TY - JOUR A1 - Geoerg, Paul A1 - Schumann, Jette A1 - Holl, Stefan A1 - Holl, Maik A1 - Hofmann-Böllinghaus, Anja T1 - The influence of individual impairments in crowd dynamics N2 - The importance of empirical relations to quantify the movement of pedestrians through a facility has increased during the last decades since performance-based design methods became more common. Bottlenecks are of special interest because of their importance for egress routes and as they result in a reduced capacity. The empirical relations as the density-dependent movement speed or flow rate were derived by studies under laboratory conditions, which were usually conducted with populations of homogeneous characteristics forbetter control of influencing variables. If individual characteristics of a crowd become more heterogeneous, individuals were forced to adapt their individual movement and control individual manoeuvring. These unintended interactions lead to a different shape of the fundamental empirical relations. Here, we present results from a movement study under well-controlled boundary conditions in which participants with and without different characteristics of disabilities participated. To consider the effect of different heterogeneities on the capacity of a facility, fundamental diagrams are generated using the Voronoi method. If participants with visible disabilities (such as using assistive devices) are part of a crowd, significant differences relating to the shape of the empirical Relations and the capacities are found. This indicates that the heterogeneity of a Population leads to an increased interpersonal interaction which results in influenced movement characteristics. KW - Engineering egress data KW - Heterogeneity KW - Human behaviour KW - Movement characteristics KW - Pedestrian dynamics PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-508943 DO - https://doi.org/10.1002/fam.2789 SN - 0308-0501 VL - 45 IS - 4 SP - 529 EP - 542 PB - Wiley Online Libary CY - New Jersey, USA AN - OPUS4-50894 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Piechnik, Kira A1 - Hofmann-Böllinghaus, Anja A1 - Klippel, Andrea T1 - Self‐ignition of forest soil samples demonstrated through hot storage tests N2 - AbstractThe increasing threat of forest fires on a global scale is not only a matter of concern due to the potential harm they may cause to both human and animal life but also due to their significant role in exacerbating climate change. In light of these circumstances, one might inquire as to whether forest soil can self‐ignite and, if so, under what conditions and at what temperatures this phenomenon may occur. This question is being addressed in the German pilot “Fire science of wildfires and safety measures” of the EU project TREEADS, and the first results are presented below. The importance of basic research into the self‐ignition of forest soil cannot be underestimated, as it provides crucial knowledge to prevent forest fires and protect human and animal health. Furthermore, mitigating the occurrence of forest fires can also play a role in reducing greenhouse gas emissions, contributing to global efforts to combat climate change. The procedure of the hot storage test is an effective means of determining whether a material can self‐ignite. During the investigation of six soil samples, it was found that five of them were indeed capable of self‐ignition. In addition to determining whether the material ignites, the modified hot storage test also analyzed the resulting smoke gases and measured their concentration. The research question of whether regional forest soil is capable of self‐ignition can be answered with yes based on these initial tests. Further experiments are needed to determine if self‐ignition causes forest fires. KW - FTIR KW - Hot storage KW - Ignition KW - Soil KW - Wildfire PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-594617 DO - https://doi.org/10.1002/fam.3198 SN - 1099-1018 VL - 48 IS - 4 SP - 495 EP - 507 PB - Wiley CY - New York, NY AN - OPUS4-59461 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - THES A1 - Kempel, Florian T1 - Komplementäre Nutzung von Polymerwissenschaft und Brandsimulation: Vier Beispiele in den Dimensionen Kubikdekameter bis Kubikzentimeter N2 - Vereint unter dem Begriff Ingenieurmethoden haben Brandsimulationen Eingang in die Fortentwicklung des Baurechts gefunden und werden vermehrt zur Unterstützung von Brandschutzkonzepten und -nachweisen eingesetzt. Aktuelle Software verbindet Verbrennungsmodelle mit numerischer Strömungsmechanik und eignet sich so für die flexible Bearbeitung unterschiedlichster Fragestellungen. Darüber hinaus bieten erste Programme die Möglichkeit, Untermodelle zur Beschreibung des Feststoffabbrands bzw. der Pyrolyse von Brandlasten einzufügen. In der Polymerwissenschaft stellt die Untersuchung und Optimierung des Brandverhaltens einschließlich der Pyrolyse eine wichtige Aufgabe dar. Aufgrund des Brandrisikos ist die Verwendung polymerer Werkstoffe häufig eingeschränkt. Die Entwicklung flammgeschützter Materialien hat daher eine besondere Bedeutung und es existieren detaillierte Methoden zur Charakterisierung brandrelevanter Materialeigenschaften. Vor diesem Hintergrund zielt die vorliegende Arbeit darauf ab, die Potentiale und Herausforderungen der komplementären Nutzung von Brandsimulation und polymerwissenschaftlichen Methoden zu untersuchen. Hierfür wurden vier Brandszenarien ausgewählt: Der Brand in einem Einfamilienhaus in der Dimension Kubikdekameter (dam³), der Single Burning Item SBI Test in der Dimension Kubikmeter (m³), der Cone Kalorimeter Test in der Dimension Kubikdezimeter (dm³) und der UL 94 Test in der Dimension Kubikzentimeter (cm³). Die Brandszenarien werden zunächst ausführlich charakterisiert. Anschließend wird ein jeweils passendes Simulationsmodell erstellt und berechnet und die Berechnungsergebnisse werden mit den realen Ausprägungen verglichen. Schließlich werden die Simulationen, unterstützt durch eine Parameterstudie, bewertet. In den Untersuchungen zu den vier Brandszenarien werden durch die komplementäre Nutzung von Brandsimulation und Polymerwissenschaft belastbare numerische Berechnungen erarbeitet. Grundlage für die Ergebnisse sind die detaillierte Charakterisierung der brandrelevanten physikalischen und chemischen Eigenschaften der Werkstoffe und die damit verbundene Qualität der Eingabeparameter. Für das Brandszenario Einfamilienhaus wird der Brandverlauf in einer komplexen Geometrie mit unterschiedlichen Brandlasten realistisch berechnet. Für den SBI Test und den Cone Kalorimeter Test stehen die Wärmefreisetzungsrate bzw. die Massenverlustrate im Mittelpunkt der Simulation und zeigen eine hohe Übereinstimmung mit den experimentellen Ergebnissen. Für den vertikalen UL 94 Test werden darüber hinaus erstmals das komplexe Zusammenspiel von Pyrolyse, Verbrennung und Tropfverhalten simuliert und die unterschiedlichen Klassifizierungen und Zeitmaßstäbe übereinstimmend mit den Experimenten aus den Berechnungen abgeleitet. Anhand der Beispiele werden erweiterte Anwendungsbereiche von Brandsimulationen durch gezielte Nutzung der polymerwissenschaftlichen Kenntnisse aufgezeigt. Gleichzeitig weisen insbesondere die Untersuchungen zu den Brandszenarien Cone Kalorimeter Test und UL 94 Test auf den wertvollen Beitrag von Brandsimulationen für die Polymerwissenschaft hin. Durch Parametervariationen können aufbauend auf einem validierten Simulationsmodell zusätzliche Erkenntnisse über die Struktur-Eigenschaftsbeziehungen von Polymeren hinsichtlich des Brandverhaltens gewonnen werden, um die Entwicklung flammgeschützter Materialien zielführend zu unterstützen. N2 - Termed as engineering methods, fire simulations have found their way into building legislation and are frequently used to support concepts and verifications of structural fire protection plans. Recent software developments combine combustion models and computational fluid dynamics and therefore qualify for the processing of a wide variation of tasks and questions. Above all, latest programs provide the opportunity of adding further submodels in order to describe the fire behaviour of solid fuels, i.e. the thermal decomposition or pyrolysis of the materials can be calculated. In polymer science, the research and development of the fire behavior of materials is a scientific task of its own. Due to the fire risk, the application of polymers is often restricted. Hence, the development of fire retarded materials is of particular importance and existing methods are being used to characterize in detail all aspects of material properties according to its reaction to fire. According to this, the aims of this thesis were to investigate the capabilities and challenges of the complementary use of fire simulation and polymer science. Four different fire scenarios were chosen for the analysis: a fire case in a family home in the dimension of cubic decameter (dam³), the Single Burning Item SBI test in the dimension of cubic meter (m³), the Cone Calorimeter test in the dimension of cubic decimeter (dm³) and the UL 94 test in the dimension of cubic centimeter (cm³). The investigation involved a thorough characterization of those scenarios as well as the creation and calculation of a simulation model for each scenario. Subsequently simulation was compared to the real characteristics and an evaluation, supported by parameter analysis, provided. By analyzing the four fire scenarios and due to the complementary use of fire simulation and polymer science, numeric calculations have lead to significant results. Those are based upon the detailed characterization of the fire related physical and chemical properties of materials and the associated quality of the input parameters. For the family-homescenario the fire spread is calculated realistically within a complex geometry with different fire loads. For the fire scenarios SBI and Cone Calorimeter test, which focus on the calculated heat release rate and the mass loss rate, respectively, a very close agreement with the experimental results was achieved. For the fire scenario UL 94 test the interaction of gasification, combustion and melt dripping is being simulated for the first time and the UL 94 classifications of the materials as well as the time scales are derived in accordance with the experimental results. On the basis of the four examples as shown above, and by the systematic use of polymer science, this thesis demonstrates extended ranges of applications of fire simulations. At the same time the considerable contribution of fire simulations to polymer science is highlighted in particular during the analysis of the fire scenarios Cone Calorimeter and the UL 94 test. Based on the validated model, parameter variations reveal additional insight into the structure-property-relationship of polymers regarding their fire behavior, which may guide the development of fire retarded materials. T3 - BAM Dissertationsreihe - 104 KW - Polymer KW - Brandverhalten KW - Pyrolyse KW - Brandsimulation KW - CFD PY - 2013 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-545 SN - 978-3-9815748-5-2 SN - 1613-4249 VL - 104 SP - 1 EP - 173 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-54 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Nandish, Ranjith A1 - Knaust, Christian A1 - Hofmann-Böllinghaus, Anja A1 - Gnutzmann, Tanja A1 - Zehfuß, Jochen T1 - Simulation of wood pyrolysis with component-based mechanism N2 - This paper presents a comprehensive fire simulation study that models the pyrolysis process of beech wood using kinetic parameters with the Fire Dynamics Simulator (FDS). The kinetic methodology is based on the application of these kinetic parameters to govern the underlying pyrolysis reactions. The primary objective was to numerically model the pyrolysis process for beech wood using both single-component (single-step, single reaction scheme) and multi-component (single-step, multi-reaction scheme) kinetic reaction schemes. The accuracy of the numerical model was validated by comparing FDS simulation results with experimental data obtained from thermogravimetric analysis (TGA) and cone calorimeter tests. This approach aids in identifying reliable kinetic reaction input parameters for modelling wood fires. A case study was included to demonstrate the implementation of the kinetic reaction schemes. Numerical results from the TGA simulations for the small-scale pure cellulose test using the single-component approach exhibit consistency with the experimental data. Furthermore, the results demonstrated that the multi-component approach more accurately replicates the shape of the experimental curve for beech wood compared to the single-component approach. However, discrepancies in the tail regions of the curves obtained from the FDS simulations showed the need for further improvement in the modelling approach, particularly regarding the exclusion of char oxidation reactions, which needs to be investigated further. KW - Simulation KW - Wood PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-639272 DO - https://doi.org/10.1007/s00231-025-03571-7 SN - 0947-7411 VL - 61 IS - 6 SP - 1 EP - 14 PB - Springer Science and Business Media LLC AN - OPUS4-63927 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hofmann-Böllinghaus, Anja A1 - Klippel, Andrea A1 - Gnutzmann, Tanja A1 - Kaudelka, Sven A1 - Rabe, Frederik T1 - Influence of modern plastic furniture on the fire development in fires in homes: large-scale fire tests in living rooms N2 - About 80% of all fire fatalities in Germany occur because of fires in homes. It has been known for some time that modern materials (synonym for materials consisting mostly of synthetic polymers) tend to burn differently from older materials (synonym for materials consisting mostly of fibrous cellulosic substances) and it has been acknowledged that the amount of combustible plastics in homes has increased significantly over the last decades. To investigate the influence of modern furniture and ventilation conditions of fires in homes, a series of four large-scale tests in two Living rooms (LRs) with adjacent rooms (ARs) was performed by BAM and the Frankfurt fire service. Two LRs, one with older furniture and one with modern furniture, were tested twice each. Each test started with the ignition of a paper cushion on an upholstered chair. The influence of modern materials on the fire development was investigated, as well as the influence of the ventilation on the fire development. In all settings, an upholstered chair was the first burning item. Results of the test series show that fires in rooms with modern furniture develop faster than fires in rooms with older furniture. This is true for temperature development in the rooms as well as for smoke production. KW - Room fire KW - Furniture KW - Modern KW - Gas analysis KW - Smoke PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-527568 DO - https://doi.org/10.1002/fam.2934 VL - 45 IS - 1 SP - 155 EP - 166 PB - Wiley CY - London AN - OPUS4-52756 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Manes, M. A1 - Sauca, A. A1 - El Houssami, M. A1 - Andersson, P. A1 - McIntyre, C. A1 - Campbell, R. A1 - Rush, D. A1 - Hofmann-Böllinghaus, Anja A1 - Wagner, P. A1 - Leene, M. A1 - Oberhagemann, D. A1 - Jomaas, G. A1 - Grone, F. A1 - Guillaume, E. T1 - Closing Data Gaps and Paving the Way for Pan-European Fire Safety Efforts: Part II—Terminology of Fire Statistical Variables N2 - A well-defined terminology of fire-related variables is important for correct analyses and supporting knowledge-based decisions regarding the evaluation of building fires at the European level. After developing an overview of current practices for fire statistics in Part I, the terminology used and the data collected by the EU Member States and eight other countries regarding fire incidents, property damage and human losses were mapped to increase awareness of their practice and support a comprehensive assessment of several fire statistical datasets. A questionnaire was distributed to relevant authorities responsible for the collection, elaboration/analysis, and fire statistical data publications to define and select the essential variables for an appropriate fire assessment and fire incident description. Based on the results of the questionnaire able to identify the essential fire statistical variables and a detailed analysis of current definitions adopted in the fire statistics of the EU Member States and other countries, a common terminology is proposed to collect the necessary data in the EU Member States and obtain meaningful datasets based on standardised terms and definitions. The results will generate essential outputs to move towards harmonised fire statistics at the EU level and contribute to an appropriate analysis able to improve fire prevention and fire mitigation in building fires. KW - Fire statistics PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-575725 DO - https://doi.org/10.1007/s10694-023-01408-5 SN - 1572-8099 SP - 1 EP - 32 PB - Springer CY - Heidelberg AN - OPUS4-57572 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Mezhov, Alexander A1 - Kulisch, D. A1 - Goncharov, A. A1 - Zhutovsky, S. T1 - A Comparative Study of Factors Influencing Hydration Stoppage of Hardened Cement Paste N2 - There is no consensus on which hydration stoppage method is optimal to preserve the microstructure and mineral composition of samples, especially considering the specific aspects of different testing methods, such as TGA, MIP, or XRD. This paper presents a quantitative comparison between the most popular hydration stoppage strategies and parameters such as the sample piece size, the soaking time in a solvent, and the type, as examined on cement paste hydrated for 7 days. It was found that the carbonation appears either for samples smaller than 2.36 mm and bigger than 4.75 mm or samples soaked in a solvent for longer than 1 h. Fast solvent replacement leads to ettringite diminution and total pore volume increase. Among others, solvent replacement with subsequent gentle heating under a vacuum was found to be the most efficient, whereas it was experimentally demonstrated that isopropyl alcohol stops hydration faster than ethanol and acetone. KW - Hydration stoppage KW - Solvent replacement KW - Soaking time KW - Sample piece size PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-582430 DO - https://doi.org/10.3390/su15021080 VL - 15 IS - 2 SP - 1 EP - 21 PB - MDPI CY - Basel, Switzerland. AN - OPUS4-58243 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Strangfeld, Christoph A1 - Schönsee, Eric A1 - Jeyifous, Olubunmi Anthony A1 - Mezhov, Alexander A1 - Hüsken, Götz T1 - Introduction of a monitoring system for Bingham fluids in additive manufacturing with concrete N2 - Freeform additive manufacturing of concrete structures is a rising technology in civil engineering with several fascinating advantages. Nonetheless, to ensure reliability and structural integrity, standards and quality control are required in the future to bring this technology into the market. As the concrete is manufactured continuously, continuous quality control of the printing process is also required, i.e. comprehensive process monitoring. At BAM, a test rig will be installed, enabling the printing of concrete structures with a maximum size of 2 m x 1 m x 1 m (l x w x h). Here, process monitoring is the focus of the test rig. In this study, we show the results of the first pump tests, including the measurement of several parameters such as temperature and pressure along the supply system, i.e. from the concrete pump to the printer head. T2 - NDT-CE 2022 CY - Zurich, Switzerland DA - 16.08.2022 KW - Additive manufacturing of concrete KW - Process monitoring KW - Non-destructive testing KW - Bingham fluid PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-556367 SP - 1 EP - 12 AN - OPUS4-55636 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Unger, Jörg F. T1 - From scientific models to reliable decision making – RDM as a backbone for validated, FAIR, and reproducible engineering simulations N2 - Engineering simulations play a central role in predicting system behavior and supporting design decisions. Their impact will increase due to the concepts of virtual lab, digital twins and predictive maintenance, where expensive prototyping is reduced with simulations or where real measurement data of the structures or parts are used in combination with simulation models to improve decision making. The credibility of a simulation model depends on the trust it earns within the scientific and engineering community. This trust can only be established through rigorous verification and validation. Verification and validation are inherently hierarchical processes. At the highest level, global approaches—such as standardized benchmarks and shared validation datasets—provide a common foundation for assessing model correctness and applicability across domains. These global resources enable regulatory bodies, industry, and research communities to evaluate whether models and their implementations meet agreed-upon standards. Research Data Management (RDM) provides the infrastructure to support these processes by enabling formalized model definitions, structured validation datasets, and transparent verification procedures and complete provenance descriptions of the underlying workflows. Currently, many engineering models are published as descriptive text or embedded in specific software implementations, which hinders reproducibility and standardization. Numerical results presented in publications must be fully reproducible. For regulatory assessment and interoperability, models require software-agnostic, machine-readable definitions that include all information needed for implementation and execution, such as scope, assumptions, parameter identification procedures, and uncertainty bounds. Formal definitions alone do not guarantee consistency. Verification benchmarks are essential to confirm that different implementations of the same mathematical or numerical model produce equivalent results. Likewise, validation requires structured experimental data that is publicly available and documented according to community-agreed protocols for tests, measurements, and metadata. Robust calibration and uncertainty quantification frameworks must provide systematic, reproducible procedures for parameter estimation and uncertainty propagation, while the complete provenance of these steps has to be documented. Validation should extend beyond controlled laboratory conditions to diverse real-world scenarios. The presentation will explore practical strategies for achieving reproducibility and reusability in engineering simulations through structured workflows, provenance tracking, and standardized data management practices. It will address the integration of experimental data for validation, the role of verification benchmarks, uncertainty quantification frameworks, and tool-independent model descriptions—including VMAP for result exchange—within collaborative platforms that support joint projects and regulatory compliance. T2 - GAMM Activity Group on Research Software Engineering and Research Data Management in Mathematics & Mechanics (GAMM FA RSE&RDM) CY - Braunschweig, Germany DA - 04.12.2025 KW - Experimental data KW - Verification and validation KW - UQ KW - Reproducibility (workflows) KW - Reusability (provenance tracking of simulation results) PY - 2025 AN - OPUS4-65267 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Unger, Jörg F. T1 - Methodological prerequisites for reliable simulation results in the Virtual Lab and Digital Twins N2 - Mit dem zunehmenden Einsatz von Methoden wie Künstlicher Intelligenz, Digitalen Zwillingen und datengetriebener Modellierung erweitert sich das Anwendungsspektrum der virtuellen Produktentwicklung kontinuierlich. In sicherheitsrelevanten Anwendungsfeldern steigen dabei die Anforderungen an die Qualität, Nachvollziehbarkeit und externe Prüfbarkeit von Simulationsergebnissen – insbesondere im Hinblick auf Reproduzierbarkeit und Transparenz. Der Beitrag analysiert zentrale methodische und strukturelle Herausforderungen für den zuverlässigen Einsatz numerischer Simulationen in solchen Kontexten. Im Mittelpunkt stehen folgende Aspekte: • Die formale, softwareunabhängige Spezifikation mathematischer und numerischer Modelle, einschließlich einer standardisierten Beschreibung sowohl der Problemstellung als auch der Ergebnisgrößen. • Die Validierung sämtlicher Modellkomponenten anhand von Anwendungsszenarien mit hoher Ähnlichkeit zur realen Systemumgebung. • Die systematische Quantifizierung von Unsicherheiten, insbesondere im Hinblick auf Sim2Real-Modellabweichungen und deren Einfluss auf die Aussagekraft der Simulation. • Die Verifikation der Softwareimplementierung durch standardisierte Benchmark-Vergleiche. Hierzu wird ein Konzept föderierter Benchmarks mit dokumentierter Herkunft („Provenance“) vorgestellt, das eine transparente, reproduzierbare und öffentlich zugängliche Verifikation von Simulationswerkzeugen ermöglicht. Die Benchmarks folgen definierten Formaten, können dezentral veröffentlicht und in eine zentrale, abfragbare Datenbank integriert werden. Durch diese standardisierten Schnittstellen können dann Metriken zum Vergleich der Benchmarks visualisiert und in Analysen bereitgestellt werden. Der Beitrag zielt darauf ab, zentrale Herausforderungen und offene Fragestellungen bei der methodischen Absicherung simulationsbasierter Aussagen zu identifizieren und zur Diskussion zu stellen – insbesondere im Spannungsfeld zwischen Modellbildung, Validierung, Verifikation und Unsicherheitsquantifizierung. T2 - Symbiose von Simulation und Test CY - Wiesbaden, Germany DA - 12.11.2025 KW - Structured validation data KW - Model calibration KW - UQ PY - 2025 AN - OPUS4-65270 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Jafari, Abbas T1 - A python library for finite element (FE) modelling of static/quasi-static structural mechanics problems with legacy FEniCS N2 - This is a python library for finite element (FE) modelling of static/quasi-static structural mechanics problems with legacy FEniCS, which contains the following main modules. Module structure: for defining a structural mechanics experiment, including geometry, mesh, boundary conditions (BCs), and time-varying loadings. The time is quasi-static, i.e. no dynamic (inertia) effects will be accounted for in the problem module as follows. Module material: for handling constitutive laws such as elasticity, gradient damage, plasticity, etc. Module problem: for establishing structural mechanics problems for desired structures and material laws coming from the two above modules, and solving the problems built up. These can be performed for two main cases: static (no time-evolution) that also includes homogenization, and quasi-static (QS). KW - Finite element (FE) KW - Static/quasi-static structural mechanics KW - FEniCS PY - 2025 DO - https://doi.org/10.5281/zenodo.17805724 PB - Zenodo CY - Geneva AN - OPUS4-65269 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Jafari, Abbas A1 - Titscher, Thomas A1 - Robens-Radermacher, Annika T1 - Bayem: Implementation and derivation of “variational Bayesian inference for a nonlinear forward model [Chappell et al 2008]“ for arbitrary, user-defined model errors N2 - A python implementation of an analytical variational Bayes algorithm of "Variational Bayesian inference for a nonlinear forward model", Chappell, Michael A., Adrian R. Groves, Brandon Whitcher, and Mark W. Woolrich, IEEE Transactions on Signal Processing 57, no. 1 (2008): 223-236, with an updated free energy equation to correctly capture the log evidence. The algorithm requires a user-defined model error allowing an arbitrary combination of custom forward models and measured data. KW - Implementation KW - Variational Bayesian inference KW - Nonlinear forward model PY - 2025 DO - https://doi.org/10.5281/zenodo.17804665 PB - Zenodo CY - Geneva AN - OPUS4-65268 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Robens-Radermacher, Annika T1 - Modeling the influence of temperature for extrusion based 3d concrete printing from material to structural stability N2 - Abstract: 3D concrete printing (3DCP) aims to revolutionize construction by increasing automation, reducing material usage, and enabling customized designs. Despite its potential, the lack of regulations and reliance on trial-and-error methods result in significant waste and inefficiencies. Reliable models are needed to predict and control the complex printing process with its various influencing factors from material, process, and environment. This study aims to develop a structural model to predict print stability and prevent buckling and material failure in extrusion-based 3D concrete printing (3DCP), with a focus on environmental influences, particularly temperature. The structural build-up of the material is crucial for stability but is influenced by material ingredients, water-binder ratio, and ambient conditions, which vary in real-world projects. It describes the process of cementitious material gaining strength and stability during its early ages due to thixotropy and early hydration. Modeling that, a time- and temperature-dependent model for the evolution of early-age material parameters, such as stiffness, is derived. The model employs the maturity method, using an equivalent time to capture the temperature influence. It is verified using experimental data on stiffness evolution from squeeze flow tests and yield stress evolution measured from rotational rheometer tests. The model parameters are estimated using Bayesian inference, and validation shows good agreement with experimental data for both parameters at the material level. Subsequently, the derived time- and temperature-dependent stiffness model is adapted into a structural simulation using an elastoplastic material law with nonlinear hardening to study the temperature effect on the stability of 3DCP. Layers are activated sequentially based on a pseudo-density approach. The method is illustrated with an example of a printed wall with a width of one layer under varying ambient temperatures. The temperature impact on buckling and material failure during printing is demonstrated and numerically investigated through a sensitivity study. T2 - 95 th Annual Meeting of the International Association of Applied Mathematics and Mechanics (GAMM) CY - Poznan, Poland DA - 07.04.2025 KW - 3D concrete printing KW - Structural build-up KW - Temperature KW - Maturity method KW - Structural simulation PY - 2025 AN - OPUS4-62966 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Baensch, Franziska A1 - Baer, Wolfram A1 - Chruscicki, Sebastian A1 - Homann, Tobias A1 - Prager, Jens A1 - Schmidt, Dirk A1 - Stajanca, Pavol A1 - Weltschev, Margit A1 - Wossidlo, Peter A1 - Habib, Abdel Karim T1 - AGIFAMOR: Anwendung der verteilten akustischen und faseroptischen Sensorik zur kontinuierlichen Überwachung von Rohrleitungen - Teil 2: Technische Hintergründe - Schadensursachen und Prüfeinrichtungen N2 - Schäden an Rohrleitungen können zu hohen Umweltbelastungen und wirtschaftlichen Schäden führen. Um die dauerhafte Verfügbarkeit der Infrastruktur zu gewährleisten, wird im Rahmen des Projekts AGIFAMOR an der Bundesanstalt für Materialforschung und -prüfung (BAM) erprobt, inwiefern das Verfahren der verteilten akustischen faseroptischen Sensorik (Distributed acoustic sensing – DAS) zur kontinuierlichen Überwachung von Rohrleitungen eingesetzt werden kann. Neben der DAS werden erprobte Verfahren der zerstörungsfreien Prüfung wie Schallemissionsanalyse (SEA) und Beschleunigungssensoren eingesetzt. An dieser Stelle soll detailliert auf die Hauptschadensursachen an Rohrleitungen, den Versuchsstand zur mechanischen Belastung von Rohren sowie die Möglichkeiten zu Untersuchungen im Realmaßstab eingegangen werden. KW - Schadensursachen an Rohrleitungen KW - Monitoring von Rohrleitungen KW - Verteilte Faseroptische Sensorik KW - Rohrbiegeprüfstand KW - Leckage PY - 2018 SN - 2191-0073 VL - 8 IS - 3 SP - 24 EP - 29 PB - Springer VDI-Verlag GmbH & Co. KG CY - Düsseldorf AN - OPUS4-44507 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Poli, Marco A1 - Grätz, Rainer A1 - Schröder, Volkmar T1 - An experimental study on safety-relevant parameters of turbulent gas explosion venting at elevated initial pressure N2 - The effects of a gas explosion in enclosures like vessels can be limited e.g. by gas explosion venting systems. The major design step of this constructive explosion protection method is to determine the required vent area, which depends significantly on whether turbulent combustion exists. However, current standards like NFPA 68 or EN 14994 are applicable only to limited boundary conditions and as far as possible only to laminar flame propagation. Difficulties arise in the assessment or predictability of gas explosion hazard when turbulence occurs. In this research especially venting at elevated initial pressure has been shown to accelerated flame propagations and therefore, to a considerably higher reduced pressure. Therefore, it is essential to provide a broader data base of turbulent combustion and explosion behavior to verify the existing rules or to determine their safety-relevant parameters. For a better safety assessment or design of protective systems the turbulent combustion and accelerated gas explosion behaviour of quiescent methane and hydrogen in air were investigated at initial pressures up to 8 bar using vessels up to 100 litres. In particular a systematic study was performed to investigate the influence of turbulence on the overpressure development during accelerated gas explosion. Moreover, the present study consider the position of the spark igniters, the burning velocity and the maximum pressure rise for different concentration of fuel as well as the size of orifice and/or vent area. A choice of experimental tests showed under the investigated conditions that not only turbulence inducing obstacles but also over sized vent areas could lead to an increased pressure development and therefore to an inacceptable safety state. T2 - 20th International Congress of Chemical and Process Engineering CHISA 2012 CY - Prague, Czech Republic DA - 25.08.2012 KW - Gas explosion venting KW - Turbulent combustion KW - Obstacles PY - 2012 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-264288 DO - https://doi.org/10.1016/j.proeng.2012.07.398 SN - 1877-7058 VL - 42 SP - 90 EP - 99 PB - Elsevier CY - Amsterdam AN - OPUS4-26428 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Strangfeld, Christoph T1 - Introduction of a monitoring system for Bingham fluids in additive manufacturing with concrete N2 - Freeform additive manufacturing of concrete structures is a rising technology in civil engineering with several fascinating advantages. Nonetheless, to ensure reliability and structural integrity, standards and quality control are required in the future to bring this technology into the market. As the concrete is manufactured continuously, continuous quality control of the printing process is also required, i.e. comprehensive process monitoring. At BAM, a test rig will be installed, enabling the printing of concrete structures with a maximum size of 2 m x 1 m x 1 m (l x w x h). Here, process monitoring is the focus of the test rig. In this study, we show the results of the first pump tests, including the measurement of several parameters such as temperature and pressure along the supply system, i.e. from the concrete pump to the printer head. T2 - NDT-CE 2022 CY - Zurich, Switzerland DA - 16.08.2022 KW - Additive manufacturing of concrete KW - Process monitoring KW - Non-destructive testing KW - Bingham fluid PY - 2022 AN - OPUS4-55637 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Baensch, Franziska T1 - Acoustic emission testing N2 - The phenomenon of acoustic emission (AE) and fundamentals of AE testing procedures are presented. AE based failure analysis of reinforced concrete beam under bending load, steel pipe segments under bending load and wood based materials under tension load are discussed. T2 - INFRASTAR, Training Week #03 at AAU CY - Aalborg, Denmark DA - 04.06.2018 KW - Acoustic emission PY - 2018 AN - OPUS4-45147 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Baensch, Franziska A1 - Hussels, Maria-Teresa A1 - Chruscicki, Sebastian A1 - Baer, Wolfram A1 - Wossidlo, Peter A1 - Homann, Tobias A1 - Prager, Jens A1 - Schmidt, Dirk A1 - Weltschev, Margit A1 - Habib, Abdel Karim T1 - AGIFAMOR: Anwendung der verteilten akustischen und faseroptischen Sensorik zur kontinuierlichen Überwachung von Rohrleitungen - Teil 1: Projektvorstellung und erste Vorversuche N2 - In der Prozessindustrie werden häufig gefährliche Stoffe eingesetzt, so dass auch kleinste Leckagen der medienführenden Anlagenteile zu Gefährdungen der Arbeitnehmer sowie zur Belastung der Umwelt führen können. Für die Gewährleistung einer dauerhaften Verfügbarkeit der Infrastruktur ist die frühzeitige Erkennung und Ortung von potentiell gefährlichen Veränderungen an den Wandungen von Rohrleitungen und Behältern (in Form von Rissen, Pittings und Ablagerungen) erforderlich. Am Beispiel von Rohrleitungen, sollen im Rahmen des Projekts AGIFAMOR an der Bundesanstalt für Materialforschung und -prüfung (BAM), im Sinne einer Machbarkeitsstudie die Verfahren der verteilten akustischen und faseroptischen Sensorik zur kontinuierlichen Überwachung und Detektion potentiell gefährlicher Veränderungen in Industrieanlagen erprobt und qualifiziert werden. Dabei sollen die Applikation der optischen Sensorfasern hinsichtlich der Signalübertragung auf den Sensor optimiert und die Erkennung der für dieses Anwendungsgebiet relevanten Schallsignaturen entwickelt werden. Mithilfe eines solchen Messsystems können mit geringem Aufwand ausgedehnte Strukturen, auch unter erschwerten Bedingungen (z.B. hohe Temperatur, Einfluss von Chemikalien) kontinuierlich überwacht werden. KW - Beschleunigungssensoren KW - Faseroptische Sensorik KW - Schallemission KW - Monitoring KW - Rohrleitung PY - 2017 SN - 2191-0073 VL - 7 IS - 3 SP - 10 EP - 16 PB - Springer VDI-Verlag GmbH & Co. KG CY - Düsseldorf AN - OPUS4-40183 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Baensch, Franziska T1 - Non-threshold acoustic emission analysis of damage evolution in pipe segments of steel S355J2H under bending load N2 - Four-point bending tests were carried out to analyze the acoustic characteristics of damage development in pipe segments made of steel, grade S355J2H, being 2.5 m long with an outer diameter of 168 mm and 16 mm wall thickness. To induce stable crack growth, the pipe segments were pre-damaged by a 90°circumferential notch in the middle of the pipe length. While the pipe was quasi-statically loaded, microscopic damage and plastic deformation accumulated to form a macroscopic crack that grew through the pipe wall until leakage. For acoustic emission (AE) monitoring, four broadband sensors of type VS 900 M were mounted close to the notch. Continuous AE signal detection was performed by the non-threshold method. Advantages and disadvantages of the non-threshold AE monitoring compared to a commonly employed method analyzing only signals exceeding a predefined threshold are discussed. The results of AE analysis are compared to additional information on the crack growth detected by the direct current potential drop (DCPD) technique. These studies were carried out in the course of the interdisciplinary research project AGIFAMOR, Ageing infrastructures - distributed acoustic monitoring of pipes at BAM. T2 - 33rd European Conference on Acoustic Emission Testing CY - Senlis, France DA - 12.09.2018 KW - Crack growth KW - Crack initiation KW - Four-point bending test KW - Steel pipe KW - Acoustic emission PY - 2018 AN - OPUS4-45964 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schmidt, Wolfram A1 - Rübner, Katrin A1 - Schneider, Joachim A1 - von Werder, Julia A1 - Gluth, Gregor T1 - 63. DAfStb-Forschungskolloquium in der BAM - Themenblock 2: Nachhaltigkeitspotentiale N2 - Die Bauindustrie ist für rd. 40 % des weltweiten Energieverbrauchs und der Kohlenstoffemissionen verantwortlich. Mit der technologischen Entwicklung wird der Energiebedarf in Zukunft sinken, während sich das Problem grauer Emission verschärft. Daher ist ein verantwortungsvoller Umgang mit Ressourcen der Schlüssel zur Erreichung der Pariser Klimaziele. Der Einsatz klimaschonender Baustoffe weist dabei ein erhebliches Nachhaltigkeitspotential auf. Recycling, Rückgewinnung, Ressourcenschonung und Kreislaufwirtschaft können zu unersetzlichen Bestandteilen der Bautechnik werden. Im Folgenden werden einige Möglichkeiten vorgestellt, die bei der Dekarbonisierung der Bautechnik zukünftig hohe Potentiale aufweisen. Diese wurden beim 63. Forschungskolloquium des DAfStb an der BAM vorgestellt und Details können dem Tagungsband (DOI 10.26272/opus4-61338) entnommen werden. T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM Green Intelligent Building CY - Berlin, Germany DA - 16.10.2024 KW - Bindemittel KW - Klimaschonende Baustoffe KW - Dekarbonisierung PY - 2025 SN - 0005-9846 VL - 75 IS - 4 SP - 131 EP - 134 PB - concrete content UG CY - Schermbeck AN - OPUS4-63068 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hüsken, Götz A1 - Strangfeld, Christoph A1 - Robens-Radermacher, Annika A1 - von Werder, Julia A1 - Weigel, Sandra A1 - Mezhov, Alexander T1 - 63. DAfStb-Forschungskolloquium in der BAM - Themenblock 3: Innovative Technologien N2 - Innovationen sind der Treiber des technologischen Fortschritts. Durch die Anwendung innovativer Technologien, Produktionsverfahren und neuer Materialien können Effizienzsteigerungen erzielt werden, die sowohl zu einer Kosten- als auch Materialreduzierung führen können. Gerade vor dem Hintergrund einer nachhaltigen Entwicklung sind Innovationen der Schlüssel zu einem verantwortungsvollen Umgang mit Ressourcen und Rohstoffen. Im Rahmen des 63. DAfStb-Forschungskolloquiums (Tagungsband: DOI 10.26272/opus4-61338) an der BAM wurden innovative Ansätze im Bereich effizienter Fertigungstechnologien und neuer Materialien vorgestellt, die nachfolgend kurz zusammengefasst werden. T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM Green Intelligent Building CY - Berlin, Germany DA - 16.10.2024 KW - Additive Fertigung KW - Biorezeptive Oberflächen KW - Biopolymere PY - 2025 SN - 0005-9846 VL - 75 IS - 4 SP - 134 EP - 135 PB - concrete content UG CY - Schermbeck AN - OPUS4-63069 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Baensch, Franziska T1 - Feasibility study: Continuous monitoring of pipes using distributed acoustic and fibre optic sensors N2 - The feasibility study „AGIFAMOR. Ageing infrastructures – distributed acoustic monitoring of pipes” is an interdisciplinary research project at BAM internally financed from 2015 to 2018. Therefore, the quite young fibre optic sensing technology of distributed acoustic sensing (DAS) was investigated to possibly be extended towards a global condition monitoring system for pipelines operating in real time. DAS is a highly dynamic fibre optic sensing technology based on the method of coherent optical time domain reflectometry (C-OTDR). DAS allows capturing strain changes in the range of kHz. For the experimental work, the most suitable application yielding an optimum sensitivity was proven by wrapping a standard single-mode silica fibre around the pipe. The DAS sensitivity was investigated regarding the detection of 1) incidents that initiate propagation of acoustic waves in the pipe wall, 2) changes inside the pipeline causing altered flow and 3) damage development in the pipe wall. Therefore, several testing setups in laboratory as well as in real scale were realized. For comparison purposes, experiments were accompanied by acoustic emission analyses and by measurements with accelerometers. DAS was found to be very sensitive to gas ignition and its propagation across the pipe. Furthermore, the ability of DAS to detect and localize acoustic signals associated with pipeline leakage was demonstrated. The detection of crack formation and propagation within the pipe wall by means of DAS was studied during bending tests on several pipe segments, but was not proven so far with certainty. As expected, these studies turned out as the most difficult challenge due to the random occurrence and transient nature of microscopic damage phenomena. T2 - International Symposium on Structural Health Monitoring and Nondestructive Testing CY - Saarbrücken, Germany DA - 04.10.2018 KW - Fibre optic acoustic sensing KW - Continous monitoring KW - Acoustic emission KW - Accelerometers KW - Bending tests on pipe segments KW - Leak detection PY - 2018 AN - OPUS4-46200 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - INPR A1 - Andrés Arcones, Daniel A1 - Weiser, M. A1 - Koutsourelakis, P-S. A1 - Unger, Jörg F. T1 - Embedded Model Bias Quantification with Measurement Noise for Bayesian Model Calibration N2 - A key factor in ensuring the accuracy of computer simulations that model physical systems is the proper calibration of their parameters based on real-world observations or experimental data. Inevitably, uncertainties arise, and Bayesian methods provide a robust framework for quantifying and propagating these uncertainties to model predictions. Nevertheless, Bayesian methods paired with inexact models usually produce predictions unable to represent the observed datapoints. Additionally, the quantified uncertainties of these overconfident models cannot be propagated to other Quantities of Interest (QoIs) reliably. A promising solution involves embedding a model inadequacy term in the inference parameters, allowing the quantified model form uncertainty to influence non-observed QoIs. This paper introduces a more interpretable framework for embedding the model inadequacy compared to existing methods. To overcome the limitations of current approaches, we adapt the existing likelihood models to properly account for noise in the measurements and propose two new formulations designed to address their shortcomings. Moreover, we evaluate the performance of this inadequacy-embedding approach in the presence of discrepancies between measurements and model predictions, including noise and outliers. Particular attention is given to how the uncertainty associated with the model inadequacy term propagates to the QoIs, enabling a more comprehensive statistical analysis of prediction’s reliability. Finally, the proposed approach is applied to estimate the uncertainty in the predicted heat flux from a transient thermal simulation using temperature observations. KW - Model bias KW - Bayesian inference KW - Noise KW - Model updating KW - Quantity of Interest PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-652720 DO - https://doi.org/10.48550/arXiv.2410.12037 SP - 1 EP - 37 PB - arXiv.org AN - OPUS4-65272 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - INPR A1 - Villani, P. A1 - Andés-Arcones, Daniel A1 - Unger, Jörg F. A1 - Weiser, M. T1 - Posterior sampling with Adaptive Gaussian Processes in Bayesian parameter identification N2 - Posterior sampling by Monte Carlo methods provides a more comprehensive solution approach to inverse problems than computing point estimates such as the maximum posterior using optimization methods, at the expense of usually requiring many more evaluations of the forward model. Replacing computationally expensive forward models by fast surrogate models is an attractive option. However, computing the simulated training data for building a sufficiently accurate surrogate model can be computationally expensive in itself, leading to the design of computer experiments problem of finding evaluation points and accuracies such that the highest accuracy is obtained given a fixed computational budget. Here, we consider a fully adaptive greedy approach to this problem. Using Gaussian process regression as surrogate, samples are drawn from the available posterior approximation while designs are incrementally defined by solving a sequence of optimization problems for evaluation accuracy and positions. The selection of training designs is tailored towards representing the posterior to be sampled as good as possible, while the interleaved sampling steps discard old inaccurate samples in favor of new, more accurate ones. Numerical results show a significant reduction of the computational effort compared to just position-adaptive and static designs. KW - Adaptive Gaussian Processes KW - Bayesian parameter identification KW - AGP PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-652731 DO - https://doi.org/10.48550/arXiv.2411.17858 SP - 1 EP - 23 PB - arXiv.org AN - OPUS4-65273 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Unger, Jörg F. T1 - Methodological Prerequisites for Reliable Simulation Results in the Virtual Lab and Digital Twins N2 - Simulationen übernehmen zunehmend eine zentrale Rolle in sicherheitskritischen Entscheidungsprozessen, etwa im Bauwesen, bei digitalen Zwillingen oder in der prädiktiven Instandhaltung. Damit diese Entscheidungen auf zuverlässigen numerischen Modellen basieren können, müssen die zugrunde liegenden Teilmodelle eindeutig beschrieben, reproduzierbar und in der Community validiert sein. Dieses Manuskript skizziert die notwendigen Voraussetzungen für vertrauenswürdige, FAIR-konforme und entscheidungsfähige Simulationsprozesse. Zunächst wird die Notwendigkeit einer formalen, softwareunabhängigen Beschreibung mathematischer Modelle und numerischer Implementierungen diskutiert. Standards wie VMAP, Ontologien wie MathModDB sowie BIM- und STEP-Formate bieten erste Ansätze zur semantischen Modellbeschreibung und zur automatisierten Generierung simulationsfähiger Eingabedaten. Im zweiten Teil wird die Rolle experimenteller Daten für die Validierung von Modellen beleuchtet. Es wird gezeigt, dass hochwertige, strukturierte und maschinenlesbare Validierungsdatensätze essenziell sind, insbesondere für die Bewertung konstitutiver Modelle. Ein weiteres Kapitel widmet sich der Unsicherheitsquantifizierung. Neben klassischen Fehlermaßen werden aleatorische und epistemische Unsicherheiten sowie deren Einfluss auf die Modellbewertung behandelt. Besondere Aufmerksamkeit gilt der Bayes’schen Kalibrierung, der Trennung von Trainings und Testdaten und der Notwendigkeit, auch Begleitversuche aus Materialtests zu dokumentieren. Abschließend wird die Idee einer Benchmarking-Plattform vorgestellt, die auf reproduzierbaren Workflows, automatisierter Provenienzverfolgung und der Nutzung von Research Object (RO) Crates basiert. Diese Plattform erlaubt die dezentrale Veröffentlichung und zentrale Abfrage von Benchmark-Ergebnissen und fördert eine gemeinschaftliche Verifikation und Validierung. Ziel ist es, die Vergleichbarkeit von (Open-Source-)Simulationstools zu verbessern um dadurch komplexe experimentelle Setups zunehmend durch zuverlässige Simulationen ersetzen zu können. T2 - NAFEMS - Symbiose von Simulation und Test CY - Wiesbaden, Germany DA - 12.11.2025 KW - Verification and Validation, KW - Digital twins KW - Virtual lab KW - Uncertainty quantification PY - 2025 SN - 978-1-83979-242-7 SP - 23 EP - 28 PB - NAFEMS CY - Wiesbaden, Germany AN - OPUS4-65271 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Neumann, Patrick P. A1 - Kohlhoff, Harald A1 - Hüllmann, Dino A1 - Kluge, Martin A1 - Askar, Enis A1 - Habib, Abdel Karim A1 - Krentel, Daniel A1 - Mair, Georg W. A1 - Rudolph, Michael A1 - Schoppa, André A1 - Szczepaniak, Mariusz A1 - Storm, Sven-Uwe A1 - Tschirschwitz, Rico T1 - Auswirkungen von Behälterversagen bei alternativen PKW-Antrieben - Teil 2: UAV-basierte Fernerkundung von Gaswolken N2 - Verkehrsunfälle unter Beteiligung von Fahrzeugen mit alternativen Kraftstoffen wie LPG („Autogas“, Liquefied Petroleum Gas), CNG (Compressed Natural Gas, komprimiertes Erdgas) oder CGH2 (Compressed Gas Hydrogen, komprimierter Wasserstoff), bergen neue, komplexe Risiken für Passagiere, Einsatzkräfte und deren Umfeld. Im Rahmen des Projektes „CoFi-ABV“ beschäftigt sich die Bundesanstalt für Materialforschung und -prüfung (BAM) unter Berücksichtigung komplexer Brand- und Explosionsszenarien mit einer ganzheitlichen Betrachtung der Auswirkungen des unfallbedingten Versagens von Gasbehältern für alternative Kraftstoffe. Ein wichtiger Teil des Forschungsvorhabens umfasst Entwicklung, Aufbau und Validierung einer unbemannten Flugplattform (Unmanned Aerial Vehicle, UAV) zur Ferndetektion von Gaswolken. Für das sogenannte gassensitive Mini-UAV wird ein robuster Open-Path-Gasdetektor auf einer Sensorbewegungsplattform in Form eines modifizierten Kamera-Gimbals, integriert. Ziel ist es, ein leistungsfähiges und robustes Werkzeug zu entwickeln, welches Einsatzkräften im Falle eines Unfalls als Hilfe zur Abschätzung der Gefahr durch Gaswolken, ihrer Ausbreitung und der notwendigen Absperrbereiche zur Verfügung steht. Dieser Artikel ist der zweite der Reihe und legt, nach Projektvorstellung im ersten Teil, nun den Schwerpunkt auf das gassensitive Mini-UAV. KW - UAV KW - Fernerkundung KW - Open-Path-Gasdetektor KW - Alternative Antriebe/Kraftstoffe KW - Behälterversagen PY - 2016 SN - 2191-0073 VL - 6 IS - 11/12 SP - 23 EP - 28 PB - Springer-VDI-Verlag CY - Düsseldorf AN - OPUS4-38517 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CHAP A1 - Hofmann-Böllinghaus, Anja ED - Vogdt, F. U. T1 - Brandschutz N2 - Grundlagen des vorbeugenden baulichen Brandschutzes KW - Brandprüfungen KW - Bauvorschriften PY - 2022 SN - 978-3-8348-2189-8 SP - 199 EP - 220 PB - Springer ET - 1 AN - OPUS4-54317 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Georg, Paul A1 - Block, R. A1 - Heister, W. A1 - Holl, S. A1 - Pulm, A. A1 - Hofmann-Böllinghaus, Anja T1 - A score regarding the need for assistance - considering pedestrians with impairments in evacuation planning N2 - The capabilities of pedestrians for evacuation have a significant impact on the time required to reach a safe place. Usually, the evacuation is split into two main stages: pre-movement-phase and movement-phase. For both a large number of studies investigate different representations of behaviour and impacts. But the influence of impairments is usually not taken into account. In addition, most of the scientific researches focus the investigation of the movement phase. This publication presents a novel approach to score the need for assistance and to estimate the effect on evacuation performance. The proposed score considers characteristic impairments in three dimensions of behaviour: reception, perception and realisation. In an unannounced evacuation training in a sheltered workshop, the evacuation behaviour and pre-movement phase were analysed. The analysis indicates that the pre-movement time depends on the kind of impairment as well as on organisational boundaries. Despite the special needs for assistance, the evacuation process in a sheltered workshop is quite similar to other sub-populations. T2 - 5. Magdeburger Brand- und Explosionsschutztage 2017 CY - Magdeburg, Germany DA - 23.03.2017 KW - Human behaviour KW - Human factors KW - Egress KW - Evacuation KW - Persons with impairments PY - 2017 SN - 978-3-00-056201-3 DO - https://doi.org/10.978.300/0562013 SP - 1 EP - 13 CY - Magdeburg AN - OPUS4-40051 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Krentel, Daniel A1 - Tschirschwitz, Rico A1 - Kluge, Martin A1 - Askar, Enis A1 - Habib, Abdel Karim A1 - Kohlhoff, Harald A1 - Neumann, Patrick P. A1 - Rudolph, Michael A1 - Schoppa, André A1 - Storm, Sven-Uwe A1 - Szczepaniak, Mariusz T1 - Experimental investigation of failure of LPG gas tanks in passenger cars during full fire development N2 - In continuation of a preceding test series involving sole LPG vehicle tanks, three passenger cars equipped with identical toroidal steel LPG tanks were set on fire. The tanks were installed in the space normally reserved for the spare tyre, in the car boot. No safety device was installed on the tank, in order to force critical failure of the cylinder. Two of the cars were equipped with a tank filled with liquefied propane to a level of 20 % (5.3 kg), the third one was filled completely (25.5 kg). The partially filled tanks failed critically within a time period of more than 20 min after the initiation of the fire. The fully-filled tank did not rupture; the propane was released continuously through a small leak that appeared during the fire. Comprehensive equipment was used to procure measurement data, enabling an analysis of potential consequences and hazards to humans and infrastructure within the vehicle surroundings. The inner status of the tank (pressure, temperature of the liquid phase and the steel casing), the development of the fire (temperature inside and around the vehicle) and the pressure induced in the near-field in case of tank rupture were recorded. The results were analysed in detail and compared against the data gained in tests involving sole, but identical LPG tanks. T2 - FIVE 2018 CY - Boras, Sweden DA - 03.10.2018 KW - Behälterversagen KW - LPG KW - Alternative Antriebe KW - Fahrzeugbrand KW - Auswirkungsbetrachtung PY - 2018 SN - 978-91-88695-95-6 VL - 51 SP - 123 EP - 131 PB - RISE Safety CY - Boras AN - OPUS4-46310 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR ED - Hofmann-Böllinghaus, Anja ED - Anderson, J. T1 - Special issue: Facade fire safety N2 - Façade fires are of growing concern worldwide. Severe facade fires in different parts of the world as well as activities in many countries regarding the testing of facades show the urgency of the fire safety challenges in façade fires. The need for knowledge and a wide Archive of work in this area has become evident after recent incidents which involved extensive facade fires. These include the tragic fires in Dubai and Grenfell Tower in 2017 in the United Kingdom. In many cases, the widespread live news coverage of the events and size of These fires has emphasized the need for progress in the understanding of the processes involved in these fires and put pressure upon the fire safety engineering community to find effective solutions. KW - Testing KW - Safety PY - 2021 UR - https://onlinelibrary.wiley.com/toc/10991018/2021/45/5 SN - 0308–0501 SN - 1099-1018 VL - 45 IS - 5 SP - 583 EP - 696 PB - Wiley CY - Oxford AN - OPUS4-53102 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR ED - Hofmann-Böllinghaus, Anja ED - van Hees, P. T1 - Special Issue on Facade Fire Safety N2 - This Special Issue of Fire and Materials brings together a Collection of papers that were presented at the 2016 Interflam conference in the Fire & Facades session along with recent submissions to the Fire and Materials Journal that are very relevant to the Fire and Facades subject. Having attended the Interflam conference, all Fire and Materials Journal editors who attended realised the importance of this topic. We felt it important that this session content would both be reviewed and made available to a wider audience and that it was timely that we featured this increasing important topic in our journal. Accordingly, authors of selected papers were invited to update and extend their papers for journal submission, and other appropriate peer review papers subsequently submitted to the journal were included in the collection. KW - Editorial PY - 2018 SN - 0308–0501 VL - 42 IS - 5 SP - 463 EP - 577 PB - Wiley CY - London AN - OPUS4-53104 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Krentel, Daniel A1 - Rudolph, Michael A1 - Tschirschwitz, Rico A1 - Kluge, Martin A1 - Askar, Enis A1 - Habib, Abdel Karim A1 - Kohlhoff, Harald A1 - Neumann, Patrick P. A1 - Schalau, Bernd A1 - Schoppa, André A1 - Storm, Sven-Uwe A1 - Szczepaniak, Mariusz A1 - Mair, Georg W. T1 - Infrared radiation measurement at failure of mobile gas vessels N2 - 15 identical off-the-shelf propane cylinders (m = 11 kg liquid propane) were underfired. The infrared Radiation of the Explosion, that occurred in the aftermath of the vessel failure, was recorded using four bolometers. These measurements are compared with an estimation of the Maximum intensity gained by an Analysis of the Video data, an Extended Version of the Stefan-Boltzmann law and a BLEVE model. T2 - 26th International Colloquium on the Dynamics of Explosions and Reactive Systems CY - Boston, USA DA - 30.07.2017 KW - Failure of gas vessels KW - Propane cylinder KW - Gas explosion KW - Consequences KW - Infrared radiation PY - 2017 SP - 1 EP - 6 PB - FM Global CY - Seattle, USA AN - OPUS4-41993 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Robens-Radermacher, Annika T1 - Modellierung und Simulation von 3D Betondruck – Design- und Prozessoptimierung N2 - Der 3D Betondruck ermöglicht die effiziente und ressourcenschonendere Herstellung maßgeschneiderter Betonstrukturen. Trotz des großen Potentials gibt es bisher keine einheitlichen Normen und Standards für den sicheren und robusten 3D Betondruck. Der Beitrag zeigt das Potential numerischer Methoden und Modelle zur effizienten und ressourcenschonenden Design- und Prozessoptimierung des 3D Betondrucks. Dazu werden die aktuellen Forschungsarbeiten im Bereich der Entwicklung robuster und zuverlässiger numerischer Zwillinge, geeigneter Optimierungstools sowie digitaler Workflows diskutiert. T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM Green Intelligent Building CY - Berlin, Germany DA - 16.10.2024 KW - 3D Betondruck KW - Design- und Prozessoptimierung KW - Modellierung KW - Simulation PY - 2024 AN - OPUS4-61575 LA - mul AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hussels, Maria-Teresa T1 - Faseroptische Pipelineüberwachung N2 - Rohrleitungssysteme sind aufgrund ihrer Funktion und Länge hinsichtlich der Sicherheit, Verfügbarkeit und Instandhaltung in Anlagen besonders relevant. Große Fördermengen führen dazu, dass auch kleinste Leckagen hohe Umweltbelastungen verursachen können. Die frühzeitige Erkennung und Ortung von potentiell gefährlichen Veränderungen am Rohr (z.B. Risse, Pittings, Ablagerungen) ist daher erforderlich. In vielen Fällen ist jedoch die Ausstattung einer Rohrleitung mit einer großen Zahl diskreter Sensoren nicht möglich oder sinnvoll. Die Verfahren der verteilten faseroptischen Sensorik ermöglichen den Einsatz einer einzigen optischen Faser, die gleichzeitig als örtlich kontinuierlicher Sensor sowie zur Signalübertragung genutzt wird, so dass mit vergleichsweise geringem Installationsaufwand sehr ausgedehnte Strukturen mit Sensoren ausgestattet werden können. Im Monitoring von Öl- und Gaspipelines befindet sich daher die verteilte faseroptische Sensorik derzeit im Aufwind. Neben den Verfahren zur Messung von Temperatur und Dehnung ist zuletzt speziell die verteilte faseroptische akustische Sensorik (distributed acoustic sensing, DAS) in den Vordergrund gerückt, da sie u.a. mechanische Einwirkungen Dritter auf die Pipeline (Annäherung, Graben, Manipulation) erfassen kann. Das Potential von DAS zur kontinuierlichen Zustandsüberwachung einer Rohrleitung durch die Erkennung und Ortung von Schallereignissen, die auf eine Schädigung schließen lassen, wird derzeit im Rahmen eines interdisziplinären Forschungsprojektes an der BAM untersucht. Zur Qualifizierung der Methode in diesem Anwendungsbereich werden insbesondere Fragestellungen zur Sensorapplikation in Hinblick auf optimale Signalübertragung und Praktikabilität sowie zur Sensitivität des Messsystems und auch der Erfassung und Erkennung der relevanten Schallsignaturen bearbeitet. T2 - Pipeline Symposium 2016 CY - Hamburg, Germany DA - 23.11.2016 KW - Verteilte faseroptische Sensorik KW - Verteilte akustische Sensorik KW - Pipelinemonitoring PY - 2016 AN - OPUS4-38453 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Gaal, Mate A1 - Wernicke, Pascal A1 - Hufschläger, Daniel T1 - Pulse compression for air-coupled ferroelectret and thermoacoustic transducers N2 - The main advantage of air-coupled ultrasonic testing is the absence of a liquid couplant, which can damage some materials. However, most air-coupled testing scenarios have the challenge of low signals and a signal-to-noise ratio (SNR) several orders of magnitude lower than with couplant-assisted tech-niques. Since this challenge of small SNR also exists in radar technology, the pulse compression used there was adapted and applied to the physical conditions of air-coupled ultrasonic testing. This paper presents ultrasonic transmission measurements on a carbon-fibre-reinforced polymer plate using two experimental setups: 1) a thermoacoustic transmitter and an optical microphone and 2) a pair of ferroe-lectret transducers as transmitter and receiver. Thermoacoustic transmitters convert electrical energy to heat, which causes the air to expand thus producing acoustic waves. The optical microphone is based on a Fabry-Perot interferometer. Ferroelectrets are charged cellular polymers, having piezoelectric proper-ties and excellent acoustic matching to air. Both thermoacoustic transmitters and ferroelectrets are non-linear regarding the relationship between the excited sound pressure and the excitation voltage. Due to these physical boundary conditions, unipolar coding was used to modulate the excitation signals. Vari-ous codes were tested, and parameters of the excitation pulses were varied to find the optimal combina-tion for each experimental setup. The application of pulse compression to the combination of thermo-acoustic transmitter and optical microphone increased the signal-to-noise ratio by up to 16 dB and for the ferroelectret transducers by up to 23 dB. T2 - 30th International Congress on Sound and Vibration CY - Amsterdam, The Netherlands DA - 08.07.2024 KW - Pulse compression KW - Air-coupled ultrasonic transducers KW - Ferroelectret KW - Thermoacoustics PY - 2024 SN - 978-90-90-39058-1 SP - 1 EP - 7 AN - OPUS4-60725 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz T1 - Reduction of ground-induced building vibrations by kinematic and inertial soil-structure interac-tion and by base isolation N2 - Many buildings on the soil have been measured and the transfer function freefield-to-building is ana-lysed. In general, an amplification at low frequencies, an amplification for the floor resonances, and a reduction for higher frequencies can be observed. Most of the measurement examples show a flexible behaviour along the height of the buildings. The prediction of building vibration consists typically of three steps. At first, the dynamic stiffness of the foundation and secondly the kinematic soil-structure interaction has to be calculated for example by the combined finite-element boundary-element meth-od. The stiffness of the foundation reduces the incoming waves (the kinematic interaction). Finally, the inertial interaction of the building with the foundation soil is calculated by the conventional finite ele-ment method where the dynamic foundation stiffness from the first step is added at the bottom of the building. The building on the compliant soil has a fundamental vertical resonance usually below 10 Hz. A parametrical variation clearly shows the influence of the elasticity of the building on this reso-nance frequency and amplitude. Moreover for column-type office buildings, the low-frequency floor resonances can further reduce this fundamental frequency. A 1-dimensional model has been estab-lished which can well approximate the behaviour of the 3-dimensional building models. It is used to demonstrate the effect of a base isolation with soft elements at the foundation. A rigid building model clearly over-estimates the isolation effect, which is smaller for a model with flexible walls, columns and floors. An even simpler model of an infinitely high building is suggested for the mitigation effect, and the resonance frequency of the rigid building should be replaced by a better performance indica-tor, which is based on the impedance ratio of the isolation and the wall and which can be also ex-pressed as a characteristic frequency. T2 - 30th International Congress on Sound and Vibration CY - Amsterdam, Netherlands DA - 08.07.2024 KW - Building vibrations KW - Base isolation KW - Foundation stiffness KW - Kinematic soil-structure interaction KW - Transfer functions of flexible buildings PY - 2024 SN - 978-90-90-39058-1 SN - 2329-3675 SP - 1 EP - 8 AN - OPUS4-61245 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Baensch, Franziska T1 - BAM-Projekt AGIFAMOR – Zustandsüberwachung von Rohrleitungen N2 - Rohrleitungssysteme sind aufgrund ihrer Funktion und Ausdehnung für den Betrieb, die Verfügbarkeit und die Sicherheit von Industrieanlagen von besonderer Bedeutung. Die bisher in definierten Intervallen durchgeführten, wiederkehrenden Prüfungen zur Sicherstellung leckagefreier Rohrleitungen sind kostenintensiv und mit einem erhöhten Aufwand verbunden. Mit dem interdisziplinären Forschungsprojekt AGIFAMOR (Ageing Infrastructures – Akustisches Monitoring von Rohrleitungen) arbeitet die BAM an der Entwicklung und Erprobung einer örtlich und zeitlich kontinuierlichen Zustandsüberwachung von Rohrleitungen basierend auf einem faseroptischen akustischen Messsystem, welches einen vergleichsweise geringen Installationsaufwand der Sensoren erfordert. Mit diesem Verfahren sollen vor allem betriebsbedingte Schädigungen infolge von Korrosion sowie daraus entstehende Pittings oder Risse erkannt und damit Leckagen verhindert werden. Im Rahmen einer Machbarkeitsstudie zum Teilaspekt „Detektion von Risswachstum“ wurde ein 2,5 m langes, definiert vorgekerbtes Stahlrohr mit der faseroptischen Sensorik (FOS) ausgestattet und quasistatisch unter 4-Punkt-Biegung belastet. Mit fortschreitender Belastung wächst, ausgehend vom vorhandenen Außenumfangskerb, ein Riss im Stahlrohr bis zum Erreichen der Leckage – in der Praxis ein gefährliches Schadensszenario. Parallel zur FOS erfolgten Messungen mit Schallemissionssensoren, Beschleunigungssensoren und Potentialsonden, deren Ergebnisse die Interpretation der FOS-Messergebnisse unterstützen sollen. T2 - 21. Kolloquium Schallemission CY - Fulda, Germany DA - 09.03.2017 KW - Beschleunigungssensoren KW - Faseroptische Sensorik KW - Schallemission KW - Monitoring KW - Rohrleitung PY - 2017 AN - OPUS4-40182 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kang, Chongjie A1 - Arcones, Daniel Andrés A1 - Becks, Henrik A1 - Beetz, Jakob A1 - Blankenbach, Jörg A1 - Claßen, Martin A1 - Degener, Sebastian A1 - Eisermann, Cedric A1 - Göbels, Anne A1 - Hegger, Josef A1 - Hermann, Ralf A1 - Kähler, Philipp A1 - Peralta, Patricia A1 - Petryna, Yuri A1 - Schnellenbach‐Held, Martina A1 - Schulz, Oliver A1 - Smarsly, Kay A1 - Fatih Sönmez, Mehmet A1 - Sprenger, Bjarne A1 - Unger, Jörg F. A1 - Vassilev, Hristo A1 - Weiser, Martin A1 - Marx, Steffen T1 - Intelligente digitale Methoden zur Verlängerung der Nutzungsdauer der Nibelungenbrücke N2 - Um die Lebensdauer von Bauwerken unter Wahrung derer Standsicherheit und Funktionsfähigkeit zu verlängern, bedarf es effektiver Monitorings‐ sowie Instandhaltungskonzepte. Im Rahmen des von der Deutschen Forschungsgemeinschaft (DFG) geförderten Schwerpunktprogramms 2388 „Hundert plus – Verlängerung der Lebensdauer komplexer Baustrukturen durch intelligente Digitalisierung“ (kurz: SPP 100+) werden hierfür innovative, interdisziplinäre Methoden entwickelt und an der Nibelungenbrücke in Worms (NBW) validiert. Der vorliegende Beitrag stellt einige dieser neuentwickelten digitalen Methoden vor. Unter anderem umfasst dies zwei Systeme des Structural Health Monitoring (SHM) und deren zielorientierte Verknüpfung von mehreren Beschleunigungsmessdaten zur umfassenden Zustandsbewertung. Ergänzend werden innovative datenbasierte Simulationsmethoden zur Bestimmung des Temperaturfelds des Brückenüberbaus vorgestellt sowie mehrere Finite‐Elemente‐Modelle unterschiedlicher Detailtiefe präsentiert und miteinander verglichen. Abschließend werden innovative Methoden zum Verwalten des Bestandswissens von Brückenbauwerken diskutiert. Die Methoden wurden überwiegend unabhängig voneinander entwickelt und an der NBW validiert. Im nächsten Schritt werden die Methoden integriert, um die Instandhaltung der NBW zu unterstützen. KW - Nibelungenbrücke Worms KW - Digitaler Zwilling KW - Prädiktive Instandhaltung KW - Bauwerksmonitoring KW - Nachrechnung KW - Verkehrsinfrastruktur KW - FE-Modell PY - 2025 DO - https://doi.org/10.1002/best.70070 SN - 0005-9900 VL - 121. Jahrgang 2026 SP - 1 EP - 18 PB - Ernst & Sohn a Wiley Brand CY - Wien, Austria AN - OPUS4-65288 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Recknagel, Christoph A1 - Engel, Philipp T1 - SensoJointField - Konzeption einer Online-Messstation zur Deformationserfassung im Fugenbereich hochbeanspruchter Betonverkehrsflächen N2 - Im Rahme eines Forschungsauftrages des Bundeministeriums für Verkehr wurde ein autonomes Sensornetzwerk "SensoJoint" für den Feldeinsatz im hochbeanspruchten Bundesfernstraßenbereich entwickelt. Grundlage ist der 3-axiale Deformationssensor "SensoJoint" der BAM, der im Verbund mit weiteren Sensoren (z.B. WIM-Sensorik) ein intelligentes und - im Zusammenhang mit einem modernen Energiemanagement - autarkes Monitoring-System bildet. Der Beitrag gibt einen Überblick zum Stand des F&E-Projektes. KW - Performance Konzept KW - Infrastruktur KW - Hochbeanspruchte Betonfahrbahndecken KW - Fugenproblematik PY - 2025 DO - https://doi.org/10.53184/STA12-2025-1 SN - 0039-2162 VL - 76 IS - 12 SP - 895 EP - 899 PB - Kirschbaum-Verlag CY - Bonn AN - OPUS4-65301 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Strangfeld, Christoph A1 - Ringeloth, David T1 - Zustandserfassung von Spannbetonschwellen mittels akustischer Methoden N2 - Unterseitige oder innenliegende Risse bzw. Gefügeschäden in Spannbetonschwellen können durch Sichtprüfung häufig nicht festgestellt werden. Mit zerstörungsfreien Prüfverfahren werden diese Schäden und deren räumliche Ausdehnung visualisiert und einer quantitativen Analyse unterzogen. Das Ultraschallverfahren kann zusätzlich die Tiefenlage von Rissen innerhalb der Schwellen feststellen. Auch das Impakt-Echo-Verfahren zeigt im Signalbild eine klare Abhängigkeit vom Schwellenzustand. Durch eine neuartige luftgekoppelte Signalanregung, die keinen mechanischen Kontakt zur Oberfläche benötigt, kann dieses Verfahren auf Prüfzügen bei hohen Fahrgeschwindigkeiten eingesetzt werden. KW - Spannbetonschwellen KW - Ultraschall KW - Impakt-Echo KW - Zustandsbewertung PY - 2026 IS - 01 SP - 45 EP - 49 PB - DVV Media Group GmbH | Eurailpress CY - Hamburg AN - OPUS4-65307 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kocherla, Amarteja A1 - Strangfeld, Christoph A1 - Hüsken, Götz T1 - Embedded Sensors for Quality Control and Structural Integrity Monitoring of Large-scale 3DCP Structures N2 - In extrusion-based 3D concrete printing (3DCP), addressing challenges related to safety, reliability, and quality control is crucial for widespread adoption. Yet current limitations in monitoring material properties during and after printing hinder the development of effective 3DCP guidelines. Therefore, the development of an inline sensing system capable of real-time monitoring and adjustment of process parameters is necessary to overcome these challenges. Building upon an existing inline sensing system developed by BAM, which currently monitors material properties during printing and the geometry of the print post-extrusion, this study extends its capabilities to post-extrusion monitoring using embedded piezoelectric (PZT) sensors. These PZT sensors provide localized measurements of material changes through electrical impedance (EI) measurements without disrupting the printing process. By embedding these sensors in 3D printed structures, continuous monitoring is achieved from layer deposition through 1-day of hydration. To achieve this, initially, PZT sensors were developed with multiple layers of protective coatings. Two different 3D printed mixtures, each with different hydration behaviors, were utilized, and PZT sensors were strategically placed between printed layers to maintain their integrity. EI measurements were collected continuously from printing through 1 day of hydration. Analysis of amplitude and frequency changes in the EI response spectrum provided insights into material behavior post-printing. The study highlights how continuous monitoring of frequency and conductance can track structural builtup and property development of the material. Rapid changes in conductance measurements, immediately post-printing indicate swift structural built-up, while key hydration phases are reflected in frequency measurements. T2 - 34th Annual Conference and Exhibition on Non Destructive Evaluation & Enabling Technologies CY - Chennai, India DA - 12.12.2024 KW - Embedded Sensors KW - 3D Concrete Printing KW - Quality Control KW - Inline Sensing KW - Structural Integrity PY - 2025 SP - 1 EP - 8 PB - Springer Nature CY - Heidelberg AN - OPUS4-65305 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Stohl, Leonie A1 - Manninger, Tanja A1 - Dehn, Frank A1 - von Werder, Julia T1 - Understanding bioreceptivity of concrete: material design and characterization N2 - The climate crisis is driving an increasing demand for ecologically oriented concepts. In the building sector, this demand includes not only the use of environmentally friendly materials but also the greening of urban areas. One promising approach is the development of bioreceptive concrete façades, which support the growth of green biofilms directly on their surfaces. These innovative façades are anticipated to deliver benefits comparable to those of macroscopically greened façades, such as enhanced biodiversity and improved air quality, while offering the advantages of being more self-sustaining and stable systems once fully established. However, the development of bioreceptive concrete presents substantial challenges. Due to the interdisciplinarity and novelty of this field, standardized methods for material characterization and bioreceptivity assessment are currently lacking. This study proposes an approach for evaluating surface properties crucial for bioreceptivity, developed on differently structured samples of ultra-high-performance concrete (UHPC). Existing methods and standards from concrete technology are critically reviewed and, where necessary, modified to meet the unique requirements of measuring bioreceptive material properties. Special attention is given to the surface pH value and water retention characteristics, as these are essential for promoting microbial growth and ensuring the long-term stability of green biofilms. The observed surface characteristics vary according to the imprinted surface structures, offering a spectrum of material properties and enabling the evaluation of their impact on bioreceptivity. The findings presented form the foundation for subsequent laboratory weathering experiments, which will be discussed in a complementary publication. KW - Bioreceptivity KW - Concrete KW - Biofilm PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-648180 DO - https://doi.org/10.1617/s11527-025-02863-y SN - 1359-5997 VL - 58 IS - 10 SP - 1 EP - 12 PB - Springer Science and Business Media LLC AN - OPUS4-64818 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - von Werder, Julia T1 - Biorezeptivität und Optimierung von Lehmbaustoffen - Forschung an der BAM N2 - Der Vortrag fasst die Forschungsaktivitäten der BAM in den Themengebieten Biorezeptivität von Beton und Optimierung von Lehmbaustoffen zusammen. Er diente als Kurzpräsentation für eine anschließende Podiumsdiskussion. T2 - Transformationsdialog "Material als Motor" CY - Berlin, Germany DA - 10.10.2024 KW - Biorezeptivität KW - Beton KW - Lehmbaustoffe PY - 2024 AN - OPUS4-62220 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - von Werder, Julia T1 - Living Concrete Walls: Engineering Bioreceptivity and Biofilms N2 - Building envelopes are a natural habitat of subaerial biofilms and can be more or less prone to be colonized (i.e. to be bioreceptive). Focusing on the added value of biofilms on manmade substrates represents new aesthetic frontiers and reduces the use of biocides. Moreover, the metabolic processes of photosynthetic biofilms can positively influence human health and life quality in densely populated cities by converting or absorbing pollutants. In the presented research the bioreceptivity of concrete claddings for building facades is engineered to sustain either natural or artificial establishment of microalgae-dominated biofilms. To be able to differentiate between the intrinsic material properties and the climatic boundary conditions, the experimental design in the first step comprised different analyses with model mono- and multi-species biofilms in sterile conditions and a high control of the environmental parameters. Growth and vitality of the algal component of the biofilms has been assessed with Pulse-amplitude modulation (PAM) fluorometry. T2 - 78th RILEM Annual Week & RILEM International Conference on Sustainable Materials & Structures: Meeting the major challenges of the 21st century - SMS 2024 CY - Toulouse, France DA - 25.08.2024 KW - Bioreceptivity KW - Biofilm KW - Weathering KW - Concrete KW - PAM fluorometry KW - Carbonation PY - 2024 AN - OPUS4-62224 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - THES A1 - Schlick-Hasper, Eva T1 - Analyse, Charakterisierung und Modellierung der Gasleckageraten repräsentativer Bauarten von Gefahrgutverpackungen N2 - Derzeit existieren für Gefahrgutverpackungen in den internationalen Gefahrgutvorschriften keine Festlegungen für quantitative Grenzleckageraten, die sich an Sicherheitsbetrachtungen während der Beförderung orientieren. Für die Dichtheitsprüfung im Rahmen der Bauartzulassung von Gefahrgutverpackungen für flüssige Füllgüter ist das Standardprüfverfahren das Eintauchverfahren in Wasser („Bubble Test“). Hierbei handelt es sich um ein lokalisierendes Prüfverfahren. Seine Anwendung lässt keine quantitative Aussage darüber zu, ob unter Beförderungsbedingungen aufgrund von strömungsbedingter Stofffreisetzung durch Leckstellen der Gefahrgutverpackungen die Gefahr der Bildung einer explosionsfähigen Atmosphäre besteht. Zentrales Ziel der vorliegenden Arbeit ist daher, zunächst quantitative Dichtheitsanforderungen an Gefahrgutverpackungen im Hinblick auf die Entstehung explosionsfähiger Dampf-Luft-Gemische während des Transports zu entwickeln. Im Anschluss werden strömungsbedingte Leckageraten der Verschlüsse verschiedener Bauarten von Gefahrgutverpackungen gemessen. Der Vergleich der Messwerte mit den berechneten Grenzwerten ermöglicht die Einschätzung hinsichtlich der Bildung einer explosionsfähigen Atmosphäre. Dieser quantitative Ansatz zur Beurteilung der Dichtheit ist für Gefahrgutverpackungen derzeit noch nicht etabliert. Die Grenzleckageraten werden für das Szenario des interkontinentalen Transports von Gefahrgutverpackungen in einem 20-Fuß-Frachtcontainer im Hinblick auf die untere Explosionsgrenze abgeleitet. Dies geschieht unter Annahme einer Worst-Case-Betrachtung für Beförderungsdauer, Beladung und Luftwechselrate. Als mittlere Beförderungstemperatur wird 30 °C angesetzt. Eine vollständige Durchmischung im freien Luftraum des Containers wird angenommen. Es werden drei repräsentative Baugrößen von Gefahrgutverpackungen gewählt, mit einem Volumen von ca. 6 L, ca. 60 L und ca. 220 L. Als Füllgüter werden die 23 meistbeförderten flüssigen Gefahrgüter betrachtet. Die treibende Kraft für die Strömung durch Leckstellen ist der sich in der Verpackung ausbildende Überdruck. Die Berechnung des Überdrucks erfolgt durch analytische Modellgleichungen in Abhängigkeit der spezifischen Stoffdaten, Füllgrad, Befülltemperatur, Transporttemperatur und Nachgiebigkeit der Verpackungsbauart. Die quantitative Leckageratenmessung der Gefahrgutverpackungen wird mit dem Überdruckverfahren mit Ansammlung (Akkumulationsverfahren) unter Verwendung von Helium als Prüfgas vorgenommen. Zusätzlich erfolgt die Detektion weiterer potentieller Leckstellen außerhalb des Verschlussbereiches mit dem Schnüffelverfahren. Bei allen untersuchten Bauarten, mit Ausnahme des 6 L-Feinstblechkanisters, ist der Verschluss die einzige systematische Leckstelle der Verpackung. Die Messung der Helium-Leckageraten und der anschließende Vergleich mit den berechneten Helium-Grenzleckageraten zeigt, dass folgende Bauarten hinsichtlich des Erreichens der unteren Explosionsgrenze (UEG) durch eine Leckageströmung als kritisch einzuschätzen sind: Kunststoffverpackungen mit Schraubverschlüssen mit Flachdichtung, wenn bei diesen bestimmte Schädigungsmuster im Verschlussbereich vorliegen; Feinstblechkanister, da bei ihnen nicht nur der Verschlussbereich eine Leckstelle darstellt; Kunststoffverpackungen mit Schraubverschlüssen mit Flachdichtung, wenn diese auch für Füllgüter der Verpackungsgruppe I zugelassen sind. Als Konsequenz sollten bei diesen kritischen Bauarten entweder Modifikationen in Bezug auf die Verpackung selbst oder auf die Transportbedingungen im Frachtcontainer vorgenommen werden. Bei Kunststoffverpackungen ist auch die Füllgutpermeation als Freisetzungsmechanismus relevant. Es wird der prinzipielle Rechenweg zur Berücksichtigung dieses Quellterms exemplarisch gezeigt. Diese Arbeit leistet einen grundlegenden Beitrag für die Etablierung einer systematischen quantitativen Dichtheitsbetrachtung von Gefahrgutverpackungen mit dem Ziel der Verbesserung der Sicherheit beim interkontinentalen Gefahrguttransport im Frachtcontainer. T3 - BAM Dissertationsreihe - 161 KW - Gefahrgutverpackungen KW - Dichtheit KW - Dichtheitsprüfung KW - Leckagerate KW - Überdruck KW - Dangerous goods packagings KW - Leakproofness KW - Leak testing KW - Leakage rate KW - Gauge pressure PY - 2018 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-468410 SN - 1613-4249 VL - 161 SP - 1 EP - 244 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-46841 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schartel, Bernhard T1 - Phosphorus-based flame retardancy mechanisms - Old hat or a starting point for future development? N2 - Different kinds of additive and reactive flame retardants containing phosphorus are increasingly successful as halogen-free alternatives for various polymeric materials and applications. Phosphorus can act in the condensed phase by enhancing charring, yielding intumescence, or through inorganic glass formation; and in the gas phase through flame inhibition. Occurrence and efficiency depend, not only on the flame retardant itself, but also on its interaction with pyrolysing polymeric material and additives. Flame retardancy is sensitive to modification of the flame retardant, the use of synergists/adjuvants, and changes to the polymeric material. A detailed understanding facilitates the launch of tailored and targeted development. KW - Fire retardancy KW - Red phosphorus KW - Phosphate KW - Phosphonate KW - Phosphinate KW - Phosphine oxide KW - Flame inhibition KW - Charring KW - Intumescence PY - 2010 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-220368 DO - https://doi.org/10.3390/ma3104710 SN - 1996-1944 VL - 3 IS - 10 SP - 4710 EP - 4745 PB - MDPI CY - Basel AN - OPUS4-22036 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kruschwitz, Sabine T1 - Feuchtemessung im Bauwesen - Ein Überblick N2 - Ein Großteil der Schäden im Baubereich ist auf feuchteinduzierte Prozesse zurückzuführen. Der Erhaltungsaufwand allein im Hochbau wurde bereits vor einiger Zeit auf jährlich ca. 35 Mrd. Euro geschätzt. Aus diesem Grund hat die Feuchtemessung in der Bauwerksdiagnose eine sehr hohe Bedeutung - und im Idealfall sollte sie natürlich alles können: schnell sein, wiederholbar und zerstörungsfrei anwendbar. Zwar gibt es eine Vielzahl an verfügbaren Feuchtemesstechniken, oft fällt es Anwendern aber schwer, einzuschätzen welches die richtige Prüfmethode für ihr Problem ist. Genormt sind nur direkte und zerstörende Verfahren, die zwar teils hochgenau, aber doch nur stichprobenartig Aussagen liefern können. Die anderen, zerstörungsfreien Methoden basieren auf der Änderung feuchteabhängiger physikalischer Materialeigenschaften. Ihre Grundlagen, sowie Vor- und Nachteile werden hier näher dargestellt. T2 - Fachtagung Bauwerksdiagnose 2014 CY - Berlin, Germany DA - 13.02.2014 KW - Feuchtemessung KW - Zerstörungsfreie Prüfung KW - Baustoffe PY - 2014 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-311672 UR - http://www.bauwerksdiagnose2014.de/portals/bwd2014/BB/vortrag%205.pdf UR - http://www.bauwerksdiagnose2014.de/Berichtsband SN - 978-3-940283-56-6 SP - 1 EP - 8 PB - Deutsche Gesellschaft für Zerstörungsfreie Prüfung (DGZfP) CY - Berlin AN - OPUS4-31167 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Luong, Thi Mai Hoa A1 - Zabel, V. A1 - Lorenz, W., A1 - Rohrmann, R.G., T1 - Vibration-based model updating and identification of multiple axial forces in truss structures N2 - Safety assessment of existing iron and steel truss structures requires the determination of the axial Forces and corresponding stresses in truss structural members. The results of the axial force determination can be integrated as part of a structural health Monitoring scheme for existing trusses. In this work, a methodology is proposed to identify multiple axial forces in members of a truss structure based on the modal parameters. Vibration test allows the identification of the natural frequencies and mode shapes, globally of the truss structure as well as locally of the individual bars. The method calibrates the numerical model of the truss structure using a genetic algorithm and strategic validation criteria. The validation criteria are based on the identified natural frequencies and global mode shapes of the truss structure as well as information of the axial forces in the individual bars of the truss, which are estimated from the natural frequencies and five amplitudes of the corresponding local mode shapes of the single bars based on an analytical-based algorithm. The calibration allows the identification of the axial forces in all bars of the truss structure. For mode pairing strategy, a technique makes use of the enhanced modal assurance criteria with the calculation of the modal strain energies. Moreover, the modal strain energies are also used to select the relevant local mode shape of the individual bars. The feasibility and accuracy of the proposed methodology is verified by laboratory experiments on several truss structures. In situ tests on existing trusses are intended. The results from one of the laboratory tested structures, i.e. a two-bar system, are included in this paper. KW - Truss structures KW - Axial force KW - Dynamic test KW - Model updating KW - Optimization technique PY - 2017 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-402263 DO - https://doi.org/10.1016/j.proeng.2017.04.499 SN - 1877-7058 VL - 188 SP - 385 EP - 392 PB - Elsevier AN - OPUS4-40226 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Lexow, Jürgen T1 - Industrial safety - Public demand and an answer of BAM the federal German institute for materials research and testing N2 - Safe industrial operation is expected by the public. It contributes to a clean environment, innovation and prosperity. BAM the Federal German Institute for Materials Research and Testing has its responsibility in further developing safety in technology and chemistry by research, testing and expert advice. The basic reasoning for this activity and examples of current work are provided. Particular attention is given to the unique BAM Test site Technical Safety. Acceptance of fi ndings and transfer of results are based on collaboration and exchange of personal. Modes of cooperation are described. KW - Industrial safety KW - Large test fecility KW - Structural integrity KW - Dangerous substance PY - 2014 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-322519 DO - https://doi.org/10.2478/tvsbses-2014-0010 SN - 1805-3238 VL - 9 IS - 2 SP - 40 EP - 45 PB - VSB - Sborník vedeckých prací Vysoké Skoly Bánské - Technické Univerzity Ostrava CY - Ostrava AN - OPUS4-32251 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kolkoori, Sanjeevareddy A1 - Wrobel, Norma A1 - Deresch, Andreas A1 - Redmer, Bernhard A1 - Ewert, Uwe T1 - Dual high-energy X-ray digital radiography for material discrimination in cargo containers N2 - In this contribution, we present a dual high-energy X-ray imaging technique for cargo container inspection using the 'spectral high-energy X-ray attenuation method'. This method is based on attenuation of continuous highenergy spectra. The developed experimental technique consists of a betatron as high-energy (up to 7.5 MeV) X-ray source and a matrix detector with high spatial resolution (400 ìm) for digital X-ray imaging. In order to evaluate the material discrimination capability using dual high-energy X-ray imaging, a test specimen is proposed, comprising step wedges of different low and high atomic number (Z) materials. The selected X-ray spectra for the dual-energy experiments correspond to 3 MV and 7.5 MV acceleration potential of the betatron. We evaluated the ratio between low- and high-energy X-ray attenuation coefficients quantitatively based on simulated poly-energetic high-energy X-ray source spectra and the detector sensitivity using the 'analytical Radiographic Testing inspection simulation tool' (aRTist) developed at BAM. The simulated effective attenuation coefficients are compared with corresponding experimental results in order to establish a method for identification of low- and high-Z materials in the container. Finally, important applications of the proposed technique in the context of aviation security are discussed. T2 - ECNDT 2014 - 11th European conference on non-destructive testing CY - Prague, Czech Republic DA - 06.10.2014 KW - Digital radiography KW - NDT KW - High-energy X-ray imaging KW - Betatron KW - Digital detector array (DDA) KW - Container inspection KW - Material discrimination KW - Effective attenuation coefficient PY - 2014 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-322394 UR - https://www.ndt.net/?id=16430 SN - 1435-4934 VL - 19 IS - 12 SP - 1 EP - 10 PB - NDT.net CY - Kirchwald AN - OPUS4-32239 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wrobel, Norma A1 - Kolkoori, Sanjeevareddy A1 - Zscherpel, Uwe A1 - Ewert, Uwe T1 - Innovative X-ray backscatter technique for security applications: Detection of dangerous materials N2 - Radiological inspections, in general, are NDT&E methods to detect the bulk of explosives without invasion into the object of analysis. In contrast to personal luggage, cargo or structural components constitute a complexity that may significantly hamper the detection of a threat by conventional transmission radiography. A novel approach of interrogating a large object to a certain depth only with a single sided access will be presented. It consists of an X-ray backscatter camera with a special twisted slit collimator for imaging backscattered objects. The new X-ray backscatter camera is not only imaging the objects due to their densities but also by taking into account the influences of surrounding objects. Additionally, it does not only image illuminated features but also depicts shadows from absorbing materials. This is a unique characteristic of the developed X-ray backscatter camera. Experimental mock-ups are conducted imitating container with threats among a complex packing as they may be encountered in reality. At the end, the significant advantages of the presented X-ray backscatter camera in the context of aviation and port security will be discussed. T2 - ECNDT 2014 - 11th European conference on non-destructive testing CY - Prague, Czech Republic DA - 06.10.2014 KW - Radiography KW - X-ray backscatter imaging KW - Irradiation geometry KW - Detection of dangerous materials KW - Security applications PY - 2014 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-322429 UR - https://www.ndt.net/?id=16432 SN - 1435-4934 VL - 19 IS - 12 SP - 1 EP - 8 PB - NDT.net CY - Kirchwald AN - OPUS4-32242 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kolkoori, Sanjeevareddy A1 - Wrobel, Norma A1 - Zscherpel, Uwe A1 - Ewert, Uwe T1 - New X-ray backscatter imaging technique for nondestructive testing of aerospace components N2 - Critical parts in aircraft manufacturing such as stringers are very commonly used in modern aircraft structures to resist the compressive loads caused by the aerodynamic effects. They are generally made-up of thin aluminium (Al) metal sheets and are one of the key components in the aircraft wings. Any defects in the stringer leads to weakening of the stiffness of the whole wing structure and consequently, failures may occur. Hence, the structural integrity of the stringers should be evaluated using reliable non-destructive testing (NDT) methods. Due to the complex shaped structure of the stringer, the one-sided access NDT method such as X-ray backscatter technique is more preferable for the non-destructive imaging. In this paper, we present a new X-ray backscatter technique to image the internal sections of the stringer with only a single-sided access. The whole object was inspected by changing the viewing direction of the X-ray backscatter camera. For the first time, the X-ray backscatter measurements were conducted using high-energy (> 0.5MeV) X-rays and proved the applicability of the present technique to inspect thick carbon-fiber laminated components. In order to improve the inspection time and image quality of the backscatter image, we used high-resolution (180ìm) digital detector arrays (DDAs). At the end, important applications of the presented X-ray backscatter technique to the aerospace industry are discussed. T2 - ECNDT 2014 - 11th European conference on non-destructive testing CY - Prague, Czech Republic DA - 06.10.2014 KW - X-ray backscatter imaging KW - Twisted-slit collimator KW - NDT KW - Digital detector array (DDA) KW - Stringer KW - Aerospace applications PY - 2014 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-322376 UR - https://www.ndt.net/?id=16431 SN - 1435-4934 VL - 19 IS - 12 SP - 1 EP - 8 PB - NDT.net CY - Kirchwald AN - OPUS4-32237 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kind, Thomas T1 - Ortung von Spanngliedern zum schadensfreien Bohren im Rahmen von Ertüchtigungsmaßnahmen N2 - Am Beispiel der Ertüchtigung einer Brücke in Bremen wird gezeigt, wie mit den zerstörungsfreien Prüfverfahren (ZfP) Radar- und Ultraschall die genau Lage vorgespannte Bewehrung gefunden bzw. bestätigt werden kann. Im Rahmen von Ertüchtigungsmaßnahmen an Spannbetonbrücken werden häufig Kernbohrungen durchgeführt, die die vorhandenen Spannbewehrungen nicht beschädigen dürfen. Es wird die Vorgehensweise beschrieben, wie mit ZfP ein wesentlicher Beitrag geleistet wird, das Risiko einer Beschädigung zu minimieren und somit eine bessere Planungssicherheit für die Ertüchtigungsmaßnahmen zu schaffen. Dabei werden auch die Grenzen der beiden Verfahren aufgezeigt. T2 - Fachtagung Bauwerksdiagnose 2012 - Praktische Anwendungen zerstörungsfreier Prüfungen und Zukunftsaufgaben CY - Berlin, Germany DA - 23.02.2012 KW - Radar KW - Zerstörungsfreie Prüfung KW - Stahlbeton KW - Ultraschall PY - 2012 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-398225 SN - 978-3-940283-40-5 VL - 134 (Vortrag 11) SP - 1 EP - 7 PB - Deutsche Gesellschaft für Zerstörungsfreie Prüfung (DGZfP) CY - Berlin, Germany AN - OPUS4-39822 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kapoor, M. A1 - Overgaard Christensen, Ch. A1 - Wittrup Schmidt, J. A1 - Dalsgaard Sørensen, J. A1 - Thöns, Sebastian T1 - Decision analytic approach for the reclassification of concrete bridges by using elastic limit information from proof loading N2 - Reclassification of bridges, i.e., a change in load rating, using reliability-based methods and a direct update with proof load information has been presented by many authors. However, bridge reclassification has hardly been studied from a decision analytic perspective, i.e., with quantification of the risks and benefits of different classification choices, and the expected benefit gain from proof loading. We derive, explain and exemplify a decision analytic approach for bridge reclassification along with models for (1) elastic and ultimate capacity and their adaptation with proof load information, (2) proof load information with classification outcomes accounting for target reliabilities and, (3) utilities including socio-economic benefits from reclassification. The approach and models are exemplified with a case study based on reclassification of bridges with a low existing classification. Decision rules, for practical use by a highway authority to find the optimal classification, are identified and documented based on: (1) the measurement of the capacity at elastic limit by proof loading, (2) the bridge reclassification benefits, and, (3) the required annual reliability level. From a Value of Information analysis, it is concluded that the proof load information is highly valuable for reclassification in cases of high socio-economic benefits and high reliability requirements. KW - Proof loading KW - Structural reliability KW - Value of information KW - Decision analysis PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-596845 DO - https://doi.org/10.1016/j.ress.2022.109049 SN - 0951-8320/ VL - 232 SP - 1 EP - 16 PB - Elsevier Ltd. AN - OPUS4-59684 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -