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 - 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 - JOUR A1 - Strangfeld, Christoph A1 - Küttenbaum, Stefan T1 - Zur Visualisierung von Schäden in Betonschwellen durch zerstörungsfreie Ultraschallprüfung N2 - Die bildgebende Ultraschalltechnik liefert Hinweise auf verdeckte Schäden in Spannbetonschwellen. Dieses zerstörungsfreie Prüfverfahren schafft eine objektive und vergleichbare Basis für die Zustandsbestimmung der Schwellen und ermöglicht die Optimierung von baulichen Erhaltungsstrategien. KW - Spannbetonschwellen KW - Zustandsbewertung KW - Verkehrsinfrastruktur PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-592914 UR - https://www.eurailpress.de/magazine.html SN - 0013-2845 IS - 12/23 SP - 26 EP - 31 PB - DVV Media Group CY - Hamburg AN - OPUS4-59291 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 - CONF A1 - Kanzler, D. A1 - Schmitt, M. A1 - Maack, Stefan A1 - Baensch, F. T1 - Erarbeitung einer Norm für einen standardisierten Prozess zur probabilistischen Bewertung von Prüfverfahren N2 - Im DIN-Normenausschuss Materialprüfung (NMP) wurde das Normungsgremium NA 062-08-28 AA „Qualifizierung von zerstörungsfreien Prüfungen“ reaktiviert. Das Ziel der Reaktivierung ist die Erarbeitung einer Norm für einen standardisierten Prozess zur probabilistischen Bewertung von Prüfverfahren. In der zerstörungsfreien Prüfung (ZfP) führt die Ermittlung von Mess- / Prüfunsicherheiten von Prüfverfahren, in normativer Hinsicht in Deutschland und Europa, noch ein Schattendasein. Die Norm ISO IEC 17025 und auch der VDA-Band 5 wurden weiter in Richtung Messunsicherheit entwickelt, allerdings führt ihre Anwendung in der ZfP zu Problemen. Der Arbeitsausschuss NA 062-08-28 AA soll hier den Brückenschlag zwischen Messunsicherheit, objektiver statistischer Bewertung für ZfP-Verfahren und eine weitere Stärkung der probabilistischen Bruchmechanik erreichen. Geplant ist daher die Erarbeitung einer DIN-Norm, welche die Kriterien für eine korrekte Versuchsplanung, ein praktikables Vorgehen zur Bewertung der Prüfergebnisse und die mathematische Überführung in eine Zuverlässigkeitsaussage enthält. Es soll ein Leitfaden erstellt werden, der für ein möglichst breites Branchenspektrum eingesetzt werden kann, unabhängig von den Besonderheiten verschiedener Industriezweige. Dargestellt werden das relevante Normungsgremium sowie der Hintergrund des zu erstellenden Dokuments. T2 - DGZfP Jahrestagung 2023 CY - Friedrichshafen, Germany DA - 15.05.2023 KW - Validation KW - Probabilistischen Bewertung KW - Zerstörungsfreie Prüfverfahren KW - POD PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-584176 UR - https://www.ndt.net/search/docs.php3?id=28574 SN - 978-3-947971-29-9 SP - 1 EP - 8 PB - NDT.net AN - OPUS4-58417 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Küttenbaum, Stefan A1 - Braml, T. A1 - Heinze, M. A1 - Kainz, C. A1 - Keuser, M. A1 - Kotz, P. A1 - Lechner, T. A1 - Maack, Stefan A1 - Reinke, K.-D. A1 - Schulze, S. A1 - Soukup, A. A1 - Stettner, C. A1 - Taffe, A. A1 - Wöstmann, Jens T1 - Guideline on NDT-supported reliability assessment of existing structures - Current developments in Germany N2 - Information about an existing structure can be collected at certain costs to evaluate the reliability and condition as realistically as necessary. This information can be relevant or irrelevant, true or biased, precise or imprecise. The incorporation of relevant and quality-assessed measured information into reliability reassessment offers the chance to extend remaining lifetimes and support decision making about optimal actions or maintenance strategies. This paper shows recent developments in a national research project that aims to produce a guideline on the NDT-based, structure-specific modification of partial safety factors. The general methodology, results from recalculations according to the Eurocodes and metrologically solvable testing tasks relevant in the recalculation of the concrete bridges are shown and compared with the non-destructive testing methods applicable to concrete bridges. A case study is used to demonstrate that as-built drawings, in this case of the positions of tendons and shear reinforcement, can be verified using the radar method. KW - Non-destructive testing KW - Concrete bridges KW - Partial safety factor modification PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-584862 DO - https://doi.org/10.1002/cepa.2168 SN - 2509-7075 VL - 6 IS - 5 SP - 537 EP - 543 PB - Ernst & Sohn CY - Berlin AN - OPUS4-58486 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Küttenbaum, Stefan A1 - Braml, T. A1 - Taffe, A. A1 - Maack, Stefan ED - Li, J. ED - Spanos, D. ED - Chen, J. B. ED - Peng, Y. B. T1 - Towards NDT-supported decisions on the reliability of existing bridges N2 - A major advantage in the reassessment of existing structures is the possibility of including measured data that describe the actual properties and the current condition of the structure to be reassessed. Currently, the incorporation of such measured information is mostly unregulated. However, the use of measurement results is vitally important, since a measured data-based improvement of the computation models level of approximation can lead at least to more meaningful results, possibly to extended remaining life times of the structure and in the best case to a saving of resources. Conversely, not appreciating well measurable and relevant information can be equated with a waste of resources. In this paper, a concept for the comparable use of non-destructively measured data as basic variables in probabilistic reliability assessments is outlined and examined using a typical prestressed concrete road bridge as a case-study. An essential requirement is the calculation of measurement uncertainties in order to evaluate the quality of the measurement results comparably. In conclusion, the example of ultrasonic and radar measurement data is used to demonstrate the effects that the incorporation of the measured information has on the reliability of the structure. T2 - 13th International Conference on Structural Safety and Reliability (ICOSSAR 2021-2022) CY - Online meeting DA - 13.09.2022 KW - Measurement uncertainty KW - Reliability assessment KW - Existing structures KW - Concrete Bridge KW - Non-Destructive Testing (NDT) PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-583013 SP - 1 EP - 10 AN - OPUS4-58301 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 - 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 - 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 - 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 - Gebauer, D. A1 - Gutiérrez, R, A1 - Marx, S. A1 - Butler, M. A1 - Grahl, K. A1 - Thiel, T. A1 - Maack, Stefan A1 - Küttenbaum, Stefan A1 - Pirskawetz, Stephan A1 - Breit, W. A1 - Schickert, M. A1 - Krüger, M. T1 - Interrelated dataset of rebound numbers, ultrasonic pulse velocities and compressive strengths of drilled concrete cores from an existing structure and new fabricated concrete cubes N2 - Two test series were examined using nondestructive measuring methods by six independent laboratories before determining their compressive strength. The nondestructive test methods used were the rebound hammer and ultrasonic pulse velocity measurement. Two types of geometries were investigated: drilled cores and cubes. The measurement procedure for each of these datasets is conditioned to the geometry and is therefore different. The first series consists of 20 drilled cores (approximately diameter/height = 10 cm/20 cm) from the 55-year-old Lahntal Viaduct near Limburg, Germany. After preparation in the first laboratory, the lateral surface of the drilled cores was tested with the rebound hammer using a given pattern. Every laboratory tested every drilled core at different locations. Ultrasonic measurements in transmission were performed repeatedly at predefined points on the flat surfaces of the specimen. The second series consisted of 25 newly manufactured concrete cubes of a mix with a target concrete strength class of C30/37. The edge length was 15 cm. Each laboratory received five specimens of this test series. Thus, contrary to the first series, each specimen was tested by only one laboratory. Two side faces of each cube were tested with the rebound hammer. In addition, ultrasonic measurements were performed by one laboratory. The time of flight was measured between the tested side faces of the rebound hammer at different positions. For both series, rebound hammers were used to determine the R-value as well as the Q-value. The rebound hammer models within the laboratories were always the same, while they differed between the laboratories. The ultrasonic measurements took place with different measurement systems and couplants. Finally, both specimen series were tested destructively for compressive strength. The dataset contains the raw data summarized in tabular form. In addition, relevant calculated data are included in some cases. For the ultrasonic measurements, the time of flight has already been converted into the ultrasonic velocity. Besides, in addition to the raw data of the compressive strength test (force, weight, and geometry values), the calculated compressive strengths and densities are also provided. KW - Nondestructive testing KW - Ultra sound KW - Rebound hammer KW - Existing structure KW - Civil engineering PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-574655 DO - https://doi.org/10.1016/j.dib.2023.109201 SN - 2352-3409 VL - 48 IS - 109201 SP - 1 EP - 13 PB - Elsevier Inc. AN - OPUS4-57465 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 - GEN A1 - Maack, Stefan A1 - Küttenbaum, Stefan A1 - Bühling, Benjamin T1 - Low-frequency ultrasound data (pulse-echo technique) with shear horizontal and longitudinal waves on the step-shaped concrete specimen “Pk050” N2 - This dataset contains raw data acquired in ultrasound measurements on a reference specimen made of concrete at Bundesanstalt für Materialforschung und -prüfung (BAM), Berlin (Germany). The internal specimen identifier is “Pk050”. The measurements were conducted using the pulse-echo method. The upper surface of the specimen was defined as measuring area. The aim of the measurements is to determine the geometrical dimensions (thickness) of the specimen “Pk050”. In addition to this, a dataset of a second specimen with identifier “Pk266” has been acquired. Pk266 has the same geometrical dimensions and concrete recipe as Pk050, but contains tendons [Reference: https://doi.org/10.7910/DVN/NUU0WZ]. KW - Ultrasound KW - Pulse echo method KW - Synthetic Aperture Focusing Technique KW - Validation KW - Elastic wave PY - 2023 DO - https://doi.org/10.7910/DVN/9EID5D PB - Harvard College CY - Cambridge, MA, USA AN - OPUS4-57231 LA - eng 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 - 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 - 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 - 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 - 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 - 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 - 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 - 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 - JOUR A1 - Karapanagiotis, Christos A1 - Hicke, Konstantin A1 - Krebber, Katerina T1 - Eine Sammlung durch Maschinelles Lernen unterstützter Verteilter Faseroptischer Sensoren für Infrastrukturmonitoring T1 - A collection of machine learning assisted distributed fiber optic sensors for infrastructure monitoring N2 - In this paper, we present a collection of machine learning assisted distributed fiber optic sensors (DFOS) for applications in the field of infrastructure monitoring. We employ advanced signal processing based on artificial neural networks (ANNs) to enhance the performance of the dynamic DFOS for strain and vibration sensing. Specifically, ANNs in comparison to conventional and computationally expensive correlation and linearization algorithms, deliver lower strain errors and speed up the signal processing allowing real time strain monitoring. Furthermore, convolutional neural networks (CNNs) are used to denoise the dynamic DFOS signal and enable useable sensing lengths of up to 100 km. Applications of the machine learning assisted dynamic DFOS in road traffic and railway infrastructure monitoring are demonstrated. In the field of static DFOS, machine learning is applied to the well-known Brillouin optical frequency domain analysis (BOFDA) system. Specifically, CNN are shown to be very tolerant against noisy spectra and contribute towards significantly shorter measurement times. Furthermore, different machine learning algorithms (linear and polynomial regression, decision trees, ANNs) are applied to solve the well-known problem of cross-sensitivity in cases when temperature and humidity are measured simultaneously. The presented machine learning assisted DFOS can potentially contribute towards enhanced, cost effective and reliable monitoring of infrastructures. N2 - In diesem Beitrag stellen wir eine Sammlung von verteilten faseroptischen Sensoren (DFOS) vor, die mit Hilfe von Maschinellem Lernen arbeiten und für Anwendungen im Bereich der Infrastrukturüberwachung geeignet sind. Wir setzen hierbei fortschrittliche Signalverarbeitung auf der Grundlage Künstlicher Neuronaler Netze ein, um die Leistungsfähigkeit dynamischer DFOS für die Messung von Dehnungen und Vibrationen zu verbessern. Insbesondere Künstliche Neuronale Netze (ANNs) liefern im Vergleich zu konventionellen und rechenintensiven Korrelations- und Linearisierungsalgorithmen geringere Dehnungsfehler und beschleunigen die Signalverarbeitung, so dass eine Dehnungsüberwachung in Echtzeit möglich ist. Darüber hinaus wenden wir Convolutional Neural Networks (CNNs) an, um dynamische DFOS-Signale zu entrauschen und damit nutzbare Messlängen von bis zu 100 km zu ermöglichen. Es werden Anwendungsbeispiele dieser durch Maschinelles Lernen unterstützten dynamischen DFOS in den Bereichen des Straßenverkehrsmonitorings und der Zug- und Gleisüberwachung aufgezeigt. Im Bereich der statischen DFOS wird Maschinelles Lernen auf das Verfahren der Optischen Brillouin-Frequenzbereichsanalyse (BOFDA) angewendet. Insbesondere CNN erweisen sich hier als sehr robust gegenüber verrauschten Spektren und tragen zu deutlich kürzeren Messzeiten bei. Darüber hinaus werden verschiedene Algorithmen des maschinellen Lernens (lineare und polynome Regression, Entscheidungsbäume, ANNs) angewandt, um das bekannte Problem der Querempfindlichkeit bei DFOS in den Fällen zu lösen, in denen Temperatur und Feuchtigkeit gleichzeitig gemessen werden sollen. Die hier vorgestellten, durch Maschinelles Lernen unterstützten, DFOS können zu einer verbesserten, kostengünstigen und zuverlässigen Überwachung von Infrastrukturen beitragen. KW - Artificial neural networks KW - Brillouin sensing KW - Distributed acoustic sensing KW - Fibre optic sensors KW - Infrastructure monitoring PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-569044 DO - https://doi.org/10.1515/teme-2022-0098 SN - 0171-8096 SP - 1 EP - 19 PB - De Gruyter AN - OPUS4-56904 LA - mul 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 - 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 - 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 - CHAP A1 - Bartolac, M. A1 - Bien, J. A1 - Górski, M. A1 - Keßler, S. A1 - Küttenbaum, Stefan A1 - Kuzawa, M. A1 - Ley, J. A1 - Maack, Stefan A1 - Mendler, A. A1 - Ryjáček, P. A1 - Santos, L. A1 - Verstrynge, E. ED - Keßler, S. ED - Limongelli, M. P. ED - Apostolidi, E. T1 - Chapter 2: Condition survey - Testing and monitoring methods N2 - The through-life management of our constantly ageing infrastructure is a basic requirement in order to ensure their structural safety and serviceability. Each structure experiences deterioration processes with time leading to a decrease of structural safety and serviceability. The design of new structures considers the expected deterioration for a defined period, the design service life. However, a frequent survey of structural safety controlling structural condition should be mandatory and a maintenance plan should be an integral part of the design. In addition, many structures have exceeded their design service life already or are very close to it leading to an increasing demand for condition assessment. On the one hand, assumptions made during design are not valid any more due to change of the loads, e.g., increasing traffic loads in terms of number and weights. On the other hand, design codes evolved over time in such a way that existing structures do not comply with today’s standards. In all these cases, the through-life management is an important tool to maintain the accessibility of existing structures with known reliability. In line with the new Model Code for Concrete Structures, which includes guidance for both – design of new structures and assessment of existing structures, the Task Group 3.3 focused on the compilation of a state-of-the-art guideline for the through-life management of existing concrete structures, including: Data acquisition by testing and monitoring techniques; Condition assessment for the evaluation of existing structures; Performance prediction using advanced methods; Decision-making procedures to perform a complete assessment of existing structure. The overall objective of the through-life management is the assessment of the current condition and the estimation of the remaining service life under consideration of all boundary conditions. KW - Life management KW - Concrete KW - Non-destructive testing KW - Structural health monitoring KW - State-of-the-art PY - 2023 UR - https://doi.org/10.35789/fib.BULL.0109 SN - 978-2-88394-172-4 DO - https://doi.org/10.35789/fib.BULL.0109.Ch02 SN - 1562-3610 VL - fib Bulletin 109 SP - 16 EP - 38 PB - Fédération internationale du béton (fib) CY - Lausanne AN - OPUS4-59110 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 - JOUR A1 - Karapanagiotis, Christos A1 - Krebber, Katerina T1 - Machine Learning Approaches in Brillouin Distributed Fiber Optic Sensors N2 - This paper presents reported machine learning approaches in the field of Brillouin distributed fiber optic sensors (DFOSs). The increasing popularity of Brillouin DFOSs stems from their capability to continuously monitor temperature and strain along kilometer-long optical fibers, rendering them attractive for industrial applications, such as the structural health monitoring of large civil infrastructures and pipelines. In recent years, machine learning has been integrated into the Brillouin DFOS signal processing, resulting in fast and enhanced temperature, strain, and humidity measurements without increasing the system’s cost. Machine learning has also contributed to enhanced spatial resolution in Brillouin optical time domain analysis (BOTDA) systems and shorter measurement times in Brillouin optical frequency domain analysis (BOFDA) systems. This paper provides an overview of the applied machine learning methodologies in Brillouin DFOSs, as well as future perspectives in this area. KW - Distributed fiber optic sensors KW - BOTDA KW - BOFDA KW - Machine learning KW - Strain and temperature measurements KW - Artificial neural networks PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-580145 DO - https://doi.org/10.3390/s23136187 VL - 23 IS - 13 SP - 1 EP - 26 PB - MDPI AN - OPUS4-58014 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Karapanagiotis, Christos A1 - Hicke, Konstantin A1 - Krebber, Katerina T1 - Machine learning assisted BOFDA for simultaneous temperature and strain sensing in a standard optical fiber N2 - We report, to our knowledge for the first time on simultaneous distributed temperature and strain sensing in a standard telecom optical fiber using a machine learning assisted Brillouin frequency domain analysis (BOFDA) system. The well-known temperature and strain cross-sensitivity problem is addressed by developing a BOFDA system with a high signal-to-noise ratio and applying machine learning. The spectrum consists of four highly resolved peaks, whose Brillouin frequency shifts are extracted and serve as features for the machine learning algorithms. The spectra result from a 450-m standard SMF-28 optical fiber, and particularly from a segment of 30 m. This fiber segment is coiled around a stretcher and placed in a climate chamber. The applied temperature and strain values range from 20 °C to 40 °C and from 0 µɛ to 1380 µɛ, respectively. The total measurement time to achieve a high SNR and resolve four peaks with a spatial resolution of 6 m is 16 min. To discriminate temperature and strain effects, simple frequentist and more sophisticated Bayesian-based algorithms are employed with the powerful Gaussian process regression (GPR) delivering the best performance in terms of temperature and strain errors, which are found to be 2 °C and 45 µɛ, respectively. These errors are calculated using leave-one-out cross-validation, so that an unbiased estimation of the sensor’s performance is provided. KW - Machine learning KW - Brillouin distributed fiber optic sensors KW - Temperature and strain sensing KW - BOFDA PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-569155 DO - https://doi.org/10.1364/OE.480224 SN - 1094-4087 VL - 31 IS - 3 SP - 5027 EP - 5041 PB - OPTICA AN - OPUS4-56915 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Scheuschner, Nils T1 - Emissivity Prediction of Rough Cast Iron for Laser Thermography N2 - This study presents a method for predicting the emissivity of rough cast iron surfaces to enhance the accuracy of laser thermography in industrial non-destructive testing (NDT). Traditional emissivity measurements are impractical in industrial settings due to environmental interference and equipment limitations. The proposed approach replaces complex setups like integrating spheres with a simplified illumination unit and reflection measurements. By leveraging known material properties and surface characteristics, an algorithm predicts directional emissivity. Experimental results of an initial feasibility study show strong agreement between predicted and measured values, demonstrating the method’s potential for real-time emissivity correction in industrial thermographic inspections. T2 - Advanced Infrared Technology and Applications (AITA) 2023 CY - Venice, Italy DA - 10.09.2023 KW - Thermography KW - Laser KW - NDT KW - Cast iron PY - 2023 AN - OPUS4-63121 LA - eng 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 - 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 - 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 - 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 - 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 - 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 - 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 - 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 - 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 - Karapanagiotis, Christos T1 - Machine learning for strain, temperature and humidity discrimination in Brillouin optical frequency domain analysis N2 - We propose to our knowledge for the first time an ensemble of probabilistic machine learning models for strain, temperature and humidity discrimination in Brillouin optical frequency domain analysis (BOFDA) applying a two-fiber configuration. T2 - 28th International Conference on Optical Fiber Sensors CY - Hamamatsu, Japan DA - 20.11.2023 KW - Multiparameter sensing KW - Fiber optic sensors KW - Machine learning KW - Structural health monitoring PY - 2023 AN - OPUS4-59396 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 -