TY - CONF A1 - Kulkarni, Kajol A1 - Kemmler, Samuel A1 - Schwartz, Anna A1 - Gedik, Gülçin A1 - Chen, Yanxiang A1 - Papageorgiou, Dimitrios A1 - Kavroulakis, Ioannis A1 - Iakymchuk, Roman T1 - Harvesting energy consumption on European HPC systems: Sharing Experience from the CEEC project N2 - Energy efficiency has emerged as a central challenge for modern high-performance computing (HPC) systems, where escalating computational demands and architectural complexity have led to significant energy footprints. This paper presents the collective experience of the EuroHPC JU Center of Excellence in Exascale CFD (CEEC) in measuring, analyzing, and optimizing energy consumption across major European HPC systems. We briefly review key methodologies and tools for energy measurement as well as define metrics for reporting results. Through case studies using representative CFD applications (waLBerla, FLEXI/GALÆXI, Neko, and NekRS), we evaluate energy-to-solution and time-to-solution on diverse architectures, including CPU- and GPU-based partitions of LUMI, MareNostrum5, MeluXina, and JUWELS Booster. Our results highlight the advantages of accelerators and mixed-precision techniques for reducing energy consumption while maintaining computational accuracy. Finally, we advocate the need to facilitate energy measurements on HPC systems in order to raise awareness, teach the community, and take actions toward more sustainable exascale computing. T2 - SCA/HPCAsiaWS 2026: SCA/HPCAsia 2026 Workshops: Supercomputing Asia and International Conference on High Performance Computing in Asia Pacific Region Workshops CY - Osaka , Japan DA - 26.01.2026 KW - Energy consumption KW - eEergy measurement KW - Energy-to-solution KW - Mixed-precision KW - HPC KW - CFD PY - 2026 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-654175 DO - https://doi.org/10.1145/3784828.3785161 SP - 40 EP - 49 PB - ACM CY - New York, NY, USA AN - OPUS4-65417 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Krankenhagen, Rainer A1 - Chaudhuri, Somsubhro A1 - Pittner, Andreas A1 - Winterkorn, Rene A1 - de Finis, Rosa A1 - Palumbo, Davide A1 - Galietti, Umberto T1 - Thermographic investigation of the anisotropic behaviour of additively manufactured AISI316 steel using DED-Arc N2 - Additive manufacturing is one of the most promising techniques for industrial production and maintenance, but the specifics of the layered structure must be considered. The Direct Energy Deposition-Arc process enables relatively high deposition rates, which is favourable for larger components. For this study, specimens with different orientations were prepared from one AISI316 steel block – parallel and orthogonal to the deposition plane. Quasistatic tensile loading tests were carried out, monitored by an infrared camera. The obtained surface temperature maps revealed structural differences between both orientations. The consideration of surface temperature transients yields more details about the behaviour of the material under tensile loading than the conventional stress-strain-curve. These preliminary investigations were supplemented by thermographic fatigue trials. Although the anisotropy was also observed during fatigue loading the fatigue behaviour in general was the same, at least for both inspected specimens. The presented results demonstrate the abilities and the potential of thermographic techniques for tensile tests. T2 - 17th Quantitative Infrared Thermography Conference CY - Bologna, Italy DA - 07.07.2025 KW - Thermoelastic effect KW - Wire-arc-additive manufacturing KW - thermal stress analysis KW - fatigue testing PY - 2026 DO - https://doi.org/10.21611/qirt-2024-029 SP - 1 EP - 8 AN - OPUS4-65372 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Holm, O. A1 - Leube, Peter A1 - Vogel, Christian A1 - Kennedy, E. A1 - Stockenhuber, M. A1 - Lucas, J. A1 - Truong, T. A1 - Rappé, A. A1 - Lu, W. A1 - Blotevogel, J. T1 - Thermische Zerstörung von PFAS in der Sondermüllverbrennung: Einfluss von Temperatur und PFAS-Konzentration N2 - Aufgrund ihrer einzigartigen molekularen Beschaffenheit werden per- und polyfluorierte Alkylsubstanzen (PFAS) in vielen unterschiedlichen Produkten und Anwendungsgebieten eingesetzt. Da sie generell eine hohe Persistenz aufweisen und je nach individueller Struktur unterschiedlich mobil sind, sind sie mittlerweile in allen Umweltkompartimenten und ubiquitär nachzuweisen. Ihre potenzielle (ökologische) Toxizität birgt dabei erhebliche Umweltrisiken, weshalb PFAS in den letzten Jahren mehr und mehr in den Fokus von Umweltverbänden und -behörden gelangten. Gleichzeitig beschäftigen sich Forschungseinrichtungen mit der möglichst weitreichenden Entfernung aus der Umwelt sowie mit deren (anschließender) Zerstörung. Im Projekt ER24-4073 „Untersuchung des thermischen Abbaus von PFAS in einer kommerziellen Großanlage zur Verbrennung gefährlicher Abfälle“, welches vom U.S. Department of Defense (DoD ) über das Strategic Environmental Research and Development Program (SERDP) gefördert wird, untersuchen deutsche, australische und amerikanische Partner die Behandlung von PFAS-haltigen Abfallströmen in einer großtechnischen Verbrennungsanlage, um die Einsatzbereitschaft, Machbarkeit und Sicherheit dieser Zerstörungsmethode zu demonstrieren. T2 - Berliner Konferenz Abfallwirtschaft und Energie CY - Berlin, Germany DA - 28.01.2026 KW - Per- and polyfluoroalkyl substances (PFAS) KW - Verbrennung KW - Kontaminierter Boden PY - 2026 SN - 978-3-911006-65-1 SP - 66 EP - 77 PB - TK Verlag AN - OPUS4-65513 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Duarte, Larissa A1 - Madia, Mauro A1 - Kanna, Naveen A1 - Bär, Jürgen ED - Ricoeur, Andreas T1 - Anwendung der zyklischen R-Kurven-Analyse zur Abschätzung des Kitagawa-Takahashi-Diagramms N2 - Die ausgeprägte Langzeitfestigkeit eines Werkstoffes entspricht der maximalen Spannung, unterhalb derer alle ursprünglich wachstumsfähigen Mikrorisse arretieren. Für fehlerbehaftete Werkstoffe stellt das Kitagawa-Takahashi (KT)-Diagramm die Abhängigkeit der ausgeprägten Langzeitfestigkeit von der Defektgröße dar. Das KT-Diagramm kann mit großem Aufwand experimentell bestimmt oder durch verschiedene Modelle abgeschätzt werden. Solche Ansätze ergeben oft nichtkonservative Prognosen und berücksichtigen weder den Aufbau der Rissschließeffekte noch lokale Spannungen. In dieser Arbeit wird ein Kurzrissmodell auf Grundlage der zyklischen R-Kurve und des Rissarrestphänomens zur Abschätzung des KT-Diagramms vorgestellt. Die Abschätzungen werden mit experimentellen Daten validiert, die mit gekerbten Proben nach dem Treppenstufenverfahren ermittelt wurden. T2 - 57. Tagung des DVM-Arbeitskreises Bruchmechanik und Bauteilsicherheit CY - Köln, Germany DA - 18.02.2025 KW - Langzeitfestigkeit KW - KT-Diagramm KW - zyklische R-Kurven-Analyse PY - 2025 DO - https://doi.org/10.48447/BR-2025-512 VL - 257 SP - 93 EP - 104 PB - Deutscher Verband für Materialforschung und -prüfung e.V. CY - Berlin, Deutschland AN - OPUS4-62603 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Geburtig, Anja A1 - Wachtendorf, Volker A1 - Trubiroha, P. T1 - Simulationsdaten zur photooxidativen Beanspruchung an verschiedenen geografischen Freibewitterungs-Standorten N2 - Freibewitterungen weisen grundsätzlich eine hohe Variabilität der jeweiligen Intensität der Beanspruchungsparameter auf; sie sind nicht einfach wiederholbar. Um dennoch die Ergebnisse einer Beanspruchung vergleichen zu können, ist eine aussagekräftige Charakterisierung der Freibewitterung wichtig. Traditionell werden Daten bekannter Einflussgrößen wie Globalstrahlung, Temperatur oder Feuchtewerte herangezogen. Obwohl man weiß, dass diese Größen an den exponierten Oberflächen wechselwirken und kombiniert als Mikroklima Einfluss auf Degradationsprozesse nehmen, werden schon aus Praktikabilitätsgründen diese separat als klimatische Messgrößen angegeben. Die Aussagekraft dieser Daten ist mäßig. Ziel dieses Beitrags ist es, die Aussagekraft und damit Vergleichbarkeit zu erhöhen, indem diese Messdaten als Stundendaten zu Wirkintegralen vorverarbeitet und jahresweise akkumuliert werden. Betrachtet wird dafür der Prozess der Photooxidation, da dieser Alterungs-mechanismus bei allen Kunststoffen auftritt. Für eine einfache Modellierung wird die wirksame UV-Bestrahlung, gewichtet mit einer Arrhenius-abhängigen Ober¬flächen-temperatur (TOF), über den Beanspruchungszeitraum von hier je einem Jahr akkumuliert. Die Idee einer solchen Messgröße für photooxidative Ober¬flächen¬alterung wurde bereits vorgestellt [1]. Dort wurde ein Gerät vor¬geschlagen, mit dem dieser Wert für verschieden absorbierende Oberflächen für die Dauer einer Exposition akkumuliert wird, und ergänzend eine Abschätzung der Betauungs¬zeiten dieser Referenz-Oberflächen erfolgen könnte. Hier soll es um eine rechnerisch generierte Zusammenstellung dieser photo¬oxidativen 1-Jahres-Alterungswerte für verschiedene Standorte gehen. Ein Temperaturfaktor erfasst dabei den Einfluss der Strahlungserwärmung auf eine weiße, graue bzw. schwarze Referenzoberflächen, spiegelt also die Kopplung von solarer Strahlung und Temperatur wider [1]. Ermittelt wird er aus Stunden¬daten der Globalstrahlung und der Lufttemperatur. Die spektrale Wirkung wird aus Sonnenhöhenständen entsprechend der geografischen Breite mit Hilfe der FastRT-Oberfläche [2] als PiT·h-Wert abgeschätzt [3]. Anhand der errechneten Jahreswerte können die Schweregrade der photo¬oxidativen Beanspruchung an den verschiedenen Standorten unmittelbar verglichen werden. Die gezeigten Simulationsdaten für ein solches „elektronisches Referenzmaterial“ für photooxidative Degradation zeigen die prinzipielle Möglichkeit einer Kartografierung solcher Daten auf. T2 - 53. Jahrestagung der GUS CY - Stutensee-Blankenloch, Germany DA - 26.03.2025 KW - Polymer 3R, UV, Bestrahlung, Bewitterung PY - 2025 SN - 978-3-9826129-2-8 VL - 53 SP - 19 EP - 28 PB - Gesellschaft für Umweltsimulation e.V. CY - 76327 Pfinztal (Berghausen) AN - OPUS4-62902 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Paul, Nathalie A1 - Kister, Alexander A1 - Schnellhardt, Thorben A1 - Fetz, Maximilian A1 - Hecker, Dirk A1 - Wirtz, Tim ED - Meo, Rosa ED - Silvestri, Fabrizio T1 - Reinforcement Learning for Segmented Manufacturing N2 - The manufacturing of large components is, in comparison to small components, cost intensive. This is due to the sheer size of the components and the limited scalability in number of produced items. To take advantage of the effects of small component production we segment the large components into smaller parts and schedule the production of these parts on regular-sized machine tools. We propose to apply and adapt recent developments in reinforcement learning in combination with heuristics to efficiently solve the resulting segmentation and assignment problem. In particular, we solve the assignment problem up to a factor of 8 faster and only a few percentages less accurate than a classic solver from operations research. T2 - European Conference on Machine Learning and Principles and Practice of Knowledge Discovery in Databases 2023 CY - Turin, Italy DA - 18.09.2023 KW - Reinforcement Learning KW - Assignment Problem KW - Large component manufacturing PY - 2025 DO - https://doi.org/10.1007/978-3-031-74640-6_38 VL - 1 IS - 1 SP - 470 EP - 485 PB - Springer Cham AN - OPUS4-63031 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Siefke, Lennart A1 - Linden, Anna T1 - Towards a robust automated surface inspection method for CT-scanned cannulas N2 - For certain cardiovascular diseases, cannulas are implanted into the blood circuit. To match the patients individual anatomy of the heart, there is research for cannulas to be custom-designed and manufactured aided by 3D printing. However, cannulas have to hold very high standards with regard to the smoothness of their surfaces, as rough patches can lead to formation of blood clots. Therefore, this work uses computer vision to detect such patches as part of quality assurance. First, the produced cannula is scanned using a precise CT scanner and transformed into a 3D mesh object. Rough patches in an otherwise smooth but curved surface are detected by using cosine similarity between neighboring faces and a statistical evaluation. In the end, this method is able to raise a warning when curved surfaces are not smooth enough and visualizes the problematic patches. However, there is just limited access to test data currently and the scanner used needs to be upgraded. T2 - 3D in Science & Applications (3D-iSA) 2024 CY - Berlin, Germany DA - 26.11.2024 KW - Algorithm KW - Additive manufacturing KW - Surface evaluation PY - 2025 UR - https://www.gfai.de SN - 978-3-942709-34-7 SP - 66 EP - 70 AN - OPUS4-63057 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schragen, Christian A1 - Lohrer, Christian T1 - A brief journey through the world of standardization of fireworks of the last decade and into the future N2 - This paper aims at giving an overview about this entire standardization process, explaining the main differences of the EN versions from 2015 and 2022, outlining the practical implications for the stakeholders applying these ENs and giving a cautious look into the future requirements for fireworks in Europe. T2 - 19th International Symposium on Fireworks CY - Liling, P.R. China DA - 21.04.2025 KW - Fireworks KW - Standardization PY - 2025 SP - 1 EP - 17 AN - OPUS4-63077 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Pirskawetz, Stephan A1 - Zaripova, Gulshat A1 - Brinkmann, Nienke A1 - Gebraad, Lars A1 - Boehm, Christian A1 - Trattnig, Horst T1 - Simulation der Schallemissionen von Spanndrahtbrüchen N2 - In den 1950er Jahren setzte sich die Spannbetonbauweise für Brücken mit größeren Spannweiten durch. Heute existieren im deutschen Bundesfernstraßennetz ca. 21.000 Spannbetonbrücken. Die mangelnde Erfahrung in der Anfangszeit dieser Bauweise stellt uns heute vor Probleme hinsichtlich einer Kombination aus Korrosion und Ermüdung der Spannglieder. Hauptursachen sind Spannungsrisskorrosion, deutlich gewachsene Verkehrslasten sowie ungenügende Annahmen zu Temperaturlasten. Insbesondere Spanndrahtbrüche infolge Spannungsrisskorrosion können zu einem Strukturversagen ohne Ankündigung führen. Spannstähle mit einer starken Gefährdung für Spannungsrisskorrosion wurden in der Bundesrepublik bis 1965, in der ehemaligen DDR bis Ende der 1980er Jahre verbaut. Um katastrophale Schadensfälle zu verhindern, müssen Bauwerke unter Verdacht auf Spannungsrisskorrosion in Kombination mit unzureichendem Ankündigungsverhalten überwacht werden. Derzeit ist die Schallemissionsanalyse die einzige zuverlässige und ökonomisch vertretbare Überwachungsmethode. Damit kann der sichere Betrieb der Bauwerke über die verbleibende Nutzungsdauer gewährleistet werden. Die DGZfP-Richtlinie SE05 “Detektion von Spanndrahtbrüchen mit Schallemissionsanalyse” beschreibt detailliert Planung, Installation und Betrieb solcher Monitoringsysteme. Im Projekt SimAS “Digitaler Zwilling zur Simulation der Ausbreitung akustischer Wellen in Spannbetonelementen” werden die Grundlagen für eine Optimierung der Monitoringsysteme auf Basis der Schallemissionsanalyse gelegt. Eine akustische Simulation der Struktur und deren Fusion mit Messdaten unterstützt sowohl die vorbereitenden akustischen Analysen der Brücken als auch die Planung der Monitoringsysteme und die Drahtbrucherkennung T2 - SCHALL 25 – Schallemissionsanalyse und Zustandsüberwachung mit geführten Wellen CY - Dresden, Germany DA - 27.03.2025 KW - Acoustic Emission KW - Simulation KW - Schallemission KW - Spannbetonbrücke KW - Spanndrahtbruch KW - Digitaler akustischer Zwilling KW - Spannungsrisskorrosion KW - Schallemissionsanalyse KW - Schallausbreitung PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-628347 DO - https://doi.org/10.58286/30964 VL - 4 SP - 1 EP - 6 PB - Deutsche Gesellschaft für Zerstörungsfreie Prüfung AN - OPUS4-62834 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bulling, Jannis A1 - Gravenkamp, H. A1 - Birk, C. T1 - On the efficient simulation of ultrasonic waves on polygonal meshes N2 - At many stages of technology development in ultrasonic Non-Destructive Testing (NDT) and Structural Health Monitoring (SHM), simulation tools are essential. Many modern approaches to ultrasonic testing, such as Model Assisted Probability of Detection, inverse problems with iterative optimization, or the generation of data for AI training, benefit from highly efficient simulation tools in terms of simulation time. In this talk, we investigate explicit time stepping with the Scaled Boundary Finite Element Method (SBFEM) for approximating the linear elastic wave equation on 2D polygonal meshes, enhanced with a mass lumping technique for faster simulation times. We present the proposed changes to the formulation to successfully use mass lumping. Examples are used to demonstrate that there is no loss of quality due to the approximated mass matrix. Furthermore, mass lumping reduces the simulation time and makes the simulation more efficient. In addition, the proposed simulation method has the advantages of SBFEM meshing techniques. These advantages include fast meshing using an image-based quadtree algorithm or polygonal meshing by transforming triangular meshes based on a CAD model. The latter meshing method can include special crack tip elements that efficiently handle the crack tip singularity. T2 - DAS | DAGA 2025 CY - Copenhagen, Denmark DA - 17.03.2025 KW - Non-Destructive Testing (NDT) KW - Scaled Boundary Finite Element Method (SBFEM) KW - Structural Health Monitoring (SHM) KW - Numerical simulation PY - 2025 UR - https://pub.dega-akustik.de/DAS-DAGA_2025/imprint.html SN - 978-3-939296-23-2 SP - 1592 EP - 1595 AN - OPUS4-63017 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bintz, Thilo A1 - Kruschwitz, Sabine T1 - Non-destructive Testing for the Determination of Durability-Relevant Material Properties of Clinker-Reduced Building Materials N2 - In the quest to combat climate change, the construction industry, heavily reliant on cement-based materials, faces scrutiny due to significant CO2 emissions, mainly from clinker production. To address this, there’s a need to strategically reduce clinker content in cement. However, these new formulations must meet the same requirements as the original ones, so their durability must be investigated. In this study, we determined material parameters that enable an assessment of moisture and ion transport. These methods offer advantages over conventional approaches, including non-destructiveness, reduced measurement time, simplified setup, enhanced resolution, and improvement of detection limits. Our investigation utilizes NDT techniques, using 1H NMR relaxometry for moisture transport and LIBS for ion transport in various clinker-reduced materials. The NMR tomograph provides spatial insights into internal moisture transport, correlated with weight change assessments for the capillary transport coefficient. Additionally, based on NMR relaxometry data the chloride diffusion coefficient is estimated. Chloride migration tests are performed, and results are evaluated using LIBS and indicator tests for the chloride migration coefficient. Our findings highlight NMR relaxometry and LIBS advantages over conventional methods, showcasing superior spatial resolution, non-destructiveness, and, in some cases, expedited results with independence from the formulation of the cement matrix. Thus, these new methods can be used to test the durability of new, more heterogeneous cementbased building. T2 - Rilem Spring Convention 2024 CY - Milano, Italy DA - 10.04.2024 KW - NMR relaxometry KW - LIBS KW - Clinker reduced cement KW - Durability parameters PY - 2025 SN - 978-3-031-70281-5 DO - https://doi.org/10.1007/978-3-031-70281-5_48 VL - 56 SP - 426 EP - 434 AN - OPUS4-61824 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Gaal, Mate A1 - Ahmadzadeh, Majid A1 - Weise, Matthias T1 - Focussed sound field of thermoacoustic transmitters N2 - The thermoacoustic effect offers a method for selectively exciting broadband and focused ultrasonic waves, which can be utilized in air-coupled ultrasonic testing of lightweight components that might otherwise sustain damage from liquid couplants. Thermoacoustic transmitters are composed of an electrically conductive layer deposited on an insulating substrate. When electrical pulses are applied, the conductive layer heats, briefly warming the adjacent air and inducing thermal expansion, which generates an acoustic wave. In testing applications, the thermoacoustic transmitter is positioned at the focal distance to the structure under examination, where the resolution of the resulting ultrasonic image is influenced by the focus diameter. To optimize imaging resolution, understanding the focusing characteristics of thermoacoustic transmitters is essential. In this study, thermoacoustic transmitters with an indium tin oxide (ITO) layer on a quartz glass substrate were developed. Geometrical parameters, including substrate curvature and conductive layer thickness, along with electrical excitation parameters, were systematically varied to investigate their impact on the sound field up to approximately 1 MHz. The results indicate that, among the parameters studied, substrate curvature exerts the most significant influence on the sound field. T2 - DAS-DAGA Tagung CY - Kopenhagen, Danmark DA - 17.03.2025 KW - Air-coupled ultrasound KW - Thermoacoustic transmitter KW - Focussed transducer PY - 2025 SP - 1 EP - 4 AN - OPUS4-63092 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Zhu, J. A1 - Madia, Mauro A1 - Schurig, M. A1 - Kruse, Julius A1 - Conrad, F. A1 - Schlums, H. A1 - Kontermann, C. A1 - Zerbst, Uwe T1 - Anwendung von repräsentativen Proben zur Bewertung der Strukturintegrität von sicherheitsrelevanten Komponenten N2 - Sicherheitsrelevante Bauteile, bei denen ein Versagen im Betrieb katastrophale Folgen haben könnte, sind in der Regel für eine sehr geringe Ausfallwahrscheinlichkeit ausgelegt und unterliegen strengen Qualifizierungsverfahren gemäß den von den Aufsichtsbehörden festgelegten Richtlinien. Die Hersteller sind oft gezwungen, Tests an realen oder skalierten Komponenten durchzuführen, um die Strukturintegrität unter definierten Belastungsbedingungen sicherzustellen, die in der Regel strenger sind als die im Betrieb zu erwartenden. Dies ist in der Regel mit einem enormen experimentellen und finanziellen Aufwand verbunden. Daher versuchen die Unternehmen, neue Strategien wie digitale Zwillinge zu entwickeln, mit denen die Kosten massiv gesenkt werden können, ohne die Sicherheit zu beeinträchtigen. In dieser Arbeit wird ein neues quasistatisches Prüf- und Bewertungskonzept vorgestellt, dessen Hauptidee darin besteht, die experimentelle Prüfung von Bauteilen durch die Prüfung von für das Bauteil repräsentativen Proben zu ersetzen oder zumindest zu reduzieren. Der größte Vorteil des vorgeschlagenen Konzepts besteht darin, dass die Versuche auf Laborprüfmaschinen durchgeführt werden können. Die Wirksamkeit der Methodik wird anhand der Bewertung der Strukturintegrität einer Turbinenscheibe aus einer Ni-Basis-Superlegierung für Flugzeugtriebwerke bei Überdrehzahl demonstriert. T2 - 57. Tagung des DVM-Arbeitskreises Bruchmechanik und Bauteilsicherheit CY - Köln, Germany DA - 18.02.2025 KW - Strukturintegrität KW - Bruchmechanik KW - Turbinenscheibe KW - Repräsentative Proben PY - 2025 DO - https://doi.org/10.48447/BR-2025-536 SP - 231 EP - 240 PB - DVM CY - Berlin AN - OPUS4-62602 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kanna, Naveen A1 - Bär, Jürgen A1 - Duarte, Larissa A1 - Madia, Mauro ED - Ricoeur, Andreas T1 - Ermittlung von Kitagawa-Takahashi-Diagrammen mittels Gleichstrompotentialsondenmessungen N2 - Das Kitagawa-Takahashi Diagramm ist ein wichtiges Werkzeug zur Beschreibung der ausgeprägten Langzeitfestigkeit fehlerbehafteter Bauteile. Insbesondere im technisch relevanten Übergangsbereich unterscheiden sich jedoch die verwendeten Modelle. Daher ist für eine sichere Aussage eine experimentelle Absicherung in diesem Bereich zwingend notwendig. In dieser Arbeit wird eine Methode vorgestellt, die eine einfache und schnelle Absicherung des Verlaufs im Übergangsbereich erlaubt. Hierzu werden in Flachproben mittels eines Gravierlasers scharfe Kerben mit einer definierten Breite und Tiefe eingebracht. Die so präparierten Proben werden mit blockweise steigender Last bis zum Bruch ermüdet. Die Erkennung von Anrissen erfolgt mittels einer Gleichstrom-Potentialsonde mit der auch die Länge des Lastblocks gesteuert wird. T2 - 57. Tagung des DVM-Arbeitskreises Bruchmechanik und Bauteilsicherheit CY - Cologne, Germany DA - 18.02.2025 KW - Ausgeprägte Langzeitfestigkeit KW - Materialdefekte KW - KT-Diagramm KW - Gleichstrom-Potentialsonde PY - 2025 DO - https://doi.org/10.48447/BR-2025-513 VL - 257 SP - 105 EP - 112 PB - Deutscher Verband für Materialforschung und -prüfung e.V. CY - Berlin, Deutschland AN - OPUS4-62604 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Wachtendorf, Volker A1 - Wägner, Yannick A1 - Geburtig, Anja T1 - Gedanken, Tipps & Tricks zu künstlichen Bewitterungsprüfungen N2 - Die Fragestellung kann nur exemplarisch dargestellt werden, aber ist hoffentlich auch für langjährige Praktiker in den ausgewählten Punkten interessant. Es sollen für folgende Bereiche Beispiele gegeben werden: Probenvorbereitung, Testvorbereitung, Testdurchführung und Auswertung. T2 - 53. Jahrestagung der GUS 2025 CY - Stutensee-Blankenloch bei Karlsruhe, Germany DA - 26.03.2025 KW - Wechseltemperaturen KW - Künstliche Bewitterung KW - Prüfung KW - UV KW - Feuchte KW - Beregnung PY - 2025 SN - 978-3-9826129-2-8 VL - 53 SP - 253 EP - 257 PB - Gesellschaft für Umweltsimulation e.V. CY - 76327 Pfinztal (Berghausen) AN - OPUS4-62861 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Eichner, Lukas A1 - Schneider, Ronald A1 - Baeßler, Matthias T1 - Probabilistische Systemidentifikation einer Versuchsstruktur für Substrukturen von Offshore-Windenergieanlagen mit statischen und dynamischen Messdaten N2 - In diesem Beitrag wird ein probabilistischer Ansatz zur Systemidentifikation für Tragstrukturen von Offshore-Windkraftanlagen vorgestellt. Der Schwerpunkt der Forschung liegt auf der Integration von globalen Systemantworten in Form von Eigenfrequenzen und -formen sowie Verschiebungen und Dehnungen als lokale Messdaten. Die unterschiedlichen Daten werden kombiniert für die Aktualisierung der Parameter eines Finite-Elemente-Modells genutzt. Zu diesem Zweck wird ein probabilistischer Ansatz nach Bayes verfolgt, um Vorwissen sowie Unsicherheiten einzubeziehen. Die Methodik wird bei einer Versuchsstruktur angewandt, die eine Jacket-Substruktur von Offshore-Windenergieanlagen nachbildet. Eine Systemidentifikation mit Hilfe von Überwachungsdaten ist wertvoll für Jacket-Substrukturen, da eine Zustandsanalyse für die Gewährleistung der strukturellen Integrität unerlässlich ist, aber hinsichtlich der schwierigen Offshore-Bedingungen möglichst effizient sein muss. In diesem Zusammenhang schafft diese Arbeit die Grundlage für eine Schadenserkennung, eine verbesserte Vorhersage der Ermüdungslebensdauer und optimierte Instandhaltungsstrategien. Während das Modell hinsichtlich der statischen Messdaten erfolgreich aktualisiert werden kann, sind Schwierigkeiten bei der Identifizierung der dynamischen Systemeigenschaften erkennbar. T2 - 8. VDI-Fachtagung Baudynamik 2025 CY - Würzburg, Germany DA - 02.04.2025 KW - Systemidentifikation KW - Versuchsstruktur KW - Jacket KW - Offshore-Windenergie PY - 2025 VL - 8 SP - 175 EP - 188 AN - OPUS4-62879 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rückschloss, Jana A1 - Tochtrop, Christoph A1 - von Geibler, Justus A1 - Schlegel, Moritz-Caspar T1 - “Oh no, it’s broken!” – How product functionality limits lifespan N2 - Today a large variety of products with various features and designs are available for consumers. In addition to the main functions of a product, there are more and more additional functions, especially for electrical and electronic appliances. This means that looking for the right product may require extensive research by consumers and does not always lead to a sense of making an informed purchase decision. The wide variety of designs and functions can overwhelm consumers. This creates uncertainty and might lead to overrate products functionality and thus significantly shorten the service lifetime of appliances. Furthermore, the environmental impact of such functions is usually unclear, and can vary depending on the actual usage scenario. In this study, a survey was carried out in order to better understand consumers perceptions and experiences related to additional functions of products, with specific focus on domestic hobs, household refrigerating appliances and televisions. The results confirm the large number of additional functions and their overwhelming effect for consumers. Consumers purchase devices with more features than desired, or replaced them prematurely because an extra feature fails while the main function is still available. The findings of the study can be used to better inform consumers and support them to make environmentally sustainable purchasing decisions. T2 - 6th Product Lifetimes and the Environment Conference (PLATE2025) CY - Aalborg, Denmark DA - 02.07.2025 KW - Circular economy KW - Functionality KW - Durability KW - Purchase decision KW - Ecodesign PY - 2025 UR - https://journals.aau.dk/index.php/plate2025 SN - 97887-7642-060-4 DO - https://doi.org/10.54337/plate2025 SN - 2794-9540 SP - 666 EP - 674 AN - OPUS4-63823 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Maack, Jürgen A1 - Eidenmüller, Moritz A1 - Auersch, Lutz T1 - Prognose von Erschütterungs- und Sekundärschall- Immissionen an Bahnlinien unter Verwendung von FEM Gebäudemodellen N2 - Die Errichtung von Wohngebäuden an Bahnstrecken erfordert Betrachtungen zur Begrenzung der Erschütterungs- und Sekundärschallimmissionen. Hierzu werden spektrale Prognoseverfahren ausgehend von Freifeldmessungen eingesetzt. Im rechnerischen Modell werden die Teilaspekte der Körperschallübertragung mit Hilfe von spektralen Übertragungsfunktionen beschrieben. Kenntnis über die Zusammenhänge dieser spektralen Übertragungsfunktionen erhält man im Wechselspiel von: - Messergebnissen von Körperschall- und Luftschallmessungen für einzelne Übertragungssysteme - Modellberechnungen mit der Finite-Elemente-Methode, Parameterstudien, Abgleich mit Messergebnissen - Modellberechnung mit der Finite-Elemente-Methode zur Wechselwirkung des schwimmenden Estrichs mit dem Gebäude T2 - VDI-Tagung Baudynamik CY - Würzburg, Germany DA - 02.04.2025 KW - Bahnerschütterungen KW - Gebäudemodelle KW - Schwimmender Estrich KW - Sekundärschall PY - 2025 SN - 978-3-18-092447-2 SN - 0083-5560 VL - 2447 SP - 301 EP - 314 PB - VDI-Verlag CY - Düsseldorf AN - OPUS4-62887 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz T1 - Erschütterungsprognose mit KI? Schnelle Ersatzmodelle und physikbasiertes maschinelles Lernen in der Bauwerk-Boden-Dynamik N2 - Erschütterungsprognosen können mit sehr detaillierten Modellen durchgeführt werden. Dies ist sowohl bei der Erstellung des Modells (zum Beispiel für ein Finite-Element-Modell für Boden und Bauwerk), als auch bei der Berechnung zeitaufwändig, von einigen Minuten für die Wellenausbreitung in geschichteten Böden mit Wellenzahlintegralen bis zu mehreren Stunden für Randelementlösungen für die korrekte Bauwerk-Boden-Wechselwirkung. Hier sind einfache und schnelle Ersatzmodelle von Vorteil, die die Ergebnisse der detaillierten Berechnungen gut wiedergeben. Diese Ersatzmodelle können vollständig auf physikalischen Überlegungen beruhen (white-box Modelle) oder mit Hilfe von maschinellem Lernen aus einer Vielzahl von detaillierten Rechenergebnissen erzeugt werden (black-box Modelle). Erfahrungen mit black-box Modellen zeigen, dass es sinnvoll ist das maschinelle Lernen mit physikalischen Informationen anzureichern (grey-box Modelle). Es werden Anwendungsmöglichkeiten für physikbasiertes maschinelles Lernen im Bereich von Bahnerschütterungen aufgezeigt, die Erschütterungsemission durch die Fahrzeug-Fahrweg-Wechselwirkung, die Wellenausbreitung im Boden, die Erschütterungsimmission in Gebäude, Gleisschäden und das Monitoring von Eisenbahnbrücken. T2 - VDI-Tagung Baudynamik CY - Würzburg, Germany DA - 02.04.2025 KW - Bahnerschütterungen KW - Emissionsmodell KW - Immissionsmodell KW - Transmissionsmodell KW - Tunnelausbreitung KW - Gleisüberwachung PY - 2025 SN - 978-3-18-092447-2 SN - 0083-5560 VL - 2447 SP - 53 EP - 64 PB - VDI-Verlag CY - Düsseldorf AN - OPUS4-62886 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz ED - Papadrakakis, Manolis T1 - Frequency-wavenumber method for the wave propagation through the soil and the soil-structure interaction of railway tracks and building foundations near railway lines N2 - In soil-structure interaction, the soil and the (flexible) structures are modelled as elastic continua. The partial differential equations of elasticity can be transformed to algebraic equations in frequency-wavenumber domain where they can be solved by matrix methods. The results for the soil and a structure can be coupled in frequency-wavenumber domain, and the solution in space domain is obtained by an infinite wavenumber integral (the back-transformation). This method has several applications for the prediction of the emission, transmission and immission of railway-induced vibrations. The wave propagation in homogeneous or layered soils is calculated for surface and tunnel lines by a single wavenumber integration (transmission). The response of ballast or slab tracks (for the emission problem) and the foundation stiffness (for the immission problem) need an additional integration across the track or foundation width. In wavenumber domain, tracks and foundations of infinite length are analysed. Finite structures can be calculated by finite element models where the soil is calculated by the boundary element method. The Green’s functions for the boundary element method are calculated by a wavenumber integration as for the transmission problem. Some example results for all these tasks will be shown. The immission into buildings will be analysed in detail, and the effect of stiff slab foundations and (basement) walls on the incoming wavefield is quantified in a parameter study. The transfer function (the amplitude ratio) structure to free field usually starts with 1 at 0 Hz and decreases continuously with frequency. The reduction is due to the structural stiffness against wave deformation which turns to be higher than the stiffness of the soil, for example above the structure-soil coincidence frequency of the slab foundation. The reduction is better for a high structural stiffness and for a low soil stiffness. Walls are stiffer than plates for the relevant frequency range, but even walls and especially low basement walls are not infinitely rigid and can follow the wave deformation to a certain extent. These basic rules from frequency-wavenumber analysis can well be used for real building projects near railway lines where stiff foundations can be an alternative reduction method to the commonly used base isolation by elastic elements. T2 - COMPDYN 2025 CY - Rhodos, Greece DA - 15.06.2025 KW - Frequency-wavenumber method KW - Wave propagation KW - Soil-structure interaction KW - Building foundations KW - Mitigation measures PY - 2025 SP - 1 EP - 15 PB - NTUA CY - Athen AN - OPUS4-63470 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Fünning, Tabea A1 - Peczek, Anna A1 - Kroh, Aleksandra A1 - Mai, Christian A1 - Paul, Martin A1 - Thomsen, Florian A1 - Tannenberg, Robert A1 - Schumann, Christoph A1 - Weller, Michael G. A1 - Mai, Andreas A1 - Steglich, Patrick C. ED - Lieberman, Robert A. ED - Baldini, Francesco ED - Homola, Jiri T1 - Optimization of local backside released micro-ring resonators for sensing applications using silicon photonic integrated circuits in a SOI technology N2 - Photonic micro-ring resonators (MRR) are widely studied for their high sensitivity across applications like environmental monitoring, healthcare, and chemical analysis. Their evanescent field sensing requires partially unembedded waveguides compatible with CMOS processing. Our approach uses local backside etching with an additional buried oxide (BOX) etch to release waveguides while preserving the back-end of line (BEOL) structure, enabling spatial separation of the sensing area and electronics. The BOX etch critically affects sensor performance, as waveguide surface roughness can alter MRR properties and coupling. We analyzed MRR design variations, comparing wet and dry etching techniques for their effects on optical performance across rib and strip waveguides in quasi-TE and quasi-TM modes. Wafer-level measurements show that backside-released MRR achieve high extinction ratios with slightly reduced quality factors, advancing high-sensitivity photonic sensors. T2 - SPIE Optics + Optoelectronics 2025 CY - Prague, Czech Republic DA - 23.05.2025 KW - Photonic sensors KW - Micro-ring resonator (MRR) KW - Silicon on insulator (SOI) KW - CMOS KW - Local backside etching PY - 2025 SN - 978-1-5106-8851-3 DO - https://doi.org/10.1117/12.3056481 VL - 13527 SP - 1 EP - 8 PB - SPIE CY - Bellingham, WA , USA AN - OPUS4-63585 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Tannenberg, Robert A1 - Paul, Martin A1 - Fünning, Tabea A1 - Schuhmann, Christoph A1 - Weller, Michael G. A1 - Steglich, Patrick T1 - Multichannel real-time detection of biomarkers with highly miniaturized photonic microchips N2 - The development of novel photonic integrated microchips (PIC) is a promising approach to allow for the convenient detection of key biomarkers in complex matrices through multichannel real-time analysis in a highly compact package. This study reports the successful development and application of a backside released CMOS chip designed for the multichannel real-time detection of biomarkers. Operating at the C-band at approx. 1550 nm, the microchip features three dedicated detection sensors in addition to a reference sensor, enabling simultaneous analysis of multiple biomarkers. The compact and highly miniaturized design of this microchip, with a footprint of just 1 mm², positions it as promising candidate for point-of-care diagnostics and personalized medicine applications. This technology opens a path to transform biomarker detection across various medical fields, offering rapid, reliable, and cost-effective diagnostic solutions. In conclusion, the presented multichannel photonic microchips signify a substantial leap forward in real-time biomarker detection, providing a highly capable platform for future research and clinical applications. T2 - SPIE Optics + Optoelectronics 2025 CY - Prague, Czech Republic DA - 07.04.2025 KW - Photonic integrated circuit KW - Ring resonator KW - Real-time detection KW - Multiplexing KW - Semiconductor KW - CMOS KW - C-reactive protein KW - CRP KW - Biomarker PY - 2025 SN - 978-1-5106-8850-6 DO - https://doi.org/10.1117/12.3056453 VL - 13527 SP - 1 EP - 6 PB - SPIE CY - Prague, Czech Republic AN - OPUS4-63478 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rolle, Annette A1 - Wille, Frank A1 - Komann, Steffen A1 - Neumann, Martin T1 - Qualification Procedure for Seal Designs for Spent Fuel Transport and Storage Cask Containments N2 - The seal is a key component of the containment and closure system of transport and storage casks for radioactive material. It is a major contributor to ensuring compliance with the acceptable limits for activity release according to IAEA regulations. The requirements for a safe seal performance are high, accordingly. Every new seal design intended for use in the containment of a transport cask for radioactive material passes a qualification process in Germany. The qualification process is supervised by BAM as German competent authority for mechanical, thermal and containment assessment of packages requiring design approval. The closure system including the seal shall be able to withstand the corrosive, mechanical and thermal loads associated with routine, normal and accident conditions of transport according to the IAEA regulations without losing the required sealing function. Metal seals of the Helicoflex® type are often used to ensure required package leak tightness for both storage and transport, including transport after long term interim storage. The poster will provide an overview of requirements during a seal qualification process on the example of a Helicoflex® type metal seal. T2 - 21st International Symposium on the Packaging and Transportation of Radioactive Materials, PATRAM 2025 CY - San Antonio, Texas , US DA - 27.07.2025 KW - Spent fuel transport KW - Seals KW - Radioactive KW - Containment PY - 2025 SP - 1 EP - 5 AN - OPUS4-63911 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rhode, Michael A1 - Czeskleba, Denis A1 - Irfan, Muhammad Dary A1 - Wandtke, Karsten A1 - Kaiser, Sebastian A1 - Kannengießer, Thomas T1 - Wasserstoffdiffusion in hochfesten UP-Schweißverbindungen – einfacher als gedacht N2 - Hochfeste Baustähle werden im modernen Stahlbau aus wirtschaftlichen und konstruktiven Gründen zunehmend eingesetzt, z. B. im Gebäude-, Anlagen- oder Mobilkranbau. Durch den Einsatz von Stählen mit höheren 690 MPa) können durch die Reduzierung der Wanddicke erhebliche Gewichtsreduzierungen und geringere Verarbeitungskosten erreicht werden, insbesondere bei der Verwendung des Unterpulverschweißen (UP) durch seine hohe Abschmelzleistung. Aufgrund ihrer speziellen Mikrostruktur haben hochfeste Stähle eine begrenzte Duktilität und sind anfälliger für wasserstoffunterstützte Kaltrisse (HACC). Darüber hinaus führen große mittels UP geschweißter Blechdicken zu hohen Schweißeigenspannungen und langen Diffusionswegen für z.B. durch den Schweißprozess eingebrachten Wasserstoff. Abgesicherte Diffusionskoeffizienten für UP-Schweißungen dieser Festigkeitsklasse sind als Grundlage für die Abschätzung des Zeitintervalls einer möglichen verzögerten Kaltrissbildung oder für Nachwärmung zur Wasserstoffreduktion nur sehr begrenzt verfügbar. Aus diesem Grund wurden experimentelle Versuche zur mikrostruktur-spezifischen Diffusion in S690-Schweißungen durchgeführt. Dazu wurde ein thermomechanisch (TM) gewalzter bzw. vergüteter (QL) Zustand dieses Werkstoffs betrachtet, sowie das jeweilige charakteristische Schweißgut und WEZ. Dazu wurden den Schweißmikrostrukturen lokal Proben entnommen und über Permeations- bzw. Warmauslagerungsversuche die gefügespezifische Diffusion von Raumtemperatur bis 400°C charakterisiert. Im Gegensatz zu bekannten Effekten des Wärmebehandlungszustandes der Grundwerkstoffe auf die Diffusion in MSGSchweißverbindungen, zeigten die Wasserstoffdiffusionskoeffizienten über alle untersuchten Gefügezustände keine signifikanten Unterschiede, insbesondere nicht für die lokale WEZ diverser, untersuchter Streckenergiebereiche. Aus praktischer Anwendersicht können daher dickwandige UP-Verbindungen hinsichtlich einer verzögerten Wasserstoffdiffusion nur anhand der einfach ermittelbaren Diffusionskoeffizienten für den Grundwerkstoffkoeffizient beurteilt werden. Zudem zeigte sich, dass der unterschiedliche Walz- und Wärmebehandlungszustand (TM vs. QL) in UP-Schweißnähten eine untergeordnete Rolle für die Wasserstoffdiffusion und damit für die mögliche Zeitverzögerung der Kaltrissbildung hat. Ergänzende numerische Simulationen der Wasserstoffverteilung bestätigten das Verhalten. T2 - DVS Congress 2025 CY - Essen, Germany DA - 16.09.2025 KW - Unterpulverschweißen KW - Wasserstoffdiffusion KW - Wasserstoffunterstützte Kaltrissbildung KW - Wasserstoffrisse PY - 2025 SN - 978-3-96144-299-7 DO - https://doi.org/10.53192/DVSC20250330 VL - 401 SP - 330 EP - 340 PB - DVS Media GmbH CY - Düsseldorf AN - OPUS4-64132 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Gleim, Tobias A1 - Monavari, Mehran A1 - Bertovic, Marija A1 - Wille, Frank T1 - AI-driven Documentation Analysis for Safety Assessment of Packages with Hazardous Goods N2 - Transport packages for radioactive material require, dependent on type und quantity of the radioactive material, a regulatory approval. Safety assessments shall be conducted in compliance with the IAEA regulations and documented in a comprehensive package design safety report to obtain approval from authority. This comprehensive safety report evaluates a broad range of requirements from the regulations, including physical specifications, control measures, and testing assessments. Additionally, it encompasses supporting documents such as specifications, plans in a variety of complex documents. Safety and manufacturing reports contain multiple interconnected sub-reports covering various topics. Changes, such as component modifications, material property updates, standards, or regulatory revisions, often impact multiple sections of the safety analysis reports, making even minor adjustments complex and time-consuming. Each transport package has unique constraints, making every safety report distinct, despite following the same regulatory framework. This project aims to enhance data analysis and processing through AI-based approaches [4]. Automated methods for analysing and interlinking documentation will improve efficiency, accuracy, and consistency while reducing human error in safety assessments. A key challenge is that pre-trained Large Language Models (LLMs) lack domain-specific data on packaging safety, potentially leading to inaccurate results. To mitigate this, the project applies Retrieval-Augmented Generation (RAG) in conjunction with LLMs. This approach integrates the strengths of pre-trained models with expert knowledge from databases and document repositories, ensuring accurate, well-founded, and transparent assessments. Beyond technical challenges, human factors must be considered early. New technologies often trigger resistance, if not introduced properly. Furthermore, long-term AI-reliance may lead to loss of expertise needed to solve complex problems. User-centred approach ensures effective implementation and lasting viability. This study evaluates the feasibility of using LLMs [2] and RAG [1, 3] for regulatory compliance in radioactive material transport. By analysing current documentation workflows, we assess how AI-driven tools can interpret complex safety reports and identify critical dependencies. Furthermore, we highlight the necessity of robust data governance, confidentiality measures, and AI reliability in this highly regulated domain. T2 - KONTEC 2025 CY - Dresden, Germany DA - 17.09.2025 KW - AI-driven KW - QI-Digital KW - Retrieval-Augmented Generation KW - Large Language Model PY - 2025 SP - 1 EP - 9 PB - Kontec Gesellschaft für technische Kommunikation GmbH CY - Dresden AN - OPUS4-64154 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Lecompagnon, Julien A1 - Rooch, Ludwig A1 - Hassenstein, Christian A1 - Ziegler, Mathias ED - Sakagami, T. ED - Inoue, H. T1 - Total Focusing in the Virtual Wave Domain: 3D Defect Reconstruction Using Spatially Structured Laser Heating N2 - Classical active thermographic testing of industrial goods has mostly been limited to generating 2D defect maps. While for surface or near-surface defect detection, this is a desired result, for deeply buried defects, a 3D reconstruction of the defect geometry is coveted. This general trend can also be well observed in widely used NDT methods (radiography, ultrasonic testing), where the progression from 2D to 3D reconstruction methods has already made profound progress (CT, UT phased array transducers). Achieving a fully 3D defect reconstruction in active thermographic testing suffers from the diffusive nature of thermal processes. One possible solution to deal with thermal diffusion is the application of the virtual-wave concept, which, by solving an inverse problem, allows the diffusiveness to be extracted from the thermographic data in the post-processing stage. What is left follows propagating-wave physics, enabling the usage of well-known algorithms from ultrasonic testing. In this work, we present our progress in the 3D reconstruction of deeply buried defects using spatially structured laser heating in conjunction with applying the well-known total focusing method (TFM) in the virtual-wave domain. T2 - 18th International Workshop on Advanced Infrared Technology and Applications (AITA 2025) CY - Kobe, Japan DA - 15.09.2025 KW - Non-destructive testing KW - Virtual wave concept KW - Laser thermography KW - Thermal thomography PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-641463 DO - https://doi.org/10.3390/proceedings2025129054 VL - 129 IS - 1 SP - 1 EP - 5 PB - MDPI CY - Basel AN - OPUS4-64146 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schepers, Winfried T1 - Die Courant-Friedrichs-Lewy-Bedingung als Genauigkeits- und Stabilitätsbedingung bei FEM-Berechnungen zur Wellenausbreitung N2 - Bei numerischen Berechnungen zur Wellenausbreitung im Zeitbereich mit der FE-Methode wird sehr häufig die Courant-Friedrichs-Lewy-Bedingung als zwingend einzuhaltende Bedingung für das Zeitschrittintegrationsverfahren genannt. Darin wird gefordert, dass eine sich ausbreitende Welle innerhalb eines Zeitschritts nicht mehr als die Distanz zum nächstgelegenen Knotenpunkt zurücklegen dürfe. Dies lässt erwarten, dass es sich um eine physikalisch begründbare Bedingung handelt. Es ist jedoch in der Literatur zu beobachten, dass nicht weiter ausgeführt wird, ob es sich um eine Genauigkeits- oder um eine Stabilitätsbedingung handelt, und ob sie für alle Zeitschrittverfahren einzuhalten ist oder nur für einige spezielle. Auch werden entsprechende Aussagen ohne weiteren Quellennachweis gemacht. Dieser Beitrag erläutert zunächst die Fragestellung, der Courant et al. in der Originalveröffentlichung von 1928 nachgegangen sind, und zeigt auf, welche Bedeutung die von ihnen gefundene Beziehung für die dort untersuchte Fragestellung hat. Anschließend wird der Frage nachgegangen, inwieweit die dort gewonnenen Erkenntnisse auf FEM-Berechnungen übertragen werden können. Die Betrachtung der Stabilitätsbedingungen verschiedener Zeitschrittintegrationsverfahren im Kontext von FEM-Berechnungen in der Strukturdynamik zeigt anschließend, dass es sich bei der CFL-Bedingung nicht um eine physikalisch begründbare Beziehung, sondern um eine rein numerische Bedingung ohne physikalischen Hintergrund handelt. T2 - 19. D-A-CH Tagung Erdbebeningenieurwesen und Baudynamik CY - Vienna, Germany DA - 18.09.2025 KW - Numerische Methoden KW - Zeitschrittintegration KW - Verkehrserschütterungen PY - 2025 SN - 978-3-200-10710-6 DO - https://doi.org/10.34726/10599 SP - 259 EP - 264 PB - Österreichische Gesellschaft für Erdbebeningenieurwesen und Baudynamik (OGE) CY - Wien AN - OPUS4-64191 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schepers, Winfried T1 - Kritische Betrachtung der Impedanzfunktionen harmonisch angeregter Fundamente N2 - In den aktuellen Entwürfen des Eurocode 8 Teil 5 (FprEN 1998-5:2024) und auch des Euro-codes 7 Teil 3 (E DIN EN 1997-3:2022-10) werden Formeln für die Steifigkeiten eines Hal-braums mit einem darin eingebetteten starren masselosen Rechteckfundament gegenüber einer harmonischen Anregung angegeben. Die Formeln sind im Wesentlichen eine Kombination der Ergebnisse der Veröffentlichungen von Gazetas (1991) und Pais et al. (1988) über Forschungs-arbeiten, die in den 1980er Jahren durchgeführt wurden. Sie basieren auf numerischen Berech-nungen, deren Ergebnisse durch Ausgleichskurven approximiert wurden. Eine genauere Analyse der den Formeln zugrunde liegenden Veröffentlichungen zeigt einige Inkonsistenzen zwischen Eurocodes und den ursprünglichen Veröffentlichungen, deren Ursache nicht ohne weiteres er-kennbar ist. Darüber hinaus werden in den Eurocodes nur frequenzunabhängige Steifigkeiten angegeben. Das führt zu der Frage, wie verlässlich die Formeln sind. An zwei Beispielen wird nachfolgend die Notwendigkeit einer kritischen Verwendung der Impedanzfunktionen gezeigt. T2 - 19. D-A-CH Tagung Erdbebeningenieurwesen und Baudynamik CY - Vienna, Austria DA - 18.09.2025 KW - Impedanzen KW - Wellenausbreitung KW - Erschütterungen PY - 2025 SN - 978-3-200-10710-6 DO - https://doi.org/10.34726/10599 SP - 245 EP - 246 PB - Österreichische Gesellschaft für Erdbebeningenieurwesen und Baudynamik (OGE) CY - Wien AN - OPUS4-64187 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Brunner, Nanine A1 - Melzer, Michael T1 - Digital Certificates: Enabling Automation in Quality Assurance and Metrological Traceability N2 - Automation in the metrological traceability of measurements bears high potential for a more effective quality management with less human interaction and reduced risks from manual data processing. For this purpose all metrological and administrative information in quality certificates must be provided in a fully machine-readable and machine-interpretable form. Following the well-established approach of dig-ital calibration certificates (DCCs) also other digital quality certificates are currently under development. T2 - SMSI 2025 Conference – Sensor and Measurement Science International CY - Nuremberg, Germany DA - 06.05.2025 KW - Digital metrology KW - Calibration KW - Quality assurance KW - Reference materials KW - Automation PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-641930 SN - 978-3-910600-06-5 DO - https://doi.org/10.5162/SMSI2025/C6.4 SP - 171 EP - 172 PB - AMA Service GmbH CY - Wunstorf AN - OPUS4-64193 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ebell, Gino A1 - Scheerer, S. A1 - Fiedler, M. A1 - Schacht, G. A1 - Ritter, R. A1 - Marzahn, G. A1 - Marx, S. T1 - Die wechselvolle Geschichte der Carolabrücke in Dresden N2 - Am 11. September 2024 fand in Dresden ein Ereignis statt, welches man in Deutschland nicht erwartet hatte: der Teileinsturz einer Spannbetonbrücke unter Betrieb ohne Vorankündigung. Die Dresdner Carolabrücke war eine Ikone der Ingenieurbaukunst ihrer Zeit. Sie war ein sehr ästhetisches und schlankes Bauwerk. Ihre Konstruktion und Bau wären auch heute noch eine Herausforderung. Die vorhandenen Unterlagen zeugen von einer hohen Entwurfsqualität und einer sehr sorgsamen Bauausführung. Im Beitrag werden die Entstehungsgeschichte, die Konstruktion selbst und der Bau der Brücke vorgestellt. Es wird der Versuch der Rekonstruktion des Einsturzvorgangs unternommen und die Suche nach der Einsturzursache beschrieben. Am Schluss des Beitrags wird auf das aktuelle Überwachungskonzept eingegangen und ein Ausblick auf das mögliche weitere Vorgehen gegeben. T2 - 34. Dresdner Brückenbausymposium CY - Dresden, Germany DA - 19.03.2025 KW - Spanungsrisskorrosion KW - Wasserstoff KW - Spannstahl KW - Brücke PY - 2025 SP - 15 EP - 33 CY - Dresden AN - OPUS4-63063 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Zinas, Orestis A1 - Papaioannou, Iason A1 - Schneider, Ronald A1 - Cuéllar, Pablo A1 - Baeßler, Matthias T1 - 3D spatial modelling of CPT data for probabilistic preliminary assessment of potential pile tip damage upon collision with boulders N2 - Tip damage of monopiles from boulder collisions during installation has emerged as a critical design issue, primarily due to the combination of the widespread use of large-diameter piles and the complexity of the ground conditions at the available sites. Recently, a framework relating potential pile tip damage to cone tip resistance from Cone Penetration Tests (CPTs) has been proposed in the literature. Gaussian processes are powerful stochastic models that enable probabilistic spatial interpolation of soil data at any location within a site. On this basis, this study utilizes sparse CPT data from a site in the North Sea, to first develop an efficient Gaussian process regression model, which is used to derive a three-dimensional (3D) probabilistic predictive map of the cone tip resistance. Assuming deterministic loading conditions and a factual collision with a boulder of pre-defined properties, the cone tip resistance predictive model is subsequently used for a probabilistic preliminary assessment of potential pile tip damage. Results of the analysis are realistic 3D probability maps of potential damage that aim to support engineering judgment and contribute towards cost-effective site investigation planning and offshore wind farm design. T2 - 5th International Symposium on Frontiers in Offshore Geotechnics (ISFOG 2025) CY - Nantes, France DA - 09.06.2025 KW - CPT data KW - Gaussian process regression KW - Boulder impact KW - Preliminary pile tip damage assessment PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-634417 SN - 978-2-85782-758-0 DO - https://doi.org/10.53243/ISFOG2025-323 SP - 505 EP - 510 PB - International Society for Soil Mechanics and Geotechnical Engineering CY - London AN - OPUS4-63441 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Baeßler, Matthias A1 - Balscheit, Hagen A1 - Geißler, Peter A1 - Schepers, Winfried A1 - Cuèllar, Pablo T1 - Evaluation of pile tip buckling based on large scale tests N2 - Der Beitrag beschreibt eine groß angelegte Versuchskampagne mit Pfahlrammungen, um das Risiko des plastischen Versagens der Pfahlspitze besser zu verstehen und numerische Modelle zu validieren. Ein numerisches Modell mit transientem Bodenkontakt zeigt eine gute Übereinstimmung mit den Testergebnissen. Parametervariationen verdeutlichen, wie empfindlich die Pfahlreaktion auf Imperfektionen und Randbedingungen ist. T2 - 5TH INTERNATIONAL SYMPOSIUM ON FRONTIERS IN OFFSHORE GEOTECHNICS CY - Nantes, France DA - 09.06.2025 KW - Pile Tip Buckling KW - Monopile KW - Offshore Windenergy KW - Driving Refusal KW - Large Scale Test PY - 2025 SN - 978-2-85782-758-0 DO - https://doi.org/10.53243/ISFOG2025-476 SP - 1218 EP - 1223 PB - International Society for Soil Mechanics and Geotechnical Engineering (ISSMGE) CY - Nantes AN - OPUS4-63387 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Reichel, Levin A1 - Kromm, Arne A1 - Michael, Thomas A1 - Schroepfer, Dirk A1 - Kannengiesser, Thomas T1 - Modern welding processes for optimizing repair welding on high-strength offshore steels N2 - The successful energy transition in Germany will require offshore wind turbines with outputs >10 MW in the future, for which high-strength steels with a yield strength of up to 500 MPa and wall thicknesses up to 150 mm are increasingly being used. The repair of weld seams when detecting defects during NDT requires localized gouging and rewelding. This involves high demands on welding manufacturing, especially for highstrength steels. Due to a lack of investigations, there are no repair concepts and information in standards and guidelines, particularly for high-strength thick plate joints made of high-strength offshore steels. However, these are urgently needed to enable processors, especially SMEs, to carry out safe and economical repairs. Therefore, BAM startedthe FOSTA project P1629 (IGF 01IF22746N) to investigate the stress-optimized repair(local gouging and welding) of high-strength thick plate joints made of offshore grades in the yield strength range off 355 to 460 MPa and similar weld metal with controlled high-performance GMAW processes and optimized narrower gouging grooves. The experimental analyses consider the complex interaction of material, process, and designrelated influences on the formation of weld-related stresses and the special microstructure of high-strength fine-grain structural steels. Welding-related material Degradation and crack-critical residual tensile stresses need to be avoided to ensure high component safety and performance. With component-related welding experiments on special testing equipment, adapted process and heat control concepts along with variable groove configurations will be developed and recommendations for guidelines elaborated. This is the prerequisite for fully utilizing the strength potential of high-strength steels and making a valuable contribution to the energy transition in Germany, especially for steelprocessing SMEs. T2 - 6. Symposium Materialtechnik CY - Clausthal-Zellerfeld, Germany DA - 20.02.2025 KW - Narrow groove KW - Optimized repair welding KW - Modern welding processes KW - High-strength steel PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-636520 DO - https://doi.org/10.21268/20250507-5 SP - 3 EP - 15 AN - OPUS4-63652 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Nagelschmidt, Sven T1 - Application study of time-temperature correlation methods on test data of metal seals N2 - Reliable experimental data and prediction models are required to evaluate the behavior of components and materials over long periods of time. One method is based on the time-temperature equivalence principle, according to which a state or material property occurs or can be achieved equivalently at different time-temperature combinations. Higher temperatures generally shorten the duration and vice versa. Based on this approach, the long-term behavior of metal seals, as used in storage containers for spent nuclear fuels and high-level radioactive waste, has been studied at BAM and other institutions around the world for several years. However, such tests are often not planned as a preliminary point regarding the basic conditions of time-temperature related models. Gaps are then sometimes identified during the evaluation, for example because certain temperature values are missing, or the measurement intervals were not selected appropriately. This study evaluates exemplarily the status of the test data of metal seals at the BAM regarding the applicability of existing time-temperature correlation methods and corresponding models. Based on the existing database, the aim is to show which method and model are more likely to be applicable and which additional tests might be necessary to obtain a more suitable database. The tests so far have provided important findings for the planning and adaptation of possible further tests and for suitable model developments. Identified gaps in the data basis led to further development of the methods. In the present work, a time-temperature correlation was determined based on a time-temperature parameter from GRAHAM and WALLES for a selected data range. T2 - Pressure Vessels & Piping Conference PVP2025 CY - Montreal, Canada DA - 20.07.2025 KW - Time-temperature equivalence KW - Metal seals, KW - Time-temperature superposition KW - Time-temperature parameters PY - 2025 VL - 2025 SP - 1 EP - 4 PB - ASME CY - USA AN - OPUS4-63789 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ghaznavi, Ali A1 - Kästle, Emanuel D. A1 - Popiela, Bartosz A1 - Duffner, Eric T1 - Damage monitoring of hydrogen composite pressure vessels using acoustic emission technique and machine learning N2 - A good understanding of the structural stability of hydrogen composite overwrapped pressure vessels (COPV) is important for the cost-effective design and safe operation of hydrogen storage systems. Acoustic emission (AE) monitoring is a non-destructive method sensitive to microstructural damages such as e.g. fiber breakage, and matrix cracking in COPVs. This study proposes a novel approach for damage monitoring by integrating acoustic emission techniques with machine learning (ML) algorithms to classify and predict damage types in COPVs. However, training accurate classification models requires extensive labeled datasets, which are very challenging to generate due to the nature of AE signal data and the lack of in-situ observations of microscopic failures in COPVs. Our research overcomes this limitation by automating the labeling process of AE signal data for different COPVs using unsupervised ML methods. The most representative features were extracted and then selected from recorded AE signals. Different unsupervised clustering algorithms were utilized based on various extracted feature combinations. The most stable clustering result was achieved and later used as appropriate labels for training classification algorithms. A deep neural network-based deep learning (DL) architecture was used to train discriminative models on AE data, identify patterns, and classify damage types into different classes with improved accuracy and speed for each COPV. Results demonstrate the potential of the proposed combined deep learning approach to train predictive models in identifying failure patterns. The trained models based on individual COPVs show high training, validation, and test accuracy for unseen datasets and offer enhanced predictive capabilities by following advanced DL techniques compared to traditional monitoring methods. The proposed method highlights its potential to improve the efficiency and safety of hydrogen storage systems. T2 - SCHALL 25 CY - Dresden, Germany DA - 26.03.2025 KW - Sequential Neural Network KW - Acoustic Emission KW - Composite Overwrapped Pressure Vessels KW - Damagemonitoring KW - Machine Learning KW - Deep Learning KW - Deep Neural Network PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-629040 DO - https://doi.org/10.58286/30958 SP - 1 EP - 12 AN - OPUS4-62904 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Epple, Niklas A1 - Sanchez Trujillo, Camila A1 - Fontoura Barroso, Daniel A1 - Hau, Julia A1 - Niederleithinger, Ernst ED - Lienhart, Werner ED - Krüger, Markus T1 - Monitoring of Concrete Infrastructure with Active Ultrasound Coda Wave Interferometry N2 - Coda Wave Interferometry has been used in Geophysics to detect weak changes in scattering media. Past research in Structural Health Monitoring has shown that this methodology can be applied to concrete structures to detect material changes by calculation of relative velocity changes. Successive measurements with embedded ultrasonic transducers provide a repeatable signal for reliable long-term monitoring of concrete. To research the application in real-world structures, we have embedded ultrasonic transducers in a bridge in Ulm and a Metro station in Munich, Germany. This study gives an overview of the monitoring of these two structures. The results show the potential and challenges of the method. Data evaluation can be largely automated to gain insights into material changes and other influences on the structure, such as traffic-induced load and temperature variations. The experiments demonstrate the ease of installation, longevity of the sensor installation, and sensitivity of the measurement technique, but highlight problems with the application, especially if electromagnetic noise affects data quality. As no confirmed substantial damage was recorded during the monitoring period on both structures, we evaluate load tests to investigate the effect of static load on the structures and the coda monitoring results. The experiments show that the influence of load can be detected, even if the temperature influence is not removed from the data. This indicates that online damage detection with coda monitoring is possible, but further research on damage detection in real-world structures has to be conducted to confirm laboratory findings. T2 - 13th International Conference on Structural Health Monitoring of Intelligent Infrastructure CY - Graz, Austria DA - 01.09.2025 KW - Active Ultrasound Measurements KW - Coda Wave Monitoring KW - Embedded Transducers PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-640582 DO - https://doi.org/10.3217/978-3-99161-057-1-012 SP - 45 EP - 51 PB - Technische Universität Graz CY - Graz AN - OPUS4-64058 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Marquardt, Raphael A1 - Biegler, Max A1 - Rethmeier, Michael T1 - Influence of laser power on the melt pool shape of handheld laser beam welding of 1.5 mm thick micro alloyed steel N2 - Manual welding of structures requires highly skilled welders due to the large heat-affected zone of arc-based processes, that can negatively impact microstructure and cause distortion. Handheld laser beam welding is a promising alternative with high welding velocity and a concentrated heat input. However, its current use in industry is limited to parts with aesthetic requirements, often made of high-alloyed steel. To extend the use of handheld laser beam welding to low-cost steels with good mechanical properties, this study investigates the influence of laser power on the melt pool shape for micro-alloyed steel with a thickness of 1.5 mm. Tested joint geometries are T-joints welded with filler wire as well as butt joints and overlap joints without filler wire, which are typically found in assemblies under mechanical load. Weld quality is assessed by weld porosity analysis. The results show that the handheld laser beam welding with filler wire produces T-joints with a very good external appearance, but with porosity between level C and D in the cross sections according to DIN EN ISO 13919-1. By increasing the laser power, a deep penetration of the T-joint zone can be achieved without increasing the actual throat thickness. For handheld laser beam welding of butt joints a full penetration weld of the highest quality class can be reached. Overlap joints can be welded with full or partial penetration depending on the laser power selected, with quality classes between B and C in terms of porosity. T2 - 20th Nordic Laser Materials Processing Conference CY - Kongens Lyngby, Denmark DA - 26.08.2025 KW - Hand held laser welding KW - Laser beam welding KW - Low alloyed steel KW - Process parameter PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-641671 DO - https://doi.org/10.1088/1757-899X/1332/1/012015 SN - 1757-899X VL - 1332 SP - 1 EP - 6 PB - Institute of Physics CY - London [u.a.] AN - OPUS4-64167 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Wang, Kun A1 - Lu, Xin A1 - Schukar, Marcus A1 - Hicke, Konstantin T1 - Water absorption effects on distributed temperature sensing using polyimide-coated optical fiber N2 - Polyimide-coated fibers are becoming more popular for distributed temperature sensing (DTS) because this coating can withstand much higher temperatures than the standard acrylate coating. As a hygroscopic material, polyimide can absorb water from the air, changing its properties, which may result in a modified temperature response of the sensing fiber. This study investigates the effect of water absorption on the performance of polyimide-coated optical fibers with different sizes and properties. The thermal response of these fibers was determined experimentally from 20°C to 90°C at a broad relative humidity level ranging from 10% to 90%. The results show that all the fibers experienced a decrease in temperature sensitivity as humidity increased, with the most noticeable non-linear spectral shift observed at higher humidity levels. These findings highlight the importance of optimizing fiber design and coating properties to balance stability and sensitivity, ensuring the reliable performance of DTS systems under extreme environmental conditions. T2 - 29th International Conference on Optical Fiber Sensors CY - Porto, Portugal DA - 26.05.2025 KW - Humidity sensing KW - Distributed temperature sensing KW - Optical fiber sensors KW - Temperature sensing KW - Water absorption KW - Polyimide-coated fiber PY - 2025 SN - 978-1-5106-9187-2 DO - https://doi.org/10.1117/12.3062748 VL - 13639 SP - 136393W-1 EP - 136393W-4 PB - SPIE AN - OPUS4-63642 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Lu, Xin A1 - Schukar, Marcus T1 - Humidity response analysis of optical fibers with hygroscopic coatings based on Lamé’s equations N2 - Optical fibers with hygroscopic coatings are widely used for humidity sensing, where the coating expands upon absorbing water, inducing strain in the fiber. This strain is then used to determine humidity. However, previous studies have oversimplified the strain generation process. A comprehensive three-dimensional model of the mechanical interaction between the coating and the fiber is built based on Lamé’s equations. An analytical expression for the induced strain is derived. The proposed model predicts larger humidity-induced strain compared to the reported ones, given the same Young’s modulus or coefficient of humidity expansion for the coating. Interestingly, the effect of coating thickness on strain response are quite similar for both methods. Experimental validation using fibers with a polyimide coating shows strong agreement with the theoretical predictions. T2 - 29th International Conference on Optical Fiber Sensors CY - Porto, Portugal DA - 26.05.2025 KW - Reflectometry KW - Distributed fiber sensing KW - Humidity sensors KW - Lamé’s equations KW - Optical fiber sensors KW - Structural health monitoring KW - Rayleigh scattering PY - 2025 SN - 978-1-5106-9188-9 DO - https://doi.org/10.1117/12.3060891 VL - 13639 SP - 1 EP - 4 PB - SPIE AN - OPUS4-63257 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Lu, Xin A1 - Hicke, Konstantin T1 - Polarization-diversity-detection-based wavelength-scanning coherent-optical-time-domain reflectometer and its application for bus monitoring N2 - Although wavelength scanning coherent optical time-domain reflectometry (WS-COTDR) system is immune to fading effect, it suffers from occasional and localized large errors caused by the false peak in the correlation spectrum due to the large signal generated in the random interference of the backscattered light. Polarization diversity detection is applied to a standard WS-COTDR system to suppress large measurement errors. In this way, the orthogonally polarized components of backscattered light can be obtained and processed separately. Due to the birefringence of the sensing fiber, the components experience different interference processes, so the average of their correlation spectrum can suppress the false peaks and finally reduce the occurrence of larger errors. The effectiveness of the proposed method is validated in laboratory for monitoring of sinusoidal vibrations and in field for tracking the bus movement via a dark fiber. T2 - 29th International Conference on Optical Fiber Sensors CY - Porto, Portugal DA - 26.05.2025 KW - Traffic monitoring KW - Coherent optical time domain reflectometry KW - Distributed fiber sensing KW - Polarization diversity detection PY - 2025 SN - 978-1-5106-9187-2 DO - https://doi.org/10.1117/12.3060889 VL - 13639 SP - 1 EP - 4 PB - SPIE AN - OPUS4-63258 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schubert, Sven A1 - Neumann, Martin A1 - Reichardt, Adrian A1 - Komann, Steffen A1 - Wille, Frank T1 - Experiences with the implementation of ageing management for packages for transport of radioactive materials in Germany N2 - The consideration of ageing mechanisms is now obligatory for the design of transport packages with integration of the para 613A into IAEA SSR-6 (Rev. 1). In addition, para 809(f) of SSR-6 (Rev. 1) requires for packages intended to be used for shipment after storage the consideration of the effects of ageing mechanisms during storage in safety analyses and the implementation of corresponding instructions for operation and maintenance. Para 503(e) requires that these packages have been maintained during storage in a manner that all requirements specified in SSR-6 (Rev.1) and in the applicable certificates of approval have been fulfilled. The evaluation of ageing mechanisms and their effects including monitoring are part of BAM’s authority assessment tasks related to the mechanical and thermal package design and quality assurance aspects. BAM has compiled the guideline BAM-GGR 023 for the implementation of ageing assessment and related measures into the approval procedure. The implementation of ageing management measures is obligatory in case of extension/renewal of package design approval certificates. BAM has evaluated package designs which are used only for transport as well as package designs for long term interim storage. The assessment of ageing mechanisms associated with the identification of ageing effects on components is the main part of the ageing management plan (AMP). Different approaches regarding AMP structure are introduced. Experiences and approaches about the evaluation of components for the expected package operating time are shown. We are focusing the evaluations of proofs for not accessible and not replaceable components. Operational experiences for these package designs are available and should be considered in the ageing evaluation. Corresponding measures for package monitoring are to be derived based on these results. The measures for monitoring shall be fixed in the Ageing Surveillance Program (ASP) to maintain a specification conform package for the transport on public routes. We show exemplary how results from ageing evaluation during the approval procedure are transferred into the ASP. T2 - PATRAM 2025 CY - San Antonio, Texas , US DA - 27.07.2025 KW - RAM KW - Ageing management KW - Radioactive material KW - Transport PY - 2025 SP - 1 EP - 8 PB - INMM CY - Washington D.C. AN - OPUS4-63987 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Neumann, Martin A1 - Feldkamp, Martin A1 - Linnemann, Konrad A1 - Wille, Frank T1 - Conclusions from the first return campaign of vitrified High-Level Waste on sea going vessels from the competent authority N2 - Germany has to take back vitrified waste from the reprocessing plants in France and Great Britain. The waste resulted from decades of transporting spent fuel for reprocessing to La Hague and Sellafield. The return campaign from France was concluded in 2024 with the transport of five CASTOR® HAW28M casks to the interim storage facility in Philippsburg in southern Germany. The return of waste from Sellafield comprises three campaigns and a total of 20 CASTOR® HAW28M casks. The first campaign was performed in 2020, consisting of six CASTOR® HAW28M casks, while the second campaign was performed in March 2025, consisting of seven CASTOR® HAW28M casks. The casks were transported by rail from Sellafield to the port in Barrow-in-Furness, where they were loaded into a dedicated seagoing vessel, certified as INF Class 3 according to the INF Code. This was the first time that vitrified high level waste with considerable heat load was transported under a German design approval certificate. The third campaign is expected to be performed during 2026. BAM as part of the German competent authority system was among others involved in the assessment of the sea transport. BAM required for the first transport, among others, an assessment of temperature distribution during transport, logging of temperatures of cargo bays and graphical imaging of temperatures of the bay with the cask to ensure compliance with temperature specifications, e.g. maximal neutron absorber and gasket temperatures. Special interest was taken in the identification of possible events exceeding the specified temperatures considering the different philosophies of the IMDG code and its supplement the INF code regarding temperature control of hatches. Results show compliance with assumed conditions. T2 - PATRAM 2025 CY - San Antonio, Texas, USA DA - 27.07.2025 KW - RAM KW - Transport KW - Radioactive material KW - Sea PY - 2025 SP - 1 EP - 8 PB - INMM CY - Washington D.C. AN - OPUS4-63984 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Müller, Lars A1 - Scheidemann, Robert A1 - Neumeyer, Tino A1 - Neumann, Martin A1 - Komann, Steffen A1 - Wille, Frank T1 - Thightness Assessment of welded Lids for Encapsulations of damaged Spent Nuclear Fuel in the Design Approval Process of Dual-Purpose Casks (DPC) N2 - The disposal of spent nuclear fuel in Germany is ensured using dual-purpose casks (DPC) for transport and interim storage. The leak tightness of the DPC and resulting containment is one of the most important aspects. Additional encapsulations are required for damaged spent nuclear fuel (DSNF) to guarantee safe handling and a separate tight closure. Due to the general design of DPCs for standard fuel assemblies should special requirements be considered for the design of the encapsulations for DSNF to ensure the loading in existing package designs. The absence of a replaceable sealing in the tightness barrier is the main difference for the encapsulations for damaged spent nuclear fuel. Instead, they are welded shut with a lid. The leak tightness of the encapsulation shall be proven in the design approval process for all transport conditions. This is especially valid for accident conditions of transport, where high internal impact forces may occur. BAM as German competent authority is responsible for the safety assessment of mechanical and thermal design, retention of radioactive material and quality assurance aspects of manufacturing and operation. BAM carried out a comprehensive safety assessment concerning the mechanical package design. As there are no representative standards for verifying the leak tightness of a welded lid, two approaches were being pursued. Established German standards may be used for verifying the leak tightness of a weld - but limited to low stresses. Therefore, physical tests were required for higher impact loads. Representative drop tests and highly sensitive leakage tests were performed. The paper presents an overview of the containment assessment by BAM and points out the main findings for the design of welds regarding leak tightness. Both verification procedures are described, on one hand with German standards for lower loads and on the other hand with physical tests for higher impact loads. The leak tightness of the encapsulation weld could be approved based on leakage tests and a corresponding evaluation for all transport conditions. T2 - PATRAM 2025 CY - San Antonio, Texas, USA DA - 27.07.2025 KW - Transport packages KW - Tightness assessment KW - Welded lids KW - Encapsulations PY - 2025 VL - 2025 SP - 1 EP - 11 PB - Institute of Nuclear Materials Management (INMM) CY - Indianapolis AN - OPUS4-64023 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Guitton, Matthieu A1 - Chrupek, Thierry A1 - Leblanc, Vincent A1 - Van derTuijn, Jeroen A1 - Kaufhold, Dominik A1 - Kesting, Frederik A1 - Müller, Lars T1 - Multilateral approval of a SCO-III (three spent steam generator lower parts from EDF Fessenheim nuclear power plant) multimodal shipment N2 - A Surface Contaminated Object (SCO) is defined as a solid object which is not itself radioactive, but which has radioactive material distributed on its surfaces. The 2018 Edition of the IAEA Regulations for the Safe Transport of Radioactive Material (SSR-6 Rev. 1) introduced the group SCO-III to transport unpackaged large objects. The two pressurized water reactors of the Fessenheim Nuclear Power Plant, owned by EDF, were shut down in 2020. Previously, for maintenance operations in the year 2002 and 2010, the three steam generators – over 20 metres long, 300 tons – of each reactor were taken out from the reactors, divided in two and stored on site: - EDF shipped the six upper parts, as SCO-I, to Cyclife, in Studsvik (Sweden), in 2021, to be recycled; - EDF plans two transports of the lower parts (three parts for each transport), as SCO-III (considering the higher activity due to the NPP primary coolant) to the same facility. Modes of transport are, from consignor to consignee, road, inland waterways and maritime. The countries crossed by inland waterways, from Neuf-Brisach to Dunkerque (France), are France, Germany, Belgium and the Netherlands. According to the para. 825 of SSR-6 Rev. 1, “multilateral approval shall be required for the shipment of SCO-III”. EDF has submitted to all Competent Authorities an application (para. 827A of SSR-6 Rev. 1), including a transport plan and demonstrations to withstand normal conditions of transport. Despite SSR-6 Rev. 1, national regulations have their own specificities and each Competent Authority has its own assessment procedures. Nevertheless, involved Authorities agreed for a joint review, which included: - the understanding of national regulatory requirements, - the expected level of detail and quality of the safety case, - the feedback from previous shipments of similar type, - the contents, including the conditions, of the approvals to be issued. This joint review demonstrated good coordination between authorities, enabling the application to be processed rapidly, and the various authorities to benefit from each other's expertise and feedback. This was of particular importance, as it was the first application for the transport of an SCO-III assessed by the Competent Authorities involved. Finally, the authorities were able to issue approvals, whose format is certainly in line with their national provisions, but whose content and level of requirements in terms of transport safety are consistent. T2 - PATRAM 2025 CY - San Antonio, Texas, USA DA - 27.07.2025 KW - Shipment KW - Multilateral approval KW - Steam generator KW - SCO-III PY - 2025 VL - 2025 SP - 1 EP - 8 PB - Institute of Nuclear Materials Management (INMM) CY - Indianapolis AN - OPUS4-64026 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schartel, Bernhard T1 - Fire Retardancy Featuring Sustainability: Food for Thought between Fake Fiction and Future N2 - Sustainability, or in other words, exploiting resources under the terms of environmental conservation for the economic welfare and prosperity continuously over time, would revolutionise the plastics industry were it to become predominant practice as a linear, fossil-fuel–based economy is switched to a carbon circular economy. Food for though is given by dint of a critical overview of the current trends and mainly by sketching our own key projects performed in the field of sustainable flame-retardant polymeric materials in the recent years. T2 - Interflam 2025 CY - London, United Kingdom DA - 30.06.2025 KW - Biocomposites KW - Sustainability KW - Renewable KW - Bio wastefibres KW - Fire Behavior PY - 2025 VL - 1 SP - 187 EP - 190 PB - Interscience Communications Ltd AN - OPUS4-63681 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Stanisavljevic, Mila A1 - Essel, S. A1 - Karbach, N. A1 - Zirzow, Johannes A1 - Hoffmann, T. A1 - Neumann, Patrick P. T1 - Performance Assessment of Methane and Carbon Dioxide Sensors for D rone Based Environmental Gas Monitoring N2 - This study evaluates the performance of methane (CH₄) and carbon dioxide (CO₂) sensors mounted on an unmanned aerial vehicle (UAV) for gas detection in open-field environments. Sensors were tested simultaneously during UAV flights over artificial gas sources, with wind data collected from two anemometers to understand plume dynamics. Field-deployed CH₄ sensors provided validation for the UAV-based measurements. The results demonstrate the sensors' effectiveness in gas detection. T2 - Sensor and Measurement Science International (SMSI) CY - Nuremberg, Germany DA - 06.05.2025 KW - UAV-based gas sensing KW - Sensor comparison KW - Methane and carbon dioxide detection PY - 2025 SN - 978-3-910600-06-5 DO - https://doi.org/10.5162/SMSI2025/B1.3 SP - 77 EP - 78 PB - AMA Service GmbH CY - Wunstorf AN - OPUS4-64038 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Stührenberg, Jan A1 - Häusler, Felix S. A1 - Neumann, Patrick P. A1 - Dragos, Kosmas A1 - Smarsly, Kay ED - Francis, A. ED - Miresco, E. ED - Melhado, S. T1 - Multi-Agent-Based Swarm Gas Source Localization Using Nano Aerial Robots N2 - Gas source localization (GSL) is crucial for mitigating the impact of industrial accidents and natural disasters, for example finding leaks in oil and gas facilities or survivors in collapsed environments. Traditional GSL methods involving human intervention may be hazardous and time-consuming. Utilizing swarms of agile and cost-effective nano aerial robots holds the potential to enhance the safety and efficiency of GSL operations. This study draws inspiration from biological swarms, particularly colonies of social insects, to coordinate and optimize the performance of nano aerial robotic swarms. While most existing swarm GSL strategies assume gas concentration maxima to be in close proximity to actual gas sources, recent research has highlighted the importance of “bouts” as a more precise indicator of gas source proximity, considering the intermittency of gas distributions. In this paper, a swarm GSL strategy is introduced that incorporates bouts as indicators of source proximity, complemented by a bio-inspired pheromone communication system. Specifically, nano aerial robots are deployed as autonomous agents. Upon detecting bouts, the agents emit pheromone markers in an artificial environment, mimicking social insects. Using the concept of artificial potential fields, the agents either exploit the search space by following pheromone gradients or explore the search space. The proposed swarm GSL strategy is implemented and validated in a real-world experiment, conducted in an indoor environment with a single gas source. The experimental results demonstrate the capability of the swarm GSL strategy to perform effectively in indoor environments and that the intermittency of gas distributions is a better source proximity indicator than the mean concentration. It is concluded that this research may provide a methodological basis for improving gas source localization techniques and enhancing disaster response capabilities. T2 - ICCCBE 2024 CY - Montreal, Canada DA - 25.08.2024 KW - Gas source localization KW - Nano aerial robots KW - Mobile robotic olfaction KW - Bouts KW - Swarm robotics PY - 2025 SN - 978-3-031-87363-8 SN - 978-3-031-87364-5 DO - https://doi.org/10.1007/978-3-031-87364-5_28 SN - 2366-2557 VL - 2025 SP - 337 EP - 346 PB - Springer Nature Switzerland CY - Cham AN - OPUS4-63416 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Gleim, Tobias ED - Monavari, Mehran ED - Bertovic, Marija ED - Wille, Frank T1 - AI-Based Documentation Analysis for Safety Assessment of Packages for Radioactive Material N2 - The transportation of radioactive material requires, dependent on type and quantity of the radioactive material, a regulatory approval based on the package type. Safety assessments shall be conducted in compliance with the International Atomic Energy Agency (IAEA) regulations and documented in a comprehensive package design safety report to obtain approval from authority. This comprehensive safety report evaluates a broad range of requirements from the regulations, including mechanical, thermal, shielding, criticality and transport requirements and controls, and testing assessments. Additionally, it encompasses supporting documents such as specifications, inspections, certifications, drawings, and guidelines in a variety of complex documents. Safety and manufacturing reports contain multiple interconnected sub-reports covering various topics. Changes, such as component modifications, material property updates, or regulatory revisions, often impact multiple sections of the safety analysis reports, making even minor adjustments complex and time-consuming. Each transport package has unique requirements to be fulfilled, making every safety report distinct, despite following the same regulatory framework. Most documentation exists in standard digital formats but is often not machine interpretable, preventing automated analysis of the critical dependencies between them. This paper argues that moving beyond simple digitization towards structured knowledge representation is essential for addressing these challenges. We propose a multi-stage approach, beginning with foundational AI technologies such as Large Language Models (LLMs) and Retrieval-Augmented Generation (RAG), and progressing toward the construction of Knowledge Graphs (KGs). KGs convert unstructured and semi-structured information into a connected, queryable network, enabling precise tracing and visualization of complex interdependencies within the documentation landscape. By linking interpretable content directly to datasheets, tables, simulations, experimental results, standards, and regulations, such a system would automatically identify changes and interdependencies. Related conditions could be validated using AI-based tools, reducing the need for manual intervention, improving both efficiency and safety. Human error plays a significant role in drafting, reviewing, and revising safety reports, often requiring iterative review cycles and multiple reviewers before approval. A digital quality infrastructure could reduce iterations and further improve efficiency. Integrating AI into this process could optimize safety assessments and enhance their robustness by leveraging interpretability to enhance safety. This preliminary study explores the readiness and requirements for using intelligent documentation analysis system in the context of regulatory compliance for package safety for the transport of radioactive material. By analysing current documentation workflows, we identify how LLM-based tools can interpret complex safety reports and highlight critical interdependencies and then demonstrate why a KG-based architecture is necessary to robustly manage and query critical interdependencies. This lays the groundwork for future agentic AI systems capable of proactively supporting the safety assessment lifecycle, while stressing the importance of robust data governance and AI reliability in this highly regulated context. T2 - PATRAM 2025 CY - San Antonio, TX, USA DA - 27.07.2025 KW - AI, RAG, LLM, Knowledge Graph PY - 2025 SP - 1 EP - 10 PB - Institute of Nuclear Materials Management (INMM) AN - OPUS4-63863 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Naster, Maximilian A1 - Gleim, Tobias A1 - Wille, Frank T1 - Experimental and numerical analyses of hydrogen flames for the thermal testing of transport packages for radioactive material N2 - In this paper we present an update of the hydrogen based test rig for an ongoing feasibility study of using hydrogen as an energy source for the thermal testing of transport packages containing radioactive materials [ The test rig is capable of combusting hydrogen for a wide range of different burner geometries, mass flows , hydrogen blends and single jet flame operation s as well as a full array of burners for thermal testing can be set up. As this type of fire test according to the IAEA boundary conditions does not yet exist, a large number of preliminary investigations, safety assessments and simulations must be carried out in order to develop a viable concept for hydrogen fires. In a first step of the feasibility study, the temperature , structure, and radiative behavior of hydrogen jet flames must be surveyed. The simulation with a single hydrogen flame was investigated in a previous work. In the next step the results are used to study the interaction and structural behavior of multiple jet flames in proximity with varying nozzle distances. With the test rig completed, it will be possible in future works to design burner frames suitable for fire reference tests to make comparisons with pool and propane fires used in assessment procedure today. Thus, preliminary comparative numerical simulations are conducted to model the behavior of overlapping hydrogen jet flames using the software package Ansys®. This paper gives an overview on the current state and design of the test rig. Furthermore, the results of the simulations show that nozzle geometry, mas s flow and nozzle distance provide significant design margin for designing a test fire capable of fully engulfing a specimen. T2 - PVP2025, Pressure Vessels & Piping Conference CY - Montreal, Quebec, Canada DA - 20.07.2025 KW - Computational Fluid Dynamics (CFD) KW - Fire testing KW - Hydrogen KW - IAEA PY - 2025 SP - 1 EP - 10 AN - OPUS4-63864 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Affagard, Jean-Sebastien A1 - Gleim, Tobias A1 - Louis, Baptiste A1 - Quercetti, Thomas A1 - Ledroit, Frédéric A1 - Létang, Eric T1 - Towards a simplifiedmodel of the delayed impact: numerical and experimental outlook N2 - The IAEA Regulations for the Safe Transport of Radioactive Material No. SSR-6 require drop tests for demonstrating the ability of a package to withstand accident conditions of transport. In case a gap exists between the contents and the lid, it can result in a delayed impact of the content onto the lid system during a vertical drop test. The kinematic energy transmitted to the lid in such cases can be significant due to the stiffness of the impact, leading to high stresses in the bolts compared to a configuration without a gap. In the past, IRSN and BAM have individually investigated the modelling of the delayed impact phenomenon. BAM has examined the effects of the delayed impact phenomenon for spent fuel packages in a comparative analysis between experiments and simulations, which was presented at SMIRT 2013. Meanwhile, IRSN’s has developed a simple numerical tool that can quickly evaluate the influence of various parameters before considering a more complex finite element numerical calculation. This tool was presented at PATRAM 2022. In 2023, BAM and IRSN (now ASNR - French nuclear safety and radiation protection authority) decided to jointly pursue their study on the delayed impact phenomenon, incorporating damping effects, by developing new insights and techniques. To this end, a controlled and simplified set of experiments needs to be developed to calibrate and validate the simplified model. These experiments will record velocity, position of parts, strain and accelerations. The parameters and the configurations necessary for the development of the mock-up, as well as the placement and quantity of sensors, are determined through extensive pre-calculations using both complex finite element models and the simplified approach. A key challenge involves precisely controlling the drop of the mock-up to accurately replicate the theoretical contact and damping conditions. Advanced sensor technologies will be employed to acquire reliable and sufficient data. The tests are designed and conducted at BAM's TTS drop test facility in collaboration with ASNR. T2 - PATRAM 2025 CY - San Antonio, TX, USA DA - 27.07.2025 KW - Experiments KW - Impact KW - Drop Tower PY - 2025 SP - 1 EP - 11 CY - Institute of Nuclear Materials Management (INMM) AN - OPUS4-63870 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -