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 - TY - CONF A1 - Quercetti, Thomas A1 - Feldkamp, Martin A1 - Gleim, Tobias A1 - Musolff, André A1 - Werner, Jan A1 - Wille, Frank T1 - Fire Test Stand for Thermal Testing of Large Packages for the Transport of Radioactive Materials N2 - Packages for the transport of high level radioactive materials are designed to withstand severe accidents. These packages must comply with the specific safety requirements SSR 6 [ of the International Atomic Energy Agency (IAEA). To guarantee compliance with these requirements, specific mechanical and thermal tests need to be addressed r egard ing the package type. Typically, the r egulations prescribe mechanical tests followed by a thermal test as part of a cumulative test scenario. The thermal test is specified by the exposure of a test specimen for a period of 30 minutes to a thermal environment that provides a heat flux equivalent to that of a hydrocarbon fuel air fire with an av erage fire temperature of at least 800 °C fully flame engulfing the test specimen. The Federal Institute for Materials Research and Testing (BAM) operates various test facilities for this purpose at their Test Site for Technical Safety (near Berlin in Germany). Thermal tests for large packages are conducted in an established fire test stand that may be adapted by the test setup to the geometric boundary conditions of a test specimen. This fire test stand is built for test specimens with masses up to 200,000 kg an d geometric dimensions relating to large transport packages including their impact limiters. The test specimen is usually placed on a water cooled support frame in the middle of the test stand. The fire is realized by burning propane gas which is released in liquid state from an array of gas nozzles arranged in the form of a burner ring surrounding the test specimen. For particularly extra large test specimens, two burner rings are used on top of each other and at different heights to firstly achieve full f ire engulfment with a significantly larger volume of fire and secondly to achieve the required heat output , cf. In advance of a regular thermal test BAM usually performs so called fire reference tests to determine the test conditions for compliance with the IAEA requirements. These tests are performed using a generic package which corresponds to the external geometr ic dimensions of the test specimen used later in the approval test. Then, this reference package is exposed to a fire under defined test parameters whereas the corresponding heat input determined from the temperature changes measured is regarded as main cr iterion for proofing compliance with the IAEA criteria. The paper shows the experimental proof of the suitability of BAM’s fire test stand for thermal testing of extra large packages. The heat input and fire temperatures fully meet the IAEA criteria and can also be set significantly higher for example for extra regulatory testing. T2 - PATRAM 2025 CY - San Antonio, TX, USA DA - 27.07.2025 KW - IAEA Regu-lations KW - Fire Test Stand KW - Accident Scenario KW - Fire Qualification PY - 2025 SP - 1 EP - 10 CY - Institute of Nuclear Materials Management (INMM) AN - OPUS4-63872 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Komann, Steffen A1 - Müller, Lars A1 - Neumann, Martin A1 - Wille, Frank T1 - Shipment of SCO-II – Authority assessment of mechanical aspects and quality management N2 - The decommissioning of nuclear facilities necessitates either the storage or disposal of large radioactive components such as steam generators, pressurizers, reactor pressure vessels and heads, or coolant pumps. These components or objects are large in size and mass with up to 6 meters in diameter and 20 meters in length and a weight of up to 400 tons. They are often transported to a storage, disposal, or recycling facility. Large components from nuclear facilities may often not be packed and need to be transported unpackaged due to size and weight. T2 - PATRAM 2025 CY - San Antonio, TX, USA DA - 27.07.2025 KW - radioaktive Stoffe, Rückbau kerntechnischer Anlagen, Transport, Gefahrgut PY - 2025 SP - 1 EP - 10 AN - OPUS4-63878 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Zencker, Uwe A1 - Simbruner, Kai A1 - Völzke, Holger T1 - Analysis of Zirconium Hydride Structures in Spent Fuel Claddings Subjected to Storage Conditions N2 - Pre-storage drying and the early stage of storage can subject spent fuel claddings to higher temperatures and higher tensile hoop stresses than those associated with in-reactor operation. Under these conditions, existing circumferential hydrides in zirconium-based alloys can be partly reoriented into radial ones that may result in embrittlement of the cladding material. As a consequence, the failure limits may be reduced under mechanical loads caused by handling or during transport after storage. The potential occurrence of brittle fracture strongly depends on the specific location, size, and orientation of the zirconium hydrides. The morphology of such hydride structures was experimentally investigated in unirradiated, hydrogen-loaded samples made of a zirconium-based alloy. The hydrogen was introduced into the cladding sample by means of a cathodic charging process. The loading process was followed by a thermal treatment to precipitate the hydrides in the circumferential direction and then a thermomechanical treatment to reorient the hydrides in the radial direction. Metallographic methods were used to describe and classify the hydride morphology. The resulting metallographic micrographs were evaluated using suitable radial hydride metrics. The determination of the maximum length of a hydride structure was carried out in two different ways, each with its own advantages and disadvantages. Both methods consider neighboring hydrides as continuous according to the definition of the Radial Hydride Continuity Factor (RHCF). The first option is to measure the Euclidean distance between the two most distant pixels of the hydride structure in the image analysis, whereby the actual maximum size of the hydride structure is determined. The second possibility is to measure the maximum size of a hydride or a hydride structure within a certain arc length in the radial direction of the cladding tube. This value is of particular interest because the ratio of the maximum radial size of a hydride structure to the wall thickness of the cladding tube is used for the safety assessment of spent fuel claddings with radial hydrides using the RHCF. T2 - 21st International Symposium on the Packaging and Transportation of Radioactive Materials - PATRAM 2025 CY - San Antonio, TX, USA DA - 27.07.2025 KW - Extended Interim Storage KW - Nuclear Fuel Cladding KW - Zirconium Hydride Structure KW - Ring Compression Test KW - Micrograph Analysis PY - 2025 SP - 1 EP - 8 CY - Indianapolis, IN, USA AN - OPUS4-63875 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Popiela, Bartosz A1 - Schukar, Marcus A1 - Breithaupt, Mathias A1 - Günzel, Stephan A1 - Mair, Georg W. A1 - Krebber, Katerina A1 - Seidlitz, Holger T1 - Embedding of Fiber Optic Sensors Under Industrial Conditions and Distributed Strain Sensing in Type 4 Composite Pressure Vessels N2 - The number of in-operation composite pressure vessels is increasing, partly due to their attractiveness for on-board compressed gas storage and transport applications. A possible way to maintain the highest safety levels is through the structural health monitoring of the composite cylinders. Here, the use of fiber optic sensors appears to be a promising approach. However, the integration of the optical fibers into the composite structure of a pressure vessel has been shown to be challenging. In this study, insights on the embedding of optical fibers in the composite structure under industrial conditions are provided. A protection concept for the ingress and egress of the optical fibers is presented. Finally, the results from destructive slow burst tests are evaluated, showing no clear trend in the impact of the embedded optical fibers on the performance of composite pressure vessels. T2 - 24th International Conference on Composite Materials CY - Baltimore, Maryland, USA DA - 04.08.2025 KW - Composite KW - Pressure vessel KW - Filament winding KW - Fiber optic sensors PY - 2025 SP - 3710 EP - 3717 AN - OPUS4-63886 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kemmler, Samuel A1 - Cuéllar, Pablo A1 - Rettinger, C. A1 - Köstler, H. T1 - A Fluid-Solid Coupled Micromechanical Simulation for the Analysis of Piping Erosion During the Seabed Installation of a Suction Bucket Foundation N2 - Suction buckets are a promising concept for the foundations of offshore wind turbines. During the installation process of a suction bucket, localized fluidization of the granular soil, so-called piping erosion, may lead to installation failure. A 3D fluid-solid coupled micromechanical simulation is presented to study the occurrence of piping. An Euler-Lagrangian coupling employs momentum exchange between the fluid phase and the geometrically resolved particles. We investigate the behavior of the soil for three cases with varying prescribed suction velocities. We observe piping in the case with the highest suction velocity by analyzing the deformation of the granular fabric and monitoring the differential pressure. The grains under the bucket wall-tip show the highest hydraulic gradients and forces at the onset of piping. This approach permits a detailed analysis of piping phenomena and brings novel insights on the triggering conditions for piping failure of suction-aided foundations. T2 - TC 105 International Symposium CY - Grenoble, France DA - 23.09.2024 KW - Micromechanical simulation KW - Piping erosion KW - Suction bucket foundation PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-629461 DO - https://doi.org/10.1088/1755-1315/1480/1/012024 SN - 1755-1307 VL - 1480 IS - 1 SP - 1 EP - 4 PB - IOP Publishing AN - OPUS4-62946 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Feldkamp, Martin A1 - Gleim, Tobias A1 - Quercetti, Thomas A1 - Wille, Frank T1 - Evaluation of Convective Heat Transfer Coefficients with CFD for Heat Flux Calculation in Combustion Chamber N2 - Packages for the transport of high-level radioactive waste are designed to withstand severe accidents. To obtain approval for transport, these packages must adhere to the specification-based criteria of regulations established by the International Atomic Energy Agency (IAEA). To ensure compliance with the regulations, mechanical and thermal tests need to be conducted regarding the package type. The requirements define mechanical tests followed by a thermal test, including criteria ensuring the package design’s ability to withstand severe accidents. Heavy-weight packages for the safe transport of radioactive materials are equipped with impact limiters, which are often built with porous materials such as densely packed wood reinforced by steel sheet structures. These components absorb the kinetic energy during the impact of the package in drop tests and thus dampen the acceleration of other package components which supports the package to meet the requirements of the IAEA regulations. Following the mechanical tests, the package must, with its predamaged impact limiters, endure a thermal test defined precisely in the IAEA regulations. The thermal test is defined as a 30-min, fully engulfing 800 °C fire and a following time under ambient conditions for a sufficient period to ensure that temperatures in the specimen decrease in all parts of the specimen. During and following the thermal test, the specimen shall not be artificially cooled, and any combustion of materials of the specimen shall be permitted to proceed naturally. A wood-filled impact limiter can continue to release thermal energy during an ongoing combustion process, thus defining relevant package temperatures. Heat flux from a potentially burning impact limiter to the package is important for the safety evaluation of transport packages. A test setup was developed to approach the energy flow investigation and examine the combustion behaviour of porous materials encapsulated in predamaged cylindrical metal enclosures under various conditions. The setup consists of a combustion chamber for thermal tests under adjustable and defined boundary conditions. The temperature development of the test specimens can be observed from outside using a thermographic imager with high-definition cameras, and the mass loss of the test specimen can be measured in the combustion chamber. Convective heat transfer coefficients for various boundary conditions must be defined for use with experimentally gathered test specimen surface temperature data for heat flux evaluations. The airflow conditions in the combustion chamber were analysed using computational fluid dynamics (CFD) calculations in OpenFOAM with respect to the convective heat transfer coefficients at the surface of a hot test specimen. A convergence study was performed, and sensitivity analyses for different test specimen surface temperatures and exhaust gas volume flows were conducted. T2 - ASME PVP2025, Pressure Vessels & Piping Conference CY - Montreal, Quebec, Canada DA - 20.07.2025 KW - Heat Transfer KW - Convection KW - OpenFOAM KW - Combustion PY - 2025 SP - 1 EP - 7 PB - American society of mechanical engineers (ASME) AN - OPUS4-63901 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Quercetti, Thomas A1 - Feldkamp, Martin A1 - Gleim, Tobias A1 - Musolff, Andre A1 - Werner, Jan A1 - Wille, Frank T1 - A fire test stand for thermal testing of extra-large packages N2 - Packages for the transport of high-level radioactive materials are designed to withstand severe accidents. These packages must adhere to the specification-based criteria of the International Transport Regulations of the International Atomic Energy Agency (IAEA). To ensure compliance with these requirements, specific mechanical and thermal tests need to be addressed with respect to the package type. Typically, the Regulations prescribe mechanical tests followed by a thermal test as part of a cumulative test scenario. The thermal test is specified by the exposure of a test specimen for a period of 30 minutes to a thermal invironment that provides a heat flux equivalent to that of a hydrocarbon fuel-air fire with an average fire temperature of at least 800 °C fully flame engulfing the test specimen. The Federal Institute for Materials Research and Testing (BAM) operates various test facilities for this purpose at their test site (TTS) near Berlin in Germany. Thermal tests for large packages are carried out in an established fire test stand that can be adapted by the test-setup to the geometric boundary conditions of a test specimen. This fire test stand is built for test specimens with masses up to 200,000 kg and geometric dimensions relating to large transport packages including their impact limiters. The test specimen is usually placed on a water-cooled support frame in the middle of the test-stand. The fire is realized by burning propane gas which is released in liquid state from an array of gas nozzles arranged in the form of a burner ring surrounding the test specimen. For particularly extra-large test specimens, two burner rings are used on top of each other and at different heights in order to firstly achieve full fire engulfment with a significantly larger volume of fire and secondly to achieve the required heat output. In advance of a regular thermal test BAM usually performs so-called fire reference tests to determine the test conditions for compliance with the IAEA requirements. These tests are performed using a generic package which corresponds to the external geometric dimensions of the test specimen used later in the approval test. Then, this reference package is exposed to a fire under defined test parameters whereas the corresponding heat input determined from the temperature changes measured is regarded as main criterion for proofing compliance with the IAEA criteria.The paper shows the experimental proof of the suitability of BAM’s fire test stand for thermal testing of extra-large packages. The heat input and fire temperatures fully meet the IAEA criteria but can also be set significantly higher for e.g. extra-regulatory testing. T2 - ASME PVP 2025 CY - Montreal, Quebec, Kanada DA - 20.07.2025 KW - Test stand KW - Thermal testing KW - Package KW - Fire PY - 2025 SP - 1 EP - 6 AN - OPUS4-63892 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Chaudhuri, Somsubhro A1 - Purayil, Sruthi Krishna Kunji A1 - Kruse, Julius A1 - Madia, Mauro A1 - Nielsen, Sören T1 - Thermography-Assisted Mechanical Testing of Cold-Spray (AM) Repair N2 - Cold Spray Additive Manufacturing (CSAM) is a solid-state process that is being increasingly used for structural repairs in aerospace and energy sectors. It enables the deposition of dense material at low temperatures by accelerating metal particles to supersonic velocities, thereby reducing thermal distortion. However, the structural integrity of CSAM repairs—particularly at the interface between the deposited layer and the substrate—remains a critical concern. Various post-treatments and characterization methods have been explored to optimize performance. While X-ray Computed Tomography (XCT) is effective for sub-surface inspection, it cannot be applied in situ during mechanical testing. Digital Image Correlation (DIC), a surface-based method, also lacks sub-surface sensitivity. To address this, Infrared Thermography (IRT) was employed alongside DIC during the tensile and fatigue testing of aluminum CSAM-repaired specimens. A cooled IRT camera operating at 200 FPS captured thermal data, with lock-in processing subsequently applied in post-processing. IRT successfully detected early interfacial damage and enabled the tracking of crack propagation, which was later confirmed through fracture surface analysis. This extended abstract presents findings from fatigue tests using IRT. T2 - 18th International Workshop on Advanced Infrared Technology and Applications (AITA 2025) CY - Kobe, Japan DA - 15.09.2025 KW - Thermography KW - Thermografie KW - Thermal stress analysis KW - Cold spray KW - Damage detection PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-642299 DO - https://doi.org/10.3390/proceedings2025129018 VL - 129 IS - 1 SP - 1 EP - 5 PB - MDPI CY - Basel AN - OPUS4-64229 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Chaudhuri, Somsubhro A1 - Krankenhagen, Rainer A1 - Lapšanská, Ivana A1 - Stamm, Michael T1 - WTB-IRT: Modelling and Measurement of Thermal Contrast in Wind Turbine Rotor Blades (WTBs) N2 - The rapid growth of wind energy infrastructure over the past two to three decades has led to an urgent need for advanced non-destructive testing (NDT) methods—both for newly installed wind turbine blades (WTBs) and for ageing components nearing the end of their service life. Among emerging techniques, passive infrared thermography (IRT) offers a promising solution by enabling contactless, time-efficient inspection based on naturally occurring thermal variations. The effectiveness of passive IRT depends on the presence of sufficient thermal contrast to distinguish surface features, subsurface structures, and defects. To better understand the possibility of obtaining such contrast in composite structures such as WTBs, a controlled study was carried out on a blade section exposed to programmed temperature transients in a climate chamber. Infrared measurements were recorded, and the thermal behaviour of the specimen was simulated using finite element models (FEM) in COMSOL Multiphysics 6.3. Although direct validation is limited by measurement uncertainties and transient effects, the comparison provides insight into the capabilities and limitations of FEM in replicating real-world thermal behaviour. This paper focuses specifically on the challenges related to the modelling approach. T2 - 18th International Workshop on Advanced Infrared Technology and Applications (AITA 2025) CY - Kobe, Japan DA - 15.09.2025 KW - Thermography KW - Wind energy KW - Wind turbine rotor blades KW - Windenergie Anlage Rotorblätter KW - FEA PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-642308 DO - https://doi.org/10.3390/proceedings2025129015 VL - 129 IS - 1 SP - 1 EP - 5 PB - MDPI CY - Basel AN - OPUS4-64230 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Seeber, Henrik T1 - Investigation of Shock Wave Propagation in Soft Tissue Simulants: An Analysis of Organic Gelatin and Synthetic Gel N2 - This study investigates the effects of shock waves on soft tissue simulants, focusing on organic gelatin and a synthetic gel. Although extensive research has focused on the mechanical properties of soft tissue simulants, their behavior under shock wave conditions, such as those caused by blasts, is less understood. As explosives are increasingly used in modern combat scenarios, it is essential to study how shock waves interact with soft tissue. This knowledge is crucial for improving protective equipment and evaluating blast effects on the human body. A two-phase methodology was applied: First, organic gelatin production and synthetic gel composition were analyzed, identifying uncertainties and measuring sound speeds at varying temperatures to align with human tissue properties. Second, simulants were subjected to free-field shock waves, and embedded pressure sensors captured wave propagation, peak overpressures, and propagation velocity. Findings provide comparative insights into shock wave responses of simulants, offering a foundation for future experimental setups. KW - Shock wave generator KW - Blast injury KW - Primäre Explosionswirkung KW - Druckwelle PY - 2025 SN - 9781605956978 VL - 34 SP - 63 EP - 79 PB - DEStech Publications Inc. CY - USA AN - OPUS4-63320 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Seeber, Henrik A1 - Grobert, Steffen A1 - Krentel, Daniel T1 - Description of a measurement setup for the combined measurement of LLB exposures in dynamic situations using high-resolution measurement technology N2 - In order to gain an understanding of the Low Level Blast (LLB) exposure of soldiers when using weapon systems, it is necessary to characterize these weapon systems with regard to their overpressure effect [1]. Carrying out static measurements of weapon systems in the rough terrain of firing ranges and training areas poses a challenge for sensitive measurement technology. Furthermore, soldiers are often exposed to LLB in dynamic situations [2]. Therefore, commercially available blast gauges are often used, which, however, are not sufficient for high-resolution measurement of overpressure exposures with academic requirements due to their intended use [3]. Static measurement setups, such as with penile probes, must be used to characterize weapon systems, but they cannot make valid statements about the real load on dynamically behaving soldiers. However, this real load on the soldier is essential in order to be able to adequately assess the potential resulting medical effects. As part of this challenging measurement task, a prototype of a self-sufficient, high-resolution measurement system is presented, which can be used by an operator in dynamic situations without interference. The complete measuring chain was realized as a self-sufficient unit. The system is based on a 20-liter backpack system, which contains the power supply, the measuring amplifier and the measuring card. The measuring computer is attached to the front of the backpack to allow quick access. The measuring system is capable of recording four channels with a sampling rate of up to 2 MHz. Piezoelectric integrated charge pressure sensors are used as a high-resolution pressure sensor (type: PCB138B32). The pressure sensor is placed on a XX- carrier plates with the dimensions XY × YY. The pressure sensors are attached at the typical positions for Blast-Gauges measurements, like on the left shoulder, on the upper chest and on the back of the head. At the same time, commercial blast gauges are placed at the positions of the pressure sensors to qualify the blast gauges (type: B3 Blast Gauges Gen 6). The measuring system is referred to as a “Sensor Carrier Operator (StEk)”. As part of the functional testing of the measurement system, tests are carried out with hand weapons. For this purpose, a soldier is equipped with the StEk and blast gauges. The handguns used are the pistole P8 (caliber 9 mm) and the long rifle G36 (caliber 5.56 mm). The firing position is standing freehand. In addition, the soldier carried out an examination of the carrying comfort of the StEk as part of the training. Furthermore, it was evaluated whether the measuring chain was adequately integrated into the measuring system. The quality of the pressure measurement was also examined, whereby a direct comparison was made with the blast gauges. The measurement system presented here enables the combined (static and dynamic) scientific characterization of weapon systems, particularly with regard to overpressure loading. T2 - Research Specialist Meeting HFM 371 (NATO STO) CY - Toronto, Canada DA - 09.04.2025 KW - Shock wave generator KW - Blast injury KW - Primäre Explosionswirkung KW - Low Level Blast PY - 2025 SP - 1 EP - 8 AN - OPUS4-63322 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Steglich, Patrick A1 - Paul, Martin A1 - Fünning, Tabea A1 - Schumann, Christoph A1 - Mai, Christian A1 - Tannenberg, Robert A1 - Mai, Andreas ED - Cheben, Pavel ED - Čtyroký, Jiří ED - Molina-Fernández, Iñigo T1 - Towards monolithic integration of polymer-based electro-optical devices in silicon photonic integrated circuits using a 250nm 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 - 05.06.2025 KW - Photonic sensors KW - Micro-ring resonator (MRR) KW - Silicon on insulator (SOI) KW - CMOS KW - Local backside etching (LBE) PY - 2025 DO - https://doi.org/10.1117/12.3056280 VL - 13530 SP - 1 EP - 8 PB - SPIE CY - Bellingham, WA , USA AN - OPUS4-63587 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Erxleben, Kjell A1 - Kaiser, Sebastian A1 - Rhode, Michael A1 - Kannengießer, Thomas A1 - Hadick, C. A1 - Schu, K. T1 - Quantification of hydrogen uptake during in-service hydrogen pipeline welding N2 - Hydrogen must be transported on a large scale from producers to consumers to ensure the energy transition. The necessary pipeline grid is achieved by conversion of the natural gas (NG) grid and building new pipelines. Welding during service as part e.g. of “hot-tapping” is unavoidable for maintenance/repair/expansion. Based on existing studies, the basic material compatibility of (low-alloyed) pipeline steels with hydrogen is postulated. However, this cannot be assumed for the case of in-service welding on pipelines in pressurized condition. The reason is the increased temperature e.g. by preheating and (in particular) during welding of the single passes. As a result, the inner pipeline surface undergoes multiple short-term heating but to high temperatures. In particular, the first passes can result in a temperature close to the austenitic transformation of the material for small wall thicknesses. Both increase the hydrogen uptake into the welded joint. If hydrogen embrittlement is likely to occur, depends on the hydrogen uptake, which must be quantified. For this purpose, welding experiments on pressurized demonstrators were conducted. The hydrogen uptake at 100 bar was compared to reference experiments with nitrogen. A new sample extraction routine for the quantification of the weld-zone specific hydrogen uptake was established. Comprehensive experiments with different steels (P235, L360, L485), wall thicknesses (4.1 mm to 7.8 mm) and diameters (DN50 and DN200) were conducted. In addition, the influence of the welding layer sequence on the hydrogen uptake between single- and multi-layer welds was investigated. Analytical approaches were used to approximate the hydrogen uptake in the respective weld zones. The main findings were that the layer sequence and especially the wall thickness have a large influence on the hydrogen uptake. T2 - 20th Pipeline Technology Conference ptc2025 CY - Berlin, Germany DA - 06.05.2025 KW - In-service KW - Hydrogen KW - Pipeline KW - Repair welding KW - component test PY - 2025 SP - 1 EP - 12 AN - OPUS4-63166 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hübner, Martin A1 - Dittmann, Florian A1 - Kromm, Arne A1 - Varfolomeev, Igor A1 - Kannengießer, Thomas T1 - Residual stress reduction using a low transformation temperature welding consumable with focus on the weld geometry N2 - Low transformation temperature (LTT) welding consumables represent an innovative approach to realize compressive residual stress in the weld seam and HAZ. LTT welding consumables use the volume-expanding martensitic phase transformation near room temperature to generate compressive residual stress during cooling. This article focuses on the weld geometry and its influence on residual stress reduction using an LTT welding consumable. For this purpose, layers with an LTT welding consumable were additionally applied to the front sides of conventionally welded longitudinal stiffeners. Different weld geometries of the second weld seam could be realized by varying the welding parameters. These samples were analyzed for geometric parameters, chemical composition, and residual stress. While the chemical composition and martensite start temperature (MS) were only slightly influenced by parameter changes, a clear influence with regard to residual stress and weld geometry was observed. Depending on the shape of the second LTT weld seam, residual stress reductions of 200 to 500 MPa were achieved using the same LTT welding consumable. T2 - IIW Annual Assembly and International Conference CY - Rhodes Island, Dodecanisa, Greece DA - 07.07.2024 KW - Low transformation temperature (LTT) KW - Martensite start temperature KW - Dilution KW - Weld geometry KW - Residual stress PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-633707 DO - https://doi.org/10.1007/s40194-025-02094-3 SN - 1878-6669 SP - 1 EP - 11 PB - Springer Nature CY - Berlin ; Heidelberg AN - OPUS4-63370 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Engelking, Lorenz A1 - Scharf-Wildenhain, R. A1 - Schröpfer, Dirk A1 - Hälsig, A. A1 - Kannengießer, Thomas A1 - Hensel, J. T1 - Influence of heat input on properties and residual stresses in hybrid addi-tive manufacturing of high strength steels using MSG processes N2 - The application of steels with a higher yield strength allows reductions in wall thickness, component weight and production costs. Hybrid additive manufacturing based on Gas Metal Arc Welding (GMAW) processes (DED-Arc) can be used to realise highly effi-cient component modifications and repairs on semi-finished products and additively manufactured structures. There are still a number of key issues preventing widespread implementation, particularly for SMEs. In addition to the manufacturing design, detailed information about assembly strategy and geometric adaptation of the component for modifications or repairs are missing. These include the welding-related stresses associ-ated with the microstructural influences caused by the additive manufacturing steps, particularly in the transition area of the substrate and filler material interface. The pre-sent research focuses the effect of welding heat control during DED-Arc process on the residual stresses, especially in the transition area. Defined specimens were welded fully automatically with a high-strength solid wire (yield strength > 790 MPa) especially adapted for DED-Arc on S690QL substrate. The working temperature and heat input were systematically varied for a statistical effect analysis on the residual stress state of the hybrid manufactured components. Regarding heat control, t8/5 cooling times within the recommended processing range (approx. 5 s to 20 s) were complied. The investiga-tion revealed a significant influence of the working temperature Ti on the compressive residual stresses in the transition area and the tensile residual stresses at the base of the substrate. High working temperatures result in lower compressive residual stresses, heat input E does not significantly affect the tensile stresses. T2 - 6. Symposium Materialtechnik CY - Clausthal-Zellerfeld, Germany DA - 20.02.2025 KW - DED-Arc KW - Residual stress KW - Heat control PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-632188 DO - https://doi.org/10.21268/20250506-3 SP - 110 EP - 122 AN - OPUS4-63218 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kaiser, Sebastian A1 - Erxleben, Kjell A1 - Rhode, Michael A1 - Kannengießer, Thomas T1 - Herausforderungen beim Schweißen im Betrieb an Wasserstoff-Ferngasleitungen N2 - Als Energieträger der Zukunft kommt grünem Wasserstoff große Bedeutung bei der Energiewende und der zukünftigen, nachhaltigen Energieversorgung zu Teil. Zum effizienten und sicheren Transport des Wasserstoffs ist die Bereitstellung einer Pipeline-Infrastruktur geplant. Die meisten Länder verfolgen hierbei die Strategie der Umwidmung bestehender Erdgastransportleitungen, ergänzt durch Errichtung neuer Pipelines. Die bestehenden Erdgasnetze sind dabei aus unterschiedlichsten Rohrgeometrien und Materialien zusammengesetzt. Bei der Umwidmung von Erdgaspipelines zum Transport von Wasserstoff müssen daher Fragen der Materialverträglichkeit hinsichtlich des als Wasserstoffversprödung bekannten Phänomens der Beeinträchtigung der mechanischen Eigenschaften metallischer Werkstoffe durch Wasserstoff betrachtet werden. Bisherige Forschungsergebnisse und Feldversuche deuten darauf hin, dass die niedriglegierten, ferritischen Stähle, aus denen die Ferngasleitungen des Erdgasnetzes überwiegend bestehen, für den Transport von Wasserstoff unter normalen Betriebsbedingungen geeignet sind. Eine Frage, die bislang weniger Aufmerksamkeit erhielt, ist die, wie sich das Schweißen im Betrieb an Wasserstoffpipelines auf die Materialkompatibilität auswirkt. Im Erdgasnetz sind etablierte Verfahren wie beispielsweise das „Hot-Tapping“ unumgänglich für die Instandhaltung und Erweiterung des Netzes. Hierbei werden an eine im Betrieb befindliche Pipeline geteilte T-Stücke aufgeschweißt, über die die Pipeline dann mit geeigneten Bohrvorrichtungen während eines ununterbrochenen Betriebs angebohrt werden kann. Um zu beurteilen, ob diese Verfahren gefahrlos auf Wasserstoffpipelines übertragen werden können, müssen Problemstellungen betrachtet werden, die sich durch den Wärmeeintrag ins Material beim Schweißen ergeben. Wasserstofflöslichkeit und Diffusionsgeschwindigkeit sind temperaturabhängig. Erhöhte Temperaturen könnten eine Wasserstoffaufnahme ins Material bewirken, die zu einer kritischen Degradation der mechanischen Eigenschaften des Materials führen könnte. Die Temperaturen, die beim Schweißen erreicht werden, führen lokal zur Überschreitung der Austenitisierungstemperatur. Austenit weist eine deutlich höhere Löslichkeit von Wasserstoff auf, während die Diffusionsgeschwindigkeit des Wasserstoffs in dieser Phase deutlich herabgesetzt ist. Es wird vermutet, dass dies zu einer lokal erhöhten Wasserstoffkonzentration führt. Damit geht ein erhöhtes Risiko einer kritischen Materialdegradation einher. Durch die lange Zeitdauer beim Schweißen von mehrlagigen Rundkehlnähten an großen Pipelines, einschließlich einer möglichen Vorwärmprozedur, ist weiterhin zu klären, ob der aus Anwendungsfällen in der Petrochemie bekannte Hochtemperaturwasserstoffangriff auftritt. Der vorliegende Beitrag liefert einen Überblick über das Schweißen im Betrieb an Gaspipelines, hierbei auftretenden Herausforderungen bei der möglichen Anwendung auf Wasserstoffleitungen. Dabei werden auch aktuelle Forschungsprojekte zum Thema Schweißen an Wasserstoffpipelines im Betrieb eingehend diskutiert. In diesem Zusammenhang werden erste Ergebnisse des gemeinschaftlichen Forschungsprojektes „H2-SuD: Einfluss des Schweißens auf die Wasserstoffaufnahme und Degradation im Betrieb befindlicher H2-Ferngasleitungen“ des Deutschen Vereins des Gas- und Wasserfaches (DVGW), der Bundesanstalt für Materialforschung und -prüfung (BAM) und deutscher Gasnetzbetreiber (Open Grid Europe, ONTRAS Gastransport, u.v.m.) präsentiert. T2 - 53. Sondertagung - Schweißen im Anlagen-und Behälterbau 2025 CY - Munich, Germany DA - 18.03.2025 KW - Materialdegradation KW - Pipeline KW - Schweißen KW - Wasserstoff PY - 2025 SN - 978-3-96144-290-4 (Print) SN - 978-3-96144-291-1 (E-Book) VL - 2025 SP - 106 EP - 115 PB - DVS Media GmbH CY - Düsseldorf AN - OPUS4-62911 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kaiser, Sebastian A1 - Erxleben, Kjell A1 - Rhode, Michael A1 - Kannengießer, Thomas T1 - Schweißen im Betrieb an Wasserstoff-Ferngasleitungen N2 - Wasserstoff gilt als Energieträger für die Erreichung der Klimaziele und einer nachhaltigen zukünftigen Energieversorgung. Für den notwendigen Transport des Wasserstoffs in großem Maßstab und über weite Entfernungen ist eine zuverlässige Pipeline-Infrastruktur erforderlich. Umfassende weltweite Forschungsprojekte deuten auf die allgemeine Kompatibilität der verwendeten überwiegend ferritischen Stähle für die vorgesehenen Betriebsbedingungen von bis zu 60 °C bei 100 bar Wasserstoff hin. Dies ist jedoch nicht direkt übertragbar auf schweißtechnische Reparatur- und Wartungsarbeiten an im Betrieb befindlichen Pipelines. Ein im Erdgasnetz etabliertes Verfahren stellt das „Hot-Tapping“ dar, bei dem eine unter Druck stehende Pipeline im Betrieb angebohrt wird. Hierfür kommt ein an die Rohrleitung geschweißtes Formstück zum Einsatz, das die Montage der Bohr-/Lochschneidemaschine ermöglicht. In den Richtlinien EIGA 121/14 bzw. AIGA 033/14 wird darauf hingewiesen, dass das Anbohren von Wasserstoffleitungen kein Routineverfahren darstellt: “[…] a hydrogen hot-tap shall not be considered a routine procedure […]“. Dieser Aussage liegt unter anderem zugrunde, dass das Anschweißen des Formstücks an das Rohr und alle zu erwartenden Wärmebehandlungen vor und nach dem Schweißen eine lokale Temperaturerhöhung verursachen. Insbesondere auch an der Rohrinnenfläche, die dem Wasserstoff ausgesetzt ist. Diese erhöhten Temperaturen begünstigen die Absorption und Diffusion von Wasserstoff in das Material. Besonders zu beachten ist außerdem die lokal auftretende kurzzeitige Austenitisierung des Materials, die eine lokal stark erhöhte Wasserstoffkonzentration verursachen kann. Aus den genannten Gründen gibt diese Studie einen kurzen Überblick über die derzeit weltweit verfügbaren Forschungsprojekte zum Schweißen von Wasserstoff-Pipelines im Betrieb. Vorgestellt werden unter anderem erste Ergebnisse des Kooperationsforschungsprojektes H2SuD, das derzeit an der BAM bearbeitet wird. T2 - 6. Symposium Materialtechnik CY - Clausthal-Zellerfeld, Germany DA - 20.02.2025 KW - Materialdegradation KW - Pipeline KW - Schweißen KW - Wasserstoff PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-632731 SN - 978-3-8440-9961-4 SN - 978-3-8191-0041-3 DO - https://doi.org/10.21268/20250506-12 SN - 2364-0804 SN - 3052-3524 N1 - Serientitel: Fortschrittsberichte der Materialforschung und Werkstofftechnik – Series title: Bulletin of Materials Research and Engineering VL - 15 SP - 381 EP - 390 PB - Shaker Verlag CY - Düren AN - OPUS4-63273 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schröder, Nina A1 - Kromm, Arne A1 - Schröpfer, Dirk A1 - Kannengießer, Thomas T1 - Innovatives Instandsetzungsschweißen von Altstahl: Materialverhalten und Herausforderungen N2 - Aus Gründen der Nachhaltigkeit und Wirtschaftlichkeit gibt es in der stahlverarbeiten-den Industrie einen Trend zum Bauen im Bestand, um kostenintensive Sperrungen oder Rückbau zu vermeiden. Schweißen wird dabei als wirtschaftliches Fügeverfahren im Zusammenhang mit Altstählen kaum genutzt, obwohl Nieten- und Schraubenverbindungen oft unwirtschaftlich sind. Für die Instandsetzung ist häufig beschädigtes Bestands-material durch neue Stähle zu ersetzen bzw. Alt-Neu-Stahl-Mischverbindungen herzu-stellen. Aufgrund der verschiedenen Herstellungsprozesse von Altstählen ist nicht jeder Stahl aus dem 20. Jahrhundert schweißgeeignet. Daher ist zunächst eine Schweißeignungsprüfung erforderlich. In den vorliegenden Untersuchungen wurden verschiedene Altstähle hinsichtlich ihres Schweißverhaltens mittels Dilatometrie analysiert. Ziel war es, eine Datenbasis aus Schweiß-Zustands-Zeit-Diagrammen und Simulationen der Wärmeeinflusszone zu erstellen, um praxisrelevante Schweißuntersuchungen ableiten zu können. Diese geben wesentlichen Aufschluss hinsichtlich ihres schweißmetallurgischen Verhaltens und ihrer Schweißeignung. Solche Grundlagen sind zur Entwicklung innovativer schweißtechnischer Konzepte zur beanspruchungsgerechten Instandsetzung bestehender Altstahl-Infrastruktur in Deutschland notwendig. T2 - 6. Symposium Materialtechnik, 20. bis 21. Februar 2025 CY - Clausthal-Zellerfeld, Germany DA - 20.02.2025 KW - Altstahl KW - Schweiß-ZTU Diagramme KW - Instandsetzungsschweißen KW - Schweißeignungsprüfung KW - Dilatometrie PY - 2025 SN - 978-3-8440-9961-4 DO - https://doi.org/10.21268/20250505-1 VL - 15 SP - 370 EP - 380 PB - Shaker Verlag GmbH CY - Düren AN - OPUS4-63377 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Erxleben, Kjell A1 - Kaiser, Sebastian A1 - Rhode, Michael A1 - Kannengießer, Thomas A1 - Hadick, C. A1 - Schu, K. T1 - Component test concept for evaluation of in-service welding on pressurized hydrogen pipelines N2 - Hydrogen is set as the energy carrier of tomorrow and most countries will achieve large-scale hydrogen transport through the conversion of the natural gas (NG) grid and the construction of new pipelines. The interaction between hydrogen and the pipeline materials differs fundamentally from that of NG, as hydrogen is readily absorbed into the material. Considering the possible hydrogen embrittlement (HE), the compatibility of the pipeline materials (low-alloyed steels with a wide strength/thickness range) must be investigated. However, pipelines require intervention for maintenance, repair, or grid expansion with welding on/onto the pipelines while in service, i.e. the well-known "hot tapping" and "plugging" or “stoppling”. The challenges compared to NG can be broadly divided into the possible austenitization of the inner pipe material exposed to hydrogen and the welding itself. Both result in a significant increase in hydrogen solubility and could potentially pose challenges in terms of HE. Emphasis is placed on the word "could" because knowledge of "hot tapping" on hydrogen pipelines is scarce due a lack of service experience. To this end, this study proposes a concept for a component-like demonstrator with the objectives: (1) safe feasibility of "hot tapping" on pressurized model hydrogen pipeline sections, (2) facilitate ex-post sample extraction for the purpose of quantifying the absorbed hydrogen concentrations, and (3) ensure in-situ temperature measurement during welding to monitor the pipeline surface temperature. For safety reasons in the event of an unintentional "burn-through", a solid cylinder was inserted in the demonstrator to restrict the hydrogen gas volume to a small, pressurized layer. Reference pipeline surface temperature measurements were ensured on comparable, unpressurized geometries. The investigated range of welding conditions was investigated for representative material/thickness combinations (DN50 to DN200), suggesting the feasibility of the demonstrator for the determination of reliable in-service welding conditions for both installed and new pipelines for hydrogen service. T2 - 20th Pipeline Technology Conference ptc2025 CY - Berlin, Germany DA - 06.05.2025 KW - In-service KW - Hydrogen KW - Pipeline KW - Repair welding KW - component test PY - 2025 SP - 1 EP - 11 AN - OPUS4-63168 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -