TY - CONF A1 - Eggert, Lara T1 - Korrosivitätsbestimmungen an Offshoreanlagen N2 - Im Rahmen des Teilprojektes PtX-Wind wurden verschiedene küstennahe sowie offshore Standorte beprobt, um die tatsächliche Korrosivität der Atmosphären zu bestimmen. Mit Offshore Auslagerungsversuchen auf einer Technikplattform (freibewitterter und überdachter Bereich) und an Windenergieanlagen (Außen- und Innenbereich), sollten Daten zur Korrosivität ermittelt werden. Diese stellen eine Grundlage für die dauerhafte und gleichzeitige wirtschaftliche Auslegung des Korrosionsschutzes für Offshore-Prozessanlagen dar. Für Offshore-Windkraftanlagen wird auf Grundlage der abgeschätzten Atmosphäre nach DIN ISO 9223 immer einer Korrosivitätskategorie C5/CX angenommen, was einen entsprechenden Aufwand für den Korrosionsschutz nach sich zieht. Bei den vorliegenden Untersuchungen zeigte sich, dass für Stahl ab einer Höhe von ca. 40 m über der Meeresoberfläche nur eine Korrosivitätskategorie von C3 bis C4 ermittelt wurde. Dies ist vergleichbar mit Standorten an küstennahen Bereichen bzw. Inseln, bei denen die Kategorie C3 vorliegt. Im teilklimatisierten Inneren des Turmes liegt die Korrosivitätskategorie nur bei C2. Die Korrosivitätskategorie C2 wurde aber auch für das nicht klimatisierte Air Transition Deck festgestellt. Auf Grundlage dieser Informationen kann die Auslegung des Korrosionsschutzes sowohl für Außenkomponenten als auch für Anlagenkomponenten in klimatisierten Containern abgeleitet werden. Für alle anderen küstennahen Standorten lag die ermittelte Korrosivität für Zink und Aluminium maximal bei C3. Für Kupfer wurden die höchsten Korrosionsraten mit C4 bis C5 ermittelt, was etwa bei der Auslegung des Korrosionsschutzes elektronischer Bauteile im Außenbereich entsprechend Beachtung finden muss. Neben den Korrosivitätsinformationen liefern die Auslagerungsversuche auch Informationen über die Performance typischer Konstruktionsmaterialien im Offshore Bereich, wie etwa nichtrostender Stähle sowie ausgewählter Korrosionsschutzmaßnahmen. Der Beitrag stellt ausgewählte Ergebnisse der Auslagerungskampagnen vor. T2 - H2Mare-Verbundprojekttreffen PtX-Wind & TransferWind CY - Bremerhaven, Germany DA - 09.07.2025 KW - Atmosphärische Korrosion KW - Standardproben KW - Offshore PY - 2025 AN - OPUS4-63767 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Eggert, Lara T1 - Möglichkeiten im Meerwasserlabor N2 - Das Meerwasserlabor am Eidersperrwerk wurde vorgestellt. Dabei lag der Fokus auf die elektrochemischen Versuchsmöglichkeiten, Monitoring von Versuchsparametern, atmosphärische Korrosion und der Bewuchs an getauchten Prüfkörpern. T2 - H2Mare-Verbundprojekttreffen PtX-Wind & TransferWind CY - Bremerhaven, Germany DA - 09.07.2025 KW - Meerwasserlabor KW - Maritime Korrosion PY - 2025 AN - OPUS4-63766 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ghaznavi, Ali 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 - Acoustic Emission KW - Composite Overwrapped Pressure Vessels, KW - Damage monitoring KW - Machine Learning KW - Deep Learning KW - Deep Neural Network KW - Sequential Neural Network PY - 2025 AN - OPUS4-62915 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Artinov, Antoni T1 - Fracture Mechanics-Based Approach for Fatigue Life Assessment of Welded Structures: The Role of Real Weld Geometries and Welding Residual Stresses N2 - Fatigue failure is a critical concern in offshore wind structures, where welded joints are subjected to cyclic loading over extended service lifetimes. The combined effects of weld geometry [1, 2] and welding residual stresses (WRS) significantly influence the fatigue strength of welds [3-5]. In offshore wind applications, fatigue behavior is further complicated by cyclic loading conditions, where externally applied loads from wind, waves, and ocean currents interact with WRS, causing localized plastic deformation due to high-stress concentrations. Additionally, under prolonged cyclic loading, the redistribution of WRS can result in a shift of the fatigue-prone regions over time, meaning that locations identified as high-risk may not remain the dominant failure sites throughout the structure’s service life [6]. This presents a significant challenge for inspection and maintenance strategies, as conventional monitoring approaches may fail to detect the most vulnerable zones at later stages of operation. Early experimental studies on low-carbon steel plates and butt joints have shown that tensile WRS can reduce fatigue limits by up to 50% compared to stress-relieved specimens [7]. This effect is particularly pronounced in regions with welding defects, such as porosity, lack of fusion, and undercuts, as well as at geometric discontinuities, including weld toes and sharp notches, which induce localized stress gradients. The combined effect of tensile WRS and stress concentrations amplifies the local stress fields, promoting crack initiation and accelerating crack propagation, ultimately reducing the service life of offshore wind structures. Despite the critical role of weld geometry and WRS in fatigue performance, conventional fatigue assessment methods frequently neglect or oversimplify their effects, leading to overly conservative predictions and suboptimal structural designs. Current engineering standards, including BS 7910 (2019), BS 7608 (1993), EN 13001-3-1 (2020), and EN 1993-1-9 (2013), assume high tensile WRS in welded joints and apply simplified fatigue life prediction approaches that eliminate the need for explicit mean stress considerations. While some standards introduce correction factors for different WRS states, these remain highly generalized and lack accuracy. More sophisticated approaches, such as the Integrated Approach to Fatigue Strength Determination of Welded Structures (IBESS) [8], attempt to incorporate WRS into fatigue life assessments but rely on effective load ratios rather than explicitly modeling and considering real WRS distributions in the analysis. Additionally, IBESS does not fully integrate real weld geometries, limiting its predictive accuracy. These limitations result in significant scatter in fatigue life predictions, excessive conservatism, and inefficiencies in structural design. Although existing fatigue models improve on traditional methodologies, to the best of the authors' knowledge a unified framework that fully captures the combined effects of real weld geometries, WRS, and cyclic loading does not exist yet. The present research aims to develop an advanced fracture mechanics-based numerical framework for fatigue life assessment that explicitly accounts for these influencing factors at the specimen level, establishing the foundation for future scaling to component-level applications. T2 - Wind Energy Science Conference CY - Nantes, France DA - 23.06.2025 KW - Fatigue Assessment KW - Wind Offshore Structures KW - Fracture Mechanics KW - Digital Weld Geometries KW - Welding Residual Stresses KW - Numerical Modeling PY - 2025 AN - OPUS4-63591 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kemmler, Samuel T1 - Fully-resolved LBM-DEM simulations of piping erosion during a suction bucket installation N2 - Suction bucket foundations are a cost-efficient and environmentally sustainable solution to install offshore wind turbines, achieved through the application of growing suction pressure inside the bucket until its full embedment into the seabed. A key challenge for the installation process is the occurrence of piping erosion, a phenomenon where fluidization of particles beneath the bucket wall tip causes a drop in suction pressure, potentially leading to installation failure. Despite its significance, the complex physical mechanisms driving piping erosion remain insufficiently understood. To address this knowledge gap, a three-dimensional, fully-resolved coupled LBM-DEM simulation is employed to conduct an in-depth analysis of piping erosion, aiming to identify key influencing parameters, thus enhancing understanding and optimizing the installation process. The simulation of physically relevant problem sizes - comprising hundreds of thousands of grains - is equivalent to computational intensities which demand for extensive computational resources. Results from simulations executed on hundreds of GPUs on the LUMI supercomputer are presented, illustrating the method's capability to tackle this complex challenge. T2 - 10th International Conference on Discrete Element Methods CY - Himeji, Japan DA - 01.07.2025 KW - Offshore wind support structure KW - Suction bucket foundation KW - Piping erosion KW - Micromechanical simulation PY - 2025 AN - OPUS4-63691 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Erxleben, Kjell A1 - Kaiser, Sebastian A1 - Rhode, Michael A1 - Kannengiesser, Thomas A1 - Kromm, Arne T1 - In-service and repair welding of pressurized hydrogen pipelines–a review on current challenges and strategies N2 - Hydrogen is the energy carrier for a sustainable future without fossil fuels. As this requires a reliable transportation infrastructure, the conversion of existing natural gas (NG) grids is an essential part of the worldwide individual national hydrogen strategies, in addition to newly erected pipelines. In view of the known effect of hydrogen embrittlement, the compatibility of the materials already in use (typically low-alloy steels in a wide range of strengths and thicknesses) must be investigated. Initial comprehensive studies on the hydrogen compatibility of pipeline materials indicate that these materials can be used to a certain extent. Nevertheless, the material compatibility for hydrogen service is currently of great importance. However, pipelines require frequent maintenance and repair work. In some cases, it is necessary to carry out welding work on pipelines while they are under pressure, e.g., the well-known tapping of NG grids. This in-service welding brings additional challenges for hydrogen operations in terms of additional hydrogen absorption during welding and material compatibility. The challenge can be roughly divided into two parts: (1) the possible austenitization of the inner piping material exposed to hydrogen, which can lead to additional hydrogen absorption, and (2) the welding itself causes an increased temperature range. Both lead to a significantly increased hydrogen solubility in the respective materials compared to room temperature. In that connection, the knowledge on hot tapping on hydrogen pipelines is rare so far due to the missing service experiences. Fundamental experimental investigations are required to investigate the possible transferability of the state-of-the-art concepts from NG to hydrogen pipeline grids. This is necessary to ensure that no critical material degradation occurs due to the potentially increased hydrogen uptake. For this reason, the paper introduces the state of the art in pipeline hot tapping, encompassing current research projects and their individual solution strategies for the problems that may arise for future hydrogen service. Methods of material testing, their limitations, and possible solutions will be presented and discussed. KW - In-service KW - Welding KW - Hydrogen pipeline KW - Review PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-638847 DO - https://doi.org/10.1007/s40194-025-02127-x SN - 0043-2288 SP - 1 EP - 24 PB - Springer Science and Business Media LLC AN - OPUS4-63884 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Mair, Georg W. A1 - Günzel, Stephan T1 - Der systematische Einsatz der Monte-Carlo-Simulation in der Normung N2 - Im Rahmen der Energiewende erfahren viele Produkte einen umfassenden Markthochlauf. Hierzu müssen neue Technologien entwickelt oder bestehende in kurzer Zeit angepasst werden. Das macht sie besonders anfällig für Zwischenfälle und nachfolgenden Akzeptanzverlust. Zu vermeidende Zwischenfälle hängen oft von den deterministischen Mindestanforderungen in Norm und Recht ab, die erfahrungsbasiert entwickelt wurden. Hier ist die Monte-Carlo-Simulation eine wertvolle Hilfe. Sie erlaubt, auf der Basis von wenigen ermittelten Daten zu bewerten, welche statistische Wirkung aus einer Mindestanforderung resultiert und was angepasst werden muss, um die im Zuge eines Markthochlaufes relevanten Zielgrößen zu erreichen. Ein Verfahren, das im Rahmen der Normung erlaubt, die Wirkung einer Mindestanforderung auf die Ausfallwahrscheinlichkeit zu bewerten, wird zurzeit im Rahmen des Projektes DIN/TS 19472 unter dem NA 016-00-03 AA ausgearbeitet und hier vorgestellt. KW - Wasserstoffspeicher KW - Wirtschaftlichkeit KW - Markthochlauf KW - Zufallsgenerator KW - Normalverteilung KW - Sicherheit PY - 2025 SN - 0722-2912 VL - 2025 IS - 4 SP - 72 EP - 75 CY - Berlin AN - OPUS4-63807 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Mair, Georg W. T1 - DIN TS 19472 - Das Monte-Carlo-Experiment in der Normung N2 - Der Foliensatz erläutert den Denkansatz, die Normstruktur und eine evtl. Programmstruktur für das Normungsprojekt TS 19472. Das Spannungsfeld heutiger Normung basiert auf den immer komplexer vorhersagbaren Eigenschaften Fertigungsstreuung und Bauteilalterung. Während man die Bauteilalterung mit neuen Verfahren der zerstörungsfreien Prüfung usw. betriebsbegleitend bewertet, kann der Fertigungsstreuung mit ihrem Einfluss auf die zu erwartenden Ausfälle nur mit probabilistischen Mitteln direkt begegnet werden. Ein probabilistischer Zulassungsansatz würde aber zu enorm komplexen Bewertungsprozessen führen, die wiederum in ihrer Feldanwendung komplexer zu bewerten und damit ohne langjährige Erfahrung fehleranfälliger als deterministische Verfahren sein dürften. Um diesen Konflikt aufzulösen, bietet es sich zumindest übergangsweise an, den probabilistischen Ansatz nicht unmittelbar in der Zulassung anzuwenden, sondern die in der Breite vertrauten, deterministischen Zulassungsvorschriften auf ihre Wirkung zu überprüfen und ggf. zu optimieren. Hierzu kann die systematisch numerische Wiederholung eines sog. Monte-Carlo-Experiments eingesetzt werden. Hierzu wird für verschiedene Parametersätze, die die Grenze noch akzeptierter Ausfallwahrscheinlichkeit beschreiben, das nachfolgend beschriebene, numerische Experiment wiederholt ausgeführt. Die Wiederholung erfolgt in definierten Variationsschritten über das gesamte Spektrum praktisch relevanter Streuungswerte. Jedes Experiment besteht somit aus der Generierung einer Grundgesamtheit zu dem für den jeweiligen Variationsschritt spezifischen Parametersatz. Danach wird die Grundgesamtheiten in Zufallsstichproben einer definierten Größe aufgeteilt und jede simulierte Stichprobe auf deren Akzeptanz gemäß dem betrachteten Akzeptanzkriterium in der Norm analysiert. Daraus resultiert für jede Grundgesamtheit aus dem Einzelexperiment die Wahrscheinlichkeit zur Annahme einer Stichprobe . Mit der systematischen Wiederholung des Experiments ist der Verlauf  der Akzeptanzwahrscheinlichkeit bekannt, mit der eine grenzwertige Eigenschaft nach einem deterministischen Akzeptanzkriterium noch angenommen werde würde und damit auch ein ungenügendes Baumuster aufgrund der jeweils betrachteten Eigenschaft nicht abgelehnt werden würde. T2 - Sitzung des NA 016-00-03-03 AK „Composite-Flaschen“ des DIN-Normenausschuss Druckgasanlagen (NDG) CY - Berlin, Germany DA - 13.02.2025 KW - Wasserstoffspeicher KW - Probabilistik KW - Markthochlauf KW - Zufallsgenerator KW - Sicherheit PY - 2025 AN - OPUS4-62907 LA - deu 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 - Rolle, Annette 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 - 21stInternational 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 - Raqdioactive KW - Containment PY - 2025 AN - OPUS4-63909 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -