TY - CONF A1 - Auersch, Lutz T1 - Damage detection by flexibility functions and quasi-static moving load tests N2 - The contribution shows measurement examples of cars, floors, foundations, railway tracks, a footbridge, and a railbridge. Vibrations may include modes and waves. Namely in soil-structure interaction, modes are damped, shifted and prevented so that alternatives for the modal analysis are necessary: The approximation of the whole spectrum (flexibility function) and of the whole train passage (moving-load response). T2 - Symposium Emerging Trends in Bridge Damage Detection, Localization and Quantification CY - Luxembourg, Luxembourg DA - 05.05.2023 KW - Flexibility KW - Movin load test KW - Frequency response function KW - Cars KW - Floors KW - Foundations KW - Railway tracks KW - Footbridge KW - Railbridge KW - Damage detection PY - 2023 AN - OPUS4-57951 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz T1 - Train-induced ground vibrations – The emission and transmission from tunnel and surface lines N2 - Train-induced ground vibrations are quite different for tunnel and surface lines. The excitation of the track and ground vibration by the vehicle-track-soil interaction maybe influenced by the stiffer track support of the tunnel invert. The excited waves are propagating on a different path compared to the surface line. The wave propagation in the interior of the soil is calculated by a wavenumber integral in a similar way as the propagation along the surface and a general reduction of < 0.5 has been found. An additional reduction has been found because of the missing Rayleigh wave. The different excitation of tunnel lines is analysed theoretically by the combined finite-element boundary-element method and some results about the influencing tunnel and soil parameters will be shown. Measurements have been made at the Mühlberg-Tunnel in Germany. The vibrations of the train, the track and the soil have been measured simultaneously at the tunnel and a nearby surface line. Spectra will be shown for different train speeds between 60 and 160 km/h. A clear reduction effect for the tunnel line compared to the surface line has been observed in a specific (train-speed-dependent) frequency range. This agrees well with the observations of other research institutes. The mid-frequency tunnel-surface reduction seems to be a consequence of the stiffer track structure which leads to a wider distribution of the axle loads. Therefore, the axle impulses due to the train passage are longer and have a lower frequency content. This will have an effect on the ground vibrations at some distance which are present in case of an irregular transmission path through a ballast and soil with varying stiffness. A similar reduction effect can also be found for other track forms where the axle impulses are distributed on a longer track segment, for example slab tracks, tracks with under ballast plates, under ballast mats or under sleeper pads. T2 - 29th International Congress on Sound and Vibration (ICSV29) CY - Prague, Czech Republic DA - 09.07.2023 KW - Ground vibration KW - Railway tunnel KW - Layered soil KW - Surface-tunnel reduction KW - Measurements PY - 2023 AN - OPUS4-57956 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz T1 - Impacts between different drop masses and different targets in different scales N2 - The Federal Institute of Material Research and Testing has performed many impact tests from very small laboratory tests to very big “free-field” tests with heavy containers on stiff foundations. The first measurements have been done on a big foundation where it should be guaranteed that the foundation is rigid and the container is tested properly. Later on, a smaller drop test facility has been built on the ground inside an existing building. It had to be controlled by prediction and measurements that the drop test will not damage the building. Tests from different heights on soft, medium, and stiff targets have been done to find out rules which allow to identify acceptable and unacceptable drop tests. Later on, the biggest drop test facility has been built for masses up to 200 t. It was necessary for the design of the foundation to estimate the forces which oc-cur during the drop tests. In addititon, the acceptable tests should be selected and controlled by measurements where the impact duration is important. Dif-ferent sensors, accelerometers, accelerometers with mechanical filters, geo-phones (velocity transducers), strain gauges, and pressure cells have been ap-plied for these tasks. Signal transformations and model calculations have been used to check and understand the dynamic measurements. The simplest law is the conservation of the momentum which is a good approximation if the impact is short. If the soil under the foundation has an influence on the deceleration of the container, the maximum foundation velocity is lower than the simple esti-mation. T2 - 10th International Conference on Experimental Vibration Analysis for Civil Engineering Structures CY - Milano, Italy DA - 30.08.2023 KW - Drop test KW - Vibration measurements KW - Container loading KW - Foundation load PY - 2023 AN - OPUS4-58504 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz A1 - Song, Jiaojiao T1 - Analysis of intact and damaged (floating) slab tracks by finite-element boundary-element models and by measurements N2 - The damage detection and repair control have become important tasks for slab tracks. Different intact and damaged slab tracks have been investigated theoretically and experimentally for train passages and hammer impacts. The following damages have been considered: The loss of contact between the sleeper and the track slab, between the track slab and the base slab, and between the base slab and the base layer. At first, a slab track with a gap between the track slab and the base layer has been calculated by the combined finite-element boundary-element method which correctly incorporates the behaviour of the infinite soil. The basic results are the track displacements of the rail, the track slab, and the base layer along the track which are caused by a single axle load. These solutions are properly superposed for to get the complete train load. The influence of track and soil parameters and of the track damage has been analysed. For the intact track, the compliance of the soil is dominant whereas the track bending stiffness becomes more important for the damaged track. By comparing the calculated results with the measurements, the length of the gap could be quantified. A slab track with a loose sleeper (without contact to the supporting track slab) was analysed by the transfer function between the displacements and the hammer force (receptance functions) where a resonance appeared in case of the damage. Differences between the different track elements confirmed the detection of the damage. A floating slab track with a thin rubber layer has been investigated for a possible gap between the base slab and the base layer. The behaviour of the intact track has been calculated by a wavenumber-domain method, and the same behaviour has been found in the measurements at several track sections, indicating that there is no damage. Finally, a floating slab track with steel springs and viscous fluid dampers has been measured in the Tongji laboratory. The modes of the floating track slab and the transfer function with corresponding resonances have been calculated and successfully compared with results from wheelset drop tests. T2 - 3rd International Conference of Rail Transportation CY - Shanghai, China DA - 07.08.2024 KW - Slab tracks KW - Damage KW - Vibration measurements KW - Finite-element boundary-element method PY - 2024 AN - OPUS4-61227 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Baeßler, Matthias T1 - Maßgeblicher Einfluss geotechnischer Interaktionsprobleme auf den Tragwerksentwurf: Zwei spezielle Fallbeispiele N2 - Geotechnische Interaktionsprobleme können den Entwurf eines Tragwerks maßgeblich beeinflussen. Anhand zweier Fallbeispiele - dem Schotteroberbau auf Brücken im HGV und der Installation großer Monopiles - werden aktuelle Fälle aus dem Forschungsrepertoire der BAM vorgestellt. T2 - Geotechnische Seminarreihe am IBF des KIT CY - Karlsruhe, Germany DA - 23.01.2025 KW - Schotter auf Brücken im Hochgeschwindigkeitsverkehr KW - Pfahlfussbeulen KW - Beschleunigungsgrenzwert KW - Rammung KW - Monopiles PY - 2025 AN - OPUS4-62451 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Baeßler, Matthias T1 - OWEC repowering from a structural engineering and research perspective N2 - A significant number of new wind farms has to be installed and, at the same time, existing wind farms reaching the end of their planned life need to be reused efficiently to ensure that the ambitous goals for deploying offshore wind are met. Some relevant reuse alternatives for offshore wind farms are lifetime extension, repowering utilizing existing substructures and full replacement. In this presentation - starting from experience gained from extending the lifetime of the of the U1 metro viaduct in Berlin - we discuss end-of-life decision making in offshore wind. We focus particularly on issues concerning substructures and highlight existing challenges and opprtunities in research and development. T2 - RWE RePowering Event CY - Wilhelmshaven, Germany DA - 10.10.2023 KW - Offshore wind KW - End-of-life decision making KW - Repowering KW - Substructures PY - 2023 AN - OPUS4-58632 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Baeßler, Matthias T1 - Recap: Main Results of the BUMP Study and Relevance for VERBATIM N2 - Zusammenfassung des Forschungsprojekts BUMP hinsichtlich der Relevanz für das Projekt VERBATIM N2 - BUMP had been a theoretical prestudy on open issues for the pile tip buckling of large monopiles. The presentation summarizes the main results and considers the impact for the ongoing VERBATIM project. VERBATIM is set up as a mainly experimental verification project for pile buckling. T2 - Kick-Off Projekt VERBATIM CY - BAM, Berlin, Germany DA - 23.01.2020 KW - Buckling piles circular shells PY - 2020 AN - OPUS4-50515 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Baeßler, Matthias T1 - Dynamisches Verhalten und Überwachung des Großen Fallturms der BAM in Horstwalde N2 - Falltürme sind Bauwerke, die als Versuchsanlagen sehr speziellen, impulsartigen Belastungen ausgesetzt sind. Am Fallturm auf dem Testgelände Technische Sicherheit (TTS) der BAM wurde bei Routineinspektionen eine Abnahme der strukturellen Integrität in Form von Vorspannungsverlusten in den Bolzen der Stahlverbindungen festgestellt. Um ein Verständnis für die zugrundeliegenden Trag- und Schädigungsmechanismen zu erlangen, wurde ein umfassendes Structural Health Monitoring (SHM) System geplant und am Bauwerk installiert unter Nutzung von digitalen Bauwerksmodellen. Für die Auslegung des Überwachungssystems, insbesondere aber zur Unterstützung der Untersuchung des Schädigungsprozesses, wurden Finite-Elemente-Modelle erstellt. Um sicherzustellen, dass die FE-Modelle das reale Tragwerksverhalten mit ausreichender Genauigkeit abbilden, mussten sie jedoch in Bezug auf die gemessenen Antworten des Tragwerks kalibriert werden. Der vorliegende Beitrag beschreibt experimentelle und numerische Untersuchungen zur Identifizierung des strukturellen Systems des Stahlrohrgitterturms in Vorbereitung einer Überwachungskampagne. Die Auswertung von gemessenen Schwingungen unter ambienter Anregung ermöglichte die Identifizierung der Eigenfrequenzen mehrerer globaler Schwingungsmoden des Fallturms. Zur Modellvalidierung wurde zunächst eine Sensitivitätsanalyse durchgeführt, um die Parameter mit dem größten Einfluss zu ermitteln. Anschließend wurde ein evolutionärer Algorithmus (EA) zur Optimierung nach dem Prinzip der Minimierung der Differenzen zwischen gemessenen und simulierten charakteristischen Antworten eingesetzt. Das aktualisierte Modell wurde schließlich an der dynamischen Reaktion der Turmstruktur infolge einer realen Falltest-induzierten Stoßbelastung validiert. Die Ergebnisse zeigten eine gute Übereinstimmung zwischen numerischen und experimentellen Ergebnissen. N2 - Drop test towers are structures subjected to very specific dynamic loadings. At the drop test tower at the Test Site Technical Safety (TTS) of BAM routine inspections revealed a decline of structural integrity in form of loss of pretension in bolts of structural steel connections. To get an understanding about the underlying damage mechanisms as well as to assure the structural safety in operation, a multifaceted Structural Health Monitoring (SHM) system was planned and installed at the structure with the help of digital models. For planning the monitoring system but especially for supporting the investigation of the damaging process finite element models are deployed. Though, to ensure the capability of the FE model to reproduce the real structural behavior in sufficient accuracy, it needs to be calibrated in respect to measured responses of the structure. The present contribution describes experimental and numerical investigations to identify the structural system of the steel tube lattice tower in preparation of the monitoring campaign. An ambient vibration test allowed the identification of the natural frequencies of several global vibrational modes of the drop test tower. For model updating first a sensitivity analysis is applied to identify the most influencing parameter. In succession a genetic algorithm was applied for optimization in the sense of minimization of the difference between measured and simulated characteristic responses. The updated model is finally validated on the dynamic response of the tower structure to a real drop test induced impact loading. The results showed a good agreement between numerical and experimental results though the robustness of the simulation should be improved by more sophisticated numerical modelling. T2 - 7. VDI-Fachtagung Baudynamik CY - Würzburg, Germany DA - 27.04.2022 KW - Großer Fallturm Horstwalde KW - Structural Health Monitoring KW - Belastungsversuch KW - Modalanalyse KW - Schwingungsdynamik KW - Finite Elemente Simulation PY - 2022 AN - OPUS4-55470 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Baeßler, Matthias T1 - Anwendungsszenarien und Referenzanwendungen sensorbasiertes Monitoring N2 - Präsentiert wird eine Kategorisierung von Anwendungsszenarien für sensorbasiertes Monitoring und die Planung für die Referenzbauwerke mit SHM-Anwendungen. Im Rahmen des Forschungsvorhabens Aistec Pro werden Anwendungsszenarien für sensorbasiertes Monitoring kategorisiert und in Referenzanwendungen umgesetzt. Der Vortrag gibt einen Überblick über die abgeschlossene Planung. T2 - Jahrestreffen Verbund Aistec-Pro CY - Bonn, Germany DA - 17.09.2025 KW - SHM KW - Monitoring KW - Brückensicherheit KW - Aistec Pro PY - 2025 AN - OPUS4-64124 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Baeßler, Matthias T1 - Numerical Modelling of Local Pile Deformations and Buckling incorporating the Pile-Soil-Interaction N2 - Pile Tip Buckling and Buckling of embedded piles both depend very much on the pile-soil-interaction and its modelling. The presentation gives an overview about current problems and research activities in the light of the development of numerical models. T2 - WESC Wind Energy Science Conference CY - Hannover, Germany DA - 25.05.2021 KW - Offshore Wind Energy Converter KW - Pile Foundation KW - Monopile Buckling KW - Pile Tip Buckling PY - 2021 AN - OPUS4-53033 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Baeßler, Matthias T1 - Introduction to the Workshop Life Time Extension N2 - The article introduces the topic of life time extension for offshore wind turbines. On the one hand, analogies are drawn with the topic of old steel bridges. On the other hand, potential regulatory issues and minimum requirements are discussed. T2 - Workshop Offshore Wind CY - Berlin, Germany DA - 26.02.2025 KW - Life Time Extension KW - Offshore Wind PY - 2025 AN - OPUS4-62640 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Baeßler, Matthias T1 - Large Monopiles: Experimental and numerical investigation of monopile tip buckling during installation as well as of local pile buckling under operational conditions N2 - The research project Verification of Buckling Assessment and Behaviour in Large Monopiles (VERBATIM) focuses on challenges arising due to the ongoing increase of dimensions of monopiles as foundation for offshore wind turbines. This project is focused on two main topics: - Monopile tip buckling during pile installation - Local buckling of embedded piles during operation It is known from previous investigations and experiences in practice that large deformations of a monopile tip during offshore installation works can occur. These large deformations initiated at the tip of the monopile are commonly referred to as “pile tip buckling”. Own research focuses on optimising monopile dimensions to reduce the cost of monopile foundations for offshore wind turbines while preventing pile tip buckling. Buckling of embedded cylindrical shells for offshore structures is a common engineering task. Structures can be analysed using standard software and have been done so in recent studies e.g., Gottschalk. However, the trend towards larger monopile and optimised structures has led to a fundamental need for better and verified models. A main challenge is the submodelling of the structure-soil-interaction. Developing such complex models is one main goal of the VERBATIM project. For both main topics model tests were performed at the laboratories of BAM and TU Berlin. These experimental results were used to verify related numerical models and simulations. T2 - WindEurope CY - Copenhagen, Denmark DA - 25.04.2023 KW - Monopiles KW - Tip Buckling KW - Pile Buckling KW - Foundations KW - Offshore KW - Windenergy PY - 2023 AN - OPUS4-57405 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Baeßler, Matthias T1 - On the Reassessment of Bridge Superstructure Vibrations for High-Speed Traffic N2 - The acceleration thresholds of bridge superstructures remain criti-cal for designing and reassessing railway bridges on high-speed lines, with ballasted track systems historically limited to 3.5 m/s² vertical accelerations due to destabilization risks. As part of the European InBridge4EU project, this study addresses methodological uncertainties in linking vertical bridge vibrations to lateral track creep—a key focus area for modernizing assess-ment protocols. A comparative analysis of two acceleration postprocessing methods (peak identification vs. fatigue-derived rainflow counting) as part of a recently proposed framework was conducted using an example bridge and train combination. Results demonstrate that rainflow counting yields more conservative creep estimates with the bulk of cumulative vibration-induced creep attributable to accelerations exceeding 3 m/s². However, discretizing acceleration ranges into 1 m/s² bins introduced significant errors compared to continuous cycle data, highlighting sensitivity to analysis parameters. These findings underscore the complexity of reconciling laboratory-derived harmonic vibration models with real-world bridge dynamics, where non-uni-form acceleration patterns dominate. The research directly informs ongoing efforts to refine standardized criteria for ballasted track stability, particularly through the InBridge4EU project's systematic re-evaluation of vibration lim-its and their engineering implications. By quantifying discrepancies between computational approaches, this work advances the development of robust protocols for predicting track degradation under high-speed operational loads. T2 - 11th International Conference on Experimental Vibration Analysis for Civil Enginering Structures (EVACES 2025) CY - Porto, Portugal DA - 02.07.2025 KW - Infrastructure KW - Railway bridges KW - Ballasted track KW - Railway bridge dynamics KW - Rainflow counting PY - 2025 AN - OPUS4-63658 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Baeßler, Matthias T1 - Review of Ballasted Track Destabilization on Shake Table Tests N2 - Shake table tests have been used for a long time to understand the densification and fluidization of granular materials. While purely vertical shaking is quite unlikely to be found in vibration analysis when it comes to granular materials as soils, it has been found that the vertical vibration of railway bridge support structures can affect the fabric of the ballasted track on top. Starting from the experience at French railway lines with destabilizing track conditions on short bridges in high speed lines in the 1990s, various shake table test configurations have been used to investigate the destabiliza-tion of ballast at high acceleration levels. This article describes the effects of the variously investigated dynamic excitations of railway bridges on the bal-lasted track itself. T2 - 11th International Conference on Experimental Vibration Analysis for Civil Enginering Structures (EVACES 2025) CY - Porto, Portugal DA - 02.07.2025 KW - Railway bridge dynamics KW - Acceleration limit KW - Ballast destabilization KW - Shake table tests PY - 2025 AN - OPUS4-63659 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Baeßler, Matthias T1 - On potentials and challenges of physics-informed SHM for civil engineering structures N2 - Physics-informed structural health monitoring, which incorporates realistic physical models of material behavior, structural response, damage mechanisms, and aging processes, offers a promising framework to enhance monitoring capabilities and inform operation and maintenance planning. Nevertheless, the technical challenges and model requirements associated with this approach are highly context-dependent and can vary significantly across different applications. The presentation focusses on two case studies that highlight challenges and progress in Physics informed SHM. T2 - SHMII-13 CY - Graz, Austria DA - 01.09.2025 KW - SHM KW - Physics informed KW - Hydrogen Stress Corrosion Cracking PY - 2025 AN - OPUS4-64326 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Baeßler, Matthias A1 - Aubram, Daniel T1 - Vorstellung OWA VERBATIM N2 - Das Risiko von Pfahlfussbeulen ist ein wesentlicher Grund für hohe Pfahlwandstärken bei Monopiles. Das Projekt VERBATIM - Verifikation des Beulnachweises und –verhaltens großer Monopiles zielte darauf ab, Beulphänomene zu untersuchen, die sich sowohl auf die plastischen Verformungen der Pfahlspitze während der Installation als auch auf das Beulen des eingebetteten Pfahls in der Nähe des Seebodens beziehen. Auf der Basis aufwändiger Versuche wurden numerische Modelle entwickelt und validiert. Dies ermöglicht ein besseres Verständnis des Beulverhaltens, um die Wanddicke zu reduzieren, was Kosteneinsparungen bei der Stahlmenge sowie die Entwicklung sicherer und optimierter Strukturen erlaubt. Die bisherigen Designverfahren konnten die erfolgreiche Installation der Monopiles gewährleisten. Da die Größe von Monopiles jedoch stetig zunimmt, wird die Entwicklung verbesserter Designverfahren für sichere und kostengünstige Fundamente immer wichtiger. Der Rückenwind-Vortrag gibt eine Übersicht zu den durchgeführten Untersuchungen und Ergebnissen T2 - Rückenwind Aktuelles aus der Windenergieforschung (PTJ) CY - Online meeting DA - 21.06.2024 KW - Offshore Windenergy Pile Buckling PY - 2024 AN - OPUS4-60349 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Baeßler, Matthias A1 - Balscheit, Hagen A1 - Schepers, Winfried A1 - Victor, Albrecht A1 - Daryaei, Reza A1 - Bianco, Marcelo A1 - Starost, Christina T1 - Close-out Webinar OWA VERBATIM N2 - The risk of pile base buckling is a major reason for high pile wall thicknesses in monopiles. The VERBATIM project - Verification of the buckling detection and behaviour of large monopiles - aimed to investigate buckling phenomena related to both the plastic deformation of the pile tip during installation and the buckling of the embedded pile near the seabed. Numerical models were developed and validated on the basis of extensive tests. This enables a better understanding of the buckling behaviour in order to reduce the wall thickness, which allows cost savings in the amount of steel and the development of safer and optimised structures. The previous design procedures were able to ensure the successful installation of the monopiles. However, as the size of monopiles continues to increase, the development of improved design methods for safe and cost-effective foundations is becoming increasingly important. The presentation provides an overview of the investigations carried out and the results. T2 - Webinar Carbon Trust Offshore Wind Accelerator CY - Online meeting DA - 22.05.2024 KW - Offshore Windenergy Pile Buckling PY - 2024 AN - OPUS4-60348 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Baeßler, Matthias A1 - Cuéllar, Pablo A1 - Schepers, Winfried T1 - VERBATIM: Project Introduction and Large Scale Experiments N2 - The presentation summarizes the scope of the joint project VERBATIM on buckling of large Monopiles. The presented work from the authors focusses on the experimental field tests of large predented piles during driving and a numerical investigation on the observed buckling behaviour. T2 - Colloquium „Buckling of Offshore Wind Energy Structures“ CY - Berlin, Germany DA - 14.02.2024 KW - Buckling KW - Offshore KW - Wind Energy Structures KW - Monopiles KW - Pile-Tip-Buckling PY - 2024 AN - OPUS4-59535 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Baeßler, Matthias A1 - Eichner, Lukas A1 - Weise, Sigurd T1 - Digital building management for OWEC-structures N2 - The presentation summarizes the data management and Digital modeling processes in the recurring inspection of wind turbines as developed in DiMoWind-Inspect. T2 - Windforce 2024 CY - Bremerhaven, Germany DA - 10.06.2024 KW - DiMoWind RDS-PP Maintenance Digital Twin Offshore Wind Energy PY - 2024 AN - OPUS4-60351 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Baeßler, Matthias A1 - Haake, Gerrit T1 - ReNEW - Entscheidungstools für die Nutzungsverlängerung und das Repowering von Windenergieanlagen N2 - Der Vortrag gibt einen Überblick über gängige Nachnutzungskonzepte, die im Rahmen des Forschungsvorhabens ReNEW untersucht werden. Hierzu wir eine probabilistisches Entscheidungsmodell eingeführt. Die Möglichkeiten von Bauwerksertüchtigungen werden erörtert. T2 - RAVE ROWD Workshop 2024 CY - Hannover, Germany DA - 10.12.2024 KW - Windenergieanlagen KW - Bauwerksertüchtigung KW - Offshore-Windparks KW - Repowering PY - 2024 AN - OPUS4-62237 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Baeßler, Matthias A1 - Kannengießer, Thomas T1 - Aktivitäten in Forschung und Zulassung im Bereich Windenergie N2 - Die vielfältigen Tätigkeiten der BAM im Bereich technischer Sicherheit von Windenergieanlagen werden vorgestellt und im Bereich aktueller Entwicklungen in der Fügetechnik detailliert. T2 - Arbeitskreis Gründungsstrukturen und Stahlbau der WAB CY - Online meeting DA - 13.04.2021 KW - BAM Windenergie Fügetechnik PY - 2021 AN - OPUS4-53026 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Baeßler, Matthias A1 - Weise, Sigurd T1 - Digitalization of Maintenance Processes N2 - Main aspects of Digitalization of Maintenance Processes are summarized and discussed. Introduction to the Windforce2024 session organised by BAM. T2 - Windforce 2024 CY - Bremerhaven, Germany DA - 11.06.2024 KW - Maintenance Digital Twin Offshore Wind Energy PY - 2024 AN - OPUS4-60350 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Baier, Johanna T1 - Structural design of rammed earth considering the impact of moisture N2 - In March 2024, a research project was initiated at BAM with the aim of developing a design concept for rammed earth construction. It is based on experimental and numerical investigations into the mechanical load-bearing behaviour at both material and component level. As the mechanical parameters of earth building materials are strongly dependent on material moisture, the moisture behaviour of rammed earth is also being investigated in more detail. T2 - LEHM 2024 - 9. Internationale Fachtagung für Lehmbau CY - Weimar, Germany DA - 27.09.2024 KW - Rammed earth KW - Structral design KW - Material moisture PY - 2024 AN - OPUS4-62031 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Baier, Johanna T1 - Zukunft bauen mit Lehmmauerwerk N2 - Vortrag über Lehmmauerwerk an der BBIK. Inhalte: Historie des Lehmbaus, Grundlagen zum Baustoff Lehm, Bemessung von Lehmmauerwerk und Gegenüberstellung mit anderen Massivbauweisen. T2 - Tragwerksplanertag der Brandenburgischen Ingenieurkammer CY - Potsdam, Germany DA - 20.11.2025 KW - Lehm KW - Lehmmauerwerk PY - 2025 AN - OPUS4-65092 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Baier, Johanna T1 - Down to Earth - Stampflehm N2 - Der Vortrag „Stampflehm“ gibt einen kurzen Überblick zur stofflichen Zusammensetzung von Stampflehm sowie zu verschiedenen Fertigungstechniken im Stampflehmbau. Es werden wichtige konstruktive Details erläutert und Hinweise bezüglich der Ausführung von Stampflehmwänden gegeben. Darüber hinaus wird das aktuell gültige Bemessungskonzept vorgestellt und dessen Schwachstellen aufgezeigt. Im Anschluss erfolgt eine Gegenüberstellung von Stampflehm mit verschiedenen Massivbauweisen hinsichtlich Tragfähigkeit, Schall- und Brandschutz sowie der Ökobilanz. Abschließend wird von aktuell laufenden Forschungsvorhaben im Bereich des Stampflehmbaus berichtet. T2 - Down to Earth - digitale Ringvorlesung CY - Online meeting DA - 10.12.2025 KW - Stampflehm PY - 2025 AN - OPUS4-65093 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Baier, Johanna A1 - Ziegert, Christof T1 - DIN 18940 für tragendes Lehmsteinmauerwerk – Potenzial und erste Anwendungserfahrungen N2 - Mit der Veröffentlichung der DIN 18940 Juni 2023 steht in Deutschland eine zeitgemäße Bemessungsgrundlage für tragendes Lehmmauerwerk zur Verfügung, die derzeit europaweit einmalig ist. Während nach bisherigen Vorschriften lediglich zweigeschossige Gebäude mit tragendem Lehmsteinmauerwerk realisierbar waren, ermöglicht die DIN 18940 nun den Einsatz von Lehmsteinmauerwerk in fünfgeschossigen, bis zu 13 m hohen Gebäuden. Das Bemessungskonzept der DIN 18940 lehnt sich an die Grundprinzipien der vereinfachten Berechnungsmethoden für unbewehrte Mauerwerksbauten nach DIN EN 1996-3/NA an und berücksichtigt dabei die materialspezifischen Eigenschaften von Lehmsteinmauerwerk. Anpassungen waren aufgrund der feuchteabhängigen Festigkeits- und Verformungskenngrößen sowie der im Vergleich zu herkömmlichem Mauerwerk geringen Steifigkeit erforderlich. Ein Vergleich mit konventionellem Mauerwerk aus Ziegeln, Porenbeton und Kalksandsteinen zeigt, dass Lehm hinsichtlich Tragfähigkeit und bauphysikalischen Eigenschaften im Bereich der Gebäudeklasse 1-4 konkurrenzfähig ist. Besonders die geringen CO2-Emissionen und die vollständige Rezyklierbarkeit machen Lehmsteinmauerwerk zu einer klimagerechten Alternative. Weiterhin werden erste Projekte vorgestellt, die nach DIN 18940 geplant wurden. Aus den Anwendungserfahrungen werden materialgerechte Entwurfsgrundsätze für Gebäude aus Lehmsteinmauerwerk formuliert. Abschließend zeigen Einblicke in laufende Forschung und zukünftige Entwicklung, wie das Potenzial von Lehmsteinmauerwerk weiter gesteigert werden kann. T2 - LEHM 2024 - 9. Internationale Fachtagung für Lehmbau CY - Weimar, Germany DA - 27.09.2024 KW - Lehmmauerwerk KW - Ökobilanzierung KW - Normung PY - 2024 SP - 1 AN - OPUS4-62034 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Balscheit, Hagen T1 - Buckling Behavior of embedded Shells N2 - Presentation on ongoing test campaign on buckling of embedded piles, which is part of the VERBATIM-Project. T2 - Phd Seminar LFU-Innsbruck CY - Innsbruck, Austria DA - 24.06.2022 KW - Buckling KW - Monopiles KW - Windenergy KW - Foundations KW - Offshore PY - 2022 AN - OPUS4-55458 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Balscheit, Hagen T1 - Nichtlineares Tragverhalten stahlbaulicher Offshore-Strukturen unter spezieller Berücksichtigung der Bauwerk-Boden-Interaktion N2 - Der Vortrag gibt einen Überblick über die ingenieurmäßige Handhabung der stahlbaulichen Bemessung von großen Monopiles für Offshorewindenergieanlagen. Besonderer Focus liegt dabei auf jenen Phänomenen, welche durch eine starke Interaktion zwischen Stahlstruktur und Boden gekennzeichnet werden. T2 - Ringvorlesung: Praxisreihe Stahlbau CY - Innsbruck, Austria DA - 09.05.2023 KW - Pile Tip Buckling KW - Shell Buckling KW - Soil Struture Interaction PY - 2023 AN - OPUS4-57521 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Balscheit, Hagen T1 - Offshore Gründungen - Nichtlineare Effekte bei der stahlbaulichen Auslegung großer Pfahlgründungen für Offshore Windenergieanlagen N2 - Dieser Kurzvortragg erläutert nichtlineare Phänomene die angesichts der aktuell wachsenden Dimensionen von Monopfahlgründungen für Offshorewindenergieanlagen zunehmend an Bedeutung gewinnen. Insbesondere wird dabei auf das Pfahlfußbeulen sowie das Schalenbeulen des bereits installierten Pfahles eingegangen. T2 - 27. Brandburgischer Bauingeniertag BBIT2023 CY - Cottbus, Germany DA - 09.06.2023 KW - Beulen KW - Pfahlfußbeulen KW - Stabilität KW - Monopile KW - Windenergie PY - 2023 AN - OPUS4-57653 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Balscheit, Hagen T1 - Soil Embedded Piles - Reference Tests for Model Validation N2 - This presentation shows buckling tests on embedded piles conducted within the VERBATIM project. The generated data may serve as a valuable validation basis for numerical buckling design verification of Windenergy foundations in terms of the GMNIA concept. T2 - Buckling of Offshore Wind Energy Structures : 2-Day Buckling Colloquium CY - Berlin, Germany DA - 14.02.2024 KW - Wind Energy KW - Shell Buckling KW - Offshore Structures KW - GMNIA PY - 2024 AN - OPUS4-59536 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Balscheit, Hagen T1 - Buckling Design of Soil Embedded Piles N2 - Monopiles sind die gängigste Gründungskonstruktion für Offshore-Windkraftanlagen, doch größere Turbinen erfordern Pfahldurchmesser über 10 m und Pfahllängen über 60 m, was das Risiko von lokalem Beulen in den eingebetteten Bereichen erhöht. Aktuelle Richtlinien berücksichtigen die Pfahl-Boden-Interaktion nicht ausreichend so dass nur ein vollständig numerischer GMNIA-Nachweis geführt werden kann. Für derartige Berechnungsmodelle fehlen allerdings derzeit noch validierungswerte für eingebettete Schalen. Experimente im Rahmen des VERBATIM-Projekts schließen diese Lücke. T2 - Phd Conference Univiersity Innsbruck CY - Innsbruck, Austria DA - 05.02.2025 KW - Buckling KW - Wind Energy KW - Monopile Foundation PY - 2025 AN - OPUS4-62534 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Balscheit, Hagen T1 - Evaluation of pile tip buckling based on large scale tests N2 - Der Vortrag zum zugehörigen Konferenzbeitrag beschreibt eine groß angelegte Feldtestkampagne mit 16 Rammversuchen, um das Risiko des plastischen Versagens der Pfahlspitzen besser zu verstehen 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 (ISFOG) 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 AN - OPUS4-63391 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Balscheit, Hagen T1 - Experimental Investigation on Buckling Behavior of soil-embedded Piles N2 - Monopile-Gründungen sind die mit Abstand am häufigsten verwendete Gründungskonstruktion für Offshore-Windenergieanlagen. Ein wesentliches Problem bei der Bemessung ist das lokale Beulen des Gründungspfahls, welches typischerweise im Bereich der Bettung auftritt. Aufgrund der Nichtlinearität der Bettungsrandbedingung sind klassische Bemessungsansätze nicht anwendbar, so dass der Bemessungsingenieur auf eine vollständig numerische Berechnung zurückgreifen muss. In diesem Vortrag wird eine experimentelle Versuchskampagne zur Erzeugung von Kalibrierungsdaten für solche numerischen Modelle vorgestellt. Eine ausführlichere Darstellung findet sich im gleichnamigen Artikel. T2 - EUROSTEEL 2023 CY - Amsterdam, Netherlands DA - 11.09.2023 KW - Wind KW - Wind Energy KW - Offshore KW - Shell Buckling KW - Soil-Structure-Interaction PY - 2023 AN - OPUS4-58365 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Costard, Rene A1 - Hering, Marcus T1 - Explosionsauswirkungen auf Strukturen N2 - Wir berichten über die Entwicklungen des AP2 im Hinblick auf Explosionsauswirkungen auf Strukturen und den Weg zur systematischen messtechnischen Erfassung zur ganzheitlichen Bewertung der Bauwerksicherheit unter Detonationsbelastung. Zusätzlich werden die Vorführungen zu Kontaktdetonationen während der 16. Informationsveanstaltung Sprengstoffe und Pyrotechnik vorgeführt. T2 - 16. Informationsveranstaltung Sprengstoffe und Pyrotechnik CY - Berlin, Germany DA - 20.05.2025 KW - Explosion KW - Kontaktdetonation KW - Blast PY - 2025 AN - OPUS4-63192 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Costard, René T1 - Auswirkungsbetrachtungen auf Strukturen T1 - Scaling of Blast Effects on Reinforced Concrete Structures N2 - Protection against terroristic or accidental scenarios in industrial settings requires suitable designs of structures to resist blast loads. Field testing as well as finite element simulations are among the techniques available to engineers in the understanding of the structural behavior against blast loading. As blast testing of complex scenarios can be very resource intensive, tests are generally performed for simplified scenarios. Numerical tools can be used to model these scenarios to get better insight into blast loading, structural response, and the resulting damage to the structure. During the next steps, the simplified scenario is successively modified in numerical simulations to incorporate complexities that cannot be covered in blast testing experiments. One of the conditions for this approach to work is that the original simplified numerical simulation is valid. The scopes and challenges encountered in such a validation are the focus of this presentation/article. A relatively ‘simple’ field test of a horizontal reinforced concrete (RC) slab subjected to blast loading is taken as an example for validation of the performance of numerical tools. The blast test incorporated various measurement techniques to quantify the blast load as well as the behavior of the RC slab. Blast load was measured using flush mounted piezoelectric pressure gauges, whereas acceleration sensors and fiber-optic sensor cables were used to characterize the dynamic behavior of the slab under blast loading. Additionally, damage characteristics were ascertained also using fiber optic sensing. The application of such measurement techniques, along with different numerical software available for the analysis of the scenario in question, demonstrate the scope of our contribution. When it comes to the challenges, it begins with proper instrumentation of the test specimen followed by the data processing. For numerical modelling, geometric conditions with appropriate boundary constraints, physical conditions such as the configuration of the rebars, as well as material parameters add to this challenge. The issues of choosing appropriate material models and comparison of results with multiple software tools will be discussed. This discussion forms the basis for a coherent approach to technical-safety assessment of blast effects on structures in its broader sense. T2 - Beiratssitzung Infrastruktur CY - Berlin, Germany DA - 11.04.2024 KW - Blast KW - Scaling KW - Fiber optic sensing KW - CFD KW - FEM PY - 2024 AN - OPUS4-59849 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Costard, René T1 - Explosionsauswirkungen auf Strukturen Versuche und Simulationen N2 - Vorstellung der Versuche von Explosionsversuchen auf dem TTS. Diese werden ergänzt durch die Ergebnisse durchgeführter Simulationen und zeigen die Wirkung von zivilen Explosivstoffen auf Gebäudestrukturen und die aufgetretenen Schädigungen. T2 - 46. Informationstagung Sprengtechnik CY - Siegen, Germany DA - 25.04.2025 KW - Explosivstoff KW - Skalierung KW - Strukturauswirkung KW - Numerische Simulation PY - 2025 AN - OPUS4-62998 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Cuéllar, Pablo T1 - Geotechnical challenges in the field of Offshore Wind Energy. Micromechanical perspectives beyond the FEM N2 - This talk provides a brief overview on some geomechanical phenomena and problematic issues in the field of offshore wind-energy geotechnics, with reference to their associated challenges for a numerical analysis/simulation. These may include large deformations, fluid coupling and grain-scale phenomena, all of which are generally difficult to be addressed with conventional FE techniques. These challenges are illustrated here with a practical example for the retrofit of axially loaded piles using compaction grouting techniques. In this case, the mechanical effects of the retrofit may be analysed with standard FE techniques, but require the adoption of strong assumptions, while the injection process itself can only be analysed with special techniques such as the MPM. Finally, an LBM-DEM framework for the micromechanical analysis of such problems is introduced and a practical application for the estimation of the soil resistance to driving (SRD) in layered profiles is discussed. T2 - Online Symposium on Meshfree models for Engineers: Where are they really worthwhile? CY - Online meeting DA - 01.12.2022 KW - Offshore wind energy KW - Offshore geotechnics KW - Micromechanical simulation KW - LBM-DEM KW - Pile retrofit system PY - 2022 AN - OPUS4-56450 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Cuéllar, Pablo T1 - Deep foundations for offshore wind turbines. Part 2: Lateral behaviour and Advanced topics T1 - Cimentaciones profundas para aerogeneradores marinos. Parte 2: Comportamiento lateral y temas avanzados N2 - his presentation deals with the phenomenology and design of pile foundations for offshore wind turbines, and is divided into two lectures. The second lecture continues with the case of laterally loaded offshore piles, which bears most relevance for the case of the monopile foundations. Here again, a clear separation between physical reality and design methods is intended. Finally, the last part of the second lecture introduces several advanced topics which lie outside the classical design approaches, namely the hydromechanical coupling effects (i.e. the excess pore-pressure generation around the monopiles), the cyclic pile fatigue and the so-called pile setup (i.e. the time effects on the axial pile capacity). The relevance of the latter two topics is illustrated with experimental results from a field testing campaign on real large-scale piles. T2 - CEDEX-UNED 2021 Master course on Soil Mechanics and Geotechnical Engineering CY - Online meeting DA - 24.03.2021 KW - Offshore wind energy KW - Deep foundations KW - Offshore geomechanics KW - Lateral load bearing KW - Cyclic degradation KW - Pile ageing PY - 2021 AN - OPUS4-52342 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Cuéllar, Pablo T1 - Deep foundations for offshore wind turbines. Part 1: Axial behaviour T1 - Cimentaciones profundas para aerogeneradores marinos. Parte 1: Comportamiento axial N2 - This presentation deals with the phenomenology and design of pile foundations for offshore wind turbines, and is divided into two lectures. The first lecture presents a brief introduction to the context and peculiarities of such foundations, and then focuses on the particular case of axially loaded piles. This part is most relevant for the relatively slender piles of the multi-pile substructures (i.e. jackets and tripods). A clear distinction between physical phenomenology and practical design is drawn here. T2 - CEDEX-UNED 2021 Master course on Soil Mechanics and Geotechnical Engineering CY - Online meeting DA - 24.03.2021 KW - Offshore wind energy KW - Deep foundations KW - Offshore geomechanics KW - Axial load bearing KW - Design models PY - 2021 AN - OPUS4-52341 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Cuéllar, Pablo T1 - Deep foundations for offshore wind turbines. Lecture 1: Axial behaviour T1 - Cimentaciones profundas para aerogeneradores marinos - Parte 1: Comportamiento axial N2 - This presentation deals with the phenomenology and design of pile foundations for offshore wind turbines, and is divided into two lectures. The first lecture presents a brief introduction to the context and peculiarities of such foundations, and then focuses on the particular case of axially loaded piles. This part is most relevant for the relatively slender piles of the multi-pile substructures (i.e. jackets and tripods). A clear distinction between physical phenomenology and practical design is drawn here. T2 - Masters course on Soil Mechanics and Geotechnical Engineering. Geotechnical Laboratory of CEDEX CY - Online meeting DA - 21.04.2020 KW - Pile foundations KW - Offshore wind turbines KW - Physical phenomenology KW - Design methods PY - 2020 AN - OPUS4-51057 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Cuéllar, Pablo T1 - Deep foundations for offshore wind turbines. Lecture 2: lateral behaviour and advanced topics T1 - Cimentaciones profundas para aerogeneradores marinos - Parte 2: Comportamiento lateral y tematica avanzada N2 - This presentation deals with the phenomenology and design of pile foundations for offshore wind turbines, and is divided into two lectures. The second lecture continues with the case of lateraly loaded offshore piles, which bears most relevance for the case of the monopile foundations. Here again, a clear separation between physical reality and design methods is intended. Finally, the last part of the second lecture introduces several advanced topics which lie outside the classical design approaches, namely the hydromechanical coupling effects (i.e. the excess pore-pressure generation around the monopiles), the cyclic pile fatigue and the so-called pile setup (i.e. the time effects on the axial pile capacity). The relevance of the latter two topics is illustrated with experimental results from a field testing campaign on real large-scale piles. T2 - Masters course on Soil Mechanics and Geotechnical Engineering. Geotechnical Laboratory of CEDEX CY - Online meeting DA - 21.04.2020 KW - Pile foundations KW - Offshore wind turbines KW - Physical phenomenology KW - Design methods PY - 2020 AN - OPUS4-51059 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Cuéllar, Pablo T1 - State of the art and development perspectives of deep foundations for offshore wind converters T1 - Estado del arte y perspectivas de desarrollo de las cimentaciones profundas para aerogeneradores offshore N2 - This presentation provides an overview of the main geotechnical aspects associated with deep foundations in the context of offshore wind generation. The most common deep foundation typologies (large diameter monopiles and multipile typologies) as well as new trends under development (e.g. suction buckets) and their current limits will be briefly described. The talk concludes with a brief review of advanced topics not covered in classical pile design, such as hydromechanical coupling effects (pore pressure generation), cyclic accumulation of deformations, cyclic degradation of axial capacity or pile-setup gains. T2 - Ciclo de Conferencias: Aplicaciones de la Geotecnia en la generación de Energía. Sociedad Argentina de Ingeniería Geotécnica SAIG CY - Online meeting DA - 02.12.2020 KW - Offshore wind energy KW - Deep foundations KW - Offshore geomechanics PY - 2020 AN - OPUS4-51729 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Cuéllar, Pablo T1 - An efficient GPU implementation of a micromechanical computational tool for erosion problems N2 - We present here a set of conceptual and numerical tools for a micromechanical simulation of general erosion problems involving fluid-saturated granular assemblies, whether frictional or cohesive. We propose a parallel computation using graphical processing units (GPUs) to treat large numbers of degrees of freedom with conventional desktop computers. The fluid phase is here simulated with a particle-resolved approach in the frame of the Lattice Boltzmann Method (LBM) while the granular solid phase is modelled as a collection of discrete particles from a Molecular Dynamics DEM perspective. The range of possible material behaviors for the solid granular phase is intended here to cover a broad spectrum from purely frictional to viscous cohesive materials with either brittle or transient debonding features. Specific details of the implementation and some validation cases will be put forward. To conclude we provide some exemplary applications in the field of soil erosion along with details on the parallel performance of the models. The results show that a micromechanical approach can be feasible and useful in practice, providing meaningful insights into complex phenomena like the erosion threshold and kinetics of weakly cemented soils. T2 - EWG-IE 2020 Workshop on "Innovative numerical methods for internal erosion processes" CY - Online meeting DA - 17.12.2020 KW - Erosion KW - Earthen hydraulic constructions KW - Micromechanical modelling KW - LBM-DEM coupling KW - GPU parallel computation PY - 2020 AN - OPUS4-51866 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Cuéllar, Pablo T1 - Design challenges for Offshore wind-farms. From foundation mechanics to wind-farm aerodynamics N2 - This talk provides a brief introduction on general engineering design challenges for the offshore wind energy production. Some general features of the offshore wind-energy field from a civil engineering perspective are firstly presented, followed by a brief discussion of some of the main geomechanical issues for the foundation of the offshore turbines into the seabed. In the following part, an overview of relevant fluid-structure interactions and some options for an efficient numerical analysis are provided, where the hydromechanical Wave–Tower interaction is firstly discussed. Then, some general aspects of the windfarm aerodynamics are introduced. On the one hand, some modelling possibilities for the wake analysis of single turbines and turbine groups are discussed. And on the other hand the relevance of such analyses for a proper windfarm layout optimization is pointed out. In particular, this talk shows that: i) The bearing capacity of turbine multi-pile foundations can degrade under cyclic loading (waves, wind, …), while for monopile foundations cyclic hydromechanical coupling effects may take place, which may lead to a foundation softening; ii) Numerical analysis of a turbine’s interaction with wind/waves is useful and affordable, while simplified models can already provide a useful insight into the windfarm aerodynamics. iii) Turbulent wake analysis is very relevant for the windfarm layout. T2 - Colloquium "Energy systems compared", Winter semester 20/21, Faculty of Physics CY - Online meeting DA - 21.01.2021 KW - Offshore wind energy KW - Marine geotechnics KW - Fluid-structure interaction KW - Numerical modelling PY - 2021 AN - OPUS4-52038 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Cuéllar, Pablo T1 - Design challenges for Offshore wind-farms. From foundation mechanics to wind-farm aerodynamics N2 - This talk provides a brief introduction on general engineering design challenges for the offshore wind energy production. Some general features of the offshore wind-energy field from a civil engineering perspective are firstly presented, followed by a brief discussion of some of the main geomechanical issues for the foundation of the offshore turbines into the seabed. In the following part, an overview of relevant fluid-structure interactions and some options for an efficient numerical analysis are provided, where the hydromechanical Wave–Tower interaction is firstly discussed. Then, some general aspects of the windfarm aerodynamics are introduced. On the one hand, some modelling possibilities for the wake analysis of single turbines and turbine groups are discussed. And on the other hand the relevance of such analyses for a proper windfarm layout optimization is pointed out. In particular, this talk shows that: i) The performance and behavior of the turbine's foundation is often conditioned by the appearance of large deformations, fluid couplings and grain-scale phenomena, whereby specific physical testing (both in field and lab conditions) and ad-hoc simulation techniques can provide useful insights for design; ii) Numerical analysis of a turbine’s interaction with wind/waves is already affordable in engineering scales, while simplified models can already provide a useful insight into the windfarm aerodynamics. iii) Turbulent wake analysis is very relevant for the windfarm layout. T2 - Colloquium "Energy systems compared", Winter semester 22/23, Faculty of Physics CY - Duisburg, Germany DA - 24.01.2023 KW - Offshore wind-turbine foundations KW - Water-structure interaction KW - Wind-farm aerodynamics PY - 2023 AN - OPUS4-56888 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Cuéllar, Pablo T1 - Deep foundations for offshore wind turbines - 1st part: axial behavior T1 - Cimentaciones profundas para aerogeneradores marinos. 1a parte: Comportamiento axial N2 - This presentation deals with the phenomenology and design of pile foundations for offshore wind turbines, and is divided into two lectures. The first lecture presents a brief introduction to the context and peculiarities of such foundations, and then focuses on the particular case of axially loaded piles. This part is most relevant for the relatively slender piles of the multi-pile substructures (i.e. jackets and tripods). A clear distinction between physical phenomenology and practical design is drawn here. T2 - Masters course on Soil Mechanics and Geotechnical Engineering. Geotechnical Laboratory of CEDEX CY - Online meeting DA - 17.03.2023 KW - Pile foundations KW - Offshore wind turbines KW - Physical phenomenology KW - Design methods KW - Numerical modelling KW - Physical testing PY - 2023 AN - OPUS4-57176 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Cuéllar, Pablo T1 - Deep foundations for offshore wind turbines - 2nd part: lateral behavior & advanced topics T1 - Cimentaciones profundas para aerogeneradores marinos. 2a parte: Comportamiento Lateral + Temática avanzada N2 - This presentation deals with the phenomenology and design of pile foundations for offshore wind turbines, and is divided into two lectures. The second lecture continues with the case of laterally loaded offshore piles, which bears most relevance for the case of the monopile foundations. Here again, a clear separation between physical reality and design methods is intended. Finally, the last part of the second lecture introduces several advanced topics which lie outside the classical design approaches, namely the hydromechanical coupling effects (i.e. the excess pore-pressure generation around the monopiles), the cyclic pile fatigue and the so-called pile setup (i.e. the time effects on the axial pile capacity). The relevance of the latter two topics is illustrated with experimental results from a field testing campaign on real large-scale piles. T2 - Masters course on Soil Mechanics and Geotechnical Engineering. Geotechnical Laboratory of CEDEX CY - Online meeting DA - 17.03.2023 KW - Pile foundations KW - Offshore wind turbines KW - Physical phenomenology KW - Design methods KW - Numerical modelling KW - Physical testing PY - 2023 AN - OPUS4-57178 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Degener, Sebastian T1 - Load Identification and Damage Detection by a Digital Twin of a Bridge applying Bayesian Model Calibration N2 - A digital twin for decision making during the life cycle of civil infrastructure is a promising concept combining simulation models with corresponding structure-specific sensor data to support maintenance decisions or to investigate the reliability. The sensor data quality as well as the model quality of the digital twin, comprising on modeling assumptions and correct model parameters strongly influences the prognosis results. T2 - 10th European Workshop on Structural Health Monitoring (EWSHM 2024) CY - Potsdam, Germany DA - 10.06.2024 KW - Load identification KW - Damage detection KW - Digital Twin KW - Bayesian Model Calibration KW - Bridge model PY - 2024 AN - OPUS4-62186 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Eichner, Lukas T1 - Design of offshore jacket support structure for experimental fatigue life evaluation N2 - One crucial metric of interest to wind farm operators is the remaining useful life (RUL) of single components, wind turbines, or even entire wind farms. Occasionally, questions arise regarding how to operate a turbine, even in the presence of manufacturing or design errors, which from a computational design standpoint reduce the remaining lifetime below the intended service life. A typical measure involves adapting the monitoring and inspection plan. Using such a maintenance plan, the author intends to simulate the lifetime of jacket-type structure in a fatigue test. The objective of the experiment is to demostrate that systems like three-dimensional jackets possess redundancies that enable reliable continued operation, despite the reduced fatigue life of individual components due to technical flaws, if an appropriate maintenance concept is in place. This presentation discusses the steps leading to the procedure of the experiment including the design process and the maintenance planning. T2 - 19th eawe PhD Seminar CY - Hannover, Germany DA - 06.09.2023 KW - Offshore wind energy KW - Jacket support structure KW - Simulation and experiment KW - Structural integrity management KW - Risk-based maintenance planning PY - 2023 AN - OPUS4-58240 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Eichner, Lukas T1 - LUKAS’ JACKET: A test structure for model and monitoring based lifetime management of offshore jacket support structures N2 - The goal of the experiments is to demonstrate that systems like three-dimensional jackets possess redundancies that, despite the reduced fatigue life of individual components, enable reliable operation if an appropriate maintenance concept is in place. In practice, individual potentially faulty components in the structure have been handled conservatively so far. To move away from this approach, methods and strategies in the field of life cycle management that enable economically optimal and reliable operation must be transferred from scientific research to practice. Experiments are the preferred method to establish the proof of concept. To realistically simulate the operational lifetime of a jacket structure through an experiment, cyclic loads must be applied to the structure to replicate typical fatigue processes. To ensure that the test structure is not a "disposable product" and can undergo multiple test cycles, the experimental concept includes system-level and component-level tests. The latter are conducted on removable joints. These elements at the nodes of the structure have been manufactured in multiple variations, both to potentially contain mentioned flaws and to undergo more load cycles individually than the main structure. Once the removable joint is sufficiently pre-damaged and thus the reduced remaining fatigue life is established, the element is inserted into the overall structure. The defined maintenance strategy is then implemented on the entire system. This strategy consists of structural health monitoring (SHM), inspections, and repairs. At defined intervals, cyclic loading is interrupted to apply dynamic loads. Using the installed monitoring system and coupled operational modal analysis (OMA), the modal parameters of the structure are determined, which can help identify potential system damage. Optimal sensor placement (OSP) can be determined based on a maximum value of information (VoI) across the entire pre-posterior predicted service life. For detailed investigations at the hotspots, inspections are conducted using non-destructive methods, among others. Overall global and local information about the structure's condition is gathered these methods, which are then incorporated into models describing the structure through Bayesian updating. This allows for initial system identification based on different system responses and later updating of the predicted parameters of analytical and numerical models. Utilizing the updated models, decisions regarding maintenance actions, such as further inspections or repairs, are made, which are subject to uncertainties. The probabilistic models enable a reliability- and risk-based maintenance strategy, where, for example, maximum failure rates can act as triggers for maintenance actions. These decisions are relevant for the planned duration of the simulated operational lifetime, as well as for potential lifetime extensions, which are currently of significant importance in practice. Optimizing the maintenance strategy for the operational lifetime of the structures with these methods will lead to a higher utility of the offshore wind farm. The work associated with the test structure encompasses a variety of topics (including fatigue, damage detection and identification, reliability, Bayesian updating, system identification, SHM, maintenance planning, decisions under uncertainties), which are integrated through corresponding models and methods. All these models have been and are being applied in the numerical accompaniment of the experiments. By applying them to a structure that includes the relevant locations and aspects of real-world structures, both well-functioning and suboptimal parts of the established framework will be revealed. T2 - 20th EAWE PhD Seminar on Wind Energy CY - Visby, Sweden DA - 23.09.2024 KW - Offshore Jacket Support Structure KW - Test Structure KW - Fatigue KW - Lifetime Management KW - Structural Health Monitoring PY - 2024 AN - OPUS4-61146 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -