TY - CONF A1 - Strobl, Dominic A1 - Robens-Radermacher, Annika A1 - Ghnatios, Ch. A1 - Pittner, Andreas A1 - Rethmeier, Michael A1 - Unger, Jörg F. T1 - Reduced Order Model with Domain Mapping for Temperature Field Simulation of Wire Arc Additive Manufacturing N2 - Additive manufacturing (AM) has revolutionized the manufacturing industry, offering a new paradigm to produce complex geometries and parts with customized properties. Among the different AM techniques, the wire arc additive manufacturing (WAAM) process has gained significant attention due to its high deposition rate and low equipment cost. However, the process is characterized by a complex thermal history, dynamic metallurgy, and mechanical behaviour that make it challenging to simulate it in real-time for online process control and optimization. In this context, a reduced order model (ROM) using the proper generalized decomposition (PGD) method is proposed as a powerful tool to overcome the limitations of conventional numerical methods and enable the real-time simulation of the temperature field of WAAM processes. Though, the simulation of a moving heat source leads to a hardly separable parametric problem, which is handled by applying a novel mapping approach. Using this procedure, it is possible to create a simple separated representation of the model, also allowing to simulate multiple layers. In this contribution, a PGD model is derived for the WAAM procedure simulating the temperature field. A good agreement with a standard finite element method is shown. The reduced model is further used in a stochastic model parameter estimation using Bayesian inference, speeding up calibrations and ultimately leading to a calibrated real-time simulation. T2 - SIM-AM 2023 CY - Munich, Germany DA - 26.07.2023 KW - Additive manufacturing KW - Reduced Order Model PY - 2023 AN - OPUS4-58253 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Strobl, Dominic A1 - Robens-Radermacher, Annika A1 - Ghnatios, C. A1 - Pittner, Andreas A1 - Rethmeier, Michael A1 - Unger, Jörg F. T1 - Reduced Order Model for Temperature Field Simulation of Wire Arc Additive Manufacturing with Domain Mapping N2 - Additive manufacturing (AM) has revolutionized the manufacturing industry, offering a new paradigm to produce complex geometries and parts with customized properties. Among the different AM techniques, the wire arc additive manufacturing (WAAM) process has gained significant attention due to its high deposition rate and low equipment cost. However, the process is characterized by a complex thermal history making it challenging to simulate it in real-time for online process control and optimization. In this context, a reduced order model (ROM) using the proper generalized decomposition (PGD) method [1] is proposed as a powerful tool to overcome the limitations of conventional numerical methods and enable the real-time simulation of the temperature field of WAAM processes. These simulations use a moving heat source leading to a hardly separable parametric problem, which is handled by applying a novel mapping approach [2]. This procedure makes it possible to create a simple separated representation of the model, which allows to simulate multiple layers. In this contribution, a PGD model is derived for the temperature field simulation of the WAAM process. A good agreement with a standard finite element method is shown. The reduced model is further used in a stochastic model parameter estimation using Bayesian inference, speeding up calibrations and ultimately leading to a calibrated real-time simulation. T2 - MORTech 2023 - 6th International Workshop on Model Reduction Techniques CY - Paris, France DA - 22.11.2023 KW - Wire arc additive manufacturing KW - Reduced order modelling PY - 2023 AN - OPUS4-59105 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Strangfeld, Christoph A1 - Stolpe, Heiko A1 - Wiehle, Philipp T1 - Moisture diffusion affected by the Knudsen effect in temporal changing pore networks N2 - Almost all building materials in civil engineering have an open porosity and interact with or are affected by the environmental conditions. Structures might suffer from effects such as moisture adsorption, carbonation, corrosion, penetration of salt ions and chemical substances, etc. In the hygroscopic range, these processes are mostly driven by diffusion. Due to the confinement of small pores ( 1 m), the Knudsen effect reduces the molecular diffusion. This reduction can become more significant in case of temporal changing pore systems because of physisorption of water vapor, carbonation, or chemisorption. In this study, unstabilised earth blocks and earth masonry are investigated. In a first step, the pore size distribution of the blocks is measured and sorption isotherms are recorded in experiments. Besides the ordinary physisorption, the involved clay minerals undergo swelling or shrinking due to chemisorption. The following two effects must be considered: first, the reduction of the available pore space by the adsorbed water layer. For this, the Hillerborg sorption theory is used, which is a combination of the well-known Brunauer-Emmett-Teller sorption theory and the Kelvin equation. This allows the computation of adsorbed water layers even in curved pore geometries. Second, the variation of the initial pore size distribution due to chemisorption needs to be modelled. Based on these two models, the effective diffusion coefficient can be predicted. For validation, arrays of relative humidity sensors were embedded into a free-standing earth masonry wall. This monitoring was carried out over more than a year to have a broad variety of environmental conditions and was located in Berlin, Germany. The prediction of the effective diffusion coefficient can also be transferred to other processes and allows the investigation of materials having temporarily changing pore systems. Examples are the carbonation of cementitious materials, alkali silica reaction, calcium leaching of long-lasting structures, etc. This effect becomes most prominent in the meso-pore range and might alter the effective diffusion coefficient by more than 100 %. T2 - 4th International Congress on Materials & Structural Stability CY - Rabat, Morocco DA - 08.03.2023 KW - Earth masonry KW - Material moisture KW - Molecular diffusion KW - Chemisoprtion KW - Knudsen effect KW - Physisorption PY - 2023 AN - OPUS4-57140 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sperlich, Tim A1 - Häßler, Dustin A1 - Stelzner, Ludwig A1 - Hothan, Sascha T1 - In situ Prüfmethode zur Untersuchung des Feuerwiderstands von bestehenden Stahlkonstruktionen mit reaktivem Brandschutzsystem N2 - Der Beitrag beschreibt die Entwicklung eines neuartigen in situ Nachweisverfahrens zur Beurteilung des Feuerwiderstandes von bestehenden Stahlkonstruktionen mit gealtertem reaktivem Brandschutzsystem (RBS). Derzeit ist ein solcher Nachweis ausschließlich anhand eines Bauteilbrandversuchs möglich. Hierzu muss ein Bauteil aus der Bestandskonstruktion entnommen und einer zerstörenden Brandprüfung unterzogen werden. In Zusammenhang mit der Dauerhaftigkeitsbewertung von RBS für Zeiträume von mehr als 10 Jahren besteht in der Praxis vermehrt der Bedarf an einem minimal invasiven Prüfverfahren, mit dessen Hilfe sich direkt am Bestandsbauwerk die tatsächlich vorhandene Leistungsfähigkeit des gealterten RBS überprüfen lässt. Durch einen erfolgreichen Funktionsnachweis wäre eine Weiternutzung der Bestandkonstruktion bei Aufrechterhaltung des bestehenden Sicherheitsniveaus möglich. T2 - Symposium Heißbemessung - Structural Fire Engineering CY - Braunschweig, Germany DA - 05.09.2023 KW - Brandschutz KW - Stahlbau KW - Reaktives Brandschutzsystem KW - Prüfmethode KW - Brandversuch PY - 2023 AN - OPUS4-58183 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Simon, Patrick T1 - Zustandsbewertung von Bauwerken unter veränderlichen Umgebungsbedingungen mittels Structural Health Monitoring N2 - Brücken sind Teil der alternden Verkehrsinfrastruktur. Um die Nutzungsdauer zu verlängern und plötzliche Schäden zu detektieren kann Bauwerksmonitoring ("Structural Health Monitoring") eingesetzt werden. Der Einfluss von Umgebungsbedingungen, beispielsweise der Temperatur, auf das Bauwerksverhalten ist meist größer als der Einfluss von Schäden. Diese Einflüsse bestmöglich voneinander zu trennen und Veränderungen im Tragverhalten korrekt Schäden oder Umgebungsbedingungen zuzuordnen ist eine offene Forschungsfrage. Diese Arbeit zeigt eine mögliche Lösung, bei der gekoppelte Modelle von Umwelteinflüssen, Schäden und Tragverhalten des Bauwerks auf Grundlage von Monitoringdaten aktualisiert werden. Das Framework dazu wird vorgestellt und an einem Laborexperiment eines Stahlbetonbalkens in der Klimakammer angewandt. Die Ergebnisse bestätigen die Vorgehensweise. In nächsten Schritten müssen komplexere Tragwerke und die Sensitivität des Ansatzes untersucht werden. T2 - Forschungskolloquium, Institut für Konstruktiven Ingenieurbau, Bauhaus-Universität Weimar CY - Weimar, Germany DA - 28.06.2023 KW - Structural health monitoring KW - Bauwerksmonitoring KW - Umwelteinflüsse KW - Brücken PY - 2023 AN - OPUS4-58005 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Seifert, Lando A1 - Burkert, Andreas A1 - Müller, Thoralf A1 - Lehmann, Jens T1 - Grundlagen Korrosion und Korrosionsschutz - Teil 1: Korrosion metallener Werkstoffe N2 - Innerhalb der Fachausbildung "Kathodischer Korrosionsschutz (KKS)" wurde dieser Vortrag im Grundlagenkurs für erdverlegte Anlagen, Stahlbeton und Innenschutz gehalten. Der 90 min Vortrag befasste sich schwerpunktmäßig mit den Grundlagen der elektrochemischen Korrosion von wichtigen Metallen im Bauwesen: Unleg. Stahl, Aluminium- und Zinkwerkstoffen sowie nichtrostenden Stählen. Galvanische Elemente sowie die Grenzen der elektrochemischen Potentialmessung wurden besprochen. Dies wird anhand einer Reihe von Beispielen verdeutlicht. Der Vortag knüpft die Verbindung zwischen den grundlegenden Korrosionsreaktionen, den äußeren Umgebungsbedingungen, der Korrosionsgeschwindigkeit, dem Faraday'schen Gesetz und den elektrochemischen Stromdichte-Potential-Kurven, mit denen in der Korrosionswissenschaft gearbeitet wird. T2 - Grundlagenkurs für erdverlegte Anlagen, Stahlbeton und Innenschutz; Fachausbildung "Kathodischer Korrosionsschutz (KKS)" CY - Online meeting DA - 28.02.2023 KW - Korrosion KW - Elektrochemische Korrosion KW - Potentialmessung KW - Galvanische Korrosion KW - Bimetallkorroison PY - 2023 AN - OPUS4-57068 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Seifert, Lando A1 - Burkert, Andreas A1 - Müller, Thoralf A1 - Lehmann, Jens T1 - Grundlagen Korrosion und Korrosionsschutz - Teil 2: Korrosionsschutz N2 - Im Rahmen der Fachausbildung "Kathodischer Korrosionsschutz (KKS)" fand als Pflichtmodul der Grundlagenkurs für erdverlegte Anlagen, Stahlbeton und Innenschutz statt. Im Vortrag (Teil 2 "Korrosionsschutz") wurden grundlegende Korrosionsschutzmethoden besprochen, welche sich aus dem Wissen über die Grundlagen der Korrosion ergeben. In einem 90 min Vortrag wurden planungs- und werkstoffseitige Vorgehensweisen präsentiert. Der normativ geregelte Korrosionsschutz bietet Regelwerke für verschiedene Umweltbedingungen und Metalle. Anhand einiger Beispiele wurden Normen zur Bestimmung der Korrosivität gezeigt und die Anforderungen an das spezifische Korrosionsschutzsystem erklärt. Schwerpunktmäßig ging es um den Schutz von Metallen in der Atmosphäre, in Erdböden und im Meerwasser. T2 - Grundlagenkurs für erdverlegte Anlagen, Stahlbeton und Innenschutz; Fachausbildung "Kathodischer Korrosionsschutz (KKS)" CY - Online meeting DA - 28.02.2023 KW - Korrosionsschutz KW - Werkstoffauswahl KW - Beschichtungssysteme KW - Deckschichten KW - nichtrostende Stähle KW - Galvanische Anoden KW - Vermeidung der Elementbildung PY - 2023 AN - OPUS4-57069 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Seher, Julia A1 - Rübner, Katrin A1 - Müller, Constanze A1 - Pniok, N. A1 - Dreisow, B. T1 - Leichte Gesteinskörnungen aus Bau- und Abbruchabfällen - Applikation in der Denkmalpflege N2 - Im Rahmen des BMBF-geförderten Forschungsprojekt ReMin - REALight werden in einem Projektteam aus Industriepartnern und Forschungseinrichtungen unter Koordination der Bauhaus-Universität Weimar leichte Gesteinskörnungen aus Bau- und Abbruchabfällen und industriellen Nebenprodukten auf thermischen Weg hergestellt. Die Aufgabe der Bundesanstalt für Materialforschung und -prüfung (BAM) ist es, diese im Drehrohrofen erzeugten Blähgranulate für gebundene Anwendungen in Beton und Mörtel umfassend zu charakterisieren. Gemeinsam mit der Opus Denkmalpflege GmbH wird die Applikation feiner, gebrochener Blähgranulate in leichten Steinergänzungsmörteln für die Restaurierung von Sandsteinobjekten untersucht. Hierzu wird ein zweischichtiges Mörtelsystem bestehend aus Füll- und einem Deckmörtel entwickelt. Erste Ergebnisse der Rezepturentwicklung verschiedener kalkhaltiger Leichtmörtel mit gebrochenen Blähgranulaten werden vorgestellt. Die neuen Leichtmörtel sind hinsichtlich der entwickelten Druckfestigkeit gleichwertig gegenüber herkömmlichen Restauriermörteln. T2 - 21.Internationale Baustofftagung (ibausil) CY - Weimar, Germany DA - 13.09.2023 KW - Leichte Gesteinskörnungen KW - Recycling KW - Denkmalpflege KW - Leichtmörtel PY - 2023 AN - OPUS4-58329 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Seeber, Henrik A1 - Grobert, Steffen A1 - Krentel, Daniel A1 - Kluge, Martin A1 - Hauer, Thorsten T1 - Investigation of intracorporeal shock wave propagation using a simplified torso model and a shock wave generator N2 - Blast injuries are among the most common injuries in military operations. Also, in civilian environments, more explosive threats are expected in the future due to emerging conflicts and threats. While the effect of fragments, which is classified as secondary blast injury, could be minimized by police and military personnel’s modern ballistic body protection systems, the effects of shock wave propagation in the body as part of the primary explosion trauma still remain a serious threat needing further research. The detonation-physical processes of highly dynamic pressure changes within the human body, the reflection-related amplification of shock waves at organ-dermis interfaces, and the consequences of injury mechanisms have become more prominent in international research. Various approaches have been used to investigate these aspects. Animal experiments on free field test sites or shock tube setups combined with a subsequent biological evaluation and numerical simulations provided promising results and allowed the discussion of different biomechanical aspects. However, due to poor reproducibility and a lack of short-term dynamic material properties, most research approaches have significant limitations. Laboratory test setups do not represent real-scale high explosive detonation parameters with regards to pressure characteristics, impulse duration and blockage problems. Measured values are interpreted with partly outdated, selective and not validated limit values for overpressures from field tests with animals. This is due to the lack of a validated and comprehensive data set covering a variation of the crucial parameter. Injury mechanisms and their effects have not yet been sufficiently elucidated for the torso and extremities. In order to contribute to the research efforts on the primary explosion effects, the German Federal Armed Forces established an interdisciplinary military medical research project in cooperation of the Bundeswehr Hospital Berlin and the German Federal Institute for Materials Research and Testing (BAM). The aim of the planned investigation is the development of a multidisciplinary method to investigate shock wave behavior in various generic tissue simulants under the most reproducible conditions possible with realistic loads in an experimental test series with short set-up times. T2 - 7th International Forum on Blast Injury Countermeasures CY - Tokio, Japan DA - 17.05.2023 KW - Shock wave generator KW - Blast injury KW - Primäre Explosionswirkung KW - Experimental setup PY - 2023 AN - OPUS4-60045 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Seeber, Henrik A1 - Grobert, Steffen A1 - Krentel, Daniel A1 - Hauer, Thorsten T1 - Influence of Torso Protective Equipment on Intracorporeal Shock Wave Behavior N2 - In the field of explosive reactions, there is a type of explosive effect that lacks a sufficient database and reproducible experiments regarding biomechanics. It concerns the primary explosive effect. It is defined as pure shock wave of the explosion. The physical behavior of the shock wave when interacting with different types of tissue and, in particular, the subsequent transitions of the shock wave, have barely been investigated. The transition of the shock wave into other materials is the focus of the research Therefore, the aim of the investigations is the development of a multidisciplinary method to investigate shock wave behavior in various generic tissue simulants under the most reproducible conditions possible with realistic loads in an experimental test series with short set-up times. An autoclave is used to generate the pressure waves. A simplified torso model consisting of ballistic gelatin is used as a simulant. In this paper, the influence of protective equipment on the pressure load in the tissue simulant is investigated. For this purpose, consecutive test setups are used. First, the behavior of ballistic gelatin as a tissue simulant is investigated. Then, the simplified torso model is covered with typical combat clothing consisting of four layers. Afterwards a currently used UHMWPE ballistic protective plate is placed in front of the simplified torso model. Finally, the combat clothing and the protective plate are examined in combination. Three cast-in pressure sensors are used as measuring devices, as well as an acceleration sensor attached to the protective plate. The experiments show that the maximum overpressure in a model protected by combat clothing and the protective plate can be reduced by 95%. However, the propagation speed of the shock wave within the simplified torso model increases from 1535.5 m/s to 2204.5 m/s. This shows that even protective equipment, which is not primarily intended to protect against blast, offers a significant reduction in the pressure load in the protected area. On the one hand it is caused by the media transition from air to PE and the resulting higher reflection of the acceleration of the transmitted wave within the simulant. On the other hand, it is also reduced due to the damping and dispersion caused by the clothing layers. T2 - 16th International Personal Armour Systems Symposium CY - Dresden, Germany DA - 11.09.2023 KW - Shock wave generator KW - Blast injury KW - Pressure wave KW - Experimental setup PY - 2023 AN - OPUS4-58639 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Seeber, Henrik A1 - Grobert, Steffen A1 - Krentel, Daniel A1 - Gerbeit, Marco T1 - Experimental Setup for the Reproducible Generation of Pressure Waves in Free Field Conditions N2 - The injuries caused by the primary blast are still poorly understood, especially in the torso region. To generate sufficiently large data sets, shock tubes are often used. However, these have some limitations, such as blockage, use of the exit jet, widening cross-sections, and scaling problems with respect to compressive strength and test objects. Therefore, it is appropriate to conduct experiments under free-field conditions, but tests with real explosives are often associated with long preparation and setup times as well as high safety requirements. Therefore, this paper presents an experimental setup for the reproducible generation of blast waves under free-field conditions. This experimental setup aims to provide a test environment for a sufficiently large specimen to investigate the behaviour of the shock wave within the specimen, especially at the media interfaces. As an example of application, the influence of the primary explosive effect on protective equipment or on tissue simulants for the investigation of blast injuries can be mentioned. An autoclave is used as a shock wave generator. It has a volume of 0.065 m3 and is filled with a stoichiometric acetylene-oxygen gas mixture. The setup and turnaround time is approximately 30 minutes. The following factors have been selected as target variables for the optimization of the shock wave generator: reproducibility of the pressure wave, use-case-relevant positive phase duration and peak overpressure, a pressure curve characteristic corresponding to that of a military explosive under undisturbed free field conditions, and short setup times of the experimental setup. For this purpose, the experimental setup is presented in this paper. Several series of measurements are presented, showing the characteristics of the generated pressure wave. For the generated pressure wave, the classical pressure curve characteristics can be clearly recognized. A peak pressure of 92 kPa is reached at a distance of 1 m from the opening, and the first positive pressure phase lasts 1.17 ms. Furthermore, the pressure wave propagates in a hemispherical shape. The typical characteristics of the blast wave generated by the SWG have been demonstrated using the military explosive PETN. It is shown that the actual load case corresponds to about 70 g of PETN. T2 - 26th International Symposium on Military Aspects of Blast and Shock CY - Wollongong, Australia DA - 03.12.2023 KW - Shock wave generator KW - Blast injury KW - Pressure wave KW - Experimental setup PY - 2023 AN - OPUS4-59356 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schönsee, Eric A1 - Strangfeld, Christoph A1 - Jeyifous, Olubunmi Anthony A1 - Hüsken, Götz A1 - Mezhov, Alexander T1 - Calculating rheological properties of fresh mortar for additive manufacturing based on experimental, multi sensor data N2 - Additive manufacturing of concrete structures is a novel and emerging technology. Free contouring in civil engineering, which allows for entirely new designs, is a significant advantage. In the future, lower construction costs are expected with increased construction speeds and decreasing required materials and workers. However, architects and civil engineers rely on a certain quality of execution to fulfil construction standards. Although several techniques and approaches demonstrate the advantages, quality control during printing is highly challenging and rarely applied. Due to the continuous mixing process commonly used in 3D concrete printing, it is impossible to exclude variations in the dry mixture or water content, and a test sample cannot be taken as a representative sample for the whole structure. Although mortar properties vary only locally, a defect in one layer during printing could affect the entire integrity of the whole structure . Therefore, real-time process monitoring is required to record and document the printing process. At the Bundesanstalt für Materialforschung und -prüfung (BAM) a new test rig for the additive manufacturing of concrete is built. The primary purpose is measuring and monitoring the properties of a mortar during the printing process. The following study investigates an approach for calculating yield stress and plastic viscosity based on experimentally recorded pressure data. The calculations assume that fresh mortar behaves as a Bingham fluid and that the Buckingham-Reiner-equation is applicable. A test setup consisting of rigid pipes with integrated pressure sensors at different positions is utilized. Monitoring the printing process with different sensors is crucial for the quality control of an ongoing process. T2 - Non-Tradijtional Cement and Concrete CY - Brno, Czech Republic DA - 25.06.2023 KW - 3DCP KW - Monitoring KW - Additive Manufacturing KW - Rheology KW - Bingham Fluid PY - 2023 AN - OPUS4-58144 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schulze, Uwe T1 - Measurement of permeation of hydrogen on hoses according to ISO 3821 N2 - The subject of permeation of hoses according to ISO 3821 for hydrogen was discussed for a long time in ISO/TC 44/SC 8. The reason is a considerable leakage of hydrogen diffused into the hose material over the end face of the hose. Because of this unsolved, safety-related problem of hoses sold on the market, measurements should be carried out in order to be able to better assess the problem. BAM has declared its attendance to provide a required fast solution to this issue. T2 - Meeting of the committee ISO/TC 44/SC 8 "Equipment for gas welding, cutting and allied processes" CY - Genoa, Italy DA - 08.11.2023 KW - Permeation KW - Hoses KW - Hydrogen KW - Leakage KW - ISO 3821 PY - 2023 VL - 2023 AN - OPUS4-59375 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schneider, Ronald T1 - Structural integrity management research at BAM N2 - This presentation provides an overview on the structural integrity management research at BAM. In addition, a framework for monitoring and risk-informed inspection and maintenance planning for offshore steel structures is presented. T2 - Structural Health Monitoring Using Statistical Pattern Recognition CY - Berlin, Germany DA - 20.03.2023 KW - Structural integrity KW - Monitoring KW - Maintenance KW - Inspeciton KW - Bridges KW - Offshore wind PY - 2023 AN - OPUS4-57864 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schneider, Ronald A1 - Simon, Patrick A1 - Hille, Falk A1 - Herrmann, Ralf A1 - Baeßler, Matthias T1 - Vibration-based system identification of a large steel box girder bridge N2 - The Bundesanstalt für Materialforschung und -prüfung (BAM) collaborates with TNO to develop a software framework for automated calibration of structural models based on monitoring data. The ultimate goal is to include such models in the asset management process of engineering structures. As a basis for developing the framework, a multi-span road bridge consisting of ten simply supported steel box girders was selected as a test case. Our group measured output-only vibration data from one box girder under ambient conditions. From the data, we determined eigenfrequencies and mode shapes. In parallel, we developed a preliminary structural model of the box girder for the purpose of predicting its modal properties. In this contribution, we provide an overview of the measurement campaign, the operational modal analysis, the structural modeling and qualitatively compare the identified with the predicted modes. As an outlook, we discuss the further steps in the calibration process and future applications of the calibrated model. T2 - XII International Conference on Structural Dynamics (EURODYN 2023) CY - Delft, Netherlands DA - 02.07.2023 KW - Bridge KW - Safety KW - Fatigue KW - Modal system identification KW - Model updating PY - 2023 AN - OPUS4-57863 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schmidt, Martin T1 - Selbstentzündungsverhalten von Holz- und Biokohlen Gefahrguteinstufung sicher? N2 - Mit der Abkehr von der Nutzung fossiler Rohstoffe rücken regenerative Energieträger immer weiter in den Focus. Neben klassischen Holzkohlen werden verstärkt so genannte Biokohlen produziert. Dieser Begriff findet Verwendung für mit Hilfe verschiedener Verfahren karbonisierte pflanzliche, tierische oder mikrobielle Ausgangsstoffe. Diese Kohlen werden zum Teil über weite Strecken zum Bestimmungsort transportiert (Überseetransporte) oder vor Verwendung für längere Zeit gelagert. Häufig zeigen diese Kohlen ein kritisches Selbstentzündungsverhalten, wobei Einstufungstests (UN N.4 Test) versagen können. Ein negatives Testergebnis des UN N.4 Tests führte dabei in der Vergangenheit zur Nichteinstufung als selbsterhitzungsfähiger Stoff; in der Praxis entzündeten sich aber bereits vergleichsweise kleine Schüttungen (einige m³), z. B. beim Seetransport in Containern. Der Artikel geht auf dieses Problem ein, stellt Prüfverfahren vor und gibt Empfehlungen für sicheren Transport und Lagerung. T2 - VDI Fachtagung "Sichere Handhabung brennbarer Stäube CY - Nürnberg, Germany DA - 25.10.2023 KW - Biokohle KW - Selbstentzündung KW - Gefahrguteinstufung PY - 2023 AN - OPUS4-59597 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schmidt, Anita T1 - Certification and approvals of dangerous goods packaging in Germany N2 - Germany and China cooperate in a GIZ project - initiated and supported by the BMDV - in comparing their systems of dangerous goods packagings. T2 - Sino-German Workshop on Dangerous Goods Packaging CY - Online meeting DA - 24.11.2023 KW - Dangerous goods packagings KW - Transport KW - ADR PY - 2023 AN - OPUS4-59276 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schlick-Hasper, Eva A1 - Bethke, John T1 - Vergleichende Schüttwinkelmessungen an festen Gefahrgütern N2 - Die in den von der BAM anerkannten Prüfstellen für Gefahrgutverpackungen gängigen Schüttwinkel-Messmethoden werden verglichen, anhand der Messung an fünf pulverförmigen oder körnigen Stoffen mit gefährlichen Eigenschaften. Zusätzlich wird die Untersuchung des Einflusses einer unterschiedlichen klimatischen Vorlagerung vorgenommen. T2 - 36. Sitzung des BAM AK Prüfstellen CY - Berlin, Germany DA - 12.09.2023 KW - Schüttwinkel KW - Pulver KW - Schüttgüter KW - Fließfähigkeit PY - 2023 AN - OPUS4-58278 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schlick-Hasper, Eva A1 - Bethke, John A1 - Goedecke, Thomas T1 - How To Measure The Angle of Repose of Hazardous Substances in the Test Centers for Dangerous Goods Packagings N2 - The flow properties of powdery or granular filling substances for dangerous goods packagings are safety-relevant parameters. To specify the flow behavior, the angle of repose is measured in the recognized test centers for dangerous goods packagings in Germany. Previous investigations performed on non-hazardous substances revealed that some of the methods currently used have disadvantages in application. Additionally, for occupational health and safety reasons, it was generally viewed critically to carry out measurements of the angle of repose for dangerous goods at all. Instead, the dimensionless Hausner ratio to describe the flow behavior was proposed. In this work, the investigations were extended to real hazardous substances to concretize the assessment. Five exemplary hazardous substances were tested for their angle of repose using the methods commonly applied in the test centers. The Hausner ratio was also determined. In addition, the influence of a different climatic preconditioning on the angle of repose measurement was examined using three selected non-hazardous bulk materials. The results show that the measurement of the angle of repose is not fundamentally excluded for dangerous goods. However, for reasons of applicability, repeatability and occupational health and safety, only the ISO method can be applied for dangerous filling substances. This method provides conservative results regarding a safety-related evaluation of flow properties for the transport of dangerous goods. In principle, both the ISO method and the determination of the Hausner ratio can be used for dangerous goods. It is also essential especially with finely powdered filling goods, to carry out controlled preconditioning. T2 - 31st IAPRI Members' Conference CY - Navi Mumbai, India DA - 22.05.2023 KW - Angle of repose KW - Flow properties KW - Flowability KW - Hausner ratio KW - Powders KW - Sift-proofness PY - 2023 AN - OPUS4-57619 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schepers, Winfried A1 - Kulke, Dennis T1 - Korrelationen zwischen Sondierungen und dynamischen Bodeneigenschaften N2 - Wir zeigen, dass bei homogenen ausgeprägt sandartigen Böden mit statistisch ermittelten Korrelationen die dynamischen Bodensteifigkeiten mit einer Genauigkeit abgeschätzt werden können, die mit der Ungenauigkeit der seismischen Verfahren übereinstimmt. Mit zunehmenden Feinkornanteil werden die Unsicherheiten der statistischen Korrelationen größer. Bei stark überkonsolidierten glazialen Böden sollte von der Anwendung empirischer Korrelationen Abstand genommen werden. T2 - 18. D-A-CH-Tagung für Erdbebeningenieurwesen und Baudynamik CY - Kiel, Germany DA - 14.09.2023 KW - Baugrunddynamik KW - Dynamische Bodenkennwerte KW - Statistische Korrelationen PY - 2023 AN - OPUS4-58581 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -