor (FOS) technology will also be used for strain, temperature, and moisture content measurement. Ultrasound-based measuring methods will be utilized for the detection of cracks and delaminations. Additionally, digital image correlation and acoustic emission analysis will be used for deformation measurements and crack detection. A novel borehole probe and advanced ultrasound imaging techniques will be further developed to track cracks and delaminations within the host rock in 3D. The surface-based Large Aperture Ultrasound System (LAUS) will also be utilized to detect cracks and delaminations deep below the exterior surface of the sealing system. Although the focus of this project will be on the host rock salt, the resulting technologies will be intentionally developed in a way that facilitates their adaptation to other host rocks. T2 - 2nd International Conference on Monitoring in Geological Disposal of Radioactive Waste CY - Paris, France DA - 09.04.2019 KW - SealWasteSafe KW - Radioactive Waste Disposal KW - Underground Repositories KW - Alkali-Activated Material KW - Monitoring PY - 2019 AN - OPUS4-47776 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ramirez Caro, Alejandra T1 - The Effect of Low Charge Polycarboxylate on C3A Passivation Monitored by Optical Spectroscopy N2 - Tricalcium aluminate (C3A) is less than 10 wt.% of the total cement composition; however, during hydration, the soluble C3A plays an important role in cement setting when mixed with the appropriate amount of sulfate.1 A good understanding about the balance of these components is therefore crucial to follow with the rapid growth of substitution materials and the rising levels of aluminate clinker. The aim of this investigation is the use of optical spectroscopy and in-situ X-ray diffraction utilizing a water-soluble organic dye (dye-S) to monitor early hydration of calcium aluminate (C3A) in the presence of 26 wt.% CaS04.2H2O (G) and PCE polymers with different charge densities (PCE-LC and PCE-HC). Phase characterization and optical evaluation were performed using in-situ X-ray diffraction and steady-state fluorescence and diffuse reflectance spectroscopy. Fluorescence spectroscopy of the reference C3A + dye-S revealed a fast decay in fluorescence intensity. However, in the presence of 26 wt.% G (C3A + dye-S + 26 wt.% G), a gradual increase in fluorescence intensity was observed in the first hours of reaction followed by a plateau that subsequently dropped in intensity after eight hours. The addition of PCE-LC and PCE HC to the mixture exhibited changes in the intensity threshold and overall a higher fluorescence intensity. Dye changes during hydration and structural changes will be further discussed. T2 - 3rd International Conference on Polycarboxylate Superplasticizers (PCE 2019) CY - Munich, Germany DA - 23.10.2019 KW - Dye KW - C3A KW - Optical Spectroscopy KW - Gypsum PY - 2019 AN - OPUS4-49343 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ramirez Caro, Alejandra T1 - Use of Optical Spectroscopy to Monitor Cement Hydration and Additive Effect N2 - Use of optical spectroscopy and fluorescence reporter (DFFL and dye-S) to visualize the effects of additives on the hydration of cement pastes as a fast, sensitive and monitoring method. T2 - Beirat Tagung CY - Berlin, Germany DA - 26.04.2019 KW - Cement KW - Optical Spectroscopy KW - Dye KW - Hydration KW - Superplasticizer PY - 2019 AN - OPUS4-49349 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Altmann, Korinna A1 - Wimmer, Lukas A1 - Alcolea-Rodriguez, Victor A1 - Waniek, Tassilo A1 - Wachtendorf, Volker A1 - Matzdorf, Kay A1 - Ciornii, Dmitri A1 - Fengler, Petra A1 - Milczewski, Frank A1 - Otazo-Aseguinolaza, Itziar A1 - Ferrer, Manuel A1 - Bañares, Miguel A. A1 - Portela, Raquel A1 - Dailey, Lea Ann T1 - Quality-by-design and current good practices for the production of test and reference materials for micro- and nano-plastic research N2 - Understanding the environmental and human health impacts of micro- and nanoplastic pollutants is currently a high priority, stimulating intensive methodological research work in the areas of sampling, sample preparation and detection as well as intensive monitoring and testing. It is challenging to identify and quantify microplastics in complex organic matrices and concepts for nanoplastic detection are still in their infancy. All analytical techniques employed in studying micro- and nanoplastics require suitable reference materials for validation measurements, with requirements as diverse as the analytical tools used, ranging from different polymer types, size distributions and shapes of the material to the concentrations employed in different experimental set ups (ng to g amounts). The aim of this manuscript is to outline current good practices for small-scale laboratory production and characterization of suitable test and reference materials. The focus is placed on top-downfragmentation methods as well as bottom-up precipitation methods. Examples using polyethylene, polypropylene, polystyrene and polyethylene terephthalate with size distribution classes of mainly 10–1000, 1–10 and <1 μm particles will be provided. Experiences and suggestions on how to produce well-characterized micro- and nano-plastics for internal research needs will ensure that studies using the materials have robust and informative outcomes. KW - Mmicroplastics KW - Nanoplastics KW - Reference materials KW - Standard validation method PY - 2025 DO - https://doi.org/10.1016/j.jhazmat.2025.139595 SN - 0304-3894 VL - 497 SP - 1 EP - 20 PB - Elsevier B.V. AN - OPUS4-63958 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Aristia, Gabriela A1 - Bäßler, Ralph A1 - Nofz, Marianne A1 - Sojref, Regine A1 - Kohl, Anka T1 - Short-term exposure tests of ɣ-Al2O3 Sol-gel coating on X20Cr13 in artificial geothermal waters with different pH N2 - The suitability of an Al2O3 coating for corrosion protection on X20Cr13 was evaluated in various artificial geothermal brines, focusing on the influence of different pH (4, 6 and 8) and their chemical compositions on the coating properties. All experiments were performed in the laboratory using autoclaves at 150 ◦C and 1 MPa in deaerated condition for 1 and 7 days. Results showed that the pH of geothermal waters is the most detrimental factor in the transformation of ɣ-Al2O3 and its protective abilities. Delaminations were found in the Coating exposed to geothermal brines with pH 4. FTIR spectra indicated a transformation of ɣ-Al2O3 to boehmite AlOOH after exposure to pH 4 and 6, and bayerite Al(OH)3 was formed after exposure to pH 8. Different Crystal structures of the hydrated Al2O3 also contribute to the stability of the coatings, observed by the SEM- EDX of the surface and cross-section of coatings. This study indicated that ɣ-Al2O3 sol-gel coating presents a promising aspect of corrosion protection in geothermal environment with a neutral pH. KW - Al2O3 KW - Corrosion KW - Coating KW - Martensitic steel PY - 2021 DO - https://doi.org/10.1016/j.geothermics.2021.102193 SN - 0375-6505 VL - 96 SP - 102193 PB - Elsevier Ltd. CY - Amsterdam AN - OPUS4-52931 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Zinas, Orestis T1 - CPT-based probabilistic analysis of monopile foundations considering spatial and transformation uncertainties N2 - This study utilizes cone penetration testing data data from a real offshore windfarm project in the North Sea and presents a method for incorporating both, statistical and spatial uncertainties, in a reliability-based assessment of monopile foundations. Initially, a Gaussian Process regression model is constructed to predict a 3D map of the cone tip resistance and the associated uncertainties in the predictions and the hyperparameters, leveraging Markov Chain Monte Carlo methods. The CPT-based prediction is combined with a correlation derived from data collected at a nearby site to predict the probability distribution of the friction angle at a test location, which is subsequently used to evaluate the probability of failure for a monopile foundation with a finite element model. T2 - 9th International Symposiumon Geotechnical Safety and Risk (ISGSR) CY - Oslo, Norway DA - 25.08.2025 KW - Monopile design KW - Cone Penetration Test KW - Gaussian process regression KW - Bayesian Inference PY - 2025 AN - OPUS4-64001 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Anderson, J. A1 - Boström, L. A1 - Chiva, R. A1 - Guillaume, E. A1 - Colwell, S. A1 - Hofmann-Böllinghaus, Anja A1 - Toth, P. T1 - European approach to assess the fire performance of façades N2 - Several attempts have been made in the past to develop a European harmonized testing and assessment method for façades before the European commission decided to publish a call for tender on the topic. A project consortium from five countries (Sweden, UK, France, Germany and Hungary) applied to the call for tender and was contracted to develop a European approach to assess the fire performance of façades. 24 sub-contractors and 14 stakeholder entities were part of the project. The objective of the European project was to address a request from the Standing Committee of Construction (SCC) to provide EC Member States regulators with a means to regulate the fire performance of façade systems based on a European Approach agreed by SCC. The initial stages of this Project were focused on establishing a Register of the regulatory requirements in all Member States in relation to the fire Performance of façade systems, and to identify those Member States who have regulatory requirements for the fire performance façade systems which go beyond the current EN 13501 (reaction to fire and fire resistance) classification systems and to collate the details of these additional requirements. After having confirmed the regulatory needs a testing and classification methodology based on BS 8414 and DIN 4102-20 was developed to address the identified key performance and classification characteristics. This paper is a short overview of results the two-year development work, which Final Report published by the European Commission in 2018. KW - Facade KW - Regulation KW - Testing PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-530501 DO - https://doi.org/10.1002/fam.2878 SN - 1099-1018 VL - 45(5) IS - Special issue: Facade fire safety SP - 598 EP - 608 PB - Wiley CY - Oxford AN - OPUS4-53050 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR ED - Hofmann-Böllinghaus, Anja ED - Anderson, J. T1 - Special issue: Facade fire safety N2 - Façade fires are of growing concern worldwide. Severe facade fires in different parts of the world as well as activities in many countries regarding the testing of facades show the urgency of the fire safety challenges in façade fires. The need for knowledge and a wide Archive of work in this area has become evident after recent incidents which involved extensive facade fires. These include the tragic fires in Dubai and Grenfell Tower in 2017 in the United Kingdom. In many cases, the widespread live news coverage of the events and size of These fires has emphasized the need for progress in the understanding of the processes involved in these fires and put pressure upon the fire safety engineering community to find effective solutions. KW - Testing KW - Safety PY - 2021 UR - https://onlinelibrary.wiley.com/toc/10991018/2021/45/5 SN - 0308–0501 SN - 1099-1018 VL - 45 IS - 5 SP - 583 EP - 696 PB - Wiley CY - Oxford AN - OPUS4-53102 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Wu, Hongyi T1 - Influence of local vegetation on ignition and fire spread of vegetation fires-Experimental and numerical approach N2 - To investigate the influence of local vegetation, it goes through two aspects. One is laboratory study, the local vegetation samples were collected and tested for the thermal properties, such as activation energy, heat content and reaction kinetic of pyrolysis and dehydration. At the same time, small and medium scale combustion experiments were conducted to investigate the burning behavior. The other aspect is using the thermal properties as the input parameters for the development of numerical simulation in the computational fluid dynamics (CFD) tool. These models were then be validated with the combustion experiments, as a baseline for the further scaling up of the models, in order to investigate how the parameters influencing the fire spread in a large-scale case numerically. T2 - Interflam 2025, 16th International Fire Science and Engineering Conference CY - London, United Kingdom DA - 30.06.2025 KW - Wildfire PY - 2025 AN - OPUS4-63933 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Geoerg, Paul A1 - Berchtold, Florian A1 - Gwynne, Steven A1 - Boyce, Karen A1 - Holl, Stefan A1 - Hofmann-Böllinghaus, Anja T1 - Engineering egress data considering pedestrians with reduced mobility N2 - To quantify the evacuation process, evacuation practitioners use engineering egress data describing the occupant movement characteristics. These data are typically based to young and fit populations. However, the movement abilities of occupants who might be involved in evacuations are becoming more variable—with the building populations of today typically including increasing numbers of individuals: with impairments or who are otherwise elderly or generally less mobile. Thus, there will be an increasing proportion of building occupants with reduced ability to egress. For safe evacuation, there is therefore a need to provide valid Engineering egress data considering pedestrians with disabilities. Gwynne and Boyce recently compiled a series of data sets related to the evacuation process to support practitioner activities in the chapter Engineering Data in the SFPE Handbook of Fire Protection Engineering. This paper supplements these data sets by providing information on and presenting data obtained from additional research related to the premovement and horizontal movement of participants with physical-, cognitive-, or age-related disabilities. The aim is to provide an overview of currently available data sets related to, and key factors affecting the egress performance of, mixed ability populations which could be used to guide fire safety engineering decisions in the context of building design. KW - Disability KW - Egress KW - Evacuation PY - 2019 DO - https://doi.org/10.1002/fam.2736 SN - 0308–0501 SN - 1099-1018 VL - 43 IS - 7 SP - 759 EP - 781 PB - Wiley CY - London, UK AN - OPUS4-48833 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Webb, A. A1 - Hofmann-Böllinghaus, Anja T1 - Changes in façade regulations N2 - Recent facade fires worldwide have driven change in regulations for façade fire safety in different parts of the world. The Grenfell Tower fire 2017 in London triggered a thorough investigation of many aspects of the fire. One investigation was about the UK building regulations from Dame Judith Hackett. This investigation compares the UK with the situation other parts of the world. Key findings of the review of building regulations by Judith Hackett are: T2 - Interflam 2019 CY - London, UK DA - 01.07.2019 KW - Facades PY - 2019 VL - 2019 SP - 213 EP - 228 PB - Interscience CY - London, UK AN - OPUS4-49893 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Gnutzmann, Tanja A1 - Hahn, S.-K. T1 - Charakterisierung von Entstehungsbränden N2 - Im Rahmen des BMBF geförderten Verbundprojekts „TEBRAS – Konzepte und Techniken zur Branderkennung, Bekämpfung und Selbstrettung in der frühesten Brandphase“ arbeiten sechs Partner aus der Wissenschaft und der Industrie gemeinsam an Lösungen zur schnelleren Branddetektion und Bekämpfung. Ausgehend von Brandschadenstatistiken werden zunächst häufige Brandentstehungsszenarien, Brandursachen und die beteiligten Objekte und Materialien identifiziert. Auf dieser Basis wird ein Testszenario entwickelt, das es erlaubt, einen repräsentativen Entstehungsbrand unter definierten Testbedingungen zu untersuchen. Typische Brandkenngrößen werden anhand der ausgewählten Referenzszenarios des Schwelbrands einer Mischbrandkrippe vorgestellt. Der Fokus liegt dabei auf den freigesetzten Brandgasen. T2 - vfdb Jahresfachtagung 2019 CY - Ulm, Germany DA - 27.5.2019 KW - Detektion KW - Frühe Brandphase PY - 2019 SN - 978-3-936050-31-8 VL - 2019 SP - 184 EP - 200 PB - VdS Schadenverhütung CY - Köln AN - OPUS4-48662 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Gnutzmann, Tanja T1 - Charakterisierung von Entstehungsbränden N2 - Im Rahmen des BMBF geförderten Verbundprojekts „TEBRAS – Konzepte und Techniken zur Branderkennung, Bekämpfung und Selbstrettung in der frühesten Brandphase“ arbeiten sechs Partner aus der Wissenschaft und der Industrie gemeinsam an Lösungen zur schnelleren Branddetektion und Bekämpfung. Ausgehend von Brandschadenstatistiken werden zunächst häufige Brandentstehungsszenarien, Brandursachen und die beteiligten Objekte und Materialien identifiziert. Auf dieser Basis wird ein Testszenario entwickelt, das es erlaubt, einen repräsentativen Entstehungsbrand unter definierten Testbedingungen zu untersuchen. Typische Brandkenngrößen werden anhand der ausgewählten Referenzszenarios des Schwelbrands einer Mischbrandkrippe vorgestellt. Der Fokus liegt dabei auf den freigesetzten Brandgasen. T2 - vfdb Jahresfachtagung 2019 CY - Ulm, Germany DA - 27.5.2019 KW - Detektion PY - 2019 AN - OPUS4-48663 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Klippel, Andrea T1 - Quantitative risk analysis and numerical investigations to determine critical fire scenarios in the environment of handicapped people N2 - Crisis management, particularly the evacuation of handicapped people during a fire scenario presents a highly demanding challenge for nursing staff and rescue forces on site. The German research Project SiME is an interdisciplinary cooperation of university and non-university research institutions as well as medium-sized companies, which work together to develop strategies to manage such critical scenarios. In the SiME project, which is funded by the German Federal Ministry of Education and Research, evacuation characteristics of pedestrians with physical, mental or age-related disabilities are investigated to fit consisting numerical evacuation models with data. One of the major tasks of the OvGU was to set up a database of scenarios related to fire, explosion or substance releases in the working and living environment of handicapped people. Therefore, more than 463 fire Events occurring over the last decade in Germany were documented in this database and categorized by a suitable assignment of characteristics e.g. location of fire, ignition source, number of fatalities and injured. T2 - Interflam 2019 CY - London, UK DA - 1.07.2019 KW - Evacuation PY - 2019 AN - OPUS4-48650 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Geoerg, Paul T1 - Sicherheit für Menschen Beeinträchtigung bei der Evakuierung – Ein Bericht aus der Forschung N2 - Evakuierungsübung Werkstatt: positives Ergebnis Evakuierungsübung Wohnbereich: Optimierungspotential identifiziert •Lange Evakuierungszeiten •Vorzeitige Rückkehr in das Gebäude / Freigabe •Gefährdungsbeurteilungen •Einweisung / regelmäßige Übung Assistenzmittel •Intensivierung der Zusammenarbeit / Abstimmung mit örtlicher Feuerwehr T2 - Abschlußveranstaltung des BMBF Verbundprojekts SiME CY - Wermelskirchen, Germany DA - 14.05.2019 KW - Evakuierung PY - 2019 AN - OPUS4-48654 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Gnutzmann, Tanja T1 - Analysis of fire gases in early stages N2 - A promising approach for the further improvement of fire detection techniques is the inclusion of fire gases in the characteristics used to detect a fire. A screening of sample materials representative for common first burning items and their gas release under different ignition conditions was performed to gain an overview of possible target gas candidates. Different fire scenarios were investigated to evaluate fire gases produced in early stages of fire development, their time of appearance and concentration development using the vitiated mass loss calorimeter and a heating plate setup in the single burning item test chamber. T2 - Interflam 2019 CY - London, UK DA - 01.07.2019 KW - Detection PY - 2019 AN - OPUS4-48664 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Geoerg, Paul T1 - The influence of individual impairments on crowd dynamics N2 - Emergency exits as bottlenecks in escape routes are important for designing traffic facilities. Especially the fundamental diagram is a crucial performance criterion for assessment of pedestrians' safety in facilities and an important basis for calculation methods. For this reason, several studies were performed during the last decades which focus on the quantification of movement through bottlenecks. These studies were usually conducted with populations of homogeneous characteristics to reduce influencing variables and for reasons of practicability. Studies which consider heterogeneous characteristics in performance parameters are rarely available. In response and to reduce this lack of data a series of well-controlled large-scale movement studies considering pedestrians with different disabilities was carried out. T2 - Interflam 2019 CY - London, UK DA - 1.07.2019 KW - Evacuation PY - 2019 AN - OPUS4-48653 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Klippel, A. A1 - Hofmann-Böllinghaus, Anja A1 - Piechnik, K. A1 - Gnutzmann, Tanja T1 - Development of toxicity assessment method for bus interior materials N2 - In recent years, fire safety requirements for bus interior materials have been increased and introduced into international regulations. Fire safety requirements for the burning rate, melting and dripping behaviour of interior materials already exist for many years. However, it remains unclear to what extent the release of smoke, combustion products and their toxicity should be limited. Therefore, a research and development project 82.0723 funded by BASt (Federal Highway Research Institute) was initiated to develop a simplified procedure for testing the toxicity and smoke development in case of fire of interior materials used in buses. The scope of the research included calculations to assess the toxicity of fire gases and the derivation of specifications for the formation of practicable limit values for smoke toxicity. Further investigations are needed to derive these limit values for smoke toxicity in order to be applicable for real fire scenarios in buses. T2 - Conference Fire in Vehicles FIVE CY - Stavanger, Norway DA - 24.04.2023 KW - Bus materials PY - 2023 SP - 80 EP - 90 AN - OPUS4-57627 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hofmann-Böllinghaus, Anja T1 - Europäische Harmonisierung von Brandstatistiken für Wohngebäude N2 - Das EU Projekt EU FireStat SI2.830108, das vom Europäischen Parlament finanziert und von der DG GROW der Europäischen Kommission in Auftrag gegeben wurde, hat aufgearbeitet, welche Terminologie in den europäische Mitgliedsstaaten verwendet wird und die von den Mitgliedstaaten erhobenen Daten über Gebäudebrände zu analysieren. Dabei wurden die Schwierigkeiten bei der Erfassung und die Unterschiede bei der Auslegung ermittelt und eine gemeinsame Terminologie sowie eine Methode zur Erfassung der erforderlichen Daten vorgeschlagen. Folgende Schwerpunkte wurden bearbeitet: Zunächst erfolgte eine Diagnose von Terminologie-, Datenerhebungs- und Auslegungsproblemen, Erhebung der Terminologie und der Datenerfassung, Identifizierung der für die Entscheidungsfindung benötigten Daten, Analyse der Methoden zur Datenerhebung Definition einer gemeinsamen Terminologie, Methodik der Kosten-/Nutzenbewertung zur Unterstützung politischer Entscheidungen, Fallstudie zur Anwendung der Methode der Kosten-/Nutzenbewertung, Beschreibung einer zukünftigen Datenerhebungsmethode. Das Ergebnis des Projekts ist eine Empfehlung, welche Daten in den Mitgliedstaaten erhoben werden sollten, um wissensbasierte Entscheidungen in Bezug auf den Brandschutz zu ermöglichen. Damit wird die Grundlage für Maßnahmen und Initiativen geschaffen, die den Brandschutz und die Brandverhütung der Mitgliedstaaten unterstützen, so dass knappe Ressourcen gezielt eingesetzt werden können. T2 - 69. Jahresfachtagung der Vereinigung zur Förderung des Deutschen Brandschutzes CY - Münster, Germany DA - 15.05.2023 KW - Statistik PY - 2023 SN - 976-3-936050-36-3 VL - 2023 SP - 391 EP - 401 PB - VdS CY - Köln AN - OPUS4-57573 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hofmann-Böllinghaus, Anja T1 - Europäische Harmonisierung von Brandstatistiken für Wohngebäude N2 - Das EU Projekt EU FireStat SI2.830108, das vom Europäischen Parlament finanziert und von der DG GROW der Europäischen Kommission in Auftrag gegeben wurde, hat aufgearbeitet, welche Terminologie in den europäische Mitgliedsstaaten verwendet wird und die von den Mitgliedstaaten erhobenen Daten über Gebäudebrände zu analysieren. Dabei wurden die Schwierigkeiten bei der Erfassung und die Unterschiede bei der Auslegung ermittelt und eine gemeinsame Terminologie sowie eine Methode zur Erfassung der erforderlichen Daten vorgeschlagen. Folgende Schwerpunkte wurden bearbeitet: Zunächst erfolgte eine Diagnose von Terminologie-, Datenerhebungs- und Auslegungsproblemen, Erhebung der Terminologie und der Datenerfassung, Identifizierung der für die Entscheidungsfindung benötigten Daten, Analyse der Methoden zur Datenerhebung Definition einer gemeinsamen Terminologie, Methodik der Kosten-/Nutzenbewertung zur Unterstützung politischer Entscheidungen, Fallstudie zur Anwendung der Methode der Kosten-/Nutzenbewertung, Beschreibung einer zukünftigen Datenerhebungsmethode. Das Ergebnis des Projekts ist eine Empfehlung, welche Daten in den Mitgliedstaaten erhoben werden sollten, um wissensbasierte Entscheidungen in Bezug auf den Brandschutz zu ermöglichen. Damit wird die Grundlage für Maßnahmen und Initiativen geschaffen, die den Brandschutz und die Brandverhütung der Mitgliedstaaten unterstützen, so dass knappe Ressourcen gezielt eingesetzt werden können. T2 - 69. Jahresfachtagung der Vereinigung zur Förderung des Deutschen Brandschutzes CY - Münster, Germany DA - 15.05.2023 KW - Statistik PY - 2023 AN - OPUS4-57574 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hofmann-Böllinghaus, Anja T1 - Feuer und Rauchausbreitung in Busdepots, Brandverhalten von Bussen N2 - Präsentation zur Problemen der Brandsicherheit bei Busdepots und Empfehlungen zur Verbesserung der Brandsicherheit. T2 - Brandschutz von Bus-Betriebshöfen CY - Cologne, Germany DA - 02.05.2023 KW - Brandschutz PY - 2023 AN - OPUS4-57416 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Wu, Hongyi T1 - Untersuchung von Brandausbreitungsmechanismen bei Waldbränden N2 - Das EU Projekt TREEADS „A Holistic Fire Management Ecosystem for Prevention, Detection and Restoration of Environmental Desasters” beschäftigt sich mit der Erforschung der drei Phasen „Prävention und Bereitschaft“, „Detektion und Reaktion“ und „Aufforsten und Anpassen“ der Waldbrandverhütung. Im Projekt gibt es acht ausgewiesene Pilotregionen, in denen Deutschland auch mit einer Pilotregion in Sachsen-Anhalt bzw. in Brandenburg vertreten ist. Unsere Arbeit auf Charakterisierung des Waldbodens und numerische Simulation wird vorgestellt. T2 - vfdb-Jahresfachtagung 2023 CY - Münster, Germany DA - 15.05.2023 KW - Waldbrand KW - Klimawandel KW - Charakterisierung des Waldbodens KW - Numerische Strömungsmechanik PY - 2023 AN - OPUS4-57621 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Wu, Hongyi A1 - Hofmann-Böllinghaus, Anja ED - Makovická Osvaldová, L. ED - Hasburgh, L. E. ED - Das, O. T1 - Applying experimental determined kinetic parameters to the simulation of vegetation fire in the Fire Dynamics Simulator N2 - Although intense wildfire research has been done in the US and in Australia, it cannot be transferred directly to the situation in Europe as the local vegetation has a significant influence on the fire spread. The EU-funded project TREEADS and the so-called German pilot within the project are concentrating on wildfire in Europe. Extensive experimental research is done on local vegeta-tion in Germany and the experimental results are used to adjust the Fire Dynam-ics Simulator (FDS) to local vegetation as a fuel in the calculations. The particle model and the boundary fuel model are developed for the simulation of forest fires. Both models require the kinetic input for the dehydration, pyrolysis, and char oxidation process. This three-step simplified model describes the basic fuel combustion kinetic. Most published simulations use the default kinetic input of pine needles from FDS user manual. To adjust the simulation to local vegetation, the corresponding kinetic parame-ters have been experimental investigated. Samples of pine needles, moss and other falling leaves were collected, air dried and grinded into powder. The TG analysis of all these samples were done under different heating rate of 5, 10 and 20K/min. The activation energy and the corresponding pre-exponential factor were calcu-lated. The results show that fire spread depends significantly on the vegetation and comparison with small scale experiments show good agreement using the new kinetic parameters. The new model is applied to a larger scenario and will be compared to the results of large-scale experiments for further validation of the model. T2 - Wood and Fire Safety 2024 CY - Štrbské Pleso, Slovakia DA - 12.05.2024 KW - Forest KW - Simulation KW - FDS KW - Vegetation fire KW - Fire Dynamics Simulator KW - Kinetic parameters PY - 2024 SN - 978-3-031-59177-8 DO - https://doi.org/10.1007/978-3-031-59177-8_45 SP - 389 EP - 396 PB - Springer CY - Cham AN - OPUS4-60252 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Wu, Hongyi A1 - Hofmann-Böllinghaus, Anja T1 - TREEADS - Experimente und numerische Simulation zur Brandausbreitung von Vegetationsbränden N2 - Um die Ausbreitungsmechanismen von Vegetationsbränden und besonders bei Bodenbränden besser zu verstehen, wurden die Einflussfaktoren auf die Brandausbreitung näher untersucht. Da die Brandausbreitung auch in starkem Maße von der lokalen Vegetation abhängt, war eine Charakterisierung der lokalen Vegetation und der Bodenverhältnisse wichtig. Die Wetterverhältnisse spielen einerseits im Vorfeld des Brandes durch längere Dürreperioden als auch während des Brandes, z.B. durch den Windeinfluss, zusätzlich eine große Rolle. Durch die numerische Simulation kann eine größere Variation der Einflussgrößen abgebildet werden als durch die zeitlich und finanziell begrenzten experimentellen Möglichkeiten. Für die Berechnungen wird der Fire Dynamic Simulators (FDS) mit dem Paket WFDS verwendet. Dadurch kann mit einem vereinfachten 3-Phasen-Reaktionskinetikmodell, bestehend aus Dehydrierung, Pyrolyse, Kohleoxidation, die Ausbreitung von Vegetationsbränden verschiedener Waldbodenarten untersucht werden. Es wurden dazu 6 typische Pflanzenarten und Bodenproben aus Kiefern-, Buchen und Eichenbeständen ausgewählt. Die gesammelten Waldbodenproben wurden alle hinsichtlich des Wassergehalts, des organischen Gehalts, der Packungsdichte, der Dichte und der statistisch ermittelten Pflanzenartenverteilung charakterisiert. Das kinetische Abbrandverhalten wurde durch Thermogravimetrische Analyse (TGA) untersucht. Alle diese Daten wurden als Eingabeparameter für die Simulation verwendet. Die numerischen Simulationen werden mit Experimenten im kleinen, mittleren und Real-Maßstab validiert. T2 - 70. Jahresfachtagung der Vereinigung zur Förderung des Deutschen Brandschutzes CY - Magdeburg, Germany DA - 06.05.2024 KW - Waldbrand KW - Simulation KW - FDS PY - 2024 SN - 978-3-936050-38-7 SP - 321 EP - 336 PB - VdS CY - Köln ET - 2 AN - OPUS4-60258 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hofmann-Böllinghaus, Anja T1 - Challenges in fire safety of facades N2 - To ensure fire safety of facades will keep being a challenge as facade systems change much quicker than building regulations. Fire spread in one key issue of fire safety in facades. But falling parts, smouldering, smoke and secondary openings are issues as well. T2 - The 4th International Symposium on Fire Safety of Facades FSF 2024 CY - Lund, Sweden DA - 10.06.2024 KW - Facade systems KW - Fire testing KW - Assessement method PY - 2024 AN - OPUS4-60250 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hofmann-Böllinghaus, Anja T1 - Waldbrandforschung im EU-Projekt TREEADS N2 - Die Präsentation gibt einen Überblick über die Arbeiten im German Pilot des EU-Projekts TREEADS. Es werden klein-, mittel- und großskalige Versuche an Waldboden mit einheimischer Vegetation durchgeführt. Begleitend werden numerische Untersuchungen durchgeführt, die eine Variation der Parameter, wie Bodenfeuchte, Temperaturen und Wind über die Experimente hinaus erlauben. Die gemessenen Materialparameter dienen als Input für die numerischen Berechnungen. Die numerischen Modelle werden mit den mittel- und großskaligen Experimenten validiert. T2 - Magdeburger-Köthener Brandschutz- und Sicherheitstagung CY - Magdeburg, Germany DA - 14.03.2024 KW - Waldbrand PY - 2024 AN - OPUS4-59897 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Wu, Hongyi T1 - Applying experimental determined kinetic parameters to the simulation of vegetation fire in the Fire Dynamics Simulator N2 - Although intense wildfire research has been done in the US and in Australia, it cannot be transferred directly to the situation in Europe as the local vegetation has a significant influence on the fire spread. The EU-funded project TREEADS and the so-called German pilot within the project are concentrating on wildfire in Europe. Extensive experimental research is done on local vegeta-tion in Germany and the experimental results are used to adjust the Fire Dynam-ics Simulator (FDS) to local vegetation as a fuel in the calculations. The particle model and the boundary fuel model are developed for the simulation of forest fires. Both models require the kinetic input for the dehydration, pyrolysis, and char oxidation process. This three-step simplified model describes the basic fuel combustion kinetic. Most published simulations use the default kinetic input of pine needles from FDS user manual. To adjust the simulation to local vegetation, the corresponding kinetic parame-ters have been experimental investigated. Samples of pine needles, moss and other falling leaves were collected, air dried and grinded into powder. The TG analysis of all these samples were done under different heating rate of 5, 10 and 20K/min. The activation energy and the corresponding pre-exponential factor were calcu-lated. The results show that fire spread depends significantly on the vegetation and comparison with small scale experiments show good agreement using the new kinetic parameters. The new model is applied to a larger scenario and will be compared to the results of large-scale experiments for further validation of the model. T2 - Wood and Fire Safety 2024 CY - Štrbské Pleso, Slovakia DA - 12.05.2023 KW - Simulation KW - Forest KW - FDS KW - Fire Dynamics Simulator KW - Kinetic parameters KW - Vegetation fire PY - 2024 AN - OPUS4-60256 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Wu, Hongyi A1 - Hofmann-Böllinghaus, Anja T1 - TREEADS - Experimente und numerische Simulation zur Brandausbreitung von Vegetationsbränden N2 - Um die Ausbreitungsmechanismen von Vegetationsbränden und besonders bei Bodenbränden besser zu verstehen, wurden die Einflussfaktoren auf die Brandausbreitung näher untersucht. Da die Brandausbreitung auch in starkem Maße von der lokalen Vegetation abhängt, war eine Charakterisierung der lokalen Vegetation und der Bodenverhältnisse wichtig. Die Wetterverhältnisse spielen einerseits im Vorfeld des Brandes durch längere Dürreperioden als auch während des Brandes, z.B. durch den Windeinfluss, zusätzlich eine große Rolle. Durch die numerische Simulation kann eine größere Variation der Einflussgrößen abgebildet werden als durch die zeitlich und finanziell begrenzten experimentellen Möglichkeiten. Für die Berechnungen wird der Fire Dynamic Simulators (FDS) mit dem Paket WFDS verwendet. Dadurch kann mit einem vereinfachten 3-Phasen-Reaktionskinetikmodell, bestehend aus Dehydrierung, Pyrolyse, Kohleoxidation, die Ausbreitung von Vegetationsbränden verschiedener Waldbodenarten untersucht werden. Es wurden dazu 6 typische Pflanzenarten und Bodenproben aus Kiefern-, Buchen und Eichenbeständen ausgewählt. Die gesammelten Waldbodenproben wurden alle hinsichtlich des Wassergehalts, des organischen Gehalts, der Packungsdichte, der Dichte und der statistisch ermittelten Pflanzenartenverteilung charakterisiert. Das kinetische Abbrandverhalten wurde durch Thermogravimetrische Analyse (TGA) untersucht. Alle diese Daten wurden als Eingabeparameter für die Simulation verwendet. Die numerischen Simulationen werden mit Experimenten im kleinen, mittleren und Real-Maßstab validiert. T2 - 70. Jahresfachtagung der Vereinigung zur Förderung des Deutschen Brandschutzes CY - Magdeburg, Germany DA - 06.05.2024 KW - Waldbrand KW - Simulation KW - FDS PY - 2024 AN - OPUS4-60257 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Wu, Hongyi T1 - Experimental investigating flame propagation of vegetation fire in different scales N2 - Since we are facing more extreme weathers, the occurrence of wildfire has also increased accordingly. The EU project TREEADS aims to adopt a holistic forest fire management and an adaptive, collaborative governance approach based on the deployment of a new systemic and technological framework covering all three interconnected fire management stages: prevention & preparedness, detection & response, and restoration & adaptation. As part of the task in the so-called German pilot, numerical simulations are performed to investigate the influencing factors for vegetation fires with fire dynamics simulator (FDS). The characteristics of vegetation are strongly related to the local weather and ecosystem. The investigation of the fire behavior of vegetation must be based on the local vegetation in Germany. Thus, the flame propagation of typical vegetation in Germany (pine needles, oak leaves, European beech leaves etc.) was investigated in small scale and medium scale experiments. These results are used as validation case studies for the further simulations. T2 - NFSD Nordic Fire and Safety Days CY - Lund, Sweden DA - 18.06.2024 KW - Vegetation fire KW - Flame propagation KW - Vegetation in Germany KW - SBI-test KW - Wildfire PY - 2024 UR - https://ri.diva-portal.org/smash/record.jsf?pid=diva2%3A1869356&dswid=6005 AN - OPUS4-60632 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Festag, Sebastian A1 - Esser, Jonas A1 - Maiworm, Björn A1 - Hofmann-Böllinghaus, Anja T1 - Herausforderungen des modernen Holzbaus: Erste statistische Erkenntnisse aus realen Gebäudebränden in Holzbauweise N2 - Hinsichtlich des Brandschutzes zeigt der durch die Bundesregierung geförderte Holzbau Herausforderungen gegenüber Massivbauweisen. Diese spiegeln sich in Erfahrungen von Feuerwehren wider, aber nun auch in statistischen Untersuchungen der Brandschadenstatistik der Vereinigung zur Förderung des deutschen Brandschutzes sowie der Arbeitsgemeinschaft der Leiterinnen und Leiter der Berufsfeuerwehren (AGBF) und des Deutschen Feuerwehrverbands (DFV). Im Zeitraum von 2013 bis 2017 wurden in der vfdb-Brandschadenstatistik Daten zu 5016 Alarmierungen bei Gebäudebränden in Deutschland systematisch mit einem einheitlichen Erfassungsbogen erfasst und seit 2016 „bemerkenswerte Brandeinsätze“ durch einen Evaluierungsbogen zu Maßnahmen des vorbeugenden Brand- und Gefahrenschutzes von AGBF/DFV. Grundlage des vorliegenden Beitrags sind die Auswertung und der Vergleich beider statistischer Datensätze hinsichtlich der Brände in Gebäuden in Holzbauweise. Es zeigt sich, dass der Holzbau mit brandschutztechnischen Herausforderungen verbunden ist. KW - Brandschutz KW - Brandstatistik PY - 2025 DO - https://doi.org/10.1002/bate.202400078 SN - 1437-0999 VL - 2025 IS - 102 SP - 1 EP - 8 PB - Wiley AN - OPUS4-63000 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR ED - Manzello, Samuel L. ED - Hofmann-Böllinghaus, Anja T1 - Special issue on wildland-urban interface (WUI) fires N2 - Special issue on wild-urban interface (WUI) fires with 25 papers in total. Contributed papers came from all across the globe and included Algeria, Australia, Brazil, China, France, Germany, Japan, Poland, Norway, New Zealand, Spain, Sweden, and the United States of America. The global coverage of contributed papers demonstrated the growing nature of the WUI fire problem. KW - Wildfire PY - 2025 UR - https://onlinelibrary.wiley.com/toc/10991018/2025/49/5 SN - 1099-1018 SN - 0308-0501 VL - 49 IS - 5 SP - 507 EP - 846 PB - Wiley CY - New York, NY AN - OPUS4-63992 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Strangfeld, Christoph A1 - Wiehle, Philipp T1 - Closure of "Quantification of moisture content in earth block masonry under natural climatic conditions" N2 - In January 2025, the research paper “Quantification of moisture content in earth block masonry under natural climatic conditions” was published in Construction and Building Materials. The central theme was the moisture monitoring of a masonry wall made of unstabilised earth blocks over a period of around 18 months. The experimental results were compared to WUFI simulations, and the moisture transport in layered wall constructions was eventually studied in WUFI. Prof. Janssen discussed this publication in Construction and Building Materials. He raised concerns about the experiments and modelling of moisture transport. In this closure, the capillary adsorption coefficient was recalculated, and deviations from the initial value were quantified. Sensitivity analyses were conducted in WUFI to evaluate the influence of different water vapour resistances and water adsorption coefficients. The resulting moisture transport was then compared to material moisture profiles measured using 1H NMR relaxometry. Finally, the water adsorption behaviour of different earth materials is discussed in respect to material moisture and corresponding relative humidity. KW - Earth masonry KW - Moisture transport KW - Capillary water absorption KW - Embedded humidity sensors KW - NMR KW - WUFI KW - Material moisture KW - Water vapour diffusion resistance KW - Sustainable building materials PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-637569 DO - https://doi.org/10.1016/j.conbuildmat.2025.142552 SN - 0950-0618 VL - 491 SP - 1 EP - 6 PB - Elsevier Ltd. AN - OPUS4-63756 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Rockel, Daniel A1 - Sanchez Olivares, G. A1 - Calderas, F. A1 - Schartel, Bernhard T1 - It’s not waste, it’s a resource: Utilizing industrial waste fibers/mineral fillers to attain flame retardant biocomposites N2 - Integrating natural fibers derived from local industrial waste streams into thermoplastic starch (TPS) proves to be a promising approach towards sustainable flame retardant biocomposites. Initially, three types of waste fibers from the agave, coconut, and leather industries were evaluated for their flame retardant properties in combination with aluminum trihydroxide (ATH), an environmental friendly flame retardant. Leather fiber (BLF) exhibited the best flame retardant performance and were further investigated along with ATH and varying amounts of bentonite nanoclay to enhance the residual protective layer. The combination of multiple components shows improvement in performance while reducing the total load of filler. The images of the fire residues revealed that a more enclosed surface correlates with a reduction in the peak of heat release rate. Whereas higher amounts of bentonite does not deliver further inprovements, only 1 phr nanoclay in the novel multicomponent system of TPS, ATH, BLF, and bentonite synergistically improved the UL-94 rating from HB to V1. The proposed system brings together the different approaches using a renewable biopolymer, natural waste fibres, and envirnmentally friendly flame retardancy and thus, is striking for its combination of outstanding sustainablity, instant feasability, and sufficient fire performance. KW - Biocomposites KW - Flame retardancy KW - Residue analysis KW - Sustainability KW - Waste streams PY - 2025 DO - https://doi.org/10.1177/08927057241297083 SN - 0892-7057 SN - 1530-7980 VL - 38 IS - 6 SP - 2225 EP - 2252 PB - Sage AN - OPUS4-63431 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Szymoniak, Paulina T1 - Bio-Based Vitrimers: Cracking the Code of Recyclability, Exchange Reactions and Flame Retardancy N2 - Vitrimers are a promising class of sustainable materials that offer an alternative to traditional epoxy thermosets in line with circular economy principles. Built on covalent adaptive networks (CANs), they can rearrange their chemical bonds in response to external stimuli, giving them properties like recyclability, shape-memory, and self-healing. These materials combine the strength of thermosets with the reprocessability of thermoplastics, making them attractive for next-generation applications. This study focuses on a bio-based vitrimer made from glycerol triglycidyl ether (GTE) and a vanillin-derived imine hardener (VA), which reacts through catalyst-free imine metathesis. To better understand the recyclability mechanisms of such systems, especially the dynamic bond exchange, we apply a comprehensive suite of techniques including dielectric spectroscopy, neutron scattering, mechanical analysis, and calorimetry. By linking molecular dynamics with macroscopic performance, the work aims to support the development of vitrimers as practical, recyclable materials. T2 - EPF2025 - European Polymer Congress CY - Groningen, The Netherlands DA - 22.06.2025 KW - Polymer recycling PY - 2025 AN - OPUS4-63859 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hothan, Sascha T1 - Durability of Intumescent Coatings - Experimental investigations and test concepts for a working life of more than 10 years N2 - Intumescent coatings are subjected to ageing effects caused by climatic influences. The established European regulations to assess the durability of intumescent coatings are limited to a working life of 10 years. In the presentation experimental investigations and test concepts to extend the working life to 25 years are shown. In addition, a new in-situ testing method to assess the performance of applied intumescent coatings that have undergone ageing processes is presented. T2 - Annual Meeting of ECCS TC3 CY - Online meeting DA - 25.09.2023 KW - Intumescent coatings KW - Experimental investigations KW - In-situ testing PY - 2023 AN - OPUS4-63979 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Geoerg, Paul A1 - Schumann, J. A1 - Boltes, M. A1 - Holl, S. A1 - Hofmann-Böllinghaus, Anja T1 - The influence of individual impairments on crowd dynamics N2 - Emergency exits as bottlenecks in escape routes are important for designing traffic facilities. Especially the fundamental diagram is a crucial performance criterion for assessment of pedestrians' safety in facilities and an important basis for calculation methods. For this reason, several studies were performed during the last decades which focus on the quantification of movement through bottlenecks. These studies were usually conducted with populations of homogeneous characteristics to reduce influencing variables and for reasons of practicability. Studies which consider heterogeneous characteristics in performance parameters are rarely available. In response and to reduce this lack of data a series of well-controlled large-scale movement studies considering pedestrians with different disabilities was carried out. T2 - Interflam 2019 CY - London, UK DA - 01.07.2019 KW - Evacuation PY - 2019 VL - 2019 SP - 775 EP - 791 PB - Interscience CY - London, UK AN - OPUS4-48647 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Geoerg, Paul A1 - Schumann, J. A1 - Holl, S. A1 - Hofmann-Böllinghaus, Anja T1 - The Influence of Wheelchair Users on Movement in a Bottleneck and a Corridor N2 - Emergency exits as bottlenecks in escape routes are important for designing traffic facilities. Particularly, the capacity estimation is a crucial performance criterion for assessment of pedestrians' safety in built environments. For this reason, several studies were performed during the last decades which focus on the quantification of movement through corridors and bottlenecks. These studies were usually conducted with populations of homogeneous characteristics to reduce influencing variables and for reasons of practicability. Studies which consider heterogeneous characteristics in performance parameters are rarely available. In response and to reduce this lack of data a series of well-controlled large-scale movement studies considering pedestrians using different types of wheelchairs was carried out. As a result it is shown that the empirical relations are strongly affected by the presence of participants with visible disabilities (such as wheelchair users). We observed an adaption of the overall movement speeds to the movement speeds of participants using a wheelchair, even for low densities and free flow scenarios. Flow and movement speed are in a complex relation and do not depend on density only. In our studies, the concept of specific flow fits for the nondisabled subpopulation but it is not valid for scenario considering wheelchair users in the population. KW - Evacuation PY - 2019 DO - https://doi.org/10.1155/2019/9717208 SN - 0197-6729 SP - Article ID 9717208-1 EP - 17 PB - Wiley, Hindawi AN - OPUS4-48639 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hofmann-Böllinghaus, Anja A1 - Webb, A. T1 - Changes in façade regulations N2 - Recent facade fires worldwide have driven change in regulations for façade fire safety in different parts of the world. The Grenfell Tower fire 2017 in London triggered a thorough investigation of many aspects of the fire. One investigation was about the UK building regulations from Dame Judith Hackett 1,2. This investigation compares the UK with the situation other parts of the world. T2 - Interflam 2019 CY - London, UK DA - 01.07.2019 KW - Facade KW - Regulations KW - Australia KW - UK KW - Germany PY - 2019 SP - 183 EP - 197 PB - Interscience CY - London AN - OPUS4-48426 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hofmann-Böllinghaus, Anja A1 - Boström, L. A1 - Anderson, J. A1 - Chiva, R. A1 - Guillaume, E. A1 - Colwell, S. A1 - Toth, P. T1 - European approach to assess the fire performance of façades N2 - Several attempts have been made in the past to develop a European harmonized testing and assessment method for façades before the European commission decided to publish a call for tender on the topic. A project consortium from five countries (Sweden, UK, France, Germany and Hungary) applied to the call for tender and was contracted to develop a European approach to assess the fire performance of façades. 24 sub-contractors and 14 stakeholder entities were part of the project. The objective of the European project was to address a request from the Standing Committee of Construction (SCC) to provide EC Member States regulators with a means to regulate the fire performance of façade systems based on a European approach agreed by SCC. In addressing this objective, the project team was asked to consider a number of issues which are presented and discussed. T2 - Interflam 2019 CY - London, UK DA - 01.07.2019 KW - Facade KW - European KW - Fire scenario KW - Testing PY - 2019 SP - 213 EP - 227 PB - Interscience AN - OPUS4-48428 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Klippel, Andrea A1 - Hofmann-Böllinghaus, Anja T1 - Quantitative risk analysis and numerical investigation to determine critical fire scenarios in the environment of handicapped people N2 - Crisis management, particularly the evacuation of handicapped People during a fire scenario presents a highly demanding challenge for nursing staff and rescue forces on site. The German research Project SiME is an interdisciplinary cooperation of university and non-university research institutions as well as medium-sized companies, which work together to develop strategies to manage such critical scenarios. In the SiME project, which is funded by the German Federal Ministry of Education and Research, evacuation characteristics of pedestrians with physical, mental or age-related disabilities are investigated to fit consisting numerical evacuation models with data. One of the major tasks of the OvGU was to set up a database of scenarios related to fire, explosion or substance releases in the working and living environment of handicapped people. Therefore, more than 463 fire Events occurring over the last decade in Germany were documented in this database and categorized by a suitable assignment of characteristics e.g. location of fire, ignition source, number of fatalities and injured. The evaluated data were the basis for carrying out a quantitative risk analysis. Thus event trees were set up for different integrative infrastructures with which occurrence probabilities for different scenarios could be calculated for each path. The extent of damage, as a quantity describing the impact, was assumed to be personal injury or death or serious injury. By a risk assessment critical Scenarios could be derived from the risk analysis. T2 - Interflam 2019 CY - London, UK DA - 1.07.2019 KW - Evacuation PY - 2019 VL - 2019 SP - 795 EP - 806 PB - Interscience CY - London, UK AN - OPUS4-48649 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hofmann-Böllinghaus, Anja T1 - European Approach to assess the fire Performance of façades N2 - In this study included: The consideration of a façade kit as a construction product The consideration of a façade as a part of a specific building. In some national regulations this would mean that detailing such as window openings may also need to be considered. Fire scenario identification for each of the Member States that regulate for the fire performance of the façade system based on alternative assessment methods. T2 - Interflam 2019 CY - London, UK DA - 01.07.2019 KW - Europe PY - 2019 AN - OPUS4-48642 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Klippel, Andrea A1 - Hofmann-Böllinghaus, Anja T1 - Experimental Analysis of Fire Behaviour in Pine Forests and Agricultural Fields Large Scale Tests conducted within the TREEADS Project N2 - In two large-scale tests fire spread mechanisms in vegetation ground fires were studied in a pine forest and a crop field. Both fires were ignited with a drip torch using a gasoline-diesel mix. The tests were part of the European TREEADS project, specifically in the research work from the German Pilot focusing on Saxony-Anhalt and Brandenburg. These regions are known for dry, sandy soil, with pine trees covering approximately 73% of forested areas in Brandenburg and 48% in Saxony-Anhalt. The results of both experiments make a substantial contribution to optimizing extinguishing methods and strategies and enhancing a continued wildfire research in Germany. The test areas included a 16 x 22 m plot in a Saxony-Anhalt pine forest and a 20 x 100 m plot on a crop field, with fires ignited along a line using a drip torch at both locations. Fire spread was monitored with video and IR cameras mounted on a drone. In the pine forest, 96 thermocouples and gas sensors were attached to trees and a mobile FTIR spectrometer was used for real-time gas measurements. A protective strip was created around the test area using a soil tiller and fire-retardant foam to prevent uncontrolled fire spread. The experiment showed a consistent temperature rise as the fire was ignited and spread. Thermocouple data captured detailed thermal dynamics, while tree-mounted gas sensors recorded significant fluctuations in combustible gases. Real-time gas spectra from the FTIR spectrometer enabled precise smoke analysis. Conducted in stable weather - 23°C, light wind, low soil moisture—this setup improved reproducibility, with a weather station monitoring temperature, humidity and wind conditions to assess fire-environment interactions. After ignition process the fire showed a slow spread and distinct combustion phases. Smouldering was more pronounced in areas with grasses and deadwood, highlighting vegetation-specific burn patterns critical to wildfire research. The experiment showed numerous smouldering and burning spots, with flames igniting and extinguishing repeatedly. However, flame height did not exceed half a meter. Due to substantial smoke production, visibility in the test field was limited and team members wore respirators to collect specific smoke gases such as benzene and formaldehyde for analysis. Field measurements showed flame temperatures exceeding 500°C. Toxic smoke gas concentrations of up to 238 ppm CO were measured, although precise gas capture appeared challenging due to wind turbulence. The second large-scale area in Nauen, a cut wheat field (stubble height approx. 30 cm) was burned, with fire spreading across approximately 700 m². A 20 m ignition line directed flames with the wind. Fire spread was observed using drones equipped with IR cameras. Experiments demonstrated how unpredictable and challenging it is to measure large outdoor fires. To enable a comprehensive theoretical and numerical description of fire dynamics in wildfires, it is essential to conduct further large-scale experiments. T2 - Interflam 2025, 16th International Fire Science and Engineering Conference CY - London, United Kingdom DA - 30.06.2025 KW - Wildfire KW - Large scale tests PY - 2025 AN - OPUS4-63923 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CHAP A1 - Hofmann-Böllinghaus, Anja ED - Vogdt, F. U. T1 - Brandschutz N2 - Grundlagen des vorbeugenden baulichen Brandschutzes KW - Brandprüfungen KW - Bauvorschriften PY - 2022 SN - 978-3-8348-2189-8 SP - 199 EP - 220 PB - Springer ET - 1 AN - OPUS4-54317 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CHAP A1 - Hofmann-Böllinghaus, Anja ED - Fouad, N. A. T1 - Brandsicherheit von Bussen N2 - Grundsätzlich lässt sich sagen, dass Busbrände relativ häufig auftreten, auch wenn sich das im öffentlichen Bewusstsein nicht unbedingt widerspiegelt. In Deutschland gibt es keine einheitliche Brandstatistik, nach einer eigenen Internetrecherche brennt im Schnitt aber etwa an jedem zweiten Tag ein Bus in Deutschland. Auch eine interne Umfrage eines Verbands von Busbetreibern bestätigte die Häufigkeit von Bränden: Ungefähr 1 Prozent der Busse hatte im Jahr einen Brandfall – wobei hier auch kleinere Ereignisse mitgezählt wurden. Die britische Statistik bestätigt diese Zahlen. Sie führt für die letzten 10 Jahre ca. 11900 Brände pro Jahr in Fahrzeugen, davon ca. 315 pro Jahr in Bussen auf. Brände in Bussen sind für die Passagiere eine große Gefährdung, da sie sich meist sehr schnell ausbreiten. Zwei schwere Brände ereigneten sich in Deutschland 2008 und 2017. KW - Bussicherheit KW - Vorschriften KW - Brandprüfungen PY - 2021 SN - 978-3-433-03295-4 VL - 2021 SP - 386 EP - 398 PB - Ernst und Sohn CY - Berlin AN - OPUS4-53090 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Manzello, Samuel L. A1 - Hofmann-Böllinghaus, Anja T1 - Editorial on special issue on wildland–urban interface (WUI) fires N2 - Research and standardization in the field of wildland fires that spread into urban areas, known as wildland–urban interface (WUI) fires, are of paramount importance globally. Recent WUI fires in Chile, Greece, Japan, and the United States of America states of California and Hawaii, following many other WUI fire disasters, have demonstrated the complex nature of this globally important problem. For these reasons, the editor in chief of Fire and Materials, Stephen Grayson, invited Samuel L. Manzello and Anja Hofmann to develop a special issue on WUI fires. In support of this effort, an open call was posted on the Fire and Materials website, soliciting papers on the following topics: • Pre- and post-fire data to understand fire spread and ignition of materials in WUI communities. • Firebrand generation from materials. • Ignition of both vegetative and human-made fuels from WUI fire exposures of direct flame contact, radiant heat, and firebrands. • Human behavior in WUI fires. • Physical modeling studies of WUI fire behavior and structure ignition. • Structure ignition mitigation strategies. • New material development to harden structures to WUI fire exposures. KW - Editorial KW - Wildfire PY - 2025 DO - https://doi.org/10.1002/fam.3308 SN - 1099-1018 SN - 0308-0501 VL - 49 IS - 5 SP - 509 EP - 511 PB - Wiley CY - New York, NY AN - OPUS4-63920 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CHAP A1 - Hofmann-Böllinghaus, Anja A1 - Brandt, J. ED - Troitzsch, J. ED - Antonatus, E. T1 - Motor Vehicles N2 - The amount of plastic and synthetic materials is still growing in all sectors of everyday life. In the automotive industry, plastic materials are now widely used in vehicles because of their excellent mechanical properties and their light weight combined with low production costs. However, plastic materials are flammable and can generate toxic smoke gases which can endanger passengers’ lives in the event of fire. KW - Transport KW - Bus fire KW - Safety PY - 2021 SN - 978-1-56990-762-7 VL - 2021 SP - 537 PB - Hanser CY - München ET - 4 AN - OPUS4-53094 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Gnutzmann, Tanja T1 - Brandschutz für Kulturgut: Das Projekt BRAWA N2 - Brände zerstören immer wieder wichtige Kulturgüter und gefährden nationales Kulturerbe. Das Projekt BRAWA erarbeitet neue Strategien und innovative Technologien, um die Brandsicherheit historischer Gebäude zu erhöhen. Dabei basiert das Konzept auf der Vernetzung von Sensoren, die bereits beim Auftreten bestimmter Gase in der Frühphase der Brandentstehung Alarm auslösen. Durch ein neuartiges Helferkonzept soll eine frühe Branderkennung und -bekämpfung ermöglicht werden. T2 - BMBF Innovationsforum "Zivile Sicherheit" 2022 CY - Berlin, Germany DA - 03.05.2022 KW - Brandschutz KW - Kulturgut KW - Historische Gebäude KW - Branddetektion KW - Sensornetzwerk PY - 2022 AN - OPUS4-54828 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hofmann-Böllinghaus, Anja A1 - Anderson, J. T1 - Editorial: Special issue facades N2 - Facade fires are of growing concern worldwide. Severe facade fires in different parts of the world as well as activities in many countries regarding the testing of facades show the urgency of the fire safety challenges in façade fires. The need for knowledge and a wide Archive of work in this area has become evident after recent incidents which involved extensive facade fires. These include the tragic fires in Dubai and Grenfell Tower in 2017 in the United Kingdom. In many cases, the widespread live news coverage of the events and size of These fires has emphasized the need for progress in the understanding of the processes involved in these fires and put pressure upon the fire safety engineering community to find effective solutions. KW - Facade fire PY - 2021 DO - https://doi.org/10.1002/fam.3001 SN - 0308-0501 SN - 1099-1018 VL - 45(5) IS - Special issue: Facade fire safety SP - 585 PB - Wiley CY - Oxford AN - OPUS4-53093 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Sunder, S. A1 - Jauregui Rozo, Maria A1 - Inasu, S. A1 - Meinel, Dietmar A1 - Schartel, Bernhard A1 - Ruckdäschel, H. T1 - Effect of Ammonium Polyphosphate/Silicate Content on the Postfire Mechanics of Epoxy Glass-Fiber Composites Using Facile Chocolate Bar-Inspired Structures N2 - This study investigates the postfire mechanical properties of epoxy glass-fiber reinforced composites (EP GFRCs) using increasing concentrations of ammonium polyphosphate (APP) and inorganic silicate (InSi) to modify the char and fire residue. A facile chocolate bar-inspired structure was introduced for fire exposure and subsequent flexural testing of the GFRCs. The resin matrix used here was a diglycidyl ether of bisphenol-A (DGEBA) resin, cured with dicyandiamide (DICY), and accelerated by Urone. The microstructures of the degraded composites after three-point bending tests, were evaluated using scanning electron microscopy (SEM) and x-ray computed tomography (XCT) imaging. A previous study showed that increasing the APP and InSi content significantly enhanced flame retardancy, via improved char formation under fire conditions. However, flexural properties and fire resistance were adversely affected after fire exposure, highlighting a trade-off effect. Fiber breakage and delamination of the composites increased upon failure with increasing APP + InSi content in the composite due to unconsolidated char. The experimental values for the postfire flexural mechanics were in good agreement with the two-layer model proposed in literature. This paper presents a preliminary basis for postfire mechanical testing of epoxy composites for use in fire-safe structures, using a combination of standardized testing norms. KW - Flame retardants KW - Post-fire KW - Epoxy KW - Gass fiber composites KW - Prepregs PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-627176 DO - https://doi.org/10.1002/fam.3280 SN - 0308-0501 SN - 1099-1018 VL - 49 IS - 3 SP - 329 EP - 346 PB - Wiley AN - OPUS4-62717 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bibinger, J. A1 - Eibl, S. A1 - Gudladt, H.-J. A1 - Schartel, Bernhard A1 - Höfer, P. T1 - Pushing the limits of thermal resistance in nanocomposites: A comparative study of carbon black and nanotube modifications N2 - Enhancing the thermal resistance of carbon fiber-reinforced polymers (CFRPs) with flame retardants or coatings often leads to increased weight and reduced mechanical integrity. To address these challenges, this study introduces an innovative approach for developing nanocomposites using carbon-based nanoparticles, while preserving the structural lightweight properties. For this, carbon black particles (CBPs) up to 10% and carbon nanotubes (CNTs) up to 1.5% were incorporated into the RTM6/G939 composite material. The obtained samples were then analyzed for their properties and heat resistance under one-sided thermal loading at a heat flux of 50 kW/m2. Results demonstrate that integrating these particles improves heat conduction without compromising the material’s inherent advantages. As a result, thermo-induced damage and the resulting loss of mechanical strength are delayed by 17% with CBPs and 7% with CNTs compared to the unmodified material. Thereby, the thermal behavior can be accurately modeled by a straightforward approach, using calibrated, effective measurements of the nanoparticles in the polymer matrix rather than relying on theoretical assumptions. This approach thus provides a promising methode to characterize and improve thermal resistance without significant trade-offs. KW - Nanomaterial KW - Cabon fiber-reinforced polymer (CFRP) KW - Carbon black (CB) KW - Carbon nanotube (CNT) KW - Improving heat conduction KW - Prediction thermal properties PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-628632 DO - https://doi.org/10.3390/nano15070546 SN - 2079-4991 VL - 15 IS - 7 SP - 1 EP - 23 PB - MDPI CY - Basel AN - OPUS4-62863 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Tabaka, Weronika A1 - Schartel, Bernhard T1 - Less is More: Optimised Fire Performance in Glass Fibre-reinforced Polybutylene Terephthalate Laminates with Concentrated Flame Retardant Top Layer N2 - To achieve optimum fire performance while maintaining mechanical integrity, flame retardants (FR) were strategically concentrated in the surface layer of a two-layer glass fibre-reinforced polybutylene terephthalate (PBT) laminate structure. Three potentially synergistic FR systems were selected to improve the fire performance of glass fibre-reinforced PBT: boehmite (AlOOH) with melamine polyzinc phosphate (MPZnP), aluminium diethyl phosphinates (AlPi) with melamine cyanurate (MC), and expandable graphite (EG) with melamine polyphosphate (MPP). Limited Oxygen Index (LOI) and UL-94 testing highlighted the influence of laminate architecture on flammability. The cone calorimeter results showed that increasing the FR concentration in the top layer significantly reduced both the peak heat release rate (PHRR) and the maximum average rate of heat emission (MARHE), with improvements depending on the specific FR system used. The laminate L-PBT/GF/AlOOH/MPZnP with a 2:2 thickness ratio showed outstanding performance, achieving a 45 % reduction in MARHE compared to composites with uniform FR distribution. This result showcases the superior thermal barrier properties and synergistic behaviour of AlOOH and MPZnP. The fire performance of laminates containing AlPi and MC was strongly influenced by the distribution and concentration of AlPi/MC. The EG/MPP system was found to be highly effective, forming a protective intumescent layer that significantly reduced both HRR and MARHE, demonstrating the effectiveness of strategically concentrating FR in the top layer. KW - Glass fibres KW - PBT KW - Flame retardants KW - Composites KW - Laminates KW - Fire behaviour KW - Flammability PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-626381 DO - https://doi.org/10.1016/j.jcomc.2025.100577 SN - 2666-6820 VL - 16 SP - 1 EP - 15 PB - Elsevier B.V. AN - OPUS4-62638 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wagner, Jan A1 - Dudziak, Mateusz A1 - Falkenhagen, Jana A1 - Rockel, Daniel A1 - Reimann, H.-A A1 - Schartel, Bernhard T1 - This is the way: An evidence based route to phytic-acid–based flame retardant poly(lactide acid) N2 - A systematic sequence of materials was investigated to develop phytic-acid (Phyt)–based flame retarded poly (lactide acid) (PLA), while factoring in molecular weight (MW), crystallinity and mechanical properties. Synergistic approaches were developed based on combinations with lignin and expandable graphite (EG), as well as by applying different Phyt salts of melamine (Mel), piperazine (Pip), and arginine (Arg). Compounds were twin screw extruded, injection molded, hot pressed and investigated with thermal analysis, size exclusion chromatography, infrared spectroscopy, tensile testing, limited oxygen index (LOI), UL 94, cone calorimeter, and scanning electron microscope. 16.7 wt.% flame retardant (FR) slightly enhances crystallization while MW remains unchanged in PLA Phyt Arg and PLA Phyt Mel. LOI was improved to 43.7 vol.% for PLA Phyt Arg, UL 94 V0 achieved for PLA Phyt Pip. Cone calorimeter results show total heat evolved reduced by 14 %, maximum average rate of heat emission 43 % lower, and peak heat release rate reduced by 50 % for PLA Phyt Mel. Phyt Mel combined with EG increased the char yield of PLA to 20 wt.% and 15.5 wt.% at 600 and 900 ◦C, respectively. Phyt is exploited to enhance char yield, stabilize the intumescent char, and lower the apparent effective heat of combustion. The combination of Phyt Mel and EG was proposed as an efficient FR for PLA via an evidence based developing route. KW - Polylactide acid KW - Intumescent flame retardant KW - Phosphorous flame retardant KW - Phytic acid KW - Expandable graphite KW - Melamine PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-626395 DO - https://doi.org/10.1016/j.polymdegradstab.2025.111242 SN - 1873-2321 SN - 0141-3910 VL - 234 SP - 1 EP - 14 PB - Elsevier Ltd. AN - OPUS4-62639 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hupp, Vitus A1 - Schartel, Bernhard A1 - Flothmeier, K. A1 - Hartwig, A. T1 - Flame Retarded Adhesive Tapes and Their Influence on the Fire Behavior of Bonded Parts N2 - Pressure-sensitive adhesive tapes are used in automotives, railway vehicles and construction, where flame retardancy is of major importance. This is why industrial applicants often buy, and industrial tape manufacturers often produce, flame-retardant adhesive tapes, advertised for their good flammability characteristics. Yet, how flame-retardant tapes influence the fire behavior of bonded materials is a rather open question. To investigate this issue, three different substrates were bonded, using eight double-sided adhesive tapes containing two different carriers and two different flame retardants. The bonded substrates were compared to their monolithic counterparts in terms of flammability, fire behavior and fire stability. The fire behavior of adhesive tape bonded materials differed significantly from the monolithic substrates. The usage of different adhesive tapes let to different burning behavior of the bonded materials mainly due to different carrier systems. In contrast, the implementation of flame retardant into the adhesive had rather minor or no effect on the burning behavior of the bonded substrates despite their positive effect on the flammability of the free-standing tape. The carrier changed the HRR curve in the cone calorimeter and was able to both, reduce and increase fire hazards. Using the carrier with the better fire performance can lower the fire growth rate by 20%, the peak of heat release rate by 27%, and the maximum average rate of heat emission by 30% in cone calorimeter tests. Overall, the fire behavior of bonded materials is a complex interaction between substrate, adhesive, and carrier, and depends on the fire scenario the materials are exposed to. KW - Pressure-sensitive adhesive tapes KW - Bonded materials KW - Fire behaviour KW - Fire resistance KW - Flame retardant KW - Cone calorimeter PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-626006 DO - https://doi.org/10.1007/s10694-024-01637-2 SN - 1572-8099 SN - 0015-2684 VL - 61 IS - 2 SP - 729 EP - 749 PB - Springer Nature AN - OPUS4-62600 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schartel, Bernhard T1 - 1 + 1 ≠ 2 – Laminate Materials Meet Flame Retardancy N2 - Main message: Fire tests monitor the specific response of defined test specimens but are used to assess materials’ fire risks. The weakness of this simplification becomes obvious for laminate materials. The talk delivers inspiring food for thought in discussing the fire behaviour of laminates. The fire behaviour must not be expected to be a simple superposition. The design of laminate can generate fire risks as well as give birth to flame retardancy. Introduction Bench-scale fire testing monitors the reaction-to-fire response of well-defined test specimens in certain fire scenarios. Results are often discussed as kind of material properties; indeed, the fire risks of materials are assessed. The weakness of this simplifying concept becomes obvious when it comes to investigating material systems such as all kind of laminate materials. The talk delivers inspiring food for thought sketching the complex and sometimes surprising fire behaviour of laminates. Experimental The polymer analysis, thermal analysis, and investigation of fire behaviour were performed according to the state of the art, mostly in accordance with the ISO standards. We fulfil high quality standards in terms of maintenance, calibration, participation in round robins, and so on. Work steps such as compounding of the materials or injection moulding of test specimen were outsourced or done with partners that have the relevant core competence. The presentation is based on the conclusions and concrete results of projects performed in the group of the author, whose experimental is described in the corresponding scientific papers in detail.[1-3] Results and Discussion Examples show that the fire behaviour of laminates must not be expected to be a simple superposition of the fire behaviour of the individual materials. Indeed, laminate effects can be crucial and influence the flammability relevantly. The design of the laminate can generate fire risks as well as give birth to synergistic flame retardancy. Veneered wood, lacquered products, or foil laminated materials are sketched to illustrate the topic with its potential and challenges. Glued samples consisting of two plates of the same material are discussed to generate some basic understanding as well as to investigate the fire behaviour of glued materials. The impact of the glue line on the burning behaviour of different polymeric materials such as bisphenol A polycarbonate, polymethylmethacrylate, and wood differs remarkably.[2] Further, the role of the glue including but not limited to using flame retarded glues is scrutinized. Making the best out of this understanding we have proposed to concentrate flame retardancy in the top layer.[1, 3] To achieve optimum flame-retardant effect or flame retardancy without disturbing the property profile of the core, flame retardants are strategically concentrated in the surface layer of thermoplastic materials with a laminate structure. Several systems increasing the charring and forming a residual protective layer are identified showing a synergistic effect compared to homogenously flame retarded test specimen. This research presented a promising solution for reducing the use of flame retardants without sacrificing fire performance or mechanical properties, offering significant advantages for industrial applications. T2 - 20th European Meeting on Fire Retardant Polymeric Materials (FRPM2025) CY - Madrid, Spain DA - 03.06.2025 KW - Fire behaviour of laminates KW - Flame retardancy by laminate design PY - 2025 AN - OPUS4-63394 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schartel, Bernhard T1 - Fire Retardancy Featuring Sustainability: Food for Thought between Fake Fiction and Future N2 - MAIN MESSAGE: Sustainability, or in other words, exploiting environmental conservation for the economic welfare and prosperity for all, would revolutionise the plastics industry were it to become predominant practice as a linear, fossil-fuel–based economy is switched to a carbon circular economy. Food for though is given by dint of a critical overview of the current trends in sustainable flame-retardant polymeric materials. STARTING POINT AND INTRODUCTION: Transforming the plastics industry into a carbon circular economy over the next 30 years requires an immediate revolution entailing the development of cutting-edge materials and the planning of future industrial production plants. Hence, the innovative field of flame-retardant polymeric materials for electrical engineering, construction, or materials used in transportation should lend its strength to drive this challenge. Visionary solutions are proposed to inspire us, while the implementation of economically feasible concepts can take us forward into the future. A critical and structured overview of current trends towards sustainable, flame-retardant polymeric materials is presented, using examples from the literature and by sketching our own projects performed in recent years. RESULTS AND DISCUSSION: This overview of current trends towards producing sustainable, flame-retardant polymeric materials is presented, selecting outstanding and representative examples from the literature and sketching main points of our own projects performed in this field in recent years. The examples are structured along a common theme leading from the use of old and new natural materials with some intrinsic flame retardancy, via flame-retardant biopolymers and biocomposites, to using renewable sources for flame retardants with the objective of exploiting natural sources available as industrial waste streams. Natural flame retardants and adjuvants are highlighted, although the status of most may be assessed as merely motivating our vision. However, some of these visionary approaches such as discussing sustainable flame retardants for poly(limonene carbonate), a polymer synthesised from renewable waste and CO2, or wastewater phosphorus enriched micro algae as a sustainable flame retardant in polylactide are rather innovative when achieving a surprising high technological readiness level or providing a comprehensive solution for several urgent demands at once. Further, there are natural material streams finding their way into polymer mass production as fillers, adjuvants, polymers, or renewable educt sources. Natural substances originating from industrial waste streams open the door to sustainable solutions, because they are often available at low cost and avoid competition for land with farming or virgin forests. Aside from this main topic, remarks will address the recycling of flame-retarded polymeric materials; flame retardant vitrimers are mentioned as potential materials for recyclable thermosets. At the end of the day, only convincing property profiles will prevail both for exploiting renewable sources and circular design, including cost effectiveness, sufficient availability, consistent quality, processibility, mechanical properties, and flame retardancy. However, sustainability must not be merely tolerated as an additional demand, but should instead be recognized as a solution, because sustainability aspires to ensure our economic welfare now and in the future. T2 - Interflam 2025 CY - Royal Holloway, Egham, UK DA - 30.06.2025 KW - Biocomposites KW - Sustainability KW - Renewable KW - Bio wastefibres KW - Circular economy KW - Phosphorus flame retardants PY - 2025 AN - OPUS4-63671 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Jauregui Rozo, Maria A1 - Sunder, S. A1 - Inasu, S. A1 - Meinel, Dietmar A1 - Ruckdäschel, H. A1 - Schartel, Bernhard T1 - Weaving Through Fire and Force: Fire Behavior and Fire Stability of Unidirectional, Bidirectional, and Woven Roving Glass-Fiber Composites N2 - This study systematically investigates the transfer of flame retardants (FRs) from epoxy resins to composites. The flame-retardant composites are formulated using bisphenol A diglycidyl ether as the resin and dicyandiamide as the hardener, reinforced with glass fibers (GFs) using various textile architectures: unidirectional (UD), bidirectional (BD), and woven rovings (WR). These composites are evaluated using bench-scale fire stability tests and cone calorimeter experiments to assess critical parameters, including the temperature at failure, time to failure, and fire behavior. Among the tested configurations, UD-GFs demonstrate superior flame retardancy, fire stability, flammability, and mechanical performance, attributed to their higher residue yield, forming a more efficient protective char layer. However, the addition of FRs is limited by their impact on the material's mechanical properties. When the FR content increases to 30 and 50 wt.% of the resin, the composites exhibit a decrease in mechanical performance, adversely affecting both time to failure and temperature at failure. While adding FRs reduces the risk of fire propagation, it does not substantially enhance fire stability or mechanical performance. KW - Fire Resistance KW - Fiber-Reinforced Polymer Composites KW - Fire Stability KW - Glass Fibers KW - Fire Behavior PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-631220 SN - 1438-7492 SN - 1439-2054 VL - 310 IS - 5 SP - 2400432 PB - Wiley VHC-Verlag AN - OPUS4-63122 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schartel, Bernhard T1 - Fire Retardancy Featuring Sustainability: Food for Thought between Fake Fiction and Future N2 - Sustainability, or in other words, exploiting resources under the terms of environmental conservation for the economic welfare and prosperity continuously over time, would revolutionise the plastics industry were it to become predominant practice as a linear, fossil-fuel–based economy is switched to a carbon circular economy. Food for though is given by dint of a critical overview of the current trends and mainly by sketching our own key projects performed in the field of sustainable flame-retardant polymeric materials in the recent years. T2 - Interflam 2025 CY - London, United Kingdom DA - 30.06.2025 KW - Biocomposites KW - Sustainability KW - Renewable KW - Bio wastefibres KW - Fire Behavior PY - 2025 VL - 1 SP - 187 EP - 190 PB - Interscience Communications Ltd AN - OPUS4-63681 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Dey, R. A1 - Dudziak, Mateusz A1 - Prescher, A. A1 - Kreitsmann, T. A1 - Zhang, K. A1 - Posten, C. A1 - Thomson, C. A1 - Schartel, Bernhard A1 - Ullrich, M. S. A1 - Thomson, L. T1 - Sustainable Flame-Retardant Poly Lactic AcidBiocomposites Reinforced with Polyphosphate-EnrichedMicroalgae: Unlocking the Potential of Hyper-Compensation N2 - This study examines the dual benefits of microalgae cultivation for wastewatertreatment and the enhancement of polylactic acid-based biocomposites. UsingDesmodesmus sp. in a photobioreactor, both batch and continuous operationsachieve total nitrogen (TN) and total phosphorus (TP) removal rates of up to99.9%, maintaining TN and TP levels below 0.02 mg L−1 in the effluent, aligningwith European discharge standards. Continuous cultivation increases biomassproductivity from 0.102 to 0.43 g L−1 day−1 , a 322% improvement over batchoperations. Nutrient starvation followed by reintroduction to nutrient-richwastewater induces hyper-compensation luxury uptake, with P-enrichedcells accumulating 1.33% intracellular P within six hours — 21% higherthan natural accumulation. The results reveal that luxury phosphorus uptakein microalgae follows a triphasic system of uptake and storage, challengingthe previously suggested biphasic model. When incorporated into Poly lacticacid (PLA), the biomass enhances versatility, offering potential replacementof inorganic P in industrial applications, particularly flame retardants.Pyrolysis and cone calorimetry confirm the thermal and fire-retardantbenefits, with a 20% reduction in peak heat release rate and increased charyield. This work highlights microalgae’s role in sustainable biocomposites,supporting wastewater treatment, nutrient recovery, and CO2 sequestration. KW - biocomposites KW - biopolymers KW - Flame-retardant KW - Hyper compensation KW - Phycoremediation KW - Wastewater treatment PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-640408 DO - https://doi.org/10.1002/adsu.202500251 SN - 2366-7486 VL - 9 IS - 8 SP - 1 EP - 11 PB - Wiley VHC-Verlag AN - OPUS4-64040 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Wagner, Jan T1 - This is the Way: An Evidence Based Route to Phytic-acid-based Flame Retardant Poly(lactide acid) N2 - Main message: This study provides an evidence-based route to flame retard poly (lactide acid) (PLA) with phytic acid (Phyt)-based flame retardants (FR). Phyt was prepared with lignin (Lig) and expandable graphite (EG). Three amine salts (arginine (Arg), piperazine (Pip), melamine (Mel)) were also synthesized with Phyt. Findings include UL 94 V0 classification, limited oxygen index (LOI) = 43.7 vol% and reduced total heat released (THR), while molecular weight (MW) was not affected. Combinations lead to the most effective FR. Introduction: As demand for biobased polymers increases, biobased FRs remain scarce in the market. With 28 wt.% P, Phyt is promising to be a biobased FR, but Phyt efficiency as a FR needs to be improved. [1] Furthermore, as a strong acid, it esterifies and hydrolysis PLAs backbone. With the combinations proposed in this study, processability and MW in PLA compounds were untouched, while FR performance of Phyt was enhanced. Experimental: Compounds analyzed in this study were: PLA, PLA Lig, PLA EG, PLA PhytLig, PLA PhytEG, PLA Mel, PLA PhytArg, PLA PhytPip, PLA PhytMel, PLA PhytMel Lig and PLA PhytMel EG. Addition of Phyt based FR was 16.7 wt.%, Lig and EG 10wt.%. Compounds were processed with twin screw extrusion, injection molding and hot press. Analysis was done with size exclusion tomography, differential scanning calorimetry (DSC), tensile strength, cone calorimeter, UL 94, LOI and thermogravimetry analysis (TGA) combined with Fourier transformation infrared spectroscopy (FTIR). Residues were analyzed with scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX). Results and Discussion: To synthesize the FR, Lig and Phyt (solved in water) were mixed and dried. A solid material formed, which was grinded and then compounded with PLA. The same was done with EG. Phyt + Arg/Pip/Mel FR materials were each titrated to a pH of ~4.5, since this pH is known to be least harmful for the PLA backbone. For PhytMel a salt precipitated. PhytPip and PhytArg were dried and a resin-like structure was obtained, which was grinded to a powder. The molar mass distribution of PLA PhytArg (10,000 g/mol – 600,000 g/mol) is similar to PLAs ranging from 15,000 g/mol – 600,000 g/mol. MW distribution from highest to lowest was PLA > PLA PhytArg > PLA PhytMel > PLA PhytMel EG > PLA PhytMel Lig > PLA PhytEG > PLA PhytLig > PLA PhytPip. The reaction between Phyt and Arg/Mel prevents MW decomposition of PLA through a reaction of P acid and NH2 groups. Tensile strength declined to 35.9 MPA for PLA PhytMel and 32.1 MPA for PLA PhytArg, compared to 51.4 MPA for PLA. DSC analysis revealed TG was not affected for the FR compounds: Phyt Lig/EG/Arg/Mel, compared to PLA. PLA PhytMel crystallinity 𝐾∆𝐻𝑐𝑐𝑐𝑐 was 30%, PLA PhytArg crystallinity was 50%, compared to PLA 𝐾∆𝐻𝑐𝑐 was 46%. Melting peaks were not affected in PLA Phyt Arg/Mel. Flammability investigations lead to results of LOI 25.8 vol%/ UL 94 V2 classification in PLA, PLA PhytArg LOI 43.7 vol%/ UL 94 V2, due to strong dripping as a cooling mode of action. [2] PLA PhytMel burned with intumescent char and LOI 38.2 vol%/ UL 94 V2 was measured. Due to strong melt dripping, PLA PhytPip reached UL 94 V0. TGA revealed increased residue for all FR compounds. When materials were combined in PLA PhytMel EG residue was maximized to 19.9 wt.% (600°C, 𝑁𝑁2 atmosphere). FTIR analysis revealed PO and PH stretching vibrations, indicating radical scavenging. Cone calorimeter investigations of PLA, PLA PhytPip and PLA PhytArg lead to a steep incline in HRR to peak heat release rate (pHRR). Values are provided in Table 1. PLA PhytMel containing compounds exhibited prolonged burning and protective layer. PLA PhytLig, PLA PhytEG, PLA Mel (pHRR >1000) were investigated but proved inferior to PLA PhytMel, PLA PhytMel Lig and PLA PhytMel EG. THR was reduced in all Phyt compounds. Intumescence was observed in all compounds except for PLA Lig, PLA PhytLig and PLA PhytMel Lig. PLA PhytMel EG proved as the most effective compound in fire testing with a firm, coherent and intumescent char structure. This study provides an understanding of Phyt as a FR. It systematically improves Phyts effectiveness and processability in PLA. This evidence T2 - 20th European Meeting on Fire Retardant Polymeric Materials (FRPM2025) CY - Madrid, Spain DA - 03.06.2025 KW - Polylactide acid KW - Intumescence KW - Phosphorous flame retardant KW - Phytic acid PY - 2025 AN - OPUS4-63395 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Häßler, Dustin T1 - Neues zum Brandschutz in Stahlbauten N2 - Editorial für die Septemberausgabe 2025 der Zeitschrift Bauingenieur KW - Brandschutz KW - Stahlbau KW - Reaktive Brandschutzsysteme KW - Modulbau PY - 2025 VL - 2025 IS - 9 SP - A3 EP - A3 PB - VDI Fachmedien GmbH & Co. KG CY - Düsseldorf AN - OPUS4-64034 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schartel, Bernhard T1 - Flammschutz von Faserverbundwerkstoffen: Grundlagen und Konzepte N2 - Vor allen Kurz- und Lang-Glasfaser-verstärkte, aber auch Carbonfaser verstärkte Faserverbundwerkstoffe werden in Schienenfahrzeugen eingesetzt. Dabei sind die Brandschutzanforderungen entsprechend EN 45545 zu erfüllen. Der Übersichtsvortrag führt in die Grundlagen des Brandverhaltens und des Flammschutzes von Compositen ein. Anhand von eigenen Arbeiten wird verdeutlicht, dass Flammschutz maßgeschneidert für Composite, die Matrix und für den zu bestehenden Brandtest erforderlich ist. T2 - SKZ Fachtagung Faserverbundwerkstoffe im Schienenfahrzeugbau CY - Merseburg, Germany DA - 14.05.2025 KW - Faserverbundwerkstoffe KW - Composite KW - Flammschutz KW - Brandverhalten PY - 2025 AN - OPUS4-63123 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Chacon Castro, Jose P. T1 - Flame Retardant Polylimonen Carbonate: Material Innovation as a Game Changer N2 - Main message: This research seeks to understand and identify the most promising approaches to enhance the flame resistance of poly(limonene carbonate) (PLimC). Furthermore, the goal is to develop a PLimC-based material that incorporates halogen-free flame retardants (FRs) that are not only highly effective but also environmentally sustainable, contributing to the advancement of greener materials for safer use. Introduction The plastic industry depends on fossil-based materials, causing environmental concerns. PLimC, a sustainable polymer derived from limonene and CO₂ [1], offers a promising alternative. Its use in fire safe applications underscores the need to optimize its performance. This study evaluates halogen free FRs to identify and understand the most promising approaches to enhance PLimC’s flame resistance, aiming to improve fire safety and support eco-friendly material development. Experimental: This study has as its main task to conduct experimental evaluations to analyze the thermal properties, flammability, and fire behavior of each system. Pyrolysis, together with the evolved gases of the samples, were analyzed by thermogravimetric analysis coupled with a FTIR spectrometer. The energy content was determined by using a bomb calorimeter. The flammability of the samples was assessed by the reaction to small flame tests such as the UL 94 burning chamber and limiting oxygen index (LOI). The burning behavior in forced flamed conditions was evaluated using the cone calorimeter. Results and Discussion: Thermal properties were first evaluated to gain a deeper understanding of the pure PLimC thermal stability and fire behavior. This analysis builds on PLimC's structural similarity to polycarbonate (PC), due to its carbonate group, and to polyolefins (PO), due to its aliphatic limonene-derived segment, providing insights into optimizing PLimC for sustainable, fire-safe applications. The initial results, which defined our starting point, showed that the LOI of PLimC was 17.2%, very close to that of PO such as polyethylene (PE) and polypropylene (PP) (~18%). In contrast, PC has a higher LOI of ~24%. Additionally, PLimC did not produce any char (0 wt.-%), similar to PO, whereas PC forms char due to its phenolic structures. The effective heat of combustion of PLimC, measured using bomb calorimetry, was determined to be 31.1 MJ/kg. This value is comparable to that of PC (~30 MJ/kg) but significantly lower than PO (~44 MJ/kg). These findings, which demonstrated similarities to both PO and PC, prompted the evaluation of various commercially available FRs at standard market concentrations. Four halogen-free FR systems were chosen for evaluation: 1. mixture of APP (20 wt.-%) + pentaerythritol (10 wt.-%) as an intumescent system [PLimC / APP / Penta], 2. mixture of the phosphorus compound PX200® (16 wt.-%) + PTFE (0.4 wt.-%) as antidripping [PLimC / PhosC / PTFE], 3. metal hydroxide ATH (50 wt.-%) [PLimC / ATH], and the potassium sulfonate salt Bayowet® (0.4 wt.-%) [PLimC / SulfS]. The concentrations were decided according to the standards used in the industry for polyolefins (system 1 and 3), the mixture polycarbonate / ABS (system 2) and polycarbonates (system 4). PLimC has the usual behavior of a non-charring specimen (fast burning and high peak of heat release). ATH proved to be the most effective flame retardant, achieving the biggest reductions in the effective heat of combustion (EHC) and total heat evolved (THE), as demonstrated by cone calorimeter measurements. Additionally, ATH achieved the highest increase in the LOI (17.1% —> 26.0%). With these results, we understood that the FRs commonly used with polyolefins (at concentrations standard in the industry) exhibit similar behavior in terms of flammability and flame retardancy when applied to PLimC. Although ATH has proven to be an effective flame retardant for PLimC, offering a sustainable solution due to its abundance, non-toxicity, and low environmental impact, we aim to explore bio-based flame retardants to further enhance the material’s sustainability. Since phytic acid salts [2] and lignin [3] have demonstrated flame retardant efficacy in polyolefins, we believe these compounds could also perform well in our system. Phytic acid salts are particularly promising due to their high phosphorus content—and in some cases, nitrogen—which promotes char formation and enhances flame retardancy. Lignin’s unique ability to promote charring could significantly improve flame retardancy, due to the fact that PLimC like polyolefins, lacks inherent char formation. By integrating these bio-based flame retardants, we move closer to developing a fully sustainable material that aligns with the Sustainable Development Goals of the United Nations, contributing to a greener and more resilient future. T2 - 20th European Meeting on Fire Retardant Polymeric Materials (FRPM2025) CY - Madrid, Spain DA - 03.06.2025 KW - Poly(limonene carbonate) KW - Sustainability KW - Halogen free flame retardants PY - 2025 AN - OPUS4-63397 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sałasińska, K. T1 - Bio-sourced Flame Retardant System for Engineering Plastics N2 - Main message: Intumescent flame retardant degradation products react with the lignocellulose hydroxyl groups by esterification, causing enhanced effectiveness in char formation [1]. The aim of this work is to prepare polyamide 11 with lower flammability by modifying it with a plant-based flame retardant system. An innovation is the thermal modification of plant raw materials to establish bio-sourced flame-retardant systems dedicated to engineering materials. Introduction: Using plant fillers to modify engineering materials raises concerns due to too low thermal stability and problems during processing. However, substances participating in char formation, such as cellulose and lignin, have higher decomposition temperatures than the processing temperature of most engineering plastics. Appropriate preparation of lignocellulosic materials through modification by thermal methods will enable their partial decomposition in controlled conditions and eliminate components with low thermal stability. Results and Discussion: For PA11, the heat release (HRR) curve is characterized by two peaks (Fig.1), with a maximum value at the end of burning. The flame retardant systems caused the curves to flatten, which was especially visible for samples with the highest sunflower husk share. The maximum values of heat release rate (pHRR) for samples with FRs varied from 991 to 626 kW/m2 and were much lower compared to PA11 (2152 kW/m2) and MPP (1234 kW/m2). All samples with FRs ignited much earlier than the reference materials, especially compared to unmodified polymer (Tab.1). The maximum average rate of heat emission (MARHE), used to forecast flame spread, decreased compared to PA11 (maximum by 30%) and slightly to MPP. Decreases were also noted in the case of total heat emission (THE), corresponding to the total heat released at the end of flame combustion. The values range from 112 to 127, and depending on the series, an increase (SH) or decrease (SHT) with the growth of the amount of bio-based components was observed. The reduction in THE follows from incomplete combustion as an effect of char forming or reduced combustion efficiency [2]. Char formation was proved by an increase in the yield of residue , while a slight decrease in the effective heat of combustion (EHC) suggests activity in the gas phase. Smoke emission was assessed by specific extinction area (SEA). The SEA reduction was noted only for the MPP sample, and introducing sunflower husks increased the smoke released. T2 - 20th European Meeting on Fire Retardant Polymeric Materials (FRPM2025) CY - Madrid, Spain DA - 03.06.2025 KW - Bio-sourced flame retardant systems KW - Engineering plastics KW - Cone calorimetry PY - 2025 AN - OPUS4-63398 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sanchez-Olivares, G. T1 - Fire Behaviour and Viscoelasticity of Sustainable Thermoplastic Polyurethane Multicomponent Systems N2 - Main message: An interesting influence of viscoelastic properties on fire behavior of multicomponent systems based on thermoplastic polyurethane using industrial-waste leather fibers was observed. A detailed investigation on rheological properties, morphology, pyrolysis, flammability and forced flaming combustion highlighted that fire retardancy is best achieved when the multicomponent systems exhibit a predominant elastic behavior. Introduction: Multicomponent systems represent a sustainable alternative to traditional high-loaded flame retardant polymer materials, particularly in local areas where industrial-waste fibers are a problem.The final properties of those systems greatly depend on the melt blending process [1-2]. In this work,thermoplastic polyurethane multicomponent systems using industrial-waste leather fibers and a commercial flame-retardant additive were produced and investigated. Results and Discussion: According to rheological measurements, the viscoelastic behavior of the TPU multicomponent systems depends on the melt blending process conditions. Systems produced under low blending temperature profile and high rotational speed (TPU/5LF/5APP_T1/V3) display a predominant viscous behavior, meanwhile TPU/5LF/5APP_T1/V1 and TPU/5LF/5APP_T2/V2 samples, exhibit a more elastic one. The combination of LF and APP at low loadings (5 phr each) results in an important reduction on the peak of heat release rate (pHRR), total heat evolved (THE) and total smoke production (TSP) regarding to pure TPU. The UL94 vertical test pointed out that multicomponent systems with predominant elastic behavior (TPU/5LF/5APP_T1/V1 and TPU/5LF/5APP_T2/V2 samples) reached the V-0 rating, meanwhile for the system with the most viscous tendency (TPU/5LF/5APP_T1/V3), non-rating is obtained. Acknowledgement: Part of this work was funded by the Consejo Nacional de Humanidades Ciencias y Tecnologías (CONAHCYT), Mexico, grant number CF-2023-I-865. T2 - 20th European Meeting on Fire Retardant Polymeric Materials (FRPM2025) CY - Madrid, Spain DA - 03.06.2025 KW - TPU KW - Fire behavior KW - Viscoelastic properties KW - Leather fibers KW - Industrial wastes PY - 2025 AN - OPUS4-63400 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Dudziak, Mateusz T1 - Synergistic effect of commercial and natural flame retardants in polylactide biocomposites N2 - Main message: We propose a combination of natural biomass from algae species Desmodesmus sp.along with commercially available flame retardant Melapur200 (melamine polyphosphate) in different mass ratios. We have successfully demonstrated that the use of both of them in PLA matrix biocomposites shows a synergistic flame retardant effect. Introduction: Poly(lactic acid) (PLA), a biodegradable polymer produced from renewable resources such as corn starch and sugarcane, is increasingly being used as a substitute for traditional petrochemical-based polymers in various commercial applications. However, its flammability characteristics need improvement to enable its use as a technical polymer. Based on previous successful experiments on PLA biocomposites with phosphor-enriched algae as filler [1], it was even mandatory to continue with enhancement of PLA flame retardancy. Therefore, tests for PLA biocomposites with P-algae containing melamine polyphosphate at different mass ratios were performed. Pyrolysis, reaction to small fire and fire behavior tests were carried out. Results and Discussion: Thermal stability analyses showed that all composites decompose earlier at lower temperature than pure PLA to a small extent. The evolved gases analysis revealed the release of ammonia and phosphates for the composites tested. PCFC analysis showed the greatest decrease in pHRR for the sample containing Melapur200/Algae (Figure 1A). Similarly, in the fire behaviour analysis, the best result was obtained for the sample containing a mixture of Melapur200 and Algae (Figure 1B). Satisfying results were obtained in the tests of reaction to small flame, where all the samples passed the classification from V-2 to V-0 (in the UL 94 test) and the oxygen index for the best sample was 27.4 +- 0.2%. When only Melapur200 or algae are added separately, a slight flame retardant effect is visible, however if both materials are added in suitable mixtures to the polymer, a synergistic effect is observable. In some cases, it can even be observed that the synergistic effect has surpassed expectations from the superposition. In conclusion, the combination of Melapur200 together with microalgae gives satisfying flame retardant effects for PLA biocomposites. Acknowledgement: The authors thank Dr. Georgios Mourgas (Tecnaro GmbH), and Dr. Michael Schweizer (Tecnaro GmbH) for their contributions to conceptualizing the project, raising the grant, and supporting this work. Thanks to Dr. Robert Gleuwitz (formerly of the BAM), Dr. Claudia Thomsen (iSeaMC GmbH) and Prof. Dr. Laurenz Thomsen (formerly of Jacobs University Bremen, now University of Gothenburg), Thanks to the financial support of the Bundesministerium für Bildung und Forschung – BMBF: KMU-innovativ: Biooekonomie 031B1289B T2 - 20th European Meeting on Fire Retardant Polymeric Materials (FRPM2025) CY - Madrid, Spain DA - 03.06.2025 KW - Polylactide KW - Melamine polyphosphate KW - Microalgae KW - Synergism PY - 2025 AN - OPUS4-63399 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Chacon Castro, Jose P. T1 - Flame retardant poly(limonene carbonate): material innovation as a game changer N2 - The global plastic industry relies on fossil-based materials, presenting significant environmental challenges. Poly(limonene carbonate) (PLimC), a sustainable alternative, is made from two renewable monomers: limonene oxide, derived from non-food sources, and CO₂, positioning it as a promising material for applications requiring flame retardants (FRs) to meet fire safety standards. Thermal properties were initially assessed to better understand the thermal stability and fire behavior of PLimC. This analysis builds on PLimC's unique structural characteristics: its carbonate group resembling polycarbonate (PC) and its aliphatic limonene-derived segment resembling polyolefins (PO). The initial results revealed similarities to both PO and PC, prompting the evaluation of various commercially available flame retardants (FRs) at standard market concentrations. Four halogen-free FR systems were chosen for evaluation, with the conclusion that ATH proved to be the most effective FR, decreasing the heat release rate and the total heat evolved. With these results, we understood that the FRs commonly used with polyolefins (at concentrations standard in the industry) exhibit similar behavior in terms of flammability and flame retardancy when applied to PLimC. While ATH has proven to be an effective FR for PLimC, we aim to investigate bio-based alternatives to further improve the material's sustainability. Phytic acid salts and lignin have shown excellent FR performance in PO, and we believe these compounds could achieve similar success in our system. Their integration could bring us closer to achieving a fully sustainable material that aligns with current environmental goals. T2 - EPF European Polymer Congress 2025 CY - Groningen, Netherlands DA - 22.06.2025 KW - Poly(limonene carbonate) KW - Sustainability KW - Flame retardancy KW - CO2 as monomer KW - Fire Behavior PY - 2025 AN - OPUS4-63668 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Dudziak, Mateusz A1 - Bhatia, Riya A1 - Dey, R. A1 - Falkenhagen, Jana A1 - Ullrich, M. S. A1 - Thomsen, C. A1 - Schartel, Bernhard T1 - Wastewater phosphorus enriched algae as a sustainable flame retardant in polylactide N2 - Revolutionizing our polymer industry for adaption to a sustainable carbon circular economy has become one of today’s most demanding challenges. Exploiting renewable resources to replace fossil-fuel—based plastics with biopolymers such as poly(lactic acid) (PLA) is inevitable while using waste streams as a raw material resource at least is promising. When it comes to using PLA as technical polymer, its high flammability must be addressed by flame retardants compatible with the thermoplastic processing of PLA and its compostability. This study proposes microalgae enriched with phosphorus from wastewater (P-Algae) as an elegant way towards a kind of sustainable organophosphorus flame retardant. The concept is demonstrated by investigating the processing, pyrolysis, flammability, and fire behavior of PLA/P-Algae, while varying the P-Algae content and comparing P-Algae with four alternative bio-fillers (phosphorylated lignin, biochar, thermally treated sewage sludge, and metal phytate) with different P-contents as meaningful benchmarks. KW - PLA KW - Flame Retardancy KW - Phosphorylated Algae KW - Wastewater flame retardants KW - Zink phytate KW - Phosphorylated lignin KW - Thermally treated sludge PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-604150 DO - https://doi.org/10.1016/j.polymdegradstab.2024.110885 SN - 1873-2321 SN - 0141-3910 VL - 227 SP - 1 EP - 11 PB - Elsevier Ltd. AN - OPUS4-60415 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Vega Puga, E. A1 - Wachtendorf, Volker A1 - Kömmling, Anja A1 - Brendelberger, S. A1 - Jaunich, Matthias A1 - Sattler, C. T1 - Lifetime prediction and degradation assessment of FKM and FFKM O-rings under high temperature thermo-oxidative ageing N2 - To support the development of solar reactor technologies for hydrogen production, this study investigates the thermo-oxidative degradation mechanisms of fluorinated elastomers and predicts their lifetimes at high temperatures (200–300 ◦C) consistent with the application requirements. An accelerated ageing programme is conducted with FKM and FFKM O-rings and flat samples for up to 21 days. Optical microscopy is used to analyse the exposed seals’ morphological changes, while IR microscopy is utilised to investigate the underlying chemical degradation mechanisms of both elastomers. Findings suggest that FKM’s degradation arises from dehydrofluorination of the polymer, followed by chain scission and backbone cleavage as a result of the oxidation of newly formed C=C double bonds. FFKM’s degradation is primarily associated with chain scission, but there is also indication that post-curing processes may occur during material ageing. Furthermore, hardness, equilibrium compression set (CS), continuous compression stress relaxation (CSR) and leakage rate tests are used to evaluate changes in the mechanical properties and sealing performance of the elastomers. Equilibrium CS data is extrapolated using time-temperature shifts (TTS) and used to derive an end-of-life criterion of 75 % equilibrium CS, which correlates to leakage rates higher than a predetermined threshold. Service lifetime predictions of FKM and FFKM O-rings at several temperatures are performed and a seal operating temperature of 200 ◦C is suggested, which ensures reasonable O-ring replacement intervals of more than half a year in the solar reactor for both considered materials. KW - Fluoroelastomer KW - Perfluoroelastomer KW - Thermo-oxidative ageing KW - Lifetime prediction KW - Compression set PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-630112 DO - https://doi.org/10.1016/j.polymertesting.2025.108820 SN - 1873-2348 VL - 147 SP - 1 EP - 17 PB - Elsevier BV CY - Amsterdam AN - OPUS4-63011 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Farhan, Muhammad A1 - Schneider, Ronald A1 - Thöns, Sebastian A1 - Gündel, M. T1 - Probabilistic cost modeling as a basis for optimizing inspection and maintenance of turbine support structures in offshore wind farms N2 - The operational management of offshore wind farms includes inspection and maintenance (I&M) of the wind turbine support structures. These activities are complex and influenced by numerous uncertain factors that affect their costs. The uncertainty in the I&M costs should be considered in decision value analyses performed to optimize I&M strategies for the turbine support structures. In this paper, we formulate a probabilistic parametric model to describe I&M costs for the common case in which a wind farm is serviced and maintained using a workboat-based strategy. The model is developed based on (a) interviews with a wind farm operator, engineering consultants, and operation and maintenance engineers, as well as (b) scientific literature. Our methodology involves deriving the probabilistic models of the cost model parameters based on intervals representing a subjective expert opinion on the foreseeable ranges of the parameter values. The probabilistic cost model is applied to evaluate the total I&M costs, and a sensitivity analysis is conducted to identify the main cost drivers. The model can be utilized to optimize I&M strategies at the component, structural system, and wind farm level. To illustrate its potential use, we apply it in a numerical study in which we optimize I&M strategies at the structural system level and identify and demonstrate a simplified approach of capturing uncertain I&M costs in the optimization. The simplified approach is generalized and made available for maintenance cost optimization of offshore wind turbine structures. KW - Inspection KW - Maintenance KW - Turbine support structures KW - Offshore wind KW - Costs PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-626144 DO - https://doi.org/10.5194/wes-10-461-2025 VL - 10 IS - 2 SP - 461 EP - 481 AN - OPUS4-62614 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Mezhov, Alexander A1 - Bright, Asante A1 - Schmidt, Wolfram T1 - Increasing the Incorporation of CO2-Sequestering Materials in Concrete N2 - Concrete is the most widely used construction material accounting for approximately half of all human production throughout history. The production of one ton of cement emits around 600 kg of CO2. With a global cement production estimate of 4.2 billion tons, this results in about 2.5 billion tons of CO2 emissions. This accounts for roughly 7.2% of the total global carbon emissions in 2021. Strategies to decrease carbon emissions in the cement and concrete industry include carbon capture and storage (CCS), reduced binders like ordinary Portland cement (OPC) clinker and optimizing material use through improved processes and structural design. This also means changing architectural vision [6], avoiding concrete where its structural performance is not required and use alternative materials instead, and optimizing the communication among the entire production value chain. T2 - 1st International Conference on Net-Zero Built Environment: Innovations in Materials, Structures, and Management Practices (Net-Zero Future 2024) CY - Oslo, Norway DA - 19.06.2025 KW - Concrete KW - CO2-Sequestering PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-638531 DO - https://doi.org/10.1007/978-3-031-69626-8_4 VL - 237 SP - 39 EP - 48 PB - Springer Nature Switzerland AG CY - Schweiz AN - OPUS4-63853 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Mezhov, Alexander A1 - Goncharov, A. A1 - Zhutovsky, S. A1 - Kovler, K. A1 - Diesendruck, Ch. E. T1 - The Impact of DNA as a Chemical Admixture for Cementitious Materials N2 - Viscosity modifying agents (VMA) and superplasticizers (SP) are two common macromolecular admixture types for cementitious materials. VMAs are used to stabilize fresh cementitious materials, while SPs are used to disperse them. Most VMAs are bio-based polysaccharides that act in the water phase between particles; while most SPs are synthetic comb polymers, consisting of negatively charged backbones that help their adsorption to the cement particles' surface. The molecular structure of DNA contains elements of VMA – as it is a polysaccharide – and SP – as it is a polyanion. In this study, rheological measurements are used to compare how these three types of macromolecules (VMA, SP, and DNA) affect cementitious materials. It is found that DNA shows the combined effects of VMAs and SPs on cement paste: it lowers yield stress while at the same time maintaining or even increasing its viscosity, which permits reducing water content while avoiding bleeding or segregation of samples. Yet, the presence of DNA has a significant retardation impact on cement hydration, which is also a common side effect of VMAs and SPs. KW - Impact of DNA KW - Viscosity modifying agents (VMA) KW - Superplasticizers (SP) PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-638542 DO - https://doi.org/10.1002/admt.202500073 SN - 2365-709X VL - 10 IS - 14 SP - 1 EP - 8 PB - Wiley-VCH GmbH CY - Weinheim AN - OPUS4-63854 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Robens-Radermacher, Annika T1 - Efficient cooling time optimization in Wire Arc Additive Manufacturing using a multi-layer reduced order model N2 - Additive manufacturing (AM) has transformed the industry by enabling the production of complex geometries and parts with customized properties. Among various AM techniques, wire arc additive manufacturing (WAAM) stands out due to its high deposition rate and low equipment cost. However, WAAM’s complex thermal history poses challenges for real-time simulation, essential for online process control and optimization. Consequently, experimental optimization remains the state-of-the-art approach. A critical parameter to optimize is the cooling phase duration, which prevents structural overheating, controls the molten pool size, and influences the mechanical properties of the final product. For efficient cooling time optimization, a fast-to-evaluate model of the temperature field during multi-layer deposition is necessary. This study proposes a reduced order model (ROM) using the proper generalized decomposition (PGD) method as a powerful tool to minimize computational effort. Given the moving heat source in WAAM processes, a mapping approach is employed to achieve a fully separated representation of the temperature field. Building on the authors’ previous one-layer approach, this contribution extends the model to multiple layers through enhanced mapping and compression techniques. The compression reduces the total number of PGD modes as the number of layers increases. The extended mapping allows computations with a fixed mesh over the simulation time, in contrast to standard methods such as the element birth technique. For cooling time optimization, the cooling duration of each layer is incorporated as PGD variables, enabling time-efficient computation of the temperature field for varying cooling times. The developed ROM is applied to optimize the cooling time of a multiple layer example. Therefore a 5-10 layer wall structure is investigated using the austenitic stainless steel 1.4404 (AISI 316 L). The resulting cooling times and the efficiency of the approach are discussed. T2 - 12th European solid mechanics conference (ESMC) CY - Lyon, France DA - 07.07.2025 KW - Model order reduction KW - Proper generalized decomposition KW - Welding KW - Additive manufacturing KW - Optimzation PY - 2025 UR - https://esmc2025.sciencesconf.org/ AN - OPUS4-63855 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Zaghdoudi, M. A1 - Kömmling, Anja A1 - Böhning, Martin A1 - Jaunich, Matthias T1 - Ageing of elastomers in air and in hydrogen environment - A comparative study N2 - EPDM, HNBR and FKM materials were exposed at 150 ◦C to air under atmospheric pressure and to hydrogen at 50 bar for different ageing times. All measurements after hydrogen exposure were conducted on samples in degassed condition to assess irreversible effects resulting from that exposure and to compare them to those after ageing in air. Density, hardness, tensile properties, compression set, and hydrogen permeability of all samples were analysed. In both ageing environments, HNBR exhibited the most significant changes of material properties. However, for both EPDM and HNBR, considerably less severe ageing effects were observed under hydrogen in comparison to ageing in air. On the other hand, FKM showed about the same low level of deterioration in both ageing environments but exhibited poor resistance against damage due to rapid gas decompression in hydrogen environment that can lead to seal failure. The obtained results may serve as a guidance toward a better understanding for design and utilisation of elastomeric materials in future hydrogen infrastructure components. KW - Rapid gas decompression KW - Condensed matter physics KW - Hydrogen KW - Sustainability and the environment KW - Rubber sealing KW - Renewable energy PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-597417 DO - https://doi.org/10.1016/j.ijhydene.2024.03.053 SN - 0360-3199 SN - 1879-3487 VL - 63 SP - 207 EP - 216 PB - Elsevier CY - Oxford AN - OPUS4-59741 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schilling, Markus A1 - Niebergall, Ute A1 - Marschall, Niklas A1 - Meinel, Dietmar A1 - Böhning, Martin T1 - Relation of craze to crack length during slow crack growth phenomena in high‐density polyethylene N2 - The craze‐crack mechanism occurring in high‐density polyethylene (HDPE) causing slow crack growth and environmental stress cracking is investigated in detail with respect to the relation of crack length and the related craze zone. This is essential for the understanding of the resulting features of the formed fracture surface and their interpretation in the context of the transition from crack propagation to ductile shear deformation. It turns out that an already formed craze zone does not inevitably result in formation of a propagating crack, but could also undergo ductile failure. For the examination, the full notch creep test (FNCT) was employed with a subsequent advanced fracture surface analysis that was performed using various imaging techniques: light microscopy, laser scanning microscopy, scanning electron microscopy, and X‐ray micro computed tomography scan. FNCT specimens were progressively damaged for increasing durations under standard test conditions applying Arkopal, the standard surfactant solution, and biodiesel as test media were used to analyze the stepwise growth of cracks and crazes. From considerations based on well‐established fracture mechanics approaches, a theoretical correlation between the length of the actual crack and the length of the preceding craze zone was established that could be evidenced and affirmed by FNCT fracture surface analysis. Moreover, the yield strength of a HDPE material exposed to a certain medium as detected by a classic tensile test was found to be the crucial value of true stress to induce the transition from crack propagation due to the craze‐crack mechanism to shear deformation during FNCT measurements. Highlights - Progress of crack formation in high‐density polyethylene is analyzed by different imaging techniques - Determined growth rates depend on distinction between craze zone and crack - The ratio of the present crack to the anteceding craze zone is validated theoretically - The transition from crack propagation to ductile shear deformation is identified - An already formed craze zone may still fail by ductile mechanisms KW - Craze-crack mechanism KW - Environmental stress cracking (ESC) KW - Full notch creep test (FNCT) KW - Laser scanning microscopy (LSM) KW - Slow crack growth (SCG) KW - X-ray computed tomography (CT) PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-601831 DO - https://doi.org/10.1002/pen.26698 SN - 1548-2634 VL - 64 IS - 6 SP - 2387 EP - 2403 PB - Wiley AN - OPUS4-60183 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Emamverdi, Farnaz A1 - Huang, J. A1 - Mosane Razavi, Negar A1 - Bojdys, M. J. A1 - Forster, A. B. A1 - Budd, P. M. A1 - Böhning, Martin A1 - Schönhals, Andreas T1 - Molecular Mobility and Gas Transport Properties of Mixed Matrix Membranes Based on PIM‑1 and a Phosphinine Containing Covalent Organic Framework N2 - Polymers with intrinsic microporosity (PIMs) are gaining attention as gas separation membranes. Nevertheless, they face limitations due to pronounced physical aging. In this study a covalent organic framework containing λ5-phosphinine moieties, CPSF-EtO were incorporated as a nanofiller (concentration range 0-10 wt%) into a PIM-1 matrix forming dense films with a thickness of ca. 100 μm. The aim of the investigation was to investigate possible enhancements of gas transport properties and mitigating effects on physical aging. The incorporation of the nanofiller occurred on aggregate level with domains up to 100 nm as observed by T-SEM and confirmed by X-ray scattering. Moreover, the X-ray data show that the structure of the microporous network of the PIM-1 matrix is changed by the nanofiller. As the molecular mobility is fundamental for gas transport as well as for physical aging, the study includes dielectric investigations of pure PIM-1 and PIM-1/CPSF-EtO mixed matrix membranes to establish a correlation between the molecular mobility and the gas transport properties. Using the time-lag method the gas permeability and the permselectivity were determined for N2, O2, CH4 and CO2 for samples with variation in filler content. A significant increase in the permeability of CH4 and CO2 (50 % increase compared to pure PIM-1) was observed for a concentration of 5 wt% of the nanofiller. Furthermore, the most pronounced change in the permselectivity was found for the gas pair CO2/N2 at a filler concentration of 7 wt%. KW - Polymers of Intrinsic Microporosity KW - Nanocomposites PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-595031 DO - https://doi.org/10.1021/acs.macromol.3c02419 SN - 0024-9297 VL - 57 IS - 4 SP - 1829 EP - 1845 PB - ACS Publications AN - OPUS4-59503 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Thuy, Maximilian A1 - Niebergall, Ute A1 - Oehler, H. A1 - Alig, I. A1 - Böhning, Martin T1 - Damaging effect of admixtures used in crop protection products on high density polyethylene packaging material N2 - The phenomenon of environmental stress cracking is still a major issue in materials engineering as well as from a scientific perspective. Especially in the case of packaging materials made of high-density polyethylene, assessing the potential of premature damage due to environmental stress cracking is complex because of the large number of components in possible liquid filling goods. As a first guideline, the well-known effect of detergents and dispersants is usually considered, but the interplay with other components, such as organic solvents is often unknown. Particularly challenging in this respect are crop protection products, consisting of several different admixtures in addition to the biologically active ingredients. This study is based on two model liquids representing these admixtures that were established for testing in this context. The model liquids as well as their constituting components were used as liquid media in the Full Notch Creep Test to characterize the environmental stress cracking behavior of a typical high-density polyethylene. Complementary to the time-to failure of a notched specimen obtained from these tests, the crack opening was monitored optically, and the fracture surface was analyzed post-failure by laser scanning microscopy as well as scanning electron microscopy. Based on the results, the effect of various surfactants as well as the influence of organic solvents on environmental stress cracking are discussed. KW - Environmental stress cracking KW - High-density polyethylene KW - Crop protection products KW - Full notch creep test KW - Fracture surface analysis KW - Crack opening displacement PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-554631 DO - https://doi.org/10.1016/j.polymertesting.2022.107672 SN - 0142-9418 VL - 114 SP - 1 EP - 16 PB - Elsevier Ltd. CY - Amsterdam AN - OPUS4-55463 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Strommer, Bettina A1 - Schulze, Dietmar A1 - Schartel, Bernhard A1 - Böhning, Martin T1 - Networking Skills: The Effect of Graphene on the Crosslinking of Natural Rubber Nanocomposites with Sulfur and Peroxide Systems N2 - Tailored crosslinking in elastomers is crucial for their technical applications. The incorporation of nanoparticles with high surface-to-volume ratios not only leads to the formation of physical networks and influences the ultimate performance of nanocomposites, but it also affects the chemical crosslinking reactions. The influence of few-layer graphene (FLG) on the crosslinking behavior of natural rubber is investigated. Four different curing systems, two sulfur-based with different accelerator-to-sulfur ratios, and two peroxide-based with different peroxide concentrations, are combined with different FLG contents. Using differential scanning calorimetry (DSC), vulcametry (MDR) and swelling measurements, the results show an accelerating effect of FLG on the kinetics of the sulfur-based curing systems, with an exothermic reaction peak in DSC shifted to lower temperatures and lower scorch and curing times in the MDR. While a higher accelerator-to-sulfur ratio in combination with FLG leads to reduced crosslinking densities, the peroxide crosslinkers are hardly affected by the presence of FLG. The good agreement of crosslink densities obtained from the swelling behavior confirms the suitability of vulcameter measurements for monitoring the complex vulcanization process of such nanocomposite systems in a simple and efficient way. The reinforcing effect of FLG shows the highest relative improvements in weakly crosslinked nanocomposites. KW - Nanocomposite KW - Elastomers KW - Graphene KW - Crosslinking KW - Network KW - Rubber KW - Vulcanization PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-560409 DO - https://doi.org/10.3390/polym14204363 VL - 14 IS - 20 PB - MDPI AN - OPUS4-56040 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Strommer, Bettina A1 - Schulze, Dietmar A1 - Schartel, Bernhard A1 - Böhning, Martin T1 - The quantification of anisotropy in graphene/natural rubber nanocomposites: Evaluation of the aspect ratio, concentration, and crosslinking N2 - In the processing of nanocomposites, high shear stresses at elevated tempera-tures orient two-dimensional nanoparticles like graphene. This orientationleads to anisotropic mechanical, thermal or barrier properties of the nanocom-posite. This anisotropy is addressed in this study by comparing graphene (few-layer graphene, FLG) with a nanoscaled carbon black (nCB) at a filler contentof 3 phr, by varying the vulcanization, and by comparing different FLG con-tents. Transmission electron microscopy gives insight into the qualitative ori-entation in the nanocomposite with FLG or nCB. The storage moduli paralleland normal to the orientation reveal the direction dependency of reinforce-ment through dynamic mechanical analysis (DMA). Dimensional swellingmeasurements show a restriction of the expansion parallel to the FLG orienta-tion, and an increased expansion normal to the orientation. The vulcanizationsystem and crosslinking determine the respective level of property values, andhigher crosslinking densities increase the anisotropy in DMA resulting invalues of up to 2.9 for the quantified anisotropy factor. With increasing FLGcontent, the anisotropy increases. A comparison of the results reveals swellingmeasurements as the most suitable method for the determination of anisot-ropy. Compared to recent literature, the presented processing induces higheranisotropy, leading to higher reinforcing effects in the direction of orientation KW - Natural rubber KW - Graphene KW - Nanocomposite KW - Mechanical properties KW - Swelling PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-571522 DO - https://doi.org/10.1002/app.53753 SN - 1097-4628 VL - 140 IS - 16 SP - 1 EP - 15 PB - Wiley online library CY - Hoboken, New Jersey (USA) AN - OPUS4-57152 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Emamverdi, Farnaz A1 - Huang, J. A1 - Szymoniak, Paulina A1 - Bojdys, M. J. A1 - Böhning, Martin A1 - Schönhals, Andreas T1 - Structure and molecular mobility of phosphinine-based covalent organic frameworks – glass transition of amorphous COFs N2 - Two-dimensional covalent organic frameworks (COFs) based on phosphinine and thiophene building blocks have been synthesized with two different side groups. The materials are denoted as CPSF-MeO and CPSF-EtO where CxxF correspond to the covalent framework, whereas P and S are related to heteroatoms phosphorous and sulfur. MeO and EtO indicate the substituents, i.e. methoxy and ethoxy. Their morphologies were studied by scanning electron microcopy and X-ray scattering. The absence of crystalline reflexes in the X-ray pattern reveal that both materials are amorphous and can be considered as glasses. Furthermore, N2 adsorption measurements indicate substantial Brunauer–Emmett–Teller (BET) surface area values pointing to the formation of three-dimensional pores by stacking of the aromatic 2D layer. An analysis of the porosity of both COFs showed a mean radius of the pores to be of ca. 4 nm, consistent with their chemical structure. The COFs form nanoparticles with a radius of around 100 nm. The thermal behavior of the COFs was further investigated by fast scanning calorimetry. These investigations showed that both COFs undergo a glass transition. The glass transition temperature of CPSF-EtO is found to be ca. 100 K higher than that for CPSF-MeO. This large difference in the glass transition is discussed to be due to a change in the interaction of the COF sheets induced by the longer ethoxy group. It might be assumed that for CPSF-EtO more individual COF sheets assemble to larger stacks than for CPSF-MeO. This agrees with the much larger surface area value found for CPSF-EtO compared to CPSF-MeO. To corroborate the results obtained be fast scanning calorimetry dielectric measurements were conducted which confirm the occurrence of a dynamic glass transition. The estimated temperature dependence of the relaxation rates of the dielectric relaxation and their absolute values agrees well with the data obtained by fast scanning calorimetry. Considering the fragility approach to the glass transition, it was further found that CPSF-MeO is a fragile glass former whereas CPSF-EtO behaves as a strong glass forming material. This difference in the fragility points also to distinct differences in the interaction between the 2D COF molecules in both materials. KW - Covalent Organic frameworks PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-596770 DO - https://doi.org/10.1039/d3ma01123b SP - 1 EP - 10 PB - Royal Society of Chemistry (RSC) AN - OPUS4-59677 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Zorn, R. A1 - Lohstroh, W. A1 - Zamponi, M. A1 - Harrison, W. A1 - Budd, P. A1 - Böhning, Martin A1 - Schönhals, Andreas T1 - Molecular mobility of a polymer of intrinsic microporosity revealed by quasielastic neutron scattering N2 - Quasielastic neutron scattering by employing a combination of time-of-flight and backscattering techniques is carried out to explore the molecular mobility of a polymer of intrinsic microporosity (PIM-1) at microscopic time scales in comparison with a high-performance polyimide. Molecular fluctuations can change the structure of the temporary network of micropores and open or close pathways for gas molecules. Therefore, the investigation might help to understand the selectivity of PIMs in gas separation processes. The performed neutron scattering experiments provide evidence for a low-temperature relaxation process, which was assigned to methyl group rotation. This methyl group rotation was analyzed in terms of jump diffusion in a three-fold potential. The analysis results in a fraction of methyl groups which are immobilized. For PIM-1 it was found that the fraction of immobilized methyl groups decreases with increasing temperature up to 350 K. At higher temperatures the number of immobilized methyl group increases gain due to an underlying relaxation process. This motional process on a somewhat larger length scale might lead to a reversible structural rearrangement which partially hinders the strongly localized methyl group rotation. In addition, it was found that the activation energy for the methyl group rotation for PIM-1 and the polyimide is significantly higher than for conventional polymers. KW - Polymer of intrinsic microporosity KW - Quasielastic neutron scattering PY - 2020 DO - https://doi.org/10.1021/acs.macromol.0c00963 SN - 0024-9297 SN - 1520-5835 VL - 53 IS - 15 SP - 6731 EP - 6739 PB - American Chemical Society CY - Washington, DC AN - OPUS4-51147 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kolmangadi, Mohamed Aejaz A1 - Szymoniak, Paulina A1 - Smales, Glen Jacob A1 - Alentiev, D. A1 - Bermeshev, M. A1 - Böhning, Martin A1 - Schönhals, Andreas T1 - Molecular Dynamics of Janus Polynorbornenes: Glass Transitions and Nanophase Separation N2 - For the first time, dielectric and calorimetric investigations of an homologous series of Janus polynorbornenes with rigid main backbones and flexible -Si(OR)3 side groups, of differing length alkyl chains (R = Propyl, Butyl, Hexyl, Octyl, Decyl) is reported. Generally, this class of polymers has some potential for applications in the field of gas separation membranes. Two dielectrically active processes are observed at low temperatures, denoted as β- and α- relaxation. The former can be assigned to localized fluctuations, whilst the latter is related to the glassy dynamics of the flexible -Si(OR)3 side groups, creating a nanophase separation in both the alkyl chain rich and backbone rich domains. This is confirmed through temperature modulated DSC measurements and X-ray scattering experiments. The glass transition temperatures of the backbone rich domains, which are beyond or near to their degradation temperatures in terms of conventional DSC, are determined for the first time using Fast Scanning Calorimetry employing both fast heating and cooling rates. This is complimented with scattering experiments that show how the size of the alkyl chain rich domains increases with chain length. Alongside these results, a significant conductivity contribution was observed for all poly(tricyclononenes) with -Si(OR)3 side groups, which is interpreted in terms of a percolation model. KW - Polynorbornenes KW - Broadband Dielectric Spectrscopy KW - Advanced calorimetry PY - 2020 DO - https://doi.org/10.1021/acs.macromol.0c01450 VL - 53 IS - 17 SP - 7410 EP - 7419 PB - ACS AN - OPUS4-51196 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schönhals, Andreas A1 - Szymoniak, Paulina A1 - Kolmangadi, Mohamed Aejaz A1 - Böhning, Martin A1 - Zamponi, M. A1 - Frick, B. A1 - Appel, M. A1 - Günther, G. A1 - Russina, M. A1 - Alentiev, D. A1 - Bermeshev, M. A1 - Zorn, R. T1 - Microscopic dynamics of highly permeable super glassy polynorbornenes revealed by quasielastic neutron scattering N2 - The molecular dynamics of addition-type poly(tricyclononenes) with Si-substituted bulky side groups has been investigated by a combination of neutron time-of-flight and neutron backscattering spectroscopy methods on a time scale from 0.1 ps to ca. 3 ns. The investigated poly(tricyclononenes) PTCNSi1 and PTCNSi2g both bear a high microporosity which makes them promising candidates for active separation layers for gas separation membranes. At least for larger gas molecules it is assumed that the pathways for diffusion require an enlargement of pre-existing micropores in terms of an activated zone. A low temperature relaxation process was found for both polymers by the performed neutron scattering experiments. This process was assigned to the methyl group rotation. It was analysed in terms of a jump diffusion in a three-fold potential. The analysis of the dependence of the elastic incoherent structure factor on the scattering vector yields the number of methyl groups which might be immobilized. For PTCNSi1 (3 methyl groups in the monomeric unit) it was found that all methyl groups take part in the methyl group rotation whereas for PTCNSi2g (6 methyl groups in monomeric unit) a considerable number of methyl groups are blocked in their rotation. This immobilization of methyl groups is due to the sterically demanding arrangement of the methyl groups in PTCNSi2g. This conclusion is further supported by the result that the activation energy for the methyl group rotation is three times higher for PTCNSi2g than that of PTCNSi1. KW - Highly permeably polynorbornenes KW - Polymers of intrinsic microporosity KW - Gas separation membranes KW - Quasielastic neutron scattering PY - 2021 DO - https://doi.org/10.1016/j.memsci.2021.119972 SN - 0376-7388 VL - 642 PB - Elesevier B.V. AN - OPUS4-53508 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kolmangadi, Mohamed Aejaz A1 - Szymoniak, Paulina A1 - Smales, Glen Jacob A1 - Bermeshev, M. A1 - Schönhals, Andreas A1 - Böhning, Martin T1 - Molecular mobility of polynorbornenes with trimethylsiloxysilyl side groups: Influence of the polymerization mechanism N2 - We report dielectric and calorimetric studies on metathesis and addition-type polytricyclononenes, both based on the same monomer bearing three pendant OSiMe3 groups. For the addition-type polymer, dielectric spectroscopy reveals a β*-process related to the microporosity, whereas for its metathesis counterpart, the segmental dynamics manifests as an α-process related to a glass transition. Besides active dielectric processes, a significant conductivity contribution is detected for both samples which for the microporous additiontype polymer is three orders of magnitude greater than for the metathesis polymer. The broadband dielectric spectroscopy is complemented by detailed calorimetric investigations, comprising DSC, FSC, and TMDSC. The calorimetric methods detected the glass transition for the metathesis polymer in agreement with the observed dielectric α-process. Furthermore, the already reported gas transport properties for both polymers are compared, setting them in correlation with the observed molecular mobility and conductivity behavior. The discussed results reflect significant differences in molecular mobility of the two polymers affecting the appearance of microporosity which strongly determines the gas transport properties. KW - Microporous polymers KW - Molecular mobility KW - Electrical conductivity KW - Membrane polymers KW - Gas separation PY - 2022 DO - https://doi.org/10.22079/JMSR.2021.538060.1495 SN - 2476-5406 VL - 8 IS - 3 SP - 1 EP - 9 PB - Membrane Processes Research Laboratory (MPRL) CY - Tehran AN - OPUS4-54303 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Zorn, R. A1 - Szymoniak, Paulina A1 - Kolmangadi, Mohamed Aejaz A1 - Wolf, M. A1 - Alentiev, D. A1 - Bermeshev, M. A1 - Böhning, Martin A1 - Schönhals, Andreas T1 - Low frequency vibrational density of state of highly permeable super glassy polynorbornenes – The Boson peak N2 - Inelastic incoherent neutron time-of flight scattering was employed to measure the low frequency density of states for a series of addition polynorbornenes with bulky side groups. The rigid main chain in combination with the bulky side groups give rise to a microporosity of these polymers in the solid state. The microporosity characterized by the BET surfaces area varies systematically in the considered series. Such materials have some possible application as active separation layer in gas separation membranes. All investigated materials show excess contributions to the Debye type density of states characteristic for glasses known as Boson peak. The maximum position of the Boson peak shifts to lower frequency values with increasing microporosity. Data for PIM-1 and Matrimid included for comparison are in good agreement to this dependency. This result supports the sound wave interpretation of the Boson peak. KW - Polynorbornes KW - Neutron Scattering PY - 2020 DO - https://doi.org/10.1039/d0cp03360j SN - 1463-9076 VL - 22 IS - 33 SP - 18381 EP - 18387 PB - Royal Chemical Society AN - OPUS4-51165 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schönhals, Andreas T1 - Physical investigations on Super glassy Polymers having possible applications in gas Separation Membranes N2 - The properties of polymers of intrinsic microporosity were investigated by fast scanning calorimetry, dielectric spectroscopy and neutron scattering T2 - University of Pennsylvania CY - Online meeting DA - 25.01.2021 KW - Polymer of intrisic microporosity PY - 2021 AN - OPUS4-52065 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schönhals, Andreas T1 - Inelastic neutron scattering as a tool to investigate  polymers of intrinsic microporosity for green membrane processes and electronic applications N2 - Polymers with intrinsic microporosity are promising candidates for the active separation layer in green gas separation membranes and as active materials for electronic applicatons. Here, by means of inelastic neutron scattering, the vibrational density of states (VDOS) and the molecular mobility were investigated for PIM-1, the prototypical polymer with intrinsic microporosity. The results are compared to data measured for a more conventional high-performance polyimide used in gas separation membranes (Matrimid). The measured data show the characteristic low frequency excess contribution to the VDOS above the Debye sound wave level, generally known as the Boson peak in glass-forming materials. In comparison to the Boson peak of Matrimid, that of PIM-1 is shifted to lower frequencies. This shift is discussed considering the microporous, sponge-like structure of PIM-1 as providing a higher compressibility at the molecular scale than for conventional polymers. Elastic fixed window scans were measured on a neutron backscattering spectrometer to have an overview about the molecular dynamics at a time scale of ca. 1 ns. The temperature dependence of the estimated mean squared displacement shows a step-like increase in the temperature range from 100 K to 250 K indicating the onset of some molecular mobility. The nature of this motional process was analysed in detail by quasielastic neutron scattering combining Time-of-Flight and backscattering where the data are discussed with regard to both the q- and the temperature dependence. T2 - Symposium on Large Scale Facilities CY - Berlin, Germany DA - 09.03.2020 KW - Polymer membranen PY - 2020 AN - OPUS4-50546 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schönhals, Andreas T1 - Vibrational density of states and molecular mobility in a polymer with intrinsic microporosity PIM-1 as revealed by inelastic neutron scattering N2 - Polymers with intrinsic microporosity are promising candidates for the active separation layer in gas separation membranes. Here, by means of inelastic neutron scattering, the vibrational density of states (VDOS) and the molecular mobility were investigated for PIM-1, the prototypical polymer with intrinsic microporosity. The results are compared to data measured for a more conventional high-performance polyimide used in gas separation membranes (Matrimid). The measured data show the characteristic low frequency excess contribution to the VDOS above the Debye sound wave level, generally known as the Boson peak in glass-forming materials. In comparison to the Boson peak of Matrimid, that of PIM-1 is shifted to lower frequencies. This shift is discussed considering the microporous, sponge-like structure of PIM-1 as providing a higher compressibility at the molecular scale than for conventional polymers. Elastic fixed window scans were measured on a neutron backscattering spectrometer to have an overview about the molecular dynamics at a time scale of ca. 1 ns. The temperature dependence of the estimated mean squared displacement shows a step-like increase in the temperature range from 100 K to 250 K indicating the onset of some molecular mobility. The nature of this motional process was analyzed in detail by quasielastic neutron scattering combining Time-of-Flight and backscattering where the data are discussed with regard to both the q- and the temperature dependence. T2 - JCNS Workshop for Neutron Scattering CY - Tutzing at Munich, Germany DA - 07.10.2019 KW - Polymers of Intrinsic Microporosity KW - Neutron Scattering PY - 2019 AN - OPUS4-49271 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Böhning, Martin T1 - The glass transition temperature of Polymers of Intrinsic Microporosity (PIMs) as determined by fast scanning calorimetry N2 - Polymers of intrinsic microporosity (PIMs) have recently emerged as novel materials for a broad range of high-performance applications from gas separation to electronic devices. The very rigid, contorted polymer chains show only limited molecular mobility and therefore pack inefficiently giving rise to intrinsic microporosity with pore sizes generally smaller than 1 nm resulting in BET surface areas larger than 700 m2/g. Using conventional thermal analysis techniques, no glass transition temperature (Tg) of PIMs could be unambiguously detected up to now. Employing fast scanning calorimetry (FSC) based on a one chip sensor, decoupling the time scales responsible for the glass transition and the thermal decomposition is a reliable strategy to overcome this limitation. The FSC device is capable to heat and cool a small sample (ng-range) with ultrafast rates of several ten thousand K/s. Evidence of a glass transition is obtained for a series of PIMs with different chain rigidities. Local small-scale fluctuations are held responsible for the glass transition of highly rigid PIMs rather than segmental motions as in conventional polymers. T2 - International Polymer Processing Society (PPS) - Europe-Africa 2019 Regional Conference (PPS2019) CY - Pretoria, South Africa DA - 18.11.2019 KW - Polymers KW - Polymers of intrinsic microporosity KW - Glass transition KW - Fast scanning calorimetry PY - 2019 AN - OPUS4-49957 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Yin, Huajie A1 - B, Yang A1 - Chua, Y. Z. A1 - Szymoniak, Paulina A1 - Carta, M A1 - Malpass-Evans, R A1 - McKeown, N A1 - Harrison, W A1 - Budd, P A1 - Schick, C A1 - Böhning, Martin A1 - Schönhals, Andreas T1 - Effect of backbone rigidity on the glass transition of polymers of in-trinsic microporosity probed by fast scanning calorimetry N2 - Polymers of Intrinsic Microporosity (PIMs) of high performance have developed as materials with a wide application range in gas separation and other energy-related fields. Further optimization and long-term behavior of devices with PIMs require an understanding of the structure-property relationships including physical aging. In this context the glass transi-tion plays a central role, but with conventional thermal analysis a glass transition is usually not detectable for PIMs be-fore their thermal decomposition. Fast scanning calorimetry provides evidence of the glass transition for a series of PIMs, as the time scales responsible for thermal degradation and for the glass transition are decoupled by employing ultrafast heating rates of tens of thousands K s-1. The investigated PIMs were chosen considering the chain rigidity. The estimated glass transition temperatures follow the order of the rigidity of the backbone of the PIMs. KW - Polymers of intrinsic microporosity KW - Fast scanning calormetry PY - 2019 DO - https://doi.org/10.1021/acsmacrolett.9b00482 SN - 2161-1653 VL - 8 IS - 8 SP - 1022 EP - 1028 PB - ACS Publications AN - OPUS4-48617 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schönhals, Andreas T1 - Vibrational density of states and molecular mobility in a polymer with intrinsic microporosity PIM-1 as revealed by inelastic neutron scattering N2 - Polymers with intrinsic microporosity are promising candidates for the active separation layer in gas separation membranes. Here, by means of inelastic neutron scattering, the vibrational density of states (VDOS) and the molecular mobility were investigated for PIM-1, the prototypical polymer with intrinsic microporosity. The results are compared to data measured for a more conventional high-performance polyimide used in gas separation membranes (Matrimid). The measured data show the characteristic low frequency excess contribution to the VDOS above the Debye sound wave level, generally known as the Boson peak in glass-forming materials. In comparison to the Boson peak of Matrimid, that of PIM-1 is shifted to lower frequencies. This shift is discussed considering the microporous, sponge-like structure of PIM-1 as providing a higher compressibility at the molecular scale than for conventional polymers. Elastic fixed window scans were measured on a neutron backscattering spectrometer to have an overview about the molecular dynamics at a time scale of ca. 1 ns. The temperature dependence of the estimated mean squared displacement shows a step-like increase in the temperature range from 100 K to 250 K indicating the onset of some molecular mobility. The nature of this motional process was analyzed in detail by quasielastic neutron scattering combining Time-of-Flight and backscattering where the data are discussed with regard to both the q- and the temperature dependence. T2 - 7. European Conference on Neutron Scattering 2019 CY - Saint Petersburg, Russia DA - 30.06.2019 KW - Neutron Scattering KW - Polymer of intrinsic microporosity PY - 2019 AN - OPUS4-48421 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Jaunich, Matthias A1 - Kömmling, Anja A1 - Böhning, Martin A1 - Silbernagl, Dorothee T1 - Comparison of ageing behavior of O-ring seals under hydrogen and air N2 - Elastomeric seals are essential components in the infrastructure which prevent leakage of gas and ensure proper function of technical devices and are therefore highly safety relevant. For proper function a remaining resilience and tolerance to pressure changes is required. The ageing of elastomers is an undesirable but inevitable process leading to a limited lifetime of rubber products such as seals. Independent of the application, as e.g. automotive, piping or container applications, a long lifetime or at least a timely exchange of a seal before occurrence of critical failure is desired. Hydrogen is a key element for the energy turnaround and therefore the compatibility of seals with hydrogen is essential. In addition to the effect of hydrogen uptake and release, which might also cause destructive effects such as rapid gas decompression, ageing at high temperature under hydrogen atmosphere is of interest too. Most of the existing work is addressing the performance of new materials and comprises only very limited investigations concerning long-term use and the behaviour of aged materials in contact with hydrogen. As ageing can lead to substantial changes of material properties, it must be evaluated whether these changes are beneficial or deteriorating for the component function. In this work we present and compare results of the characterization of three sealing materials (EPDM, HNBR, FKM) after ageing at high temperature under hydrogen and air. Despite the common assumption that ageing under hydrogen atmosphere should be less severe for the material in comparison to air ageing, this is not the case for every material. T2 - ASME PVP2025, Pressure Vessels & Piping Conference CY - Montreal, Quebec, Canada DA - 20.07.2025 KW - Aging KW - Seal KW - Compression set KW - Atomic force microscopy PY - 2025 SP - 1 EP - 7 AN - OPUS4-63889 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Jaunich, Matthias T1 - Comparison of Ageing Behavior of O-Ring Seals Under Hydrogen and Air N2 - Elastomeric seals are essential components in the infrastructure which prevent leakage of gas and ensure proper function of technical devices and are therefore highly safety relevant. For proper function a remaining resilience and tolerance to pressure changes is required. The ageing of elastomers is an undesirable but inevitable process leading to a limited lifetime of rubber products such as seals. Independent of the application, as e.g. automotive, piping or container applications, a long lifetime or at least a timely exchange of a seal before occurrence of critical failure is desired. Hydrogen is a key element for the energy turnaround and therefore the compatibility of seals with hydrogen is essential. In addition to the effect of hydrogen uptake and release, which might also cause destructive effects such as rapid gas decompression, ageing at high temperature under hydrogen atmosphere is of interest too. Most of the existing work is addressing the performance of new materials and comprises only very limited investigations concerning long-term use and the behaviour of aged materials in contact with hydrogen. As ageing can lead to substantial changes of material properties, it must be evaluated whether these changes are beneficial or deteriorating for the component function. In this work we present and compare results of the characterization of three sealing materials (EPDM, HNBR, FKM) after ageing at high temperature under hydrogen and air. Despite the common assumption that ageing under hydrogen atmosphere should be less severe for the material in comparison to air ageing, this is not the case for every material. T2 - ASME PVP2025, Pressure Vessels & Piping Conference CY - Montreal, Canada DA - 20.07.2025 KW - Aging KW - Seal KW - Compression set KW - Atomic force microscopy PY - 2025 AN - OPUS4-63888 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Jaunich, Matthias T1 - Elastomerdichtungen für Wasserstoffanwendungen - Vergleich des Alterungsverhaltens in Luft und Wasserstoff N2 - In diesem Beitrag soll ein Fokus auf das Alterungsverhalten von Elastomerdichtungen unter Wasserstoff gelegt werden. Hierfür wurden Untersuchungen bei einem mittleren Wasserstoffdruck über Alterungszeiten von bis zu 100 Tagen durchgeführt. Das Alterungsverhalten wird im Vergleich der Alterungseffekte unter thermooxidativen Bedingungen betrachtet und bewertet. Die Annahme, dass der Alterungseffekt unter Wasserstoff stets weniger ausgeprägt ist als an Luft bestätigt sich nicht durch die Ergebnisse. T2 - 4. O-Ring-Forum der Firma ISGATEC CY - Bad Schönborn, Germany DA - 15.05.2025 KW - Wasserstoff KW - Dichtung KW - Thermische Alterung KW - Elastomer PY - 2025 AN - OPUS4-63135 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kemmler, Samuel A1 - Cuéllar, Pablo A1 - Rettinger, C. A1 - Köstler, H. T1 - A Fluid-Solid Coupled Micromechanical Simulation for the Analysis of Piping Erosion During the Seabed Installation of a Suction Bucket Foundation N2 - Suction buckets are a promising concept for the foundations of offshore wind turbines. During the installation process of a suction bucket, localized fluidization of the granular soil, so-called piping erosion, may lead to installation failure. A 3D fluid-solid coupled micromechanical simulation is presented to study the occurrence of piping. An Euler-Lagrangian coupling employs momentum exchange between the fluid phase and the geometrically resolved particles. We investigate the behavior of the soil for three cases with varying prescribed suction velocities. We observe piping in the case with the highest suction velocity by analyzing the deformation of the granular fabric and monitoring the differential pressure. The grains under the bucket wall-tip show the highest hydraulic gradients and forces at the onset of piping. This approach permits a detailed analysis of piping phenomena and brings novel insights on the triggering conditions for piping failure of suction-aided foundations. T2 - TC 105 International Symposium CY - Grenoble, France DA - 23.09.2024 KW - Micromechanical simulation KW - Piping erosion KW - Suction bucket foundation PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-629461 DO - https://doi.org/10.1088/1755-1315/1480/1/012024 SN - 1755-1307 VL - 1480 IS - 1 SP - 1 EP - 4 PB - IOP Publishing AN - OPUS4-62946 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Thuy, Maximilian A1 - Niebergall, Ute A1 - Oehler, H. A1 - Alig, I. A1 - Böhning, Martin T1 - Evaluation of the damaging effect of crop protection formulations on high density polyethylene using the Full Notch Creep Test N2 - Four typical high-density polyethylene container materials were used to investigate damage or stress cracking behavior in contact with model liquids for crop protection products. These model liquids are established in German regulations for the approval of dangerous goods containers and consist of typical admixtures used for crop protection products but without biological active ingredients. This study is performed with the standardized method of Full Notch Creep Test, adapting the media temperature to 40 °C according to the usual conditions where these test liquids are applied. The two model liquids differ into a water-based solution and a composition based on different organic solvents which are absorbed by the material up to significant levels. Therefore, extensive sorption measurements are performed. The fracture surfaces obtained are analyzed in detail not only by light microscopy, but also by laser scanning microscopy as well as scanning electron microscopy. Influence of pre-saturation and applied stress are addressed by respective systematic series of experiments. KW - Polyethylene KW - Full Notch Creep Test KW - Environmental Stress Cracking KW - Fracture PY - 2021 DO - https://doi.org/10.1016/j.polymer.2021.123853 SN - 0032-3861 VL - 228 SP - 123853 PB - Elsevier Ltd. AN - OPUS4-52686 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schilling, Markus T1 - Addressing ESC using FNCT enhanced by optical fracture surface analysis N2 - During their lifetime, polymer components subjected to mechanical loads and environmental influences show a loss of their mechanical properties required for their specific applications. In this respect, the craze-crack damage mechanism slow crack growth (SCG) is relevant for PE-HD components used in high-performance applications such as pipes and containers for the storage and transport of dangerous goods. SCG is considered to be the major failure mechanism in polyolefins and it typically occurs suddenly and unexpectedly. Due to the fields of application, SCG is a safety relevant issue. To test for the resistance of PE-HD pipe and container materials against SCG, the full-notch creep test (FNCT) is widely applied in Europe. In this study, SCG phenomena in PE-HD are investigated in detail based on an improved FNCT, especially including the consideration of the influence of environmental liquids effecting the damage mechanism. Using an enhanced fracture surface and a crack propagation analysis with imaging techniques such as light microscopy (LM), laser scanning microscopy (LSM), X-ray computed tomography (CT-scan) and scanning electron microscopy (SEM), detailed data concerning SCG are obtained. The combined application of FNCT and such imaging techniques is explicitly advantageous and recommended to gain important information on damage occurring to PE-HD induced by mechanical stress and the influence of environmental liquids, which is essential within the Fourth Industry Revolution. T2 - PPS Europe-Africa 2019 Regional Conference (PPS 2019) CY - Pretoria, South Africa DA - 18.11.2019 KW - Polyethylene, PE-HD KW - Full-Notch Creep Test (FNCT) KW - Fracture surface analysis KW - Slow crack growth KW - Environmental stress cracking KW - Laser Scanning Microscopy (LSM) KW - Scanning Electron Microscopy (SEM) PY - 2019 AN - OPUS4-50939 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Böhning, Martin T1 - Environmental Stress Cracking in PE-HD – Assessment of Crack Propagation and Mechanisms by Optical Methods N2 - Slow crack growth (SCG) under the influence of external fluid media, usually termed environmental stress cracking (ESC), is still one of the most frequent origins of severe damage and failure of polymeric materials. For polyethylene (PE) this is relevant for mass products, like bottles for consumer products, but also for high-performance materials for pipes or industrial packaging, including containers for chemicals and other dangerous goods. Especially for high-density polyethylene (PE-HD) the susceptibility to SGC and ESC is depending on the complex interplay between molecular weight and architecture and the resulting semicrystalline morphology, especially the formation of tie-molecules. A reliable assessment of the resistance against this damage phenomenon is essential for demanding as well as safety-critical applications and has to take into account suitable testing methodologies and conditions in combination with environmental media reflecting the properties representative for typical fillings and relevant components causing ESC. In this context a better understanding of different influencing factors, such as sorption, swelling or surface activity is necessary together with a detailed characterization of different stages of crack propagation and underlying mechanisms. Therefor well-established testing methods, such as the Full Notch Creep Test (FNCT), were complemented by detailed fracture surface analysis using e.g. LSM and SEM in combination with a time-dependent optical monitoring of the progressing crack growth. For the crack growth also the ratio of fibrillated craze zone to crack opening is important for the deeper understanding of crack propagation and related material parameters which can be additionally addressed by X-ray computed tomography. T2 - 34th Polymer Degradation Disscussion Group (PDDG) Conference CY - Dubrovnik, Croatia DA - 12.06.2023 KW - Polyethylen KW - Full Notch Creep Test KW - Environmental Stress Cracking KW - Fracture Surface Analysis PY - 2023 AN - OPUS4-57711 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Pittner, Andreas A1 - Winterkorn, René A1 - Fabry, Çağtay A1 - Rethmeier, Michael A1 - Thiele, Marc A1 - Baeßler, Matthias A1 - Brauser, S. T1 - SmartWeld - Leichtbautechnik für Tragstrukturen von Offshore Windenergieanlagen N2 - Die Anwendung von Leichtbauprinzipien im Stahlbau, wie z.B. die Verwendung von aufgelösten Tragstrukturen, sog. Jackets-Fundamenten, bietet ein großes Potential zur Reduzierung des Ressourcenverbrauchs, insbesondere im Hinblick auf die benötigte Stahlmenge. In diesem Vortrag zeigen wir die Potenziale einer vollständigen Digitalisierung der schweißtechnischen Fertigungs- und Prüfkette auf, um eine vollautomatische Fertigung sowie Qualitätsprüfung von Rohrknoten als Schlüsselelement von Jackets-Fundamenten zu ermöglichen. Darüber hinaus wird der Zusammenhang zwischen der Geometrie der Nahtform und der resultierenden Ermüdungsfestigkeit durch numerische Methoden unter Einbeziehung bionischer Prinzipien bewertet. Es wird gezeigt, dass Hohlprofilknoten vollautomatisch unter Berücksichtigung von Geometrietoleranzen geschweißt werden können. Darüber hinaus konnte die Nahtform gemäß den numerischen Modellen hergestellt werden, was ein großes Potenzial für eine verlängerte Lebensdauer bietet. Anschließend werden die Verbesserungen bei der Ressourceneffizienz und die Reduzierung der Kohlendioxidemissionen durch eine Lebenszyklusanalyse bewertet. T2 - 11. Zukunftskonferenz Wind & Maritim CY - Rostock, Germany DA - 01.09.2022 KW - Offshore Windenergieanlagen KW - Gründungsstrukturen KW - Leichtbauprinzipien KW - Automatisierte Fertigung PY - 2022 AN - OPUS4-56654 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Pittner, Andreas A1 - Winterkorn, René A1 - Fabry, Çağtay A1 - Rethmeier, Michael A1 - Ratkovac, Mirjana A1 - Thiele, Marc A1 - Baeßler, Matthias T1 - Innovative Design- und Fertigungsstrategien zur Steigerung der Leichtbaupotenziale im Stahlbau N2 - Ziel des Verbundvorhabens „SmartWeld“ ist es, für die schweißtechnische Fertigung von Stahlbaustrukturen exemplarisch am Beispiel von Hohlprofilknoten, welche als designrelevante Elemente von Gründungsstrukturen für Offshore-Windenergieanlagen (OWEA) einsetzbar sind, die Möglichkeiten des Leichtbaus unter konsequenter Digitalisierung der Fertigungskette aufzuzeigen, um einerseits die Ressourceneffizienz zu forcieren und gleichzeitig wettbewerbsfähige Fertigungsstrategien aufzuzeigen. Innerhalb von „SmartWeld“ werden daher die Möglichkeiten einer wirtschaftlichen Fertigung von Leichtbau-Gründungsstrukturen am Beispiel aufgelöster Tragstrukturen (Jackets) aufgezeigt. Eine lastgerechte Auslegung der Schweißverbindungen nach bionischen Prinzipien ermöglicht, weitere Einsparpotenziale an Ressourcen bei gleichzeitiger Erhöhung der Lebensdauer zu erschließen. Die Ausnutzung konstruktiver Prinzipien des Leichtbaus zur Erzeugung innovativer und ressourcenschonender Produkte erfordert den Einsatz digitaler Werkzeuge in der Designphase, der virtuellen Absicherung, der Fertigung und Qualitätsüberwachung sowie nachgelagerten Bauteilprüfung zur Abbildung der Nutzungsphase. Im Rahmen der Arbeiten wird daher der gesamte Produktentstehungs- und Prüfprozess betrachtet. Dies beinhaltet das Design im Kontext des konstruktiven Leichtbaus, den schweißtechnischen Fertigungsprozess, die Bauteilprüfung sowie den Transfer der Ergebnisse in die Industrie durch serientaugliche Demonstratoren. Der Fokus der Arbeiten ist, die Fertigung auch im Umfeld eines für großskalige Stahlstrukturen üblichen hohen Individualisierungsgrades schweißtechnisch zu automatisieren und das Leichtbaupotenzial gezielt umzusetzen. Die Vorgaben aus der Designphase hinsichtlich einer lastgerechten Gestaltung bzw. Implementierung bionischer Ansätze können so gezielt durch einen adaptiven, automatisierten Schweißprozess eingestellt werden. Dies führt zu einer Erhöhung der Ermüdungs¬festigkeit und damit Produktlebensdauer, wodurch die Strukturen dünnwandiger ausgeführt und Ressourcen sowie CO2 eingespart werden können. T2 - Sitzung des DVS Fachausschuss FA03 - Lichtbogenschweißen CY - Rostock, Germany DA - 11.10.2022 KW - Offshore Windenergieanlagen KW - Gründungsstrukturen KW - Leichtbau KW - Automatisierte schweißtechnische Fertigung PY - 2022 AN - OPUS4-56656 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Pittner, Andreas A1 - Winterkorn, René A1 - Fabry, Çağtay A1 - Rethmeier, Michael A1 - Ratkovac, Mirjana A1 - Thiele, Marc A1 - Baeßler, Matthias T1 - Innovative Design- und Fertigungsstrategien zur Steigerung der Leichtbaupotenziale im Stahlbau N2 - Offshore wind energy plays an important role for the desired transition towards a carbon dioxide free industry within the next decades. However, the grounding of the offshore wind plants governs the overall installation process besides bureaucratic bottlenecks. The application of lightweight principles in steel construction, e.g. the usage dissolved load-bearing structures, so called Jackets foundations, offer great potential in reducing the resource consumption, especially with respect to the needed amount of steel. In this context this presentation focuses on a fully digitalization of the welding manufacturing and as well as testing chain to enable a fully automated manufacturing as well as quality assessment of tubular nodes as key element of Jackets foundation structures. Furthermore, the relationship between the seam shape geometry and resulting fatigue strength is evaluated by numerical methods incorporating bionic principles. It is shown that tubular nodes can be welded fully automatically taking geometry tolerances into account. Moreover, the seam shape could be manufactured as requested by the numerical models which offers great potential for an extended lifetime. Subsequently, the improvements in resource efficiency and reduction of carbon dioxide emissions are evaluated by a life-cycle-assessment. T2 - Leichtbau in der Hauptstadtregion - Rohstoffe - Recycling - Rohstoffe: Kreislaufwirtschaft im Leichtbau CY - Berlin, Germany DA - 28.11.2022 KW - Offshore Windenergie KW - Gründungsstrukturen KW - Leichtbau KW - Automatisierte schweißtechnische Fertigung PY - 2022 AN - OPUS4-56657 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Pittner, Andreas A1 - Winterkorn, René A1 - Fabry, Çağtay A1 - Rethmeier, Michael A1 - Ratkovac, Mirjana A1 - Thiele, Marc A1 - Baeßler, Matthias T1 - Innovative Design- und Fertigungsstrategien zur Steigerung der Leichtbaupotenziale im Stahlbau N2 - Ziel des Verbundvorhabens „SmartWeld“ ist es, für die schweißtechnische Fertigung von Stahlbaustrukturen exemplarisch am Beispiel von Hohlprofilknoten, welche als designrelevante Elemente von Gründungsstrukturen für Offshore-Windenergieanlagen (OWEA) einsetzbar sind, die Möglichkeiten des Leichtbaus unter konsequenter Digitalisierung der Fertigungskette aufzuzeigen, um einerseits die Ressourceneffizienz zu forcieren und gleichzeitig wettbewerbsfähige Fertigungsstrategien aufzuzeigen. Innerhalb von „SmartWeld“ werden daher die Möglichkeiten einer wirtschaftlichen Fertigung von Leichtbau-Gründungsstrukturen am Beispiel aufgelöster Tragstrukturen (Jackets) aufgezeigt. Eine lastgerechte Auslegung der Schweißverbindungen nach bionischen Prinzipien ermöglicht, weitere Einsparpotenziale an Ressourcen bei gleichzeitiger Erhöhung der Lebensdauer zu erschließen. Die Ausnutzung konstruktiver Prinzipien des Leichtbaus zur Erzeugung innovativer und ressourcenschonender Produkte erfordert den Einsatz digitaler Werkzeuge in der Designphase, der virtuellen Absicherung, der Fertigung und Qualitätsüberwachung sowie nachgelagerten Bauteilprüfung zur Abbildung der Nutzungsphase. Im Rahmen der Arbeiten wird daher der gesamte Produktentstehungs- und Prüfprozess betrachtet. Dies beinhaltet das Design im Kontext des konstruktiven Leichtbaus, den schweißtechnischen Fertigungsprozess, die Bauteilprüfung sowie den Transfer der Ergebnisse in die Industrie durch serientaugliche Demonstratoren. Der Fokus der Arbeiten ist, die Fertigung auch im Umfeld eines für großskalige Stahlstrukturen üblichen hohen Individualisierungsgrades schweißtechnisch zu automatisieren und das Leichtbaupotenzial gezielt umzusetzen. Die Vorgaben aus der Designphase hinsichtlich einer lastgerechten Gestaltung bzw. Implementierung bionischer Ansätze können so gezielt durch einen adaptiven, automatisierten Schweißprozess eingestellt werden. Dies führt zu einer Erhöhung der Ermüdungs¬festigkeit und damit Produktlebensdauer, wodurch die Strukturen dünnwandiger ausgeführt und Ressourcen sowie CO2 eingespart werden können. T2 - 9. Forum Leichtbau - Fortschrittliche Fertigungstechnologien und Werkstoffe für den Klimaschutz CY - Berlin, Germany DA - 29.09.2022 KW - Offshore Windenergieanlagen KW - Gründungsstrukturen KW - Leichtbau KW - Bionik KW - Automatisierte schweißtechniche Fertigung PY - 2022 AN - OPUS4-56655 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Strobl, Dominic T1 - Reduced Order Model for Temperature Field Simulation of Wire Arc Additive Manufacturing with Domain Mapping N2 - Additive manufacturing (AM) has revolutionized the manufacturing industry, offering a new paradigm to produce complex geometries and parts with customized properties. Among the different AM techniques, the wire arc additive manufacturing (WAAM) process has gained significant attention due to its high deposition rate and low equipment cost. However, the process is characterized by a complex thermal history making it challenging to simulate it in real-time for online process control and optimization. In this context, a reduced order model (ROM) using the proper generalized decomposition (PGD) method [1] is proposed as a powerful tool to overcome the limitations of conventional numerical methods and enable the real-time simulation of the temperature field of WAAM processes. These simulations use a moving heat source leading to a hardly separable parametric problem, which is handled by applying a novel mapping approach [2]. This procedure makes it possible to create a simple separated representation of the model, which allows to simulate multiple layers. In this contribution, a PGD model is derived for the temperature field simulation of the WAAM process. A good agreement with a standard finite element method is shown. The reduced model is further used in a stochastic model parameter estimation using Bayesian inference, speeding up calibrations and ultimately leading to a calibrated real-time simulation. T2 - MORTech 2023 - 6th International Workshop on Model Reduction Techniques CY - Paris, France DA - 22.11.2023 KW - Wire arc additive manufacturing KW - Reduced order modelling PY - 2023 AN - OPUS4-59105 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Niederleithinger, Ernst A1 - Hille, Falk A1 - Hofmann, Detlev A1 - Kind, Thomas ED - Isecke, B. ED - Krieger, J. T1 - Überwachung der Brücke Altstädter Bahnhof, Brandenburg./H. Begleituntersuchungen mit moderner Sensorik und zerstörungsfreier Prüfung N2 - Die B1 Brücke am Altstädter Bahnhof in Brandenburg an der Havel wurde im Dezember 2019 aufgrund von während einer turnusmäßigen Inspektion entdeckten Rissen und Hohlstellen entlang der vorgespannten Längsträger gesperrt und im Mai 2021 abgebrochen. In der Zwischenzeit wurde die Brücke detailliert überwacht. Vor dem Abriss wurden zudem umfangreiche Untersuchungen zur Bestandsaufnahme und Schadensanalyse sowie Tests moderner Sensorik vorgenommen. Dabei konnte sowohl die richtige, zuvor nicht sicher bekannte Anzahl von Spanngliedern in den Querträgern sicher ermittelt werden als auch durch moderne Varianten der Schwingungsmessungen und der faseroptischen Sensorik zusätzliche Kenntnisse püber das Bauwerksverhalten ermittelt werden . In dem Beitrag werden die Verfahren mit ihren Möglichkeiten und Grenzen vorgestellt, die Ergebnissee an der Brücke in Brandenburg erläutert und zukünftige Einsatzmöglichkeiten diskutiert. T2 - 5. Brückenkolloquium CY - Ostfildern, Germany DA - 06.09.2022 KW - Monitoring KW - Brücke KW - Radar KW - Vibration KW - Faseroptik PY - 2022 SN - 978-3-8169-3549-0 SP - 555 EP - 566 PB - Expert Verlag CY - Tübingen AN - OPUS4-55627 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Niederleithinger, Ernst T1 - Überwachung der Brücke Altstädter Bahnhof, Branden-burg./H. N2 - Die B1 Brücke am Altstädter Bahnhof in Brandenburg an der Havel wurde im Dezember 2019 aufgrund von während einer turnusmäßigen Inspektion entdeckten Rissen und Hohlstellen entlang der vorgespannten Längsträger gesperrt und im Mai 2021 abgebrochen. In der Zwischenzeit wurde die Brücke detailliert überwacht. Vor dem Abriss wurden zudem umfangreiche Untersuchungen zur Bestandsaufnahme und Schadensanalyse sowie Tests moderner Sensorik vorgenommen. Dabei konnte sowohl die richtige, zuvor nicht sicher bekannte Anzahl von Spanngliedern in den Querträgern sicher ermittelt werden als auch durch moderne Varianten der Schwingungsmessungen und der faseroptischen Sensorik zusätzliche Kenntnisse püber das Bauwerksverhalten ermittelt werden . In dem Beitrag werden die Verfahren mit ihren Möglichkeiten und Grenzen vorgestellt, die Ergebnissee an der Brücke in Brandenburg erläutert und zukünftige Einsatzmöglichkeiten diskutiert. T2 - 5. Brückenkolloquium CY - Ostfildern, Germany DA - 06.09.2022 KW - Monitoring KW - Brücke KW - Radar KW - Vibration KW - Faseroptik PY - 2022 AN - OPUS4-55628 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Eggert, Lara T1 - Korrosionsuntersuchungen im maritimen Bereich N2 - Im Rahmen des Projektes H2Mare wurden verschiedene küstennahe sowie offshore Standorte beprobt, um die tatsächliche Korrosivität der Atmosphären zu bestimmen. Mit Offshore Auslagerungsversuchen auf einer Technikplattform (freibewitterter und überdachter Bereich) und an Windenergieanlagen (Außen- und Innenbereich), sollten Daten zur Korrosivität ermittelt werden. Diese stellen eine Grundlage für die dauerhafte und gleichzeitige wirtschaftliche Auslegung des Korrosionsschutzes für Offshore-Prozessanlagen dar. Neben den Korrosivitätsinformationen liefern die Auslagerungsversuche auch Informationen über die Performance typischer Konstruktionsmaterialien im Offshore Bereich, wie etwa nichtrostender Stähle sowie ausgewählter Korrosionsschutzmaßnahmen. Der Beitrag stellt ausgewählte Ergebnisse der Auslagerungskampagnen vor. T2 - H2Mare-Abschlusskonferenz CY - Rostock, Germany DA - 23.09.2025 KW - Atmosphärische Korrosion KW - Spaltkorrosion bei nichtrostenden Stählen KW - Reparaturbeschichtungen PY - 2025 AN - OPUS4-64236 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Eggert, Lara T1 - Offshore-Reparaturbeschichtungen mit Chloridvorbelastung N2 - Bei maritimen Reparaturbeschichtungen ist eine chloridfreie Oberfläche nicht immer zu gewährleisten. Zur Untersuchung des Einflusses chloridhaltiger Verunreinigungen auf die Schutzwirkung maritimer Epoxid-Reparaturbeschichtungen wurden gestrahlte Stahlproben (Sa 2½) mit künstlichem Meerwasser besprüht. So entstanden drei Verunreinigungszustände: sauber (C0), leicht verunreinigt (C1) und stark verunreinigt (C2). Zwei Beschichtungen (A1 und A2) wurden appliziert und durch Ritzen und Impact-Schäden zusätzlich beansprucht. T2 - H2Mare-Abschlusskonferenz CY - Rostock, Germany DA - 23.09.2025 KW - Reperaturbeschichtung KW - Maritime Korrosion KW - Wechselzyklustest PY - 2025 AN - OPUS4-64235 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ebell, Gino T1 - Elektrochemische Messungen N2 - Durch das alkalische Milieu des Porenwassers im Beton ist der Stahl normalerweise dauerhaft vor Korrosion geschützt. Unter ungünstigen Umgebungsbedingungen (Chlorideintrag, Carbonatisierung) kann die passive Deckschicht auf der Stahloberfläche zerstört werden. Der Korrosionsprozess ist initiiert. Die entstehenden Korrosionsprodukte werden zunächst vom Porengefüge des Betons aufgenommen, ohne dass es zu sichtbaren Schäden am Bauwerk führt. Im fortgeschrittenem Stadium der Korrosion können sich dann Risse und Abplatzungen bilden. Um notwendige Sanierungsmaßnahmen sowohl aus sicherheitstechnischen Gründen als auch aus wirtschaftlichen Erwägungen rechtzeitig einzuleiten, sind frühzeitige und weitestgehend zerstörungsfreie Prüfverfahren zur Ermittlung der aktuellen Korrosionswahrscheinlichkeit der Stahlbewehrung von großer Bedeutung. Deshalb finden Methoden und Verfahren zur laufenden bzw. regelmäßigen Korrosionsüberwachung von Stahlbetonbauwerken ständig größere Beachtung, sowohl im Bereich Forschung und Entwicklung als auch in der Praxis. Die elektrochemische Potentialfeldmessung ist ein etabliertes und weit verbreitetes Verfahren zur Beurteilung des Korrosionszustandes der Bewehrung in Stahlbetonbauwerken. Mit Hilfe dieses Verfahrens können Bereiche korrodierender Bewehrung zerstörungsfrei lokalisiert werden. In der Regel kommt diese Methode bei der Detektion von chloridinduzierter Korrosion zum Einsatz. Der Lehrgang vermittelt den Teilnehmenden in kompakter Form einen zusammenfassenden Überblick über die notwendigen Grundlagen zum Verständnis der Messmethode, der Vorbereitung und Durchführung der Messungen, der notwendigen Begleituntersuchungen sowie der Interpretation der gewonnenen Daten. Der erste Tag ist der theoretischen Ausbildung gewidmet, am zweiten Tag folgt dann die praktische Anwendung der Lerninhalte. Am dritten Tag folgt die Abnahme der praktischen und theoretischen Prüfung zur Erlangung des Sachkundenachweises. T2 - Sachkundelehrgang zur Durchführung von Potentialfeldmessungen CY - Berlin, Germany DA - 24.04.2023 KW - Potentialfeldmessung KW - Korrosion PY - 2023 AN - OPUS4-57494 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ebell, Gino T1 - Potentialfeldmessung in Theorie und Praxis N2 - Durch das alkalische Porenwassermilieu ist Stahl im Beton vor Korrosion geschützt. Unter ungünstigen Umgebungsbedingungen (Karbonatisierung, Chlorideintrag) kann die passive Deckschicht auf der Stahloberfläche zerstört werden. Im weiteren Verlauf können sich korrosionsbedingte Folgeschäden, wie Risse und Abplatzungen am Bauwerk ergeben. Um notwendige Sanierungsmaßnahmen sind frühzeitige und weitgehend zerstörungsfrei ermittelte Informationen über das aktuelle Korrosionsverhalten der Stahlbewehrung von großer Bedeutung. Die Potentialfeldmessung ist ein etabliertes und weit verbreitetes Verfahren zur Beurteilung des Korrosionszustandes der Bewehrung in Stahlbetonbauwerken. Mit Hilfe dieses Verfahrens können Bereiche aktiv korrodierender Bewehrung zerstörungsfrei lokalisiert werden. In der Regel kommt diese Messmethode bei der Detektion chloridinduzierter Korrosion zum Einsatz T2 - Vorlesung TU-Berlin CY - Berlin, Germany DA - 30.06.2022 KW - Korrosion KW - Potentialfeldmessung PY - 2022 AN - OPUS4-55156 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ebell, Gino T1 - Dauerhaftigkeit von Zink an verschiedenen küstennahen Standorten N2 - Die Korrosionsbeständigkeit metallener Werkstoffe ist von der Korrosivität der einwirkenden Medien abhängig. Für ein feuerverzinktes Stahlbauteil ist die Art der atmosphärischen Exposition (frei bewittert, überdacht) und die standortabhängige Korrosivität der Atmosphäre maßgebend für die mögliche Nutzungsdauer. Die Bestimmung der Korrosivität der Atmosphäre an einem Standort erfolgt durch Auslagerung von Probenblechen verschiedener Werkstoffe. Gemäß DIN EN ISO 9226 werden Zink, Kupfer, Aluminium und Stahlbleche ausgelagert, dabei wird die Korrosivität der Atmosphäre an einem Standort nach DIN EN ISO 9223 über den Masseverlust der Probenbleche nach einem Jahr Auslagerung bestimmt. Die Korrosivität an einem Standort ist für jeden Werkstoff zu ermitteln und gesondert zu betrachten. In diesem Vortrag werden verschiedene küstennahe Auslagerungsstandorte und deren Korrosivität dargestellt, sowie die aus der Anwendung der DIN EN ISO 9224 ableitbaren Entwicklung der Korrosionsraten. Der Korrosionsschutz durch Feuerverzinken von Bauteilen kann in maritimer Exposition unter heutigen atmosphärischen Bedingungen durchaus Nutzungsdauern > 50 Jahre realisieren. T2 - Korrosionsschutz in der maritimen Technik CY - Hamburg, Germany DA - 29.01.2025 KW - Korrosion PY - 2025 AN - OPUS4-62508 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Zekhnini, Khalid T1 - Constructive corrosion protection - Stainless steel in offshore plant construction N2 - Maritime exposure poses particular challenges for corrosion protection in plant construction. In addition to the right choice of materials, special design features that can have an impact on corrosion resistance must also be taken into account to ensure long-lasting corrosion protection. In practice, structural crevice arrangements are unavoidable, and therefore the crevice corrosion resistances of stainless steels are of particular importance. These and other influences are being investigated in this joint project. T2 - H2Mare PtX-Verbundtreffen CY - Hamburg, Germany DA - 16.04.2024 KW - Atmospheric Corrosion KW - Offshore KW - Corrosion Testing KW - Marine Corrosion KW - Stainless steel KW - Crevice corrosion PY - 2024 AN - OPUS4-59918 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ebell, Gino T1 - Corrosivity of Atmospheres and the Resulting Corrosion Protection of Galvanized Steel N2 - The investigation of the corrosivity of atmospheres are major target to ensure the durability of metallic structures. Therefore the corrosivity has to be determined and finally, the right material or corrosion protection system has to be chosen. T2 - Intergavla CY - Brussels, Belgium DA - 10.06.2024 KW - Corrosion KW - Potentialfeldmessung KW - Atmospheric corrosion PY - 2024 AN - OPUS4-60591 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Wachtendorf, Volker T1 - Maßgeschneiderte künstliche Bewitterungstests zur Untersuchung der alterungsbedingten Freisetzung von Produkten in die Umwelt N2 - Genormte künstliche Bewitterungstests sind häufig nicht spezifisch für die Anwendungssituation oder das Material. Das macht die Entwicklung spezifischer Tests erforderlich. Für deren Entwicklung müssen Maximalparameter der Anwendungssituation bekannt sein, womit dann der künstliche Test formuliert wird und dessen Bedingungen werden dann solange optimiert, bis die Korrelation der Effekte von natürlichem und künstlichem Test ausreichend ist. Für Untersuchungen der Freisetzung kann der verbleibende Rest in der Probe und/oder die freigesetzte Menge in Luft, Boden, Wasser bestimmt werden. Im ersten Beispiel der Witterungswirkung wurde die Freisetzung von Kohlenstoff-Nanoröhrchen (CNT) aus Polymer-Kompositen untersucht (unter Verwendung von empfindlich-nachweisbarer radioaktiver 14C-Markierung für einzelne CNT-Partikel), in einem zweiten die Freisetzung von anorganischen und organischen Bestandteilen aus elastomeren Bestandteilen von Sportböden (Bahnen und Kunstrasen) in Wasser. T2 - SKZ-Tagung: Bewitterung van Kunststoffen CY - Würzburg, Germany DA - 06.07.2022 KW - Künstliche Bewitterung KW - UV KW - Degradation KW - Freisetzung KW - CNT KW - Carbo-Nanotubes KW - Composite KW - Nano-Partikel KW - 14C-Markierung KW - Sportböden KW - Kunstrasen KW - Grundwasser PY - 2022 AN - OPUS4-55219 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Braun, Ulrike T1 - Elastomere und TPE – Gut für die Umwelt? – Kreislaufwirtschaft und Normung vereinen N2 - Der Vortrag fasst Projekte an der BAM mit Hinblick auf Elastomere und Umweltthemen zusammen. T2 - DIN Workshop: Elastomere und TPE – Gut für die Umwelt? – Kreislaufwirtschaft und Normung vereinen CY - Berlin, Germany DA - 08.08.2019 KW - Mikroplastik KW - Reifenabrieb KW - Sportböden PY - 2019 AN - OPUS4-49064 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Ciornii, Dmitri A1 - Hodoroaba, Vasile-Dan A1 - Wachtendorf, Volker A1 - Fengler, Petra A1 - Altmann, Korinna T1 - Interlaboratory Comparison Reveals State of the Art in Microplastic Detection and Quantification Methods N2 - In this study, we investigate the current accuracy of widely used microplastic (MP) detection methods through an interlaboratory comparison (ILC) involving ISO-approved techniques. The ILC was organized under the prestandardization platform of VAMAS (Versailles Project on Advanced Materials and Standards) and gathered a large number (84) of analytical laboratories across the globe. The aim of this ILC was (i) to test and to compare two thermo-analytical and three spectroscopical methods with respect to their suitability to identify and quantify microplastics in a water-soluble matrix and (ii) to test the suitability of the microplastic test materials to be used in ILCs. Two reference materials (RMs), polyethylene terephthalate (PET) and polyethylene (PE) as powders with rough size ranges between 10 and 200 μm, were used to press tablets for the ILC. The following parameters had to be assessed: polymer identity, mass fraction, particle number concentration, and particle size distribution. The reproducibility, SR, in thermo-analytical experiments ranged from 62%−117% (for PE) and 45.9%−62% (for PET). In spectroscopical experiments, the SR varied between 121% and 129% (for PE) and 64% and 70% (for PET). Tablet dissolution turned out to be a very challenging step and should be optimized. Based on the knowledge gained, development of guidance for improved tablet filtration is in progress. Further, in this study, we discuss the main sources of uncertainties that need to be considered and minimized for preparation of standardized protocols for future measurements with higher accuracy. KW - Microplastics KW - Interlaboratory comparison KW - PlasticsFatE KW - PET KW - PE KW - Reference materials KW - VAMAS KW - Thermo-analytical methods KW - Spectroscopical methods PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-630462 DO - https://doi.org/10.1021/acs.analchem.4c05403 SN - 1520-6882 VL - 97 SP - 8719 EP - 8728 PB - ACS Publications AN - OPUS4-63046 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF ED - Ebell, Gino T1 - Sammelmappe zum Sachkundelehrgang zur Durchführung von Potentialfeldmessungen 2022 N2 - Die Sammelmappe umfasst alle Lehrinhalte für den Sachkundelehrgang zur Durchführung von Potentialfeldmessungen 2022, der vom 16. bis 18.05.2022 in Baruth/Mark stattgefunden hat. T2 - Sachkundelehrgang zur Durchführung von Potentialfeldmessungen 2022 CY - Baruth/Mark, Germany DA - 16.05.2022 KW - Korrosion KW - Potentialfeldmessung PY - 2022 SP - 1 EP - 82 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-54873 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - RPRT A1 - Babutzka, Martin A1 - Zekhnini, Khalid A1 - Seifert, Lando A1 - Le, Quynh Hoa A1 - Grabowski, Sven T1 - Schlussbericht zum Forschungsvorhaben „Verbundvorhaben: "KKS-Gründung" - Korrosionsmonitoring und aktiver kathodischer Korrosionsschutz von Offshore-Gründungsstrukturen - Teilvorhaben: Korrosionsprüfungen im Laborcontainer“ in der Fördermaßnahme „Anwendungsorientierte nichtnukleare FuE im 6. Energieforschungsprogramm“ im Förderbereich „Windenergie“ N2 - Das Ziel des Verbundforschungsvorhabens KKS-Gründung war die Entwicklung eines Monitoringsystems zur Erfassung von Korrosion an Gründungsstrukturen im Labormaßstab. Dafür war eine umfassende Bewertung und Beschreibung korrosionsbeeinflussender Faktoren und der Korrosionssysteme notwendig. Im Vorhaben KKS-Gründung wurde die Gründungsstruktur unterhalb der Wasserlinie betrachtet bis hin zum anaeroben Bereich im Sediment. Insbesondere der Sedimentbereich wurde bisher nur unzureichend betrachtet. Da die komplexen Mechanismen in der Sedimentzone noch nicht ausreichend wissenschaftlich untersucht wurden, mussten Möglichkeiten entwickelt werden, um diese zu bewerten. Im Verbundforschungsvorhaben KKS-Gründung agierte die Bundesanstalt für Materialforschung und -prüfung (BAM) als Forschungsstelle. Die Hauptziele des Teilvorhabens der BAM waren die Bereitstellung einer Messumgebung für das von den Partnern entwickelte Monitoringsystem, die umfassende wissenschaftliche Beschreibung der Korrosionssysteme im Unterwasserbereich und Sediment sowie die Gewinnung von Messdaten zur Verifizierung und Überführung in die Simulation. Als Forschungsstelle war die BAM der Ansprechpartner für die Verbundpartner bei wissenschaftlichen Fragestellungen. Die Hauptziele des Vorhabens wurden erreicht und es wurden grundlegende Erkenntnisse zum Korrosionsverhalten von Offshore-Stahl im Unterwasser und Sedimentbereich gewonnen. Darüber hinaus wurden wichtige Erkenntnisse zum Betrieb eines Laborcontainers und zur Nachstellung von Korrosionssystemen in Meerwasserbecken bei Verwendung von künstlichem Meerwasser und Sand als Sediment gewonnen. Eine Beschreibung und Bewertung der Korrosivität und ablaufender Reaktionen in den einzelnen Belastungszonen wurde mittels elektrochemischer und gravimetrischer Verfahren vorgenommen. KW - Korrosionsschutz KW - KKS KW - Korrosionsmonitoring KW - Offshore-Windenergieanlagen KW - Meerwasser KW - Sediment PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-569252 SP - 1 EP - 74 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-56925 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Müller, Thoralf T1 - Korrosion und Korrosionsschutzverfahren: Teil 1 Grundlagern der Korrosion metallener Werkstoffe N2 - Der Übersichtsvortrag vermittelt Kenntnisse zu den Grundlagen der Korrosion metallischer Werkstoffe für das KKS Grundlagenseminar für erdverlegte Anlagen und Stahlbetonbau zur Vorbereitung auf die Zertifikatsprüfung DIN EN 15257. Diese Kenntnisse bilden die Grundlage zum Verständnis der Beeinflussung von Korrosionssystemen durch die Anwendung kathodischer Schutzmaßnahme T2 - Fachausbildung Kathodischer Korrosionsschutz - Grundlagenkurs für erdverlegte Anlagen, Stahlbeton und Innenschutz CY - Online meeting DA - 14.02.2024 KW - Korrosion KW - Atmosphäre KW - Passivität KW - Stahl KW - Nichtrostender Stahl PY - 2024 AN - OPUS4-59531 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Ebell, Gino A1 - Seifert, Lando A1 - Burkert, Andreas T1 - Innovative Korrosionsprüfung für Beton- und Spannstähle T1 - Test methods for corrosion testing of reinforcing and prestressing steels N2 - Korrosion ist einer der maßgeblichen Schädigungsmechanis-men im Stahlbetonbau und limitiert die Nutzungsdauer vonInfrastrukturbauwerken zum Teil erheblich. Dabei differenziertman zwischen verschiedenen Korrosionsvarianten, Korrosioninfolge Karbonatisierung des Betons, chloridinduzierte Korro-sion an Meerwasserbauwerken oder durch Tausalzbelastungund im Fall von Spannstahlbauwerken kann zusätzlich was-serstoffinduzierte Spannungsrisskorrosion (SpRK) auftreten.Für den Einsatz alternativer Betonstähle wie nichtrostenderBetonstahl gilt es, die Höhe des kritischen korrosionsaus-lösenden Chloridgehalts zu bestimmen. Um diesen für diejeweiligen Betonstähle zu ermitteln, fehlen bislang jedochnormativ geregelte Prüfverfahren. Die Empfindlichkeit vonSpannstählen gegenüber SpRK bedarf gemäß aktueller Nor-mung Langzeit-Auslagerungstests, die eine werkseigeneProduktionskontrolle aufgrund der langen Prüfzeiten nahezuunmöglich machen. Ein neu entwickeltes Prüfverfahren unterAnwendung kathodischer Polarisation, das inzwischen imneusten Entwurf der DIN EN ISO 15630–3 aufgenommenwurde, ermöglicht eine Bewertung der SpRK-Empfindlichkeitfür Spanndrähte innerhalb von 24 Stunden. Die Ergebnissetragen zur Verbesserung der Lebensdauerabschätzung undzur Weiterentwicklung von Normen für korrosionsbeständigeBetonstähle und der Robustheitsbewertung von Spannstählenbei. N2 - Corrosion is a primary damage mechanism in reinforced concrete construction, significantly reducing the service life of infrastructure. A categorisation of corrosion is imperative for the comprehension of the subject. The corrosion of concrete can be attributed to the carbonation process, whilst chloride-induced corrosion is prevalent in structures exposed to seawater or by de-icing salt. Additionaly to the former corrosion processe, prestressing steel structures could be also highly susceptible to hydrogen-induced stress corrosion cracking (SCC). In order to utilise alternative reinforcing steels, such as stainless reinforcing steel, it is necessary to ascertain the level of critical chloride threshold that can induce corrosion. Nevertheless, there is an absence of standardised test methods for determining this for the respective reinforcing steels to date. Acc. to current standardization, the sensitivity of prestressing steels to chromium content necessitates long-term ageing tests, which impede in-house production control due to the extended testing times. However, a newly developed test method using cathodic polarization, which has now been included in the latest draft of DIN EN ISO 15630–3, makes it possible to assess the susceptibility of prestressing steels to corrosion cracking within 24 hours. The results of this study will contribute to the improvement of service life estimation and the further development of standards for corrosion-resistant reinforcing steels and the robustness assessment of prestressing steels. KW - Korrosion KW - Spannstahl KW - Nichtrostender Betonstahl KW - Corrosion KW - Prestressing steel KW - Stainless reinforcing steel KW - Wasserstoff KW - Spannungsrisskorrosion KW - Lochkorrosion KW - Hydrogen KW - Stress corrosion cracking KW - Pitting corrosion PY - 2025 DO - https://doi.org/10.1002/best.202500025 SN - 0005-9900 SN - 1437-1006 SP - 1 EP - 8 PB - Ernst CY - Berlin AN - OPUS4-63305 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Haacke, Nasrin T1 - Runoff-Messungen zur Abschätzung der Dauerhaftigkeit von Materialien und des Eintrags von Schwermetallionen in die Umwelt N2 - Die Präsentation stellt das Runoff-Projekt in seiner Gesamtheit vor. Dabei liegt der Fokus vor allem auf die verschiedenen Untersuchungsverfahren zur Neubewertung der Dauerhaftigkeit von Dach- und Fassadenmaterialien. Dazu zählen elektrochemische Untersuchungen der Deckschichtstabilität, die Bestimmung der Korrosionsprodukte sowie des Massenverlustes und die Identifikation wichtiger Einflussfaktoren. T2 - 17. Sitzung des AK Korrosionsuntersuchung und -überprüfung CY - Dresden, Germany DA - 04.12.2023 KW - Runoff KW - Kupfer KW - Zink KW - Deschichtwiderstand KW - Dauerhaftigkeit KW - Schwermetalle PY - 2023 AN - OPUS4-59071 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Müller, Thoralf T1 - Korrosion und Korrosionsschutzverfahren: Teil 2 Korrosionsschutzverfahren N2 - Der Vortrag thematisiert die Grundlagen des Korrosionsschutzes. Dieser kann planungs-,werkstoff oder mediumsseitig erfolgen oder mit elektrochemischen Methoden umgesetzt werden. Der Vortrag beschreit die Korrosivitäten der Atmosphären und welche Maßnahmen für den Korrosionsschutz daraus abgeleitet werden können. T2 - Fachausbildung Kathodischer Korrosionsschutz - Grundlagenkurs für erdverlegte Anlagen, Stahlbeton und Innenschutz CY - Online meeting DA - 14.02.2024 KW - Korrosion KW - Nichtrostende Stähle KW - Passivität KW - Korrosionsschutz PY - 2024 AN - OPUS4-59530 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Tschirschwitz, Rico A1 - Krentel, Daniel A1 - Kluge, Martin A1 - Askar, Enis A1 - Habib, Abdel Karim A1 - Kohlhoff, Harald A1 - Krüger, Simone A1 - Neumann, Patrick P. A1 - Rudolph, Miachael A1 - Schoppa, André A1 - Storm, Sven-Uwe A1 - Szczepaniak, Mariusz ED - Aga, Diana ED - Daugulis, Andrew ED - Li Puma, Gianluca ED - Lyberatos, Gerasimos ED - Tay, Joo Hwa ED - Lima, Éder Claudio T1 - Hazards from failure of CNG automotive cylinders in fire N2 - Compressed natural gas (CNG) is a widely used automotive fuel in a variety of countries. In case of a vehicle fire where the safety device also malfunctions, a failure of the CNG automotive cylinder could occur. Such a cylinder failure is associated with severe hazards for the surrounding environment. Firstly, a comprehensive analysis is given below, summarizing various accidents involving CNG automotive cylinders and their consequences. In an extensive experimental program, 21 CNG automotive cylinders with no safety device were tested. Of the 21, burst tests were carried out on 5 Type III and 5 Type IV cylinders. Furthermore, fire tests with 8 Type III and 3 Type IV cylinders were conducted. Apart from cylinder pressure, inner temperature and cylinder mantle temperature, the periphery consequences, such as nearfield blast pressure and fragmentation are documented. The maximum measured overpressure due to a Type III cylinder failure was p = 0.41 bar. Each traceable fragment was georeferenced. All-in-all, fragment throw distances of d > 300 m could be observed. As one key result, it can be stated that the tested Type IV CNG cylinders showed less critical failure behavior then the Type III cylinders under fire impingement. KW - CNG KW - Composite cylinder KW - Gas cylinder KW - Tank failure KW - Fragments PY - 2019 DO - https://doi.org/10.1016/j.jhazmat.2018.12.026 SN - 0304-3894 SN - 1873-3336 VL - 367 SP - 1 EP - 7 PB - Elsevier CY - New York City, New York, USA AN - OPUS4-47135 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Gluth, Gregor T1 - Microbially induced corrosion of cementitious materials in sewer systems N2 - Sewer networks (also called wastewater systems) include structures to collect and transport wastewater to disposal or treatment in dedicated facilities. These networks are essential infrastructures of our societies, and the size of these systems in terms of length as well as asset value is usually vast. Accordingly, the annual rehabilitation and replacement costs for sewer networks are very high in many countries. In addition, failures of wastewater systems can cause severe health and environmental problems, making the durability of these infrastructures an issue of crucial societal importance. A substantial fraction of the deterioration of sewers is caused by microbially influenced corrosion (MIC) of concrete structures in the networks, and, thus, understanding the causes of this process is crucial to be able to effectively direct resources for rehabilitation, replacement and construction of sewer systems. Because of the importance of the problem, it has been studied for many decades, and significant progress has been made during this time. In recent years, answers to several previously underexplored questions, for example regarding the validity of the different test methods to assess the resistance of cementitious materials against MIC and the suitability of new cementitious materials for sewer repair, have begun to emerge. The present contribution gives an overview over the processes involved in MIC of cementitious materials in sewers, and reviews recent findings concerning the resistance of cementitious materials against MIC. The data indicate that alkali-activated materials can exhibit exceptionally high resistance against MIC, while it is presently not fully understood which mix design parameters deter¬mine this resistance. Disagreement exists in the literature regarding the causes of the generally high resistance of calcium aluminate cements. Significant progress has been made in determining the deterioration rate of cementitious materials under strongly corroding conditions, but well-founded approaches to classify the severity of MIC attack in sewers seem not to be available at present. T2 - MICxUS 2025 – Symposium on Microbiologically Influenced Corrosion (MIC) in Industrial and Utility Systems CY - Nicosia, Cyprus DA - 21.01.2025 KW - MIC KW - Cement KW - Repair mortar KW - Sulfuric acid KW - Sewers PY - 2025 AN - OPUS4-62738 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Baeßler, Matthias T1 - Introduction to the Workshop Life Time Extension N2 - The article introduces the topic of life time extension for offshore wind turbines. On the one hand, analogies are drawn with the topic of old steel bridges. On the other hand, potential regulatory issues and minimum requirements are discussed. T2 - Workshop Offshore Wind CY - Berlin, Germany DA - 26.02.2025 KW - Life Time Extension KW - Offshore Wind PY - 2025 AN - OPUS4-62640 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kemmler, Samuel T1 - A Fluid Solid Coupled Micromechanical Simulation of Piping Erosion During the Installation of a Suction Bucket for the Foundation of an Offshore Wind Turbine N2 - We present our approach and methodology for simulating piping erosion, which occurs during the installation process of suction bucket foundations for offshore wind turbines. We show several simulations and analyze the hydrodynamic and contact forces acting on the granular fabric and the differential pressure of the fluid phase. We demonstrate weak scaling performance on the LUMI supercomputer with a parallel efficiency of up to 90% for 4096 Graphics Compute Dies. T2 - 9th European Congress on Computational Methods in Applied Sciences and Engineering (ECCOMAS) CY - Lisbon, Potugal DA - 03.06.2024 KW - Offshore wind turbine KW - Suction bucket KW - Coupled fluid-particle simulation KW - High-performance computing PY - 2024 AN - OPUS4-60207 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Zekhnini, Khalid A1 - Seifert, Lando T1 - Aspects of corrosion protection in the maritime sector– Focus of Current research of BAM for H2Mare N2 - Germany has set itself the task of becoming a world leader in the field of green hydrogen technologies and is promoting the transition to a hydrogen economy. The H2Mare flagship project is exploring the offshore production of green hydrogen and other power-to-X products. One of the most important goals is the safe and cost-efficient operation of offshore infrastructures, where a service life of at least 25 years is aimed at. However, the corrosive environment towards metallic materials presents challenges in marine areas. The atmosphere at one location could be affected by the distance to the sea level and does not have the same corrosivity for all exposed kinds of materials. The research of the durabilitty of different materials and corrosion protection systems by weathering campaigns and laboratory experiments aims to close this gap of knowledge. BAM‘s mandate is to make the data available to the responsible operators through standardisation to ensure safety and cost efficiency. T2 - H2Mare Conference 2024 CY - Berlin, Germany DA - 06.06.2024 KW - Atmospheric Corrosion KW - Offshore KW - Wind energy KW - Marine Corrosion KW - Laboratory Container KW - Corrosion protecting system KW - Sediment KW - Green Hydrogen PY - 2024 AN - OPUS4-60225 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Seifert, Lando T1 - Weathering campaigns for a marine corrosion atlas N2 - Germany has set itself the task to become a world leader in the field of green hydrogen technologies and is promoting the transition to a hydrogen economy. The H2Mare flagship project is exploring the offshore production of green hydrogen and other power-to-X products. One of the most important goals is the safe and cost-efficient operation of offshore infrastructures, where a service life of at least 25 years is aimed. However, the corrosive environment towards metallic materials presents challenges in marine areas. The atmosphere at one location could be affected by the distance to the sea level and does not have the same corrosivity for all exposed kinds of materials. The creation of an atmosphere corrosion atlas for marine environments by weathering campaigns aims to close this gap. Operators of offshore structures can use the data to estimate the corrosivity of the atmosphere on the construction site. This allows planning to be optimized in terms of platform safety as well as maintenance costs. T2 - Conference EUROCORR 2024 CY - Paris, France DA - 01.09.2024 KW - Offshore Corrosion KW - Marine Corrosion KW - Corrosivity KW - Green Hydrogen KW - Power-to-X PY - 2024 AN - OPUS4-60989 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kemmler, Samuel A1 - Cuéllar, Pablo A1 - Artinov, Antoni A1 - Luu, Li-Hua A1 - Farhat, Abbas A1 - Philippe, Pierre A1 - Rettinger, Christoph A1 - Köstler, Harald T1 - A fully-resolved micromechanical simulation of piping erosion during a suction bucket installation N2 - Granular fluidization phenomena such as piping erosion represent a challenge to the delicate installation process of offshore suction bucket foundations. A detailed analysis of the complex conditions in terms of soil composition, soil state, and foundation installation parameters that may lead to piping can be very demanding, if at all possible, solely by experimental means or using macroscopic continuum-based seabed models. The present paper presents a fully-resolved fluid-coupled micromechanical approach for a three-dimensional numerical simulation of the installation process of a suction bucket using the lattice Boltzmann method and discrete element method. The developed model is validated using well-established benchmarks and calibrated by means of experimental data from physical model tests on relevant scenarios focusing on the local fluidization of fixed embedded suction buckets as well as on the suction-driven installation of unrestrained buckets. The qualitative and quantitative agreement with the experimental data both endorse the proposed methodology and highlight the physical soundness of the obtained results. Thereby, the paper shows that three-dimensional analyses of relevant local scenarios at a real scale with little macromechanical model assumptions are feasible. KW - Micromechanical simulation KW - Fluid–solid coupling KW - Piping erosion KW - Suction bucket foundation KW - Offshore wind support structure KW - High-performance computing PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-633790 DO - https://doi.org/10.1016/j.compgeo.2025.107375 SN - 0266-352X VL - 186 SP - 1 EP - 17 PB - Elsevier B.V. AN - OPUS4-63379 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Rappsilber, Tim A1 - Krüger, Simone A1 - Raspe, Tina A1 - Wagner, Patrick A1 - Liebner, Christian A1 - Strzyz, Thaddeus A1 - Tschirschwitz, Rico T1 - Hazard classification of different lithium-ion battery types after triggering thermal runaway N2 - For a better understanding of relevant parameters influencing the thermal runaway, this work classifies the behavior of six different types of lithium-ion batteries. Based on 145 repeatable tests, this research has created a unique and detailed database of battery behavior during thermal runaway. It contains information about changes in cell temperature, voltage, mass loss, smoke gas release and gas pressure. When it comes to characterizing the thermal runaway behavior across different cell types, this work eliminates the need for complex meta-analyses, which can only provide limited information due to the different test conditions in different test benches. In a pressure-resistant 100 dm³ autoclave and an 8-m³ room with connected multi gas analysis, 24 setups were examined under identical conditions. The investigations were carried out as a function of the variation parameters cell geometry, cathode active material, state of charge and initiation method of thermal runaway. The analysis of the measurement data reveals clear differences in the thermal runaway behavior of the tested cell types and can be used as a reference for determining the hazard potential in individual assessment categories of different cells. All measured values from both test benches as well as the visual evaluation of the cell behavior during the test runs in the 8 m³ room are made available in a comprehensive data table in the supplementary material. KW - Lithium Ion KW - Thermal Runaway KW - State of charge KW - Hazard classification KW - gas emission PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-634429 DO - https://doi.org/10.1016/j.jlp.2025.105691 SN - 0950-4230 VL - 97 SP - 1 EP - 15 PB - Elsevier B.V. CY - Amsterdam AN - OPUS4-63442 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Lehmann, Jens T1 - Stahl mit Potenz(t)ial - Duplexstähle im Bauwesen N2 - Der Vortrag enthält eine Übersicht über die gemeinsame Zusammenarbeit der BAM mit Fa. Modersohn der letzten 20 Jahre. Der Fokus liegt dabei auf den Lean Duplex Stählen. T2 - 50 Jahre Modersohn Jubiläumsveranstaltung - Teil 2 Handelspartner CY - Spenge, Germany DA - 17.06.2023 KW - Korrosion KW - Nichtrostender Stahl KW - KorroPad KW - Auslagerungsversuche KW - Lean Duplex PY - 2023 AN - OPUS4-57818 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Lehmann, Jens T1 - Stahl mit Potenz(t)ial - Duplexstähle im Bauwesen N2 - In diesem Vortrag wird eine Übersicht der gemeinsamen Zusammenarbeit von BAM und Modersohn gegeben. Der Fokus liegt auf dem Thema Duplexstahl. T2 - 50 Jahre Modersohn Jubiläumsveranstaltung - Teil 1 Industriepartner CY - Spenge, Germany DA - 16.06.2023 KW - Korrosion KW - Nichtrostender Stahl KW - KorroPad KW - Auslagerungsversuche KW - Lean Duplex PY - 2023 AN - OPUS4-57817 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Balscheit, Hagen T1 - Experimental Investigation on Buckling Behavior of soil-embedded Piles N2 - Monopile-Gründungen sind die mit Abstand am häufigsten verwendete Gründungskonstruktion für Offshore-Windenergieanlagen. Ein wesentliches Problem bei der Bemessung ist das lokale Beulen des Gründungspfahls, welches typischerweise im Bereich der Bettung auftritt. Aufgrund der Nichtlinearität der Bettungsrandbedingung sind klassische Bemessungsansätze nicht anwendbar, so dass der Bemessungsingenieur auf eine vollständig numerische Berechnung zurückgreifen muss. In diesem Vortrag wird eine experimentelle Versuchskampagne zur Erzeugung von Kalibrierungsdaten für solche numerischen Modelle vorgestellt. Eine ausführlichere Darstellung findet sich im gleichnamigen Artikel. T2 - EUROSTEEL 2023 CY - Amsterdam, Netherlands DA - 11.09.2023 KW - Wind KW - Wind Energy KW - Offshore KW - Shell Buckling KW - Soil-Structure-Interaction PY - 2023 AN - OPUS4-58365 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Seifert, Lando T1 - Junge GfKORR - Ideen für ein Netzwerk aus Young Professionals N2 - Der Berufsverband GfKORR - Gesellschaft für Korrosionsschutz e.V. will mit der "Jungen GfKORR" ein attraktives Angebot für junge Leute schaffen, sich fachübergreifend zu vernetzen und somit einen Einstieg in die fachliche Arbeit des Verbands zu bieten. Das Netzwerk befindet sich zurzeit im Aufbau. Auf der Jahrestagung 2023 in Berlin wurde die Idee für das Netzwerk erstmals vorgestellt. T2 - Jahrestagung der GfKORR - Gesellschaft für Korrosionsschutz e.V. CY - Berlin, Germany DA - 07.11.2023 KW - Junge GfKORR KW - Netzwerkbildung PY - 2023 AN - OPUS4-58799 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rogge, Andreas T1 - Uncertain climate futures: Insights from Germany N2 - Um den Folgen des Klimawandels für unsere Infrastrukturen zu begegnen, sind grundlegende Änderungen unserer bisherigen Praxis erforderlich. Dies umfasst sowohl den Umgang mit Unsicherheiten in der Prognose kommender Ereignisse als auch den Wechsel von Struktur- auf Systemebene zur Aufrechterhaltung grundlegender Funktionen. T2 - International Workshop on Uncertain Climate Futures, A New Reality for Structural Design and Integrity Management CY - Copenhagen, Denmark DA - 16.06.2025 KW - Global warming KW - Climate change KW - Material reduction KW - Emission PY - 2025 AN - OPUS4-63595 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Unger, Jörg F. T1 - Quantifying the uncertainty of predictive simulations in digital twins through the identification of model bias N2 - This work presents a novel approach to quantifying uncertainty in digital twin simulations by address-ing model bias through embedded parameter distributions. Traditional Bayesian methods often under-estimate uncertainty due to assumptions of model correctness. We propose a hierarchical Bayesian framework combined with Polynomial Chaos Expansion to better capture and propagate uncertainty. The methodology is validated on an analytical example and a real-world case involving thermal defor-mation predictions of the Nibelungen Bridge, demonstrating improved predictive accuracy and relia-bility. T2 - fib Symposium 2025 CY - Antibes, France DA - 16.06.2025 KW - Simulation-based KW - Digital Twins for 3D KW - Concrete printing KW - Bridge Monitoring KW - Bias formulation PY - 2025 AN - OPUS4-63596 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Law, D. W. A1 - Sturm, Patrick A1 - Gluth, Gregor A1 - Gunasekara, C. A1 - Yamchelou, M. T. ED - Banthia, N. ED - Soleimani-Dashtaki, S. ED - Mindess, S. T1 - Characteristics of high calcium fly ash geopolymer mortar N2 - Portland cement is one of the principal sources of anthropomorphic CO2 emissions. It is estimated that cement production contributes up to 10% of greenhouse gas emissions and annual cement production over 4 billion tons. This has led to the development of a range of alkali activated materials (AAM), the most common precursor materials being class F fly ash and blast furnace slag. At present Class C Fly Ash is not widely utilized as an AAM due to the chemical composition and activation requirements. However, initial research on high Calcium German Class C Fly Ash suggests that the material may have potential for application as an AAM. This paper reports the development of ambient cured alkali activated mortar optimised by varying the alkali modulus and w/b ratio. The evolution of the mechanical and microstructural properties is reported over the initial 28 day period. Compressive strength in excess of 10 MPa at 7 days and 15 MPa at 28 days was achieved at ambient temperature. Similar strengths were observed for both 10% and 15% dosage but as dosage increases the optimal Alkali Modulus reduces. T2 - 77th RILEM Annual Week and the 1st Interdisciplinary Symposium on Smart & Sustainable Infrastructures (ISSSI 2023) CY - Vancouver, BC, Canada DA - 04.09.2023 KW - Alkali-activated materials KW - Brown Coal Fly Ash KW - Lignite Coal PY - 2024 SN - 978-3-031-53388-4 SN - 978-3-031-53389-1 DO - https://doi.org/10.1007/978-3-031-53389-1_8 SN - 2211-0844 SN - 2211-0852 VL - 48 SP - 82 EP - 92 PB - Springer CY - Cham AN - OPUS4-59578 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Baeßler, Matthias A1 - Cuéllar, Pablo A1 - Schepers, Winfried T1 - VERBATIM: Project Introduction and Large Scale Experiments N2 - The presentation summarizes the scope of the joint project VERBATIM on buckling of large Monopiles. The presented work from the authors focusses on the experimental field tests of large predented piles during driving and a numerical investigation on the observed buckling behaviour. T2 - Colloquium „Buckling of Offshore Wind Energy Structures“ CY - Berlin, Germany DA - 14.02.2024 KW - Buckling KW - Offshore KW - Wind Energy Structures KW - Monopiles KW - Pile-Tip-Buckling PY - 2024 AN - OPUS4-59535 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ebell, Gino T1 - KI in der Maritimen Korrosionsforschung N2 - Mit dem Klimawandel verändert sich nicht nur das Wetter, also Regenmengen, Temperaturen oder Starkwind- bzw. Sturmzeiten. Mit diesen Veränderungen gehen auch Veränderungen der örtlichen Korro-siviät der Atmosphäre einher. Sind die Datengrundlagen der aktuellen nationalen und internationalen Normen mit Datenerhebungen aus den 1970igern und 80iger Jahren noch repräsentativ? Hierzu werden an realen Offshorestrukturen valide Daten erfasst, die als Grundlage für KI-basierte Modellbildung verwendet werden sollen. T2 - Innovationszirkel der WAB CY - Online meeting DA - 07.02.2024 KW - Korrosion KW - Windenergie KW - Offshore PY - 2024 AN - OPUS4-59488 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ebell, Gino T1 - Performance & Failure Mechanisms of Galvanic Anodes N2 - Galvanic anodes could be used in concrete structures to prevent new anode formation surrounding patch-repaired areas. Therefore so-called galvanic anodes need to be embedded into the fresh concrete with an electroconductive connection to the reinforcement. This anodic area will protect the surrounding reinforcement against forming other anodic areas. T2 - Pre-Consec Workshop 2024 CY - Chennai, India DA - 24.09.2024 KW - Corrosion KW - Galvanic anodes KW - Reinforcement KW - Pitting corrosion PY - 2024 AN - OPUS4-61307 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ebell, Gino A1 - Breit, W. T1 - Investigation of corrosion product layers in chloride containing mortars - "galvanized reinforcement" N2 - In the case of galvanised steel in mortar or concrete, the corrosion behaviour depends on the ion distribution of the pore solution and the pH value. Therefore, a new approach has been developed to determine the corrosion behaviour by single frequency AC measurements and to determine the B-values to calculate the corrosion current density using the Stern-Geary equation. T2 - ICCRRR 2024 CY - Cape Town, South Africa DA - 03.11.2024 KW - Corrosion KW - Galvanized steel PY - 2024 AN - OPUS4-61517 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Zinas, Orestis A1 - Papaioannou, Iason A1 - Schneider, Ronald A1 - Cuéllar, Pablo T1 - Multivariate Gaussian Process for 3D subsurface stratigraphy prediction from CPT and labelled borehole data N2 - Quantifying uncertainties in subsurface properties and stratigraphy can lead to better understanding of the ground conditions and enhance the design and assessment of geotechnical structures. Several studies have utilized Cone Penetration Test (CPT) data and employed Bayesian and Machine Learning methods to quantify the geological uncertainty, based on the Robertson’s soil classification charts and the Soil Behaviour Type Index (Ic). The incorporation of borehole data can reduce the stratigraphic uncertainty. Significant challenges can arise, however, mainly due to the intrinsic differences between field and laboratory-based soil classification systems, which can potentially lead to inconsistent soil classification. To this end, this study proposes a multivariate Gaussian Process model that utilizes site-specific data and: i) jointly models multiple categorical (USCS labels) and continuous (Ic) variables, ii) learns a (shared) spatial correlation structure and the betweenoutputs covariance, and iii) produces two types of dependent classification outputs. The results indicate that the integration of geotechnical and geological information into a unified model can provide more reliable predictions of the subsurface stratification, by allowing simultaneous interpretation of USCS and Ic profiles. Importantly, the model demonstrates the potential to integrate multiple variables of different types, aiming to contribute to the development of a methodology for joint modeling of geotechnical, geological and geophysical data. T2 - 7th International Conference on Geotechnical and Geophysical Site Characterization CY - Barcelona, Spain DA - 18.06.2024 KW - Geotechnical site-characterization KW - Probabilistic KW - Soil classification KW - Gaussian Process PY - 2024 SP - 1733 EP - 1740 AN - OPUS4-60712 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Zinas, Orestis A1 - Papaioannou, Iason A1 - Schneider, Ronald A1 - Cuéllar, Pablo T1 - Spatial modeling of heterogeneous geotechnical site investigation data using multivariate Gaussian Process N2 - This presentation is part of the Engineering Risk Analysis group open seminars. It aims to showcase the results of an ongoing study centered on developing a novel probabilistic methodology for 3D geotechnical site characterization. This methodology integrates data from Cone Penetration Tests (CPTs) and categorical borehole data. The presentation covers the mathematical details of the proposed Multivariate Gaussian Process model and demonstrates its application to a real geotechnical site in New Zealand. T2 - ERA Seminars CY - Munich, Germany DA - 24.07.2024 KW - Geotechnical site-characterization KW - CPT KW - Boreholes KW - Gaussian Process PY - 2024 AN - OPUS4-60716 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Gluth, Gregor T1 - Chemical resistance of hybrid cements against aggressive saline solutions N2 - The safe storage of radioactive material in nuclear waste repositories is a major task of our societies. The sealing function of such repositories is depending on the ability of the applied construction materials to form and maintain a geotechnical barrier with the surrounding rock. Corrosion of the construction material can lead to leakage of radioactive compounds and must therefore be avoided or minimized. Since concretes based on conventional Portland cement have not been found suitable in this context, alternative binders must be evaluated. One such class of binders are hybrid cements, which are blends of low fractions of Portland cement or Portland clinker and high fractions of supplementary cementitious materials, such as blast furnace slag and fly ash, activated by an alkali salt. Besides a low heat of hydration and a sufficient early compressive strength [1], chemical similarities with ancient Roman concrete suggest an excellent durability in saline environments [2], which makes these cements potentially suitable for applications in nuclear waste repositories in evaporite rock, such as the Morsleben repository in Germany. In the present study, two previously designed and characterized [3] hybrid cements, an alkali-activated slag/fly ash blend, and an OPC paste were studied regarding their resistance against corrosion in an aggressive saline solution. The saline solution was designed by the Gesellschaft für Anlagen- und Reaktorsicherheit (GRS) [Association for Facility and Reactor Safety] as a reference representing a solution forming as the result of contact of surface water with evaporite rock. The cement pastes were exposed to the saline solution up to 70 days and characterized by X-ray diffraction, thermogravimetric analysis and spatially resolved X-ray fluorescence spectroscopy. In addition, thermodynamic modelling was performed to simulate the alterations of the phase assemblage with increasing exposure to the saline solution and, thus, provide indications on the long-term durability of the cement pastes. The experimental results revealed a correlation between the Portland clinker content of the cements and the resistance of the cement pastes against attack by the saline solution. This outcome was related to the formation of portlandite when sufficient clinker was available, which maintained the pore solution pH at ~12.5, and thus prevented the dissolution of cementitious phases. Once portlandite was consumed, C-N-A-S-H and ettringite dissolved and released calcium, aluminium, and hydroxide ions in the solution, maintaining the pH at ~10. In this pH range, the formation Cl-AFm phases was observed. At lower pH values, i.e., extended exposure durations, gypsum was the major corrosion product. The pH-dependent dissolution and formation of phases lead to pronounced zonation in the exposed cement pastes. Thermodynamic modelling indicated that the dissolved silicon from C-N-A-S-H reacts with magnesium ions in the saline solution to form M-S-H, and that long-term exposure eventually leads to a material rich in amorphous silica and brucite. T2 - Joint 6th International Workshop on Mechanisms and Modelling of Waste / Cement Interactions & EURAD - WP CORI Workshop CY - Prague, Czech Republic DA - 20.11.2023 KW - Hybrid cement KW - Corrosion KW - Salt solution KW - Magnesium chloride KW - Evaporite rock PY - 2023 AN - OPUS4-58885 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sittner, Jonathan T1 - Calcined clays: Innovative production of cost-effective and sustainable supplementary cementitious materials N2 - Calcined clays are promising sustainable alternative materials for cement production. By calcining natural clay minerals (usually 600–900 °C), they become reactive and can be used as a partial replacement for Portland clinker in cement production. This results in a lower carbon footprint and reduced energy consumption in the production process. Replacing cement clinker with so-called supplementary cementitious materials (SCM) such as fly ash and blast furnace slag has been done for several decades. Calcined clays have also been used, mostly in the form of metakaolin, which significantly improves the strength and durability of mortar and concrete. However, its limited availability and high cost restrict its practical application to a few specialist applications. In comparison, 2:1 clay minerals such as illite or smectites are more widely available and economically attractive due to their lower costs. Recent research has explored the use of calcined 2:1 clay minerals as SCM, but their properties and efficient production are still not fully understood. In the present work, different clays from Germany are characterized and tested as potential calcined clay. Besides conventional calcination using a rotary kiln, fluidized bed calcination is used to improve the reactivity of the calcined clays while being less time-consuming and therefore more energy efficient. T2 - GeoSaxonia 2024 CY - Dresden, Germany DA - 23.09.2024 KW - Calcined clay KW - Supplementary cementitious material (SCM) PY - 2024 AN - OPUS4-61973 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ebell, Gino T1 - Korrosion von Zink unter variierenden Bedingungen N2 - Die Korrosionsbeständigkeit von zink in variierenden Elektrolyten hängt von der Deckschichtstabilität und Resistenz gegenüber dem Elektrolyten ab. Das amphotere Verhalten von Zinkhydroxid führt dazu das Zink in sauren und alkalischen Elektrolyten deutlich höhere Korrosionsraten erfährt als in pH-neutralen leicht alkalischen Elektrolyten. In diesem Vortrag werden verschiedene Anwendungsfälle dargestellt. T2 - Gemeinschaftssitzung des AK atmosphärische Korrosion und Elektrotechnik CY - Online meeting DA - 05.12.2024 KW - Corrosion KW - Korrosion KW - Zink PY - 2024 AN - OPUS4-62010 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Pötzsch, Sina A1 - Weltschev, Margit A1 - Bäßler, Ralph T1 - Compatibility of polymers exposed to heating oil blends with 10 % and 20 % biodiesel (FAME) N2 - Biodiesel (FAME) from rapeseed is an environmentally friendly alternative to common fossil fuels. It is also suitable to serve as blending component to fuels like heating oil. If the fuel composition is changed, materials compatibility must be guaranteed. Adding polar biodiesel to nonpolar heating oil, changes the blend’s solvency and might cause swelling, extraction and solvation of polymers. The objective of this research was to investigate the compatibility of polymeric materials, which are commonly used for components in middle distillate facilities, along with blends of heating oil and 20 % biodiesel (B20). For this propose, ACM, HNBR, FKM, PE, PA 6, POM, PUR and PVC were exposed to heating oil and B20 for 42 and 84 days at 40 °C. In addition, the polymers HNBR, FKM, PA, POM and PVC were also exposed at 70 °C. Furthermore, the resistance of polymers in eight-year aged B10 at 40 °C was evaluated. Ageing of biodiesel increases acidity which might propagate polymer corrosion. The materials were evaluated as resistant, if the loss in tensile properties (tensile strength and elongation at break) and Shore hardness remained under 15 % compared to the initial unexposed material values. For investigations under compressed conditions, the compression set was determined for specimens of ACM, FKM and HNBR after exposure in heating oil B0 and B20 for 3,7,14, 28, 56 and 90 days at 40 °C according to ISO 815-1. It was found that the resistance in B20 at 40 °C was given for all tested polymers except PUR. In the 8 years aged B10, PUR and POM were not compatible and ACM just conditionally compatible. At 70 °C, FKM and PVC were resistant in B20, whereas HNBR and PA 6 were not compatible. Swelling occurred for the elastomers ACM, HNBR and PUR. T2 - AMPP Annual International Corrosion Conference 2021 CY - Online Meeting DA - 19.04.2021 KW - Biodiesel KW - FAME KW - RME KW - Polymer in fuels PY - 2021 SP - 16222-01 EP - 16222-12 CY - Houston AN - OPUS4-52499 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bäßler, Ralph T1 - Compatibility of polymers exposed to heating oil blends with 10 % and 20 % biodiesel (FAME) N2 - Biodiesel (FAME) from rapeseed is an environmentally friendly alternative to common fossil fuels. It is also suitable to serve as blending component to fuels like heating oil. If the fuel composition is changed, materials compatibility must be guaranteed. Adding polar biodiesel to nonpolar heating oil, changes the blend’s solvency and might cause swelling, extraction and solvation of polymers. The objective of this research was to investigate the compatibility of polymeric materials, which are commonly used for components in middle distillate facilities, along with blends of heating oil and 20 % biodiesel (B20). For this propose, ACM, HNBR, FKM, PE, PA 6, POM, PUR and PVC were exposed to heating oil and B20 for 42 and 84 days at 40 °C. In addition, the polymers HNBR, FKM, PA, POM and PVC were also exposed at 70 °C. Furthermore, the resistance of polymers in eight-year aged B10 at 40 °C was evaluated. Ageing of biodiesel increases acidity which might propagate polymer corrosion. The materials were evaluated as resistant, if the loss in tensile properties (tensile strength and elongation at break) and Shore hardness remained under 15 % compared to the initial unexposed material values. For investigations under compressed conditions, the compression set was determined for specimens of ACM, FKM and HNBR after exposure in heating oil B0 and B20 for 3,7,14, 28, 56 and 90 days at 40 °C according to ISO 815-1. It was found that the resistance in B20 at 40 °C was given for all tested polymers except PUR. In the 8 years aged B10, PUR and POM were not compatible and ACM just conditionally compatible. At 70 °C, FKM and PVC were resistant in B20, whereas HNBR and PA 6 were not compatible. Swelling occurred for the elastomers ACM, HNBR and PUR. T2 - AMPP Annual International Corrosion Conference CY - Online Meeting DA - 19.04.2021 KW - Biodiesel KW - FAME KW - RME KW - Polymer in fuels KW - Corrosion PY - 2021 AN - OPUS4-52498 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Grengg, C. A1 - Gluth, Gregor A1 - Mittermayr, F. A1 - Ukrainczyk, N. A1 - Bertmer, M. A1 - de Oliveira Guilherme Buzanich, Ana A1 - Radtke, Martin A1 - Leis, A. A1 - Dietzel, M. T1 - Deterioration mechanism of alkali-activated materials in sulfuric acid and the influence of Cu: A micro-to-nano structural, elemental and stable isotopic multi-proxy study N2 - In this study, a multi-proxy approach combining 29Si, 27Al and 1H MAS-NMR, FEG-EPMA, XANES at the Cu K-edge and XRD analytics with hydrochemical tools such as ICP-OES analyses, oxygen-isotope signatures, and thermodynamic modelling was applied to K-silicate-activated metakaolin specimens - with and without CuSO4·5H2O addition - exposed to sulfuric acid at pH = 2 for 35 days. The results revealed a multistage deterioration mechanism governed by (i) acid diffusion, (ii) leaching of K-A-S-H, (iii) microstructural damage related to precipitation of expansive (K,Ca,Al)-sulfate-hydrate phases (iv) complete dissolution of the K-A-S-H framework, (v) and formation of silica gel in the outermost corroded regions. Copper ions were mainly located in layered spertiniite-chrysocolla-like phases in the as-cured materials. The results demonstrate an overall negative effect of Cu addition on chemical material durability, implying that the reported higher durability of Cu-doped AAM in biocorrosion environments can be best explained by bacteriostatic effects. KW - Alkali-activated materials KW - Acid resistance KW - Microbially induced corrosion KW - MIC PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-520567 DO - https://doi.org/10.1016/j.cemconres.2021.106373 SN - 0008-8846 VL - 142 SP - 1 EP - 15 PB - Elsevier CY - Oxford AN - OPUS4-52056 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bäßler, Ralph T1 - Materials interactions in geothermal plants – not just an aspect of durability N2 - High alloyed corrosion resistant alloys are suitable for high saline geothermal fluids and do not cause copper or lead deposition. They shall be chosen for future design of the piping system, either in massive or in cladded form, if crevices formation with non-metallic materials can be prevented! Otherwise Ni-based alloys or Ti shall be selected. T2 - IFPEN Webinar "Corrosion in geothermal energy production" CY - Online meeting DA - 26.06.2025 KW - Corrosion KW - Geothermal KW - Electrochemistry PY - 2025 AN - OPUS4-63528 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kühnel, Alena T1 - 3D-Ansprache von texturierten Straßenoberflächen N2 - Im Vortrag wurden die Möglichkeiten der 3D-messtechnischen Erfassung und Charakterisierung von Betonfahrbahnoberflächen anhand geeigneter Kenngrößen aufgezeigt. Zudem wurden Ergebnisse aus dem Monitoring zweier Praxisstrecken im deutschen Bundesautobahnnetz miteinander verglichen und gegenübergestellt. T2 - Forschungskolloquium Betonstraßenbau CY - Stuttgart, Germany DA - 06.02.2025 KW - Betonfahrbahndecken KW - 3D Erfassung KW - Oberflächentexturen KW - Texturgrinding PY - 2025 AN - OPUS4-63423 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Cuéllar, Pablo T1 - Geotechnical challenges in the field of Offshore Wind Energy. Micromechanical perspectives beyond the FEM N2 - This talk provides a brief overview on some geomechanical phenomena and problematic issues in the field of offshore wind-energy geotechnics, with reference to their associated challenges for a numerical analysis/simulation. These may include large deformations, fluid coupling and grain-scale phenomena, all of which are generally difficult to be addressed with conventional FE techniques. These challenges are illustrated here with a practical example for the retrofit of axially loaded piles using compaction grouting techniques. In this case, the mechanical effects of the retrofit may be analysed with standard FE techniques, but require the adoption of strong assumptions, while the injection process itself can only be analysed with special techniques such as the MPM. Finally, an LBM-DEM framework for the micromechanical analysis of such problems is introduced and a practical application for the estimation of the soil resistance to driving (SRD) in layered profiles is discussed. T2 - Online Symposium on Meshfree models for Engineers: Where are they really worthwhile? CY - Online meeting DA - 01.12.2022 KW - Offshore wind energy KW - Offshore geotechnics KW - Micromechanical simulation KW - LBM-DEM KW - Pile retrofit system PY - 2022 AN - OPUS4-56450 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ebell, Gino T1 - Potentialfeldmessung in Theorie und Praxis N2 - Durch das alkalische Porenwassermilieu ist Stahl im Beton vor Korrosion geschützt. Unter ungünstigen Umgebungsbedingungen (Karbonatisierung, Chlorideintrag) kann die passive Deckschicht auf der Stahloberfläche zerstört werden. Im weiteren Verlauf können sich korrosionsbedingte Folgeschäden, wie Risse und Abplatzungen am Bauwerk ergeben. Um notwendige Sanierungsmaßnahmen sind frühzeitige und weitgehend zerstörungsfrei ermittelte Informationen über das aktuelle Korrosionsverhalten der Stahlbewehrung von großer Bedeutung. Die Potentialfeldmessung ist ein etabliertes und weit verbreitetes Verfahren zur Beurteilung des Korrosionszustandes der Bewehrung in Stahlbetonbauwerken. Mit Hilfe dieses Verfahrens können Bereiche aktiv korrodierender Bewehrung zerstörungsfrei lokalisiert werden. In der Regel kommt diese Messmethode bei der Detektion chloridinduzierter Korrosion zum Einsatz T2 - TU-Vorlesung CY - Berlin, Germany DA - 28.06.2023 KW - Korrosion KW - Potentialfeldmessung PY - 2023 AN - OPUS4-57883 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Farhat, Abbas A1 - Philippe, Pierre A1 - Luu, Li-Hua A1 - Doghmane, Alexis A1 - Cuéllar, Pablo T1 - Hydraulic failure of granular materials with artificial cementation N2 - This paper presents an experimental study on the hydraulic failure of a submerged layer of cemented soil stressed by a localized upward water flow. Different mixtures of glass beads bonded with solid paraffin bridges were used as artificial material for the cemented granular soil. Variations in the cementation strength of the material were carefully introduced with different particle sizes and binder contents. The hydraulic fracture tests were then carried out with an upward flow injected at a controlled rate through a small section at the bottom of the samples. From a phenomenological perspective, the results reveal the existence of at least three modes of failure for a cemented soil layer: (1) overall block uplift, (2) block rupture by median crack at the inflow zone, and (3) progressive excavation of a fluidized path along the walls. The critical flow rate and pressure drop conditions at failure have been carefully quantified for the different mixtures and layer thicknesses, leading to a fair estimation of the hydraulic resistance of the samples, which here is found to be virtually independent of the grain size. However, the test results also showed inconsistent failure modes precluding so far the derivation of a simple phase diagram. Nevertheless, it was possible to rationalize all the measured data by employing appropriate modifications of the classical dimensionless numbers that describe the fluidization of purely frictional materials, whereby the cementation strength of the soil is quantified at the microscale through the yield tensile force of the intergranular bonds. Irrespective of its subsequent development, during which boundary conditions obviously play a major role, the initiation of the instability appears to take place very locally at the inlet when the drag force induced by the flow overcomes the cementation strength of the paraffin bonds. The results of this study thus appear to endorse the extension of the dimensional relationships of particulate systems in interaction with fluid flows to the case of cemented granular materials, in a similar vein as in recent previous studies. KW - Fluidized beds KW - Granular materials KW - Fluid Dynamics KW - Cemented soil PY - 2024 DO - https://doi.org/10.1103/PhysRevFluids.9.064305 SN - 2469-990X VL - 9 IS - 6 SP - 1 EP - 13 PB - American Physical Society AN - OPUS4-60803 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Gluth, Gregor A1 - Grengg, C. A1 - Ukrainczyk, N. A1 - Mittermayr, F. A1 - Dietzel, M. T1 - Acid resistance of alkali-activated materials: Recent advances and research needs N2 - Cementitious materials are frequently applied in environments in which they are exposed to acid attack, e.g., in sewer systems, biogas plants, and agricultural/food-related industries. Alkali-activated materials (AAMs) have repeatedly been shown to exhibit a remarkably high resistance against attack by organic and inorganic acids and, thus, are promising candidates for the construction and the repair of acid-exposed structures. However, the reaction mechanisms and processes affecting the acid resistance of AAMs have just recently begun to be understood in more detail. The present contribution synthesises these advances and outlines potentially fruitful avenues of research. The interaction between AAMs and acids proceeds in a multistep process wherein different aspects of deterioration extend to different depths, complicating the overall determination of acid resistance. Partly due to this indistinct definition of the ‘depth of corrosion’, the effects of the composition of AAMs on their acid resistance cannot be unambiguously identified to date. Important parallels exist between the deterioration of low-Ca AAMs and the weathering/corrosion of minerals and glasses (dissolution-reprecipitation mechanism). Additional research requirements relate to the deterioration mechanism of high-Ca AAMs; how the character of the corroded layer influences the rate of deterioration; the effects of shrinkage and the bond between AAMs and substrates. KW - Alkali-activated materials KW - Acid attack KW - Acid resistance KW - Concrete repair KW - MIC PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-557376 DO - https://doi.org/10.21809/rilemtechlett.2022.157 SN - 2518-0231 VL - 7 SP - 58 EP - 67 PB - RILEM Publications SARL CY - Paris AN - OPUS4-55737 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Rudić, O. A1 - Mittermayr, F. A1 - Gluth, Gregor A1 - Simon, Sebastian A1 - Ukrainczyk, N. A1 - Seyrek, Y. A1 - Freytag, B. A1 - Juhart, J. A1 - Grengg, C. T1 - On the benefits of vegetable oil addition for the pore structure and acid resistance of alkali-activated systems N2 - The impact of high additions of vegetable oil (12 vol%) on the mechanical and microstructural properties of metakaolin-slag-based alkali-activated materials (AAMs) was studied. The addition of oil resulted in a slight decrease in initial polymerization kinetics but did not affect the final degree of reaction. AAM-oil-composite-mortars exhibited approximately ∼30% lower compressive strength primarily due to the entrainment of air voids. Newly formed soap phases significantly reduced the volume of small capillary and gel pores (pore radii <15 nm), leading to a decrease in specific inner surface area by a factor of up to 15. The porosity modification induced by the oil addition greatly enhanced the resistance of AAMs against sulfuric acid attack, shifting the dominant processes from diffusion and cracks to framework-dissolution controlled by the inherent phase stabilities. Following the immersion in sulfuric acid (pHstat = 2) for 8 weeks, the depth of corroded layer decreased by 70% and no cracks due to expansive phases were observed. These promising findings suggest that the incorporation of vegetable oil in AAMs has the potential to address durability concerns associated with diffusion-based corrosion processes, thereby expanding the range of future applications. KW - Alkali-activated materials KW - Acid resistance KW - Pore structure PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-581719 DO - https://doi.org/10.1016/j.ceramint.2023.08.036 VL - 49 IS - 20 SP - 33275 EP - 33290 PB - Elsevier Ltd. AN - OPUS4-58171 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Mundra, S. A1 - Samson, G. A1 - Masi, G. A1 - Achenbach, R. A1 - Bastidas, D. M. A1 - Bernal, S. A. A1 - Bignozzi, M. C. A1 - Criado, M. A1 - Cyr, M. A1 - Gartner, N. A1 - von Greve-Dierfeld, S. A1 - Legat, A. A1 - Nikoonasab, Ali A1 - Provis, J. L. A1 - Raupach, M. A1 - Gluth, Gregor T1 - Application of electrochemical methods for studying steel corrosion in alkali-activated materials N2 - Alkali-activated materials (AAMs) are binders that can complement and partially substitute the current use of conventional cement. However, the present knowledge about how AAMs protect steel reinforcement in concrete elements is incomplete, and uncertainties exist regarding the application of electrochemical methods to investigate this issue. The present review by EFC WP11-Task Force ‘Corrosion of steel in alkali-activated materials’ demonstrates that important differences exist between AAMs and Portland cement, and between different classes of AAMs, which are mainly caused by differing pore solution compositions, and which affect the outcomes of electrochemical measurements. The high sulfide concentrations in blast furnace slag-based AAMs lead to distinct anodic polarisation curves, unusually low open circuit potentials, and low polarisation resistances, which might be incorrectly interpreted as indicating active corrosion of steel reinforcement. No systematic study of the influence of the steel–concrete interface on the susceptibility of steel to corrosion in AAMs is available. Less common electrochemical methods present an opportunity for future progress in the field. KW - Alkali-activated materials KW - Reinforcement corrosion KW - Steel corrrosion KW - Electrochemical methods KW - Concrete PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-572241 DO - https://doi.org/10.1002/maco.202313743 SN - 1521-4176 VL - 74 IS - 7 SP - 988 EP - 1008 PB - Wiley-VCH CY - Weinheim AN - OPUS4-57224 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Henning, Ricky A1 - Sturm, Patrick A1 - Geddes, D.A. A1 - Keßler, S. A1 - Walkley, B. A1 - Gluth, Gregor T1 - The influence of curing temperature on the strength and phase assemblage of hybrid cements based on GGBFS/FA blends N2 - Hybrid cements are composites made of Portland cement or Portland clinker and one or more supplementary cementitious materials like slag, fly ash or metakaolin, activated with an alkali salt. To date, their hydration mechanism and the phase formation at various temperatures is insufficiently understood, partly due to the large variability of the raw materials used. In the present study, three hybrid cements based on ground granulated blast furnace slag, fly ash, Portland clinker and sodium sulfate, and an alkali-activated slag/fly ash blend were cured at 10 and 21.5°C, and subsequently analyzed by XRD, 27Al MAS NMR, and TGA. The compressive strength of the hybrid cements was higher by up to 27% after 91-day curing at 10°C, compared to curing at 21.5°C. The experimental results as well as thermodynamic modeling indicate that the differences in compressive strength were related to a different phase assemblage, mainly differing amounts of strätlingite and C-N-A-S-H, and the associated differences of the volume of hydration products. While the strätlingite was amorphous to X-rays, it could be identified by 27Al MAS NMR spectroscopy, TGA and thermodynamic modeling. The microstructural properties of the hybrid cements and the alkali-activated slag/fly ash blend as well as the compatibility between thermodynamic modeling results and experimental data as a function of curing temperature and time are discussed. KW - Hybrid cements KW - Strätlingite KW - Thermodynamic modelling KW - Hydration PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-557767 DO - https://doi.org/10.3389/fmats.2022.982568 SN - 2296-8016 VL - 9 SP - 1 EP - 16 PB - Frontiers AN - OPUS4-55776 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Gluth, Gregor A1 - Ke, X. A1 - Vollpracht, A. A1 - Weiler, L. A1 - Bernal, S. A. A1 - Cyr, M. A1 - Dombrowski-Daube, K. A1 - Geddes, D. A. A1 - Grengg, C. A1 - Le Galliard, C. A1 - Nedeljkovic, M. A1 - Provis, J. L. A1 - Valentini, L. A1 - Walkley, B. T1 - Carbonation rate of alkali-activated concretes and high-volume SCM concretes: a literature data analysis by RILEM TC 281-CCC N2 - The current understanding of the carbonation and the prediction of the carbonation rate of alkali-activated concretes is complicated inter alia by the wide range of binder chemistries used and testing conditions adopted. To overcome some of the limitations of individual studies and to identify general correlations between mix design parameters and carbonation resistance, the RILEM TC 281-CCC ‘Carbonation of Concrete with Supplementary Cementitious Materials’ Working Group 6 compiled and analysed carbonation data for alkali-activated concretes and mortars from the literature. For comparison purposes, data for blended Portland cement-based concretes with a high percentage of SCMs (≥ 66% of the binder) were also included in the database. The analysis indicates that water/CaO ratio and water/binder ratio exert an influence on the carbonation resistance of alkali-activated concretes; however, these parameters are not good indicators of the carbonation resistance when considered individually. A better indicator of the carbonation resistance of alkali-activated concretes under conditions approximating natural carbonation appears to be their water/(CaO + MgOeq + Na2Oeq + K2Oeq) ratio, where the subscript ‘eq’ indicates an equivalent amount based on molar masses. Nevertheless, this ratio can serve as approximate indicator at best, as other parameters also affect the carbonation resistance of alkali-activated concretes. In addition, the analysis of the database points to peculiarities of accelerated tests using elevated CO2 concentrations for low-Ca alkali-activated concretes, indicating that even at the relatively modest concentration of 1% CO2, accelerated testing may lead to inaccurate predictions of the carbonation resistance under natural exposure conditions. KW - Alkali-activated materials KW - Durability KW - Carbonation KW - Accelerated testing PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-560037 DO - https://doi.org/10.1617/s11527-022-02041-4 VL - 55 IS - 8 SP - 1 EP - 15 PB - Springer Nature AN - OPUS4-56003 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Ginés-Palomares, J.-C. A1 - Fateri, M. A1 - Schubert, T. A1 - de Peindray d’Ambelle, L. A1 - Simon, Sebastian A1 - Gluth, Gregor A1 - Günster, Jens A1 - Zocca, Andrea T1 - Material aspects of sintering of EAC-1A lunar regolith simulant N2 - Future lunar exploration will be based on in-situ resource utilization (ISRU) techniques. The most abundant raw material on the Moon is lunar regolith, which, however, is very scarce on Earth, making the study of simulants a necessity. The objective of this study is to characterize and investigate the sintering behavior of EAC-1A lunar regolith simulant. The characterization of the simulant included the determination of the phase assemblage, characteristic temperatures determination and water content analysis. The results are discussed in the context of sintering experiments of EAC-1A simulant, which showed that the material can be sintered to a relative density close to 90%, but only within a very narrow range of temperatures (20–30 °C). Sintering experiments were performed for sieved and unsieved, as well as for dried and non-dried specimens of EAC-1A. In addition, an analysis of the densification and mechanical properties of the sintered specimens was done. The sintering experiments at different temperatures showed that the finest fraction of sieved simulant can reach a higher maximum sintering temperature, and consequently a higher densification and biaxial strength. The non-dried powder exhibited higher densification and biaxial strength after sintering compared to the dried specimen. This difference was explained with a higher green density of the non-dried powder during pressing, rather than due to an actual influence on the sintering mechanism. Nevertheless, drying the powder prior to sintering is important to avoid the overestimation of the strength of specimens to be fabricated on the Moon. KW - Lunar regolith KW - Ceramics KW - Microstructure KW - Sintering KW - Softening temperature PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-592668 DO - https://doi.org/10.1038/s41598-023-50391-y SN - 2045-2322 VL - 13 SP - 1 EP - 14 PB - Springer Nature AN - OPUS4-59266 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Simon, Sebastian A1 - Bertmer, M. A1 - Gluth, Gregor T1 - Sol–gel synthesis and characterization of lithium aluminate (L–A–H) and lithium aluminosilicate (L–A–S–H) gels N2 - Hydrous lithium aluminosilicate (L–A–S–H) and lithium aluminate (L–A–H) gels are candidate precursors for glass-ceramics and ceramics with potential advantages over conventional processing routes. However, their structure before calcination remained largely unknown, despite the importance of precursor structure on the properties of the resulting materials. In the present study, it is demonstrated that L–A–S–H and L–A–H gels with Li/Al ≤ 1 can be produced via an organic steric entrapment route, while higher Li/Al ratios lead to crystallization of gibbsite or nordstrandite. The composition and the structure of the gels was studied by thermogravimetric analysis, X-ray diffraction, 27Al and 29Si magic-angle spinning nuclear magnetic resonance, and Raman spectroscopy. Aluminium was found to be almost exclusively in six-fold coordination in both the L–A–H and the L–A–S–H gels. Silicon in the L–A–S–H gels was mainly in Q4 sites and to a lesser extent in Q3 sites (four-fold coordination with no Si–O–Al bonds). The results thus indicate that silica-rich and aluminium-rich domains formed in these gels. KW - Lithium aluminosilicates KW - Raman spectroscopy KW - Sol-gel PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-558756 DO - https://doi.org/10.1111/ijac.14187 SN - 1546-542X VL - 19 IS - 6 SP - 3179 EP - 3190 PB - Wiley AN - OPUS4-55875 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Licht, M. A1 - Nikoonasab, Ali A1 - Gluth, Gregor A1 - Raupach, M. ED - Claßen, M. ED - Hegger, J. ED - Matschei, T. ED - Raupach, M. T1 - Alkali-aktivierte Hüttensandbetone – CO2-reduzierte Bindemittel mit hohem Korrosionsschutzpotential N2 - Durch den Ersatz von Portlandzement können alkali-aktivierte Bindemittel einen bedeutenden Beitrag zur Verringerung der durch die Zementklinkerherstellung verursachten CO2-Emissionen leisten. Für die Verwendung von alkali-aktivierten Bindemitteln in Stahlbetonkonstruktionen, die Chloriden oder Carbonatisierung ausgesetzt sind, ist die Fähigkeit des Stahls, den passiven Zustand zu erreichen und aufrechtzuerhalten, von großer Bedeutung. Die Prozesse der Deckschichtbildung von Stahl in alkali-aktivierten Materialien unterscheiden sich jedoch zum Teil grundlegend von denen in Portlandzementen. Alkali-aktivierte Hüttensandbetone weisen gute technische Eigenschaften auf, bisher fehlen jedoch grundlegende Kenntnisse bzgl. ihrer schützenden Wirkung bei korrosiven Angriffen. Dies ist vor allem auf ihre sulfidhaltige Porenlösung zurückzuführen, welche die elektrochemischen Eigenschaften der Stahloberfläche beeinflusst und die Verwendung herkömmlicher Bewertungsmaßstäbe erschwert. Es werden erste Ergebnisse eines DFG-Forschungsprojektes vorgestellt, in dem das Passivierungsverhalten von Stahl in alkali-aktivierten Hüttensandmörteln unterschiedlicher Zusammensetzungen sowie in Mörteln auf Basis hüttensandhaltiger Normzemente untersucht wird. Über einen Zeitraum von mindestens 28 Tagen werden an Zylinderprüfkörpern im 3-Elektroden-Aufbau das Ruhepotential sowie die Polarisationswiderstände der Stahlelektroden ermittelt. T2 - 10. DAfStb-Jahrestagung mit 62. Forschungskolloquium CY - Aachen, Germany DA - 26.09.2023 KW - Bewehrung KW - Stahlkorrosion KW - Hüttensandmehl KW - Sulfid PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-593775 DO - https://doi.org/10.18154/RWTH-2023-06676 SP - 233 EP - 238 PB - RWTH Aachen CY - Aachen AN - OPUS4-59377 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - THES A1 - Priebe, Nsesheye Susan T1 - Influence of calcination conditions and varying compositions on the reactivity and performance of brick clays as supplementary cementitious materials T1 - Der Einfluss von Kalzinierungsbedingungen und verschiedenen Zusammensetzungen auf die Reaktivität und Eigenschaften von Ziegeltonen verwendet als Zusatzstoffe in Beton N2 - Calcined clays as supplementary cementitious materials (SCMs) have been identified and credited to be a viable solution in mitigating the CO2 emissions related to cement production and consumption. Calcined clays range from a variety of different clay types based on an assortment of varying minerals and compositions. While extensive data is available on kaolinitic clays (based on the 1:1 clay type), other clays such as brick clays (based on the 2:1 clay type) are currently understudied, although such clays are largely more available than the kaolinitic clays. The aim of this thesis is to draw attention to the varying compositions present in two selected brick clays in Germany and elaborate on how such compositions affect their suitability to be used as SCMs in blended cement systems. The novelty of this thesis explains the relationship between the reactivity of the bricks to their varying compositions and their suitability for their employment as SCMs. This was based on their chemical and physical transformations in the calcination temperature range 650–900 or 950 °C, and the performance of the calcined brick clays in blended cement systems measured by their heat evolution, strength development and durability-related properties. The results of their performance were compared to two kaolinitic clays with varying compositions. While the kaolinitic clays generally exhibited the best performance as SCMs, the brick clay with a lower Fe2O3 content showed promising results similar to the kaolinitic clays when an optimum calcination temperature is applied and when substituted at a moderate cement substitution rate. Thus, this finding promoted further efforts made to improve the reactivity of the brick clay by producing a mixed clay composed of 50 % brick clay (with lower Fe2O3 content) and 50 % kaolinitic clay. The mixed clay was compared to the two individual brick clays and one kaolinitic clay, whereby optimum calcination conditions were performed in large-scale simulating an industrial-scale production of SCMs. All calcined clays exhibited pozzolanic reactivity, with the performance of the brick clays inferior to the kaolinitic clay, however, the mixed clay performed very similar to the kaolinitic clay. At a similar degree of hydration compared to plain Portland cement, the good performance of the mixed clays was especially evident in the strength development and improved chloride penetration resistance, which was caused by a refinement in the pore structure in the cementitious systems. Moreover, it was deduced that not only the high surface area, but also, the solubility of Si and Al ions in the resulting calcinate of the mixed clays plays a significant role when calcined at ~600–700 °C, which points to viable options for optimal employment of brick clays in cementitious systems. N2 - Die bei der Zementproduktion freigesetzte CO2-Menge und die daraus resultierenden Folgen für das Klima machen die Entwicklung von Zementersatzstoffen mit geringerem CO2-Fußabdruck erforderlich. Als besonders vielversprechend haben sich dabei die kalzinierten Tone erwiesen. Bei diesen handelt es sich um komplexe Systeme, bestehend aus einer Vielzahl verschiedener Tonminerale in variierender Konzentration und Zusammensetzung. Während für kaolinitische Tone (basierend auf 1:1 Tonmineralarten) bereits umfangreiche Daten gesammelt werden konnten, ist der Kenntnisstand zu anderen Tonarten z.B. Ziegeltonen (basierend auf 2:1 Tonmineralarten) derzeit noch unzureichend. Besonders vor dem Hintergrund der erheblich größeren Verfügbarkeit dieser Tonarten stellt dies einen erheblichen Nachteil dar. Ziel dieser Arbeit ist es, anhand zweier Ziegeltone aus Deutschland, aufzuzeigen welche Auswirkung die unterschiedliche Zusammensetzung der Tone sowohl auf die Reaktivität als auch auf den Einsatz als Zementersatzstoffen in Mischzementsystemen hat. Entsprechende Änderungen in der Zusammensetzung der kalzinierten Tone wurden durch die Variation der Kalzinierungstemperatur im Temperaturbereich zwischen 650 °C und 900 °C bzw. 950 °C und den folglich unterschiedlich ablaufenden chemischen und physikalischen Umwandlungsprozessen der Tonminerale erreicht. Die Leistungsfähigkeit dieser Systeme wurde anhand der Wärme- und Festigkeitsentwicklung sowie den Dauerhaftigkeitseigenschaften bewertet. Als Referenzsysteme dienten zwei 1:1 Tone mit unterschiedlicher Zusammensetzung. Die bei den 1:1 Tonen erzielten Reaktivitäten waren im Vergleich zu den Ziegeltonen zwar höher, aber bei entsprechender Kalzinierungstemperatur und moderater Zementersatzrate konnten auch bei den Ziegeltonen vielversprechende Ergebnisse erzielt werden. Basierend auf diesen Ergebnissen wurden in einem weiteren Schritt Mischtone, bestehend aus kaolinitischem Ton und Ziegelton mit geringerem Fe2O3 Gehalt (50:50), untersucht. Zur Bewertung wurden die zuvor untersuchten Ziegeltone und ein 1:1 Ton herangezogen. Bei allen kalzinierten Tonen konnte die pozzolanische Reaktion nachgewiesen werden, wobei der Ziegelton die geringsten und die 1:1 Tone die höchsten Werte lieferte. Das Mischtonsysteme sind leistungstechnisch bei den 1:1 Tonen einzuordnen. Die strukturverfeinernde Wirkung des Mischtons beim Einsatz als Zementersatz in Portlandzementsystemen führte sowohl bei der Festigkeitsentwicklung als auch beim Chlorideindringwiderstand zu einer Leistungssteigerung. Zudem konnte gezeigt werden, dass nicht nur die große spezifische Oberfläche, sondern auch die hohe Löslichkeit der Si- und Al-Ionen in den Kalzinaten der bei ~600-700 °C kalzinierten Mischtone einen großen Einfluss hat und den Einsatz der Ziegeltone in zementären Systemen begünstigt. Die Möglichkeit zur Herstellung von Zementersatzstoffen im industriellen Maßstab konnte durch Versuche im Großmaßstab ebenfalls nachgewiesen werden. KW - Blended cement KW - Brick clay KW - Calcined clay KW - Hydration KW - Illite KW - Kalzinierte Tone KW - Ziegelton PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:co1-opus4-58816 DO - https://doi.org/10.26127/BTUOpen-5881 SP - i EP - 153 PB - Brandenburgische Technische Universität Cottbus-Senftenberg CY - Cottbus AN - OPUS4-55048 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Ebell, Gino A1 - Burkert, Andreas A1 - Günther, Tobias A1 - Wilsch, Gerd T1 - Untersuchungen zum korrosionsauslösenden Chloridgehalt an nicht rostendem ferritischem Betonstahl in Mörtel N2 - Der maßgebliche Korrosionsschutz von nicht rostendem Stahl in Beton basiert, anders als bei unlegiertem Betonstahl, auf der Ausbildung einer Chromoxidschicht. Die Chromoxidschicht ist in alkalischem und in carbonatisiertem Beton beständig, sodass nicht rostende Stähle in einem passiven Zustand vorliegen. Die Initiierung von Lochkorrosionserscheinungen ist dagegen auch an nicht rostenden Stählen in Beton möglich. Der korrosionsauslösende Chloridgehalt ist neben dem Gehalt an Legierungselementen (insbesondere dem Chromgehalt) und der Oberflächenbeschaffenheit auch vom Konzentrationsverhältnis von OH“ zu CI“ im Elektrolyten abhängig. Daher ist prinzipiell zu erwarten, dass in karbonatisierten Betonen geringere Chloridgehalte Korrosion initiieren können als in Betonen mit höheren pH-Werten. Dies gilt in besonderem Maße für nicht rostende Betonstähle mit geringen Chromgehalten, wie z. B. Produkte aus dem Werkstoff 1.4003 (X2CrNi12) mit seiner im Vergleich zu den Standardausteniten geringen Beständigkeit. Um den kritischen korrosionsauslösenden Chloridgehalt am Beispiel eines am Markt verfügbaren ferritischen Chromstahls zu bestimmen, wurden an der Bundesanstalt für Materialforschung und -prüfung (BAM) umfangreiche Untersuchungen zu beschleunigten Korrosionsversuchen in alkalischen und karbonatisierten Mörteln durchgeführt. Mittels Laser-induced Breakdown Spectroscopy (LIBS) konnten die korrosionsauslösenden Chloridgehalte im Phasengrenzbereich Betonstahl-Mörtel ermittelt werden. KW - Korrosion KW - Betonstahl KW - Nicht rostender KW - LIBS KW - Chloridgehalt KW - Kritischer PY - 2020 DO - https://doi.org/10.1002/bate.201900077 SN - 0932-8351 VL - 97 IS - 1 SP - 21 EP - 31 PB - Ernst & Sohn CY - Berlin AN - OPUS4-50247 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ebell, Gino T1 - Untersuchungen zur Ermittlung von Ccrit an nichtrostenden "ferritischen" Betonstählen in alkalischen und karbonatisierten Mörteln N2 - Es wurden elektrochemische und LIBS Untersuchungen verwendet um den kritischen Korrosion auslösenden Chloridgehalt in alkalischen und karbonatisierten Mörteln zu ermitteln. Ein deutliche Abhängikeit zwischen pH-Wert und Ccrit konnte dabei festgestellt werden. T2 - Sitzung zum Ccrit von TOP 12 CY - Luzern, Switzerland DA - 19.02.2020 KW - Korrosion KW - LIBS KW - Chloridgehalt KW - Beton PY - 2020 AN - OPUS4-50599 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Brunier-Coulin, F. A1 - Cuéllar, Pablo A1 - Philippe, P. T1 - Generalized Shields criterion for weakly cohesive granular materials N2 - The erosion of natural sediments by a superficial fluid flow is a generic situation in many usual geological or industrial contexts. However, there is still a lack of fundamental knowledge about erosional processes, especially concerning the role of internal cohesion and adhesive stresses on issues such as the critical flow conditions for the erosion onset or the kinetics of soil mass loss. This contribution investigates the influence of cohesion on the surface erosion by an impinging jet flow based on laboratory tests with artificially bonded granular materials. The model samples are made of spherical glass beads bonded either by solid bridges made of resin or by liquid bridges made of a highly viscous oil. To quantify the intergranular cohesion, the capillary forces of the liquid bridges are here estimated by measuring their main geometrical parameters with image-processing techniques and using well-known analytical expressions. For the solid bonds, the adhesive strength of the materials is estimated by direct measurement of the yield tensile forces and stresses at the particle and sample scales, respectively, with specific traction tests developed for this purpose. The proper erosion tests are then carried out in an optically adapted device that permits a direct visualization of the scouring process at the jet apex by means of the refractive index matching technique. On this basis, the article examines qualitatively the kinetics of the scour crater excavation for both scenarios, namely, for an intergranular cohesion induced by either liquid or solid bonds. From a quantitative perspective, the critical condition for the erosion onset is discussed specifically for the case of the solid bond cohesion. In this respect, we propose here a generalized form of the Shields criterion based on a common definition of a cohesion number from yield tensile values, derived at both micro- and macroscales. The article finally shows that the proposed form manages to reconcile the experimental data for cohesive and cohesionless materials, the latter in the form of the so-called Shields curve along with some previous results of the authors which have been appropriately revisited. KW - Hydraulic jet erosion KW - Cohesive granular materials KW - Jet erosion test PY - 2020 DO - https://doi.org/10.1103/PhysRevFluids.5.034308 VL - 5 IS - 3 SP - 034308 PB - American Physical Society AN - OPUS4-50613 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Priebe, Nsesheye Susan A1 - Sturm, Patrick A1 - Kühne, Hans-Carsten A1 - Gluth, Gregor ED - Bishnoi, S. T1 - Comparison of brick clays and a kaolinitic clay regarding calcination and performance in blended cement mortars N2 - Two brick clays (rich in 2:1 clay minerals) and a low-grade kaolinitic clay were studied regarding their transformations during calcination and their performance in blended cement mortars. The mortars with calcined clays exhibited decreased workability (slump flow), but this effect could be mitigated by employment of a conventional superplasticizer; however, compressive strength of the hardened mortar was lowered in some cases. While the kaolinitic clay generally yielded the highest strength, the performance of a brick clay could be increased by grinding to higher fineness and by mixing it with the kaolinitic clay. T2 - 3rd International Conference on Calcined Clays for Sustainable Concrete CY - New Delhi, India DA - 15.10.2019 KW - Calcined clays KW - Blended cements KW - Workability KW - Supplementary cementitious materials PY - 2020 SN - 978-981-15-2805-7 DO - https://doi.org/10.1007/978-981-15-2806-4_10 N1 - Geburtsname von Priebe, Nsesheye Susan: Msinjili, N. S. - Birth name of Priebe, Nsesheye Susan: Msinjili, N. S. VL - 25 SP - 85 EP - 93 PB - Springer CY - Singapore AN - OPUS4-50663 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Zinas, Orestis T1 - Potentials of probabilistic approaches in offshore foundation installation N2 - This presentation discusses the potentials of probabilistic methods in offshore foundation installation, from the perspective of probabilistic ground models and data-driven site characterization. We discuss about methodologies for utilizing site-specific geotechnical (CPT) and geological data, aiming to construct an integrated ground model that can predict stratigraphic profiles and useful for geotechnical design parameters at any location within a 3D domain. The predicted parameters and stratigraphy are then used to predict the probability of potential pile tip damage, upon collision with a boulder. T2 - Colloquium Buckling of Offshore Wind Energy Structures CY - Berlin, Germany DA - 14.02.2024 KW - Wind KW - Offshore KW - Buckling KW - Probabilistic KW - Ground PY - 2024 AN - OPUS4-59538 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Priebe, Nsesheye Susan A1 - Gluth, Gregor A1 - Sturm, Patrick A1 - Vogler, Nico A1 - Kühne, Hans-Carsten T1 - Comparison of calcined illitic clays (brick clays) and low-grade kaolinitic clays as supplementary cementitious materials N2 - The use of calcined clays as supplementary cementitious materials (SCMs) has been identified as a viable option to decrease the CO2 emissions related to cement production. However, while extensive data is available about kaolinitic clays in this context, other clays such as illitic clays appear to be under-studied. Therefore, in the present study, two illitic clays were compared to two low-grade kaolinitic clays in terms of transformations in the calcination temperature range 650–900 °C, and performance of the calcined clays in blended cement pastes as measured by strength evolution, heat release, hydrated phase formation and portlandite consumption. The illitic clays required a higher calcination temperature for complete dehydroxylation of their illite than what is necessary for dehydroxylation of kaolinite. These higher calcination temperatures also led to particle sintering, significantly decreasing the specific surface area of the illitic clays, particularly for the clay with the higher Fe2O3 content. Nevertheless, while the kaolinitic clays generally exhibited the best performance as SCM, the illitic clay with lower Fe2O3 content performed similar to the kaolinitic clays when calcined at optimum temperature and applied at a moderate substitution rate. These findings demonstrate that several different clays have the potential to be used as SCM and indicate possible routes to identify suitable deposits for this purpose. KW - Blended cement KW - Calcined clay KW - Brick clay KW - Illite KW - Kaolinite PY - 2019 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-488195 DO - https://doi.org/10.1617/s11527-019-1393-2 SN - 1359-5997 SN - 1871-6873 N1 - Geburtsname von Priebe, Nsesheye Susan: Msinjili, N. S. - Birth name of Priebe, Nsesheye Susan: Msinjili, N. S. VL - 52 IS - 5 SP - Article Number 94 PB - Springer Nature AN - OPUS4-48819 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Provis, J. L. A1 - Arbi, K. A1 - Bernal, S. A. A1 - Bondar, D. A1 - Buchwald, A. A1 - Castel, A. A1 - Chithiraputhiran, S. A1 - Cyr, M. A1 - Dehghan, A. A1 - Dombrowski-Daube, K. A1 - Dubey, A. A1 - Ducman, V. A1 - Gluth, Gregor A1 - Nanukuttan, S. A1 - Peterson, K. A1 - Puertas, F. A1 - van Riessen, A. A1 - Torres-Carrasco, M. A1 - Ye, G. A1 - Zuo, Y. T1 - RILEM TC 247-DTA round robin test: mix design and reproducibility of compressive strength of alkali-activated concretes N2 - The aim of RILEM TC 247-DTA ‘Durability Testing of Alkali-Activated Materials’ is to identify and validate methodologies for testing the durability of alkali-activated concretes. To underpin the durability testing work of this committee, five alkali-activated concrete mixes were developed based on blast furnace slag, fly ash, and flash-calcined metakaolin. The concretes were designed with different intended performance levels, aiming to assess the capability of test methods to discriminate between concretes on this basis. A total of fifteen laboratories worldwide participated in this round robin test programme, where all concretes were produced with the same mix designs, from single-source aluminosilicate precursors and locally available aggregates. This paper reports the mix designs tested, and the compressive strength results obtained, including critical insight into reasons for the observed variability in strength within and between laboratories. KW - Alkali-activated materials KW - Alkali-activated slag KW - Compressive strength KW - Concrete KW - Mix-design PY - 2019 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-489131 DO - https://doi.org/10.1617/s11527-019-1396-z SN - 1359-5997 SN - 1871-6873 VL - 52 IS - 5 SP - Article Number 99 PB - Springer Nature AN - OPUS4-48913 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Winnefeld, F. A1 - Gluth, Gregor A1 - Bernal, S. A. A1 - Bignozzi, M. C. A1 - Carabba, L. A1 - Chithiraputhiran, S. A1 - Dehghan, A. A1 - Dolenec, S. A1 - Dombrowski-Daube, K. A1 - Dubey, A. A1 - Ducman, V. A1 - Yu, J. A1 - Peterson, K. A1 - Stephan, D. A1 - Provis, J. L. T1 - RILEM TC 247-DTA round robin test: sulfate resistance, alkali-silica reaction and freeze–thaw resistance of alkali-activated concretes N2 - The RILEM technical committee TC 247-DTA ‘Durability Testing of Alkali-Activated Materials’ conducted a round robin testing programme to determine the validity of various durability testing methods, originally developed for Portland cement based-concretes, for the assessment of the durability of alkali-activated concretes. The outcomes of the round robin tests evaluating sulfate resistance, alkali-silica reaction (ASR) and freeze–thaw resistance are presented in this contribution. Five different alkali-activated concretes, based on ground granulated blast furnace slag, fly ash, or metakaolin were investigated. The extent of sulfate damage to concretes based on slag or fly ash seems to be limited when exposed to an Na2SO4 solution. The mixture based on metakaolin showed an excessive, very early expansion, followed by a dimensionally stable period, which cannot be explained at present. In the slag-based concretes, MgSO4 caused more expansion and visual damage than Na2SO4; however, the expansion limits defined in the respective standards were not exceeded. Both the ASTM C1293 and RILEM AAR-3.1 test methods for the determination of ASR expansion appear to give essentially reliable identification of expansion caused by highly reactive aggregates. Alkali-activated materials in combination with an unreactive or potentially expansive aggregate were in no case seen to cause larger expansions; only the aggregates of known very high reactivity were seen to be problematic. The results of freeze–thaw testing (with/without deicing salts) of alkali-activated concretes suggest an important influence of the curing conditions and experimental conditions on the test outcomes, which need to be understood before the tests can be reliably applied and interpreted. KW - Alkali-activated materials KW - Sulfate attack KW - Alkali silica reaction KW - Alkali aggregate reaction KW - Freeze-thaw attack PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-515527 DO - https://doi.org/10.1617/s11527-020-01562-0 VL - 53 IS - 6 SP - 140 PB - Springer Nature AN - OPUS4-51552 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Mundra, Shishir A1 - Provis, J. L. T1 - Mechanisms of passivation and chloride-induced corrosion of mild steel in sulfide-containing alkaline solutions N2 - The pore fluid within many concretes is highly alkaline and rich in reduced sulfur species, but the influence of such alkaline-sulfide solutions on the surface film formed on steel reinforcement is poorly understood. This study investigates the critical role of HS− in defining mild steel passivation chemistry. The surface film formed on the steel in alkaline-sulfide solutions contains Fe(OH)2 and Fe–S complexes, and the critical chloride concentration to induce corrosion increases at high sulfide concentration. However, this behavior is dependent on the duration of exposure of the steel to the electrolyte, and the nature of the sulfidic surface layer. KW - Alkali-activated materials KW - Steel corrosion KW - Sulfide KW - Chloride PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-528861 DO - https://doi.org/10.1007/s10853-021-06237-x VL - 56 IS - 26 SP - 14783 EP - 14802 PB - Springer Nature AN - OPUS4-52886 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Gluth, Gregor A1 - Arbi, K. A1 - Bernal, S. A. A1 - Bondar, D. A1 - Castel, A. A1 - Chithiraputhiran, S. A1 - Dehghan, A. A1 - Dombrowski-Daube, K. A1 - Dubey, A. A1 - Ducman, V. A1 - Peterson, K. A1 - Pipilikaki, P. A1 - Valcke, S. L. A. A1 - Ye, G. A1 - Zuo, Y. A1 - Provis, J. L. T1 - RILEM TC 247-DTA round robin test: carbonation and chloride penetration testing of alkali-activated concretes N2 - Many standardised durability testing methods have been developed for Portland cement-based concretes, but require validation to determine whether they are also applicable to alkali-activated materials. To address this question, RILEM TC 247-DTA ‘Durability Testing of Alkali-Activated Materials’ carried out round robin testing of carbonation and chloride penetration test methods, applied to five different alkali-activated concretes based on fly ash, blast furnace slag or metakaolin. The methods appeared overall to demonstrate an intrinsic precision comparable to their precision when applied to conventional concretes. The ranking of test outcomes for pairs of concretes of similar binder chemistry was satisfactory, but rankings were not always reliable when comparing alkali-activated concretes based on different precursors. Accelerated carbonation testing gave similar results for fly ash-based and blast furnace slag-based alkali-activated concretes, whereas natural carbonation testing did not. Carbonation of concrete specimens was observed to have occurred already during curing, which has implications for extrapolation of carbonation testing results to longer service life periods. Accelerated chloride penetration testing according to NT BUILD 443 ranked the tested concretes consistently, while this was not the case for the rapid chloride migration test. Both of these chloride penetration testing methods exhibited comparatively low precision when applied to blast furnace slag-based concretes which are more resistant to chloride ingress than the other materials tested. KW - Alkali-activated materials KW - Durability KW - Carbonation KW - Chloride penetration KW - Concrete PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-504045 DO - https://doi.org/10.1617/s11527-020-1449-3 SN - 1359-5997 SN - 1871-6873 VL - 53 IS - 1 SP - 21 PB - Springer Nature AN - OPUS4-50404 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kazlagić, Anera A1 - Vogl, Jochen A1 - Gluth, Gregor A1 - Stephan, D. T1 - Provenancing of cement using elemental analyses and isotope techniques – The state-of-the-art and future perspectives N2 - With the aim of identifying the origin and the manufacturer of a cement, a reliable procedure that provides unambiguous results is needed. Such procedure could resolve practical issues in damage research, liability issues and forensic investigations. A substantial number of attempts for fingerprinting of building materials, including cement, has already been carried out during the last decades. Most of them were based on concentration analysis of the main elements/components. This review provides an overview of provenance studies of cement and the main approaches commonly used. Provenance studies of cement via isotope techniques are also presented and discussed as representatives of the state-of-the-art in the field. Due to the characteristic properties and the occurrence of carefully selected isotope ratios, unique fingerprints of different kinds of materials can be provided by these methods. This property has largely been explored in various scientific fields such as geo- and cosmochemistry, food forensics, archaeology, geochronology, biomedical studies, and climate change processes. However, the potential of isotope techniques in cement and concrete research for provenance studies has barely been investigated. Therefore, the review outlines a suitable approach using isotope ratios, which could lead to reliable provenancing of cementitious materials in the future. KW - Cement KW - Sr isotopes KW - Provenance PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-533762 DO - https://doi.org/10.1039/d1ja00144b VL - 36 IS - 10 SP - 2030 EP - 2042 PB - The Royal Society of Chemistry CY - Cambridge, UK AN - OPUS4-53376 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Sturm, Patrick A1 - Moye, J. A1 - Gluth, Gregor A1 - Vogler, Nico A1 - Taffe, A. A1 - Kühne, Hans-Carsten ED - Rossignol, S. ED - Gluth, Gregor T1 - Properties of alkali-activated mortars with salt aggregate for sealing structures in evaporite rock N2 - Concrete structures for sealing of tunnels in the host rock are an essential part of systems for nuclear waste storage. However, concretes based on blended cements or magnesium oxychloride cements, which are commonly considered for this application, can deteriorate severely due to a significant heat of hydration and associated deformation and cracking. Alkali-activated materials (AAMs) offer a potential solution to this problem because of their low heat release during hardening. To explore their suitability for the construction of sealing structures in evaporite rock, various AAMs with salt aggregate were studied regarding fresh properties, heat release, mechanical properties and microstructure. The heat of reaction of the AAMs was up to 55% lower than that of a blended cement designed for sealing structures, indicating significant benefits for the intended application. Other relevant properties such as mechanical strength and permeability depended strongly on the mix-design of the AAMs and curing conditions. KW - Alkali-activated materials KW - Geopolymers KW - Nuclear waste storage KW - Sealing structures KW - Evaporite rock PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-519422 DO - https://doi.org/10.1016/j.oceram.2020.100041 SN - 2666-5395 VL - 5 IS - Special issue: Alkali-activated materials and geopolymers in ceramics and beyond SP - 1 EP - 8 PB - Elsevier CY - Amsterdam AN - OPUS4-51942 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Gluth, Gregor A1 - Ebell, Gino A1 - Hlavacek, Petr A1 - Mietz, Jürgen T1 - Chloride‐induced steel corrosion in alkali‐activated fly ash mortar: Increased propensity for corrosion initiation at defects N2 - Chloride contents at the steel–mortar interface that initiate steel corrosion were determined for carbon steel in alkali‐activated fly ash mortar for three different exposure conditions: exposure to 1 M NaCl solution; leaching in deionized water and then exposure to 1 M NaCl solution; and leaching in deionized water, aging in air at 20°C and natural CO2 concentration, and then exposure to 1 M NaCl solution. For comparison, a Portland cement mortar, exposed to 1 M NaCl solution, was studied. The median values of the corrosion‐initiating chloride contents (average over the full length of the rebar) in the alkali‐activated fly ash mortar varied between 0.35 and 1.05 wt% Cl with respect to binder, consistently lower than what was obtained for the Portland cement mortar, but with no clear trend regarding the exposure conditions. For most of the alkali‐activated fly ash mortar specimens, preferential corrosion at the connection between the working electrode and the external measurement setup was observed, while preferential corrosion did not occur for the Portland cement mortar. Scanning electron microscopy and auxiliary experiments in synthetic solutions indicated that this behavior was caused by inhomogeneities at the steel–mortar interface in the alkali‐activated mortar, likely due to its peculiar rheological properties in the fresh state. KW - Alkali-activated materials KW - Steel corrosion KW - Critical chloride content KW - Steel-concrete interface PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-507268 DO - https://doi.org/10.1002/maco.202011541 VL - 71 IS - 5 SP - 749 EP - 758 PB - Wiley-VCH AN - OPUS4-50726 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hüsken, Götz A1 - Wagner, L.-C. A1 - Gluth, Gregor A1 - Pirskawetz, Stephan A1 - Kühne, Hans-Carsten T1 - Application of Steel Fibres in Alkali-Activated Mortars N2 - Alkali-activated materials are ideal for the repair of concrete structures in harsh environmental conditions due to their high durability in chemically aggressive environments. However, slag-based mortars, in particular, are prone to shrinkage and associated cracks. In this respect, the application of steel fibres is one solution to reduce the formation of shrinkage induced cracks and to improve post cracking behaviour of these mortars. This study investigated the influence of two different types of steel fibres on the tensile properties of two alkali-activated mortars. Direct tensile tests and single fibre pull-outs were performed to analyse the determining failure modes both on macro and micro scale. Mechanical testing was accompanied by non-destructive testing methods such as digital image correlation and acoustic emission for a detailed analysis of the fracture process. T2 - Local Mechanical Properties - LMP 2019 CY - Prague, Czech Republic DA - 06.11.2019 KW - Alkali-activated materials KW - Fibre pull-out KW - Steel fibres KW - Tensile strength PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-509291 UR - https://ojs.cvut.cz/ojs/index.php/APP/article/view/6695 DO - https://doi.org/10.14311/APP.2020.27.0090 VL - 27 SP - 90 EP - 95 CY - Prague, Czech Republic AN - OPUS4-50929 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Henning, Ricky A1 - Sturm, Patrick A1 - Kühne, Hans-Carsten A1 - Keßler, S. A1 - Gluth, Gregor T1 - Untersuchungen zur Wärmeentwicklung von hybriden Zementen N2 - Die Hauptfunktion von Verschlussbauwerken für End- und Zwischenlager von radioaktiven Abfällen besteht in der Erhaltung der geologischen Barriere. Vor allem soll ein potenzieller Stofftransport durch eine möglichst geringe Permeabilität des Bauwerks verhindert bzw. auf vernachlässigbare Werte herabgesetzt werden. Die in-situ-Permeabilität des Verschlussbauwerks steht dabei in direktem Zusammenhang mit dessen Poren- und Makrostruktur, welche bei Bauwerken auf Basis von Beton insbesondere durch Schwind-verformungen und durch thermisch induzierte Rissbildung infolge der Reaktionswärmeentwicklung des Bindemittels gestört werden kann. Die Betone müssen daher neben einer hohen chemischen Langzeitstabilität auch eine geringe bzw. langsame Wärmeentwicklung während der Erhärtungsreaktionen aufweisen. Als hybride Zemente werden Mischungen aus Portlandzement, Betonzusatzstoffen und einem alkalischen Aktivator bezeichnet. Dabei können u. a. Alkalisulfate, Alkalicarbonate, Alkalisilicate und Alkalihydroxide als Aktivatoren zum Einsatz kommen. Aufgrund ihrer hohen chemischen Stabilität im salinaren Milieu sind Betone aus solchen Zementen potenziell besonders gut als Verfüllmaterial für End- und Zwischenlager im Steinsalz geeignet. In der vorliegenden Studie wurden daher hybride Zemente hinsichtlich ihrer Wärmeentwicklung in einem isothermen Kalorimeter sowie hinsichtlich Phasenbestand und Festigkeiten untersucht. Hybride Zementleime wurden auf Basis von Portlandklinker, Hüttensandmehl, Flugasche und Natriumsulfat hergestellt und die Zusammensetzungen systematisch variiert, um den Einfluss der Komponenten auf Wärmeentwicklung, Phasenbestand und mechanische Eigenschaften der Leime zu untersuchen; zusätzlich wurden zu Vergleichszwecken ein Zementleim auf Basis der Betonrezeptur M2 sowie eine alkalisch aktivierte Flugasche untersucht. T2 - 2. Tage der Standortauswahl CY - Online meeting DA - 11.02.2021 KW - Hybride Zemente KW - Hydratationswärme KW - Kalorimetrie PY - 2021 SP - 137 EP - 139 AN - OPUS4-52216 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR ED - Rossignol, S. ED - Gluth, Gregor T1 - Special issue: Alkali-activated materials and geopolymers in ceramics and beyond N2 - Geopolymers and alkali-activated materials have emerged as a complement, and partly as an alternative, to traditional materials in various applications, such as traditional ceramics, energy saving, waste management, building construction, and filtration. These new materials can play an important role in mitigating climate change and promoting a circular economy, which is one of the reasons why they are being actively researched in many laboratories around the world. Open Ceramics, the official, peer-reviewed, Open Access journal of the European Ceramic Society, is dedicated to foster this research and is compiling a Special Issue with the title “Alkali-activated and geopolymer materials in ceramics and various applications”. The aim of this Special Issue is to promote new applications, the use of previously underused raw materials, and in particular a better understanding of the chemical and mechanical behavior of these materials. The scope of the Special Issue includes, but is not limited to, research on the following topics: - valorization of previously underused raw materials - a better understanding of established raw materials - detailed spectroscopic characterization of alkali-activated materials and geopolymers to elucidate their phase assemblage - the mechanism of formation of the phase(s) that comprise these binders - control of their mechanical properties - the effect of fillers/aggregates on their mechanical properties - their durability under various conditions and the underlying deterioration mechanisms - special applications and recycling-related considerations. KW - Alkali-activated materials KW - Geopolymers PY - 2021 UR - https://www.sciencedirect.com/journal/open-ceramics/special-issue/10789KQV7BR SN - 2666-5395 SP - 100013-1 EP - 100184-12 PB - Elsevier CY - Amsterdam AN - OPUS4-51984 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Cuéllar, Pablo T1 - Deep foundations for offshore wind turbines. Part 2: Lateral behaviour and Advanced topics T1 - Cimentaciones profundas para aerogeneradores marinos. Parte 2: Comportamiento lateral y temas avanzados N2 - his presentation deals with the phenomenology and design of pile foundations for offshore wind turbines, and is divided into two lectures. The second lecture continues with the case of laterally loaded offshore piles, which bears most relevance for the case of the monopile foundations. Here again, a clear separation between physical reality and design methods is intended. Finally, the last part of the second lecture introduces several advanced topics which lie outside the classical design approaches, namely the hydromechanical coupling effects (i.e. the excess pore-pressure generation around the monopiles), the cyclic pile fatigue and the so-called pile setup (i.e. the time effects on the axial pile capacity). The relevance of the latter two topics is illustrated with experimental results from a field testing campaign on real large-scale piles. T2 - CEDEX-UNED 2021 Master course on Soil Mechanics and Geotechnical Engineering CY - Online meeting DA - 24.03.2021 KW - Offshore wind energy KW - Deep foundations KW - Offshore geomechanics KW - Lateral load bearing KW - Cyclic degradation KW - Pile ageing PY - 2021 AN - OPUS4-52342 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Cuéllar, Pablo T1 - Deep foundations for offshore wind turbines. Part 1: Axial behaviour T1 - Cimentaciones profundas para aerogeneradores marinos. Parte 1: Comportamiento axial N2 - This presentation deals with the phenomenology and design of pile foundations for offshore wind turbines, and is divided into two lectures. The first lecture presents a brief introduction to the context and peculiarities of such foundations, and then focuses on the particular case of axially loaded piles. This part is most relevant for the relatively slender piles of the multi-pile substructures (i.e. jackets and tripods). A clear distinction between physical phenomenology and practical design is drawn here. T2 - CEDEX-UNED 2021 Master course on Soil Mechanics and Geotechnical Engineering CY - Online meeting DA - 24.03.2021 KW - Offshore wind energy KW - Deep foundations KW - Offshore geomechanics KW - Axial load bearing KW - Design models PY - 2021 AN - OPUS4-52341 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ebell, Gino T1 - Potentialmessung im Stahlbetonbau N2 - Durch das alkalische Porenwassermilieu wird Stahl im Beton durch Ausbildung einer Deckschicht vor Korrosion geschützt. Unter ungünstigen Umgebungsbedingungen (Karbonatisierung, Chlorideintrag) kann die passive Deckschicht auf der Stahloberfläche zerstört werden. Im weiteren Verlauf können sich durch Volumenexpansion der Korrosionsprodukte korrosionsbedingte Folgeschäden, wie Risse und Abplatzungen am Bauwerk ergeben. Um notwendige Sanierungsmaßnahmen sind frühzeitige und weitgehend zerstörungsfrei ermittelte Informationen über das aktuelle Korrosionsverhalten der Stahlbewehrung von großer Bedeutung. Die Potentialfeldmessung ist ein etabliertes und weit verbreitetes Verfahren zur Beurteilung des Korrosionszustandes der Bewehrung in Stahlbetonbauwerken. Mit Hilfe dieses Verfahrens können Bereiche aktiv korrodierender Bewehrung zerstörungsfrei lokalisiert werden. In der Regel kommt diese Messmethode bei der Detektion chloridinduzierter Korrosion zum Einsatz. T2 - KKS-Messtechnik CY - Online meeting DA - 26.04.2021 KW - Korrosion KW - Potentialfeldmessung KW - Corrosion PY - 2021 AN - OPUS4-52529 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Mundra, S. A1 - Furcas, F. E. A1 - Huthwelker, T. A1 - Simon, Sebastian A1 - Borca, C. N. A1 - Provis, J. L. A1 - Gluth, Gregor T1 - Kinetics of Sulfide Oxidation in alkaline solutions studied by X-ray absorption near-edge structure spectroscopy N2 - The oxidation of sulfur in aqueous solutions is an important process in several geochemical and industrial contexts. In concrete technology, it is particularly relevant for the protection of steel reinforcement in slag cement-based concretes, as the presence of sulfides affects the passivation of the steel and corrosion initiation in the presence of chlorides. However, the knowledge about the kinetics of sulfide oxidation in alkaline solutions, such as concrete pore solutions, is incomplete. To address this issue, we prepared solutions with 0.80 M NaOH, and nominally 10, 100 and 350 mM HS−, respectively, and followed the evolution of the sulfur species during bubbling with oxygen-containing gas (concentration 100% or 22%) using X-ray absorption near-edge structure (XANES) spectroscopy at the sulfur K-edge. Polysulfide, thiosulfate, sulfite and sulfate were identified and quantified via linear combination fitting of the spectra, using previously measured standards. A preliminary analysis of the results shows that the initial rate constant of sulfide oxidation depends strongly on the HS− concentration, while it less strongly depending on the oxygen concentration, in line with previous results for lower pH values. Approaches to fit the data to obtain the rate constants of all relevant reactions will be discussed. T2 - 41st Cement & Concrete Science Conference CY - Leeds, Great Britain DA - 12.09.2022 KW - XANES KW - Sulfide oxidation KW - Kinetics PY - 2022 SP - 1 EP - 3 PB - Institute of Materials, Minerals & Mining (IOM3) AN - OPUS4-55650 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ebell, Gino T1 - Entwicklung der Potentialfeldmessung –forschung, Regelwerk, Fortbildung N2 - Ein Übersichtsvortrag zur Entwicklung der Prüfmethode zu einem etablierten und geregelten Messverfahren für die Korrosionszustandsermittlung von Stahlbetonbauwerken. T2 - GfKORR Jahrestagung - Aktuelles aus der Korrosionsforschung - Nutzen und praktische Anwendungen CY - Frankfurt a. M., Germany DA - 08.11.2022 KW - Potentialfeldmessung KW - Korrosion KW - Stahlbeton KW - Korrosionsprüfung PY - 2022 AN - OPUS4-56206 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Cuéllar, Pablo T1 - Deep foundations for offshore wind turbines. Lecture 1: Axial behaviour T1 - Cimentaciones profundas para aerogeneradores marinos - Parte 1: Comportamiento axial N2 - This presentation deals with the phenomenology and design of pile foundations for offshore wind turbines, and is divided into two lectures. The first lecture presents a brief introduction to the context and peculiarities of such foundations, and then focuses on the particular case of axially loaded piles. This part is most relevant for the relatively slender piles of the multi-pile substructures (i.e. jackets and tripods). A clear distinction between physical phenomenology and practical design is drawn here. T2 - Masters course on Soil Mechanics and Geotechnical Engineering. Geotechnical Laboratory of CEDEX CY - Online meeting DA - 21.04.2020 KW - Pile foundations KW - Offshore wind turbines KW - Physical phenomenology KW - Design methods PY - 2020 AN - OPUS4-51057 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Cuéllar, Pablo T1 - Deep foundations for offshore wind turbines. Lecture 2: lateral behaviour and advanced topics T1 - Cimentaciones profundas para aerogeneradores marinos - Parte 2: Comportamiento lateral y tematica avanzada N2 - This presentation deals with the phenomenology and design of pile foundations for offshore wind turbines, and is divided into two lectures. The second lecture continues with the case of lateraly loaded offshore piles, which bears most relevance for the case of the monopile foundations. Here again, a clear separation between physical reality and design methods is intended. Finally, the last part of the second lecture introduces several advanced topics which lie outside the classical design approaches, namely the hydromechanical coupling effects (i.e. the excess pore-pressure generation around the monopiles), the cyclic pile fatigue and the so-called pile setup (i.e. the time effects on the axial pile capacity). The relevance of the latter two topics is illustrated with experimental results from a field testing campaign on real large-scale piles. T2 - Masters course on Soil Mechanics and Geotechnical Engineering. Geotechnical Laboratory of CEDEX CY - Online meeting DA - 21.04.2020 KW - Pile foundations KW - Offshore wind turbines KW - Physical phenomenology KW - Design methods PY - 2020 AN - OPUS4-51059 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Gluth, Gregor T1 - Sulfuric acid resistance of copper-doped and plain metakaolin-based alkali-activated materials studied by 29Si, 27Al and 1H MAS NMR, and Cu K-edge XANES spectroscopy N2 - Alkali-activated materials have been repeatedly reported to exhibit high acid resistance, but no generally accepted hypothesis regarding the underlying mechanisms has emerged yet. To contribute to this issue, K-waterglass-activated metakaolin specimens, with and without the addition of CuSO4·5H2O in the starting mix, were exposed to either a chemically aggressive sewer environment (mortars) or sulfuric acid (pastes). The mode of copper incorporation in the materials and the formation of copper phases in the corroded layers were studied by XANES at the Cu K-edge, and 29Si, 27Al and 1H MAS NMR was employed to understand the processes during acid attack. Copper was found as a spertiniite-like phase in the as-cured materials, while in the deterioration layers of the pastes it was present as copper sulfate. In the corroded regions of the mortars, unequivocal identification of Cu phases was not possible, but the results were reconcilable with the presence of copper carbonate hydroxide. The solid-state NMR results revealed virtually complete dissolution of the K-A-S-H gel and the formation of silica gel, interpreted to be a central mechanism determining the acid resistance. No significant differences between the microstructural alterations of the pastes with and without Cu addition on (chemical) sulfuric acid attack were observed. T2 - 74th RILEM Annual Week & 40th Cement and Concrete Science Conference CY - Online meeting DA - 31.08.2020 KW - Alkali-activated materials KW - Sulfuric acid resistance KW - Sewer structures PY - 2020 AN - OPUS4-51198 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Wagner, Adrian T1 - Ergebnisse der 2. Probenentnahme im Rahmen des Forschungsprojekt es zur Auslagerung von Edel und Duplexstählen in Straßentunneln N2 - Aufgrund der stark korrosiven Atmosphäre in Tunnelbauwerken kommt es aufgrund von Reinigungs- und Sanierungsmaßnahmen an Ein- und Anbauteilen aus nichtrostendem Stahl häufig zu wartungsbedingten Verkehrsbeeinflussungen und Tunnelsperrungen. Bislang ist nur eine kleine Gruppe rostfreier Edelstähle für die Verwendung in Tunnelbauwerken zugelassen. Im Sinne einer mittel- bis langfristigen Reduktion von Wartungsarbeiten besteht jedoch großes Interesse, die Einsatzmöglichkeiten alternativer nichtrostender Stähle zu erhöhen. Ziel ist die Qualifizierung ferritischer-austenitischer Stähle. Erste Untersuchungen nach 2 Jahren Auslagerung zeigten bisher vielversprechende Ergebnisse. T2 - Vorstellung der Ergebnisse bei VDEh in Düsseldorf CY - Online meeting DA - 11.08.2020 KW - Duplex KW - Tunnelbauwerke KW - Korrosion PY - 2020 AN - OPUS4-51109 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ebell, Gino T1 - Ermittlung kritischer Chloridgehalte in Beton mittels LIBS N2 - Es wurden elektrochemische und LIBS Untersuchungen verwendet um den kritischen Korrosion auslösenden Chloridgehalt in alkalischen und karbonatisierten Mörteln zu ermitteln. Ein deutliche Abhängikeit zwischen pH-Wert und Ccrit konnte dabei festgestellt werden. T2 - AK Prüf- und Untersuchungsverfahren CY - Online meeting DA - 18.06.2020 KW - Korrosion KW - Corrosion KW - Ccrit KW - LIBS PY - 2020 AN - OPUS4-50911 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Gluth, Gregor T1 - RILEM TC 281-CCC WG6 - Carbonation of alkali-activated concrete: preliminary results N2 - Preliminary results of RILEM TC 281-CCC Working Group 6 'Carbonation of alkali-activated concrete' are presented. T2 - 74th RILEM Annual Week & 40th Cement and Concrete Science Conference CY - Online meeting DA - 31.08.2020 KW - Alkali-activated materials KW - Carbonation PY - 2020 AN - OPUS4-51199 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ebell, Gino A1 - Burkert, Andreas ED - Isecke, B. ED - Krieger, J. T1 - Detektion korrosionsaktiver Bereiche an Brückenbauwerken aus Stahlbeton mittels Potentialfeldmessung N2 - Durch das alkalische Porenwassermilieu wird Stahl im Beton durch Ausbildung einer Deckschicht vor Korrosion geschützt. Unter ungünstigen Umgebungsbedingungen (Karbonatisierung, Chlorideintrag) kann die passive Deckschicht auf der Stahloberfläche zerstört werden. Im weiteren Verlauf können sich durch Volumenexpansion der Korrosionsprodukte korrosionsbedingte Folgeschäden, wie Risse und Abplatzungen am Bauwerk ergeben. Um notwendige Sanierungsmaß-nahmen sind frühzeitige und weitgehend zerstörungsfrei ermittelte Informationen über das aktuelle Korrosionsverhalten der Stahlbewehrung von großer Bedeutung. Die Potentialfeldmessung ist ein etabliertes und weit verbreitetes Verfahren zur Beurteilung des Korrosionszustandes der Bewehrung in Stahlbetonbauwerken. Mit Hilfe dieses Verfahrens können Bereiche aktiv korrodierender Bewehrung zerstörungsfrei lokalisiert werden. In der Regel kommt diese Messmethode bei der Detektion chloridinduzierter Korrosion zum Einsatz. T2 - 4. Brückenkolloquium CY - Online meeting DA - 08.09.2020 KW - Korrosion KW - Potentialfeldmessung KW - Corrosion PY - 2020 SN - 978-3-8169-3518-6 SN - 978-3-8169-8518-1 SP - 583 EP - 588 PB - expert CY - Tübingen AN - OPUS4-51218 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Baeßler, Matthias T1 - Computational Geomechanics for Offshore Wind N2 - Simulations for the Safety and Efficiency of Foundations in the Offshore Wind Energy Production. T2 - Poster Challenge - EERA JP Wind Online Annual Event 2020 CY - Online meeting DA - 14.09.2020 KW - Numerical simulations KW - Marine geomechanics KW - Offshore wind energy PY - 2020 UR - https://www.eerajpwind.eu/events/eera-jp-wind-setwind-annual-event-2020/ AN - OPUS4-51280 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Priebe, Nsesheye Susan A1 - Vogler, Nico A1 - Sturm, Patrick A1 - Neubert, M. A1 - Schröder, H.-J. A1 - Kühne, Hans-Carsten A1 - Hünger, K.-J. A1 - Gluth, Gregor T1 - Calcined brick clays and mixed clays as supplementary cementitious materials: Effects on the performance of blended cement mortars N2 - While calcined clays in general have been credited with a great potential to mitigate CO2 emissions related to cement production and consumption, calcined brick clays are currently understudied in this regard. In the present work, two brick clays, a low-grade kaolinitic clay, and a mixed clay composed of 50% brick clay and 50% low-grade kaolinitic clay were studied regarding transformations on calcination, and strength and durability performance as well as pore structure of mortars made with the blended cements. All calcined clays exhibited pozzolanic reactivity, with the performance of the brick clays inferior to the low-grade kaolinitic clay. However, the mixed clay performed very similar to the low-grade kaolinitic clay, which points to a viable option for optimal use of brick clays in cementitious systems. The carbonation resistance of the blended cement mortars was generally worse than that of the plain Portland cement mortar, as expected, but the former exhibited a significantly improved chloride penetration resistance. The latter improvement was due to pore structure refinement in the blended cement mortars, compared to the Portland cement mortar. KW - Brick clay KW - Illitic clay KW - Calcined clay KW - Blended cement KW - Supplementary cementitous materials PY - 2021 DO - https://doi.org/10.1016/j.conbuildmat.2020.120990 N1 - Geburtsname von Priebe, Nsesheye Susan: Msinjili, N. S. - Birth name of Priebe, Nsesheye Susan: Msinjili, N. S. VL - 266 SP - 120990 PB - Elsevier Ltd. AN - OPUS4-51362 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Stuff, Maria A1 - Rübner, Katrin A1 - Prinz, Carsten A1 - Rische, N. A1 - Chronz, M. A1 - Kühne, Hans-Carsten ED - Siegesmund, S. ED - Middendorf, B. T1 - Towards a better understanding of tuff stone deterioration N2 - Stone deterioration is the result of a complex interaction of external physical, chemical and biological forces with the mineralogical-petrophysical properties of the stone. With a better understanding of how these properties are linked to material behavior and durability, more effective measures for stone conservation can be developed. Studying these interactions in tuff is particularly complex due to the naturally high heterogeneity of tuff rocks. The first aim of a current research project is to combine the results of recent and older studies on tuff deterioration. Furthermore, the literature overview is complemented by our own investigation of Weibern and Ettringen tuff, with a focus on pore structure characteristics. T2 - STONE - 14th international congress on the deterioration and conservation of stone CY - Meeting was canceled DA - 07.09.2020 KW - Pore structure KW - Weathering KW - Weibern tuff KW - Ettringen tuff PY - 2020 SN - 978-3-96311-172-3 SP - 805 EP - 810 PB - Mitteldeutscher Verlag CY - Halle (Saale) AN - OPUS4-51549 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Cuéllar, Pablo T1 - State of the art and development perspectives of deep foundations for offshore wind converters T1 - Estado del arte y perspectivas de desarrollo de las cimentaciones profundas para aerogeneradores offshore N2 - This presentation provides an overview of the main geotechnical aspects associated with deep foundations in the context of offshore wind generation. The most common deep foundation typologies (large diameter monopiles and multipile typologies) as well as new trends under development (e.g. suction buckets) and their current limits will be briefly described. The talk concludes with a brief review of advanced topics not covered in classical pile design, such as hydromechanical coupling effects (pore pressure generation), cyclic accumulation of deformations, cyclic degradation of axial capacity or pile-setup gains. T2 - Ciclo de Conferencias: Aplicaciones de la Geotecnia en la generación de Energía. Sociedad Argentina de Ingeniería Geotécnica SAIG CY - Online meeting DA - 02.12.2020 KW - Offshore wind energy KW - Deep foundations KW - Offshore geomechanics PY - 2020 AN - OPUS4-51729 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Cuéllar, Pablo T1 - An efficient GPU implementation of a micromechanical computational tool for erosion problems N2 - We present here a set of conceptual and numerical tools for a micromechanical simulation of general erosion problems involving fluid-saturated granular assemblies, whether frictional or cohesive. We propose a parallel computation using graphical processing units (GPUs) to treat large numbers of degrees of freedom with conventional desktop computers. The fluid phase is here simulated with a particle-resolved approach in the frame of the Lattice Boltzmann Method (LBM) while the granular solid phase is modelled as a collection of discrete particles from a Molecular Dynamics DEM perspective. The range of possible material behaviors for the solid granular phase is intended here to cover a broad spectrum from purely frictional to viscous cohesive materials with either brittle or transient debonding features. Specific details of the implementation and some validation cases will be put forward. To conclude we provide some exemplary applications in the field of soil erosion along with details on the parallel performance of the models. The results show that a micromechanical approach can be feasible and useful in practice, providing meaningful insights into complex phenomena like the erosion threshold and kinetics of weakly cemented soils. T2 - EWG-IE 2020 Workshop on "Innovative numerical methods for internal erosion processes" CY - Online meeting DA - 17.12.2020 KW - Erosion KW - Earthen hydraulic constructions KW - Micromechanical modelling KW - LBM-DEM coupling KW - GPU parallel computation PY - 2020 AN - OPUS4-51866 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Seifert, Lando T1 - Prüfung von Spannstählen N2 - Ein Stand zum WIPANO-Projekt Spannstahlsicherheit wurde auf Anfrage in einer Gemeinschaftssitzung des AK "Eisen und Stahl" sowie des AK "Korrosionsuntersuchung und -überwachung" der Gesellschaft für Korrosionsschutz e.V. (GfKORR) präsentiert. Das Projekt hat die Verbesserung der produktspezifischen Prüfnorm ISO 15630-3 als Ziel. Vorgestellt wurden die Wahl der neu entwickelten Wasserstoffbeladung mit galvanostatischer kathodischer Polarisation und die Frage, ob die Prüfung an Lieferoberflächen sinnvoll ist. T2 - Gemeinschaftssitzung des AK "Eisen und Stahl" sowie des AK "Korrosionsuntersuchung und -überwachung" der Gesellschaft für Korrosionsschutz e.V. (GfKORR) CY - Online meeting DA - 23.06.2022 KW - ISO 15630-3 KW - Spannstahl KW - Spannungsrisskorrosion KW - Wasserstoff KW - Permeationsmessung PY - 2022 AN - OPUS4-55105 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Powierza, Bartosz A1 - Stelzner, Ludwig A1 - Oesch, Tyler A1 - Gollwitzer, Christian A1 - Weise, Frank A1 - Bruno, Giovanni T1 - Water migration in one-side heated concrete: 4D in-situ CT monitoring of the moisture-clog-effect N2 - Explosive spalling due to fire exposure in concrete structures can lead severe damage and, in the worst case, to premature component failure. For this reason, an in situ investigation of water Migration in concrete due to surface heating was undertaken. During these experiments, a miniaturized concrete specimen within a confining and insulating double-hull was subjected to surface heating during simultaneous X-ray computed tomography (CT) scanning. Through the use of subtraction-based Image analysis techniques, it was possible to observe and quantify not only drying within areas of the concrete matrix close to the heated surface, but also the migration of moisture to both pore and matrix regions deeper within the specimen. It was also discovered that the correction of CT images for specimen deformation using DVC and variable detector performance using calibrated image filters significantly improved the quality of the results. This clearly demonstrates the potential of X-ray CT for evaluation of other rapid-density-change phenomena in concrete and other building materials. T2 - 8th Conference on Industrial Computed Tomography (iCT 2018) CY - Wels, Austria DA - 06.02.2018 KW - In-Situ X-ray CT KW - Digital Volume Correlation KW - Heated concrete KW - Water migration KW - Fire PY - 2019 DO - https://doi.org/10.1007/s10921-018-0552-7 SN - 1573-4862 SN - 0195-9298 VL - 38 IS - 1 SP - 15, 1 EP - 11 PB - Springer US CY - New York / Heidelberg AN - OPUS4-47147 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Cuéllar, Pablo T1 - Design challenges for Offshore wind-farms. From foundation mechanics to wind-farm aerodynamics N2 - This talk provides a brief introduction on general engineering design challenges for the offshore wind energy production. Some general features of the offshore wind-energy field from a civil engineering perspective are firstly presented, followed by a brief discussion of some of the main geomechanical issues for the foundation of the offshore turbines into the seabed. In the following part, an overview of relevant fluid-structure interactions and some options for an efficient numerical analysis are provided, where the hydromechanical Wave–Tower interaction is firstly discussed. Then, some general aspects of the windfarm aerodynamics are introduced. On the one hand, some modelling possibilities for the wake analysis of single turbines and turbine groups are discussed. And on the other hand the relevance of such analyses for a proper windfarm layout optimization is pointed out. In particular, this talk shows that: i) The bearing capacity of turbine multi-pile foundations can degrade under cyclic loading (waves, wind, …), while for monopile foundations cyclic hydromechanical coupling effects may take place, which may lead to a foundation softening; ii) Numerical analysis of a turbine’s interaction with wind/waves is useful and affordable, while simplified models can already provide a useful insight into the windfarm aerodynamics. iii) Turbulent wake analysis is very relevant for the windfarm layout. T2 - Colloquium "Energy systems compared", Winter semester 20/21, Faculty of Physics CY - Online meeting DA - 21.01.2021 KW - Offshore wind energy KW - Marine geotechnics KW - Fluid-structure interaction KW - Numerical modelling PY - 2021 AN - OPUS4-52038 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Gluth, Gregor A1 - Mundra, Shishir A1 - Henning, Ricky T1 - Chloride binding by layered double hydroxides (LDH/AFm phases) and alkali-activated slag pastes: an experimental study by RILEM TC 283-CAM N2 - Chloride binding by the hydrate phases of cementitious materials influences the rate of chloride ingress into these materials and, thus, the time at which chloride reaches the steel reinforcement in concrete structures. Chloride binding isotherms of individual hydrate phases would be required to model chloride ingress but are only scarcely available and partly conflicting. The present study by RILEM TC 283-CAM ‘Chloride transport in alkali-activated materials’ significantly extends the available database and resolves some of the apparent contradictions by determining the chloride binding isotherms of layered double hydroxides (LDH), including AFm phases (monosulfate, strätlingite, hydrotalcite, and meixnerite), and of alkali-activated slags (AAS) produced with four different activators (Na2SiO3, Na2O·1.87SiO2, Na2CO3, and Na2SO4), in NaOH/NaCl solutions at various liquid/solid ratios. Selected solids after chloride binding were analysed by X-ray diffraction, and thermodynamic modelling was applied to simulate the phase changes occurring during chloride binding by the AFm phases. The results of the present study show that the chloride binding isotherms of LDH/AFm phases depend strongly on the liquid/solid ratio during the experiments. This is attributed to kinetic restrictions, which are, however, currently poorly understood. Chloride binding by AAS pastes is only moderately influenced by the employed activator. A steep increase of the chloride binding by AAS occurs at free chloride concentrations above approx. 1.0 M, which is possibly related to chloride binding by the C–(N–)A–S–H gel in the AAS. KW - Chloride binding KW - Sorption isotherm KW - Layered double hydroxide KW - AFm phase KW - Alkali-activated materials PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-599370 DO - https://doi.org/10.1617/s11527-024-02311-3 SN - 1359-5997 SN - 1871-6873 VL - 57 IS - 4 SP - 1 EP - 17 PB - Springer Nature AN - OPUS4-59937 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Henning, Ricky A1 - Sturm, Patrick A1 - Keßler, S. A1 - Gluth, Gregor ED - Lothenbach, B. ED - Wieland, E. ED - Altmaier, M. T1 - Influence of salt aggregate on the degradation of hybrid alkaline cement (HAC) concretes in magnesium chloride-rich saline solution simulating evaporite rock N2 - Concretes produced from salt aggregate and hybrid alkaline cements, an alkali-activated slag/fly ash blend, or a Portland cement were exposed to a magnesium chloride-rich saline solution ([Mg2+] = 3.6 m, [Cl−] = 8.3 m), representing a solution formed after contact of surface water with evaporite rock (rock salt) in a nuclear waste repository. The hydration and deterioration of the concretes were studied with X-ray diffraction, thermogravimetric analysis, pH mapping and permeability measurements. The results show that calcium silicate hydrate (C-S-H) or sodium-substituted calcium aluminium silicate hydrate (C-N-A-S-H) and Friedel's salt were the major reaction products in the concretes prior to exposure to the saline solution. During exposure to the saline solution, increasing amounts of C-S-H/C-N-A-S-H dissolved, and gypsum and a secondary AFm phase formed. The durability of the concretes improved with increasing amounts of Portland clinker in the cements, due to the associated differences in permeability and chemical resistance. Nevertheless, a massive increase of permeability occurred for all concretes, likely caused by crack formation due to the formation of gypsum from anhydrite in the salt aggregate. Thus, the behavior of the concretes differed from, and was more complex than, the behavior of plain cement pastes. T2 - Joint 6th International Workshop on Mechanisms and Modelling of Waste/Cement Interactions (JCCW 2023) CY - Prague, Czech Republic DA - 20.11.2023 KW - Nuclear waste repository KW - Evaporite rock KW - Magnesium chloride brine KW - Concrete KW - Hybrid alkaline cement PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-599928 DO - https://doi.org/10.1016/j.apgeochem.2024.106027 SN - 0883-2927 SN - 1872-9134 VL - 168 SP - 1 EP - 14 PB - Elsevier AN - OPUS4-59992 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Gluth, Gregor A1 - Bernal, S. A. T1 - RILEM TC CUC: Carbon dioxide uptake by concrete during and after service life – Opening Letter N2 - The ability of cement to chemically bind CO2 in a carbonation reaction enables the material to act as a carbon sink, which could partly account for offsetting the CO2 emissions associated with cement production. In response to the many open questions in this context, the RILEM Technical Committee CUC was created in May 2024. The focus of the TC will be to facilitate discussions regarding the current approaches to estimate the CO2 uptake by cementitious materials (concrete and other construction products) during and after service life. This Opening Letter presents aspects of the motivation to establish the TC, a brief overview of the state of the art in the field, the scheduled work programme, and the anticipated impact of the TC outputs. Though it is not intended to be an exhaustive discussion of the challenges to be addressed, from what is summarized in this letter, it is clear that work is required to base estimates of CO2 uptake by cementitious materials on a data set that is as extensive, accurate and forward-looking as possible. It is anticipated that the inclusion of interdisciplinary perspectives and data from academia and industry will enable progress in the field. KW - Cement KW - Concrete KW - Recarbonation KW - Carbon dioxide uptake KW - Carbonation rate PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-623724 DO - https://doi.org/10.21809/rilemtechlett.2024.208 SN - 2518-0231 VL - 9 SP - 61 EP - 67 PB - RILEM AN - OPUS4-62372 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Gluth, Gregor ED - Rogge, Andreas ED - Meng, Birgit T1 - Dauerhaftigkeit von Betonen auf Basis klimafreundlicher Bindemittel N2 - Aus Gründen des Klimaschutzes werden in den kommenden Jahren mehr Zemente mit verringertem Klinkerfaktor und alternative Bindemittel (klimafreundliche Bindemittel) zum Einsatz kommen. Für ihre sichere und zuverlässige Verwendung ist ein umfangreiches Verständnis der Einflüsse auf die Dauerhaftigkeit der aus ihnen hergestellten Betone notwendig. Der vorliegende Beitrag gibt einen kurzen Überblick über einige jüngere Entwicklungen und Forschungsergebnisse auf dem Gebiet. Der Fokus liegt auf Ergebnissen der Arbeiten von Technischen Komitees der RILEM sowie der EFC und eigenen Forschungsergebnissen. T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM Green Intelligent Building CY - Berlin, Germany DA - 16.10.2024 KW - Klimafreundliche Bindemittel KW - Betone PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-612872 SN - 978-3-9818564-7-7 SP - 22 EP - 29 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-61287 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sittner, Jonathan A1 - Hoffmann, T. A1 - Bertmer, M. A1 - Neubert, M. A1 - Schuster, T. A1 - Gluth, Gregor ED - Rogge, Andreas ED - Meng, Birgit T1 - Optimizing calcination methods towards a more sustainable production of calcined clays N2 - Calcined clays are emerging as sustainable alternatives for cement production due to their potential to reduce carbon footprint and energy consumption. This study investigates the calcination of low-grade kaolinitic clays, using rotary kiln and fluidized bed. The calcined clays from the rotary kiln showed enhanced performance in the cement paste. The fluidized bed method demonstrated the potential for significant energy savings, achieving near-complete dehydroxylation with just 30 minutes of calcination. These findings highlight the promise of fluidized bed calcination for efficient clay activation, though further optimization is needed. T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM Green Intelligent Building CY - Berlin, Germany DA - 16.10.2024 KW - Calcination methods KW - Optimizing KW - Blended cement pastes KW - XRD results KW - Thermogravimetric analysis (TGA) PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-612891 SN - 978-3-9818564-7-7 SP - 37 EP - 45 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-61289 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Gluth, Gregor ED - Rogge, Andreas ED - Meng, Birgit T1 - Alkalisch aktivierte Bindemittel mit hohem Säurewiderstand für die Kanalsanierung N2 - Die biogene Schwefelsäurekorrosion (BSK) von Betonbauteilen in Abwassersystemen verursacht weltweit hohen Reparaturbedarf. Um zukünftigen Reparaturbedarf zu minimieren, werden für Neubau- und Sanierungsmaßnahmen z. T. Materialien mit besonders hohem Widerstand gegen BSK benötigt. Der vorliegende Beitrag beschreibt Forschungen zu alkalisch aktivierten Bindemitteln, die bei geeigneter Formulierung einen hohen Widerstand gegen BSK bzw. Säureangriff aufweisen. Zusätzlich werden jüngste Fortschritte bei der Bewertung von Methoden zur Prüfung des Widerstands gegen BSK dargestellt. T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM Green Intelligent Building CY - Berlin, Germany DA - 16.10.2024 KW - Säurewiderstand KW - Betonbauteile KW - Abwassersystemen PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-613141 SN - 978-3-9818564-7-7 SP - 90 EP - 93 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-61314 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Gluth, Gregor T1 - One-part alkali-activated materials with high sulfuric acid resistance N2 - Materials with a high acid resistance are required in different important infrastructures. Examples include repair systems for sewer structures, where biogenic sulfuric acid corrosion is the major degradation mechanism. Low-calcium alkali-activated materials (AAMs) have been repeatedly observed to exhibit high acid resistance. However, the reasons for the high acid resistance of these materials were not fully under¬stood until recently, and the use of highly alkaline activator solutions to produce AAMs appears to hamper their commercial uptake. These issues have been tackled by characterising one-part AAMs and studying their alteration when exposed to sulfuric acid. One-part AAMs were synthesized by mixing blends of solid silica and sodium aluminate with water, and subsequent curing at 60–80 °C. Acid resistance testing was performed according to DIN 19573, i.e. exposure to sulfuric acid at pH = 1 for 70 days. Characterisation of the cured and the acid-exposed materials was done by XRD, ATR-FTIR, SEM as well as 29Si, 27Al and 1H MAS NMR spectroscopy, including cross-polarisation and double-resonance methods. Materials synthesized from industrial silicas were gel-zeolite composites, containing a substantial amount of unreacted ‘excess’ silica, while materials synthesized from rice husk ash were fully amorphous, containing ‘excess’ hydrous alumina. The sulfuric acid resistance of mortars based on these binders conformed to the requirements of DIN 19573 for sewer repair applications. The high acid resistance was caused by precipitation of silica gel at the mortar–solution interface, inhibiting further degradation. The presence of alumina gel may inhibit bacterial activity, potentially further improving performance in sewer environments. The phase assemblage of silica/sodium aluminate-based one-part AAMs can be adjusted via choice of the silica starting material. Properly designed materials exhibit excellent acid resistance, caused by precipi¬tation of silica gel which protects subjacent regions, and they may also inhibit bacterial activity. T2 - XVI ECerS Conference CY - Turin, Italy DA - 16.06.2019 KW - Alkali-activated materials KW - One-part mix KW - Acid resistance PY - 2019 AN - OPUS4-48236 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ebell, Gino T1 - Potential mapping at concrete structures N2 - Potentialmapping is an electrochemical measurement for the detection of active corroding reinforcement at concrete structures T2 - NDT-E Workshop CY - Berlin, Germany DA - 12.06.20196 KW - Korrosion KW - Potentialfeldmessung KW - Corrosion PY - 2019 AN - OPUS4-48278 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Geißler, Peter A1 - Schwarz, Johannes A1 - Cuéllar, Pablo A1 - Hüsken, Götz A1 - Baeßler, Matthias A1 - Kühne, Hans-Carsten A1 - Morrone, C. T1 - Compaction grouting to improve the pile bearing capacity in non-cohesive soil N2 - The aim of an ongoing research project is to develop a design approach for typical offshore driven piles (e.g. Jacket piles) based on the application of injections by compaction grouting directly at the pile shaft. The paper aims to present the results of laboratory and in-situ tests, which reveal the efficiency and the promising potential of the optimised foundation concept for a more economic dimensioning of pile foundations and to increase their bearing capacity in non-cohesive soil at any moment after installation. T2 - Twenty-ninth International Ocean and Polar Engineering Conference CY - Honolulu, HI, USA DA - 16.06.2019 KW - Offshore Pile Foundation KW - Compaction Grouting KW - Grout KW - Injection Sequence KW - Tensile Capacity PY - 2019 SN - 978-1-880653-85-2 SN - 1098-6189 VL - II SP - 2178 EP - 2184 PB - International Society of Offshore and Polar Engineers (ISOPE) CY - Cupertino, California, USA AN - OPUS4-48505 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kullolli, Borana A1 - Baeßler, Matthias A1 - Cuéllar, Pablo A1 - Rica, S. A1 - Rackwitz, F. T1 - An enhanced interface model for friction fatigue problems of axially loaded piles N2 - The shaft bearing capacity often plays a dominant role for the overall structural behaviour of axially loaded piles in offshore deep foundations. Under cyclic loading, a narrow zone of soil at the pile-soil interface is subject to cyclic shearing solicitations. Thereby, the soil may densify and lead to a decrease of confining stress around the pile due to microphenomena such as particle crushing, migration and rearrangement. This reduction of radial stress has a direct impact on the shaft capacity, potentially leading in extreme cases to pile failure. An adequate interface model is needed in order to model this behaviour numerically. Different authors have proposed models that take typical Interface phenomena in account such as densification, grain breakage, normal pressure effect and roughness. However, as the models become more complex, a great number of material parameters need to be defined and calibrated. This paper proposes the adoption and transformation of an existing soil bulk model (Pastor- Zienkiewicz) into an interface model. To calibrate the new interface model, the results of an experimental campaign with the ring shear device under cyclic loading conditions are here presented. The constitutive model shows a good capability to reproduce typical features of sand behaviour such as cyclic compaction and dilatancy, which in saturated partially-drained conditions may lead to liquefaction and cyclic mobility phenomena. T2 - Conference: OMAE CY - Glasgow, Scotland, UK DA - 09.06.2019 KW - Soil-structure interaction KW - Interface PY - 2019 VL - 2019 SP - Article Number: UNSP V001T10A013 PB - ASME CY - Glasgow, Scotland AN - OPUS4-48444 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kullolli, Borana T1 - An enhanced interface model for friction fatigue problems of axially loaded piles N2 - The shaft bearing capacity often plays a dominant role for the overall structural behaviour of axially loaded piles in offshore deep foundations. Under cyclic loading, a narrow zone of soil at the pile-soil interface is subject to cyclic shearing solicitations. Thereby, the soil may densify and lead to a decrease of confining stress around the pile due to microphenomena such as particle crushing, migration and rearrangement. This reduction of radial stress has a direct impact on the shaft capacity, potentially leading in extreme cases to pile failure. An adequate interface model is needed in order to model this behaviour numerically. Different authors have proposed models that take typical Interface phenomena in account such as densification, grain breakage, normal pressure effect and roughness. However, as the models become more complex, a great number of material parameters need to be defined and calibrated. This paper proposes the adoption and transformation of an existing soil bulk model (Pastor- Zienkiewicz) into an interface model. To calibrate the new interface model, the results of an experimental campaign with the ring shear device under cyclic loading conditions are here presented. The constitutive model shows a good capability to reproduce typical features of sand behaviour such as cyclic compaction and dilatancy, which in saturated partially-drained conditions may lead to liquefaction and cyclic mobility phenomena. T2 - Konferenz CY - Glasgow, Scotland, UK DA - 09.06.2019 KW - Soil-structure interaction KW - Interface PY - 2019 AN - OPUS4-48445 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Cuéllar, Pablo T1 - A GPU-based micromechanical simulation model for submerged geotechnical problems N2 - Driven steel piles are commonly used as deep foundations for a wide range of engineering structures, particularly in the offshore branch. They are also an interesting example among the broad spectrum of geotechnical applications where the fluid-solid interaction at the pore-scale can play a major role for the macromechanical behaviour of the whole system. In the context of the geotechnical practice for offshore wind-farm structures, both the industrial design and the actual dimensions of the large piles used as foundations in the seabed are often driven by factors such as the soil resistance to driving (SRD), which are still not well understood and often estimated based on mere empirical correlations or overly simplified one-dimensional models. In particular, the role of the micromechanical effects during the installation process (e.g. local dilatancy or contractancy) and their consequences on the pore pressure levels at the pile-tip and on the effective resistance to driving, are generally either disregarded or at most assumed to be covered by the simplified engineering “black-box” solutions. Here, we propose a general framework to address such local aspects of a geotechnical application involving fluid-saturated soils while retaining the focus on the micro-scale phenomena. We advocate for an approach that combines the relative simplicity of the Discrete Element Method (DEM) for the solid mechanics with the capabilities of the Lattice Boltzmann Method (LBM) for the fluid dynamics. In this sense, we aim to compile some useful techniques and practical recommendations for an efficient GPU-based implementation of a micromechanical LBM-DEM simulation tool. T2 - DEM8, the 8th International Conference on Discrete Element Methods CY - University Twente, Enschede, The Netherlands DA - 20.07.2019 KW - Offshore geotechnics KW - Micromechanical modelling KW - GPU parallel computation PY - 2019 AN - OPUS4-48588 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Völker, Christoph A1 - Kruschwitz, Sabine A1 - Ebell, Gino T1 - A machine learning‑based data fusion approach for improved corrosion testing N2 - This work presents machine learning-inspired data fusion approaches to improve the non-destructive testing of reinforced concrete. The principal effects that are used for data fusion are shown theoretically. Their effectiveness is tested in case studies carried out on largescale concrete specimens with built-in chloride-induced rebar corrosion. The dataset consists of half-cell potential mapping, Wenner resistivity, microwave moisture and ground penetrating radar measurements. Data fusion is based on the logistic Regression algorithm. It learns an optimal linear decision boundary from multivariate labeled training data, to separate intact and defect areas. The training data are generated in an experiment that simulates the entire life cycle of chloride-exposed concrete building parts. The unique possibility to monitor the deterioration, and targeted corrosion initiation, allows data labeling. The results exhibit an improved sensitivity of the data fusion with logistic regression compared to the best individual method half-cell potential. KW - Corrosion KW - Potential mapping KW - Machine learning PY - 2019 DO - https://doi.org/10.1007/s10712-019-09558-4 SN - 1573-0956 SN - 0169-3298 VL - 41 IS - 3 SP - 531 EP - 548 PB - Springer Nature AN - OPUS4-48799 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Cuéllar, Pablo T1 - Wind energy challenges. An offshore perspective and some possible solutions N2 - This talk provides a brief introduction on general engineering challenges for the offshore (marine) wind energy production, focusing on material, structural and hydromechanical aspects. The talk begins with a broad overview on general trends for offshore wind-farms, with insights on some characteristic structural features and their associated loads. Then, some particular open issues for the foundation of the offshore wind turbines into the seabed are introduced. Here, different research approaches are discussed, from experimental investigations to coupled computational analysis at micro- and macroscopic scales. In the second part of the seminar, both the hydromechanical Wave–Tower interaction and some general aspects of the windfarm aerodynamics (wake analysis) are discussed. Some modelling possibilities in the frame of CFD (computational fluid dynamics) are introduced and the relevance of such analyses for a proper windfarm layout optimization is pointed out. Summing up, this seminar aims to show that: i) Numerical analysis of the turbine’s interaction with wind/waves and with the seabed is both useful and affordable. ii) Simplified models can provide an insight into windfarm aerodynamics. iii) Turbulent wake analysis is very relevant for the windfarm layout. T2 - Bad Honnef Physics School „Energy Science – an interdisciplinary challenge“ CY - Physikzentrum Bad Honnef, Bad Honnef, Germany DA - 01.09.2019 KW - Offshore wind energy KW - Mechanical challenges KW - Offshore foundations KW - Soil-water-structure interaction PY - 2019 AN - OPUS4-48873 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Harnisch, J. T1 - The new DGZfP Specification B12 N2 - The corrosion of steel in reinforced concrete structures is one of the main threats to their durability. Based on the scientific achievements of the past decades the knowledge about the deterioration mechanisms and possible repair strategies for corrosion induced damages have found their way into practice. It is common sense, that a detailed assessment of the structure is the foundation for a successful repair measure. In addition to the “traditional” singular on-site-procedures such as measurement of concrete cover, carbonation depth, half-cell potentials and chloride contents the monitoring of corrosion related parameters has gained in importance over the past few years. The advantages of a corrosion monitoring are obvious. In new buildings, structural elements which cannot be assessed after completion (e.g. tunnel segments), or members with electrically isolating coatings can be monitored by means of integrated sensors providing an insight into the development of crucial parameters such as electrochemical potentials, corrosion currents and the electrical resistivity of the concrete. A less known but very beneficial field of application is the use of corrosion monitoring as an integral part of a repair measure based on principles such as the cathodic protection of steel in concrete (CP) or increasing the electrical resistivity of the concrete (IR). By implementing a corrosion monitoring system, it is possible to survey the time dependent effect of the repair measure on the corrosion process which may lead to a confirmation of successful repair measure or to a modification of the repair strategy. As the principle of cathodic protection for steel in concrete is a recognized repair measure today, the number of applications increases steadily and thus increasing the relevance for corrosion monitoring. Nevertheless, no standards or guidelines concerning the corrosion monitoring are available in Germany today, making it difficult to implement corrosion monitoring in common practice. With this in mind an international task group formed to develop the specification B12 “Corrosion Monitoring of Reinforced and Prestressed Concrete Structures” published by the German Society for Non-Destructive Testing, DGZfP, spring 2018. This paper will present the new specification B12 by highlighting the basic measurement principles and illustrating the potentials of corrosion monitoring for new and existing concrete structures by means of case studies. T2 - SMAR 2019 CY - Potsdam, Germany DA - 27.08.2019 KW - Corrosion KW - Monitoring PY - 2019 AN - OPUS4-48805 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ebell, Gino T1 - Merkblatt B 03 der DGZfP - Ausgabe April 2014 N2 - Das Merkblatt B 03 der Deutschen Gesellschaft für zerstörungsfreie Prüfung gibt dem Anwender und dem Auftraggeber ein Regelwerk an die Hand um eine ordnungsgemäße Potentialfeldmessung beauftragen als auch durchführen zu können. T2 - Lehrgang zur Erlangung der Sachkunde zur Durchführung von Potentialfeldmessungen 2019 CY - Aachen, Germany DA - 24.06.2019 KW - Korrosion KW - Potentialfeldmessung PY - 2019 AN - OPUS4-48800 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ebell, Gino T1 - Inhibition of hydrogen evolution on galvanized reinforcement in fresh concrete by addition of potassium permangante N2 - Due to the EUdirective53/2003/EEC,which has been in force since 17th January, 2005, restricts the soluble chromate content in cements to amaximum value of 2ppm. This ammount is to low to inhibit the hydrogen evolutuion by the cathodic partial reaction in fresh concrete. T2 - Eurocorr 2019 CY - Sevilla, Spain DA - 09.09.2019 KW - Corrosion KW - Galvanized reinforcement KW - Hydrogen PY - 2019 AN - OPUS4-48934 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ebell, Gino T1 - Chloride induced corrosion of steel reinforcement in alkali activated fly ash mortars N2 - Electrochemical investigations to determine the chloride treshhold to induce pitting corrosion at steel reninforcement. T2 - Eurocorr 2019 CY - Sevilla, Spain DA - 09.09.2019 KW - Corrosion KW - Concrete PY - 2019 AN - OPUS4-48935 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hlavacek, Petr A1 - Gluth, Gregor A1 - Lüchtenborg, Jörg A1 - Sturm, Patrick A1 - Mühler, T. A1 - Kühne, Hans-Carsten A1 - Günster, Jens T1 - A Novel Approach to Additive Manufacturing of Alkali-activated Materials: Laser-induced Slip Casting (LIS) of Lithium Aluminate/Silica Slurries N2 - Additive manufacturing of alkali-activated materials currently attracts a lot of attention, because of the possibility to produce customized high-performance elements for a range of applications, potentially being more resource-efficient than conventionally produced parts. Here, we describe a new additive manufacturing process for alkali-activated materials that is based on selective laser-heating of lithium aluminate/microsilica slurries. The new process-material combination allows to manufacture elements with complex geometries at high building rates and high accuracy. The process is versatile and transferrable to structures of sizes differing by orders of magnitude. The mechanical strength of the obtained materials was in the range of values reported for conventional metakaolin-based geopolymers, and superior to what has been hitherto reported for alkali-activated materials produced by additive manufacturing. This mechanical performance was obtained despite the fact that the degree of reaction of the lithium aluminate and the microsilica was low, suggesting that significant reactions took place only at the surface of the microsilica particles. KW - Laser-induced slip casting KW - Alkali-activated materials KW - Additive manufacturing PY - 2019 DO - https://doi.org/10.29272/cmt.2018.0011 SN - 2612-4882 VL - 1 IS - 2 SP - 138 EP - 144 PB - Techna Group AN - OPUS4-49142 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Gluth, Gregor T1 - Einkomponentige alkaliaktivierte Bindemittel und Mörtel mit hohem Schwefelsäure-Widerstand N2 - Einkomponentige alkaliaktivierte Bindemittel (AAB), d. h. AAB, bei denen der Aktivator als Feststoff im Bindemittel vorliegt, weisen Vorteile hinsichtlich der praktischen Anwendung im Bauwesen gegenüber konventionellen AAB auf. Einkomponentige AAB lassen sich als Gemische aus reaktiver Silica und Natriumaluminat herstellen, wobei die Reaktionsprodukte von der eingesetzten Silica und den Verhältnissen Na2O/Al2O3/SiO2/H2O abhängen: Während Mikrosilica und ähnliche Reststoffe zu zeolithreichen Produkten führen, erhält man aus Reisschalenasche vollständig amorphe Gele (sog. «Geopolymere»). Mörtel auf Basis solcher Bindemittel entsprechen den Anforderungen von DIN 19573:2016-03 hinsichtlich des Widerstands gegen Schwefelsäureangriff (Prüfung bei pH = 1 für 70 d) und sind damit potentiell als Reparatursysteme für Abwasserinfrastruktur geeignet. Untersuchungen mittels 29Si-MAS-NMR und 1H-29Si-Kreuzpolarisations(CP)-MAS-NMR sowie REM-Aufnahmen von erhärteten und dem Schwefelsäureangriff ausgesetzten AAB zeigen, dass der hohe Säurewiderstand v. a. auf die Fällung von Silicagel an der Grenzfläche Mörtel/Säure zurückzuführen ist, wodurch der Korrosionsfortschritt in darunterliegenden Schichten verlangsamt wird. T2 - Tagung Bauchemie der GDCh-Fachgruppe Bauchemie CY - Aachen, Germany DA - 30.09.2019 KW - Alkaliaktivierte Bindemittel KW - Biogene Schwefelsäurekorrosion KW - Abwasserinfrastruktur KW - Reparatursysteme PY - 2019 AN - OPUS4-49269 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Cuéllar, Pablo T1 - Erosion and soil mechanics for civil constructions. Applications and opportunities of micromechanical modelling N2 - This presentation provides an overview on general issues related to erosive failures in civil constructions like hydraulic infrastructures and offshore foundations. A brief introduction to the related research activities of BAM in the field of offshore wind energy is first provided, and the general possibilities for micromechanical modelling approaches are outlined. Finally, the ongoing DFG-ANR research project COMET is introduced. T2 - Vortrag am Lehrstuhl "System simulation" an der FAU CY - Friedrich–Alexander University, Erlangen, Germany DA - 16.10.2019 KW - Micromechanical analysis KW - Offshore wind energy foundations KW - Erosion KW - Earthen hydraulic infrastructures PY - 2019 AN - OPUS4-49311 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Baeßler, Matthias T1 - Stability and large deformations of slender structures supported by soil materials N2 - Stabilitätsprobleme und große Deformationen schlanker, vorwiegend stahlbaulicher Strukturen sind in einigen Fällen stark von der Belastung und Stützung der Struktur durch den Baugrund abhängig. Der Vortrag verbindet Forschungsansätze zum Thema. T2 - Colloquium on Geotechnical Engineering CY - KIT Karlsruhe, Germany DA - 26.09.2019 KW - Stability Buckling soil-structure-interaction piles offshore PY - 2019 AN - OPUS4-49162 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Gluth, Gregor A1 - Sturm, Patrick A1 - Greiser, Sebastian A1 - Jäger, Christian A1 - Brouwers, H.J.H. A1 - Kühne, Hans-Carsten T1 - Einkomponentige alkaliaktivierte Bindemittel und Mörtel mit hohem Widerstand gegen Schwefelsäureangriff N2 - Einkomponentige alkaliaktivierte Bindemittel (AAB), d. h. AAB, bei denen der Aktivator als Feststoff im Bindemittel vorliegt, weisen Vorteile hinsichtlich der praktischen Anwendung im Bauwesen gegenüber konventionellen AAB auf. Einkomponentige AAB lassen sich als Gemische aus reaktiver Silica und Natriumaluminat herstellen, wobei die Reaktionsprodukte von der eingesetzten Silica und den Verhältnissen Na2O/Al2O3/SiO2/H2O abhängen: Während Mikrosilica und ähnliche Reststoffe zu zeolithreichen Produkten führen, erhält man aus Reisschalenasche vollständig amorphe Gele (sog. «Geopolymere »). Mörtel auf Basis solcher Bindemittel entsprechen den Anforderungen von DIN 19573:2016-03 hinsichtlich des Widerstands gegen Schwefelsäureangriff (Prüfung bei pH = 1 für 70 d) und sind damit potentiell als Reparatursysteme für Abwasserinfrastruktur geeignet. Untersuchungen mittels 29Si-MAS-NMR und 1H-29Si-Kreuzpolarisations(CP)-MAS-NMR sowie REM-Aufnahmen von erhärteten und dem Schwefelsäureangriff ausgesetzten AAB zeigen, dass der hohe Säurewiderstand v. a. auf die Fällung von Silicagel an der Grenzfläche Mörtel/Säure zurückzuführen ist, wodurch der Korrosionsfortschritt in darunterliegenden Schichten verlangsamt wird. T2 - Tagung Bauchemie der GDCh-Fachgruppe Bauchemie CY - Aachen, Germany DA - 30.09.2019 KW - Alkaliaktivierte Bindemittel KW - Biogene Schwefelsäurekorrosion KW - Abwasserinfrastruktur KW - Reparatursysteme PY - 2019 SP - 107 EP - 113 PB - Gesellschaft Deutscher Chemiker CY - Frankfurt am Main AN - OPUS4-49264 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ebell, Gino T1 - Innovative Korrosionsforschung N2 - Darstellung innovativer, kombinierter Messverfahren zur Bestimmung spezifischer elektrochemischer Kennwerte. T2 - AK Korrosionsschutz im konstruktiven Ingenieurbau CY - Frankfurt am Main, Germany DA - 18.10.2019 KW - Korrosion KW - Corrosion PY - 2019 AN - OPUS4-49329 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ebell, Gino T1 - Korrosion von Stahl in Beton - Korrosionsmonitoring N2 - Korrosion von Stahl in Beton ist oft maßgebend für die Nutzungsdauer von Infrastrukturbauwereken aus Stahlbeton. Um rechtzeitig Instandsetzungsmaßnahmen einleiten zu können bietet sich ein Korrosionsmonitoringkonzept an solchen Bauwerken an. T2 - Verbundtreffen AISTEC CY - Berlin, Germany DA - 24.10.2019 KW - Korrosion KW - Potentialfeldmessung KW - Monitoring PY - 2019 AN - OPUS4-49414 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Benseghier, Z. A1 - Cuéllar, Pablo A1 - Luu, L.-H. A1 - Delenne, J.-Y. A1 - Bonelli, S. A1 - Philippe, P. T1 - Relevance of Free Jet Model for Soil Erosion by Impinging Jets N2 - The surface erosion of soil samples caused by an impinging jet can be analyzed using the jet erosion test (JET), a standard experimental test to characterize the erosion resistance of soils. This paper specifically addresses the flow characteristics of a laminar impinging jet over the irregular surface of granular beds to discuss the pertinence and relevance of commonly used empirical estimations based on a selfsimilar model of a free jet. The JET is here investigated at the microscale with a coupled fluid-particle flow numerical odel featuring the lattice Boltzmann method (LBM) for the fluid phase combined with the discrete element method (DEM) for the mechanical behavior of the solid particles. The hydrodynamics of a laminar plane free jet are confronted with the results from a parametric study of jet impingement, both on solid smooth and fixed granular surfaces, that take into account variations in particle size, distance from jet origin, and jet Reynolds number. The flow characteristics at the bed surface are here quantified, including the maximal values in tangential velocity and wall shear stress, which can be regarded as the major cause of particle detachments under hydrodynamic solicitation. It is shown that the maximal velocity at the impinged surface can be described by the free jet self-similar model, provided that a simple empirical coefficient is introduced. Further, an expression is proposed for the maximal shear stress in laminar conditions, including a Blasius-like friction coefficient that is inversely proportional to the square root of the jet Reynolds number. To conclude, finally, the JET erosion of different cohesionless granular samples is analyzed, confirming that the threshold condition at the onset of granular motion is consistent with the Shields diagram and in close agreement with previous experimental results. KW - Lattice Boltzmann method KW - Soil erosion KW - Discrete element method KW - Laminar flow KW - Jet impingement PY - 2020 DO - https://doi.org/10.1061/(ASCE)HY.1943-7900.0001652 VL - 146 IS - 1 SP - 04019047 PB - ASCE AN - OPUS4-49491 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ebell, Gino A1 - Burkert, Andreas T1 - Korrosionsverhalten von feuerverzinktem Betonstahl in karbonatisierten und chloridhaltigen Mörteln N2 - Der Einsatz von feuerverzinkten Betonstählen in karbonatisiewrten Betonen führt bei reduzierten Betondeckungen zu einer signifikanten Nutzungsdauerverlängerung. Bei einwirken von chloriden kann keine signifikanten Verlängerung der Nutzungsdauer durch feuerverzinkte Betonstähle erzielt werden. T2 - GfKORR Jahrestagung 2019 CY - Frankfurt a.M., Germany DA - 12.11.2019 KW - Korrosion KW - Verzinkter Betonstahl PY - 2019 SP - 65 EP - 76 AN - OPUS4-49613 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hüsken, Götz T1 - Application of Steel Fibres in Alkali-Activated Mortars N2 - Alkali-activated materials are ideal for the repair of concrete structures in harsh environmental conditions due to their high durability in chemically aggressive environments. However, slag-based mortars, in particular, are prone to shrinkage and associated cracks. In this respect, the application of steel fibres is one solution to reduce the formation of shrinkage induced cracks and to improve post cracking behaviour of these mortars. This study investigated the influence of two different types of steel fibres on the tensile properties of two alkali-activated mortars. Direct tensile tests and single fibre pull-outs were performed to analyse the determining failure modes both on macro and micro scale. Mechanical testing was accompanied by non-destructive testing methods such as digital image correlation and acoustic emission for a detailed analysis of the fracture process. T2 - 14th International Conference on Local Mechanical Properties CY - Prague, Czech Republic DA - 06.11.2019 KW - Steel fibres KW - Alkali-activated materials KW - Tensile strength KW - Fibre pull-out PY - 2019 AN - OPUS4-49578 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ebell, Gino T1 - Korrosionsverhalten von feuerverzinktem Betonstahl in karbonatisierten und chloridhaltigen Mörteln N2 - Der Einsatz von feuerverzinkten Betonstählen in karbonatisiewrten Betonen führt bei reduzierten Betondeckungen zu einer signifikanten Nutzungsdauerverlängerung. Bei einwirken von chloriden kann keine signifikanten Verlängerung der Nutzungsdauer durch feuerverzinkte Betonstähle erzielt werden. T2 - GfKORR Jahrestagung 2019 CY - Frankfurt a.M., Germany DA - 12.11.2019 KW - Korrosion KW - Verzinkter Betonstahl PY - 2019 AN - OPUS4-49612 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - RPRT A1 - Hlavacek, Petr A1 - Ebell, Gino A1 - Gluth, Gregor A1 - Reinemann, Stefi A1 - Mietz, Jürgen A1 - Kühne, Hans-Carsten T1 - Betonstahlkorrosion in Geopolymerbetonen bei Angriff von Kohlenstoffdioxid und Chlorid N2 - Der kritische, Korrosion auslösende Chloridgehalt für die Beurteilung der Korrosions-beständigkeit von Betonstahl in Geopolymerbetonen ist von großer Bedeutung für die Dauerhaftigkeitsprognose für bewehrte Elemente aus solchen Materialien. Es sind kaum experimentelle Daten in der Fachliteratur vorhanden und die vorliegenden Werte unterscheiden sich zwischen den Studien erheblich. In diesem Projekt wurde der kritische, Korrosion auslösende Chloridgehalt für Betonstahl (BSt 500) in flugaschebasierten (Ca-armen) Geopolymermörtel für verschiedene Beaufschlagungskombinationen bestimmt: Chloridbeaufschlagung mit 1 M NaCl-Lösung; Auslaugen in entionisiertem Wasser und anschließende Chloridbeaufschlagung im 1 M NaCl-Lösung; Auslaugen in entionisiertem Wasser, Carbonatisierung in Luft bei 20 °C und natürlicher CO2 Konzentration und anschließende Chloridbeaufschlagung mit 1 M NaCl-Lösung. Für Referenz-Zwecke wurde zusätzlich der Korrosion auslösende Chloridgehalt für eine Portland-Zement Mischung bei Auslagerung in 1 M NaCl-Lösung bestimmt. KW - Korrosion KW - Geopolymer PY - 2019 SP - 1 EP - 83 AN - OPUS4-49752 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ebell, Gino T1 - Detektion Korrosionsaktiver Bereiche an Stahlbetonbauwerken mittels Potentialfeldmessung N2 - Die Detektion Korrosionsaktiver Bereiche an Stahlbetonbauwerken mittels Potentialfeldmessung ist ein etabliertes Verfahren zur Planung von Instandsetzungsmaßnahmen. Die richtige Durchführung der Messung ist jedoch Maßgebend ür den Erfol und wird in diesem Vortrag näher erörtert. T2 - KKS-Symposium CY - TAE Esslingen, Germany DA - 14.11.2019 KW - Korrosion KW - Potentialfeldmessung PY - 2019 AN - OPUS4-49650 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Vollpracht, A. A1 - Gluth, Gregor A1 - Rogiers, B. A1 - Uwanuakwa, I. D. A1 - Phung, Q. T. A1 - Villagran Zaccardi, Y. A1 - Thiel, C. A1 - Vanoutrive, H. A1 - Etcheverry, J. M. A1 - Gruyaert, E. A1 - Kamali-Bernard, S. A1 - Kanellopoulos, A. A1 - Zhao, Z. A1 - Martins, I. M. A1 - Rathnarajan, S. A1 - De Belie, N. T1 - Report of RILEM TC 281-CCC: insights into factors affecting the carbonation rate of concrete with SCMs revealed from data mining and machine learning approaches N2 - The RILEM TC 281–CCC ‘‘Carbonation of concrete with supplementary cementitious materials’’ conducted a study on the effects of supplementary cementitious materials (SCMs) on the carbonation rate of blended cement concretes and mortars. In this context, a comprehensive database has been established, consisting of 1044 concrete and mortar mixes with their associated carbonation depth data over time. The dataset comprises mix designs with a large variety of binders with up to 94% SCMs, collected from the literature as well as unpublished testing reports. The data includes chemical composition and physical properties of the raw materials, mix-designs, compressive strengths, curing and carbonation testing conditions. Natural carbonation was recorded for several years in many cases with both indoor and outdoor results. The database has been analysed to investigate the effects of binder composition and mix design, curing and preconditioning, and relative humidity on the carbonation rate. Furthermore, the accuracy of accelerated carbonation testing as well as possible correlations between compressive strength and carbonation resistance were evaluated. One approach to summerise the physical and chemical resistance in one parameter is the ratio of water content to content of carbonatable CaO (w/CaOreactive ratio). The analysis revealed that the w/CaOreactive ratio is a decisive factor for carbonation resistance, while curing and exposure conditions also influence carbonation. Under natural exposure conditions, the carbonation data exhibit significant variations. Nevertheless, probabilistic inference suggests that both accelerated and natural carbonation processes follow a square-root-of-time behavior, though accelerated and natural carbonation cannot be converted into each other without corrections. Additionally, a machine learning technique was employed to assess the influence of parameters governing the carbonation progress in concretes. KW - Carbonation KW - Supplementary cementitious materials KW - Concrete PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-614388 DO - https://doi.org/10.1617/s11527-024-02465-0 SN - 1871-6873 SN - 1359-5997 VL - 57 IS - 9 SP - 1 EP - 33 PB - Springer Nature AN - OPUS4-61438 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Simon, Sebastian A1 - Gluth, Gregor ED - Rossignol, S. ED - Gluth, Gregor T1 - Unraveling the hardening mechanism during laser-induced slip casting of lithium aluminate-microsilica slurry N2 - Additive manufacturing (AM) of alkali-activated materials is a promising method for producing ceramic precursors, construction elements and other parts. A recently introduced AM process is laser-induced slip casting of lithium aluminate/microsilica slurries, which yields parts with excellent mechanical strengths. To clarify the underlying mechanisms, μ-Raman spectroscopy was applied to parts produced by the process, and the dissolution and hydration of lithium aluminate was studied inter alia using conventional and in-situ X-ray diffraction. The results show that significant dissolution of lithium aluminate occurs, particularly at increased temperatures during laser interaction, which leads to an increase of pH and precipitation of an akopovaite-like Li-Al-CO3 layered double hydroxide. The increase of the pH is likely to induce dissolution of the microsilica and possibly formation of a hydrous lithium aluminosilicate gel. These observations explain the strength evolution of the studied parts and can also aid the development and improvement of related AM methods. KW - Alkali-activated materials KW - Additive manufacturing KW - Laser-induced slip casting KW - Lithium KW - Layered double hydroxide PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-520557 DO - https://doi.org/10.1016/j.oceram.2021.100060 SN - 2666-5395 VL - 5 IS - Special issue: Alkali-activated materials and geopolymers in ceramics and beyond SP - 1 EP - 7 PB - Elsevier CY - Amsterdam AN - OPUS4-52055 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Durlo Tambara, Luis Urbano A1 - Hirsch, A. A1 - Dehn, F. A1 - Gluth, Gregor T1 - Carbonation resistance of alkali-activated GGBFS/calcined clay concrete under natural and accelerated conditions N2 - The carbonation resistance of alkali-activated materials (AAMs) is a crucial parameter for their applicability in concrete construction, yet the parameters influencing it are insufficiently understood to date. In the present study, the carbonation resistance of alkali-activated concretes with varying fractions of ground granulated blast furnace slag (GGBFS) and calcined clay (i.e., high, intermediate, and low Ca contents) were assessed under natural and accelerated conditions. Corresponding hardened AAM pastes were studied using X-ray diffraction, thermogravimetry, Raman microscopy, and mercury intrusion porosimetry. The carbonation resistance of the concretes at natural CO2 concentration depended principally on their water/(CaO + MgOeq + Na2Oeq + K2Oeq) ratio. The remaining variability for similar ratios was caused by differences between the pore structures of the AAMs. For concrete with favorable water/(CaO + MgOeq + Na2Oeq + K2Oeq) ratio and pore structure, the carbonation resistance was comparable to that of Portland cement concrete. The relationship between carbonation coefficients obtained under accelerated and natural conditions differed for concretes with high and low fractions of calcined clay, indicating that accelerated carbonation testing is less suitable to study the carbonation of low-Ca AAMs. KW - Alkali-activated materials KW - Carbonation KW - Calcined clay PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-610747 DO - https://doi.org/10.1016/j.conbuildmat.2024.138351 SN - 1879-0526 VL - 449 SP - 1 EP - 14 PB - Elsevier CY - Amsterdam AN - OPUS4-61074 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bernal, S. A. A1 - Dhandapani, Y. A1 - Elakneswaran, Y. A1 - Gluth, Gregor A1 - Gruyaert, E. A1 - Juenger, M. C. G. A1 - Lothenbach, B. A1 - Olonade, K. A. A1 - Sakoparnig, M. A1 - Shi, Z. A1 - Thiel, C. A1 - Van den Heede, P. A1 - Vanoutrive, H. A1 - von Greve-Dierfeld, S. A1 - De Belie, N. A1 - Provis, J. L. T1 - Report of RILEM TC 281-CCC: A critical review of the standardised testing methods to determine carbonation resistance of concrete N2 - The chemical reaction between CO2 and a blended Portland cement concrete, referred to as carbonation, can lead to reduced performance, particularly when concrete is exposed to elevated levels of CO2 (i.e., accelerated carbonation conditions). When slight changes in concrete mix designs or testing conditions are adopted, conflicting carbonation results are often reported. The RILEM TC 281-CCC ‘Carbonation of Concrete with Supplementary Cementitious Materials’ has conducted a critical analysis of the standardised testing methodologies that are currently applied to determine carbonation resistance of concrete in different regions. There are at least 17 different standards or recommendations being actively used for this purpose, with significant differences in sample curing, pre-conditioning, carbonation exposure conditions, and methods used for determination of carbonation depth after exposure. These differences strongly influence the carbonation depths recorded and the carbonation coefficient values calculated. Considering the importance of accurately determining carbonation potential of concrete, not just for predicting their durability performance, but also for determining the amount of CO2 that concrete can re-absorb during or after its service life, it is imperative to recognise the applicability and limitations of the results obtained from different tests. This will enable researchers and practitioners to adopt the most appropriate testing methodologies to evaluate carbonation resistance, depending on the purpose of the conclusions derived from such testing (e. g. materials selection, service life prediction, CO2 capture potential). KW - Concrete KW - Cement KW - Carbonation KW - Testing KW - Standards PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-609364 DO - https://doi.org/10.1617/s11527-024-02424-9 VL - 57 SP - 1 EP - 31 PB - Springer Nature AN - OPUS4-60936 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Vollpracht, A. A1 - Thiel, C. A1 - Zhao, Z. A1 - Villagrán Zaccardi, Y. A. A1 - Cordoba, G. P. A1 - Gluth, Gregor A1 - Vanoutrive, H. A1 - Gruyaert, E. A1 - Kanellopoulos, A. A1 - Mi, R. A1 - De Belie, N. T1 - Carbonation of concrete with SCMs: a data analysis by RILEM TC 281-CCC N2 - The RILEM TC 281–CCC "Carbonation of concrete with supplementary cementitious materials" is studying the effect of supplementary cementitious materials (SCMs) on natural and accelerated carbonation of blended cements. In this context a large database with carbonation depths over time has been set-up with currently 910 concrete and mortar mixes, which have been tested at different curing conditions. The collected data includes information on chemical composition and physical properties of the raw materials, on mix-design, compressive strength, curing and carbonation testing conditions. Data for a large variety of binders (with up to 94 % SCMs) and mix designs (with w/b ratios ranging from 0.26 to 0.75) were collected from the literature and unpublished material testing projects. Natural carbonation was recorded for several years in many cases, and indoor as well as outdoor results are included. However, in this contribution only lab conditions are considered. Carbonation kinetics are investigated considering the binder composition and mix design. Furthermore, the accuracy of accelerated carbonation testing is evaluated. As described in literature, the w/CaOreactive-ratio is a decisive factor for carbonation resistance but curing and exposure conditions influence the results as well. Even with identical test conditions, the scatter is very large. T2 - 16th International Congress on the Chemistry of Cement 2023 (ICCC2023) CY - Bangkok, Thailand DA - 18.09.2023 KW - Carbonation KW - Supplemetary cementitious materials KW - Blended cement KW - Concrete PY - 2023 UR - https://www.iccc-online.org/fileadmin/gruppen/iccc/proceedings/ICCC16_2023_Vol_III.pdf VL - III SP - 360 EP - 363 PB - Thailand Concrete Association AN - OPUS4-58736 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sanayei, Mohammad Hassan A1 - Farhat, A. A1 - Luu, L.-H. A1 - Werner, L. A1 - Rettinger, C. A1 - Philippe, P. A1 - Cuéllar, Pablo T1 - Micromechanical framework for a 3d solid cohesion model - implementation, validation and perspectives N2 - This article presents a solid cohesion model for the simulation of bonded granular assemblies in the frame of 3D discrete element approaches (DEM). A simple viscoplastic cohesion model for 2D geometries is extended to 3D conditions, while its yield criterion is generalized as a hyper-surface in the space of bond solicitations to include torsional moments. The model is then calibrated using experimental results of uniaxial traction at both the microscopic and macroscopic scales with an artificial granular cohesive soil. The paper finally presents some simulated results on the macromechanical sample traction application and briefly discusses the model's current limitations and promising prospects for subsequent works. T2 - VII International Conference on Particle-Based Methods PARTICLES 2021 CY - Hamburg, Germany DA - 04.10.2021 KW - Granular Cohesive Materials KW - DEM KW - Micromechanical Tensile Failure KW - Macromechanical Sample Strength PY - 2021 SP - 1 EP - 10 AN - OPUS4-53716 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sanayei, Mohammad Hassan A1 - Farhat, A. A1 - Luu, Li-Hua A1 - Werner, L. A1 - Rettinger, C. A1 - Philippe, P. A1 - Cuéllar, Pablo T1 - Micromechanical framework for a 3D solid cohesion model - Implemantation, validation and perspectives N2 - This article presents a solid cohesion model for the simulation of bonded granular assemblies in the frame of 3D discrete element approaches (DEM). A simple viscoplastic cohesion model for 2D geometries is extended to 3D conditions, while its yield criterion is generalized as a hyper-surface in the space of bond solicitations to include torsional moments. The model is then calibrated using experimental results of uniaxial traction at both the microscopic and macroscopic scales with an artificial granular cohesive soil. The paper finally presents some simulated results on the macromechanical sample traction application and briefly discusses the model's current limitations and promising prospects for subsequent works. T2 - VII International Conference on Particle-Based Methods PARTICLES 2021 CY - Hamburg, Germany DA - 04.10.2021 KW - Granular Cohesive Materials, KW - DEM KW - Micromechanical Tensile Failure KW - Macromechanical Sample Strength PY - 2021 AN - OPUS4-53726 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Johann, Sergej T1 - HF RFID-based Measurement Comparison for Method Optimization in M2 Concrete and Alkali-Activated Mortars N2 - The internal project "SealWasteSafe" of the Federal Institute for Materials Research and Testing is dedicated to the further improvement in the construction of sealing systems for underground repositories of radioactive waste. Particularly, a multi-sensory concept is developed to ensure quality assurance and continuous long-term monitoring on the engineered barriers. Therefore, beside other measures, the temperature and equilibrium moisture of the construction shall be monitored and respective multi-sensoric monitoring concepts are tested first on the laboratory scale. One focus in this project is on embedded application in alkali-activated mortars (AAM), which results in special requirements for the resistance of the sensors to strongly alkaline environments with up to pH 14. In addition, the ingress of water along cables or at sensor positions is critical for sensors embedded in concrete, as the cable access of the sensor housing is a major weak point. It is therefore advisable to equip wireless high frequent radio frequency identification-based sensors, so called HF RFID sensors (short: RFID), that do not require cable access and thus have a stable and leak-proof sensor housing for long-term monitoring. In this contribution, the results from temperature, moisture and transmitted power monitoring of a AAM and a M2 specimens by means of HF RFID sensor systems are presented. T2 - 35th Danubia - Adria Symposium on Advances in Experimental Mechanics CY - Linz, Austria DA - 21.09.2021 KW - Passive sensor interface KW - RFID KW - Structural Health Monitoring KW - Alkali-Activated Mortars PY - 2021 AN - OPUS4-53398 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schneider, Ronald A1 - Cuéllar, Pablo A1 - Baeßler, Matthias T1 - Probabilistic approaches to the design and assessment of offshore foundations considering spatially varying site conditions N2 - In this contribution, we consider two applications in which probabilistic approaches can potentially complement or enhance the design and assessment of offshore wind turbine foundations. First, we illustrate in a numerical example that probabilistic modelling can be helpful in dealing with chang-es in turbine locations during the planning phase of an offshore wind farm. In this case, spatial probabilistic modelling of the ground conditions enables (a) an inference of the soil properties at the modified turbine location from field data collected at different locations across an offshore wind farm site and (b) an optimisation of further site investigations. Second, we discuss the uncer-tainties and risks associated with the installation of large diameter monopiles in soils with hetero-geneities such as strong layers and/or embedded boulders. Subsequently, we present a concept for modelling, understanding, and managing these risks based on a probabilistic model of the subgrade conditions, monopile, and subgrade-pile-interaction. T2 - 3rd International Conference on Structural Integrity for Offshore Energy Industry (SI 2021) CY - Online meeting DA - 15.11.2021 KW - Probabilistic modelling KW - Spatially varying ground conditions KW - Foundation reliability analysis KW - Monopile installation risks PY - 2022 SN - 978-1-8383226-3-2 SP - 9 EP - 17 AN - OPUS4-54531 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Cuéllar, Pablo T1 - Design challenges for Offshore wind-farms. From foundation mechanics to wind-farm aerodynamics N2 - This talk provides a brief introduction on general engineering design challenges for the offshore wind energy production. Some general features of the offshore wind-energy field from a civil engineering perspective are firstly presented, followed by a brief discussion of some of the main geomechanical issues for the foundation of the offshore turbines into the seabed. In the following part, an overview of relevant fluid-structure interactions and some options for an efficient numerical analysis are provided, where the hydromechanical Wave–Tower interaction is firstly discussed. Then, some general aspects of the windfarm aerodynamics are introduced. On the one hand, some modelling possibilities for the wake analysis of single turbines and turbine groups are discussed. And on the other hand the relevance of such analyses for a proper windfarm layout optimization is pointed out. In particular, this talk shows that: i) The performance and behavior of the turbine's foundation is often conditioned by the appearance of large deformations, fluid couplings and grain-scale phenomena, whereby specific physical testing (both in field and lab conditions) and ad-hoc simulation techniques can provide useful insights for design; ii) Numerical analysis of a turbine’s interaction with wind/waves is already affordable in engineering scales, while simplified models can already provide a useful insight into the windfarm aerodynamics. iii) Turbulent wake analysis is very relevant for the windfarm layout. T2 - Colloquium "Energy systems compared", Winter semester 22/23, Faculty of Physics CY - Duisburg, Germany DA - 24.01.2023 KW - Offshore wind-turbine foundations KW - Water-structure interaction KW - Wind-farm aerodynamics PY - 2023 AN - OPUS4-56888 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ebell, Gino A1 - Seifert, Lando A1 - Müller, Thoralf T1 - Stress corrosion test in thiocyanate solution with galvanostatic current N2 - Prüfung von Spannstählen hinsichtlich ihrer Anfälligkeit gegenüber wasserstoffinduzierter Spannungsrisskorrosion in kürzeren Zeiträumen. Gewährleistung der Dauerhaftigkeit mittels neuartiger elektrochemischer Prüfverfahren und galvanostatischer Kontrolle und Wasserstoffbeladung T2 - Meeting ISO TC17 SC16 WG8 CY - Online meeting DA - 11.01.2023 KW - Hydrogen KW - Corrosion PY - 2023 AN - OPUS4-56854 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Cuéllar, Pablo T1 - Deep foundations for offshore wind turbines - 1st part: axial behavior T1 - Cimentaciones profundas para aerogeneradores marinos. 1a parte: Comportamiento axial N2 - This presentation deals with the phenomenology and design of pile foundations for offshore wind turbines, and is divided into two lectures. The first lecture presents a brief introduction to the context and peculiarities of such foundations, and then focuses on the particular case of axially loaded piles. This part is most relevant for the relatively slender piles of the multi-pile substructures (i.e. jackets and tripods). A clear distinction between physical phenomenology and practical design is drawn here. T2 - Masters course on Soil Mechanics and Geotechnical Engineering. Geotechnical Laboratory of CEDEX CY - Online meeting DA - 17.03.2023 KW - Pile foundations KW - Offshore wind turbines KW - Physical phenomenology KW - Design methods KW - Numerical modelling KW - Physical testing PY - 2023 AN - OPUS4-57176 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Mittermayr, F. A1 - Gluth, Gregor A1 - Grengg, C. A1 - Garbe, U. A1 - Jiang, G. ED - Jiang, G. T1 - Concrete corrosion characterization using advanced microscopic and spectroscopic techniques N2 - The aim of this chapter is to give an overview of basic and advanced state-of-the-art microstructural and spectroscopic analytics to investigate inorganic material corrosion in the context of biochemically aggressive sewers. The chapter covers optical methods, electron beam, X-ray and neutron techniques (SEM, MLA, XRF, XRD, CT, Neutron radiography and tomography), and spectroscopic methods (MAS-NMR, FT-IR, and Raman). For each technique, a short section on the fundamental scientific background of the method precedes and examples of data output from the latter in respect to the corrosion of cementitious materials including reinforced concrete is presented. KW - Cement KW - Concrete KW - Deterioration KW - Spectroscopy KW - Microscopy PY - 2023 SN - 978-3-031-29940-7 SN - 978-3-031-29941-4 DO - https://doi.org/10.1007/978-3-031-29941-4_4 SP - 59 EP - 97 PB - Springer CY - Cham AN - OPUS4-57423 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Grengg, C. A1 - Gluth, Gregor A1 - Mittermayr, F. ED - Jiang, G. T1 - Alkali-activated materials for sewers N2 - This chapter aims to give a brief introduction into the field of alkali activated materials (AAM) and their physicochemical material behavior when exposed to sulfuric acid and in biochemically aggressive sewer environments. Additionally, the differences in material behavior within chemical (abiotic) and microbially induced acid environments are highlighted. Finally, existing data on overall performance of AAM, compared to conventional concrete-based building materials in sewer systems will be discussed. KW - Alkali-activated materials KW - Geopolymers KW - MIC KW - Sewage systems PY - 2023 SN - 978-3-031-29940-7 SN - 978-3-031-29941-4 DO - https://doi.org/10.1007/978-3-031-29941-4_11 SP - 233 EP - 247 PB - Springer CY - Cham AN - OPUS4-57424 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ebell, Gino T1 - Merkblatt B 03 der DGZfP - Ausgabe April 2021 N2 - Durch das alkalische Milieu des Porenwassers im Beton ist der Stahl normalerweise dauerhaft vor Korrosion geschützt. Unter ungünstigen Umgebungsbedingungen (Chlorideintrag, Carbonatisierung) kann die passive Deckschicht auf der Stahloberfläche zerstört werden. Der Korrosionsprozess ist initiiert. Die entstehenden Korrosionsprodukte werden zunächst vom Porengefüge des Betons aufgenommen, ohne dass es zu sichtbaren Schäden am Bauwerk führt. Im fortgeschrittenem Stadium der Korrosion können sich dann Risse und Abplatzungen bilden. Um notwendige Sanierungsmaßnahmen sowohl aus sicherheitstechnischen Gründen als auch aus wirtschaftlichen Erwägungen rechtzeitig einzuleiten, sind frühzeitige und weitestgehend zerstörungsfreie Prüfverfahren zur Ermittlung der aktuellen Korrosionswahrscheinlichkeit der Stahlbewehrung von großer Bedeutung. Deshalb finden Methoden und Verfahren zur laufenden bzw. regelmäßigen Korrosionsüberwachung von Stahlbetonbauwerken ständig größere Beachtung, sowohl im Bereich Forschung und Entwicklung als auch in der Praxis. Die elektrochemische Potentialfeldmessung ist ein etabliertes und weit verbreitetes Verfahren zur Beurteilung des Korrosionszustandes der Bewehrung in Stahlbetonbauwerken. Mit Hilfe dieses Verfahrens können Bereiche korrodierender Bewehrung zerstörungsfrei lokalisiert werden. In der Regel kommt diese Methode bei der Detektion von chloridinduzierter Korrosion zum Einsatz. Der Lehrgang vermittelt den Teilnehmenden in kompakter Form einen zusammenfassenden Überblick über die notwendigen Grundlagen zum Verständnis der Messmethode, der Vorbereitung und Durchführung der Messungen, der notwendigen Begleituntersuchungen sowie der Interpretation der gewonnenen Daten. Der erste Tag ist der theoretischen Ausbildung gewidmet, am zweiten Tag folgt dann die praktische Anwendung der Lerninhalte. Am dritten Tag folgt die Abnahme der praktischen und theoretischen Prüfung zur Erlangung des Sachkundenachweises. T2 - Sachkundelehrgang zur Durchführung von Potentialfeldmessungen CY - Berlin, Germany DA - 24.04.2023 KW - Potentialfeldmessung KW - Korrosion PY - 2023 AN - OPUS4-57495 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Baeßler, Matthias T1 - Large Monopiles: Experimental and numerical investigation of monopile tip buckling during installation as well as of local pile buckling under operational conditions N2 - The research project Verification of Buckling Assessment and Behaviour in Large Monopiles (VERBATIM) focuses on challenges arising due to the ongoing increase of dimensions of monopiles as foundation for offshore wind turbines. This project is focused on two main topics: - Monopile tip buckling during pile installation - Local buckling of embedded piles during operation It is known from previous investigations and experiences in practice that large deformations of a monopile tip during offshore installation works can occur. These large deformations initiated at the tip of the monopile are commonly referred to as “pile tip buckling”. Own research focuses on optimising monopile dimensions to reduce the cost of monopile foundations for offshore wind turbines while preventing pile tip buckling. Buckling of embedded cylindrical shells for offshore structures is a common engineering task. Structures can be analysed using standard software and have been done so in recent studies e.g., Gottschalk. However, the trend towards larger monopile and optimised structures has led to a fundamental need for better and verified models. A main challenge is the submodelling of the structure-soil-interaction. Developing such complex models is one main goal of the VERBATIM project. For both main topics model tests were performed at the laboratories of BAM and TU Berlin. These experimental results were used to verify related numerical models and simulations. T2 - WindEurope CY - Copenhagen, Denmark DA - 25.04.2023 KW - Monopiles KW - Tip Buckling KW - Pile Buckling KW - Foundations KW - Offshore KW - Windenergy PY - 2023 AN - OPUS4-57405 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Henning, Ricky A1 - Sturm, Patrick A1 - Keßler, S. A1 - Gluth, Gregor T1 - Corrosion of hybrid alkaline cements in saline solution simulating evaporite rock – effect of the Portland clinker content N2 - Two hybrid alkaline cements (HAC) based on Portland clinker, ground granulated blast furnace slag (GGBFS), fly ash and sodium sulfate, as well as an alkali-activated GGBFS/fly ash blend and a Portland cement paste were exposed to a saturated saline solution for 70 days. The combined chemical attack of chloride, magnesium and sulfate ions and the associated changes of the phase assemblage of the materials were studied by X-ray diffraction, thermal analysis and spatially resolved X-ray fluorescence spectroscopy. The experimental results revealed dissolution of ettringite, C-N-A-S-H and calcite, and the formation of gypsum, Kuzel's salt and Friedel's salt; thermodynamic modeling indicated the formation of M-S-H. The resistance of the HAC against attack by the saline solution increased with Portland clinker fraction. The capacity of portlandite to maintain pH at values above 10 is found to be a major factor controlling the resistance of HAC against corrosion in the saline solution. KW - Hybrid cements KW - Alkali-activated materials KW - Magnesium chloride KW - Corrosion KW - Salt attack PY - 2023 DO - https://doi.org/10.1016/j.cemconres.2023.107215 SN - 0008-8846 SN - 1873-3948 VL - 172 SP - 1 EP - 14 PB - Elsevier Ltd. AN - OPUS4-57638 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Winkler, Juliette A1 - Beck, M. A1 - Gluth, Gregor ED - Schneider, F. ED - Hehl, K. ED - Heyde, S. T1 - Kurz- und mittelfristige Verbundfestigkeit von alkaliaktivierten Mörteln auf Beton N2 - Ein zentrales Fundament moderner Gesellschaften ist eine intakte Abwasserinfrastruktur. Schäden infolge biogener Schwefelsäurekorrosion von konventionellen Betonen haben jedoch zu einem erheblichen Sanierungsbedarf geführt. Alkaliaktivierte Mörtel besitzen aufgrund eines hohen Säurewiderstands das Potential, einen Beitrag zur langfristigen Lösung dieses Problems zu leisten. Dazu müssen jedoch zunächst die Faktoren, die den Haftverbund zwischen diesen Mörteln und dem Betonsubstrat bestimmen, besser verstanden werden, um die Eigenschaften der Beschichtungssysteme gezielt anpassen und verbessern zu können. Die vorliegende Arbeit liefert hierzu einen Beitrag und zeigt dadurch Wege zu einer technisch machbaren und nachhaltigen Sanierung von Abwasserbauwerken auf. KW - Alkalisch aktivierte Bindemittel KW - Abwassersysteme KW - Reparatursysteme KW - Verbund KW - Dauerhaftigkeit PY - 2022 SN - 978-3-8440-8818-2 SP - 89 EP - 100 CY - Berlin AN - OPUS4-57701 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Gluth, Gregor A1 - Ke, X. A1 - Vollpracht, A. A1 - Weiler, L. A1 - Bernal, S. A. A1 - Cyr, M. A1 - Dombrowski-Daube, K. A1 - Geddes, D. A1 - Grengg, C. A1 - Le Galliard, C. A1 - Nedeljkovic, M. A1 - Provis, J. L. A1 - Valentini, L. A1 - Walkley, B. ED - Jędrzejewska, A. ED - Kanavaris, F. ED - Azenha, M. ED - Benboudjema, F. ED - Schlicke, D. T1 - Carbonation of alkali-activated concretes: effects of compositional parameters and carbonation conditions N2 - The current ability to predict the carbonation resistance of alkali-activated materials (AAMs) is incomplete, partly because of widely varying AAM chemistries and variable testing conditions. To identify general correlations between mix design parameters and the carbonation rate of AAMs, RILEM TC 281-CCC Working Group 6 compiled and analysed carbonation data for alkali-activated concretes and mortars from the literature. For comparison purposes, data for blended Portland cement-based concretes with a high percentage of SCMs (≥66% of the binder) were also included in the database. The results show that the water/CaO ratio is not a reliable indicator of the carbonation rate of AAMs. A better indicator of the carbonation rate of AAMs under conditions approximating natural carbonation is their water/(CaO + MgOeq + Na2Oeq + K2Oeq) ratio, where the index ‘eq’ indicates an equivalent amount based on molar masses. This finding can be explained by the CO2 binding capacity of alkaline-earth and alkali metal ions; the obtained correlation also indicates an influence of the space-filling capability of the binding phases of AAMs, as for conventional cements. However, this ratio can serve only as an approximate indicator of carbonation resistance, as other parameters also affect the carbonation resistance of alkali-activated concretes. In addition, the analysis of the dataset revealed peculiarities of accelerated tests using elevated CO2 concentrations for low-Ca AAMs, indicating that even at the relatively modest concentration of 1% CO2, accelerated testing may lead to inaccurate predictions of their carbonation resistance under natural exposure conditions. T2 - International RILEM Conference on Synergising Expertise towards Sustainability and Robustness of Cement-based Materials and Concrete Structures: SynerCrete 2023 CY - Adamantas, Greece DA - 14.06.2023 KW - Carbonation KW - Alkali-activated materials KW - Mix design PY - 2023 DO - https://doi.org/10.1007/978-3-031-33187-9_94 VL - 2 SP - 1029 EP - 1037 PB - Springer CY - Cham AN - OPUS4-57699 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Ebell, Gino T1 - Materialtechnische Untersuchungen an den Spanndrähten N2 - Wasserstoffinduzierte Spannungsrisskorrosion führt zu Standsicherheitsproblemen an Spannbetonbrückenbauwerken mit hochempfindlichen Spannstählen im Spannblockverfahren. KW - Korrosion KW - Spannstahl KW - Spannungsrisskorrosion PY - 2021 SP - 37 EP - 44 PB - Landesbetrieb Straßenwesen Brandenburg CY - Hoppegarten AN - OPUS4-53501 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sankaran, Shivasarathy A1 - Ebell, Gino T1 - Analyzing the performance of discrete galvanic anode systems using electrochemical investigations N2 - Corrosion of reinforcement is one of the major reasons in questioning the service life of building structures. The application of cathodic protection techniques plays a big role in controlling the corrosion process to ensure a longer service life of building structures. This systematic study compares the efficiency and durability of various discrete galvanic zinc anode systems available in the current market using different criteria for measuring efficiency such as potential measurements, electrolyte resistance measurements and several polarization methods to determine the polarizability of the anodes. The results to validate the performance of long-time exposure of discrete zinc anodes in concrete medium are discussed. T2 - EUROCORR 2021 CY - Online meeting DA - 20.09.2021 KW - Corrosion KW - Cathodic Protection KW - Zinc anodes KW - Electrochemical PY - 2021 AN - OPUS4-53507 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Müller, Thoralf T1 - Projektvorstellung Wipano Vorhaben Spanntahlsicherheit N2 - Das WIPANO-Projekt Spannstahlsicherheit wurde mit aktuellen Ergebnissen im Fachgremium der Gesellschaft für Korrosionsschutz e.V. (GfKORR) im Arbeitskreis Eisen und Stahl vorgestellt. Das Projekt hat die Verbesserung der produktspezifischen Prüfnorm ISO 15630-3 als Ziel. Vorgestellt und diskutiert wurden Aspekte des Oberflächeneinflusses, der Wasserstoffaktivität, Veränderung der Messzelle und die Anpassung des Korrosionstests durch kathodische Polarisierung. T2 - Arbeitskreissitzung des GfKorr-Arbeitskreises Eisen und Stahl CY - Online meeting DA - 08.12.2021 KW - Korrosion KW - Spannstahl KW - Spannbetonbauwerke KW - Spannungsrisskorrosion KW - Wasserstoffversprödung PY - 2021 AN - OPUS4-54084 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ebell, Gino T1 - Corrosion of Steel in Concrete and Corrosion Behavior of Stainless Steel N2 - In order to obtain a statement on the corrosion resistance of stainless steel against pitting corrosion, a well-tested measuring arrangement is required. For this purpose, the so-called ECISS test can be used to determine the critical chloride content. This makes it possible to assess the corrosion resistance of various stainless steels that have different chromium contents. T2 - ISO-TC17-SC16-WG13 Expertensitzung CY - Online meeting DA - 11.01.2022 KW - Corrosion KW - Lochkorrosion KW - Chloride induced corrosion KW - Concrete KW - Stainless steel PY - 2022 AN - OPUS4-54239 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Lehmann, Jens A1 - Ebell, Gino T1 - Erörterung des Messprotoklls N2 - Das für die Potentialfeldmessung in der neusten Ausgabe des Merkblattes B03 der DGZfP erarbeitete Messprotokoll berücksichtigt sowohl en Einsatz, von Stab-, Einrad- oder Vierradelektroden. In diesem Vortrag wird auf alle varianten des Gegenmessen von Bezugselektroden im Einsatz eingegangen, ebenso wie auf das Erfassen der notwendigen Randparameter. T2 - Sachkundelehrgang zur Durchführung von Potentialfeldmessungen 2022 CY - Baruth/Mark, Germany DA - 16.05.2022 KW - Korrosion KW - Potentialfeldmessung PY - 2022 AN - OPUS4-54871 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ebell, Gino T1 - Elektrochemische Messungen N2 - Elektrochemische Messungen könne, richtig angewandt, dazu dienen ein Korrosionssystem ausreichend gut zu beschreiben. Im Bauwesen, speziell bei Stahl in Beton, ist es jedoch ohne Kenntnis der korrodierenden Flächen oft nur möglich zwischen aktiv korrodierenden Bereichen und passiven, als Kathode wirksamen, Bereichen zu differenzieren. T2 - Sachkundelehrgang zur Durchführung von Potentialfeldmessungen 2022 CY - Baruth/Mark, Germany DA - 16.05.2022 KW - Potentialfeldmessung KW - Korrosion PY - 2022 AN - OPUS4-54869 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Moye, Janis T1 - Entwicklung und Charakterisierung von alkalisch aktivierten Mörteln für die Betoninstandsetzung - Robustheits- und Dauerhaftigkeitsbetrachtungen N2 - Für die flächige Instandsetzung von Stahlbetonkonstruktionen kommen nahezu ausschließlich zementgebundene Systeme mit hohem Zementgehalt zum Einsatz (1). Bereits 2008 war die Zementproduktion für 5% des weltweiten, anthropogenen CO2-Ausstoßes verantwortlich (2). Um die prozessbedingten CO2-Emissionen zu senken, wird der Zement bereits durch gewisse Mengen an Sekundärrohstoffen wie Flugasche, Silicastaub oder Hüttensandmehl (Hochofenschlacke) substituiert. Das Potenzial für weitere Modifikationen ist inzwischen begrenzt (3). Zudem ist eine hohe Lebensdauer der Konstruktionen in vielen Anwendungsbereichen nur bedingt realisierbar. Spätestens mit Erreichen der geplanten Nutzungsdauer müssen Stahlbetonkonstruktionen mit zementgebundenen Systemen instandgesetzt werden, was im ökonomischen und ökologischen Sinne keine nachhaltige Lösung darstellt. Die Verwendung neuer Baustoffe wie alkalisch aktivierte Mörtel hält sich bisher in Grenzen (4), sodass die Akzeptanz durch praxisnahe Forschung adressiert werden muss. Vorangegangene Forschungsergebnisse zeigen, dass alkalisch aktivierte Bindemittel vielversprechende technische Eigenschaften besitzen. So zeigen sich im Vergleich zu herkömmlichem Portlandzement ein ausgesprochen wirkungsvoller Verbund zu Stahl und Zementmörtel (5), (6), eine hohe chemische Beständigkeit sowie ein Erfolg versprechendes Abwitterungsverhalten bei Frost-Tau-Wechseln (7). Mit diesen Eigenschaften können alkalisch aktivierte Mörtel einen erheblichen Beitrag zur dauerhaften Betoninstandsetzung leisten und somit durch die verringerten CO2-Emmissionen dem Prinzip des nachhaltigen Bauens gerecht werden. Wichtig für die Produktion im größeren Maßstab ist die Verfügbarkeit der möglichen Reststoffe, um eine CO2-positivere Bilanz abzubilden. Im Zuge des Forschungsvorhabens sollen Rezepturen für Instandsetzungsprodukte entworfen werden, die auf alkalisch aktivierte industrielle Reststoffe zurückgreifen und die Anforderungen an konventionelle Instandsetzungsprodukte erfüllen. Hierzu wurden potenzielle Ausgangs-stoffe mit Natriumcarbonat aktiviert und die Verarbeitbarkeit der Leime sowie die Druckfestigkeiten nach sieben Tagen verglichen. Hüttensandmehl reagiert ausreichend mit diesem Aktivator, was sich mit Ergebnissen von (8) und (9) deckt. Es werden 〖CO〗_3^(2-)-Ionen in das System eingebaut, was zu einer anfänglichen Erstarrung des Gefüges durch die Bildung von Carbonaten (Calcit und Hydrotalcit) führt. Nach einer längeren dormanten Phase bilden sich zusätzlich Hydratphasen, die die Festigkeit weiter erhöhen. Weiterhin ist die chemische Zusammensetzung der Schlacken für die Erhärtung und die späteren Eigenschaften von großer Bedeutung (10), (11), was mit einer Parameterstudie im laufenden Jahr an natriumcarbonataktivierten Schlacken näher betrachtet werden soll. Erkenntnisse aus vergleichenden Versuchen durch (12) bestätigen die Einflussnahme der chemischen Zusammensetzung. Die übrigen Reststoffe konnten mit anderen Aktivatoren (z. B. Natriumsilicat und -hydroxid) zu einer Reaktion angeregt werden. Im Hinblick auf die Akzeptanz der alkalisch aktivierten Bindemittel stellen diese Aktivatoren jedoch bei der Herstellung höhere technische Anforderungen an das Personal und die verwendeten Geräte im Vergleich zur konventionellen Beton- und Mörteltechnik. Die Aktivierung mittels Alkalicarbonaten ermöglicht die Herstellung von Beton bzw. Mörtel nach dem üblichen „just add water“-Prinzip (13). Aktuell wird unter Einbindung einer studentischen Abschlussarbeit eine Rezeptur mit Hüttensandmehl hinsichtlich der Frisch- und Festeigenschaften charakterisiert und einer Referenzmischung – basierend auf Portlandzement – gegenübergestellt. Hieraus resultierende Ergebnisse sollen neben den Erkenntnissen aus den Vorversuchen zur Konferenz vorgestellt und ein Ausblick auf die weitere Forschungsarbeit gegeben werden. T2 - Nachwuchswissenschaftler*innenkonferenz 2022 CY - Brandenburg an der Havel, Germany DA - 11.05.2022 KW - Alternative Bindemittel KW - Alkalische Aktivierung KW - Instandsetzung KW - Realkalisierung PY - 2022 AN - OPUS4-55517 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Lehmann, Jens T1 - Das B 03 - Merkblatt - Übersicht N2 - Der Vortrag gibt eine Übersicht zu den Inhalten des B03 Merkblattes zur Potentialfeldmessung mit praktischen Anwendertipps. T2 - Lehrgang zum Erwerb des Sachkundenachweises zur Durchführung von Potentialfeldmessungen CY - Aachen, Germany DA - 12.09.2022 KW - Potentialfeldmessung KW - Korrosion KW - Stahlbeton KW - Spannbeton PY - 2022 AN - OPUS4-55726 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Benseghier, Z. A1 - Luu, L.-H. A1 - Cuéllar, Pablo A1 - Bonelli, S. A1 - Philippe, P. T1 - On the erosion of cohesive granular soils by a submerged jet: a numerical approach N2 - This paper presents an erosion interpretation of cohesive granular materials stressed by an impinging jet based on the results of a micromechanical simulation model. The numerical techniques are briefly described, relying on a two-dimensional Lattice Boltzmann Method coupled with a Discrete Element Methods including a simple model of solid intergranular cohesion. These are then used to perform a parametric study of a planar jet in the laminar regime impinging the surface of granular samples with different degrees of cohesive strength. The results show the pertinence of using a generalized form of the Shields criterion for the quantification of the erosion threshold, which is valid for cohesionless samples, through empirical calibration, and also for cohesive ones. Furthermore, the scouring kinetics are analysed here from the perspective of a selfsimilar expansion of the eroded crater leading to the identification of a characteristic erosion time and the quantification of the classical erosion coefficient. However, the presented results also challenge the postulate of a local erosion law including erodibility parameters as intrinsic material properties. The paper then reviews the main limitations of the simulation and current interpretation models, and discusses the potential causes for the observed discrepancies, questioning the pertinence of using time-averaged macroscopic relations to correctly describe soil erosion. The paper concludes addressing this question with a complementary study of the presented simulations re-assessed at the particle-scale. The resulting local critical shear stress of single grains reveals a very wide dispersion of the data but nevertheless appears to confirm the general macroscopic trend derived for the cohesionless samples, while the introduction of cohesion implies a significant but systematic quantitative deviation between the microscopic and macroscopic estimates. Nevertheless, the micro data still shows consistently that the critical shear stress does actually vary approximately in linear proportion of the adhesive force. KW - Soil erosion KW - Granular cohesion KW - Lattice Boltzmann Method KW - Discrete Element Method KW - Impinging jet PY - 2023 DO - https://doi.org/10.1007/s10035-022-01289-5 VL - 25 IS - 8 SP - 1 EP - 20 PB - Springer AN - OPUS4-56525 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Gluth, Gregor A1 - Ke, X. A1 - Vollpracht, A. A1 - Bernal, S. A. A1 - Cizer, Ö. A1 - Cyr, M. A1 - Dombrowski-Daube, K. A1 - Geddes, D. A1 - Grengg, C. A1 - Le Galliard, C. A1 - Nedeljkovic, M. A1 - Provis, J. L. A1 - Shi, Z. A1 - Valentini, L. A1 - Walkley, B. ED - Escalante-Garcia, J. I. ED - Castro Borges, P. ED - Duran-Herrera, A. T1 - RILEM TC 281-CCC Working Group 6: Carbonation of alkali activated concrete—preliminary results of a literature survey and data analysis N2 - The current understanding of the carbonation of alkali-activated concretes is ham-pered inter alia by the wide range of binder chemistries used. To overcome some of the limitations of individual studies and to identify general correlations between their mix design parameters and carbonation resistance, the RILEM TC 281-CCC working group 6 compiled carbonation data for alkali-activated concretes and mortars from the literature. For comparison purposes, data for blended Portland cement-based concretes with a high percentage of SCMs (≥ 66 % of the binder) were also included in the database. A preliminary analysis of the database indicates that w/CaO ratio and w/b ratio exert an influence on the carbonation resistance of alkali-activated concretes but, contrary to what has been reported for concretes based on (blended) Portland cements, these are not good indicators of their carbonation resistance when considered individually. A better indicator of the carbonation resistance of alkali-activated concretes under conditions approxi-mating natural carbonation appears to be their w/(CaO + Na2O + K2O) ratio. Furthermore, the analysis points to significant shortcomings of tests at elevated CO2 concentrations for low-Ca alkali-activated concretes, indicating that even at a concentration of 1 % CO2, the outcomes may lead to inaccurate predictions of the carbonation coefficient under natural exposure conditions. T2 - 75th RILEM Annual Week CY - Mérida, Yucatán, Mexico DA - 30.08.2021 KW - Alkali-activated materials KW - Durability KW - Carbonation KW - Testing KW - Concrete PY - 2023 SN - 978-3-031-21734-0 SN - 978-3-031-21735-7 DO - https://doi.org/10.1007/978-3-031-21735-7_72 SN - 2211-0852 SN - 2211-0844 VL - 40 SP - 667 EP - 676 PB - Springer CY - Cham AN - OPUS4-57157 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Cuéllar, Pablo T1 - Deep foundations for offshore wind turbines - 2nd part: lateral behavior & advanced topics T1 - Cimentaciones profundas para aerogeneradores marinos. 2a parte: Comportamiento Lateral + Temática avanzada N2 - This presentation deals with the phenomenology and design of pile foundations for offshore wind turbines, and is divided into two lectures. The second lecture continues with the case of laterally loaded offshore piles, which bears most relevance for the case of the monopile foundations. Here again, a clear separation between physical reality and design methods is intended. Finally, the last part of the second lecture introduces several advanced topics which lie outside the classical design approaches, namely the hydromechanical coupling effects (i.e. the excess pore-pressure generation around the monopiles), the cyclic pile fatigue and the so-called pile setup (i.e. the time effects on the axial pile capacity). The relevance of the latter two topics is illustrated with experimental results from a field testing campaign on real large-scale piles. T2 - Masters course on Soil Mechanics and Geotechnical Engineering. Geotechnical Laboratory of CEDEX CY - Online meeting DA - 17.03.2023 KW - Pile foundations KW - Offshore wind turbines KW - Physical phenomenology KW - Design methods KW - Numerical modelling KW - Physical testing PY - 2023 AN - OPUS4-57178 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ebell, Gino T1 - Merkblatt B 03 der DGZfP - Ausgabe April 2014 N2 - Durch das alkalische Porenwassermilieu ist Stahl im Beton vor Korrosion geschützt. Unter ungünstigen Umgebungsbedingungen (Karbonatisierung, Chlorideintrag) kann die passive Deckschicht auf der Stahloberfläche zerstört werden. Im weiteren Verlauf können sich korrosionsbedingte Folgeschäden, wie Risse und Abplatzungen am Bauwerk ergeben. Um notwendige Sanierungsmaßnahmen sind frühzeitige und weitgehend zerstörungsfrei ermittelte Informationen über das aktuelle Korrosionsverhalten der Stahlbewehrung von großer Bedeutung. Die Potentialfeldmessung ist ein etabliertes und weit verbreitetes Verfahren zur Beurteilung des Korrosionszustandes der Bewehrung in Stahlbetonbauwerken. Mit Hilfe dieses Verfahrens können Bereiche aktiv korrodierender Bewehrung zerstörungsfrei lokalisiert werden. In der Regel kommt diese Messmethode bei der Detektion chloridinduzierter Korrosion zum Einsatz. T2 - Sachkundelehrgang zur Durchführung von Potentialfeldmessungen 2022 CY - Baruth/Mark, Germany DA - 16.05.2022 KW - Korrosion KW - Potentialfeldmessung PY - 2022 AN - OPUS4-54870 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Gluth, Gregor A1 - Sturm, Patrick A1 - Greiser, Sebastian A1 - Jäger, Christian A1 - Kühne, Hans-Carsten ED - Wang, J. ED - Kriven, W. ED - Fey, T. ED - Colombo, P. ED - Weber, W.J. ED - Amoroso, J. ED - Fahrenholtz, W.G. ED - Shimamura, K. ED - Halbig, M. ED - Kirihara, S. ED - Wu, Y. ED - Shurgart, K. T1 - One-part geopolymers and aluminosilicate gel-zeolite composites: factors influencing microstructure and engineering properties N2 - Mixing and curing of geopolymers and related alkali-activated materials without storage and handling of highly alkaline solutions possesses advantages regarding safety and economic viability. One possible approach is to produce these materials from solid silica feedstocks and solid sodium aluminate, and subsequent mixing with water. We present a comparison between geopolymers and aluminosilicate gel-zeolite composites synthesized by this route from different silica feedstocks (by-product silica from chlorosilane production, microsilica, rice husk ash) and with different SiO2/Al2O3 ratios, using results from XRD, NMR, SEM, thermal analysis, mechanical and acid resistance testing. The use of rice husk ash favors formation of a fully amorphous geopolymer with high strength. Utilization of the other silica feedstocks leads to formation of aluminosilicate gel-zeolite composites, the amount and kind of zeolites depending on the feedstock and the SiO2/Al2O3 ratio. These composites show beneficial dehydration behavior, viz. no distinct dehydration step of thermal strain, with the phase assemblage after heating to 1000°C controlled by the starting composition. Mortars produced from both, the geopolymers as well as the composites, exhibit high resistance to sulfuric acid attack, making them promising materials for the construction and the repair of industrial and sewer structures. T2 - 42nd International Conference on Advanced Ceramics and Composites CY - Daytona Beach, FL, USA DA - 21.01.2018 KW - Alkali-activated materials KW - One-part geopolymers KW - Sulfuric acid resistance KW - High-temperature resistance PY - 2019 DO - https://doi.org/10.1002/9781119543381.ch17 VL - 39 IS - 3 SP - 183 EP - 196 PB - John Wiley & Sons AN - OPUS4-47282 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Gluth, Gregor T1 - Nachhaltige Betone: Calcinierte Tone als Zementhauptbestandteil N2 - Der Einsatz von calcinierten Tonen als Zementhauptbestandteil ist ein vielversprechender Weg, die mit der Zementherstellung und -verwendung verbundenen CO2-Emissionen zu senken. Im Vortrag werden die Randbedingungen hierfür sowie Ergebnisse eines aktuellen Vorhabens zur Calcinierung von illitreichen Tonen (Ziegeltonen) und anderen Tonen vorgestellt. T2 - Kolloquium Angewandte Geowissenschaften, Technische Universität Berlin CY - Berlin, Germany DA - 14.01.2019 KW - Calcinierte Tone KW - Dreischichtminerale KW - Metakaolin KW - Puzzolane KW - Metatone PY - 2019 N1 - Geburtsname von Priebe, Nsesheye Susan: Msinjili, N. S. - Birth name of Priebe, Nsesheye Susan: Msinjili, N. S. AN - OPUS4-47198 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Carabba, L. A1 - Masi, G. A1 - Pirskawetz, Stephan A1 - Krüger, Simone A1 - Gluth, Gregor A1 - Bignozzi, M.C. ED - Serdar, M. ED - Stirmer, N. ED - Provis, J. T1 - Thermal properties and steel corrosion in light-weight alkali-activated mortars N2 - This study aims at investigating the use of coal fly ash-based alkali activated mortars as passive fire protection system for steel structures. These systems are used to slow down the temperature rise of the steel substrate in case of fire. In addition, the protective system should guarantee the ability to prevent and/or mitigate steel corrosion phenomena. The behavior of a light-weight mortar was compared to that of a normal-weight mortar. Density and porosity were measured to better characterize the physical properties of the mortars. The degree of protection in case of fire was assessed by performing medium-scale fire tests. Acoustic emission measurements were conducted to analyze cracking phenomena during the high temperature exposure. The corrosion process was evaluated using an electrochemical approach in order to monitor the durability of the developed material. Preliminary results show that a 20 mm-thick layer of light-weight mortar is able to protect the steel substrate from reaching the critical temperature of 500 °C for 38 minutes in case of cellulosic fire. In addition, alkali activated mortars provide protection for carbon steel in presence of aggressive environment (i.e. presence of chlorides). The corrosion resistance is strictly related to the physical properties of the developed mortars. T2 - International Conference on Sustainable Materials, Systems and Structures (SMSS 2019) CY - Rovinj, Croatia DA - 20.03.2019 KW - Fire resistance KW - Steel corrosion KW - Acoustic emission KW - Alkali-activated materials PY - 2019 SN - 978-2-35158-223-7 VL - 1 SP - 125 EP - 132 PB - RILEM Publications CY - Paris AN - OPUS4-47584 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sturm, Patrick A1 - Gluth, Gregor A1 - Brouwers, H.J.H. A1 - Kühne, Hans-Carsten ED - Barcevic, A. ED - Rukavina, M.J. ED - Damjanovic, D. ED - Guadagnini, M. T1 - Shrinkage and bond behaviour of one-part alkali-activated mortars N2 - Mortars for application on concrete, e.g. repair mortars or protective coatings, need to have a durable bond to the substrate. This bond is determined by the adhesion between the two materials and by the differential deformations of the mortar and the substrate. In the present contribution, the hygric deformations (shrinkage/expansion) of novel one-part alkali-activated mortars and their bond to concrete substrates are studied. Shrinkage of the mortars was studied at 50 % r.H., while expansion was studied on mortars stored over an open water surface (> 99% r.H.). The bond behaviour was studied by pull-off tests according to DIN EN 1542 and by optical microscopy. The alkali-activated mortars exhibit hygric deformations much lower than the deformations of an established, commercial mortar for sewer maintenance that was tested as reference in parallel with the alkali-activated mortars. The bond behaviour of the alkali-activated mortars depends strongly on their mix-design and curing. Optical microscopy showed that in the mortars with lower bond strength, cracks developed in the mortar during curing. Mortars with appropriate mix-design and curing did not exhibit cracking, and their pull-off strength (up to >3 MPa) conformed to the requirements of relevant standards. T2 - International Conference on Sustainable Materials, Systems and Structures (SMSS 2019) CY - Rovinj, Croatia DA - 20.03.2019 KW - Alkali-activated materials KW - Repair mortars KW - Sewer repair KW - Hygric deformations KW - Bond strength PY - 2019 SN - 978-2-35158-225-1 VL - 3 SP - 103 EP - 110 PB - RILEM Publications CY - Paris AN - OPUS4-47587 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hlavacek, Petr A1 - Reinemann, Steffi A1 - Gluth, Gregor A1 - Ebell, Gino A1 - Mietz, Jürgen ED - Serdar, M. ED - Stirmer, N. ED - Provis, J. T1 - Behaviour of reinforced alkali-activated fly ash mortars under leaching conditions N2 - Corrosion of steel reinforcement in concrete is one of the major deterioration mechanisms limiting the service life of reinforced concrete structures. While for conventional (Portland cement-based) concretes a great amount of experience exists in this regard, the factors that determine the onset of reinforcement corrosion in alkali-activated materials are incompletely understood yet. One aspect of corrosion protection is leaching and the accompanying changes of the concrete pore solution. In the present study, alkali-activated fly ash mortars with embedded carbon steel rebars were exposed to de-ionised water for periods up to 330 days, and the electrochemical response of the steel (free corrosion potential, polarisation resistance), the alteration of the mortar (ohmic resistance, mechanical strength, pore size distribution) as well as the pore solution composition were monitored. Although substantial alkali leaching was observed, the pH of the pore solution remained at values sufficient to protect the embedded steel from depassivation. The mortar did not exhibit indications of significant deterioration. Thus, the present results suggest that leaching is not critical for protection of steel reinforcement in alkali-activated fly ash mortars and concretes. T2 - International Conference on Sustainable Materials, Systems and Structures (SMSS 2019) CY - Rovinj, Croatia DA - 20.03.2019 KW - Alkali-activated materials KW - Steel corrosion KW - Leaching PY - 2019 SN - 978-2-35158-223-7 VL - 1 SP - 118 EP - 124 PB - RILEM Publications CY - Paris AN - OPUS4-47585 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Cuéllar, Pablo T1 - Deep foundations for offshore wind turbines T1 - Cimentaciones profundas para aerogeneradores marinos N2 - This presentation deals with the phenomenology and design of pile foundations for offshore wind turbines, and is divided into two lectures. The first lecture presents a brief introduction to the context and peculiarities of such foundations, and then focuses on the particular case of axially loaded piles. This part is most relevant for the relatively slender piles of the multi-pile substructures (i.e. jackets and tripods). A clear distinction between physical phenomenology and practical design is drawn here. The second lecture continues with the case of lateraly loaded offshore piles, which bears most relevance for the case of the monopile foundations. Here again, a clear separation between physical reality and design methods is intended. Finally, the last part of the second lecture introduces several advanced topics which lie outside the classical design approaches, namely the hydromechanical coupling effects (i.e. the excess pore-pressure generation around the monopiles), the cyclic pile fatigue and the so-called pile Setup (i.e. the time effects on the axial pile capacity). The relevance of the latter two topics is illustrated with experimental results from a field testing campaign on real large-scale piles. T2 - MASTERS COURSE 2019 CEDEX-UNED: MECÁNICA DEL SUELO E INGENIERÍA GEOTÉCNICA CY - Laboratorio de Geotecnia, CEDEX, Madrid, Spain DA - 25.03.2019 KW - Pile foundations KW - Offshore wind turbines KW - Physical phenomenology KW - Design methods KW - Numerical modelling KW - Physical testing PY - 2019 AN - OPUS4-47624 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Gluth, Gregor T1 - Shrinkage and bond behaviour of one-part alkali-activated mortars N2 - Mortars for application on concrete, e.g. repair mortars or protective coatings, need to have a durable bond to the substrate. This bond is determined by the adhesion between the two materials and by the differential deformations of the mortar and the substrate. In the present contribution, the hygric deformations (shrinkage/expansion) of novel one-part alkali-activated mortars and their bond to concrete substrates are studied. Shrinkage of the mortars was studied at 50 % r.H., while expansion was studied on mortars stored over an open water surface (> 99% r.H.). The bond behaviour was studied by pull-off tests according to DIN EN 1542 and by optical microscopy. The alkali-activated mortars exhibit hygric deformations much lower than the deformations of an established, commercial mortar for sewer maintenance that was tested as reference in parallel with the alkali-activated mortars. The bond behaviour of the alkali-activated mortars depends strongly on their mix-design and curing. Optical microscopy showed that in the mortars with lower bond strength, cracks developed in the mortar during curing. Mortars with appropriate mix-design and curing did not exhibit cracking, and their pull-off strength (up to > 3 MPa) conformed to the requirements of relevant standards. T2 - International Conference on Sustainable Materials, Systems and Structures (SMSS 2019) CY - Rovinj, Croatia DA - 20.03.2019 KW - Alkali-activated materials KW - Bond strength KW - Hygric deformations KW - Repair mortars KW - Sewer repair PY - 2019 AN - OPUS4-47618 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Gluth, Gregor T1 - Investigation of calcined brick clays from Central Germany for use as SCM N2 - The production of Portland cement causes a substantial environmental impact, since the calcination of limestone results in high emissions of carbon dioxide. The use of supplementary cementitious materials such as calcined clays as partial replacement for Portland cement offers a solution to limit this environmental impact. This paper investigates four clays from deposits in central Germany with the aim of obtaining pozzolans for the production of Portland-pozzolana cement. The results obtained show that the calcined clays possess pozzolanic proper¬ties, which differ depending on calcination temperature and the relative amounts of kaolinite and 2:1 clay minerals. T2 - International Conference on Sustainable Materials, Systems and Structures (SMSS 2019) CY - Rovinj, Croatia DA - 20.03.2019 KW - Blended cements KW - Calcined clays KW - Brick clays KW - Supplementary cementititous materials PY - 2019 N1 - Geburtsname von Priebe, Nsesheye Susan: Msinjili, N. S. - Birth name of Priebe, Nsesheye Susan: Msinjili, N. S. AN - OPUS4-47617 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hlavacek, Petr T1 - Behaviour of reinforced alkali-activated fly ash mortars under leaching conditions N2 - Corrosion of steel reinforcement in concrete is one of the major deterioration mechanisms limiting the service life of reinforced concrete structures. While for conventional (Portland cement-based) concretes a great amount of experience exists in this regard, the factors that determine the onset of reinforcement corrosion in alkali-activated materials are incompletely understood yet. One aspect of corrosion protection is leaching and the accompanying changes of the concrete pore solution. In the present study, alkali-activated fly ash mortars with embedded carbon steel rebars were exposed to de-ionised water for periods up to 330 days, and the electrochemical response of the steel (free corrosion potential, polarisation resistance), the alteration of the mortar (ohmic resistance, mechanical strength, pore size distribution) as well as the pore solu¬tion composition were monitored. Although substantial alkali leaching was observed, the pH of the pore solution remained at values sufficient to protect the embedded steel from depassivation. The mortar did not exhibit indications of significant deterioration. Thus, the present results suggest that leaching is not critical for pro¬tec¬tion of steel reinforcement in alkali-activated fly ash mortars and concretes. T2 - International Conference on Sustainable Materials, Systems and Structures (SMSS 2019) CY - Rovinj, Croatia DA - 20.03.2019 KW - Alkali-activated materials KW - Leaching KW - Steel corrosion PY - 2019 AN - OPUS4-47621 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ebell, Gino T1 - Potentialmessung im Stahlbetonbau N2 - Durch das alkalische Porenwassermilieu ist Stahl im Beton vor Korrosion geschützt. Unter ungünstigen Umgebungsbedingungen (Karbonatisierung, Chlorideintrag) kann die passive Deckschicht auf der Stahloberfläche zerstört werden. Im weiteren Verlauf können sich korrosionsbedingte Folgeschäden, wie Risse und Abplatzungen am Bauwerk ergeben. Um notwendige Sanierungsmaßnahmen sind frühzeitige und weitgehend zerstörungsfrei ermittelte Informationen über das aktuelle Korrosionsverhalten der Stahlbewehrung von großer Bedeutung. Die Potentialfeldmessung ist ein etabliertes und weit verbreitetes Verfahren zur Beurteilung des Korrosionszustandes der Bewehrung in Stahlbetonbauwerken. Mit Hilfe dieses Verfahrens können Bereiche aktiv korrodierender Bewehrung zerstörungsfrei lokalisiert werden. In der Regel kommt diese Messmethode bei der Detektion chloridinduzierter Korrosion zum Einsatz. T2 - KKS-Lehrgang CY - TAE Esslingen, Germany DA - 06.05.2019 KW - Korrosion KW - Potentialfeldmessung KW - Corrosion KW - Concrete PY - 2019 AN - OPUS4-47937 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Haacke, Nasrin T1 - Forschungsvorhaben RUNOFF - Aktueller Projektstand N2 - Diese Präsentation stellt das RUNOFF-Projekt vor und legt dabei einen Fokus auf die Zwischenergebnisse der Bewitterungsversuche im Feld (AP3/4) und der Modellversuche im Labormaßstab (AP5). T2 - Projektgruppentreffen Baumetalle Kupfer und Zink CY - Online meeting DA - 05.12.2023 KW - Runoff KW - Dauerhaftigkeit KW - Schwermetalle PY - 2023 AN - OPUS4-59074 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Boschmann Käthler, C. A1 - Angst, U. A1 - Ebell, Gino A1 - Elsener, B. T1 - Chloride-induced reinforcement corrosion in cracked concrete: the influence of time of wetness on corrosion propagation N2 - Literature data on the influence of concrete cracks on corrosion propagation of reinforcing steel are contradictory. This might be due to very different exposure and test conditions but also to a lack of time-resolved data in cyclic wetting–drying exposure. Here, the influence of the environmental conditions on the corrosion rates in cracked concrete is studied experimentally. The results show that the corrosion rate in cracked concrete depends on the duration of wetting and drying phases and the relative humidity (RH) during the drying phase. The lower the ambient RH in the drying phase, the faster the cracks dry, which depresses the corrosion rate in the periods between the wetting events. A model is proposed to estimate corrosion rates in cracked concrete cyclic wetting/drying exposure. KW - Korrosion KW - Corrosion KW - Concrete PY - 2020 DO - https://doi.org/10.1080/1478422X.2020.1789371 SP - 1 EP - 11 PB - Taylor Francis Online CY - London AN - OPUS4-50986 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ebell, Gino T1 - Befestigungsmittel im Bauwesen - Der richtige Werkstoff!? N2 - Die Anforderungen in verschiedenen Fachgebieten des Bauwesens an metallene Befestigungsmittels hinsichtlich des Korrosionsschutzes sind zum einen Abhängig von den verwendeten Werkstoffen und zum anderen von der Korrosivität in der jeweiligen Exposition. Hier wird ein Überblick über die gängigen Werkstoffe als auch Anwendung und Fehlerquellen verschafft T2 - Vorlesung TU-Berlin CY - Berlin, Germany DA - 05.07.2023 KW - Korrosion KW - Korrosionsschutz PY - 2023 AN - OPUS4-57882 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Harnisch, J. A1 - Dauberschmidt, C. A1 - Ebell, Gino A1 - Mayer, T. T1 - The new DGZfP Specification B12 "Corrosion Monitoring of Reinforced Concrete Structures" N2 - The corrosion of steel in reinforced concrete structures is one of the main threats to their durability. Based on the scientific achievements of the past decades the knowledge about the deterioration mechanisms and possible repair strategies for corrosion induced damages have found their way into practice. It is common sense, that a detailed assessment of the structure is the foundation for a successful repair measure. In addition to the “traditional” singular on-site-procedures such as measurement of concrete cover, carbonation depth, half-cell potentials and chloride contents the monitoring of corrosion related parameters has gained in importance over the past few years. The advantages of a corrosion monitoring are obvious. In new buildings, structural elements which cannot be assessed after completion (e.g. tunnel segments), or members with electrically isolating coatings can be monitored by means of integrated sensors providing an insight into the development of crucial parameters such as electrochemical potentials, corrosion currents and the electrical resistivity of the concrete. A less known but very beneficial field of application is the use of corrosion monitoring as an integral part of a repair measure based on principles such as the cathodic protection of steel in concrete (CP) or increasing the electrical resistivity of the concrete (IR). By implementing a corrosion monitoring system, it is possible to survey the time dependent effect of the repair measure on the corrosion process which may lead to a confirmation of successful repair measure or to a modification of the repair strategy. As the principle of cathodic protection for steel in concrete is a recognized repair measure today, the number of applications increases steadily and thus increasing the relevance for corrosion monitoring. Nevertheless, no standards or guidelines concerning the corrosion monitoring are available in Germany today, making it difficult to implement corrosion monitoring in common practice. With this in mind an international task group formed to develop the specification B12 “Corrosion Monitoring of Reinforced and Prestressed Concrete Structures” published by the German Society for Non-Destructive Testing, DGZfP, spring 2018. This paper will present the new specification B12 by highlighting the basic measurement principles and illustrating the potentials of corrosion monitoring for new and existing concrete structures by means of case studies. T2 - SMAR 2019 CY - Potsdam, Germany DA - 27.08.2019 KW - Monitoring KW - Corrosion KW - Concrete structures PY - 2019 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-487980 SP - We.4.A.1, 1 PB - SMAR 2019 AN - OPUS4-48798 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schwarz, W. A1 - Wilsch, Gerd A1 - Katsumi, N. A1 - Ebell, Gino A1 - Völker, Tobias T1 - Ion distribution in concrete overlay, mapped by laser induced breakdown spectroscopy (LIBS), modified by an embedded zinc anode N2 - Galvanic corrosion protection by embedded zinc anodes is an accepted technique for the corrosion protection of reinforcing steel in concrete. Galvanic currents flow between the zinc anode and the steel reinforcement due to the potential difference that is in the range of a few hundred mV. The ion distribution was studied on two steel reinforced concrete specimens admixed with 3 wt.% chloride/wt. cement and galvanically protected by a surface applied EZ-anode. On both specimens, a zinc anode was embedded and glued to the concrete surface by a geo-polymer-based chloride-free binder. At one specimen, the EZ-anode was operated for 2,5 years, the EZ-anode at the other specimen was not electrically connected to the reinforcement, this specimen serves as a reference. Both specimens have been stored under identical conditions. The ion distribution between the anode (EZ-ANODE) and cathode (steel reinforcement) was studied by laser-induced breakdown spectroscopy (LIBS) after 7 months, 12 months, and 2,5 years. Results of the LIBS studies on the specimen with activated EZ-anode after 7 months, 12 months, and 2,5 years and of the reference specimen after 2,5 years are reported. Results show that diffusion of ions contributes to the changes in the ion distribution but migration, especially of chlorides towards the EZ-anode is significant despite the weak electric field – several hundred millivolts - generated by the galvanic current. Results show that chloride ions accumulate near the zinc-anode as in water-insoluble zinc-hydroxy chlorides - Simonkollite. T2 - ICCRRR 2022 CY - Capetown, South Africa KW - Corrosion KW - LIBS KW - Zinc KW - Anode PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-560576 DO - https://doi.org/10.1051/matecconf/202236404023 SN - 2261-236X VL - 364 SP - 1 EP - 7 PB - EDP Sciences CY - Les Ulis AN - OPUS4-56057 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Heyn, A. A1 - Meist, M. A1 - Michael, O. A1 - Babutzka, M. A1 - Valet, Svenja A1 - Ebell, Gino T1 - Electrochemical characterization of surfaces of galvanized steels under different exposure conditions using gel electrolytes N2 - The corrosion behavior of galvanized steels and zinc components under atmospheric exposure depends mostly on the corrosion product‐based cover layer formation under the prevailing conditions. The use of agar‐based gel electrolytes makes it possible to use electrochemical methods to obtain a characteristic value from these cover layers that describe their current and future protective capacity. It is shown here that different states of galvanized steel can be distinguished very well under laboratory conditions and that this method is also suitable for use under practical conditions. Based on the characteristic values and assuming future time of wetness, it is very easy to draw up a forecast for the future corrosion rate, which provides plausible values. KW - Materials Chemistry KW - Metals and Alloys KW - Surfaces, Coatings and Films KW - Mechanical Engineering KW - Mechanics of Materials KW - Environmental Chemistry KW - Corrosion KW - Znc PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-599234 DO - https://doi.org/10.1002/maco.202414389 SP - 1 EP - 16 PB - Wiley VHC-Verlag AN - OPUS4-59923 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - RPRT A1 - Lehmann, Jens A1 - Burkert, Andreas A1 - Wagner, Adrian T1 - Innovation und Sicherheit durch Einsatz von Duplexstählen in Straßentunneln - Korrosivität der Atmosphäre in Straßentunneln und Korrosionsbeständigkeit von Standardprüfkörpern aus nichtrostenden Stählen N2 - Nichtrostende Stähle sind in Tunnelbauwerken weitverbreitete Werkstoffe, die für Konstruktionsteile verschiedenster Art häufig verwendet werden. Von einfachen Hilfsbauteilen wie Kabelkanälen bis hin zu komplexen Konstruktionen von Schilderbrücken. Tunnel sind aus Sicht des Korrosionsschutzes sehr speziell und zählen in Mitteleuropa zu den korrosivsten atmosphärischen Umgebungsbedingungen. Grund hierfür ist die Kombination aus hoher Feuchtigkeit, Abgasen der Fahrzeuge (SO2, NOx) und dem winterlichen Streusalzeinsatz (Cl-). Die daraus entstehen-den feuchten Oberflächenfilme sind hochchloridhaltig und weisen durch Reaktionen mit Schwefeldioxid sehr niedrige pH-Werte auf. Durch die in Tunnelbauwerken gleichzeitige fehlende Abwaschung der Oberflächenfilme durch Regenereignisse können sich die Verunreinigungen an vielen Ausstattungsteilen über die Einsatzzeit aufkonzentrieren. Für metallene Bauteile und insbesondere auch für nichtrostende Stähle ist dadurch eine hohe Korrosionsbeanspruchung vorhanden, die bei der Werkstoffauswahl bzw. beim Korrosionsschutz zu berücksichtigen ist. Aufgrund der Gefahr für das Auftreten Spannungsrisskorrosion bei einigen nichtrostenden Stahlsorten in Tunnelatmosphären, sind Regeln für die Werkstoffauswahl in Tunneln aufgestellt worden, die seit vielen Jahrzehnten gültig sind. Diese Regeln waren bis 2015 national in der allgemeinen bauaufsichtlichen Zulassung Z-30.3-6 für nichtrostende Stähle festgehalten und werden seit 2015 im europäische Regelwerk DIN EN 1993 1 4 (Eurocode 3) verbindlich genormt. In den ZTV-ING für den Straßenbau wird in Abschnitt 4 auf diese Regelwerke Bezug genommen. Die Entwicklungen des nichtrostenden Stahlmarktes in den letzten Jahren, insbesondere für den Bausektor, gehen hin zu den Duplexstählen, da diese aufgrund ihres legierungsspezifisch abgesenkten Nickelgehaltes häufig kostengünstiger als die vergleichbaren Austenite sind. Neben vorteilhaften mechanisch-technologischen Eigenschaften, wie zum Beispiel höhere Festigkeiten, weisen sie zudem auch ausgezeichnete Korrosionsbeständigkeiten auf. Hierzu wurden zahlreiche Studien und Forschungsarbeiten durchgeführt, die diese Vorteile bekräftigen konnten. In Tunnelanwendungen sind Duplexstähle bislang wenig untersucht und deren Korrosionsverhalten kann in dieser speziellen Atmosphäre daher nur bedingt eingeschätzt werden. Das Forschungsprojekt soll diese Erkenntnislücke schließen und durch eine breit angelegte Parameterstudie Duplexstähle für Tunnelanwendungen qualifizieren. Dafür wurden die Korrosionsbedingungen in den Tunneln umfassend untersucht, die Korrosivität der Tunnelatmosphäre anhand normativer Regelwerke beschrieben und dem Korrosionszustand der Prüfkörper aus nichtrostenden Stählen gegenübergestellt. KW - Korrosion KW - Tunnel KW - Spannungsrisskorrosion KW - nichtrostender Stahl PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-607222 N1 - BAM Aktenzeichen: VH 7604 SP - 1 EP - 50 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-60722 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ebell, Gino A1 - Burkert, Andreas ED - Rogge, Andreas ED - Meng, Birgit T1 - Innovative Prüfverfahren für die Korrosionsprüfung von Beton- und Spannstählen N2 - Innovative Prüfverfahren sind immer dann gefordert, wenn z.B. neue Materialien in etablierte Bauweisen inte- griert werden und deren Mehrwert quantifiziert werden soll. Ebenso kommt es vor, dass bestehende Materia- lien mit aktuellen Prüfverfahren nicht hinreichend differenziert und beschrieben werden können. In beiden Fällen erarbeitet die BAM für den Bereich Korrosion und Korrosionsschutz geeignete Prüfverfahren. T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM Green Intelligent Building CY - Berlin, Germany DA - 16.10.2024 KW - Korrosionsprüfung KW - Spannstählen KW - Beton KW - Korrosion PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-612972 SN - 978-3-9818564-7-7 SP - 60 EP - 67 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-61297 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ebell, Gino T1 - Mögliche Fehlerquellen in der Praxis N2 - Durch das alkalische Milieu des Porenwassers im Beton ist der Stahl normalerweise dauerhaft vor Korrosion geschützt. Unter ungünstigen Umgebungsbedingungen (Chlorideintrag, Carbonatisierung) kann die passive Deckschicht auf der Stahloberfläche zerstört werden. Der Korrosionsprozess ist initiiert. Die entstehenden Korrosionsprodukte werden zunächst vom Porengefüge des Betons aufgenommen, ohne dass es zu sichtbaren Schäden am Bauwerk führt. Im fortgeschrittenem Stadium der Korrosion können sich dann Risse und Abplatzungen bilden. Um notwendige Sanierungsmaßnahmen sowohl aus sicherheitstechnischen Gründen als auch aus wirtschaftlichen Erwägungen rechtzeitig einzuleiten, sind frühzeitige und weitestgehend zerstörungsfreie Prüfverfahren zur Ermittlung der aktuellen Korrosionswahrscheinlichkeit der Stahlbewehrung von großer Bedeutung. Deshalb finden Methoden und Verfahren zur laufenden bzw. regelmäßigen Korrosionsüberwachung von Stahlbetonbauwerken ständig größere Beachtung, sowohl im Bereich Forschung und Entwicklung als auch in der Praxis. Die elektrochemische Potentialfeldmessung ist ein etabliertes und weit verbreitetes Verfahren zur Beurteilung des Korrosionszustandes der Bewehrung in Stahlbetonbauwerken. Mit Hilfe dieses Verfahrens können Bereiche korrodierender Bewehrung zerstörungsfrei lokalisiert werden. In der Regel kommt diese Methode bei der Detektion von chloridinduzierter Korrosion zum Einsatz. Der Lehrgang vermittelt den Teilnehmenden in kompakter Form einen zusammenfassenden Überblick über die notwendigen Grundlagen zum Verständnis der Messmethode, der Vorbereitung und Durchführung der Messungen, der notwendigen Begleituntersuchungen sowie der Interpretation der gewonnenen Daten. Der erste Tag ist der theoretischen Ausbildung gewidmet, am zweiten Tag folgt dann die praktische Anwendung der Lerninhalte. Am dritten Tag folgt die Abnahme der praktischen und theoretischen Prüfung zur Erlangung des Sachkundenachweises. T2 - Sachkundelehrgang zur Durchführung von Potentialfeldmessungen CY - Berlin, Germany DA - 24.04.2023 KW - Potentialfeldmessung KW - Korrosion PY - 2023 AN - OPUS4-57497 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - THES A1 - Ebell, Gino T1 - Zur Deckschichtbildung an feuerverzinkten Betonstählen in chloridhaltigen Mörteln N2 - In der vorliegenden Dissertation wurde das Korrosionssystem verzinkter Stahl in alkalischen, zementbasierten Feststoffelektrolyten untersucht. Dabei kamen drei Zementarten mit je vier Chloridgehalten zur Anwendung. Neben dem Korrosionssystem lag das Augenmerk ebenso auf einer adäquaten Beschreibung der Elektrolyteigenschaften. Hierzu wurde die Masseänderung, die Änderung des elektrischen Mörtelwiderstandes und des IR-Drop über die Zeit sowie die Porosität und die Porenwasserzusammensetzung, um nur einige Kenngrößen zu nennen, untersucht. Das Hauptaugenmerk ruht jedoch auf der Beschreibung des Korrosionssystems verzinkter Stahl in Mörtel. Dazu wurden die gebildeten Deckschichten und deren Einfluss auf den Korrosionsfortschritt in Abhängigkeit von der Zementart und des Chloridgehaltes sowie die daraus resultierenden elektrochemischen Kennwerte bestimmt. Die aus den Untersuchungen hervorgehenden Ergebnisse ermöglichen es, die Korrosionssysteme in Abhängigkeit vom Chloridgehalt oder von geometrischen Inhomogenitäten, im Phasengrenzbereich Mörtel/verzinkter Stahl zu differenzieren. Dabei konnte unabhängig von den verwendeten Zementen eine Klassifizierung der Korrosionssysteme über den Phasenwinkel 0,1 Hz erfolgen. Klassifiziert wurden durchtrittskontrollierte und diffusionskontrollierte Korrosionssysteme, Mischsysteme, Übergangssysteme und Korrosionssysteme mit Spaltgeometrie. Für diese Korrosionssysteme konnte festgestellt werden, welche Deckschichten maßgebenden Einfluss auf die Ausbildung eines durchtrittskontrollierten Korrosionssystem haben. Dazu gehören das bereits bekannte Simonkolleit und eine Deckschichtvariante, die bisher noch nicht in der Literatur als Deckschicht an verzinktem Betonstahl in Mörtel oder Beton beschrieben wurde. Für die Mischsysteme erfolgte eine Darstellung der anteiligen Bedeckung mit Simonkolleit, um den Übergang zu einem durchtrittskontrollierten Korrosionssystemen zu beschreiben. Neben der Klassifizierung der Korrosionssysteme kann über die Bestimmung des Phasenwinkels bei 0,1 Hz jedem Korrosionssystem nun auch ein spezifischer B-Wert zugewiesen werden. In Kombination mit der für diese Korrosionssysteme angepassten LPR-Messungen zur Bestimmung des Polarisationswiderstandes können Korrosionsraten ohne signifikante Beeinflussung des Korrosionssystems bestimmt werden. KW - Korrosion KW - Feuerverzinken KW - Betonstahl PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-631696 DO - https://doi.org/10.26204/KLUEDO/7427 SP - 1 EP - 166 PB - RPTU CY - Kaiserslautern AN - OPUS4-63169 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Ebell, Gino A1 - Scheerer, S. A1 - Schacht, G. A1 - Fiedler, M. A1 - Marx, S. A1 - Marzahn, G. A1 - Ritter, R. T1 - Die wechselvolle Geschichte der Carolabrücke in Dresden - Teil 2 N2 - Am 11. September 2024 fand in Dresden ein Ereignis statt, welches man in Deutschland nicht erwartet hatte: der Teileinsturz einer Spannbetonbrücke unter Betrieb ohne Vorankündigung. Die Dresdner Carolabrücke war eine Ikone der Ingenieurbaukunst ihrer Zeit. Sie war ein sehr ästhetisches und schlankes Bauwerk. Ihre Konstruktion und Bau wären auch heute noch eine Herausforderung. Die vorhandenen Unterlagen zeugen von einer hohen Entwurfsqualität und einer sehr sorgsamen Bauausführung. Im Beitrag werden die Entstehungsgeschichte, die Konstruktion selbst und der Bau der Brücke vorgestellt. Es wird der Versuch der Rekonstruktion des Einsturzvorgangs unternommen und die Suche nach der Einsturzursache beschrieben. Am Schluss des Beitrags wird auf das aktuelle Überwachungskonzept eingegangen und ein Ausblick auf das mögliche weitere Vorgehen gegeben. KW - Korrosion KW - Spannstahl KW - Spannungsrisskorrosion KW - Wasserstoff PY - 2025 VL - 2025 IS - 6 SP - 744 EP - 751 PB - Eugen G. Leuze Verlag CY - Bad Saulgau AN - OPUS4-63331 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Ebell, Gino A1 - Scheerer, S. A1 - Schacht, G. A1 - Fiedler, M. A1 - Marx, S. A1 - Marzahn, G. A1 - Ritter, R. T1 - Die wechselvolle Geschichte der Carolabrücke in Dresden N2 - Am 11. September 2024 fand in Dresden ein Ereignis statt, welches man in Deutschland nicht erwartet hatte: der Teileinsturz einer Spannbetonbrücke unter Betrieb ohne Vorankündigung. Die Dresdner Carolabrücke war eine Ikone der Ingenieurbaukunst ihrer Zeit. Sie war ein sehr ästhetisches und schlankes Bauwerk. Ihre Konstruktion und Bau wären auch heute noch eine Herausforderung. Die vorhandenen Unterlagen zeugen von einer hohen Entwurfsqualität und einer sehr sorgsamen Bauausführung. Im Beitrag werden die Entstehungsgeschichte, die Konstruktion selbst und der Bau der Brücke vorgestellt. Es wird der Versuch der Rekonstruktion des Einsturzvorgangs unternommen und die Suche nach der Einsturzursache beschrieben. Am Schluss des Beitrags wird auf das aktuelle Überwachungskonzept eingegangen und ein Ausblick auf das mögliche weitere Vorgehen gegeben. KW - Korrosion KW - Spannstahl KW - Spannungsrisskorrosion KW - Wasserstoff PY - 2025 VL - 2025 IS - 5 SP - 569 EP - 578 PB - Eugen G. Leuze Verlag CY - Bad Saulgau AN - OPUS4-63330 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ebell, Gino T1 - DIN 4871 N2 - Normative Anforderungen an ZfP-Prüfpersonal für ZfPBau sind in der DIN 4871 definiert. Die Ausbildung von Prüfpersonal für Potentialfeldmessung soll gemäß Norm zweistufig erfolgen. T2 - Sachkundelehrgang Potentialfeldmessung CY - Aachen, Germany DA - 03.06.2025 KW - Korrosion KW - Potentialfeldmessung PY - 2025 AN - OPUS4-63308 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schwarz, W. A1 - Wilsch, Gerd A1 - Pichelhöfer, A. A1 - Ebell, Gino A1 - Völker, Tobias T1 - Galvanic chloride extraction by an embedded zinc anode: Ion distribution mapped by laser induced breakdown spectroscopy (LIBS) N2 - An important aspect with regard to the service life of zinc based galvanic anodes and the durability of the corrosion protection of steel in concrete is the “galvanic chloride extraction”. Chloride ions move in the electric field generated by the current, flowing between the galvanic anode and the cathodic steel. Migration leads to an accumulation of anions, e.g. chloride ions, at the anode and depletion of chlorides near the steel rebar surface. The ion migration was studied on steel reinforced concrete specimens admixed with 3 wt.% chloride/wt. cement and galvanically protected by a surface applied embedded zinc anode (EZA). The zinc anode was embedded and glued to the concrete surface by a geo-polymer based chloride free binder. The EZA was operated over a period of 1 year and the ion distribution between anode (EZA) and cathode (steel reinforcement) was studied by laser induced breakdown spectroscopy (LIBS) after 5 months, 7 months and 12 months. The results show that chloride ions efficiently migrate in the direction of the zinc-anode and accumulate there. Chloride distribution in the EZA correlates with the distribution of zinc ions generated by the anodic dissolution of the zinc anode in the binder matrix. The microstructure of the binder matrix and its interface to the zinc-anode are studied by REM/EDX – preliminary results will be reported. T2 - Concrete Solutions 2019 CY - Cluj Napoca, Romania DA - 30.09.2019 KW - Galvanic corrosion KW - Corrosion KW - Chloride extraction PY - 2019 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-488189 DO - https://doi.org/10.1051/matecconf/201928903010 VL - 289 SP - 03010, 1 EP - 5 PB - MATEC Web of Conferences AN - OPUS4-48818 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - BOOK A1 - Ebell, Gino T1 - Zur Deckschichtbildung an feuerverzinkten Betonstählen in chloridhaltigen Mörteln N2 - In der vorliegenden Dissertation wurde das Korrosionssystem verzinkter Stahl in alkalischen, zementbasierten Feststoffelektrolyten untersucht. Dabei kamen drei Zementarten mit je vier Chloridgehalten zur Anwendung. Neben dem Korrosionssystem lag das Augenmerk ebenso auf einer adäquaten Beschreibung der Elektrolyteigenschaften. Hierzu wurde die Masseänderung, die Änderung des elektrischen Mörtelwiderstandes und des IR-Drop über die Zeit sowie die Porosität und die Porenwasserzusammensetzung, um nur einige Kenngrößen zu nennen, untersucht. Das Hauptaugenmerk ruht jedoch auf der Beschreibung des Korrosionssystems verzinkter Stahl in Mörtel. Dazu wurden die gebildeten Deckschichten und deren Einfluss auf den Korrosionsfortschritt in Abhängigkeit von der Zementart und des Chloridgehaltes sowie die daraus resultierenden elektrochemischen Kennwerte bestimmt. Die aus den Untersuchungen hervorgehenden Ergebnisse ermöglichen es, die Korrosionssysteme in Abhängigkeit vom Chloridgehalt oder von geometrischen Inhomogenitäten, im Phasengrenzbereich Mörtel/verzinkter Stahl zu differenzieren. Dabei konnte unabhängig von den verwendeten Zementen eine Klassifizierung der Korrosionssysteme über den Phasenwinkel φ(0,1 Hz) erfolgen. Klassifiziert wurden durchtrittskontrollierte und diffusionskontrollierte Korrosionssysteme, Mischsysteme, Übergangssysteme und Korrosionssysteme mit Spaltgeometrie. Für diese Korrosionssysteme konnte festgestellt werden, welche Deckschichten maßgebenden Einfluss auf die Ausbildung eines durchtrittskontrollierten Korrosionssystem haben. Dazu gehören das bereits bekannte Simonkolleit und eine Deckschichtvariante, die bisher noch nicht in der Literatur als Deckschicht an verzinktem Betonstahl in Mörtel oder Beton beschrieben wurde. Für die Mischsysteme erfolgte eine Darstellung der anteiligen Bedeckung mit Simonkolleit, um den Übergang zu einem durchtrittskontrollierten Korrosionssystemen zu beschreiben. Neben der Klassifizierung der Korrosionssysteme kann über die Bestimmung des Phasenwinkels bei 0,1 Hz jedem Korrosionssystem nun auch ein spezifischer B-Wert zugewiesen werden. In Kombination mit der für diese Korrosionssysteme angepassten LPR-Messungen zur Bestimmung des Polarisationswiderstandes können Korrosionsraten ohne signifikante Beeinflussung des Korrosionssystems bestimmt werden. KW - Korrosion KW - Feuerverzinkter Stahl PY - 2025 UR - https://www.dinmedia.de/de/publikation/dafstb-heft-658/390035991 SN - 978-3-410-65956-3 SN - 0171-7197 IS - 658 SP - 1 EP - 162 PB - DIN Media CY - Berlin AN - OPUS4-63364 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kemmler, Samuel T1 - Large-scale simulations of piping erosion during suction bucket installations N2 - Piping erosion and related fluidization phenomena present major challenges for the installation of offshore suction bucket foundations. We present a fully-resolved, 3D fluid-coupled micromechanical model using the lattice Boltzmann and discrete element methods to simulate suction installation. Validated against benchmark tests and experimental data, the model captures key fluidization behaviors. This presentation goes beyond prior work by showcasing the first large-scale simulations at real bucket dimensions, offering new insights into local soil-fluid interactions during installation and demonstrating the model's scalability and practical relevance. T2 - Gesinus-Treffen 2025 CY - Munich, Germany DA - 12.06.2025 KW - Micromechanical simulation KW - Suction bucket foundation KW - Piping erosion PY - 2025 AN - OPUS4-63381 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Boschmann Käthler, C. A1 - Ebell, Gino A1 - Keßler, S. A1 - Schiegg, Y. A1 - Dauberschmidt, C. A1 - Angst, U. M. T1 - A comparison of methods to assess the resistance of reinforcing steel against chloride‐induced corrosion in concrete - Particular consideration of 12% chromium steel N2 - The critical chloride content Ccrit is an indicator of the corrosion resistance of reinforcing steels in concrete. In this article, several experimental methods for determining the critical chloride content Ccrit of mild and alloyed (12% Cr) steel in cementitious materials are compared. The methods used include accelerated polarization tests and tests employing more natural (unpolarized) conditions in which chloride ingress occurs by diffusion and capillary uptake. The advantages and disadvantages of the methods are discussed, in particular, against the objective of reaching a compromise between applicability to practice and feasibility in laboratory testing. KW - Chloride‐induced corrosion KW - Critical chloride content KW - Reinforced concrete KW - Testing methods PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-628485 DO - https://doi.org/10.1002/maco.202112826 SN - 0947-5117 VL - 73 IS - 3 SP - 306 EP - 325 PB - Wiley-VCH CY - Weinheim AN - OPUS4-62848 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Ebell, Gino A1 - Tannert, S. A1 - Lehmann, Jens A1 - Müller, H. T1 - Offshore Weathering Campaign on a North Sea Wind Farm Part One: Corrosivity Categories N2 - The aim of this study is to investigate the corrosion behavior of materials and coatings in offshore environments, with a focus on determining the corrosivity categories at different locations on wind turbines. The collaboration between the authors enabled a 3‐year weathering campaign at the Hohe See and Albatros offshore wind farms in the North Sea. Metal panels were installed on two wind turbines to assess the corrosivity of different atmospheric conditions. Preliminary results indicate significant variations in corrosivity depending on location and material used, suggesting that current standards may not fully reflect real‐world conditions. The results of the study will help to optimize material selection and corrosion protection strategies for offshore wind farms, potentially extending their lifetime and reducing operating costs. KW - Corrosion KW - Offshore KW - Wind PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-628995 DO - https://doi.org/10.1002/maco.202414711 SN - 1521-4176 SP - 1 EP - 10 PB - Wiley CY - Weinheim AN - OPUS4-62899 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Pirskawetz, Stephan A1 - Ebell, Gino T1 - Überwachung von Spanndrahtbrüchen in Brücken mit Schallemissionsanalyse N2 - Bei einer turnusmäßigen Inspektion der B1 Brücke am Altstädter Bahnhof in Brandenburg an der Havel wurden im Dezember 2019 Risse und Hohlstellen entlang der Längsträger festgestellt. Als Ursache wurde das Versagen eines signifikanten Anteils der Spanndrähte der konzentrierten Spannglieder vermutet. Die Brücke wurde umgehend für den Verkehr gesperrt und nach weiteren, umfassenden Untersuchungen im Mai 2021 abgebrochen. Um die Sicherheit des unter der Brücke geführten Verkehrs zu gewährleisten, wurde die Brücke unter anderem mit einem Schallemissionsmesssystem überwacht. Mit diesem Verfahren ist es möglich, Spanndrahtbrüche zuverlässig zu detektieren und zu lokalisieren. In dem gut einjährigen Überwachungszeitraum wurden mehr als einhundert Spanndrahtbrüche detektiert, die in einigen Bereichen der Brücke besonders konzentriert auftraten. Vor dem Abbruch der Brücke war es möglich, den Nachweis der Detektion von Spanndrahtbrüchen mit der Schallemissionsanalyse und ihre Ortungsgenauigkeit anhand von künstlich erzeugten Drahtbrüchen zu validieren. Weiterhin konnte das sichtbare Schadensbild, Längsrisse und Hohlstellen über den Spannkanälen, auf die lokale Schädigung der Spanndrähte zurückgeführt werden. Derzeit wird ein Merkblatt erarbeitet, in dem die Erfahrungen in der bisherigen Anwendung der Schallemissionsanalyse zum Monitoring von Spanndrahtbrüchen zusammengefasst werden. In diesem Beitrag werden die Grundlagen der Schallemissionsanalyse und die Ergebnisse der Validierungsversuche an der Brücke in Brandenburg dargestellt. Weiterhin werden die Vorteile und Grenzen der Brückenüberwachung mittels Schallemissionsanalyse sowie Maßnahmen zur Sicherstellung der Qualität und der Zuverlässigkeit diskutiert. T2 - fkks infotag - Korrosionsschutz der Infrastruktur als technologische und ökologische Herausforderung CY - Esslingen, Germany DA - 23.01.2025 KW - Spannungsrisskorrosion KW - Schallemission KW - Spannbetonbrücke KW - Spannstahlbruch KW - Faseroptik KW - Wasserstoff KW - zerstörungsfreie Prüfung KW - Spannstahl KW - Ortung KW - Detektion Spannstahlbrüche KW - Spannbeton KW - Brücken KW - Ankündigungsverhalten KW - Schallemissionsanalyse PY - 2025 AN - OPUS4-62751 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ebell, Gino T1 - Untersuchungen und Schadensaufklärung zur Carolabrücke in Dresden N2 - Spannstahlbrücken die in der Vergangenheit mir vergüteten Spannstählen errichtet worden sind können unter ungünstigen Gegebenheiten bei deren Erstellung signifikante Probleme hinsichtlich der Tragfähigkeit bekommen. Im Speziellen kann die wasserstoffinduzierte Spannungsrisskorrosion hier bei der Errichtung der Brückenbauwerke Anrisse an den Spanndrähten erzeugt haben die Jahre später zum Versagen der Brücke führen können. Die Präsentation im Speziellen behandelt den Teileinsturz der Carolabrücke in Dresden. T2 - Workshop Institut Feuerverzinken CY - Altdorf bei Nürnberg, Germany DA - 02.04.2025 KW - Wasserstoff KW - Korrosion KW - Spannungsrisskorrosion PY - 2025 AN - OPUS4-62906 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ebell, Gino T1 - Spannstahlbrücken der Vergangenheit in der Zukunft richtig bewerten N2 - Spannstahlbrücken die in der Vergangenheit mir vergüteten Spannstählen errichtet worden sind können unter ungünstigen Gegebenheiten bei deren Erstellung signifikante Probleme hinsichtlich der Tragfähigkeit bekommen. Im Speziellen kann die wasserstoffinduzierte Spannungsrisskorrosion hier bei der Errichtung der Brückenbauwerke Anrisse an den Spanndrähten erzeugt haben die Jahre später zum Versagen der Brücke führen können. Die Präsentation im Speziellen behandelt den Teileinsturz der Carolabrücke in Dresden. T2 - Dreiländerkorrosionstagung CY - Zurich, Switzerland DA - 31.03.2025 KW - Wasserstoff KW - Korrosion KW - Spannungsrisskorrosion PY - 2025 AN - OPUS4-62905 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Neugum, Tim T1 - Fire tests on HPC columns with and without restraint N2 - Usually, the fire resistance of load-bearing structural elements is determined based on testing of separate members. In this test method, a mechanical load is applied to the member in a force-controlled manner and is held constant throughout the fire test. After applying the mechanical load, the thermal exposure begins according to the ISO 834 fire curve. In this conventional test method, no interaction between the member and the entire building structure is considered. In buildings, the surrounding structure can restrain the thermal expansion of a member in case of fire. This may have both positive and negative effects on the fire resistance of this structural element. T2 - CrossFire – Advanced Structural Fire Engineering at intersections among disciplines CY - Como, Italy DA - 26.05.2025 KW - Substructure method KW - Structural interaction KW - Fire resistance KW - Column KW - Concrete PY - 2025 AN - OPUS4-63351 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Eiz Eddin, Ahmad T1 - Fire induced spalling behaviour of CFRP-reinforced concrete N2 - Fire tests on CFRP-reinforced concrete elements without and with various protection measures to prevent spalling are presented. The protection measures include the application of an intumescent coating to the fire exposed surface as well as the use of a modified concrete mixture containing polypropylene fibres (PP-fibres). T2 - CrossFire School CY - Como, Italy DA - 26.05.2025 KW - Concrete spalling KW - CFRP KW - Polypropylene fibres KW - Intumescent coating PY - 2025 AN - OPUS4-63349 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ebell, Gino T1 - DIN 4871 N2 - Normative Anforderungen an ZfP-Prüfpersonal für ZfPBau sind in der DIN 4871 definiert. Die Ausbildung von Prüfpersonal für Potentialfeldmessung soll gemäß Norm zweistufig erfolgen. T2 - Sachkundelehrgang Potentialfeldmessung CY - Aachen, Germany DA - 25.06.2024 KW - Korrosion KW - Potentialfeldmessung PY - 2024 AN - OPUS4-60585 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ebell, Gino T1 - Corrosivity of Atmospheres and the Resulting Corrosion Protection of Galvanized Steel N2 - The investigation of the corrosivity of atmospheres are major target to ensure the durability of metallic structures. Therefore the corrosivity has to be determined and finally, the right material or corrosion protection system has to be chosen. T2 - Forschungsbeiratssitzung des GAV CY - Darmstadt, Germany DA - 06.06.2024 KW - Corrosion KW - Potentialfeldmessung KW - Atmospheric corrosion PY - 2024 AN - OPUS4-60589 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Mayer, T. F. A1 - Dauberschmidt, C. A1 - Bruns, M. A1 - Eichler, T. A1 - Wiens, U. A1 - Mietz, Jürgen A1 - Gehlen, C. A1 - Ebell, Gino A1 - Gerhard, G. A1 - Osterminski, K. T1 - Das Instandsetzungsprinzip W-Cl N2 - Während das Instandsetzungsprinzip W bei carbonatisierungsinduzierter Korrosion seit vielen Jahren als Standardverfahren etabliert ist, wird seine Anwendbarkeit bei chloridinduzierter Korrosion (W-Cl) in der Fachwelt bis heute kontrovers diskutiert. Zwar ergeben sich aus seiner Anwendung gegenüber anderen Instandsetzungsverfahren auf den ersten Blick u. U. deutliche wirtschaftliche Vorteile, allerdings besteht bei diesem Verfahren ein deutlich höheres Risiko, dass das Instandsetzungsziel nicht erreicht wird. Im vorliegenden Beitrag werden die technischen Grundlagen des Instandsetzungsprinzips W-Cl sowie der aktuelle Kenntnisstand - sowohl für den gerissenen als auch für den ungerissenen Beton - dargestellt und baurechtliche Konsequenzen, die sich aus dem erhöhten Ausführungsrisiko ergeben, diskutiert. Korrosionsmonitoring als Element zum Nachweis des Instandsetzungserfolgs bei Anwendung des Prinzips W-Cl wird vorgestellt. Anhand von Anwendungsbeispielen werden sowohl die Risiken, die mit dem Verfahren verbunden sind, als auch das Potenzial bei erfolgreicher Anwendung veranschaulicht. KW - Korrosion KW - Instandsetzung KW - W-Cl KW - Risse PY - 2020 DO - https://doi.org/10.1002/bate.201900083 SN - 0932-8351 VL - 97 IS - 1 SP - 2 EP - 10 PB - Ernst & Sohn CY - Berlin AN - OPUS4-50246 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Ebell, Gino A1 - Achenbach, R. A1 - Angst, U. A1 - Brem, M. A1 - Dauberschmidt, C. A1 - Eichler, T. A1 - Hariri, K. A1 - Harnisch, J. A1 - Keßler, S. A1 - Mayer, T.F. A1 - Mietz, Jürgen A1 - Pruckner, F. T1 - Elektrochmische Potentialmessung zur Detektion von Bewehrungsstahlkorrosion N2 - Die Potentialmessung kann zum Auffinden korrosionsaktiver Bereiche neben Stahlbetonbauwerken auch bei Spannbetonbauwerken angewandt werden, die mit Spannstählen im direkten Verbund hergestellt werden. Bei Vorspannsystemen mit metallischen Hüllrohren im nachträglichen Verbund ist eine Aussage über den Korrosionszustand des Hüllrohrs, nicht aber des Spannstahls möglich. Messungen an Spannbetonbauteilen erfordern grundsätzlich die besonderen Kenntnisse eines Spezialisten. KW - Korrosion KW - Potentialfeldmessung KW - Corrosion KW - Concrete PY - 2021 SN - 978-3-947971-16-9 VL - Merkblatt B 03 SP - 1 EP - 22 PB - Deutsche Gesellschaft für Zerstörungsfreie Prüfung (DGZfP) CY - Berlin AN - OPUS4-53091 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Valet, Svenja A1 - Bohlmann, Tatjana A1 - Burkert, Andreas A1 - Ebell, Gino T1 - Zinc acetate containing gel pads for electrochemical measurements of Zn samples N2 - Agar gel pads have been used for electrochemical measurements for some time. For zinc in particular, a standard method for measuring the stability of the corrosion product layer is being established. The main interpretation factor is the corrosion product layer resistance RL, as it is easy to determine and interpret. A high corrosion product layer resistance indicates a high level of protection. However, it is not yet known how low the corrosion product layer resistance is for freshly produced zinc samples. As zinc is highly active, it reacts immediately with the environment to form a corrosion product layer, which affects the corrosion product layer resistance. The addition of zinc acetate to the agar gel pads prevents the formation of a surface layer and destroys existing ones. This makes it possible to measure an almost corrosion product-free zinc surface. This is important in defining the range of corrosion product layer resistance for a protective surface. KW - Electrochemistry KW - General Chemical Engineering KW - Analytical Chemistry KW - Corrosion KW - Zinc KW - Korrosion PY - 2023 DO - https://doi.org/10.1016/j.jelechem.2023.117814 SN - 1572-6657 VL - 948 SP - 1 EP - 8 PB - Elsevier B.V. AN - OPUS4-59079 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ebell, Gino A1 - Burkert, Andreas T1 - Neue Erkenntnisse zu wasserstoffinduzierten Spannungsrissen infolge korrosiver Belastung hochempfindlicher Spannstähle in Spannblockverfahren nach TGL 173-33 N2 - Brückenbauwerke, die im Spannblockverfahren hergestellt wurden, können bauartbedingt wasserstoffinduzierte Spannungsrisse über den gesamten Querschnitt eines Spannkanals aufweisen. Das Risswachstum kann infolge dynamischer Beanspruchung über die Nutzungsdauer fortschreiten und zu Spanndrahtbrüchen führen. T2 - 5. Brückenkolloquium CY - Ostfildern, Germany DA - 06.09.2022 KW - Korrosion KW - Spannungsrisskorrosion KW - Spannstahl PY - 2022 SP - 567 EP - 572 PB - Expert -TAE CY - Esslingen AN - OPUS4-55662 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ebell, Gino T1 - Brückenbauwerke aus Spannbeton - der Weg von der initiierung Wasserstoffinduzierter Spannungsrisskorrosion bis zum Bauwerksversagen N2 - Bei der Brücke Altstädter Bahnhof handelte es sich um eine große Spannbetonkonstruktion, die einen elementaren Ver­kehrsknotenpunkt in der Stadt Brandenburg an der Havel bil­dete. Entgegen üblichen Spannbetonkonstruktionen mit kleinen Bündelspanngliedern kamen beim Haupttragwerk in Längsrich­tung großformatige Spannblockspannglieder zum Einsatz. Im Fall der vorliegenden Brücke setzte sich das Spannglied aus 392 ovalen Einzeldrähten aus Hennigsdorfer Produktion zusam­men, welche als spannungsrisskorrosionsgefährdet gelten. Bei Bauwerkserkundungen wurde ein hoher Versprödungsgrad der Spannstähle festgestellt, sodass die Brücke am 19.05.2021 ge­sprengt werden musste. Zuvor traten im Bereich detektierter Spanndrahtbrüche von außen erkennbare Längsrisse in den Stegen anstatt von üblicherweise quer gerichteten Biegerissen an der gezogenen Randfaser auf. Die abweichende Schadens­äußerung im Falle einer Spannstahlschädigung brachte das Bundesministerium für Digitales und Verkehr (BMDV) dazu, weitergehende Untersuchungen durchzuführen. In Zusammen­arbeit mit dem Landesbetrieb Straßenwesen Brandenburg, der Hochschule für Technik und Wirtschaft Dresden sowie der Bundesanstalt für Materialforschung und ­prüfung (BAM) wur­den experimentelle Untersuchungen in­situ konzipiert und durchgeführt. Im Konkreten wurde an zwei Messstellen eine gezielte Schädigung des großformatigen Spannglieds vorge­nommen, um das zuvor vorgefundene Schadensbild nach­zuvoll ziehen und validieren zu können. Konzept, Ergebnisse aus den Untersuchungen und Erkenntnisse für gleichartig ausge­führte Bauwerke sind Gegenstand des ersten Beitrags (Teil 1). Der zweite Teil [1] wird sich im Schwerpunkt den verwendeten Messverfahren und Monitoringsystemen widmen, welche die Durchführung des Versuchs begleiteten. T2 - FKKS-Jahrestagung CY - Berlin, Germany DA - 06.07.2023 KW - Korrosion KW - Spannungsrisskorrosion KW - Spannstahl KW - Wasserstoff PY - 2023 AN - OPUS4-57885 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ebell, Gino T1 - Potential mapping at concrete structures N2 - Potentialmapping is an electrochemical measurement for the detection of active corroding reinforcement at concrete structures. T2 - NDT&E Workshop 2023 CY - Berlin, Germany DA - 23.06.2023 KW - Corrosion KW - Potentialfeldmessung PY - 2023 AN - OPUS4-57884 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ebell, Gino T1 - DIN 4871 N2 - Normative Anforderungen an ZfP-Prüfpersonal für ZfPBau sind in der DIN 4871 definiert. Die Ausbildung von Prüfpersonal für Potentialfeldmessung soll gemäß Norm zweistufig erfolgen. T2 - Sachkundelehrgang zur Durchführung von Potentialfeldmessungen CY - Berlin, Germany DA - 24.04.2023 KW - Potentialfeldmessung KW - Korrosion PY - 2023 AN - OPUS4-57498 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Zekhnini, Khalid T1 - Corrosion behavior of simulated monopile foundation by S355J2 steel in artificial seawater and sediment N2 - The development of offshore wind turbines (WTGs) presents many challenges in terms of safe operation over extended periods of time. One of these is the corrosive environment towards metallic materials, which can lead to a loss of material thickness and thus to a deterioration of mechanical performances, especially the strength of infrastructures. This can be counteracted by painting and cathodic protection (CP). Much research has already been done in this area about inhibiting the corrosion process. However, gaps exist regarding free corrosion. This plays a greater role especially for time intervals during the installation of the systems and their maintenance, during which often no CP can be operated. This is especially true for areas where painting surfaces is impossible e.g., sediment areas. This problem is exacerbated by the different corrosion rates caused by the different zones (water and sediment), with their different amounts of dissolved oxygen. This presentation deals with experiments in artificial seawater and sediment. Classical S355J2 steel samples in the form of coupons were fitted with welding wires that carried out the electrical contact to the outer side of the basin. Inside the basins, the specimens are stored in different zones like water and sediment which should simulate the foundation situation of monopiles. The mass loss was determined gravimetrically, elemental currents between specimens in water and sediment were measured and electrochemical investigations were carried out. The influences of the zones, based on different solved oxygen contents, and the rolling skin towards the corrosion behavior of the mild steel samples were determined in this work. Especially the influence of the sediment showed unexpected behavior, determined by electrochemical investigations. These results allow better conclusions to be drawn about the corrosion behavior of low alloy steels in offshore environments used in sediment and seawater, which cannot always be protected. T2 - Eurocorr 2023 CY - Brussels, Belgium DA - 28.08.2023 KW - Marine Corrosion KW - Offshore KW - Monopile KW - Sediment KW - Artificial seawater PY - 2023 AN - OPUS4-58175 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ebell, Gino A1 - Gündel, M. A1 - Schmid, M. T1 - Anwendung der Feuerverzinkung zum Korrosionsschutz im Stahlwasserbau N2 - Feuerverzinken bietet im Bereich des Wasserbaus potenzial die Nutzungsdauer von Stahlwerkstoffen signifikant zu verbessern. Hierzu gibt es jedoch keine Prüfprozedur die eine Zulassung gem. BAW für die Nutzung im Verwaltungsbereich der WSV zuzulassen. T2 - Forschungsbeiratssitzung der Forschungsvereinigung Feuerverzinken CY - Düsseldorf, Germany DA - 17.06.2025 KW - Korrosion KW - Feuerverzinkter Stahl KW - Wasserbau PY - 2025 AN - OPUS4-63415 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Meinel, Dietmar T1 - Classic Materials Testing in the Light of CT N2 - Currently, mandatory requirements and recommendations for the detection of irregularities in laser beam welded joints are based on classic micrographs as set out in the standard ISO 13919-1:2019. Compared to classic micrographs, computed tomography enables a non-destructive, three-dimensional and material-independent mode of operation, which delivers much more profound results. Even in building material testing, methods with limited informative value can be checked and supplemented by CT examinations. T2 - 13th International Conference on Industrial Computed Tomography (iCT2024) CY - Wels, Austria DA - 06.02.2024 KW - Computed Tomography KW - Additive Manufacturing KW - Machine-Learning Segmentation KW - Air Void System PY - 2024 AN - OPUS4-59568 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Ebell, Gino A1 - Mayer, T. F. T1 - Korrosions- und Verbundverhalten bei beschichteten Fugenblechen N2 - Wechselwirkung von feuerverzinkten Fugenblechen und Beton bei Einsatz in WU-Bauwerken. Mögliche Wasserstoffentwicklung an feuerverzinkten Fugenblechen durch Einwirkung hochalkalischer Medien wie Beton kann durch ausreichend großflächigen, kathodisch wirksamen, Betonstahl unterbunden werden. KW - Korrosion KW - Feuerverzinkter Stahl KW - Korrosionsschutz PY - 2023 SP - 1 EP - 6 CY - online DBV AN - OPUS4-57488 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ebell, Gino A1 - Lehmann, Jens T1 - Erörterung des Messprotokolls N2 - Durch das alkalische Milieu des Porenwassers im Beton ist der Stahl normalerweise dauerhaft vor Korrosion geschützt. Unter ungünstigen Umgebungsbedingungen (Chlorideintrag, Carbonatisierung) kann die passive Deckschicht auf der Stahloberfläche zerstört werden. Der Korrosionsprozess ist initiiert. Die entstehenden Korrosionsprodukte werden zunächst vom Porengefüge des Betons aufgenommen, ohne dass es zu sichtbaren Schäden am Bauwerk führt. Im fortgeschrittenem Stadium der Korrosion können sich dann Risse und Abplatzungen bilden. Um notwendige Sanierungsmaßnahmen sowohl aus sicherheitstechnischen Gründen als auch aus wirtschaftlichen Erwägungen rechtzeitig einzuleiten, sind frühzeitige und weitestgehend zerstörungsfreie Prüfverfahren zur Ermittlung der aktuellen Korrosionswahrscheinlichkeit der Stahlbewehrung von großer Bedeutung. Deshalb finden Methoden und Verfahren zur laufenden bzw. regelmäßigen Korrosionsüberwachung von Stahlbetonbauwerken ständig größere Beachtung, sowohl im Bereich Forschung und Entwicklung als auch in der Praxis. Die elektrochemische Potentialfeldmessung ist ein etabliertes und weit verbreitetes Verfahren zur Beurteilung des Korrosionszustandes der Bewehrung in Stahlbetonbauwerken. Mit Hilfe dieses Verfahrens können Bereiche korrodierender Bewehrung zerstörungsfrei lokalisiert werden. In der Regel kommt diese Methode bei der Detektion von chloridinduzierter Korrosion zum Einsatz. Der Lehrgang vermittelt den Teilnehmenden in kompakter Form einen zusammenfassenden Überblick über die notwendigen Grundlagen zum Verständnis der Messmethode, der Vorbereitung und Durchführung der Messungen, der notwendigen Begleituntersuchungen sowie der Interpretation der gewonnenen Daten. Der erste Tag ist der theoretischen Ausbildung gewidmet, am zweiten Tag folgt dann die praktische Anwendung der Lerninhalte. Am dritten Tag folgt die Abnahme der praktischen und theoretischen Prüfung zur Erlangung des Sachkundenachweises. T2 - Sachkundelehrgang zur Durchführung von Potentialfeldmessungen CY - Berlin, Germany DA - 24.04.2023 KW - Potentialfeldmessung KW - Korrosion PY - 2023 AN - OPUS4-57496 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ebell, Gino T1 - Zur Deckschichtbildung an feuerverzinkten Betonstählen in chloridhaltigen Mörteln N2 - Die Deckschichtbildung an feuerverzinkten Betonstählen in chloridhaltigen Mörteln oder Betonen unterscheidet sich hinsichtlich der Korrosionseigenschaften signifikant von chloridfreien Systemen. Diese Unterschiede wurden in der dargestellten Arbeit dezidiert untersucht und dargestellt, als auch die Wechselwirkung mit dem Mörtel bei direkter Chloridzugabe. T2 - GAV-Forschungbeiratssitzung CY - Aachen, Germany DA - 02.12.2024 KW - Corrosion KW - Galvanized steel KW - Korrosion PY - 2024 AN - OPUS4-62009 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Ebell, Gino A1 - Achenbach, R. A1 - Angst, U. A1 - Dauberschmidt, C. A1 - Eichler, T. A1 - Hariri, K. A1 - Harnisch, J. A1 - Keßler, S. A1 - Kosalla, M. A1 - Mayer, T.F. A1 - Mietz, Jürgen A1 - Pruckner, F. A1 - Sodeikat, C. T1 - Specification B 12 - Corrosion monitoring in reinforced and prestressed concrete structures N2 - This specification describes how corrosion monitoring is used to check the condition of reinforced and prestressed concrete members. In this specification, the term "corrosion monitoring" covers all methods in which it is possible to continuously track corrosion-relevant variables in the area of stationary, built-in sensors. This specification does not cover other possible methods, such as potential field measurements, involving the use of mobile, portable sensors that are placed temporarily on the membersurface to take measurements. KW - Korrosion KW - Corrosion KW - Monitoring PY - 2021 SN - 978-3-947971-14-5 SP - 1 EP - 55 PB - DGZfP CY - Berlin AN - OPUS4-53092 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Haacke, Nasrin T1 - Forschungsvorhaben RUNOFF N2 - Auf dem 20. Deutschen Klempnertag wurde das Forschungsvorhaben RUNOFF unter dem Motto "Die Rolle des Klempners/der Klempnerin als Klimaschützer*in" genauer vorgestellt. Der Fokus lag hierbei auf die Materialeigenschaften Umweltfreundlichkeit und Nachhaltigkeit von Zink und Kupfer. T2 - 20. Deutscher Klempnertag CY - Ulm, Germany DA - 24.01.2024 KW - Runoff KW - Dauerhaftigkeit KW - Zink KW - Kupfer PY - 2024 AN - OPUS4-59525 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Stelzner, Ludwig T1 - Oberflächentextur und ihre Bedeutung für die Drainageleistung N2 - Der Vortrag stellt Einflussfaktoren auf die Drainageleistung von Fahrbahnoberflächentexturen in Kombination mit deren messtechnischer Ansprache vor. T2 - Forschungskolloquium Betonstraßenbau CY - Stuttgart, Germany DA - 06.02.2025 KW - Betonfahrbahn KW - Drainage KW - Oberflächentexturen KW - Dreidimensionale Erfassung PY - 2025 AN - OPUS4-63396 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ebell, Gino T1 - Formation of Corrosion Product Layers on Galvanized Reinforcement in Chloride Containing Mortar N2 - To study a corrosion system such as galvanized steel in chloride containing mortars, more than just some electrochemical studies are required. The addition of chlorides by direct addition to the water will have an influence on the hardening process and consequently on the pore structure, and the investigation of these influences is necessary. Furthermore, a new approach has been investigated which is able to determine the corrosion rate in less than 30 seconds without influencing the corrosion system by intense polarization. T2 - Eurocorr 2024 CY - Paris, France DA - 01.09.2024 KW - Corrosion KW - Galvanized Steel KW - Verzinkt KW - Feuerverzinkt KW - Betonstahl KW - Korrosion PY - 2024 AN - OPUS4-60968 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ebell, Gino A1 - Burkert, Andreas T1 - Standortabhängige Dauerhaftigkeitsbetrachtungen von Zink unter atmosphärischer Korrosion N2 - In maritimer Exposition können Zinkbauteile Nutzungsdauern von 50 Jahren erreichen. Dabei werden Expositionen mit Spritzwasserbelastung durch Meerwasser nicht betrachtet. Normative Betrachtungen und Korrosionsprognosen basierend auf Einjahreswerten liefern hier grundlegend falsche Ergbnisse, da sie eine signifikant höhere Belastung der Atmosphäre mit SO2 voraussetzen. T2 - Korrosionsschutz in der maritimen Technik CY - Hamburg, Germany DA - 04.05.2023 KW - Korrosion KW - Feuerverzinkter Stahl PY - 2023 AN - OPUS4-57489 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Robens-Radermacher, Annika T1 - Temperature dependent modelling approach for early age behavior of printable mortars N2 - For extrusion-based 3D concrete printing, the early age mechanical behavior is influenced by various time dependent phenomena: structural build-up, plasticity as well as viscosity. The structural build-up is governing the stability and early-age strength development of the fresh printable cementitious materials and with that influencing the printability, buildability, and open time of the printing process. Generally, it is influenced by a number of factors, i.e. composition of the printable material, printing regime, and ambient conditions (temperature, humidity, etc.). There are several approaches to model the structural build-up of cementitious materials. All models are based on a time-dependent internal structural parameter describing the flocculation state, which is assumed to be zero after mixing and increases with time. The approaches differ in the definition of the time dependency (linear, exponential, bi-linear). Usually, the parameters are defined for a specific material composition without considering the influence of ambient conditions. In this contribution, the bi-linear structural build-up model [Kruger et al., Construction and Building Materials 224, 2019] is extended by the temperature influence. Temperature changes will occur in real life printing processes due to changing ambient conditions (summer, winter, day, night) as well as the printing process (pressure changes etc.) and have a significant impact on the structural build-up process: an increase of the temperature leads to a faster dissolution of cement phases, accelerates hydration and boosts the Brownian motion. For that reason, the model parameters are simulated as temperature dependent using an Arrhenius function. Furthermore, the proposed extended model is calibrated based on measurement data using Bayesian inference. A very good agreement of the predicted model data with the measured control data was reached. Additionally, the structural build-up model is integrated into a viscoelastic and elastoplastic mechanical model, simulating the whole mechanical behavior during layer deposition. T2 - Eighth International Symposium on Life-Cycle Civil Engineering (IALCCE 2023) CY - Milan, Italy DA - 03.07.2023 KW - 3D concrete printing KW - Material characterization KW - Structural build-up KW - Thixotropy KW - Model calibration PY - 2023 AN - OPUS4-58218 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bühler, M. M. A1 - Hollenbach, P. A1 - Michalski, A. A1 - Meyer, S. A1 - Birle, E. A1 - Off, R. A1 - Lang, Ch. A1 - Schmidt, Wolfram A1 - Cudmani, R. A1 - Fritz, O. A1 - Baltes, G. A1 - Kortmann, G. T1 - The Industrialisation of Sustainable Construction: A Transdisciplinary Approach to the Large-Scale Introduction of Compacted Mineral Mixtures (CMMs) into Building Construction N2 - Abstract: Increasing demand for sustainable, resilient, and low-carbon construction materials has highlighted the potential of Compacted Mineral Mixtures (CMMs), which are formulated from various soil types (sand, silt, clay) and recycled mineral waste. This paper presents a comprehensive inter- and transdisciplinary research concept that aims to industrialise and scale up the adoption of CMM-based construction materials and methods, thereby accelerating the construction industry’s systemic transition towards carbon neutrality. By drawing upon the latest advances in soil mechanics, rheology, and automation, we propose the development of a robust material properties database to inform the design and application of CMM-based materials, taking into account their complex, time-dependent behaviour. Advanced soil mechanical tests would be utilised to ensure optimal performance under various loading and ageing conditions. This research has also recognised the importance of context-specific strategies for CMM adoption. We have explored the implications and limitations of implementing the proposed framework in developing countries, particularly where resources may be constrained. We aim to shed light on socio-economic and regulatory aspects that could influence the adoption of these sustainable construction methods. The proposed concept explores how the automated production of CMM-based wall elements can become a fast, competitive, emission-free, and recyclable alternative to traditional masonry and concrete construction techniques. We advocate for the integration of open-source digital platform technologies to enhance data accessibility, processing, and knowledge acquisition; to boost confidence in CMM-based technologies; and to catalyse their widespread adoption. We believe that the transformative potential of this research necessitates a blend of basic and applied investigation using a comprehensive, holistic, and transfer-oriented methodology. Thus, this paper serves to highlight the viability and multiple benefits of CMMs in construction, emphasising their pivotal role in advancing sustainable development and resilience in the built environment. KW - Decarbonisation KW - Circular economy KW - Recycled materials KW - Demolition wastes KW - Low-carbon construction KW - Building with earth KW - Compressed earth KW - Rammed earth KW - Sustainable construction PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-583260 DO - https://doi.org/10.3390/su151310677 VL - 15 IS - 13 SP - 1 EP - 25 PB - MDPI AN - OPUS4-58326 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Ji, Y. A1 - Becker, S. A1 - Lu, Z. A1 - Mezhov, Alexander A1 - von Klitzing, R. A1 - Schmidt, Wolfram A1 - Stephan, D. T1 - Effect of resting time on rheological properties of glass bead suspensions - Depletion and bridging force among particles N2 - The effect of resting time on the rheological properties of cement suspensions is generally explained by early formed structure and overconsumption of polycarboxylate superplasticizers (PCEs). In this paper, we propose that the influence of resting time on the rheological properties is closely related to size variation of non-absorbed PCE. To identify this, glass bead suspensions were prepared with various amounts of PCE and ionic solution, and their rheological properties were evaluated at various times. We found that the yield stress increases with time at higher PCE concentrations and higher ionic strength solutions. Adsorbed PCE during resting tends to bridge the particles rather than disperse them. In addition, it was found that hydrodynamic radius of PCE increased with resting time, and depletion forces resulting from non-absorbed PCE size changes correlate well with the increased yield stress. KW - Depletion force KW - Ionic stregth KW - PCE KW - Rheology KW - Resting time PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-587193 DO - https://doi.org/10.1111/jace.19469 SN - 0002-7820 SN - 1551-2916 VL - 107 IS - 1 SP - 624 EP - 639 PB - Wiley-Blackwell CY - Oxford AN - OPUS4-58719 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Lorenzoni, Renata A1 - Cunningham, Patrick A1 - Fritsch, Tobias A1 - Schmidt, Wolfram A1 - Kruschwitz, Sabine A1 - Bruno, Giovanni T1 - Microstructure analysis of cement‑biochar composites N2 - The use of biochar as a concrete constituent has been proposed to reduce the massive carbon footprint of concrete. Due to the low density and complex porosity of biochar, microstructural analysis of Portland cement-biochar composites is challenging. This causes challenges to the improvement of the micro-scale understanding of biochar composite behavior. This work advances the microstructural understanding of Portland cement composites with 0, 5, and 25 volume percent (vol%) of cement replaced with wood biochar by applying common characterization techniques of mercury intrusion porosimetry (MIP), gas sorption, scanning electron microscopy, and isothermal heat flow calorimetry (HFC) in conjunction with 1H nuclear magnetic resonance (NMR) and micro-X-ray computed tomography (XCT) analysis techniques. The combination of these techniques allows a multi-scale investigation of the effect of biochar on the microstructure of cement paste. NMR and XCT techniques allow the observation and quantification of the pore space. HFC and MIP confirmed that biochar absorbs moisture and reduces the effective water-cement ratio. Gas sorption, MIP, and NMR shows that 5 vol% replacement does not significantly affect the gel and capillary pore structures. Results from XCT (supported by MIP and NMR) show that biochar can reduce the formation of larger pores. Importantly, XCT results suggest that biochar can act as a flaw in the microstructure which could explain reductions in the mechanical properties. Overall, the mechanical properties already analyzed in the literature are consistent with the microstructural changes observed, and these results highlight the need to carefully tailor the volume fraction of biochar to control its effect on the paste microstructure. KW - Cementitious materials KW - Biochar KW - Microstructure KW - Porosity KW - Pore size distribution PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-610900 DO - https://doi.org/10.1617/s11527-024-02452-5 VL - 57 SP - 16 EP - 175 PB - Springer AN - OPUS4-61090 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kruschwitz, Sabine A1 - Munsch, Sarah Mandy A1 - Telong, Melissa A1 - Schmidt, Wolfram A1 - Bintz, Thilo A1 - Fladt, Matthias A1 - Stelzner, Ludwig T1 - The NMR core analyzing TOMograph: A multi-functional tool for non-destructive testing of building materials N2 - NMR is becoming increasingly popular for the investigation of building materials as it is a non-invasive technology that does not require any sample preparation nor causes damage to the material. Depending on the specific application it can offer insights into properties like porosity and spatial saturation degree as well as pore structure. Moreover it enables the determination of moisture transport properties and the (re-)distribution of internal moisture into different reservoirs or chemical phases upon damage and curing. However, as yet most investigations were carried out using devices originally either designed for geophysical applications or the analysis of rather homogeneous small scale (< 10 mL) samples. This paper describes the capabilities of an NMR tomograph, which has been specifically optimized for the investigation of larger, heterogeneous building material samples (diameters of up to 72 mm, length of up to 700 mm) with a high flexibility due to interchangeable coils allowing for a high SNR and short echo times (50 - 80 m s). KW - Fire spalling KW - Moisture transport KW - Concrete KW - Cement hydration KW - Sensitivity KW - Supplementary cementitous materials KW - Frost salt attack PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-573755 DO - https://doi.org/10.1016/j.mrl.2023.03.004 SN - 2097-0048 VL - 3 IS - 3 SP - 207 EP - 219 PB - Elsevier B.V. AN - OPUS4-57375 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schmidt, Wolfram A1 - Kanjee, J. A1 - Motukwa, G. A1 - Olonade, K. A1 - Dodoo, A. T1 - A snapshot review of future‑oriented standards for cement, admixtures, and concrete: How Africa can spearhead the implementation of green urban construction materials N2 - The existing cement and concrete standards are not capable of making full use of the current technology capacity due to strong focus on conventional concrete and thus they are not fit for the current and future challenges of construction industry. The paper highlights shortcomings with regard to the implementation of the existing standards. It can be seen that future-oriented standards are generally required to contribute to a lower-carbon footprint of the industry. These changes are significantly more relevant in sub-Saharan Africa, due to the rapidly increasing urbanisation challenge and the enormous potentials to develop lower-carbon technologies than elsewhere in the world. KW - Future‑oriented standards KW - Green urban construction KW - Cement PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-582563 DO - https://doi.org/10.1557/s43580-023-00563-9 SN - 2731-5894 VL - 4 IS - 8 SP - 557 EP - 565 PB - Springer International Publishing CY - Springer Nature Switzerland, Cham AN - OPUS4-58256 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schmidt, Wolfram A1 - Kamashanju, Kabibi Charles ED - Rogge, Andreas ED - Meng, Birgit T1 - Circular, bio-based, intelligent ecosystems for climate friendly construction materials supplies N2 - Abstract: Concrete is a major contributor to global energy demand and CO2-emissions, necessitating mitigation strategies. Utilising bio-based resources like polysaccharides, pozzolanic ashes from agricultural waste, and bio-based fibres and aggregates can reduce carbon footprints. However, implementation is hindered by stand- ards favouring scarce and traditionally European materials like fly ash and slag. This highlights the need to diversify resource streams to benefit the global South's abundance of bio-based resources and arable land. An inclusive approach recognizing bio-based resources is required through innovation and regional adaptation. T2 - 63. Forschungskolloquium Green Intelligent Building CY - Berlin, Germany DA - 16.10.2024 KW - Intelligent ecosystems KW - CO2-emissions PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-613160 SN - 978-3-9818564-7-7 SP - 102 EP - 113 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-61316 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Asante, Bright A1 - Soria-Castro, M. A1 - Schmidt, Wolfram ED - Rogge, Andreas ED - Meng, Birgit T1 - Influence of aquacultural and agricultural bio-admixtures and binder components on yield stress and strength of cementitious systems N2 - Abstract: This study investigates the influence of bio-admixtures and bio-ashes from agricultural and aquaculture residues on the workability and strength of cement mortars. While bio-admixtures at low concentrations can enhance the strength, they create similar or lower yield stress as the reference. Bio ash, particularly at a 10% replacement level, maintained good strength, but higher replacements led to significant reductions in both strength and workability. These findings highlight the potential of sustainable construction materials but emphasize the need to balance performance specifications. T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM Green Intelligent Building CY - Berlin, Germany DA - 16.10.2024 KW - Agricultural bio-admixture KW - Aquacultural bio-admixture KW - Binder component PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-612955 SN - 978-3-9818564-7-7 SP - 46 EP - 54 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-61295 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Mezhov, Alexander A1 - Schmidt, Wolfram ED - Rogge, Andreas ED - Meng, Birgit T1 - Rheologie von Bindemittelsuspensionen in Gegenwart von Biopolymeren N2 - Zusatzmittel sind unverzichtbarer Bestandteil von modernem Beton. Ihr Einsatz ist nicht nur technisch und wirtschaftlich sinnvoll, sondern auch notwendig, um Beton umweltfreundlicher zu machen. In diesem Zusammenhang gewinnen nachhaltige Biopolymere zunehmend an Bedeutung, sie weisen jedoch eine große Vielfalt an Molekularstrukturen auf, die zu Unverträglichkeiten mit anderen - wie z.B. Fließmitteln - führen können. In dieser Arbeit werden die Auswirkungen des kombinierten Einsatzes verschiedener Zusatzmittel im Hinblick ihres Einflusses auf die Zementhydratation und den Strukturaufbau von Zementpasten untersucht. T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM Green Intelligent Building CY - Berlin, Germany DA - 16.10.2024 KW - Rheologie KW - Bindemittelsuspension KW - Biopolymer PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-613089 SN - 978-3-9818564-7-7 SP - 147 EP - 152 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-61308 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Robens-Radermacher, Annika A1 - Unger, Jörg F. A1 - Mezhov, Alexander A1 - Schmidt, Wolfram ED - Biondini, F. ED - Frangopo, D. M. T1 - Temperature dependent modelling approach for early age behavior of printable mortars N2 - Structural build-up describes the stability and early-age strength development of fresh mortar used in 3D printing. lt is influenced by several factors, i.e. the composition of the print­ able material, the printing regime, and the ambient conditions. The existing modelling approaches for structural build-up usually define the model parameters for a specific material composition with­ out considering the influence of the ambient conditions. The goal of this contribution is to explicitly include the temperature dependency in the modelling approach. Temperature changes have signifi­ cant impact on the structural build-up process: an increase of the temperature leads to a faster dissol­ ution of cement phases and accelerates hydration. The proposed extended model includes temperature dependency using the Arrhenius theory. The new model parameters are successfully calibrated based on Viskomat measurement data using Bayesian inference. Furthermore, a higher impact of the temperature in the re-flocculation as in the structuration stage is observed. T2 - The Eighth International Symposium on Life-Cycle Civil Engineering (IALCCE 2023) CY - Milano, Italien DA - 02.07.2023 KW - 3D concrete printing KW - Material characterization KW - Structural build-up KW - Thixotropy KW - Model calibration PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-582175 SN - 978-1-003-32302-0 DO - https://doi.org/10.1201/9781003323020-146 SN - 978-1-003-32302-0 VL - 1st Edition SP - 1193 EP - 1200 PB - CRC Press AN - OPUS4-58217 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Weltschev, Margit T1 - DGMK-Projekt 780: Entwicklung einer Prüfmethode zur Bewertung der Materialbeständigkeit von Bauteilen in Mitteldestillatanwendungen N2 - Für Bauteile (Komponenten) von Versorgungsanlagen für flüssige Brenn- und Kraftstoffe muss die Beständigkeit der metallenen Werkstoffe und Polymere nachgewiesen werden. Im Anwendungsfall von Heizöl mit 20 % biogenen Anteilen in Form von Rapsölfettsäuremethylester (FAME, Biodiesel) ist es für eine konservative Beurteilung des Korrosionssystems Werkstoff/Medium/Umgebung wichtig, die Alterungseffekte des Mediums einzubeziehen. Entwicklung eines Prüfverfahrens für die Untersuchung der Beständigkeit von metallenen Werkstoffen und Polymeren in Heizöl und Heizöl-FAME-Blends, das für eine Vorauswahl der Werkstoffe und zum Nachweis der Beständigkeit im Hinblick auf die bauaufsichtlichen Zulassungsverfahren geeignet ist. Ein Schwerpunkt wird bei den metallenen Werkstoffen auf der Erprobung von Messmethoden liegen, mit denen sich in kurzer Versuchszeit ein Korrosionsangriff detektieren lässt. Die untersuchten Werkstoffe Aluminium, Stahl 1.0037, 1.4301, Kupfer, Messing (CuZn40Pb) und Zink (ZP0410) sind in B0, B20, B100 und in 6 Jahre altem B100 beständig. Auch in einem Jahr alten B20 und in einem Jahr alten B100 sind die Werkstoffe beständig. Bei Kupfer blieb die Korrosionsrate in der Flüssigphase sowohl in B20 (0 μ m/ a) als auch in B100 (4 μ m/ a) nach einem Jahr unverändert. Für das 6 Jahre alte B100 stieg die Korrosionsrate des Kupfers an (16 μ m/a). Im Gegensatz dazu sank bei Messing die Korrosionsrate in der Flüssigphase mit dem Alter des Brennstoffs, nach einem Jahr für B20 von 4 μ m/ a auf 1 μ m/a und für B100 von 36 μ m/ a auf 6 μ m/ a, im 6 Jahre alten B100 lag die Korrosionsrate des Messings bei 0 μ m/ a. In 8 Jahre altem B10 trat bei Zink in der Flüssigphase Flächenkorrosion auf, es ist in dem Medium demnach nicht beständig. Messing zeigte örtliche Korrosion in der Gasphase, es ist folglich unbeständig und für den Einsatz in stark gealterten B10 nicht geeignet. Aluminium, 1.0037, 1.4301 und Kupfer sind in dem 8 Jahre alten B10 beständig. Die Änderung der Zugfestigkeit und der Reißdehnung von ACM, HNBR und FKM in Heizöl, B20 und gealterten B10 beträgt < 15 %. Diese Werkstoffe sind in Heizöl, B20 und in gealterten B10 unter Berücksichtigung des von der BAM zur Beurteilung der Beständigkeit festgelegten Grenzwertes von 15 % bei 40 °C als beständig zu bewerten. PUR ist bei 40 °C nicht beständig in B20 und in gealtertem B10. Bei 70 °C ist HNBR nicht in B20 beständig aufgrund der Verringerung der Zugfestigkeit (40 %) und der Reißdehnung (50 %). FKM ist bei 70 °C in Heizöl und in B20 beständig. T2 - Sitzung AK Prüfstellen CY - Berlin, Germany DA - 18.09.2019 KW - Heizöl mit 20% Biodiesel (B20) KW - Beständigkeit KW - Metallene Werkstoffe KW - Polymere Werkstoffe KW - Zugeigenschaften KW - Shore-Härte PY - 2019 AN - OPUS4-50188 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Weltschev, Margit T1 - Bewertung der Beständigkeit von metallenen und polymeren Werkstoffen in Mitteldestillatanwendungen mit Zusatz von Biodiesel N2 - Für Bauteile (Komponenten) von Versorgungsanlagen für flüssige Brenn- und Kraftstoffe muss die Beständigkeit der metallenen Werkstoffe und Polymere nachgewiesen werden. Im Anwendungsfall von Heizöl mit 20 % biogenen Anteilen in Form von Rapsölfettsäuremethylester (FAME, Biodiesel) ist es für eine konservative Beurteilung des Korrosionssystems Werkstoff/Medium/Umgebung wichtig, die Alterungseffekte des Mediums einzubeziehen. Entwicklung eines Prüfverfahrens für die Untersuchung der Beständigkeit von metallenen Werkstoffen und Polymeren in Heizöl und Heizöl-Biodiesel-Blends, das für eine Vorauswahl der Werkstoffe und zum Nachweis der Beständigkeit im Hinblick auf die bauaufsichtlichen Zulassungsverfahren geeignet ist. Ein Schwerpunkt wird bei den metallenen Werkstoffen auf der Erprobung von Messmethoden liegen, mit denen sich in kurzer Versuchszeit ein Korrosionsangriff detektieren lässt. T2 - Seminar: Ausgewählte Kapitel der Werkstofftechnik an der Bergischen Universität Wuppertal CY - Wuppertal, Germany DA - 24.01.2020 KW - Heizöl-20% Biodiesel-Blend KW - Beständigkeitsuntersuchungen KW - Metallene Werkstoffe KW - Polymerwerkstoffe PY - 2020 AN - OPUS4-50298 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF ED - Hahn, Oliver ED - Doil, Thorsten T1 - Workshop Kulturguterhaltung - Vom Dampfkessel zu Nanomaterialien N2 - Sehr geehrte Damen und Herren, liebe Leserinnen und Leser, bereits im ersten Band der N.i.Ke. Schriftenreihe des Netzwerks zur interdisziplinären Kulturerhaltung hatte ich angeführt, dass bei der Untersuchung von kulturellen Artefakten naturwissenschaftliche Untersuchungsmethoden zunehmend an Bedeutung gewinnen, sie eigentlich unverzichtbar geworden sind. Ein besonders einprägsames Beispiel dieser fächerübergreifenden Zusammenarbeit zwischen Geisteswissenschaften, Naturwissenschaften und Restaurierungswissenschaften war die Ausstellung Johannes Vermeer. Vom Innehalten, die in diesem Jahr in der Gemäldegalerie Alter Meister in den staatlichen Kunstsammlungen Dresden gezeigt wurde. Eigens für diese Ausstellung wurde das Gemälde Brieflesendes Mädchen am offenen Fenster einer grundlegenden Restaurierung unterzogen. Diese Restaurierung diente jedoch nicht nur der Reparatur des Bildes. Um sich dem ursprünglichen Zustand des Gemäldes zwischen 1657 und 1659 anzunähern, wurden später hinzugefügte Malschichten großflächig abgenommen. Möglich wurde dies durch unterschiedliche, bildgebende materialwissenschaftliche Untersuchungen im Vorfeld, welche die wissenschaftlichen Grundlagen für die Diskussion über den weiteren Umgang mit der Lesenden schufen. Materialanalytische Verfahren wurden und werden ständig weiterentwickelt und optimiert. Sei es, um aus einer Vielzahl von Einzelmessungen ein Gesamtbild zu erstellen, oder die Größe einer Probenentnahme so zu reduzieren, dass von einer „minimal-invasiven“ oder „quasi nicht-invasiven“ Untersuchung ausgegangen werden kann. Nun feiert die Bundesanstalt für Materialforschung und -prüfung, zusammen mit ihren Vorgängerinstitutionen, den königlichen Versuchsanstalten, in diesem Jahr ihren einhundertfünfzigsten Geburtstag. Sie blickt damit auf eine lange Tradition materialwissenschaftlicher Analysen zurück, an deren Beginn beispielsweise die metallographischen Untersuchungen von Adolf Martens stehen. Derartige Untersuchungen bilden auch heute noch einen wesentlichen Bestandteil archäometallurgischer Forschung. Die Historie bzw. die Weiterentwicklung der Methodik lässt sich hier besonders gut nachzeichnen. Jedoch blicken auch Verfahren zur Charakterisierung weiterer Werkstoffe, wie Glas, Keramik, oder organischer Materialien auf eine lange Geschichte zurück. Die in diesem Band der N.i.Ke.-Schriftenreihe präsentierten Beiträge dokumentieren einerseits aktuelle Forschungsarbeiten, die erst in diesem Jahr in entsprechenden Fachjournalen publiziert wurden, andererseits liegen einige der Arbeiten bereits 50 Jahre zurück. Sie bekunden damit nicht nur die materialtechnologische und historische Bandbreite der Projekte, sondern offenbaren die Vielfältigkeit kulturhistorischer oder restauratorischer Fragestellungen, zu deren Beantwortung natur- und materialwissenschaftliche Forschung wesentliche Beiträge liefern können. Ich bedanke mich bei allen Kolleginnen und Kollegen, die zur Erstellung dieser dritten Ausgabe der N.i.Ke. Schriftenreihe des Netzwerks zur interdisziplinären Kulturerhaltung beigetragen haben. Ihre Aufsätze ermöglichen den Blick in die Vielfältigkeit materialwissenschaftlicher Untersuchungen im Bereich Kunst- und Kulturgut. Ich wünsche Ihnen viel Spaß auf dieser kleinen Zeitreise. T2 - Workshop Kulturguterhaltung - Vom Dampfkessel zu Nanomaterialien CY - Berlin, Germany DA - 17.11.2021 KW - Pergamonmuseums KW - Schriftrollen vom Toten Meer KW - Gold mit Synchrotronstrahlung KW - Kandelaber des Ensembles am Charlottenburger Tor KW - Berliner Tuffsteinfassaden KW - Betondickglasfenster des Glockenturms am Eiermannbau KW - Kaiser-Wilhelm-Gedächtniskirche KW - Radiografische Untersuchung PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-543239 UR - https://netzwerke.bam.de/Netzwerke/Navigation/DE/Netzwerke/NIKE/nike.html VL - 3 SP - 1 EP - 155 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-54323 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Lorenzoni, Renata A1 - Mezhov, Alexander A1 - Fritsch, Tobias A1 - Schmidt, Wolfram A1 - Kruschwitz, Sabine T1 - Effect of Biochar on the Microstructure and Mechanical Response of Cement Paste N2 - The use of biochar as a supplementary cementitious material is proposed to reduce the global greenhouse gas emissions. Since biochar is non-reactive, has a low density and complex porosity, its incorporation into cementitious materials results in microstructural changes and consequently affects the mechanical response. This work advances the mechanical response understanding of Portland cement composites with 0, 5, and 25 volume percent (vol%) of cement replaced with biochar by using in-situ computed tomography, correlating with the microstructural changes analyzed by HFC, gas sorption, MIP, gas sorption, and NMR. The results highlight the influence of the mesoscale structure on mechanical responses and relate the lack of loss of mechanical strength at 5 vol% replacement to the compensation of decreasing larger pores with biochar addition. At 25 vol% replacement, the amount of weakened zones in the paste due to biochar overcompensates the positive effect of the reduction in larger pores, resulting in a loss of mechanical properties. Hence, small amounts of biochar can enhance the microstructure, but the reduction of the carbon footprint is limited. T2 - 24th International Conference on Composite Materials (ICCM24) CY - Baltimore, Maryland, USA DA - 04.08.2024 KW - Supplementary cementitious materials KW - Biochar KW - Microstructure KW - In-situ computed tomography KW - Mechanical proprieties. PY - 2024 DO - https://doi.org/10.14359/51742027 VL - 362 SP - 1020 EP - 1032 PB - International Concrete Abstracts Portal AN - OPUS4-62115 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kruschwitz, Sabine A1 - Munsch, Sarah Mandy T1 - Towards Sustainable Cement Compositions: Exploring the Effects of Clinker Substitutes with NMR and Induced Polarization N2 - The reduction of clinker content in cement is a key strategy to lower the CO₂ footprint of the cement industry. In the recently approved composite cements of class CEM II, a significant portion of the clinker (up to 50%) can already be replaced. A promising option in this context is the so-called LC³ (Limestone Calcined Clay Cement), which offers exciting alternatives especially for countries with large clay deposits. To ensure the performance and durability of such binders, understanding hydration processes and the role of the used supplementary cementitious materials (SCMs) is crucial. The authors present findings from two independent studies: a master thesis and a round-robin experiment conducted within a RILEM Technical Committee. Both studies investigate cementitious materials incorporating SCMs using advanced characterization techniques. The master thesis focuses on early hydration processes during the first 100 hours using Nuclear Magnetic Resonance relaxometry (NMR), providing detailed insights into microstructural development, hydrogen bonding, and water mobility. In contrast, the round-robin experiment explores hydration and durability over a longer timeframe of 3 to 91 days using induced polarization (IP) to study bulk conductivity and its changes with age. For all investigated mixtures—including pure Ordinary Portland (CEMI), Portland Limestone Cement (CEM II) including blends with calcined clay and fly ash—heat flow calorimetry serves as a reference method to monitor hydration progress during the early stages. This approach allows a comprehensive understanding of the effects of SCMs on hydration, combining short-term and long-term perspectives while leveraging complementary techniques. Preliminary results demonstrate a significant increase in NMR T₂ relaxation times with the addition of fly ash, accompanied by a strong reduction in the free water component. Concurrently, early IP measurements reveal a steady increase in impedance with sample age, particularly pronounced in mixtures containing calcined clay. These findings underline the potential of NMR and IP to evaluate hydration and durability-related properties in cementitious systems with reduced clinker content. T2 - 85. Jahrestagung der Deutschen Geophysikalischen Gesellschaft CY - Bochum, Germany DA - 24.02.2025 KW - Nuclear magnetic resonance KW - Induced polarization KW - Supplementary cementitious materials PY - 2025 AN - OPUS4-62989 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kruschwitz, Sabine A1 - Völker, Christoph A1 - Munsch, Sarah Mandy A1 - Klewe, Tim A1 - Zia, Ghezal Ahmad Jan A1 - Schumacher, Katrin A1 - Yared, Kaleb A1 - Schmidt, Wolfram T1 - KI und Robotik im Dienst der Nachhaltigkeit: Beschleunigung innovativer Lösungen im Bausektor N2 - Der Vortrag beschäftigt sich mit der Implementierung fortschrittlicher Technologien in neue Wertschöpfungsketten im Bausektor, insbesondere im Bereich Recycling, zirkuläres Produktdesign und Lebenszustandsanalyse. Im Zentrum stehen Industrie- und Grundlagenforschungsprojekte an der Schnittstelle zwischen Wissenschaft und praktischer Anwendung. T2 - DigiCon 2024 CY - Munich, Germany DA - 21.11.2024 KW - KI KW - Materialdesign KW - Recycling KW - Baumaterial PY - 2024 AN - OPUS4-61800 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Pötzsch, Sina T1 - Entwicklung einer Prüfmethode zur Bewertung der Materialbeständigkeit von Bauteilen in Mitteldestillatanwendungen N2 - Für Bauteile (Komponenten) von Versorgungsanlagen für flüssige Brenn- und Kraftstoffe muss die Beständigkeit der metallenen Werkstoffe und Polymere nachgewiesen werden. Im Anwendungsfall von Heizöl mit 20 % biogenen Anteilen in Form von Rapsölfettsäuremethylester (FAME, Biodiesel) ist es für eine konservative Beurteilung des Korrosionssystems Werkstoff/Medium/Umgebung wichtig, die Alterungs­effekte des Mediums einzubeziehen. Entwicklung eines Prüfverfahrens für die Untersuchung der Beständigkeit von metallenen Werkstoffen und Polymeren in Heizöl und Heizöl-FAME-Blends, das für eine Vorauswahl der Werkstoffe und zum Nachweis der Beständigkeit im Hinblick auf die bauaufsichtlichen Zulassungsverfahren geeignet ist. T2 - DGMK-Projekttreffen CY - Hamburg, Germany DA - 24.10.2019 KW - Heizöl KW - Beständigkeitsbewertungen KW - Biodiesel KW - FAME KW - HVO PY - 2019 AN - OPUS4-50272 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Gerards-Wünsche, Paul A1 - Hille, Falk T1 - Zuverlässigkeitsbasierter Technologietransfer am Beispiel Risslumineszenz Von der ZfP im Labor zum KI-basierten SHM-System für die Industrie – Statusbericht N2 - Der Übergang neuer zerstörungsfreien Prüfmethoden (ZfP) aus dem Labor in die industrielle Anwendung stellt erhebliche Herausforderungen dar. Für visuelle ZfP-Techniken, wie die in dieser Studie verwendete Risslumineszenz-Methode, ist die Automatisierung der Fehlererkennung durch KI-gestützte Computer-Vision-Systeme ein logischer nächster Schritt. Findet dies als kontinuierliche Überwachung statt, entwickeln sich solche Systeme zu einer KI-gestützten SHM-Methode. Die Implementierung dieser Technologien in sicherheitskritischen Anwendungen erfordert jedoch einen robusten Nachweis ihrer Zuverlässigkeit, der durch diese Weiterentwicklung an Komplexität gewinnt. Während etablierte Standards für Probability of Detection (POD)-Studien in ZfP-Systemen existieren, fehlen entsprechende Normen für SHM-Systeme, insbesondere solche, die KI einsetzen. Obwohl statistische Methoden für SHM-Systeme verfügbar sind, um Datenabhängigkeiten zu berücksichtigen, ist ein ganzheitlicher POD-Ansatz notwendig, um beeinflussende und variable Störfaktoren umfassend zu adressieren und die Alterung des SHM-Systems zu berücksichtigen. Diese Arbeit demonstriert Fortschritte bei der Entwicklung einer maßgeschneiderten Methodik, die auf die spezifischen Anforderungen zugeschnitten ist, um die Zuverlässigkeit eines KI-gestützten SHM-Systems auf Basis der Risslumineszenz nachzuweisen. Dieser Ansatz integriert die Prinzipien von POD-Studien mit statistischen Methoden für SHM-Systeme, um eine robuste Zuverlässigkeitsbewertung zu gewährleisten. Er verdeutlicht die erheblichen Herausforderungen, die bereits bei der kontinuierlichen Überwachung einer relativ einfachen visuellen Methode wie der Risslumineszenz auftreten. T2 - DGZfP-Jahrestagung 2025 CY - Berlin, Germany DA - 25.05.2025 KW - Risslumineszenz KW - SHM KW - PoD KW - Zuverlässigkeit KW - ZfP PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-636142 SP - 1 EP - 13 PB - NDT.net AN - OPUS4-63614 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rappsilber, Tim A1 - Krüger, Simone A1 - Raspe, Tina ED - Grayson, Stephen T1 - Engineering Safety in EV's: Analysis of occupant safety using a multifunctional real-scale model car N2 - For vehicle occupant safety, it is important to investigate the effects on people of the pollutants and temperatures emitted by electric vehicle traction batteries in the event of a fire. Fire tests on complete vehicles are the most realistic way of investigating the effects on vehicle occupants. However, these types of real fire tests are very complex and only represent one specific fire scenario with the corresponding specific boundary conditions. We would like to present an engineering method that makes it possible to investigate the effects on the occupants' ability to escape in various damage scenarios with different vehicle geometries without wasting expensive resources. T2 - Interflam 2025 CY - London, United Kingdom DA - 30.06.2025 KW - Lithium ion battery KW - Occuoant safety KW - Gas KW - Flames PY - 2025 SP - 422 EP - 425 AN - OPUS4-63617 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rappsilber, Tim T1 - Safety in EV's: Analysis of occupant safety using a multifunctional real-scale model car N2 - For vehicle occupant safety, it is important to investigate the effects on people of the pollutants and temperatures emitted by electric vehicle traction batteries in the event of a fire. Fire tests on complete vehicles are the most realistic way of investigating the effects on vehicle occupants. However, these types of real fire tests are very complex and only represent one specific fire scenario with the corresponding specific boundary conditions. We would like to present an engineering method that makes it possible to investigate the effects on the occupants' ability to escape in various damage scenarios with different vehicle geometries without wasting expensive resources. T2 - Interflam 2025 CY - London, United Kingdom DA - 30.06.2025 KW - Lithium ion battery KW - Thermal Runaway KW - Analysis KW - Gas KW - Occupant safety PY - 2025 AN - OPUS4-63621 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schubert, Thomas A1 - Máca, Petr A1 - Hering, Marcus A1 - Fiedler, Georg A1 - Beckmann, Birgit T1 - Impact Experiments on Reinforced Concrete Specimens - Investigation of Repeatability and Scaling N2 - Nowadays, the impact resistance of concrete structures has become a prominent concern for critical infrastructure operators, particularly amidst escalating geopolitical tensions. Regulators and design engineers know that reinforced concrete structures can only be developed with high efficiency by considering nonlinear structural and highly nonlinear material behavior. Therefore, specific guidelines on impact design provide instructions for design and analysis of structures required to resist impact loading. These instructions are usually based on published results and evaluated data of impact experiments carried out in laboratories. To widen the knowledge and increase the scientific data the Institute of Concrete Structures (IMB) at TUD Dresden University of Technology (TUD) has carried out many impact experiments on reinforced concrete specimens in recent years. A specially designed drop tower is available for this purpose on the premises of the Otto Mohr Laboratory, TUD. In the framework of the past research at TUD some important issues, such as influence of rebar arrangement, structural thickness, scalability of specimen and repeatability, with regard to experimental impact testing were investigated. This article presents the drop tower facility and research results of impact experiments on reinforced concrete slabs. First, the scalability of impact experiments will be discussed in conjunction with already known theoretical scaling parameters provided by researchers in the past, e.g. Rüdiger et al. [1]. Scalability of experimental data is of huge importance since protective structures made of reinforced concrete differ usually in size in comparison to experimental specimens. The second important research focus is on repeatably of impact experiments. Since impact experiments are usually time consuming and expensive, a certain impact scenario is mostly carried out only once. It is intended to show the range of deviation of impact tests on some already carried out experiments on reinforced concrete slabs. A possible standard deviation is estimated for the applied test setup. T2 - 15th International Conference on Shock & Impact Loads on Structures CY - Gothenburg, Sweden DA - 12.06.2025 KW - Reinforced concrete KW - Drop-weight impact KW - Scaling KW - Repeatability KW - Digital image correlation PY - 2025 SP - 80 EP - 91 AN - OPUS4-63627 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Andrés Arcones, Daniel A1 - Weiser, M. A1 - Koutsourelakis, P-S. A1 - Unger, Jörg F. T1 - Quantifying the uncertainty of predictive simulations in digital twins through the identification of model bias N2 - This work presents a novel approach to quantifying uncertainty in digital twin simulations by addressing model bias through embedded parameter distributions. Traditional Bayesian methods often underestimate uncertainty due to assumptions of model correctness. We propose a hierarchical Bayesian framework combined with Polynomial Chaos Expansion to better capture and propagate uncertainty. The methodology is validated on an analytical example and a real-world case involving thermal deformation predictions of the Nibelungen Bridge, demonstrating improved predictive accuracy and reliability. T2 - fib Symposium 2025 CY - Antibes, France DA - 16.06.2025 KW - Digital Twins KW - Model Bias KW - Predictive simulations KW - Quantifying the uncertainty PY - 2025 SP - 2867 EP - 2873 PB - The fib, Fédération international du béton CY - Antibes, France AN - OPUS4-63629 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Shamsuddoha, Md A1 - Hüsken, Götz A1 - Schmidt, Wolfram A1 - Kühne, Hans-Carsten A1 - Baeßler, Matthias T1 - Superplasticizer and Shrinkage Reducing Admixture Dosages for Microfine Cement in Grout Systems N2 - Grouts have numerous applications including crack repair as maintenance in construction industries. Microfine cements are intensively used for high strength mortar and grout products. They are ideal for injection grouting in structural repair. Such grouts should have suitable rheological properties to be injectable, especially those used in repair and rehabilitation. The use of superplasticizers (SP) in these products is thus becoming increasingly crucial to achieve favorable workability and viscosity properties. A difficulty in such grouts is the plastic shrinkage due to finer particles used. It is thus necessary to determine optimum SP and shrinkage reducing admixture (SRA) dosages for a microfine cement based grout. In this study, a saturation dosage was decided from two Polycarboxylate ether (PCE) based SPs in relation to neat cement using slump flow and rheological parameters. A range of grout mixtures was formulated containing micro silica (MS) and fly ash (FA), and tested for suitable rheological and mechanical parameters. Based on the results, a grout mixture with MS and FA was selected to determine optimum SRA content. According to the results, a SP dosage of 3% by weight of neat cement is sufficient to achieve saturation. The grout material including MS and FA can produce comparable properties to neat cement grout. MS is found to improve compressive strength within the range considered, whereas a higher FA content provides favourable rheological properties. Finally, a SRA dosage of 4%, which could reduce the shrinkage by about 43% after 28d days, is determined for the grout system. T2 - 2nd International Conference on Building Materials and Materials Engineering (ICBMM 2018) CY - University of Lisbon, Portugal DA - 26.09.2018 KW - Grout KW - Microfine Cement KW - Superplasticizer KW - Supplementary Cementitious Materials KW - Shrinkage Reducing Admixture PY - 2019 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-478319 DO - https://doi.org/10.1051/matecconf/201927801001 VL - 278 SP - Article Number 01001 PB - EDP Sciences AN - OPUS4-47831 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Barucker-Sturzenbecher, Meike A1 - Schmidt, Wolfram ED - Schmidt, Wolfram T1 - Learning from the future - How children of Mukuru fancy the city of tomorrow N2 - Sustainability means meeting the needs of today without compromising the needs of the next generations. How can we meet the needs of the next generations, if we do not even know what these needs are? If we do not listen to the next generation and learn from them? Do we even meet the needs of today for everyone on earth? T2 - ISEE Africa - Innovation, Science, Engineering, Education CY - Nairobi, Kenya DA - 30.01.2019 KW - Urban planning KW - Concrete KW - Mukuru KW - Africa KW - Sustainability PY - 2019 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-484832 UR - http://isee-africa.com/wp-content/uploads/2019/07/Innovation-Science-Engineering-Education_High-Quality.pdf SN - 978-3-9818564-2-2 SP - 194 EP - 197 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-48483 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schmidt, Wolfram A1 - Rübner, Katrin A1 - Schneider, Joachim A1 - von Werder, Julia A1 - Gluth, Gregor T1 - 63. DAfStb-Forschungskolloquium in der BAM - Themenblock 2: Nachhaltigkeitspotentiale N2 - Die Bauindustrie ist für rd. 40 % des weltweiten Energieverbrauchs und der Kohlenstoffemissionen verantwortlich. Mit der technologischen Entwicklung wird der Energiebedarf in Zukunft sinken, während sich das Problem grauer Emission verschärft. Daher ist ein verantwortungsvoller Umgang mit Ressourcen der Schlüssel zur Erreichung der Pariser Klimaziele. Der Einsatz klimaschonender Baustoffe weist dabei ein erhebliches Nachhaltigkeitspotential auf. Recycling, Rückgewinnung, Ressourcenschonung und Kreislaufwirtschaft können zu unersetzlichen Bestandteilen der Bautechnik werden. Im Folgenden werden einige Möglichkeiten vorgestellt, die bei der Dekarbonisierung der Bautechnik zukünftig hohe Potentiale aufweisen. Diese wurden beim 63. Forschungskolloquium des DAfStb an der BAM vorgestellt und Details können dem Tagungsband (DOI 10.26272/opus4-61338) entnommen werden. T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM Green Intelligent Building CY - Berlin, Germany DA - 16.10.2024 KW - Bindemittel KW - Klimaschonende Baustoffe KW - Dekarbonisierung PY - 2025 SN - 0005-9846 VL - 75 IS - 4 SP - 131 EP - 134 PB - concrete content UG CY - Schermbeck AN - OPUS4-63068 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Zhang, K. A1 - Mezhov, Alexander A1 - Schmidt, Wolfram T1 - Chemical and thixotropic contribution to the structural build-up of cementitious materials N2 - The structural build-up of fresh cement paste is often considered as a purely thixotropic phenomenon in literature even though cementitious materials undergo a non-reversible hydration process that can have an influence on the structuration process. In the current paper a method is proposed to validate the impact of the non-reversible structural build-up. It is shown that fresh cement paste samples lose their structural gain almost completely due to thixotropy while the structural build-up due to hydration can be observed but occurs in a significantly lower order of magnitude over the course of the first hours of hydration. In addition, it is shown, that the chemical component of the structural build-up accelerates with the onset of the acceleration period of hydration, while its contribution in the entire structural build-up remains constant. KW - Thixotropy KW - Structural build-up KW - Penetration test KW - Rheological properties PY - 2022 DO - https://doi.org/10.1016/j.conbuildmat.2022.128307 SN - 0950-0618 VL - 345 IS - 128307 SP - 1 EP - 10 PB - Elsevier Ltd. AN - OPUS4-58248 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Mezhov, Alexander A1 - Schmidt, Wolfram A1 - Zhang, H. A1 - Diesendruck, Ch. E. T1 - The effect of the charge density of a comb polyphosphate superplasticizer on the structural build-up of cement paste N2 - Synopsis: Lately, there has been rising attention to superplasticizers (SP) based on polyphosphate esters. However, the influence of the molecular structure of the polyphosphate polymers on time-dependent properties such as structural build-up has not been examined yet intensively. To investigate this effect, three comb polyphosphate superplasticizers with different charge densities were synthesised by free radical polymerisation. Our findings indicate that SP with the lowest and medium charge densities extend the induction period more strongly than the SP with the highest charge density. The reduction of the structural build-up rate is linearly dependent on the dosage and concentration of the functional group of polyphosphate SP in the cementitious system. This study proposes a mathematical equation expressing the relationship between the structural build-up rate during the induction period and the molecular structure of the polyphosphate SP. T2 - 13th International Conference on Superplasticizers and Other Chemical Admixtures in Concrete CY - Milan, Italien DA - 10.07.2022 KW - Admixture KW - Superplasticizer KW - Polyphosphate KW - Structural build-up PY - 2022 DO - https://doi.org/10.14359/51736079 VL - 354 SP - 255 EP - 262 PB - ACI Special Publications AN - OPUS4-58321 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Baeßler, Matthias T1 - On the Reassessment of Bridge Superstructure Vibrations for High-Speed Traffic N2 - The acceleration thresholds of bridge superstructures remain criti-cal for designing and reassessing railway bridges on high-speed lines, with ballasted track systems historically limited to 3.5 m/s² vertical accelerations due to destabilization risks. As part of the European InBridge4EU project, this study addresses methodological uncertainties in linking vertical bridge vibrations to lateral track creep—a key focus area for modernizing assess-ment protocols. A comparative analysis of two acceleration postprocessing methods (peak identification vs. fatigue-derived rainflow counting) as part of a recently proposed framework was conducted using an example bridge and train combination. Results demonstrate that rainflow counting yields more conservative creep estimates with the bulk of cumulative vibration-induced creep attributable to accelerations exceeding 3 m/s². However, discretizing acceleration ranges into 1 m/s² bins introduced significant errors compared to continuous cycle data, highlighting sensitivity to analysis parameters. These findings underscore the complexity of reconciling laboratory-derived harmonic vibration models with real-world bridge dynamics, where non-uni-form acceleration patterns dominate. The research directly informs ongoing efforts to refine standardized criteria for ballasted track stability, particularly through the InBridge4EU project's systematic re-evaluation of vibration lim-its and their engineering implications. By quantifying discrepancies between computational approaches, this work advances the development of robust protocols for predicting track degradation under high-speed operational loads. T2 - 11th International Conference on Experimental Vibration Analysis for Civil Enginering Structures (EVACES 2025) CY - Porto, Portugal DA - 02.07.2025 KW - Infrastructure KW - Railway bridges KW - Ballasted track KW - Railway bridge dynamics KW - Rainflow counting PY - 2025 AN - OPUS4-63658 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Baeßler, Matthias T1 - Review of Ballasted Track Destabilization on Shake Table Tests N2 - Shake table tests have been used for a long time to understand the densification and fluidization of granular materials. While purely vertical shaking is quite unlikely to be found in vibration analysis when it comes to granular materials as soils, it has been found that the vertical vibration of railway bridge support structures can affect the fabric of the ballasted track on top. Starting from the experience at French railway lines with destabilizing track conditions on short bridges in high speed lines in the 1990s, various shake table test configurations have been used to investigate the destabiliza-tion of ballast at high acceleration levels. This article describes the effects of the variously investigated dynamic excitations of railway bridges on the bal-lasted track itself. T2 - 11th International Conference on Experimental Vibration Analysis for Civil Enginering Structures (EVACES 2025) CY - Porto, Portugal DA - 02.07.2025 KW - Railway bridge dynamics KW - Acceleration limit KW - Ballast destabilization KW - Shake table tests PY - 2025 AN - OPUS4-63659 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Seifert, Lando T1 - Grundlagen Korrosion und Korrosionsschutz N2 - Im Rahmen des Events des jungen Berufsnetzwerks "die junge gfkorr" der Gesellschaft für Korrosionsschutz e.V. beim Industriepartner Dörken Coatings wurde dieser Vortrag über die Grundlagen der Korrosion und des Korrosionsschutzes gehalten. Themen dieses Vortrags waren unter anderen die Bimetallkorrosion, atmosphärische Korrosion und einige Aspekte des Korrosionsschutzes durch Beschichtungen. T2 - die junge gfkorr @ Dörken Coatings CY - Herdecke, Germany DA - 26.05.2025 KW - Korrosion KW - Korrosionsschutz KW - Bimetallkorrosion PY - 2025 AN - OPUS4-63263 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - RPRT A1 - Seifert, Lando A1 - Müller, Thoralf A1 - Ebell, Gino T1 - Schlussbericht zum Forschungsvorhaben: "WIPANO Spannstahlsicherheit" - Entwicklung eines neuen Prüfverfahrens zur Beurteilung der Spannungsrisskorrosionsempfindlichkeit von Spannstählen für den Spannbetonbau N2 - Für die Sicherheit von Spannbetonbauwerken ist eine Empfindlichkeitsprüfung von Spannstahlprodukten gegenüber der wasserstoffinduzierten Spannungsrisskorrosion zwingend erforderlich. Die derzeitig normativ festgelegten Prüfmethoden nach DIN EN ISO 15630-3 zeigen nachweislich Schwächen hinsichtlich der Reproduzierbarkeit der Ergebnisse und erschweren damit die eindeutige Bewertung der Empfindlichkeit. Ziel des Forschungsvorhabens der Förderinitiative WIPANO des BMWK war es, die Prüfmethode hinsichtlich der Reproduzierbarkeit und Aussagesicherheit zu verbessern. Im Projekt wurden durch materialseitige, elektrolytische und verfahrenstechnische Parameteränderungen konstante und reproduzierbare Prüfbedingungen geschaffen. Dies ermöglichte eine eindeutige Differenzierung zwischen Gut- und Schlechtprodukten. Innerhalb des Projekts wurde ein Ringversuch initiiert, welcher die Anwendbarkeit und Reproduzierbarkeit der neuen Prüfmethode bestätigte. Das neue Prüfverfahren wurde hinsichtlich der Anwendbarkeit für das Spannstahlerzeugnis Draht evaluiert. Ein entsprechender Normentwurf mit einem Vorschlag für ein Konformitätskriterium dieser Erzeugnisse wurde dem zuständigen ISO-Gremium präsentiert und zur Abstimmung überlassen. Nach aktueller Rückmeldung seitens des Gremiums wird der Normentwurf den Eingang in den informativen Anhang der Prüfnorm finden, dies könnte den Weg für eine Spiegelung auf europäischer und nationaler Normungsebene ebenen. KW - Spannstahl KW - Prestressing Steels KW - DIN EN ISO 15630-3 KW - Spannungsrisskorrosion KW - Stress corrosion cracking KW - Wasserstoff KW - Hydrogen PY - 2023 SP - 1 EP - 94 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-57402 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schraut, Katharina A1 - Adamczyk, Burkart A1 - Adam, Christian A1 - Stephan, D. A1 - Meng, Birgit A1 - Simon, Sebastian A1 - von Werder, Julia T1 - Synthesis and characterisation of alites from reduced basic oxygen furnace slags N2 - Basic oxygen furnace slags (BOFS) are by-products of the steelmaking process. Several researchers have studied the production of Portland cement clinker and metallic iron from BOFS via a reductive treatment. In this study, we applied a carbothermal reduction of BOFS in a technical-scale electric arc furnace and characterised the clinker-like products. Those clinker-like non-metallic products (NMPs) had a chemical and mineralogical composition comparable to clinker for ordinary Portland cement (OPC) and contained large elongated alite crystals as major component. The pure NMPs reacted more slowly and achieved a lower degree of hydration compared with commercial OPC. If the reactivity of the products can be further increased by employing specific adaptations, it can be used as a full clinker substitute for OPC. Nevertheless, it is also an option to use the material without further modifications as a cement component or concrete addition, which contributes to the strength development in both cases. KW - BOFS KW - Hydration products KW - Thermal analysis KW - X-ray diffraction PY - 2021 DO - https://doi.org/10.1016/j.cemconres.2021.106518 SN - 0008-8846 VL - 147 SP - 6518 PB - Elsevier Ltd. AN - OPUS4-52939 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Nikoonasab, Ali A1 - Müller, Thoralf A1 - Gluth, Gregor T1 - Study of steel behavior in synthetic pore solutions of GGBFS-containing cements using EIS N2 - Steel corrosion in sulfide-containing solutions presents a challenge in a number of environments and appli¬cations, such as the kraft process, the oil and gas industry, and reinforced concrete structures. In concrete, sulfides are introduced by ground granulated blast-furnace slag (GGBFS), which is a widespread component of standard cements and which can also be utilized in the production of alkali-activated materials (AAMs). However, a knowledge gap exists concerning the compositions of pore solutions in GGBFS-containing cements, especially regarding sulfur and its various species and understanding how these sulfur species affect the surface layer and the corrosion behavior of steel in such environments. The present study employed electrochemical impedance spec¬tros-copy to study the behavior of steel in synthetic solutions representing GGBFS-containing cements and AAMs. The electrochemical behavior of steel in sulfide-containing solutions differs from that observed in ordinary Portland cement solutions, generally exhibiting lower open circuit potentials and polarization resistances in the former environments. This suggests that the criteria or standards used to assess the probability of steel corrosion in Portland cement concrete are not applicable to GGBFS-containing concrete due to differences of their pore solution compositions. T2 - International Workshop on Impedance Spectroscopy – IWIS 2024 CY - Chemnitz, Germany DA - 24.09.2024 KW - Cement KW - Ground granulated blast-furnace slag KW - Sulfide KW - Steel corrosion KW - Impedance spectroscopy PY - 2024 DO - https://doi.org/10.1109/IWIS63047.2024.10847235 SP - 44 EP - 48 PB - IEEE AN - OPUS4-61221 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schraut, Katharina A1 - Adamczyk, Burkart A1 - Adam, Christian A1 - Stephan, Dietmar A1 - Meng, Birgit A1 - Simon, Sebastian A1 - von Werder, Julia A1 - Hirsch, Tamino A1 - Manninger, Tanja T1 - Effect of gypsum on the hydration of fused cement clinker from basic oxygen furnace slag N2 - Fused cement clinker can be produced from molten basic oxygen furnace slag (BOFS) by way of a reductive thermochemical treatment. During the thermochemical treatment, oxidic iron is reduced to metallic iron and separated. The resulting low-iron slag has a chemical and mineralogical composition similar to ordinary Portland cement (OPC) clinker. In this study, the hydraulic reactivity of the fused clinker from BOFS with and without gypsum was investigated using isothermal calorimetry, differential scanning calorimetry, in situ X-ray diffraction and powder X-ray diffraction. Furthermore, a synthetic fused clinker without foreign ions and fused clinker produced by a mixture of both materials was studied. The hydraulic reaction of the fused clinker from BOFS was considerably slower than that of OPC. However, the reaction can be accelerated by adding gypsum as a sulfate carrier. Furthermore, the results showed an increased reaction rate with decreasing content of foreign ions such as Fe, P or Mn. KW - General Materials Science KW - Building and Construction PY - 2024 DO - https://doi.org/10.1680/jadcr.23.00070 SN - 0951-7197 SP - 1 EP - 19 PB - Telford AN - OPUS4-59391 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Müller, Thoralf T1 - Statusbericht zum FGS Projekt Gefügeveränderung bei trockener Grobbearbeitung N2 - Der Vortrag gibt eine Übersicht zum Stand des Projekts zum Thema Gefügeveränderung bei trockener Grobbearbeitung. Es wurden vier verschiedene trockene Oberflächenbearbeitungsverfahren an 2 Werkstoffen eingesetzt um Testoberflächen zu schaffen. Die so gefertigten Oberflächen wurden lichtmikroskopisch untersucht und die jeweiligen Rauhigkeitskennwerte bestimmt. Weiterhin wurden metallografische Querschliffe angefertigt um die verfahrens- bzw. materialabhängigen Einflüsse auf mögliche Gefügeveränderungen zu untersuchen. Zusätzlich wurden elektrochemische Polarisationsversuche durchgeführt um die oberflächenspezifische Korrosionsbeständigkeit der nichtrostenden Stahlproben zu quantifizieren. T2 - Jahrestagung der Forschungsgemeinschaft Schleifen (FGS) 2023 CY - Würzburg DA - 21.03.2024 KW - Schleifbearbeitung KW - Korrosion KW - Nichtrostender Stahl KW - Stahl KW - Verformung PY - 2024 AN - OPUS4-59739 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Adam, Christian A1 - Schraut, Katharina A1 - Adamczyk, Burkart A1 - Weimann, Karin A1 - Gluth, Gregor T1 - Erzeugung klimaschonender Bindemittel als Alternativen zu Zement durch thermochemische Behandlung von mineralischen Nebenprodukten und Abfällen N2 - Die Zementindustrie erzeugt etwa 6-7% der globalen CO2-Emissionen und steht damit als Industriezweig vor dem Hintergrund einer anvisierten Klimaneutralität vor gewaltigen Herausforderungen. Der Prozess der Klinkerherstellung wurde über die vergangenen Jahrzehnte bereits kontinuierlich optimiert. Seit 1990 ist es der deutschen Zementindustrie gelungen, die spezifischen CO2-Emissionen der Zementproduktion u. a. durch den Einsatz alternativer, nicht fossiler Brennstoffe und durch Absenkung des Klinkergehalts im Zement um 20 % zu senken. Weitere konventionelle Minderungsstrategien versprechen jedoch nur noch wenig zusätzliche Reduktion. Im Falle des Portlandklinkers besteht die Schwierigkeit darin, dass zwei Drittel der CO2-Emissionen rohstoffbedingt durch die Entsäuerung des Kalksteins (CaCO3) anfallen, die durch die beschriebenen Maßnahmen nicht weiter abgesenkt werden können. Vielmehr wird es erforderlich sein, noch zu entwickelnde oder zu optimierende Technologien anzuwenden und ggf. alle relevanten Ebenen wie Produktion, Weiterverarbeitung und Anwendung von Zement und Beton neu zu denken. Neben technologischen Ansätzen zur CO2-Abscheidung mit nachfolgender langfristiger Speicherung (Carbon Capture and Storage – CCS) oder Verwertung (Carbon Capture and Utilisation – CCU) werden auch alternative Rohstoffe für die Zementproduktion und alternative Bindemittel in Betracht zu ziehen sein. T2 - Berliner Konferenz Mineralische Nebenprodukte und Abfälle CY - Berlin, Germany DA - 25.04.2022 KW - Zement KW - Sekundärrohstoff PY - 2022 SN - 978-3-944310-58-9 SP - 372 EP - 385 PB - TK-Verlag CY - Neuruppin AN - OPUS4-54737 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Nikoonasab, Ali A1 - Müller, Thoralf A1 - Licht, M. A1 - Raupach, M. A1 - Gluth, Gregor ED - Rogge, Andreas ED - Meng, Birgit T1 - Sulfides in the pore solutions of GGBFS-containing concretes - Influence on the corrosion of reinforcing steel N2 - Steel corrosion in sulfide-containing solutions is a challenge in various environments, such as reinforced concrete structures. In concrete, sulfides are introduced by ground granulated blast-furnace slag (GGBFS), used in standard cements and alkali-activated materials (AAMs), affecting steel corrosion. This study examined steel in synthetic GGBFS-containing cement pore solutions using electrochemical techniques. Compared to Portland cement solutions, steel in sulfide-containing solutions exhibits lower open circuit potentials and polarisation resistances. Thus, Portland cement concrete corrosion assessment standards are unsuitable for GGBFScontaining concrete. T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM Green Intelligent Building CY - Berlin, Germany DA - 16.10.2024 KW - Corrosion KW - Reinforcing steel PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-612963 SN - 978-3-9818564-7-7 SP - 55 EP - 59 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-61296 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Müller, Thoralf T1 - Bericht aus den DIN Ausschüssen "Korrosion und Korrosionsschutz" und "Korrosionsprüfverfahren" N2 - Der Vortrag gibt einen Überblick über aktuelle Themen und Normen, die in den DIN Ausschüssen NA 171 "Korrosion und Korrosionsschutz" und NA 177 "Korrosionsprüfverfahren" behandelt werden. Stand des Berichts ist Oktober 2024. T2 - GfKorr Gemeinschaftssitzung der AKs "Korrosionsuntersuchungen und -überwachung" und "Grundlagen und Simulation" CY - Online meeting DA - 13.11.2024 KW - Korrosion KW - Normung KW - DIN KW - Korrosionsschutz KW - Korrosionsprüfung PY - 2024 AN - OPUS4-62306 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Burkert, Andreas T1 - Bedeutung der Wirksumme bei Nichtrostenden Stählen N2 - Anhand der Wirksumme ist eine Abschätzung des legierungsabhängigen Einflusses auf den Korrosionswiderstand gegen chloridhaltige Medien möglich. Die berechneten Werte sind nur bei optimaler Wärmebehandlung und Verarbeitung zutreffend. Die Anwendung einer einfachen Formel unter Berücksichtigung von Chrom, Molybdän und Stickstoff ist in der Regel völlig ausreichend. Das daraus abgeleitete Ranking von Werkstoffen ist für diverse technische Regelwerke und zur Unterstützung der Werkstoffauswahl geeignet. Für die Warenein-/Ausgangskontrolle ist die alleinige Feststellung der Wirksumme unzureichend. Ergänzende Korrosionsuntersuchungen/-prüfungen zur Beschreibung des Korrosionswiderstandes sind dafür notwendig. Gleiches gilt für die Beurteilung von Schadensfällen. Hier sind Verarbeitung, Einsatzbedingungen und die Konstruktion von ausschlaggebender Bedeutung. T2 - Fortbildung Kursleiter Kompetenzzentren Edelstahl Rostfrei CY - Trier, Germany DA - 25.09.2023 KW - Nichtrostender Stahl KW - Korrosion KW - Wirksumme PY - 2023 AN - OPUS4-58453 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Müller, Thoralf T1 - Aktueller Stand Wipano Projekt: Spannstahlsicherheit – Entwicklung eines neuen Prüfverfahrens zur Beurteilung der Spannungsrisskorrosionsempfindlichkeit von Spannstählen im Spannbetonbau N2 - Die Präsentation stellt das Wipano Projekt Spannstahlsicherheit vor. Es werden die Projektidee, die Projektziele sowie der Projektplan vorgestellt. Weiterhin werden die aktuellen Ergebnisse der dort gemachten Untersuchungen dargestellt. T2 - Sitzung des Normausschusses NA 062-01-77 AA CY - Online meeting DA - 28.10.2020 KW - Korrosion KW - Spannstahlprüfung KW - Spannstahl KW - Normung KW - Spannungsrisskorrosion PY - 2020 AN - OPUS4-51482 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Seher, Julia T1 - Leichte Gesteinskörnungen aus Bau- und Abbruchabfällen - Applikation in der Denkmalpflege N2 - Im Rahmen des BMBF-geförderten Forschungsprojekt ReMin - REALight werden in einem Projektteam aus Industriepartnern und Forschungseinrichtungen unter Koordination der Bauhaus-Universität Weimar leichte Gesteinskörnungen aus Bau- und Abbruchabfällen und industriellen Nebenprodukten auf thermischen Weg hergestellt. Die Aufgabe der Bundesanstalt für Materialforschung und -prüfung (BAM) ist es, diese im Drehrohrofen erzeugten Blähgranulate für gebundene Anwendungen in Beton und Mörtel umfassend zu charakterisieren. Gemeinsam mit der Opus Denkmalpflege GmbH wird die Applikation feiner, gebrochener Blähgranulate in leichten Steinergänzungsmörteln für die Restaurierung von Sandsteinobjekten untersucht. Hierzu wird ein zweischichtiges Mörtelsystem bestehend aus Füll- und einem Deckmörtel entwickelt. Erste Ergebnisse der Rezepturentwicklung verschiedener kalkhaltiger Leichtmörtel mit gebrochenen Blähgranulaten werden vorgestellt. Die neuen Leichtmörtel sind hinsichtlich der entwickelten Druckfestigkeit gleichwertig gegenüber herkömmlichen Restauriermörteln. T2 - 21.Internationale Baustofftagung (ibausil) CY - Weimar, Germany DA - 13.09.2023 KW - Leichte Gesteinskörnungen KW - Recycling KW - Denkmalpflege KW - Leichtmörtel PY - 2023 AN - OPUS4-58329 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Seher, Julia A1 - Rübner, Katrin A1 - Müller, Constanze A1 - Martin, F. A1 - Pniok, N. A1 - Dreisow, B. ED - Döring, I. ED - Villagran Zaccardi, Y. ED - Müller, A. T1 - Lightweight aggregates made from construction and demolition waste - Application in lightweight concrete and mortars N2 - Heterogeneous construction and demolition waste can be used as raw material to produce lightweight aggregates (LWA) similar to expanded clays. In the joint research project “REALight”, LWA were produced from masonry rubble in a thermal expanding process using a pilot production plant with a rotary kiln. Our research focuses on the characterisation of the novel LWA and their use in different hydraulically bound applications. Infra-lightweight concrete (ILC) was produced with the novel LWA, which accounts for two thirds of total aggregate volume, and Celitement, which is a hydraulic binder with a low carbon footprint. Its dry bulk density is ≤ 800 kg/m³. Strength and durability properties are comparable to ILC data from the literature. Lime-based repair mortars (LRM) containing LWA are beneficial for sandstone conservation due to their similar properties regarding porosity, water absorption and strength. A two-layer repair mortar system, which consists of a filling mortar to fill large voids and a covering mortar to modulate the surface texture to the historic sandstone, was developed. In our contribution, we present results of the LWA characterisation according to the European standard EN 13055:2016. Requirements and challenges of the use of the novel LWA in ILC and LRM are discussed. T2 - V International Conference Progress of Recycling in the Built Environment CY - Weimar, Germany DA - 10.10.2023 KW - CDW recycling KW - Lightweight aggreagtes KW - Lightweight concrete KW - Masonry rubble KW - Repair mortar PY - 2023 SN - 978-2-35158-238-1 VL - PRO 137 SP - 85 EP - 92 PB - RILEM Publications S.A.R.L. CY - Champs-sur-Marne, Frankreich AN - OPUS4-58991 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schnell, Alexander A1 - Rübner, Katrin A1 - Seher, Julia A1 - Müller, Constanze A1 - Müller, Anette A1 - Liebezeit, Steffen A1 - Fenner, Jacob A1 - Martin, Falk A1 - Pniok, Nicole T1 - Manufacturing and Application of Lightweight Aggregates from Construction and Demolition Waste N2 - The objective of the REALight project is the development of a thermal process to produce lightweight aggregates in pilot scale and the implantation of a method to recover gypsum. Beside construction and demolition waste, various industrial by‐products are studied as raw materials. The raw materials have so far been unused or used in applications with lower quality requirements. To prove the performance of the lightweight aggregates, their technical properties are tested and their use in different applications is studied, e.g., for lightweight mortars as well as lightweight concretes. KW - Construction and demolition waste KW - Flue gas desulfurization gypsum KW - Industrial by-products KW - Infra-lightweight concrete KW - Lightweight aggregates PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-604643 DO - https://doi.org/10.1002/cite.202300211 SN - 0009-286X VL - 96 IS - 7 SP - 969 EP - 975 PB - Wiley-VCH GmbH CY - Weinheim AN - OPUS4-60464 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Robens-Radermacher, Annika A1 - Kujath, Cezary A1 - Bos, Freek A1 - Mechtcherine, Viktor A1 - Unger, Jörg F. T1 - Mechanical properties of 3D printed concrete: a RILEM TC 304-ADC interlaboratory study-Design and implementation of a database system for querying, sharing, and analyzing experimental data N2 - Interlaboratory studies are essential for implementing standardized test methods for new innovative materials or technologies such as 3D concrete printing, certifying reference materials, and validating methods. They provide the basis for recommendations and design standards. Typically, the collected data are used only for one study and are published in paper form, without open access to the raw data files. However, preserving the collected data and analysis procedures in a shareable and reusable way leads to advantages for further usage. New data with the same structure can be added or the data can be analyzed by a new analysis procedure generating new knowledge. Additionally, resources are saved by avoiding the repetition of the same measurements. In line with the recent digitalization trend in material science and engineering, a database for the interlaboratory study on mechanical properties of 3D printed concrete conducted in RILEM Technical Committee 304-ADC is established. The challenges and experiences from defining the data structure, uploading the data, and using the database for evaluations are discussed. The openBIS software is used to create and fill the database, while an export method to an SQLite format is developed and discussed to generate a shareable and reusable database. With the exported database, querying the data is possible independently of a particular data management system. Additionally, examples of data processing with reusable workflows automating the analysis procedure are demonstrated. KW - Data management KW - Interlaboratory study KW - 3D concrete printing KW - Database KW - Reusability PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-634627 DO - https://doi.org/10.1617/s11527-025-02650-9 SN - 1871-6873 VL - 58 IS - 184 SP - 1 EP - 37 PB - Springer Nature AN - OPUS4-63462 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wosniok, Aleksander A1 - Skoczowsky, Danilo A1 - Schukar, Marcus A1 - Pötzsch, Sina A1 - Pötschke, Samuel A1 - Krüger, Simone T1 - Fiber optic sensors for high-temperature measurements on composite tanks in fire N2 - For the purpose of increasing payload and reduce freight cost, lightweight composite tank containers used for Transportation have been progressively developed during the last years. Compared to conventionally produced cylindrical steel tanks, the fiber-reinforced solutions allow greater flexibility in the tank design. Despite a number of further material-related benefits of fiber-reinforced composites as non-conductive and non-magnetic behavior as well as corrosion resistance and high strength, the optimization of their thermal degradation properties during combustion is still a challenge. To improve the fire performance of lightweight composite containers, special intumescent fire protection coatings can be applied onto the outside tank surface. This paper presents fire tests on glass-fiber-reinforced plastic transport tanks with complex geometries sheltered with different surface-applied fire protection systems. To evaluate the fire resistance of the tank structures, a fiber optic monitoring system was developed. This system is based on distributed temperature measurements using high-Resolution optical backscatter reflectometry and pointwise reference measurements using fiber Bragg gratings. Thereby, all the fiber optic sensors were directly integrated in the composite layer structure of the tanks. The focus of the presented work is on the demonstration of capability of fiber optic monitoring system in such high-temperature application. Moreover, the fiber optic measurements provide new insights into the efficiency of intumescent coating applied for fire protection of fiber-reinforced plastic transport tanks. KW - Fire resistance KW - Composite material KW - Glass-fiber-reinforced plastic transport tank KW - Distributed fiber optic sensing KW - Optical backscatter reflectometry KW - Fiber optic sensor PY - 2019 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-481972 DO - https://doi.org/10.1007/s13349-019-00338-7 SN - 2190-5452 SN - 2190-5479 SP - 1 EP - 8 PB - Springer Nature AN - OPUS4-48197 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Babutzka, Martin A1 - Müller, Thoralf A1 - Mietz, Jürgen A1 - Burkert, Andreas T1 - Investigation of the influence of iron‐containing abrasives on the corrosion behaviour of the aluminium alloy AlSi1.2Mg0.4 N2 - The corrosion resistance of aluminium surfaces is closely linked to the surfacecstate after a grinding process. For years, iron‐containing abrasive materials were suspected to lead to increased corrosion susceptibility after processing of aluminium surfaces. To prove a possible correlation between the iron content of an abrasive and the corrosion behaviour of aluminium components, scientific investigations and experimentally practical corrosion tests are necessary. For the current investigation, specimens of a technical Al‐Si alloy from the same batch were used. The test specimens were mechanically ground with various resin‐bonded model abrasives containing different iron contents. The performed corrosion tests did not reveal a negative influence of the different iron‐containing abrasives on the corrosion behaviour of the Al–Si alloy. However, the most sensitive measuring method (electrochemical noise) showed differences in the surface activity depending on the type of abrasive. KW - Aluminium KW - Corrosion KW - Corrosion testing KW - Grinding PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-506762 DO - https://doi.org/10.1002/maco.202011657 SN - 0947-5117 SN - 1521-4176 VL - 71 IS - 10 SP - 1667 EP - 1679 PB - Wiley‐VCH Verlag GmbH & Co. KGaA CY - Weinheim AN - OPUS4-50676 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - RPRT A1 - Seifert, Lando A1 - Philipp, Markus A1 - Ebell, Gino A1 - Moersch, Jörg A1 - Müller, Thoralf T1 - Final report on WIPANO research project - A new test method for evaluating prestressing steels' susceptibility to stress corrosion cracking N2 - For the safety of prestressed concrete structures, a test of prestressing steel products for hydrogen-induced stress corrosion cracking is mandatory. The current standardized test methods according to DIN EN ISO 15630-3 have proven deficiencies concerning the reproducibility of the results and thus make it difficult to assess the susceptibility clearly. The WIPANO research project funded by BMWK aimed to improve the test method regarding reproducibility and reliability of results. The project created constant and reproducible test conditions by modifying material, electrolyte, and process parameters. This allowed a clear differentiation between good and bad products. As part of the project, a round robin test was initiated to confirm the applicability and reproducibility of the new test method. The new test method was evaluated for its applicability to the prestressing steel product wire. A draft standard with a proposed conformity criterion for these products was submitted to the responsible ISO committee for approval. According to the current feedback from the committee, the draft standard will be included in the informative annex of the testing standard, which could pave the way for mirroring at European and national standardization levels. KW - Prestressing steels KW - ISO 15630-3 KW - Hydrogen-induced stress corrosion cracking KW - Brittle fracture PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-581269 DO - https://doi.org/10.26272/opus4-58126 N1 - Funding source: Federal Ministry of Economic Affairs and Climate Action (BMWK), 11019 Berlin; FKZ: 03TNH019A/B/D SP - 1 EP - 106 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-58126 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Seher, Julia A1 - Rübner, Katrin A1 - Müller, Constanze A1 - Pniok, N. A1 - Dreisow, B. T1 - Leichte Gesteinskörnungen hergestellt aus Bau- und Abbruchabfällen – Applikation in der Denkmalpflege N2 - Im Rahmen des BMBF-geförderten Forschungsprojekts ReMin – REALight werden in einem Projektteam aus Industriepartnern und Forschungseinrichtungen unter Koordination der Bauhaus-Universität Weimar leichte Gesteinskörnungen aus Bau- und Abbruchabfällen und industriellen Nebenprodukten auf thermischem Weg hergestellt. Die Aufgabe der Bundesanstalt für Materialforschung und -prüfung (BAM) ist es, diese im Drehrohrofen erzeugten Blähgranulate für gebundene Anwendungen in Beton und Mörtel umfassend zu charakterisieren. Gemeinsam mit der Opus Denkmalpflege GmbH wird die Applikation feiner, gebrochener Blähgranulate in leichten Steinergänzungsmörteln für die Restaurierung von Sandsteinobjekten untersucht. Hierzu wird ein zweischichtiges Mörtelsystem bestehend aus einem Füll- und einem Deckmörtel entwickelt. Erste Ergebnisse der Rezepturentwicklung verschiedener kalkhaltiger Leichtmörtel mit gebrochenen Blähgranulaten werden vorgestellt. Die neuen Leichtmörtel sind hinsichtlich der entwickelten Druckfestigkeit gleichwertig gegenüber herkömmlichen Restauriermörteln. T2 - 21. Internationale Baustofftagung (ibausil) CY - Weimar, Germany DA - 13.09.2023 KW - Baustoffrecycling KW - Mauerwerkbruch KW - Leichte Gesteinskörnungen KW - Denkmalpflege KW - Restauriermörtel KW - Steinergänzungsmassen PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-590685 DO - https://doi.org/10.1002/cepa.2839 SN - 2509-7075 VL - 6 SP - 861 EP - 866 PB - Ernst & Sohn GmbH AN - OPUS4-59068 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF ED - Schraut, Katharina ED - Adamczyk, Burkart ED - Adam, Christian ED - Stephan, D. ED - Simon, Sebastian ED - von Werder, Julia ED - Meng, Birgit T1 - Production of a hydraulic material from post treated steelmaking slags N2 - Steelmaking slag is a by-product of steel production, of which 4.5 Mt were produced in 2020 in Germany alone. It is mainly used in road construction, earthwork and hydraulic engineering. A smaller part is returned to the metallurgical cycle, used as fertiliser or landfilled. With this use, iron oxides still contained in steelmaking slag are lost. In addition, the possibility of producing higher-grade products from steelmaking slag is foregone. In recent decades, many researchers have investigated the production of Portland cement clinker and crude iron from basic oxygen furnace slags (BOFS) via a reductive treatment. Carbothermal treatment of liquid BOFS causes a reduction of iron oxides to metallic iron, which separates from the mineral phase due to its higher density. Simultaneously, the chemical composition of the reduced slag is adapted to that of Portland cement clinker. In this study, German BOFS was reduced in a small-scale electric arc furnace using petrol coke as a reducing agent. The resulting low-iron mineral product has a similar chemical composition to Portland cement clinker and was rich in the tricalcium silicate solid solution alite (Ca3SiO5). Based on its chemical and mineralogical composition, similar to that of Portland cement clinker, the reduced BOFS has the potential to react comparably. In our study, the reduced BOFS produced less hydration heat than OPC, and its hydraulic reaction was delayed. However, adding gypsum has shown to accelerate the hydration rate of the reduced BOFS compared to that known from the calcium silicates of Portland cement clinker. Further research to improve the hydraulic properties of the reduced slag is essential. If successful, producing a hydraulic binder and crude iron from BOFS has economic and ecological benefits for both the cement and steel industries. T2 - The 16th International Congress on the Chemistry of Cement 2023 (ICCC2023) CY - Bangkok, Thailand DA - 18.09.2023 KW - Steelmaking slag KW - Alite KW - Clinker substitute KW - Hydraulic reactivity PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-590522 UR - https://www.iccc-online.org/archive/ SP - 432 EP - 436 CY - Bangkok AN - OPUS4-59052 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Herzel, Hannes A1 - Stemann, J. A1 - Simon, Sebastian A1 - Adam, Christian T1 - Comparison of thermochemical treatment of sewage sludge ash with sodium sulphate in laboratory-scale and pilot-scale experiments N2 - There is an ongoing debate on European scale concerning the criticality of phosphorus. In Switzerland and Germany, phosphorus recovery from phosphorus-rich waste streams will become obligatory. Sewage sludge ash is rich in phosphorus and may become an important secondary feedstock. Thermochemical treatment of sewage sludge ash with sodium sulphate under reducing conditions was shown to remove heavy metals from the solid product and produce the fully plant available crystalline phase CaNaPO4. Pilot-scale experiments in a rotary kiln were carried out at temperatures between 750 and 1000 °C and were compared to laboratory-scale experiments with crucibles. Process upscaling was successfully demonstrated but a series of differences were noticed: In comparison to laboratory-scale, solubility of phosphorus in samples from pilot-scale experiments was lower at all chosen treatment temperatures because of shorter retention time and incomplete decomposition of sodium sulphate. X-ray diffraction analysis revealed remaining phase fractions of whitlockite (Ca3-x(Mg,Fe)x(PO4)2) and sodium sulphate from the starting materials in products and thus indicated incomplete reaction. In contrast to the results of laboratory-scale experiments, the crystalline phase CaNaPO4 was clearly absent in the products from the rotary kiln but instead a Mg-bearing phase (Ca,Mg)NaPO4 was formed. Laboratory-scale experiments confirmed (Ca,Mg)NaPO4 is an intermediate phase between whitlockite and CaNaPO4. However, both crystalline phases are characterized by high plant availability. It was shown that heavy metal removal increased at higher temperatures whereas solubility and thus plant availability of phosphorus already reached its maxima at temperatures of 950 °C in pilot-scale and 875 °C in laboratory-scale experiments. KW - Crystalline phase identification KW - Heavy metal removal KW - Phosphorus availability KW - Process upscaling KW - Recovery KW - Rhenanite PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-524084 DO - https://doi.org/10.1007/s13762-021-03252-y VL - 19 IS - 3 SP - 1997 EP - 2006 PB - Springer AN - OPUS4-52408 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - RPRT A1 - Seifert, Lando A1 - Philipp, M. A1 - Ebell, Gino A1 - Moersch, J. A1 - Müller, Thoralf T1 - Gemeinsamer Schlussbericht zum Forschungsvorhaben - Entwicklung eines neuen Prüfverfahrens zur Beurteilung der Spannungsrisskorrosionsempfindlichkeit von Spannstählen für den Spannbetonbau N2 - Für die Sicherheit von Spannbetonbauwerken ist eine Empfindlichkeitsprüfung von Spannstahlprodukten gegenüber der wasserstoffinduzierten Spannungsrisskorrosion zwingend erforderlich. Die derzeitig normativ festgelegten Prüfmethoden nach DIN EN ISO 15630-3 zeigen nachweislich Schwächen hinsichtlich der Reproduzierbarkeit der Ergebnisse und erschweren damit die eindeutige Bewertung der Empfindlichkeit. Ziel des Forschungsvorhabens der Förderinitiative WIPANO des BMWK war es, die Prüfmethode hinsichtlich der Reproduzierbarkeit und Aussagesicherheit zu verbessern. Im Projekt wurden durch materialseitige, elektrolytische und verfahrenstechnische Parameteränderungen konstante und reproduzierbare Prüfbedingungen geschaffen. Dies ermöglichte eine eindeutige Differenzierung zwischen Gut- und Schlechtprodukten. Innerhalb des Projekts wurde ein Ringversuch initiiert, welcher die Anwendbarkeit und Reproduzierbarkeit der neuen Prüfmethode bestätigte. Das neue Prüfverfahren wurde hinsichtlich der Anwendbarkeit für das Spannstahlerzeugnis Draht evaluiert. Ein entsprechender Normentwurf mit einem Vorschlag für ein Konformitätskriterium dieser Erzeugnisse wurde dem zuständigen ISO-Gremium präsentiert und zur Abstimmung überlassen. Nach aktueller Rückmeldung seitens des Gremiums wird der Normentwurf den Eingang in den informativen Anhang der Prüfnorm finden, dies könnte den Weg für eine Spiegelung auf europäischer und nationaler Normungsebene ebnen. KW - Spannstahl KW - Spannungsrisskorrosion KW - ISO 15630-3 KW - Wasserstoff KW - Permeationsmessung KW - WIPANO PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-577922 DO - https://doi.org/10.26272/opus4-57792 SP - 1 EP - 106 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-57792 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Seifert, Lando T1 - Grundlagen Korrosion und Korrosionsschutz - Teil 2: Korrosionsschutz N2 - Im Rahmen der Fachausbildung "Kathodischer Korrosionsschutz (KKS)" fand als Pflichtmodul der Grundlagenkurs für erdverlegte Anlagen, Stahlbeton und Innenschutz statt. Im Vortrag (Teil 2 "Korrosionsschutz") wurden grundlegende Korrosionsschutzmethoden besprochen, welche sich aus dem Wissen über die Grundlagen der Korrosion ergeben. In einem 90 min Vortrag wurden planungs- und werkstoffseitige Vorgehensweisen präsentiert. Der normativ geregelte Korrosionsschutz bietet Regelwerke für verschiedene Umweltbedingungen und Metalle. Anhand einiger Beispiele wurden Normen zur Bestimmung der Korrosivität gezeigt und die Anforderungen an das spezifische Korrosionsschutzsystem erklärt. Schwerpunktmäßig ging es um den Schutz von Metallen in der Atmosphäre, in Erdböden und im Meerwasser. T2 - Grundlagenkurs für erdverlegte Anlagen, Stahlbeton und Innenschutz; Fachausbildung "Kathodischer Korrosionsschutz (KKS)" CY - Online meeting DA - 28.02.2023 KW - Korrosionsschutz KW - Werkstoffauswahl KW - Beschichtungssysteme KW - Deckschichten KW - nichtrostende Stähle KW - Galvanische Anoden KW - Vermeidung der Elementbildung PY - 2023 AN - OPUS4-57069 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schraut, Katharina T1 - Formation of tricalciumsilicate from post-treated metallurgical slags N2 - LD-slags differ from Ordinary Portland Cement (OPC) mainly in a higher content of iron oxides and a low content of Tricalciumsilicate (Alite). In the context of an improved resource usage, a procedure to convert LDslags into cement clinker was investigated. T2 - 15th International Congress on the Chemistry of Cement CY - Prague, Czech Republic DA - 16.09.2019 KW - Tricalcium-silicate KW - Portland Cement KW - Alite KW - Steelmaking slag PY - 2019 AN - OPUS4-49591 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schmidt, Wolfram A1 - Cunnigham, P. R. A1 - Shaba, A. F. A1 - Olonade, K. A. A1 - Ndawula, J. A1 - Tawiah, A. T. A1 - Marangu, J. M. A1 - Tlhatlha, Pheladi A1 - Obeng, E. ED - Banhia, N. T1 - Informal Sector Inclusion in Sustainable Concrete Construction in Africa N2 - Concrete used as a construction material is inevitable in Africa’s rapid urban growth, despite its significant contribution to carbon emissions. Hence, best practice concrete with reduced Portland cement clinker needs to be applied. The highly informal nature ofAfrica’s construction sector could impede the implementation of sustainable concrete construction. Although urgent need for economisation unintentionally often leads informal actors to operate according to circularity principles, the sector lacks awareness of climate challenges and incentives for adopting climate-friendly materials and technologies. In addition, the informal sector is prone to fraudulent adulterated materials and components causing challenges for safe and durable construction. The authors elaborate on the crucial role of the informal sector in driving sustainable construction forward, despite the lack of policies and disinterest from regulatory bodies. Solutions through education, communication, and quality control are proposed and discussed. T2 - 77th RILEM Annual Week and the 1st Interdisciplinary Symposium on Smart & Sustainable Infrastructures (ISSSI 2023) CY - Vancouver, Canada DA - 04.09.2023 KW - Cement testing KW - Hydration KW - Economic development KW - Informal sector KW - Cement chemistry PY - 2024 SN - 978-3-031-53391-4 DO - https://doi.org/10.1007/978-3-031-53389-1_47 VL - 48 SP - 506 EP - 520 PB - Springer Nature Switzerland AG CY - Schweiz AN - OPUS4-61586 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schmidt, Wolfram T1 - Policies and codes for sustainable cement and concrete technologies in the Global South N2 - This paper explores three primary pathways for improving sustainable cement and concrete technologies: cement production, concrete production, and recycling technologies. It underscores the importance of policy frameworks for transitioning from prescriptive to performance-based standards to foster innovation and support low-carbon technologies, while also addressing the economic, political, and social drivers that shape policy and industry practices. The research questions the replication of Global North standards in the Global South, advocating for locally adapted, unique regional policies. T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM Green Intelligent Building CY - Berlin, Germany DA - 16.10.2024 KW - Sustainable cement KW - Concrete technologies KW - Africa KW - Labour cost KW - Quality Infrastructure KW - Global South PY - 2024 AN - OPUS4-61802 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Baeßler, Matthias A1 - Kannengießer, Thomas T1 - Aktivitäten in Forschung und Zulassung im Bereich Windenergie N2 - Die vielfältigen Tätigkeiten der BAM im Bereich technischer Sicherheit von Windenergieanlagen werden vorgestellt und im Bereich aktueller Entwicklungen in der Fügetechnik detailliert. T2 - Arbeitskreis Gründungsstrukturen und Stahlbau der WAB CY - Online meeting DA - 13.04.2021 KW - BAM Windenergie Fügetechnik PY - 2021 AN - OPUS4-53026 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Fini, E. H. A1 - Poulikakos, L. A1 - de Claville Christiansen, J. A1 - Schmidt, Wolfram A1 - Parast, M. M. T1 - Toward sustainability in the built environment: An integrative approach N2 - The built environment significantly impacts the health of individuals and populations in various ways. The health and durability of the built environment are intertwined with availability ofnaturally occurring and man-made resources and their supply chains. Therefore, resource con­ servation is a key to ensure sustainability of built environments. Many industrial wastes can be turned into valuable resources for reuse in construction of the built environment. For instance, biowaste (woody/ leafy biomass and animal waste) have been used to make construction adhesives (Fini et al., 2011), some urban wastes have been used in road construction (Poulikakos et al., 2017; Schmidt et al., 2021), end of life plastics and polymers have made their way to roadway construction, bio-oils and algae harvested from wastewater treatment plants has been used to make antiaging for outdoor building elements to mitigate UV aging (Kabir et al., 2021); sulfur has been used as an extender in asphalt and recycled mineral powders such as silica and alumina have been used to increase strength and durability against acidic compounds (Fini et al., 2019). These are just a few examples of recycling venues with beneficial uses in the built environment. The construction and operation of the built environment and the traffic that it attracts or facilitates significantly contribute to the emis­ sion of greenhouse gasses (GHG) and cause air pollution. The direct and indirect impacts of GHG and air pollutants on the environment and so­ cieties have been weil established. The built environment can be used as a powerful platform not only for recycling and resource conservation but also to remove near-ground gaseous contaminants. This can be done via tailored design and engineering of adsorptive construction materials via recycling of waste materials. For instance, advanced sorbent systems can be made for removing C02, H2S, and formaldehyde from air. This re­ quires tailored sorbent design, topology optimization, and catalytic conversion of collected gaseous compounds to name a few. This special issue covers innovative materials, methods, and man­ agement practices which aim to simultaneously address durability ofthe built environment, air quality, resource conservation, and supply chain resilience. Such innovative materials, methods, and management prac­ tices will transform the built environment into not only an active contributor to no waste, no pollution for healthy environment, but also a medium that converts the waste and pollution into beneficial products for use in the built environment, thereby promoting resource conser­ vation. Followings are examples of topics that the special issue is interested in: • Venuses to advance resource conservation specifically via novel ap­ proaches in the built environment. • Innovative construction materials for passive or active adsorption of harmful gaseous emissions to conserve air, energy, and water. • Advanced materials, methods, and management practices to pro­ mote well-being of the built environment. • Smart buildings to promote resource conservation. • Research convergence in the built environment for zero waste, zero pollution economy. KW - Impacts KW - Resource PY - 2021 DO - https://doi.org/10.1016/j.resconrec.2021.105676 VL - 172 SP - 1 EP - 2 PB - Elsevier AN - OPUS4-58402 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kruschwitz, Sabine T1 - Investigation of the hydration of clinker-reduced cementitious binders by 1H NMR N2 - In this paper, we demonstrate the value of 1H NMR relaxometry for studying the hydration of clinker-reduced, more climate-friendly cementitious binders. The results were obtained on typical CEM I cements and samples containing two different reactive agricultural ashes as well as non-reactive biochars as supplementary cementitious materials. The findings prove that time-resolved NMR measurements provide valuable additional information when combined with classical heat flow calorimetry. T2 - ISEMA Down Under 2023 CY - Brisbane, Australia DA - 25.09.2023 KW - 1H NMR relaxometry KW - Heat flow calorimetry KW - Clinker reduction, carbon emission KW - Cement KW - Hydration PY - 2023 AN - OPUS4-58569 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - de Carvello, J. M. F. A1 - Schmidt, Wolfram A1 - Kühne, Hans-Carsten A1 - Fiorotti Peixoto, R. A. T1 - Influence of high-charge and low-charge PCE-based superplasticizers on Portland cement pastes containing particle-size designed recycled mineral admixtures N2 - Design : and use of engineered recycled mineral admixtures obtained from industrial and mineral waste are promising strategies to increase the range of materials suitable for use in cement-based composites. In this work, Portland cement-blended pastes containing mineral admixtures designed for improving particle packing were evaluated in the presence of low- and high-charge polycarboxylate-based superplasticizers. The powders were obtained from basic oxygen furnace slag, iron ore tailings, quartz mining tailings, and quartzite mining tailings. The zeta-potentials of the particles were obtained via electrophoretic mobility. The flow properties were evaluated by rheological tests performed in a Couette type rheometer. The hydration kinetics was evaluated by isothermal calorimetry and an adapted method based on the Vicat needle test. The high-charge PCE and the finer mineral admixtures produced more stable blends. Coarser mineral admixtures led to increased flowability and delayed hydration compared to finer ones. Steel slag powders presented the most significant plasticizer effects, but also the largest setting delays and segregation tendency. Quartz-rich superfines reduced the setting delays caused by the superplasticizers. In summary, both superplasticizers were effective in improving flow properties, but the high-charge PCE was effective in preventing segregation in pastes containing mineral admixtures coarser and heavier than cement. KW - Engineered recycled mineral admixtures KW - Rheology KW - PCE-Based superplasticizer KW - Steel slag KW - Mining tailing PY - 2020 DO - https://doi.org/10.1016/j.jobe.2020.101515 VL - 32 SP - 1 EP - 16 PB - Elsevier AN - OPUS4-58395 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Müller, Thoralf T1 - Korrosionsschutz-Dauerhaftigkeit als Herausforderung für die Ewigkeit N2 - Technische Infrastruktur umfasst unter anderem Straßen, Brücken, Flughäfen, Telekommunikationsnetze und alle Systeme der Energieversorgung. Alle Anlagen in diesen Bereichen erfordern hohe finanzielle Investitionen und sollen für Jahrzehnte der Nutzung ausgelegt sein. Dieser Anspruch kann nur dann erfüllt werden, wenn die Anlagen und die darin erhaltenen Ausstattungen korrosionssicher ausgelegt werden; d.h. Korrosionsschäden während der Nutzung ausgeschlossen werden können. Es werden Vorschläge für eine sachgerechte Auswahl von Maßnahmen zum Korrosionsschutz in verschiedenen Anwendungsbereichen dargestellt und beachtenswerte Parameter für eine kompetente Gestaltung der Korrosionsschutzmaßnahmen erläutert. T2 - fkss Infotag 02/2023 CY - Berlin, Germany DA - 06.07.2023 KW - Korrosionsschutz KW - Dauerhaftigkeit KW - Korrosionsprüfung KW - Atmosphärische Korrosion PY - 2023 AN - OPUS4-57869 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Nikoonasab, Ali T1 - Electrochemical study of steel reinforcement in the synthetic pore solution of alkali-activated binders: Pore solution composition N2 - It is well known that cement manufacture, including CaCO3 calcination and clinker formation, is associated with substantial energy consumption and significant greenhouse gas emissions. Alkali-activated binders (AAB) and concretes made from them can significantly contribute to reducing CO2 emissions caused by the construction industry. However, to what extent and for how long concretes made from AAB can protect the steel in reinforced concrete components from corrosion is still unclear. Unlike PC-based binders, AABs are made by reacting alkaline solutions with solid precursors such as fly ash and ground granulated blast furnace slag (GGBFS). Therefore, steel reinforcement corrosion mechanisms in AAMs differ from PC-based binders. The present study aims to evaluate the corrosion behavior of steel rebar in alkali-activated materials (AAMs) synthetic pore solution with different chemical concentrations representing different GGBFS and Flay Ash based binders by performing electrochemical tests to measure the corrosion rate and corrosion potential of steel rebar. This information can be used to improve the design of AAMs in order to ensure a longer service life for these materials. T2 - Eurocorr2023 CY - Brussels, Belgium DA - 27.08.2023 KW - GGBFS KW - AAM KW - Sulfide KW - Pore solution composition KW - Redox potential KW - Corrosion PY - 2023 AN - OPUS4-59090 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kruschwitz, Sabine A1 - Lorenzoni, Renata A1 - Telong, Melissa A1 - Lauinger, Robert A1 - Munsch, Sarah Mandy A1 - Schmidt, Wolfram T1 - Investigation of the hydration of clinker-reduced cementitious binders by 1H NMR N2 - In this paper, we demonstrate the value of 1H NMR relaxometry for studying the hydration of clinker-reduced, more climate-friendly cementitious binders. The results were obtained on typical CEM I cements and sister samples containing two different reactive agricultural ashes as well as non-reactive biochars as supplementary cementitious materials. The findings prove that time-resolved NMR measurements provide valuable additional information when combined with classical heat flow calorimetry. T2 - International Conference on Electromagnetic Wave Interaction with Water and Moist Substances of the International Society for Electromagnetic Aquametry (ISEMA) 2023 CY - Brisbane, Ausralia DA - 25.09.2023 KW - Carbon emission KW - 1H NMR relaxometry KW - Heat flow calorimetry KW - Cement, hydration KW - Clinker reduction PY - 2023 SP - 1 EP - 3 AN - OPUS4-58936 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Pittrich, Tim A1 - Weise, Frank A1 - Stelzner, Ludwig T1 - The impact of blended cements on the spalling behavior of concrete at elevated temperatures: a review N2 - The cement and concrete industries are striving to reduce the CO2 emissions caused by the production of Portland cement. An effective way to achieve this is to replace Portland cement clinker with more environmentally friendly supplementary cementitious materials (SCMs) to produce blended cements. A variety of different SCMs are used today, from fly ash to more exotic options such as rice husk ash or waste glass powder. Depending on its material properties, concrete exposed to fire may experience spalling caused by thermomechanical and thermohydraulic mechanisms. Severe spalling leads to a reduction in the cross-section and exposure of the reinforcement, jeopardizing the load-bearing capacity of the concrete element. The use of blended cements changes the concrete properties which can affect spalling behavior at high temperatures. The link between high temperature and spalling behavior of concrete with blended cements has been investigated in several studies. A review of the existing literature led to the conclusion that the cement type influences the spalling behavior of concrete. However, the relationship does not appear to be clear, as there are contradictions and inconsistencies between the evaluated results. Therefore, further in-depth studies will help to gain a more precise understanding of the effects of blended cements on the spalling behavior of concrete at elevated temperatures. KW - Fire-induced concrete spalling KW - Concrete KW - Blended cements KW - SCM KW - Filler PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-635182 DO - https://doi.org/10.1617/s11527-025-02713-x SN - 1359-5997 VL - 58 IS - 5 SP - 1 EP - 21 PB - Springer Science and Business Media LLC AN - OPUS4-63518 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wolfs, Rob A1 - Versteegen, Jelle A1 - Santhanam, Manu A1 - Bhattacherjee, Shantanu A1 - Bos, Freek A1 - Robens-Radermacher, Annika A1 - Muthukrishnan, Shravan A1 - Menna, Costantino A1 - Ozturk, Onur A1 - Ozyurt, Nilufer A1 - Roupec, Josef A1 - Richter, Christiane A1 - Jungwirth, Jörg A1 - Miranda, Luiza A1 - Ammann, Rebecca A1 - Caron, Jean-François A1 - de Bono, Victor A1 - Monte, Renate A1 - Navarrete, Iván A1 - Eugenin, Claudia A1 - Lombois‑Burger, Hélène A1 - Baz, Bilal A1 - Sinka, Maris A1 - Sapata, Alise A1 - Harbouz, Ilhame A1 - Zhang, Yamei A1 - Jia, Zijian A1 - Kruger, Jacques A1 - Mostert, Jean‑Pierre A1 - Šter, Katarina A1 - Šajna, Aljoša A1 - Kaci, Abdelhak A1 - Rahal, Said A1 - Snguanyat, Chalermwut A1 - Arunothayan, Arun A1 - Zhao, Zengfeng A1 - Mai, Inka A1 - Rasehorn, Inken Jette A1 - Böhler, David A1 - Freund, Niklas A1 - Lowke, Dirk A1 - Neef, Tobias A1 - Taubert, Markus A1 - Auer, Daniel A1 - Hechtl, C. Maximilian A1 - Dahlenburg, Maximilian A1 - Esposito, Laura A1 - Buswell, Richard A1 - Kolawole, John A1 - Isa, Muhammad Nura A1 - Liu, Xingzi A1 - Wang, Zhendi A1 - Subramaniam, Kolluru A1 - Mechtcherine, Viktor T1 - Mechanical properties of 3D printed concrete: a RILEM TC 304-ADC interlaboratory study — flexural and tensile strength N2 - This paper discusses the flexural and tensile strength properties of 3D printed concrete, based on the results of a RILEM TC 304-ADC interlaboratory study on mechanical properties. These properties are determined using different testing techniques, including 3- and 4-point flexural tests, splitting tests, and uniaxial tension tests, on specimens extracted from large 3D printed elements in accordance with a prescribed study plan. The relationship between compressive and flexural or tensile strengths, cast or printed samples, different types of tests, and different loading orientations, are analysed to understand the influence of 3D printing. As expected, the strength can reduce significantly when the main tensile stress is acting perpendicular to the interface between layers. The role of deviations from the standard study procedure, in terms of the time interval between the placing of subsequent layers, or the adoption of a different curing strategy, are also assessed. While the increased time interval significantly impacts the strength in the critical direction, the use of variable curing conditions does not seem to have a clear-cut effect on the strength ratios of the printed to cast specimens. Additionally, the paper looks at the variability in the results for the printed specimens, in order to emphasize the need for multiple replicates for obtaining a proper result. An extensive insight into the aspects affecting the variability is presented in the paper. Finally, with the limited dataset available for specimens tested at a larger scale, it is difficult to arrive at a clear understanding of the role of specimen size (i.e., greater number of layers). KW - 3D concrete printing KW - Digital fabrication KW - Flexural strength KW - Tensile strength KW - Interlayer bond strength PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-634655 DO - https://doi.org/10.1617/s11527-025-02687-w SN - 1871-6873 VL - 58 IS - 5 SP - 1 EP - 33 PB - Springer Nature AN - OPUS4-63465 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Mechtcherine, Viktor A1 - Muthukrishnan, Shravan A1 - Robens-Radermacher, Annika A1 - Wolfs, Rob A1 - Versteege, Jelle A1 - Menna, Costantino A1 - Ozturk, Onur A1 - Ozyurt, Nilufer A1 - Roupec, Josef A1 - Richter, Christiane A1 - Jungwirth, Jörg A1 - Miranda, Luiza A1 - Ammann, Rebecca A1 - Caron, Jean‑François A1 - de Bono, Victor A1 - Monte, Renate A1 - Navarrete, Iván A1 - Eugenin, Claudia A1 - Lombois‑Burger, Hélène A1 - Baz, Bilal A1 - Sinka, Maris A1 - Sapata, Alise A1 - Harbouz, Ilhame A1 - Zhang, Yamei A1 - Jia, Zijian A1 - Kruger, Jacques A1 - Mostert, Jean‑Pierre A1 - Štefančič, Mateja A1 - Hanžič, Lucija A1 - Kaci, Abdelhak A1 - Rahal, Said A1 - Santhanam, Manu A1 - Bhattacherjee, Shantanu A1 - Snguanyat, Chalermwut A1 - Arunothayan, Arun A1 - Zhao, Zengfeng A1 - Mai, Inka A1 - Rasehorn, Inken Jette A1 - Böhler, David A1 - Freund, Niklas A1 - Lowke, Dirk A1 - Neef, Tobias A1 - Taubert, Markus A1 - Auer, Daniel A1 - Hechtl, C. Maximilian A1 - Dahlenburg, Maximilian A1 - Esposito, Laura A1 - Buswell, Richard A1 - Kolawole, John A1 - Isa, Muhammad Nura A1 - Liu, Xingzi A1 - Wang, Zhendi A1 - Subramaniam, Kolluru A1 - Bos, Freek T1 - Mechanical properties of 3D printed concrete: a RILEM 304-ADC interlaboratory study – compressive strength and modulus of elasticity N2 - Traditional construction techniques, such as in-situ casting and pre-cast concrete methods, have well-established testing protocols for assessing compressive strength and modulus of elasticity, including specific procedures for sample preparation and curing. In contrast, 3D concrete printing currently lacks standardized testing protocols, potentially contributing to the inconsistent results reported in previous studies. To address this issue, RILEM TC 304-ADC initiated a comprehensive interlaboratory study on the mechanical properties of 3D printed concrete. This study involves 30 laboratories worldwide, contributing 34 sets of data, with some laboratories testing more than one mix design. The compressive strength and modulus of elasticity were determined under three distinct conditions: Default, where each laboratory printed according to their standard procedure followed by water bath curing; Deviation 1, which involved creating a cold joint by increasing the time interval between printing layers; and Deviation 2, where the standard printing process was used, but the specimens were cured under conditions different from water bath. Some tests were conducted at two different scales based on specimen size—“mortar-scale” and “concrete-scale”—to investigate the size effect on compressive strength. Since the mix design remained identical for both scales, the only variable was the specimen size. This paper reports on the findings from the interlaboratory study, followed by a detailed investigation into the influencing parameters such as extraction location, cold joints, number of interlayers, and curing conditions on the mechanical properties of the printed concrete. As this study includes results from laboratories worldwide, its contribution to the development of relevant standardized testing protocols is critical. KW - Additive manufacturing KW - Digital fabrication KW - Hardened concrete KW - Compressive strength KW - Young's modulus PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-634672 DO - https://doi.org/10.1617/s11527-025-02688-9 SN - 1871-6873 VL - 58 IS - 5 SP - 1 EP - 30 PB - Springer Nature AN - OPUS4-63467 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kossatz, Philipp T1 - Upconversion Nanoparticles as Luminescent Probes for Cement N2 - Safety is a key parameter for the design and construction of buildings. The most widely used construction material to date is concrete that consists of about 15-20 wt.-% cement, which is responsible for the main concrete properties, i.e., strength and durability. Despite many standards regulating the quality of cement, at present, there exists no viable method to track the cement life cycle “from cradle to grave”. This led to an increasing interest in simple and robust methods for studying the processes and changes occurring during the life cycle of cement. In this context, we explored the applicability of fluorescence measurements which can be performed with relatively inexpensive and miniaturized instrumentation yet require robust optical probes which survive the harsh cement environment. Therefore, we developed a platform of lanthanide-based upconversion nanoparticles (UCNPs), consisting of a NaYF4 matrix doped with Yb3+ and Er3+ with sizes between 20 nm and 55 nm, which show characteristic multi-color emission patterns, composed of narrow bands of varying intensity in the ultraviolet, visible, near-infrared, and short-wave spectral region and examined their potential for cement probing and the non-invasive monitoring of the hydration processes occurring during cement formation. UCNPs of different size and chemical composition were synthesized via a thermal decomposition approach under inert conditions. The tailor-made design of different emission patterns was achieved by tuning particle size and morphology, material composition, and particle surface chemistry in upscaleable syntheses. For cement probing, different types of UCNPs were added to cement and the evolution of the UCNP emission pattern was used to probe in-situ changes of physico-chemical parameters in the cementitious environment during hydration, utilizing a simple and portable custom-designed optical setup. The observed changes in the UCNP emission patterns are characteristic for a given particle size, surface chemistry, and cement composition. In addition to fluorescence measurements, conventional isothermal heat flow calorimetry was used to study the influence of UCNP addition on cement hydration kinetics. Subsequently, both sets of measurements were correlated. Our results underline the potential of our optical approach ad UCNPs for the non-invasive probing of cementitious systems and cement hydration. This can be also exploited for cutting-edge applications of construction materials such as 3D concrete printing. T2 - Summer School Exciting Nanostructures CY - Bad Honnef, Germany DA - 31.07.2023 KW - Cement Hydration KW - Upconversion KW - Fluorescence Spectroscopy PY - 2023 AN - OPUS4-58203 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Strobl, Dominic T1 - Reduced Order Model with Domain Mapping for Temperature Field Simulation of Wire Arc Additive Manufacturing N2 - Additive manufacturing (AM) has revolutionized the manufacturing industry, offering a new paradigm to produce complex geometries and parts with customized properties. Among the different AM techniques, the wire arc additive manufacturing (WAAM) process has gained significant attention due to its high deposition rate and low equipment cost. However, the process is characterized by a complex thermal history, dynamic metallurgy, and mechanical behaviour that make it challenging to simulate it in real-time for online process control and optimization. In this context, a reduced order model (ROM) using the proper generalized decomposition (PGD) method is proposed as a powerful tool to overcome the limitations of conventional numerical methods and enable the real-time simulation of the temperature field of WAAM processes. Though, the simulation of a moving heat source leads to a hardly separable parametric problem, which is handled by applying a novel mapping approach. Using this procedure, it is possible to create a simple separated representation of the model, also allowing to simulate multiple layers. In this contribution, a PGD model is derived for the WAAM procedure simulating the temperature field. A good agreement with a standard finite element method is shown. The reduced model is further used in a stochastic model parameter estimation using Bayesian inference, speeding up calibrations and ultimately leading to a calibrated real-time simulation. T2 - SIM-AM 2023 CY - Munich, Germany DA - 26.07.2023 KW - Additive manufacturing KW - Reduced Order Model PY - 2023 AN - OPUS4-58253 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Strobl, Dominic A1 - Unger, Jörg F. A1 - Chady, G. A1 - Klawoon, Alexander A1 - Pittner, Andreas A1 - Rethmeier, Michael A1 - Robens-Radermacher, Annika T1 - Efficient bead-on-plate weld model for parameter estimation towards effective wire arc additive manufacturing simulation N2 - Despite the advances in hardware and software techniques, standard numerical methods fail in providing real-time simulations, especially for complex processes such as additive manufacturing applications. A real-time simulation enables process control through the combination of process monitoring and automated feedback, which increases the flexibil- ity and quality of a process. Typically, before producing a whole additive manufacturing structure, a simplified experiment in form of a bead-on- plate experiment is performed to get a first insight into the process and to set parameters suitably. In this work, a reduced order model for the transient thermal problem of the bead-on-plate weld simulation is devel- oped, allowing an efficient model calibration and control of the process. The proposed approach applies the proper generalized decomposition (PGD) method, a popular model order reduction technique, to decrease the computational effort of each model evaluation required multiple times in parameter estimation, control and optimization. The welding torch is modeled by a moving heat source, which leads to difficulties separating space and time, a key ingredient in PGD simulations. A novel approach for separating space and time is applied and extended to 3D problems allowing the derivation of an efficient separated representation of the tem- perature. The results are verified against a standard finite element model showing excellent agreement. The reduced order model is also leveraged in a Bayesian model parameter estimation setup, speeding up calibrations and ultimately leading to an optimized real-time simulation approach for welding experiment using synthetic as well as real measurement data. KW - Ermüdung PY - 2023 DO - https://doi.org/10.5281/zenodo.7456813 PB - Zenodo CY - Geneva AN - OPUS4-59651 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Strobl, Dominic T1 - PGD model with domain mapping of Bead-on-Plate weld simulation for wire arc additive manufacturing N2 - Numerical simulations are essential in predicting the behavior of systems in many engineering fields and industrial sectors. The development of accurate virtual representations of actual physical products or processes allows huge savings in cost and resources. In fact, digital twins would allow reducing the number of real, physical prototypes, tests, and experiments, thus also increasing the sustainability of the production processes and products’ lifetime. Standard numerical methods fail in providing real time simulations, especially for complex processes such as additive manufacturing applications. This work aims to build up a reduced order model for efficient wire arc additive manufacturing simulations by using the proper generalized decomposition (PGD) [1,2] method. Model order reduction is a popular concept to decrease the computational effort, where each evaluation of the reduced forward model is faster than evaluations using classical methods, even for complex models. The simulation of a moving heat source leads to a hardly separable parametric problem, which is solved by a new mapping approach [3]. Using this procedure, it is possible to create a simple separated representation of the forward model. In this contribution, a PGD model is derived for the first part of wire arc additive manufacturing: bead-on-plate weld. An excellent agreement with a standard finite element method is shown. The reduced model is further used in a model calibration set up, speeding up calibrations and ultimately leading to an optimized real-time simulation. T2 - The 8th European Congress on Computational Methods in Applied Sciences and Engineering (ECCOMAS) 2022 CY - Oslo, Norway DA - 05.06.2022 KW - PGD KW - Model calibration KW - Hardly separable problem KW - Additive manufacturing PY - 2022 AN - OPUS4-55111 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Strobl, Dominic T1 - Real-time Bead-on-Plate weld Simulation for Wire Arc Additive Manufacturing using Reduced Order modelling coupled with stochastic model Calibration N2 - Numerical simulations are essential in predicting the behavior of systems in many engineering fields and industrial sectors. The development of accurate virtual representations of actual physical products or processes (also known as digital twins) allows huge savings in cost and resources. In fact, digital twins would allow reducing the number of real, physical prototypes, tests, and experiments, thus also increasing the sustainability of production processes and products’ lifetime. Standard numerical methods fail in providing real time simulations, especially for complex processes such as additive manufacturing applications. This work aims to use a reduced order model for efficient wire arc additive manufacturing simulations, calibrations and real-time process control. Model reduction, e.g. the proper generalized decomposition [1,2] method, is a popular concept to decrease the computational effort. A new mapping approach [3] was applied to simulate a moving heat source with the proper generalized decomposition. Using this procedure even complex models can be simulated in real-time. The physical model is later on calibrated with the use of a stochastic model updating process and the reduced order model, leading to an optimized real-time simulation. In this contribution, a proper generalized decomposition model for a bead-on-plate wire arc additive manufacturing is presented. It is also coupled with a stochastic model updating process identifying the heat source characteristics as well as the boundary conditions of the transient thermal problem, whereas the heat source shape is simulated using a Goldak heat source T2 - 15th World Congress on Computational Mechanics (WCCM-XV) CY - Yokohama, Japan DA - 31.07.2022 KW - Wire arc additive manufacturing KW - Reduced order modelling KW - Model calibration PY - 2022 AN - OPUS4-55576 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Liao, Chun-Man T1 - Assessment of prestress loss in a large-scale concrete bridge model under outdoor condition N2 - The presentation shows that subtle variations in coda wave velocity can capture minor temperature effects, offering a good understanding of how a outdoor prestressed concrete structure responds to environmental conditions over time. Ultimately, this work contributes to development of more comprehensive and resilient structural health monitoring strategies for prestressed concrete infrastructure. T2 - EVACES 2025 CY - Porto, Portugal DA - 02.07.2025 KW - Coda wave interferometry KW - Damage detection KW - Prestress loss KW - Seismic interferometry KW - Structural health monitoring PY - 2025 AN - OPUS4-64211 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kazlagić, Anera A1 - Russo, Francesco A1 - Vogl, Jochen A1 - Sturm, Patrick A1 - Stephan, D. A1 - Gluth, Gregor ED - Resch-Genger, Ute ED - Koch, Matthias ED - Meermann, Björn ED - Weller, Michael G. T1 - Development of a sample preparation procedure for Sr isotope analysis of Portland cements N2 - The 87Sr/86Sr isotope ratio can, in principle, be used for provenancing of cement. However, while commercial cements consist of multiple components, no detailed investigation into their individual 87Sr/86Sr isotope ratios or their influence on the integral 87Sr/86Sr isotope ratio of the resulting cement was conducted previously. Therefore, the present study aimed at determining and comparing the conventional 87Sr/86Sr isotope ratios of a diverse set of Portland cements and their corresponding Portland clinkers, the major component of these cements. Two approaches to remove the additives from the cements, i.e. to measure the conventional 87Sr/86Sr isotopic fingerprint of the clinker only, were tested, namely, treatment with a potassium hydroxide/sucrose solution and sieving on a 11-µm sieve. Dissolution in concentrated hydrochloric acid/nitric acid and in diluted nitric acid was employed to determine the 87Sr/86Sr isotope ratios of the cements and the individual clinkers. The aim was to find the most appropriate sample preparation procedure for cement provenancing, and the selection was realised by comparing the 87Sr/86Sr isotope ratios of differently treated cements with those of the corresponding clinkers. None of the methods to separate the clinkers from the cements proved to be satisfactory. However, it was found that the 87Sr/86Sr isotope ratios of clinker and cement generally corresponded, meaning that the latter can be used as a proxy for the clinker 87Sr/86Sr isotope ratio. Finally, the concentrated hydrochloric acid/nitric acid dissolution method was found to be the most suitable sample preparation method for the cements; it is thus recommended for 87Sr/86Sr isotope analyses for cement provenancing. KW - Cement KW - Provenancing KW - Sr isotopes KW - Portland clinker KW - Dissolution PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-542239 DO - https://doi.org/10.1007/s00216-021-03821-7 SN - 1618-2642 SN - 1618-2650 VL - 414 IS - 15 (Topical collection: Analytical methods and applications in the materials and life sciences) SP - 4379 EP - 4389 PB - Springer CY - Berlin AN - OPUS4-54223 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Strommer, Bettina A1 - Battig, Alexander A1 - Schulze, Dietmar A1 - Agudo Jácome, Leonardo A1 - Schartel, Bernhard A1 - Böhning, Martin T1 - Shape, orientation, interaction, or dispersion: valorization of the influence factors in natural rubber nanocomposites N2 - The addition of nanoparticles as reinforcing fillers in elastomers yields nanocomposites with unique property profiles, which opens the door for various new application fields. Major factors influencing the performance of nanocomposites are studied by varying the type and shape of nanoparticles and their dispersion in the natural rubber matrix. The industrial applicability of these nanocomposites is put into focus using two types of graphene and a nanoscale carbon black, all commercially available, and scalable processing techniques in the form of a highly filled masterbatch production via latex premixing by simple stirring or ultrasonically assisted dispersing with surfactant followed by conventional two-roll milling and hot pressing. Different processing and measurement methods reveal the potential for possible improvements: rheology, curing behavior, static and dynamic mechanical properties, swelling, and fire behavior. The aspect ratio of the nanoparticles and their interaction with the surrounding matrix prove to be crucial for the development of superior nanocomposites. An enhanced dispersing method enables the utilization of the improvement potential at low filler loadings (3 parts per hundred of rubber [phr]) and yields multifunctional rubber nanocomposites: two-dimensional layered particles (graphene) result in anisotropic material behavior with strong reinforcement in the in-plane direction (157% increase in the Young's modulus). The peak heat release rate in the cone calorimeter is reduced by 55% by incorporating 3 phr of few-layer graphene via an optimized dispersing process. KW - Graphene KW - Natural rubber KW - Nanocomposites KW - Anisotropy KW - Fire behavior PY - 2023 DO - https://doi.org/10.5254/rct.23.77961 SN - 0035-9475 SN - 1943-4804 VL - 96 IS - 1 SP - 40 EP - 58 PB - Allen Press CY - Lawrence (KA), USA AN - OPUS4-57568 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kossatz, Philipp A1 - Mezhov, Alexander A1 - Andresen, Elina A1 - Schmidt, Wolfram A1 - Resch-Genger, Ute T1 - Application of fluorescence spectroscopy for the monitoring of cement hydration N2 - Lanthanide-based upconversion nanoparticles (UCNPs) with size- and morphology-dependent emission patterns, composed of narrow bands of varying intensity in the ultraviolet, visible, near-infrared, and short-wave infrared wavelength region, were synthesized via a thermal decomposition approach under inert atmosphere. Subsequently, differently sized UCNPs were incorporated into ordinary Portland cement to study their stability in the harsh cementitious environment and assess their potential for the probing and monitoring of cement hydration. Microenvironment-specific changes in the emission properties of these inorganic luminophores were utilized to study and probe changes of physico-chemical parameters during cement hydration. Isothermal calorimetry was employed to better understand the influence of luminophore addition on cement hydration kinetics and for the correlation with the results of the optical studies. T2 - 12th ACI/RILEM International Conference on Cementitious Materials and Alternative Binders for Sustainable Concrete (ICCM 2024) CY - Toulouse, France DA - 23.06.2024 KW - Luminescence KW - Optical probe KW - Cement hydration PY - 2024 UR - https://www.iccm2024.com/ SP - 441 EP - 446 CY - Toulouse, France AN - OPUS4-62119 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Strobl, Domninic T1 - Reduced order model for temperature field simulation of wire arc additive manufacturing N2 - Additive manufacturing (AM) has revolutionized the manufacturing industry, offering a new paradigm to produce complex geometries and parts with customized properties. Among the different AM techniques, the wire arc additive manufacturing (WAAM) process has gained significant attention due to its high deposition rate and low equipment cost. However, the process is characterized by a complex thermal history making it challenging to simulate it in real-time for online process control and optimization. In this context, a reduced order model (ROM) using the proper generalized decomposition (PGD) method [1] is proposed as a powerful tool to overcome the limitations of conventional numerical methods and enable the real-time simulation of the temperature field of WAAM processes. These simulations use a moving heat source leading to a hardly separable parametric problem, which is handled by applying a novel mapping approach [2]. This procedure makes it possible to create a separated representation of the model, which is required to apply the PGD method, allowing a simulation of multiple layers. In this contribution, a PGD model is derived for the temperature field simulation of the WAAM process. A layer-by-layer simulation in combination with a compression of the PGD modes, without influencing the approximation error, is shown. The compression is an essential step since the modes sum up quickly over the layers and thus a reduction of the number of modes is needed. Furthermore, using an element birth technique leads usually to an update of the mesh or a new mesh in each time step. Though, this is not the case applying the mapping approach, where only a single nonchanging mesh is required to simulate the deposition of a whole layer. T2 - ECCOMAS Congress 2024 CY - Lisbon, Portugal DA - 03.06.2024 KW - Reduced Order Model KW - Proper Generalized Decomposition KW - Thermal transient problem KW - Additive manufacturing PY - 2024 AN - OPUS4-62231 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Gluth, Gregor ED - Wittke, W. T1 - Alkalisch aktivierter Beton (Geopolymer-Beton) N2 - Alkalisch aktivierte Bindemittel (AAB) sind Zemente, deren Erhärtung auf der alkalischen Anregung von reaktiven Aluminiumsilicaten beruht. AAB sind nach gegenwärtigem Stand die vielversprechendste Option, die mit der Herstellung und dem Einsatz von Zementen verbundenen CO2-Emissionen mittel- bis langfristig signifikant zu senken. Die Erhärtungsreaktionen und die Einflüsse auf die Mikrostruktur von AAB sind durch jahrzehntelange Forschung gut verstanden, und zahlreiche Beispiele belegen, dass AAB grundsätzlich als Betonbindemittel geeignet sind. Offene Fragen bestehen aber immer noch hinsichtlich der Dauerhaftigkeit von mit AAB hergestellten Betonen. Der vorliegende Beitrag gibt eine kurze Einführung in die Nomenklatur und die Geschichte von AAB. Die wichtigsten Reaktionen und Reaktionsprodukte, die zur Bildung der Mikrostruktur von AAB führen, werden beschrieben. Der Hauptteil des Beitrags diskutiert aktuelle Forschungsergebnisse und offene Fragen zur Dauerhaftigkeit von Betonen auf Basis von AAB. Wichtige Fortschritte auf diesem Gebiet konnten in den letzten Jahren insbesondere zum Einfluss von Sulfiden auf die Bewehrungskorrosion, zum Carbonatisierungswiderstand und zum Säurewiderstand erzielt werden. T2 - 10. Felsmechanik- und Tunnelbautag CY - Weinheim, Germany DA - 22.05.2025 KW - Alkali-activated materials KW - Carbonation KW - Reinforcement corrosion KW - MIC KW - Microbially induced corrosion PY - 2025 SN - 978-3-00-083562-9 SP - 73 EP - 84 PB - WBI GmbH CY - Weinheim AN - OPUS4-64266 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Simon, Patrick A1 - Baeßler, Matthias ED - Cunha, Álvaro ED - Caetano, Elsa T1 - On the reassessment of bridge superstructure vibrations for high-speed traffic N2 - The acceleration thresholds of bridge superstructures remain critical for designing and reassessing railway bridges on high-speed lines, with ballasted track systems historically limited to 3.5 m/s2 vertical accelerations due to destabilization risks. As part of the European InBridge4EU project, this study addresses methodological uncertainties in linking vertical bridge vibrations to lateral track creep—a key focus area for modernizing assessment protocols. A comparative analysis of two acceleration postprocessing methods (peak identification vs. fatigue-derived rainflow counting) as part of a recently proposed framework was conducted using an example bridge and train combination. Results demonstrate that rainflow counting yields more conservative creep estimates with the bulk of cumulative vibration-induced creep attributable to accelerations exceeding 3 m/s2. However, discretizing acceleration ranges into 1 m/s2 bins introduced significant errors compared to continuous cycle data, highlighting sensitivity to analysis parameters. These findings underscore the complexity of reconciling laboratory-derived harmonic vibration models with real-world bridge dynamics, where non-uniform acceleration patterns dominate. The research directly informs ongoing efforts to refine standardized criteria for ballasted track stability, particularly through the InBridge4EU project’s systematic re-evaluation of vibration limits and their engineering implications. By quantifying discrepancies between computational approaches, this work advances the development of robust protocols for predicting track degradation under high-speed operational loads. T2 - 11th International Conference on Experimental Vibration Analysis for Civil Enginering Structures (EVACES 2025) CY - Porto, Portugal DA - 02.07.2025 KW - Infrastructure KW - Railway bridges KW - Ballast destabilization KW - Acceleration limit KW - Ballasted track KW - Rainflow counting PY - 2025 DO - https://doi.org/10.1007/978-3-031-96106-9_53 SP - 506 EP - 515 PB - Springer CY - Cham AN - OPUS4-64267 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Baeßler, Matthias A1 - Simon, Patrick ED - Cunha, Álvaro ED - Caetano, Elsa T1 - Review of Ballasted Track Destabilization on Shake Table Tests N2 - Shake table tests have been used for a long time to understand the densification and fluidization of granular materials. While purely vertical shaking is quite unlikely to be found in vibration analysis when it comes to granular materials as soils, it has been found that the vertical vibration of railway bridge support structures can affect the fabric of the ballasted track on top. Starting from the experience at French railway lines with destabilizing track conditions on short bridges in high speed lines in the 1990s, various shake table test configurations have been used to investigate the destabiliza-tion of ballast at high acceleration levels. This article describes the effects of the variously investigated dynamic excitations of railway bridges on the bal-lasted track itself. T2 - 11th International Conference on Experimental Vibration Analysis for Civil Engineering Structures (EVACES 2025) CY - Porto, Portugal DA - 02.07.2025 KW - Infrastructure KW - Ballasted track KW - Ballast KW - Railway bridge dynamics PY - 2025 DO - https://doi.org/10.1007/978-3-031-96106-9_62 SP - 595 EP - 604 PB - Springer CY - Cham AN - OPUS4-64265 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Baeßler, Matthias T1 - On potentials and challenges of physics-informed SHM for civil engineering structures N2 - Physics-informed structural health monitoring, which incorporates realistic physical models of material behavior, structural response, damage mechanisms, and aging processes, offers a promising framework to enhance monitoring capabilities and inform operation and maintenance planning. Nevertheless, the technical challenges and model requirements associated with this approach are highly context-dependent and can vary significantly across different applications. The presentation focusses on two case studies that highlight challenges and progress in Physics informed SHM. T2 - SHMII-13 CY - Graz, Austria DA - 01.09.2025 KW - SHM KW - Physics informed KW - Hydrogen Stress Corrosion Cracking PY - 2025 AN - OPUS4-64326 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schönsee, Eric T1 - A framework for characterising the reflection intensity of a 3D-CP mortar N2 - The growing interest of 3D Concrete Printing (3DCP) arises new challenges for quality control. A major challenge lies in evaluation of the interlayer bond strength. An optical approach is developed to monitor the surface properties of the printed layer. Commercial laser profile scanners are utilised to record the reflection intensity of the mortar’s surface. To be applicable in the printing process, the reflection intensity needs to be characterised for each material within the printable region and further effects, like geometry and environmental light, need to be considered. The presented work aims to provide a framework for implementing the laser reflection intensity to 3DCP monitoring. T2 - NDT-CE 2025 - The International Symposium on Nondestructive Testing in Civil Engineering CY - Izmir, Türkiye DA - 24.09.2025 KW - 3D Concrete Printing KW - In Situ Measurements KW - Laser reflection intensity PY - 2025 AN - OPUS4-64305 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Krebs, N. A1 - Demleitner, M. A1 - Albuquerque, R.Q. A1 - Schartel, Bernhard A1 - Ruckdäschel, H. T1 - Bayesian Optimization of flame-retardant performance in a high-Tg epoxy resin system N2 - Polymeric materials are widely used due to their mechanical properties and cost-effectiveness, but their inherent flammability requires effective flame-retardant additives to meet safety standards. Optimizing multicomponent flame-retardant formulations is challenging due to the vast experimental space. This study applies Bayesian Optimization (BO) to optimize flame-retardant formulations in high glass transition temperature (Tg) epoxy resins. Aluminum diethyl phosphinate (AlPi) was systematically combined with three synergists: zinc stannate (ZnSt), a silicone-based additive (DowSil), and low-melting glass frits (Ceepree). BO-guided experimental design expanded from 16 initial formulations to a total of 28, minimizing the Maximum Average Rate of Heat Emission (MARHE) under the constraint of Total Smoke Production (TSP) < 17 m2 using the epsilon-constraint method. BO revealed non-linear synergistic interactions: ZnSt significantly reduced smoke production while AlPi effectively lowered heat release. The optimized formulation (BO7) achieved the lowest MARHE (122 kW/m2) while maintaining acceptable smoke levels, establishing a new Pareto front. The results demonstrate the effectiveness of BO in accelerating the development of synergistic, halogen-free flame-retardant polymer systems, offering a scalable and sustainable approach to polymer formulation design. KW - Machine learning KW - Epoxy resin KW - Bayesian optimization KW - Flame retardancy KW - Cone calorimeter PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-641070 DO - https://doi.org/10.1016/j.commatsci.2025.114210 SN - 0927-0256 SN - 1879-0801 VL - 260 SP - 1 EP - 9 PB - Elsevier AN - OPUS4-64107 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Strommer, Bettina T1 - Anisotropy in natural rubber / graphene nanocomposites N2 - The incorporation of nanoscale particles into elastomers enable a boost in performance and/or a distinct reduction of conventional filler loadings due to their high surface to volume ratio. 2D layered nanoparticles like graphene and graphene-related materials provide a great potential as effective fillers in rubber, especially by enhancing mechanical and barrier properties. The type and properties of the nanoparticles, their interface and the elastomeric matrix materials influence the technical behavior, and therefore the potential application fields of such rubber nanocomposites. Especially crucial for the efficiency of the nanofiller, however, is its best possible incorporation into the elastomer. The dispersing of nanoparticles without agglomerates usually constitutes a challenge when using conventional two-roll milling or internal mixing. Academic approaches for highly dispersed nanocomposites solve this problem but are often energy and time consuming with no feasible scale up possibility. Therefore, an ultrasonic assisted NR latex premixing process was established to produce highly filled masterbatches, enabling the main processing with conventional rubber processing techniques. Two carbon-based nanoparticles with similar specific surface areas were investigated and incorporated in natural rubber as nanocomposites: A commercially available multilayer graphene (MLG) and a nanoscale carbon black (nCB). The mentioned premixed masterbatches were further processed to nanocomposites by the addition of matrix NR, two-roll milling, and hot pressing (vulcanization). By this procedure an increase in Young’s modulus of 157% (MLG) and 71% (nCB) could be obtained at a concentration level of 3 phr. As anisotropic material behavior was observable for the nanocomposites containing MLG, different measurement methods were investigated to quantify the orientation of the nanoparticles in the nanocomposites: Sorption measurements (swelling in 2 dimensions), hardness and dynamical mechanical analysis (in-plane vs. cross-plane), X-Ray diffraction and transmission and scanning electron microscopy. T2 - DKT IRC 21 CY - Nuremberg, Germany DA - 27.06.2022 KW - Processing KW - Elastomers KW - Nanocomposites KW - Graphene KW - Orientation KW - Anisotropy PY - 2022 AN - OPUS4-55205 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bäßler, Ralph T1 - Metallene Werkstoffe in Geothermieanlagen - nicht nur aus Sicht der Korrosion N2 - Um Konstrukteuren und Nutzern geothermischer Anlagen grundlegende Informationen über die Korrosionsbeständigkeit zur Verfügung zu stellen, wurden verschiedene metallene Werkstoffe, darunter nichtrostende Duplex- und austenitische Stähle sowie eine Nickellegierung, in künstlichen Geothermalwässern, die die Bedingungen an verschiedenen Standorten mit geothermischem Potenzial simulieren, mit Hilfe von elektrochemischen und Langzeittests hinsichtlich ihrer Eignung bewertet. In hochsalinaren Umgebungen erwies sich Spaltkorrosion als der entscheidende Mechanismus. Die Nickellegierung zeigt eine ausgezeichnete Beständigkeit gegenüber Lochkorrosion. Abgesehen von ihren hohen Kosten eignet sie sich sehr gut für den Bau von Geothermieanlagen mit stark salzhaltigen Fluiden. Rostfreie Stähle und Duplexstähle weisen eine begrenzte Korrosionsbeständigkeit gegen Loch- und Spaltkorrosion auf. Daher sind sie für stark salzhaltige Fluide nicht geeignet. Der Superaustenit zeigt ein temperaturabhängiges Verhalten. In nichtsalinaren Umgebungen könnten niedriglegierte Stähle (neben den höherlegierten Werkstoffen) als Konstruktionsmaterial für Geothermieanlagen eingesetzt werden, sofern eine ausreichende Wandstärke des Materials berücksichtigt wird. Neben Korrosionsaspekten erwies sich auch die Ausfällung von Fluidbestandteilen als interessantes Thema. Beim Betrieb der Forschungsanlage in Groß Schönebeck wurden Kupfer- und Bleieffekte im Bohrloch festgestellt. Die auftretenden Mechanismen und Maßnahmen zur Verhinderung von Ausfällungen und Abscheidungen wurden ebenso untersucht, wie deren mögliche Einflüsse auf die Korrosionsbeständigkeit metallener Werkstoffe für Anlagenkomponenten. Der Beitrag beschreibt die Wechselwirkungen zwischen Geothermalwässern und Ausrüstungskomponenten. T2 - 57. Kraftwerktechnisches Kolloquium CY - Dresden, Germany DA - 07.10.2025 KW - Örtliche Korrosion KW - Edelstahl KW - Ni-Legierungen KW - Geothermie KW - Abscheidung PY - 2025 AN - OPUS4-64323 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Lehmann Schlag, Jens T1 - Aus Schäden wird man klug – Glänzende Aussichten für nichtrostende Stähle N2 - In diesem Beitrag werden Schadensbeispiele aus verschiedensten Branchenanwendungen nichtrostender Stähle gezeigt, die den Teilnehmern vor Augen führen sollen, an welchen Stellen Fehler zu Korrosionsschäden führen können. T2 - ISER - Kursleiterfortbildung 2025 CY - Götz, Germany DA - 22.09.2025 KW - Korrosion KW - Nichtrostender Stahl KW - KorroPad KW - Edelstahl rostfrei PY - 2025 AN - OPUS4-64285 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Jauregui Rozo, Maria A1 - Sunder, S. A1 - Tabaka, Weronika A1 - Klaffke, Benjamin A1 - Ruckdäschel, H. A1 - Schartel, Bernhard T1 - Unveiling aluminum diethyl phosphinate dual identity: Transfer from epoxy resins to glass fiber-reinforced composites N2 - This study examines the transfer of the flame-retardant aluminum diethyl phosphinate (AlPi) from epoxy resins to composites and the impact of AlPi on fire behavior and fire stability. Further, the effects of different particle sizes and the addition of zinc hydroxy stannate (ZHS) and inorganic silicate (InSi) are investigated. The research provides a detailed analysis of the fire behavior, fire stability, pyrolysis, flame-retardant modes of action, and flame retardancy index. Interestingly, the particle sizes did not significantly affect the flammability, fire behavior, or fire stability in the systems investigated. AlPi acts primarily in the gas phase, releasing phosphorus that yields flame inhibition. Adding glass fibers (GFs) to the epoxy resin boosts the flame retardancy in the condensed phase, reducing the heat release rate (HRR), total heat release (THR), and peak heat release rate (PHRR) by about 60%. This improvement is largely due to replacing fuel and forming a protective layer during burning. Despite the differences between thermoset and composite, the study demonstrates an effective transfer of flame-retardant properties from epoxy resins to fiber-reinforced composites, significantly enhancing the flame retardancy performance in both material systems. KW - Aluminum diethyl phosphinate KW - Epoxy resins KW - Fire behavior KW - Fire stability KW - Gas-phase active KW - Glass fiber-reinforced composites KW - Particle sizes PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-643013 DO - https://doi.org/10.1002/pc.29911 SN - 1548-0569 SN - 0272-8397 VL - 46 IS - 14 SP - 12981 EP - 12999 PB - Wiley AN - OPUS4-64301 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schönsee, Eric A1 - Hüsken, Götz A1 - Kocherla, Amarteja A1 - Strangfeld, Christoph T1 - A framework for characterising the reflection intensity of a 3D-CP mortar N2 - The growing interest of 3D Concrete Printing (3DCP) arises new challenges for quality control. A major challenge lies in evaluation of the interlayer bond strength. An optical approach is developed to monitor the surface properties of the printed layer. Commercial laser profile scanners are utilised to record the reflection intensity of the mortar’s surface. To be applicable in the printing process, the reflection intensity needs to be characterised for each material within the printable region and further effects, like geometry and environmental light, need to be considered. The presented work aims to provide a framework for implementing the laser reflection intensity to 3DCP monitoring. T2 - NDT-CE 2025 - The International Symposium on Nondestructive Testing in Civil Engineering CY - Izmir, Türkiye DA - 24.09.2025 KW - 3D Concrete Printing KW - In Situ Measurements KW - Laser reflection intensity PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-643047 DO - https://doi.org/10.58286/31728 SN - 1435-4934 SP - 1 EP - 4 PB - NDT.net AN - OPUS4-64304 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Karafiludis, Stephanos A1 - Standl, Jacob A1 - Ryll, Tom W. A1 - Schwab, Alexander A1 - Prinz, Carsten A1 - Wolf, Jakob B. A1 - Kruschwitz, Sabine A1 - Emmerling, Franziska A1 - Völker, Christoph A1 - Stawski, Tomasz M. T1 - High-Entropy Phosphate Synthesis: Advancements through Automation and Sequential Learning Optimization N2 - Transition metal phosphates (TMPs) are extensively explored for electrochemical and catalytical applications due to their structural versatility and chemical stability. Within this material class, novel high-entropy metal phosphates (HEMPs)─containing multiple transition metals combined into a single-phase structure─are particularly promising, as their compositional complexity can significantly enhance functional properties. However, the discovery of suitable HEMP compositions is hindered by the vast compositional design space and complex or very specific synthesis conditions. Here, we present a data-driven strategy combining automated wet-chemical synthesis with a Sequential Learning App for Materials Discovery (SLAMD) framework (Random Forest regression model) to efficiently explore and optimize HEMP compositions. Using a limited set of initial experiments, we identified multimetal compositions in a single-phase crystalline solid. The model successfully predicted a novel Co0.3Ni0.3Fe0.2Cd0.1Mn0.1 phosphate octahydrate phase, validated experimentally, demonstrating the effectiveness of the machine learning approach. This work highlights the potential of integrating automated synthesis platforms with data-driven algorithms to accelerate the discovery of high-entropy materials, offering an efficient design pathway to advanced functional materials. KW - Metal phosphates KW - High entropy KW - Sequential learning KW - Automated synthesis KW - MAP KW - Random forest KW - Machine learning PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-641554 DO - https://doi.org/10.1021/acs.cgd.5c00549 SN - 1528-7483 VL - 25 IS - 19 SP - 7989 EP - 8001 PB - American Chemical Society (ACS) CY - Washington, DC AN - OPUS4-64155 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schacht, Gregor A1 - Marx, Steffen A1 - Scheerer, Silke A1 - Fiedler, Max A1 - Ritter, Robert A1 - Clages, Luise A1 - Voigt, Chris A1 - Czeschka, David A1 - Ebell, Gino A1 - Marzahn, Gero T1 - Einsturz der Carolabrücke in Dresden Teil 2 T1 - Collapse of the Carola Bridge in Dresden Part 2 Investigations into the causes of the collapse and the consequences N2 - Am 11. September 2024 ereignete sich der Teileinsturz der vorgespannten Carolabrücke in Dresden ohne Vorankündigung. Im Teil 1 des Beitrags wurden Konstruktion und Bau der Brücke, die Maßnahmen zur Instandhaltung und Sanierung sowie die Problematik Spannungsrisskorrosion vorgestellt. Im vorliegenden Teil 2 werden die umfassenden Untersuchungen zur Erkundung der Einsturzursache beschrieben, der Versuch der Rekonstruktion des Einsturzvorgangs unternommen sowie erste Erkenntnisse zum weiteren Umgang mit anderen Brücken, die SpRK‐gefährdeten Stahl enthalten, dargelegt. Zudem wird auf das Monitoring eingegangen, welches zur Absicherung der verbliebenen Überbauzüge vorgesehen wurde, und ein Ausblick auf die Herausforderungen beim Rückbau gegeben. KW - Korrosion KW - Spannungsrisskorrosion KW - Wasserstoffversprödung PY - 2025 DO - https://doi.org/10.1002/best.70008 SN - 0005-9900 SP - 1 EP - 10 PB - Ernst & Sohn GmbH AN - OPUS4-64005 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Koniorczyk, M. A1 - Bednarska, Dalia A1 - Wieczorek, A. A1 - Materak, K. T1 - Probabilistic approach to concrete durability based on combined stochastic differential equations and Monte Carlo method N2 - Cementitious materials are often exposed to aggressive environments, which have a significant impact on their durability. Proper prediction of concrete corrosion helps to apply the right measures and technologies, to extend the service life of structures. Carbonation and cyclic freezing are recognized among the most common corrosive factors for concrete. Their progress is linked to the penetration of CO2 and water into the concrete structure. Due to the random arrangement of aggregates and cement paste, concrete is an inhomogeneous material. Therefore, the progress of carbonation and frost-induced damage should be treated as random variables with appropriate probabilistic parameters. Experimental studies on concrete carbonation and freezing were conducted in accordance with the standards EN 12390–12 and EN 12390–9. As observed in the experiments, the progress of carbonation and frost damage of concrete could be described by zigzag, not necessarily monotonic functions. Stochastic differential equations (SDE) were employed to predict the behavior of concrete exposed to elevated CO2 concentrations and cyclic freezing. The stochastic model consisted of a drift term, which described the general trend of concrete durability exposed to carbonation and frost cycles, as well as a diffusion term, which accounted for the stochastic features of inhomogeneous concrete microstructure. The Euler–Maruyama approximation with Milstein improvement was applied to model the realization of the stochastic changes in concrete microstructure/durability. The proposed approach predicted experimental results with high accuracy. The application of the Monte Carlo (MC) method with 100,000 SDE realizations allowed to calculate the statistical parameters of the processes, such as concrete carbonation and freezing cycles. The probabilistic parameters, such as expected values and standard deviations, calculated using the SDE_MC approach, were in good agreement with experimental results for both problems, i.e. decelerating concrete carbonation and accelerating concrete scaling. KW - Concrete durability KW - Concrete carbonation KW - Concrete scaling KW - Time-dependent random variable KW - Stochastic differential equations PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-643417 DO - https://doi.org/10.1007/s43452-025-01335-y SN - 2083-3318 VL - 25 IS - 5-6 SP - 1 EP - 31 PB - Springer Nature Switzerland AG CY - Schweiz AN - OPUS4-64341 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Chacon Castro, Jose P. A1 - Schartel, Bernhard T1 - Translating Flame Retardant Strategies: Analogy from Polyolefins and Bisphenol A polycarbonates to Poly(limonene carbonate) N2 - Poly(limonene carbonate)—PLimC—offers a novel sustainable alternative to traditional polymers, as it is derived from renewable limonene and carbon dioxide as monomers. Proposing PLimC as a future technical polymer for applications in electrical and electronic (E&E) devices, construction, and transportation, PLimC must meet specific fire prevention standards to be deemed suitable. Starting from the chemical structure of PLimC, strategies in analogy to flame retarded bisphenol A polycarbonates (PC), PC blends, and polyolefins (PO) are investigated to identify the most effective route to enhance the flame resistance of PLimC. This study utilized four halogen-free flame-retardant (FR) systems: APP + pentaerythritol (standard intumescent system in PO), a phosphorus flame retardant+PTFE as anti-dripping agent (used in PC blends), metal hydroxide ATH (widely used in PO), and potassium sulfonate salt (specific solution for PC). Applying these FRs at typical PC, PC blends, and PO loadings, we aim to understand their effect on PLimC and evaluated the different flame-retardant routes. Our experimental evaluations focused on the thermal properties, flammability, and fire behavior of each system. ATH emerged as the most effective, reducing the effective heat of combustion from 29.3 MJ kg⁻¹ to 18.6 MJ kg⁻¹ and the total heat evolved from 95 to 55 MJ m⁻². It also resulted in an increase in the limiting oxygen index from 17.1 to 26 vol.-% O2, along with a UL 94 HB40 rating. The intumescent system also exhibited considerable flame retardancy, highlighting the similarity of PLimC’s fire behavior to that of PO rather than PC KW - Poly(limonene carbonate) KW - Flame retardancy KW - Sustainability KW - Intumescent systems KW - Metal hydroxides KW - Sulfonate salts KW - Phosphorus flame retardants PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-643257 DO - https://doi.org/10.1016/j.polymdegradstab.2025.111711 SN - 1873-2321 SN - 0141-3910 VL - 242 SP - 1 EP - 18 PB - Elsevier Ltd. AN - OPUS4-64325 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bäßler, Ralph A1 - Keserović, A. A1 - Sobetzki, J. A1 - Sarmiento-Klapper, H. A1 - Boduch, A. A1 - Aristia, G. A1 - Faes, W. A1 - Stoljarova, A. A1 - Zimmer, S. T1 - Metallene Werkstoffe in Geothermieanlagen - nicht nur aus Sicht der Korrosion N2 - Um Konstrukteuren und Nutzern geothermischer Anlagen grundlegende Informationen über die Korrosionsbeständigkeit zur Verfügung zu stellen, wurden verschiedene metallene Werkstoffe, darunter nichtrostende Duplex- und austenitische Stähle sowie eine Nickellegierung, in künstlichen Geothermalwässern, die die Bedingungen an verschiedenen Standorten mit geothermischem Potenzial simulieren, mit Hilfe von elektrochemischen und Langzeittests hinsichtlich ihrer Eignung bewertet. In hochsalinaren Umgebungen erwies sich Spaltkorrosion als der entscheidende Mechanismus. Die Nickellegierung zeigt eine ausgezeichnete Beständigkeit gegenüber Lochkorrosion. Abgesehen von ihren hohen Kosten eignet sie sich sehr gut für den Bau von Geothermieanlagen mit stark salzhaltigen Fluiden. Rostfreie Stähle und Duplexstähle weisen eine begrenzte Korrosionsbeständigkeit gegen Loch- und Spaltkorrosion auf. Daher sind sie für stark salzhaltige Fluide nicht geeignet. Der Superaustenit zeigt ein temperaturabhängiges Verhalten. In nichtsalinaren Umgebungen könnten niedriglegierte Stähle (neben den höherlegierten Werkstoffen) als Konstruktionsmaterial für Geothermieanlagen eingesetzt werden, sofern eine ausreichende Wandstärke des Materials berücksichtigt wird. Neben Korrosionsaspekten erwies sich auch die Ausfällung von Fluidbestandteilen als interessantes Thema. Beim Betrieb der Forschungsanlage in Groß Schönebeck wurden Kupfer- und Bleieffekte im Bohrloch festgestellt. Die auftretenden Mechanismen und Maßnahmen zur Verhinderung von Ausfällungen und Abscheidungen wurden ebenso untersucht, wie deren mögliche Einflüsse auf die Korrosionsbeständigkeit metallener Werkstoffe für Anlagenkomponenten. Der Beitrag beschreibt die Wechselwirkungen zwischen Geothermalwässern und Ausrüstungskomponenten. T2 - 57. Kraftwerktechnisches Kolloquium CY - Dresden, Germany DA - 07.10.2025 KW - Örtliche Korrosion KW - Edelstahl KW - Ni-Legierungen KW - Geothermie KW - Abscheidung PY - 2025 SN - 978-3-00-082651-1 SN - 978-3-00-082652-8 SP - 551 EP - 568 PB - IKS-Verlag CY - Freiberg AN - OPUS4-64320 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Baeßler, Matthias A1 - Ebell, Gino A1 - Herrmann, Ralf A1 - Hille, Falk A1 - Schneider, Ronald ED - Lienhart, Werner ED - Krüger, Markus T1 - On potentials and challenges of physics-informed SHM for civil engineering structures N2 - Physics-informed structural health monitoring, which integrates realistic physical models of material behavior, structural response, damage mechanisms, and aging processes, offers a promising approach to improve monitoring capabilities and inform operation and maintenance planning. However, the associated technical challenges and model requirements are context-specific and vary widely across applications. To illustrate the relevance and potential of the topic, two application examples are presented. The first focuses on monitoring the modal characteristics of a prestressed road bridge, where strong sensitivity to temperature variations limits the diagnostic capabilities of conventional vibration-based global monitoring. The discussion highlights how environmental influences can obscure structural changes, and emphasizes that purely data-based approaches are inherently limited to detecting anomalies and do not enable comprehensive condition diagnostics. The second example explores a physics-informed monitoring approach for prestressed concrete bridges affected by hydrogen-induced stress corrosion cracking. T2 - SHMII-13 CY - Graz, Austria DA - 01.09.2025 KW - Hydrogen Stress Corrosion Cracking KW - SHM KW - Physics informed PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-643271 SN - 978-3-99161-057-1 DO - https://doi.org/10.3217/978-3-99161-057-1-039 SP - 245 EP - 251 PB - Verlag der Technischen Universität Graz CY - Graz, Austria AN - OPUS4-64327 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Baier, Johanna A1 - Wiehle, Philipp A1 - Thiele, Marc ED - Nille-Hauf, Konstantin T1 - Structural Design of Rammed Earth – Influence of Manufacturing Parameters on the Compressive Strength N2 - At present, no structural design code for rammed earth exists that is based on the semiprobabilistic safety concept and adequately reflects the mechanical performance of modern rammed earth structures. This research aims to establish a scientifically grounded design framework for load-bearing rammed earth walls, incorporating the semi-probabilistic safety approach to ensure reliability and structural integrity. As a first step within the research project the influence of the manufacturing parameters of rammed earth on its mechanical properties are investigated. Compressive strength tests are carried out on cylinders produced with varying initial moisture contents and different compaction energies. Moreover, it is investigated whether the Proctor test according to DIN 18127 [1] is suitable for determining the optimal moisture content (OMC) of rammed earth production. T2 - Earth Builder Summit EBS 2025 CY - Biberach, Germany DA - 06.03.2025 KW - Rammed earth KW - Structral design KW - Mechanical parameters PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:bsz:1033-opus-9812 DO - https://doi.org/10.60663/HFTor-981 SP - 41 EP - 44 PB - Hochschule Biberach AN - OPUS4-64343 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Unger, Jörg F. T1 - Development of a platform for benchmarking of simulation models for verification and validation N2 - This presentation introduces a modular and open platform developed by BAM for the verification and validation (V&V) of simulation models, particularly material models used across various solvers. The platform aims to enhance transparency, reproducibility, and comparability in computational engineering by integrating standardized workflows, benchmark datasets, and semantic technologies. Key components include: Simulation workflows powered by tools like Snakemake and JupyterHub, Research Object Crates (ROCrates) for structured data and provenance tracking, Ontologies and knowledge graphs to semantically describe models, data, and results, Federated registries for storing and querying benchmark results and ROCrates. The platform supports both verification (e.g., analytical comparisons, convergence studies) and validation (e.g., experimental data matching), and facilitates tool-independent performance metrics using standardized output formats. It promotes collaborative development through containerized environments, automated testing, and reproducible research practices. This initiative contributes to the broader goal of ensuring safety in technology and chemistry, aligning with BAM’s mission and supporting the scientific community in developing reliable simulation models. T2 - FABER Project CY - Prague, Czech Republic DA - 18.09.2025 KW - Verification and validation KW - Simulation Workflows KW - Digital Twin KW - Model Calibration PY - 2025 AN - OPUS4-64352 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Saif-Ur-Rehman, Saif-Ur-Rehman T1 - Assessing Structural Failure in Extrusion-based 3D Concrete Printing Using Plasticity Models N2 - 3D concrete printing (3DCP) brings automation in construction, reduces material usage, increases design flexibility, and eliminates the need for formwork. However, it is a complex process involving various parameters that are often defined by trial and error. This can lead to unforeseen failures during the print, such as buckling or yielding. Computational modeling can be used in the design stage to predict and prevent failure, during printing for real-time process control, and afterwards to assess how variations during printing affect the final structure. The structural failure during the print is primarily governed by how concrete behaves at the material level, making the choice of constitutive model crucial. Plasticity models are commonly used to assess buildability, with the Mohr-Coulomb criterion being a widely used approach [1]. However, its suitability for modeling fresh concrete for 3DCP, under such loading conditions and varying material properties is still an open research question. Furthermore, experimental studies have shown that fresh concrete exhibits non-linear behavior before failure [2], which is usually not considered in structural simulations of 3DCP. This work investigates the influence of plasticity models on different structural failure modes observed in 3DCP, specifically elastic buckling and plastic collapse. The non-linear behavior of fresh concrete is accounted for by incorporating non-linear isotropic hardening into the plasticity models. A Von-Mises plasticity model and a Mohr-Coulomb model with a hyperbolic smooth approximation are implemented, both incorporating non-linear hardening. An objective stress rate formulation is adopted to consider geometric non-linearity for accurate buckling predictions. As freshly deposited layers structurate over time, an age-dependent model is implemented to capture the stiffness and strength evolution of printed layers. To simulate the layer-by-layer process, a pseudo-density-based activation method is used, allowing sequential activation of layers as printing progresses. Model parameters are identified for different ages using Bayesian inference via inverse finite element modeling by numerically replicating stress-strain data from uniaxial compression tests on samples at different ages. Printing simulations are conducted for thin-walled and cylindrical structures, demonstrating the influence of choice of plasticity model on buckling behavior and material failure. T2 - The Fifth International Conference on Simulation for Additive Manufacturing (SIM-AM 2025) CY - Pavia, Italy DA - 9.09.2025 KW - 3D Concrete Printing KW - Material Modeling KW - Plasticity KW - Simulation PY - 2025 AN - OPUS4-64361 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Saif-Ur-Rehman, Saif-Ur-Rehman T1 - Assessing Structural Failure in Extrusion-based 3D Concrete Printing Using Plasticity Models N2 - 3D concrete printing (3DCP) brings automation in construction, reduces material usage, increases design flexibility, and eliminates the need for formwork. However, it is a complex process involving various parameters that are often defined by trial and error. This can lead to unforeseen failures during the print, such as buckling or yielding. Computational modeling can be used in the design stage to predict and prevent failure, during printing for real-time process control, and afterwards to assess how variations during printing affect the final structure. The structural failure during the print is primarily governed by how concrete behaves at the material level, making the choice of constitutive model crucial. Plasticity models are commonly used to assess buildability, with the Mohr-Coulomb criterion being a widely used approach. However, its suitability for modeling fresh concrete for 3DCP, under such loading conditions and varying material properties is still an open research question. Furthermore, experimental studies have shown that fresh concrete exhibits non-linear behavior before failure, which is usually not considered in structural simulations of 3DCP. This work investigates the influence of plasticity models on different structural failure modes observed in 3DCP, specifically elastic buckling and plastic collapse. The non-linear behavior of fresh concrete is accounted for by incorporating non-linear isotropic hardening into the plasticity models. A Von-Mises plasticity model and a Mohr-Coulomb model with a hyperbolic smooth approximation are implemented, both incorporating non-linear hardening. An objective stress rate formulation is adopted to consider geometric non-linearity for accurate buckling predictions. As freshly deposited layers structurate over time, an age-dependent model is implemented to capture the stiffness and strength evolution of printed layers. To simulate the layer-by-layer process, a pseudo-density-based activation method is used, allowing sequential activation of layers as printing progresses. Model parameters are identified for different ages using Bayesian inference via inverse finite element modeling by numerically replicating stress-strain data from uniaxial compression tests on samples at different ages. Printing simulations are conducted for thin-walled and cylindrical structures, demonstrating the influence of choice of plasticity model on buckling behavior and material failure T2 - 11th GACM Colloquium on Computational Mechanics 2025 CY - Braunschweig, Germany DA - 21.09.2025 KW - 3D concrete printing KW - Von-Mises plasticity KW - Mohr-Coulomb plasticity KW - Constitutive modeling KW - Non-linear hardening KW - Objective stress rate KW - Finite element modeling KW - Bayesian inference PY - 2025 AN - OPUS4-64360 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Andrés Arcones, Daniel T1 - Embedding model form uncertainties for Bayesian inference of discrepant simulations N2 - Simulation models are widely used to generate valuable insights into complex physical systems. To accurately reflect system behavior, these models require updates to their governing parameters based on system measurements. Bayesian inference methodologies are particularly attractive for this purpose, as they quantify parameter uncertainty. However, simulation models inherently exhibit discrepancies with observed measurements, as they cannot perfectly replicate the infinitely complex reality. Ignoring these discrepancies leads to overconfident estimations of the inferred posterior distributions, potentially centering around incorrect parameters. This issue affects the calculation of predictions and Quantities of Interest (QoIs), resulting in overly concentrated posterior distributions. The most common framework for incorporating model form uncertainty was developed by Kennedy and O’Hagan, which introduces a flexible discrepancy term that is inferred alongside model parameters. However, this approach does not preserve the physicality of the predictions nor facilitate the propagation of model form uncertainty to other QoIs. To address these limitations, Sargsyan proposed embedding the discrepancy term in the parameter formulation as a stochastic extension. This work demonstrates our own explainable framework for embedding model form uncertainties in the Bayesian system of complex engineering systems. Our framework emphasizes the interpretability of discrepancy terms, quantifies uncertainties for models with significant discrepancies relative to measurements and high noise levels, and fully propagates these uncertainties to QoIs for reliable statistical analysis. We apply this framework to a thermal compensation model for the structural health monitoring system of a bridge, illustrating its potential for enhancing decision-making in engineering applications. T2 - UNCECOMP 2025 CY - Rhodes, Greece DA - 15.06.2025 KW - Unsicherheiten Quantifizierung KW - Brückenüberwachung KW - Digitaler Zwilling PY - 2025 AN - OPUS4-64353 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Lehmann, Frank A. A1 - Hille, Falk A1 - Glisic, Branco ED - Lienhart, Werner ED - Krüger, Markus T1 - Global Perspectives on Structural Monitoring in Civil Engineering N2 - Structural Monitoring (SM) is crucial in civil engineering for ensuring the safety, functionality, and longevity of civil infrastructure, especially bridges. As its importance grows, SM practices are guided mainly by national standards, leading to fragmented approaches and limited global integration. This paper examines SM guidelines, focusing on contributions from Germany, while exploring the broader international framework. In Germany, key guidelines such as the DGZfP Merkblatt B09 and others offer structured methods and practice examples for long-term monitoring and performance assessment. Internationally, countries have developed their own SM frameworks. Amongst others, Austria’s RVS Richtlinie 13.03.01, France’s COFREND Livre Blanc, Canada’s ISIS Guidelines, the ACI Report 444.2-21 from the USA, the TRB Circular E-C246 and the CIRIA Guideline from the UK contribute to a global understanding of SM. These guidelines address common technical, theoretical, and economic challenges across regions. This paper highlights the need for international collaboration, identifying synergies and gaps to promote a unified approach to SM. It offers insights into global standards and how successful strategies can foster innovation and cohesion in SM practices worldwide. T2 - 13th International Conference on Structural Health Monitoring of Intelligent Infrastructure CY - Graz, Austria DA - 01.09.2025 KW - Structural Health Monitoring KW - bridge structures KW - guidelines PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-643859 DO - https://doi.org/10.3217/978-3-99161-057-1-063 SP - 411 EP - 419 PB - Verlag der Technischen Universität Graz AN - OPUS4-64385 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hille, Falk A1 - Wedel, Frederik A1 - Lehmann, Frank A. A1 - Pirskawetz, Stephan ED - Lienhart, Werner ED - Krüger, Markus T1 - Structural health monitoring guidelines for bridges in Germany N2 - With the advancement of digitalization and related technological developments, Structural Health Monitoring (SHM) has become a useful and increasingly widespread tool to assist in the maintenance management of bridges and other engineering structures. The process of implementing monitoring requires expertise in many fields such as civil engineering, bridge operation and maintenance, monitoring technology, and data analysis. In recent years, monitoring has moved from method and technology development to standard practice. However, the implementation of monitoring as a standardized process can be an obstacle, especially for bridge operators, due to a lack of practical experience combined with the various expertise required. This can affect several areas, such as determining the cost-effectiveness of a monitoring measure, proper tendering and contracting, quality control, analysis and evaluation of measurement data, and last but not least, data management. In order to support the introduction of monitoring technologies into the practice of infrastructure operators, several guidelines have been developed in Germany in recent years by different interest groups, each with a different focus and essentially complementing each other. This paper aims to provide an overview of four different recently published guidelines and to highlight their strengths and advantages. T2 - 13th International Conference on Structural Health Monitoring of Intelligent Infrastructure CY - Graz, Austria DA - 01.09.2025 KW - Structural Health Monitoring KW - Bridge structures KW - Guidelines PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-643809 DO - https://doi.org/10.3217/978-3-99161-057-1-064 SP - 420 EP - 427 PB - Verlag der Technischen Universität Graz AN - OPUS4-64380 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hille, Falk T1 - Structural health monitoring guidelines for bridges in Germany N2 - With the advancement of digitalization and related technological developments, Structural Health Monitoring (SHM) has become a useful and increasingly widespread tool to assist in the maintenance management of bridges and other engineering structures. The process of implementing monitoring requires expertise in many fields such as civil engineering, bridge operation and maintenance, monitoring technology, and data analysis. In recent years, monitoring has moved from method and technology development to standard practice. However, the implementation of monitoring as a standardized process can be an obstacle, especially for bridge operators, due to a lack of practical experience combined with the various expertise required. This can affect several areas, such as determining the cost-effectiveness of a monitoring measure, proper tendering and contracting, quality control, analysis and evaluation of measurement data, and last but not least, data management. In order to support the introduction of monitoring technologies into the practice of infrastructure operators, several guidelines have been developed in Germany in recent years by different interest groups, each with a different focus and essentially complementing each other. This paper aims to provide an overview of four different recently published guidelines and to highlight their strengths and advantages. T2 - 13th International Conference on Structural Health Monitoring of Intelligent Infrastructure CY - Graz, Austria DA - 01.09.2025 KW - Structural Health Monitoring KW - Bridge structures KW - Guidelines PY - 2025 AN - OPUS4-64384 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Sunder, S. A1 - Jauregui Rozo, Maria A1 - Deshpande, H. A1 - Neyer, A. A1 - Papaiya, V. A1 - Meinel, Dietmar A1 - Schartel, Bernhard A1 - Ruckdäschel, H. T1 - Char to the Rescue: Processing and Transfer of Flame-Retardant Epoxy Resins, Adjusting the Fire Behavior and Post-Fire Structural Integrity of Glass Fiber Composites N2 - Epoxy (EP) glass fiber reinforced composites (GFRCs) are extensively used in structural applications due to their excellent thermal and mechanical properties, but their inherent flammability limits fire-safe deployment. While numerous studies examine the flame retardancy of resins or individual composite systems, comprehensive studies evaluating simultaneous improvements in flame retardancy and post-fire mechanical integrity, specifically through prepreg processing, remain challenging. This study investigates the effectiveness and transferability of phosphorus-based flame retardant (FR) systems to diglycidyl ether of bisphenol A (DGEBA) and EP novolac resin matrices and their corresponding bidirectional glass fiber composites via prepregs. The FRs are chosen based on varying modes of action: ammonium polyphosphate with inorganic silicate (APP/InSi) primarily acts in the condensed phase (CP), and aluminum diethyl phosphinate with zinc hydroxystannate (AldietPO2/ZHS) is known to demonstrate both gas-phase (GP) and CP activity. Fire residues are tailored to compensate for structural defects from fire exposure. EP novolac, with higher aromaticity and cross-linking, possesses better inherent flame resistance compared to DGEBA. The novolac composites containing AldietPO2/ZHS simultaneously showed the highest retention of flexural properties after fire exposure and the best fire safety index. The experimental values of the post-fire flexural properties in the composites calibrated damage parameters in two theoretical models. KW - Composites KW - DGEBA KW - Epoxy novolac KW - Post-fire KW - Prepregs PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-643752 DO - https://doi.org/10.1002/pol.20250692 SN - 2642-4169 SN - 2642-4150 VL - 63 IS - 20 SP - 4295 EP - 4309 PB - Wiley AN - OPUS4-64375 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Rockel, Daniel A1 - Sanchez Olivares, G. A1 - Calderas, F. A1 - Schartel, Bernhard T1 - Two heads are better than one: Aluminum trihydroxide / phosphorous flame retardant combination in natural waste fiber biocomposites N2 - Future polymeric materials that replace fossil fuel-based engineering plastics demand the use of renewable sources as well as the implementation of key properties such as flame retardancy, processing, and mechanical properties. This study focuses on the combination of aluminum trihydroxide (ATH) and phosphorus-based flame retardants in compositable thermoplastic starch reinforced with sustainable multifunctional leather waste fibers. The flame retardants engender different flame-retardant modes of action, improving overall performance when combined. The partial substitution of ATH with phosphorous flame retardant allowed a reduction in flame retardant loading. Materials with 90 phr of ATH reached a limiting oxygen index of 31.5 vol.-% and a UL-94 rating of V-1, whereas the combination of 73 phr ATH and 7 phr of diphenyl ocytyl phosphate achieved a V-0 rating and a slightly reduced peak of heat release rate. This study demonstrates the potential of multicomponent systems implementing waste fiber–reinforced biocomposites. KW - Biocomposites KW - Flame retardancy KW - Phosphorous flame retardants KW - Synergism KW - Sustainability PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-639084 DO - https://doi.org/10.1016/j.polymertesting.2025.108938 SN - 0142-9418 SN - 1873-2348 VL - 150 SP - 1 EP - 17 PB - Elsevier Ltd. AN - OPUS4-63908 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Müller, Thoralf A1 - Beck, Matthias A1 - Gümmer, Klaas A1 - Tomandl, Alexander A1 - Ebell, Gino A1 - Angst, Ueli T1 - Aktueller Sachstand zum Thema Korrosionsschutz im konstruktiven Holzbau N2 - Dieser Beitrag behandelt die Anforderungen an den Korrosionsschutz metallener Verbindungsmittel im konstruktiven Holzbau. Die Wahl des Korrosionsschutzes spielt eine entscheidende Rolle für Dauerhaftigkeit und Sicherheit. Die Korrosionsbeständigkeit wird durch holzspezifische Eigenschaften, Holzfeuchte, chemische Bestandteile und atmosphärische Bedingungen beeinflusst. Daher ist eine korrosionsschutzgerechte Werkstoffauswahl unter Berücksichtigung dieser Parameter notwendig. Historisch durch Normen wie DIN 1052 und deren Weiterentwicklungen (z. B. DIN SPEC 1052-100) geprägt, definiert der zukünftige Eurocode 5 (DIN EN 1995-1-1) Mindestanforderungen an Verbindungsmittel und deren Korrosionsschutzmaßnahmen in Bezug auf die zu erwartenden Belastungen. Trotz bestehender und kommender Normen zeigen sich in der Praxis häufig Lücken und Unsicherheiten, was den Bedarf an klaren Leitlinien und praxisnahen Lösungen unterstreicht. Fortschritte in der Beschichtungstechnologie und die Entwicklung standardisierter Prüfmethoden bieten vielversprechende Ansätze und Werkzeuge zur Verbesserung der Dauerhaftigkeit. Das Dokument betont die Bedeutung normativer Anpassungen in den kommenden Eurocodes sowie die Rolle von Forschung und Innovation, um die ökologischen und technischen Potenziale des Holzbaus besser zu nutzen und dessen Einsatz in der modernen Architektur zu fördern. KW - Holzbau KW - Korrosionsschutz KW - Verbindungsmittel KW - Eurocode 5 KW - DIN SPEC 1052-100 PY - 2025 DO - https://doi.org/10.1002/bate.70036 SN - 0932-8351 SP - 1 EP - 9 PB - Ernst & Sohn GmbH CY - Berlin AN - OPUS4-64405 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hille, Falk T1 - System identification and model calibration of a steel road bridge N2 - Steel box girder bridges with orthotropic deck plates are typically subject to traffic induced fatigue. Prognosis of fatigue is based on structural and traffic load models. Structural models can be updated based on measured response data. This contribution presents operational modal analysis and FE model calibration of a large steel box girder bridge. The identified modal properties show good conformity with the numerical model in frequencies and mode shapes. Model calibration by optimization leads to improved agreement but lacks robustness. Calibrated models are useful for increasing the value of information of monitoring measures, especially regarding digital twins. T2 - 11th International Operational Modal Analysis Conference (IOMAC 2025) CY - Rennes, France DA - 20.05.2025 KW - Steel bridge KW - Operational modal analysis KW - Model calibration PY - 2025 AN - OPUS4-64418 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Zinas, Orestis T1 - A Modular Gaussian Process Regression Toolbox for Uncertainty Aware Geotechnical Site Characterization N2 - A modular Gaussian Process Regression toolbox for efficient large-scale geotechnical site characterization from sparse 1D data was presented at the Third Future of Machine Learning in Geotechnics (3FOMLIG), Florence, Italy, October 16, 2025. The PyTorch/GPyTorch-based framework enables multivariate modeling of correlated soil properties and joint regression-classification of continuous CPT parameters with categorical soil units through Dirichlet transformations. Stochastic Variational Inference reduces computational complexity from O(N³) to O(M³), enabling GPU-accelerated processing of 100,000+ measurements. Validated on a 33 km² North Sea offshore wind farm site with 100+ sparse investigation points, the toolbox generates uncertainty-aware 3D predictions, supporting univariate, multivariate (LMC), and sequential multi-group modeling strategies. T2 - Third Future of Machine Learning in Geotechnics (3FOMLIG) CY - Florence, Italy DA - 15.10.2025 KW - Probabilistic site-characterization KW - Gaussian process regression KW - Bayesian inference KW - Offshore Wind Farms PY - 2025 AN - OPUS4-64423 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hille, Falk A1 - Schneider, Ronald A1 - Simon, Patrick A1 - Herrmann, Ralf A1 - Baeßler, Matthias ED - Döhler, Michael ED - Mélot, Adrien ED - Aenlle Lopez, Manuel T1 - System identification and model calibration of a steel road bridge N2 - The Bundesanstalt für Materialforschung und -prüfung (BAM), in cooperation with the Netherlands Organization for Applied Scientific Research (TNO), is working on a framework for integrating frequently updated structural models into an asset management process for bridge structures. A multi-span steel road bridge was selected as a test case for the development of this framework. In order for the structural model to represent the real behavior of the bridge with sufficient accuracy, model calibration is required. In this case, we have planned to calibrate the model based on the dynamic response of the bridge. To determine its dynamic properties, a multi-setup operational modal analysis was performed on one of the bridge spans. In parallel, a structural model of the span was developed based on the available design and service life information. Both eigenfrequencies and mode shapes were used as reference parameters to calibrate the model. A sensitivity analysis was performed to identify the most influential design parameters. Subsequently, a genetic algorithm was applied for minimizing the difference between measured and simulated characteristic responses. In the proposed paper, we summarize the measurements as well as the determination of the modal response of the bridge and describe the process of calibration of the structural model using the identified dynamic response. T2 - 11th International Operational Modal Analysis Conference (IOMAC 2025) CY - Rennes, France DA - 20.05.2025 KW - Bridge structure KW - Operational modal analysis KW - Model calibration PY - 2025 SN - 978-84-09-75120-4 SP - 114 EP - 121 PB - International Group of Operational Modal Analysis CY - Gijón, Spain AN - OPUS4-64416 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Müller, Thoralf A1 - Lehmann Schlag, Jens T1 - Korrosionsverhalten nichtrostender Stähle und Prüfverfahren N2 - Der Vortrag behandelt die wesentlichen Einflussfaktoren auf die Korrosionsbeständigkeit rostfreier Stähle sowie gängige und neue Prüfmethoden zur Bewertung ihrer Widerstandsfähigkeit. Im Fokus stehen die Zusammenhänge zwischen Werkstoff, Verarbeitung, Medium und Konstruktion, insbesondere die Auswirkungen von Kalt- und Warmumformung, Schweißprozessen und Oberflächenbehandlungen wie Beizen oder Elektropolieren auf die Passivschichtbildung. Verschiedene Korrosionsarten – darunter Loch-, Spalt-, interkristalline und Spannungsrisskorrosion – werden hinsichtlich ihrer Entstehungsmechanismen und Prüfmethoden erläutert. Abschließend wird mit dem KorroPad®-Verfahren ein praxisnahes, schnelles Prüfverfahren vorgestellt, das die lokale Anfälligkeit von Oberflächen gegenüber Lochkorrosion sichtbar macht und zur Optimierung von Fertigungs- und Nachbearbeitungsprozessen dient. T2 - Inhouse Seminar "Korrosionsverhalten nichtrostender Stähle" CY - Ravensburg, Germany DA - 15.10.2025 KW - Korrosion KW - Nichtrostende Stähle KW - KorroPad KW - Passivität KW - DIN 50024 PY - 2025 AN - OPUS4-64445 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Lehmann Schlag, Jens A1 - Müller, Thoralf T1 - Korrosionsschutzgerechte Werkstoffauswahl nichtrostender Stähle N2 - Der Vortrag behandelt die systematische Auswahl nichtrostender Stähle unter Berücksichtigung mechanischer, chemischer und wirtschaftlicher Kriterien. Im Mittelpunkt steht das Zusammenspiel von Werkstoff, Medium und Umgebung, das die Korrosionsbeständigkeit als Systemeigenschaft bestimmt. Anhand von Kennzahlen wie Wirksumme, PRE(N) oder MARC wird die legierungsabhängige Beständigkeit gegenüber Loch- und Spaltkorrosion bewertet. Ergänzend werden Einflüsse wie Schwefelgehalt und Zerspanungsgüten auf das Korrosionsverhalten dargestellt. Der Vortrag zeigt praxisorientierte Hilfsmittel zur Werkstoffauswahl – darunter DECHEMA-Werkstofftabellen, ThyssenKrupp-Beständigkeitslisten und normative Vorgaben wie DIN EN 1993-1-4. Zudem werden typische Fehler bei der Werkstoffbestellung und -kennzeichnung erläutert und praxisnahe Empfehlungen gegeben, um korrosionsbedingte Schäden, etwa im Bauwesen oder bei Tunnelinstallationen, zu vermeiden. T2 - Inhouse Seminar "Korrosionsverhalten nichtrostender Stähle" CY - Ravensburg, Germany DA - 15.10.2025 KW - Korrosion KW - Nichtrostende Stähle KW - Werkstoffauswahl KW - Eurocode 3 KW - Korrosionsschutz PY - 2025 AN - OPUS4-64446 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Müller, Thoralf A1 - Lehmann Schlag, Jens T1 - Grundlagen der Korrosion N2 - Der Vortrag behandelt die grundlegenden Reaktionen der Korrosion metallner Werkstoffe und erläutert das Prinzip der Passivität der nichtrostenden Stähle. Zusätzlich enthält der Vortrag beispielhafte Demoexperimente. T2 - Inhouse Seminar "Korrosionsverhalten nichtrostender Stähle" CY - Ravensburg, Germany DA - 15.10.2025 KW - Korrosion KW - Korrosionsschutz KW - Nichtrostende Stähle KW - Passivität PY - 2025 AN - OPUS4-64443 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Lehmann Schlag, Jens A1 - Müller, Thoralf T1 - Glänzende Aussichten - Aus Schäden wird man klug N2 - In diesem Beitrag werden Schadensbeispiele aus verschiedensten Branchenanwendungen nichtrostender Stähle gezeigt, die den Teilnehmern vor Augen führen sollen, an welchen Stellen Fehler zu Korrosionsschäden führen können. T2 - Inhouse Seminar "Korrosionsverhalten nichtrostender Stähle" CY - Ravensburg, Germany DA - 15.10.2025 KW - Korrosion KW - Nichtrostende Stähle KW - KorroPad KW - Metallografie KW - Korrosionsschutz PY - 2025 AN - OPUS4-64447 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Müller, Thoralf A1 - Lehmann Schlag, Jens T1 - Systematik und Gefügearten nichtrostender Stähle N2 - Der Vortrag erläutert die Bezeichnungssystematik nichtrostender Stahlsorten und stellt verschiedene Gefügearten und deren spezifische mechanisch-technologischen Eigenschaften gegenüber. T2 - Inhouse Seminar "Korrosionsverhalten nichtrostender Stähle" CY - Ravensburg, Germany DA - 15.10.2025 KW - Korrosion KW - Nichtrostende Stähle KW - Gefügearten KW - Stahlsorten PY - 2025 AN - OPUS4-64444 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - George, Joyal K. A1 - von Wangenheim, Kristian A1 - Kaplan, Felix A1 - Schneider, Ronald A1 - Hindersmann, Iris ED - Lienhart, Werner ED - Krüger, Markus T1 - Monitoring of civil engineering structures - current and future use cases N2 - Monitoring represents an effective approach for addressing the diverse challenges associated with the maintenance of civil engineering structures. It contributes to improving both the availability and safety of these structures. By increasing the amount of information available about the structure, monitoring supports better-informed decisions regarding its preservation. Due to the complexity of monitoring applications, specific use cases are outlined. A key advantage of these use cases is that new technologies can be tested within well-defined and limited scopes. The use cases monitoring of known, localized damage, monitoring of known deficits identified through reassessment or resulting from outdated design procedures and monitoring aimed at assessing traffic loads and their effects currently account for the majority of implemented monitoring measures. Their practical implementation is demonstrated through case studies from the Brandenburg State Road Authority. Additional use cases, such as monitoring to support structural inspections and monitoring of major structures, such as large viaducts, are gaining importance, with initial practical examples already present in Europe. Future applications reveal potential for expanded use, particularly in the context of monitoring to support predictive lifecycle management. This will become increasingly important in the implementation of digital twins, as announced in the national BIM master plan. Furthermore the concept of a Birth Certificate is intended to establish a reference state of the structure prior to commissioning, which can then be used for comparison with future measurements over time. The integration and interaction of these individual use cases pave the way for the implementation of digital twins. T2 - 13th International Conference on Structural Health Monitoring of Intelligent Infrastructure CY - Graz, Austria DA - 01.09.2025 KW - Structural Health Monitoring KW - Use Cases KW - Bridges KW - Digital Twin PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-644422 DO - https://doi.org/10.3217/978-3-99161-057-1-033 SP - 203 EP - 208 PB - Verlag der Technischen Universität Graz CY - Graz AN - OPUS4-64442 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Tidblad, Johan A1 - Moya Núñez, Alice A1 - de la Fuente, Daniel A1 - Ebell, Gino A1 - Flatlandsmo Berglen, Tore A1 - Grøntoft, Terje A1 - Hans, Ulrik A1 - Christodoulakis, Ioannis A1 - Kajánek, Daniel A1 - Kreislová, Kateřina A1 - Kwiatkowski, Lech A1 - La Torreta, Teresa A1 - Lutze, Rafał A1 - Pinar Larrubia, Guadalupe A1 - Pintus, Valentina A1 - Prange, Michael A1 - Spezzano, Pasquale A1 - Varotsos, Costas A1 - Verney-Carron, Aurélie A1 - Vuorio, Tiina A1 - Yates, Tim T1 - Corrosion and Soiling in the 21st Century: Insights from ICP Materials and Impact on Cultural Heritage N2 - This paper reviews results published by the International Co-operative Programme on Effects on Materials including Historic and Cultural Monuments (ICP Materials) with emphasis on those obtained after the turn of the century. Data from ICP Materials come from two main sources. The first is through exposures of materials and collection of environmental data in a network of atmospheric exposure test sites mainly distributed across Europe. Corrosion of carbon steel has continued to decrease during the period 2000–2020 but corrosion of zinc only up until 2014, and the trend in zinc corrosion is only visible when examining four-year data. Surface recession of limestone as well as soiling of modern glass show no decreasing trend during 2000–2020. The second is through case studies performed at heritage sites across Europe. Risk analysis of corrosion and soiling for twenty-six sites indicate that currently soiling is a more significant maintenance trigger than corrosion. Costs for maintaining heritage sites are substantial and costs attributable to air pollution is estimated from 40% to as much as 80% of the total cost. Future directions of the program are work on effects of particulate matter, improving the scientific basis for the work, and making the monitoring data publicly available. KW - Corrosion KW - Atmospheric corrosion KW - Soiling PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-644651 DO - https://doi.org/10.3390/cmd6040054 SN - 2624-5558 VL - 6 IS - 4 SP - 1 EP - 25 PB - MDPI AG AN - OPUS4-64465 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kemmler, Samuel T1 - Investigating Piping Erosion during Suction Bucket Installations using Fully-Resolved LBM-DEM Simulations N2 - Suction bucket foundations are an innovative, cost-effective, and environmentally sustainable solution for offshore wind turbine installations. Their deployment relies on generating suction pressure inside the bucket to achieve full embedment into the seabed. However, a critical challenge during installation is piping erosion, a process where particle fluidization beneath the bucket wall tip leads to a sudden drop in suction pressure, potentially causing installation failure. Despite its practical significance, the underlying physics governing piping erosion remain insufficiently understood due to the complex interplay between hydrodynamic forces and sediment transport. To bridge this knowledge gap, we employ a three-dimensional, fully-resolved coupled lattice Boltzmann method - discrete element method simulation to investigate the fundamental mechanisms driving piping erosion. The approach allows the capture of grain-scale interactions with high fidelity, enabling the identification of key parameters influencing erosion onset and progression. However, achieving physically representative problem sizes—comprising hundreds of thousands of grains—requires immense computational resources due to the high-resolution nature of the simulations. To address this computational challenge, simulations are performed on the LUMI supercomputer, leveraging hundreds of GPUs to execute large-scale, high-fidelity calculations. We present simulation results that showcase the method’s capability to resolve the intricate physics of piping erosion, offering new insights into the conditions that trigger erosion and its impact on suction bucket performance. These findings contribute to a deeper understanding of suction bucket installation dynamics and support the development of optimized, failure-resistant foundation designs for offshore wind applications. T2 - PARTICLES 2025 CY - Barcelona, Spain DA - 20.10.2025 KW - Micromechanical simulation KW - Suction bucket foundation KW - Piping erosion PY - 2025 AN - OPUS4-64460 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -