TY - CONF A1 - Auersch, Lutz T1 - Four typical errors in train induced ground vibration and ground vibration mitigation N2 - Mitigation measures of railway induced vibration have been demonstrated at the emission, transmission and immission part. It must be carefully observed that the correct masses and stiffnesses are used. Typical mistakes have been shown, - 1D models for vehicle-track interaction, - impedance instead of stiffness for the infill material of a trench, - rigid buildings or neglecting the soil-building interaction. The dominant mid-frequency part of the ground vibration is due to the irregular soil. T2 - ISO/TC 108/SC 2/WG 8 Working group Ground-borne noise and vibration from rail systems CY - Milano, Italy DA - 14.10.2019 KW - Ground vibration KW - Train excitation KW - Mitigation PY - 2019 AN - OPUS4-49446 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz T1 - Berechnung und Beeinflussung von Deckeneigenfrequenzen N2 - Es werden Erfahrungen zur Berechnung von Deckeneigenfrequenzen aus zahlreichen Projekten zusammengetragen. T2 - Projektbesprechung zum Hotelneubau CY - Berlin, Germany DA - 10.07.2019 KW - Deckeneigenfrequenzen PY - 2019 AN - OPUS4-49448 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Cuéllar, Pablo A1 - Benseghier, Z. A1 - Luu, L.-H. A1 - Bonelli, S. A1 - Philippe, P. 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 - Nerger, Deborah A1 - Moosavi, Robabeh A1 - Bracklow, F. A1 - Hering, M. A1 - Kühn, T. A1 - Curbach, M. A1 - Hille, Falk A1 - Rogge, Andreas T1 - Impact damage characterization at RC plates with planar tomography and FEM N2 - Prediction of dynamic effects of reinforced concrete structures under impact loading is a technical challenge. This is a consequence of the great variability of the physical properties resulting from the wide adaptability of reinforced concrete and a consequence of the wide range of impact loading. Experiments and numerical investigations are normally used on a small scale to address the problem. In this paper, impact tests on reinforced conrete plates with the lateral dimensions of 1.5 m x 1.5 m and a thickness of 30 cm are presented. In bending reinforcement, besides the velocity two properties are varied, the diameter and the spatial distribution of the rebars. Experiments are performed at the Otto-Mohr-Laboratory of the Institute of Concrete Structures of the Technische Universit¨at Dresden. Due to the accelerated fall of the impactor the velocity ranges between 20 and 70 m/s. In addition to the measured quantities such as bearing forces, accelerations are also measured at 4 different positions on and under the plate, as well as the deflection at several positions. The measured data are used for the analysis of the damage form and the numerical examinations with the program Ansys Autodyn and the material model after Drucker-Prager. Numerical investigations support the tests, with detailed analysis of individual effects. These numerical computations and the planar tomographic investigations were carried out at BAM in Berlin. With the help of planar tomographic evaluation, the damaged structure is made visible and compared with the numerical results. Influences of the bending reinforcement are explained on the basis of damage evaluation in the local area and on selected measured values. In addition to the test evaluation, the tomographic and numerical methods are presented. T2 - XI International Conference on Structural Dynamics (EURODYN 2020) CY - Online meeting DA - 23.11.2020 KW - Post-impact evaluation KW - Damage characterization KW - Planar tomography KW - Drucker-Prager KW - Ansys Autodyn PY - 2020 AN - OPUS4-51768 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz A1 - Ziemens, Susanne T1 - The response of different buildings to free-field excitation – a study using detailed finite element models N2 - A study on building vibrations has been performed by finite element calculations. Family houses, multi-storey residential buildings, office buildings and office towers have been modelled in detail. The frequency-dependent response due to a free-field excitation has been evaluated for walls, columns and floors. The ratio of building amplitudes to free-field amplitudes starts with uB/u0 = 1 at zero frequency and is usually lower than 1 at 50 Hz, the end of the frequency range considered here. In between, amplifications occur due to several reasons. There are „soil resonances“ where the whole building is vibrating on the compliant soil, “column resonances” where the upper storeys are vibrating on the compliant columns, and the “floor resonances” where the floors are vibrating excited by their supports. Results are presented for all building types, but a special focus is set on office buildings. A parameter study shows the influence of the stiffness of the soil, the number of storeys, and the width of the building. It has been found that the “soil resonance” is strongly modified by the low-frequency floor resonances for the normal office building. The main resonance of a twenty-storey office tower is determined equally by the “soil mode” and the “column mode”. It is an important observation for these office buildings that the resonances can differ for different parts of the building such as the centre, the edge, the corner, and the core of the building. This leads to non-uniform vibration modes across the building, which look like another type of “floor resonance” and which have been observed in several real building projects. Experimental results will be shown which can confirm the calculated phenomena. T2 - EURODYN 2020 XI International Conference on Structural Dynamics CY - Online meeting DA - 23.11.2020 KW - Building vibration PY - 2020 AN - OPUS4-51679 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Frei, Vivian A1 - Thiele, Marc A1 - Pirskawetz, Stephan A1 - Meng, Birgit A1 - Rogge, Andreas T1 - Characterizing the Fatigue Behavior of High-Performance Concrete for Wind Energy Structures N2 - Severe mechanical fatigue conditions for worldwide proliferating windfarms are a Major challenge for high-performance concrete in towers, connecting joints and foundations of wind turbines. High-performance concrete offers potential for the application in offshore windfarms, not only regarding its good mechanical, but also chemical resistivity due to low diffusivity in the highly densified microstructure. For a more reliable fatigue assessment, monitoring based on nondestructive testing can be a valuable complement to design rules. Both approaches demand reliable experimental data, information about scalability and the development of standardized testing methods. This article presents results of an ongoing research program of BAM (Bundesanstalt für Materialforschung und -prüfung), which is a part of a joint national project (WinConFat) funded by the German Federal Ministry for Economic Affairs and Energy. The subproject implemented by BAM examines the fatigue behavior in dependence of size and slenderness for varying concrete strength at different stress levels. Besides fatigue strength, nondestructive testing is carried out additionally. Methods used are strain measurement and ultrasonic testing. The change of strain, stiffness and ultrasonic pulse velocity in the fatigue process is discussed. Results disclose a deeper insight into the damage process under cyclic loading of high-performance concrete and contribute to improve nondestructive monitoring. T2 - LORCENIS - Long Lasting Reinforced Concrete for Energy Infrastructue under Severe Operating Conditions CY - Gent, Belgium DA - 10.09.2019 KW - Compressive Cyclic loading KW - Fatigue KW - High-strength concrete KW - Non destructive testing KW - Ultrasonic testing PY - 2019 AN - OPUS4-49474 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Nerger, Deborah A1 - Hille, Falk A1 - Moosavi, Robabeh A1 - Grunwald, Marcel A1 - Redmer, Bernhard A1 - Kühn, T. A1 - Hering, M. A1 - Bracklow, F. T1 - Post-impact evaluation at RC plates with planar tomography and FEM N2 - Due to the many possible applications, the uncomplicated production and the high application range, reinforced concrete is a widely used building material. This large range of physical material properties still poses an engineering challenge in determining all necessary requirements for predicting dynamic effects under impact load. Many aspects of impact have already been examined and some correlations have been studied intensively. Examples are the work of Lastunen and Booker, who studied the influence of projectile properties on the impact form. Li has also investigated the local effects of an impact. The field of detailed damage analysis has not been in focus so far. This presentation shows some studies in medium-velocity impact with the focus on post-impact damage evaluation. The impactor is modified so that the test plates show low penetration on the top and scabbing on the bottom. With the unique tomography lab test stand at BAM the plate is scanned after the impact and the damage is analyzed. Cracks and scabbing are made visible with a reconstruction. The comparison of simulation and tomography allows to create prognosis models for damage characterization. T2 - 36th Danubia Adria Symposium on Advances in Experimental Mechanics CY - Pilsen, Czech Republic DA - 24.09.2019 KW - Impact KW - Damage characterization KW - Planar tomography KW - Numeric simulation KW - Reinforced concrete structure PY - 2019 AN - OPUS4-49691 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz T1 - Zur Berechnung der Erschütterungsminderung von Eisenbahngleisen mit ein- und zweidimensionalen Modellen N2 - Eindimensionale Modelle des Gleises aus einem Schienenstützpunkt, zweidimensionale Modelle enthalten die Kraftverteilung der Schiene. Eindimensionale Modelle machen einen Fehler, weil sie eine zu große Fahrzeugmasse berücksichtigen. Man kann jedoch bei der Berechnung der Minderungswirkung von Gleiselementen eindimensionale Gleismodelle verwenden, um die Kraftübertragung des Gleises bzw. die Minderungswirkung des Gleises zu berechnen. Die Wechselwirkung mit dem Fahrzeug kann einfach mit der dynamischen Stützpunktsteifigkeit berechnet werden. Dabei muss die Stützpunktsteifigkeit mit einer charakteristischen Gleislänge multipliziert werden, die frequenz- und systemabhängig ist. T2 - Norm-Arbeitsausschuss Schwingungsminderung in der Umgebung von Verkehrswegen CY - Munich, Germany DA - 14.01.2020 KW - Richtige Fahrzeugmasse KW - Erschütterungsminderung KW - Elastische Gleiselemente KW - Rechenverfahren PY - 2020 AN - OPUS4-50268 LA - deu 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 - Herrmann, Ralf A1 - Hille, Falk A1 - Said, Samir A1 - Sterthaus, Jens A1 - Müller, Karsten A1 - Quercetti, Thomas A1 - Wille, Frank A1 - Paffenholz, J.-A. A1 - Baeßler, Matthias T1 - Implementing a Structural Health Monitoring System using Digital Models of the BAM Large Drop Test Facility N2 - At the Bundesanstalt für Materialforschung und -prüfung (BAM) full scale specimens for nuclear transport and storage containers (casks) are tested for their structural integrity in a series of drop tests on the Test Site Technical Safety in Horstwalde, 50 km south of Berlin. These drop tests cause a major stress not only on the casks, but also on the steel tower structure of the test facility, itself. The load pattern makes the structure very interesting for detailed investigation. The focus of the monitoring lies on the bolted joints of the flange connections that are a typical connection for cylindrical elements if welding is technical or economical unfavorable. The definition of the monitoring takes was done by investigating the existing documents and inspection results accompanied by building an initial digital representation of the structure, consisting of two finite element (FE) models and a geometrical 3D point cloud representation. As a first step the structures behavior during static and dynamic loading was analyzed using measurement data and an updated numerical FE Model. The idea behind is to use models for a digital planning and operation/evaluation of the structural health monitoring. A static FE simulation and a dynamic FE simulation are generated, to investigate how the structure behaves under the load conditions. T2 - XI International Conference on Structural Dynamics (EuroDyn 2020) CY - Online meeting DA - 23.11.2020 KW - Structural Health Monitoring KW - System Identification KW - Digital Twin KW - Point Cloud KW - Drop Test PY - 2020 AN - OPUS4-51734 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 - Viefhues, Eva A1 - Döhler, M. A1 - Hille, Falk A1 - Mevel, L. T1 - Fault detection for linear parameter varying systems under changes in the process noise covariance N2 - Detecting changes in the eigenstructure of linear systems is a comprehensively investigated subject. In particular, change detection methods based on hypothesis testing using Gaussian residuals have been developed previously. In such residuals, a reference model is confronted to data from the current system. In this paper, linear output-only Systems depending on a varying external physical parameter are considered. These systems are driven by process noise, whose covariance may also vary between measurements. To deal with the varying parameter, an interpolation approach is pursued, where a limited number of reference models { each estimated from data measured in a reference state { are interpolated to approximate an adequate reference model for the current parameter. The problem becomes more complex when the different points of interpolation correspond to different noise conditions. Then con icts May arise between the detection of changes in the eigenstructure due to a fault and the detection of changes due to different noise conditions. For this case, a new change detection approach is developed based on the interpolation of the eigenstructure at the reference points. The resulting approach is capable of change detection when both the external physical parameter and the process noise conditions are varying. This approach is validated on a numerical simulation of a mechanical system. T2 - 21st IFAC World Congress CY - Berlin, Germany DA - 13.07.2020 KW - Linear parameter varying systems KW - Fault detection KW - Changing process noise KW - Subspace-based residual KW - Model interpolation PY - 2020 AN - OPUS4-52366 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. 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 - Baeßler, Matthias A1 - Zobel, D. A1 - Cuéllar, Pablo A1 - Geißler, Peter A1 - Hüsken, Götz A1 - Grabe, J. T1 - Improvement of the Bearing Capacity of Offshore Pile Foundations N2 - The Presentation gives an overview about Background, Needs and challenges with respect to pile design and modular pile capacity increase in the Frame of Offshore-Wind Foundations. Results and ideas of the Project TOP are presented. The presentation is prepared jointly by TUHH and BAM. T2 - Offshore Wind R&D Conference 2018 CY - Bremerhaven, Germany DA - 14.11.2018 KW - Grout Injection KW - Pile Capacity KW - TOP PY - 2018 AN - OPUS4-46626 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Benseghier, Z. A1 - Cuéllar, Pablo A1 - Luu, L.-H. A1 - Bonelli, S. A1 - Philippe, P. T1 - Parallel LBM-DEM simulation of fluid flow erosion using GPU N2 - Surface erosion of a cohesive granular soil by a fluid flow is investigated numerically by coupling the Lattice Boltzmann Method (LBM) for the fluid phase and the Discrete Element Method (DEM) for describing the motion of the solid particles. In addition, inter-particles cohesion is insured by a contact model featuring a paraboloidal yield surface. The use of a fully resolved LBM-DEM coupling technique is currently limited due to the computational cost when simulating a large number of particles. This issue can be overcome using the graphics processing unit (GPU) thanks to ist massively parallel hardware architecture. Here, we first present a 2D GPU implementation of LBM-DEM coupling for a granular assembly. The GPU implementations are approximatively 30 times faster than a single core CPU version. Then, we apply the parallelization technique to practical erosional cases, namely the jet erosion test (JET) and the shear-driven erosion by a Couette flow. These numerical tests aim to relate micro parameters of a cohesive material (eg. cohesion) to macro parameters (eg. soil erodibility, mechanical strengths). Preliminary results show that micromechanical features indeed provide a novel insight of soil erosion phenomena. T2 - CILAMCE 2018 CONGRESS CY - Paris/Compiègne, France DA - 11.11.2018 KW - Micromechanical LBM-DEM simulation KW - GPU parallelisation KW - Soil erosion PY - 2018 AN - OPUS4-46594 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kullolli, Borana T1 - A generalized plasticity model adapted for shearing interface problems N2 - The response of many geotechnical systems, whose structural behavior depends on shearing effect, is closely related to soil structure interaction phenomenon. Experimentally it is found that the localisation of these effect happens at a narrow soil layer next to the structure. Numerically, this behavior can be modelled through interface elements and adequate constitutive models. In this work, a constitutive model in the framework of Generalized Plasticity for sandy soils has been chosen to be adapted for the interface zone. From the direct shear experiments a sandy soil at loose and dense states under different normal pressures is considered. The adapted constitutive model is able to reproduce contraction and dilatation of the soil according to its relative density and it shows a good agreement with the experimental data. T2 - Numerical Geotechnics CY - Porto, Portugal DA - 25/06/2018 KW - Interface model KW - Cyclic axial shearing KW - Numerical model PY - 2018 AN - OPUS4-47068 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Mevel, L. A1 - Viefhues, Eva A1 - Döhler, M. A1 - Hille, Falk T1 - Asymptotic analysis of subspace-based datadriven residual for fault detection with unceratin reference N2 - The local asymptotic approach is promising for vibration-based fault diagnosis when associated to a subspace-based residual function and efficient hypothesis testing tools. It has the ability of detecting small changes in some chosen system parameters. In the residual function, the left null space of the observability matrix associated to a reference model is confronted to the Hankel matrix of output covariances estimated from test data. When this left null space is not perfectly known from a model, it should be replaced by an estimate from data to avoid model errors in the residual computation. In this paper, the asymptotic distribution of the resulting data-driven residual is analyzed and its covariance is estimated, which includes also the covariance related to the reference null space estimate. The importance of including the covariance of the reference null space estimate is shown in a numerical study. T2 - 10th IFAC Symposium on Fault Detection, Supervision and Safety for Technical Processes SAFEPROCESS 2018 CY - Warsaw, Poland DA - 29.08.2018 KW - Fault detection KW - Uncertainty in reference KW - Residual evaluation KW - Statistical tests KW - Vibration measurement PY - 2018 AN - OPUS4-46505 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Baeßler, Matthias A1 - Hille, Falk T1 - Strategies for discriminating environmental from damage based variations in monitoring data N2 - Right from the beginning of applying SHM to bridge structures it was obvious that environmental based perturbations on the measurement significantly influence the ability to identify structural damage. Strategies are needed to classify such effects and consider them appropriately in SHM. Various methods have been developed and analyzed to separate environmental based effects from damage induced changes in the measures. Generally, two main approaches have emerged from research activity in this fields: (a) statistics based tools analyzing patterns in the data or in computed parameters and (b) methods, utilizing the structural model of the bridge taking into account environmental as well as damage based changes of stiffness values. With the back-ground of increasing affordability of sensing and computing technology, effort should be made to increase sensitivity, reliability and robustness of procedures, separating environmental from damage caused changes in SHM measures. The contribution describes both general strategies and points out their Advantages and drawbacks. As basis, a review on relevant methods was conducted. The aim of the study is to classify approaches for separating damage describing information from environmental based perturbations in dependency of the SHM objective. And such, it is intended to describe a best practice in designing concepts for Monitoring infrastructure, naturally effected by environmental influences. T2 - IABMAS 2018 CY - Melbourne, Australia DA - 09.07.2018 KW - SHM KW - Environmental PY - 2018 AN - OPUS4-46060 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz T1 - Wellenausbreitung in geschichteten Böden – Rechenmethoden und Messbeispiele von Zug- und Gebäudeerschütterungen N2 - Im ersten Teil werden Methoden der Wellenanalyse vorgestellt, Seismogramme, Multistation Analysis of Surface Waves (MASW), f,v-Analyse (Dispersion aus zweifacher Fourier-Analyse), Spatial AutoCorrelation (SPAC, hier auch für deterministische Quellen), und auf Messungen in Deutschland, Österreich und der Schweiz angewendet. Mit den Wellengeschwindigkeiten des Bodens werden die Berechnungsgrundlagen für die Erschütterungsausbreitung im Boden und die Bauwerk-Boden-Wechselwirkung geschaffen. Der zweite Teil beschäftigt sich mit der Wellensynthese, das heißt mit der Berechnung von Wellenfeldern (aus Wellenzahlintegralen). Die Rechnungen können wesentlich vereinfacht werden, wenn man die Dimensionsanalyse und Symmetrieüberlegungen ausnutzt, so dass maximal fünf dimensionslose Verschiebungsfunktionen verbleiben (im Vollraum sind es sogar nur zwei Verschiebungsfunktionen, die sich einfach explizit angeben lassen). Es gibt Ähnlichkeiten zwischen den Halbraum-Amplituden an der Oberfläche, den Halbraum-Amplituden in der Tiefe und der Wellenausbreitung im Vollraum. Die berechneten Wellenfelder (als Terzspektren in verschie-denen Entfernungen von der Erschütterungsquelle) werden verwendet, um die gemessene Übertragungsfunktionen des Bodens zu approximieren und Erschütterungen von Zugvorbeifahrten zu prognostizieren. Auch dies wird an einigen Messorten vorgeführt. Dabei werden einige gemessene Besonderheiten der Eisenbahnerschütterungen mit dem geschichteten Aufbau des Bodens erklärt. Der dritte Teil beschäftigt sich mit der Anwendung der Wellenfelder beziehungsweise der Punkt-lastlösungen beziehungsweise der Greenschen Funktionen in der Randelementmethode. Es wird ein einfaches Prinzip der Herleitung der Randelementmethode vorgeführt. Bei einer beliebigen Berandung benötigt man neben den Verschiebungswellenfeldern auch die Spannungswellen-felder. Eine einfache Berechnung der Spannungswellenfelder wird vorgeführt, die im Vollraum auf drei Spannungsfunktionen, ähnlich einfach wie die Verschiebungsfunktionen, führt. Durch die Kopplung der Randelementmethode mit der Finite-Element-Methode können dann Probleme der Bauwerk-Boden-Wechselwirkung gelöst werden. Der vierte Teil beschäftigt sich schließlich mit der Freifeld-Wellenanregung unter einem Gebäude und der Wellenanregung im Gebäude. Dabei geht es um die Wechselwirkung der Freifeldwellen mit starren oder flexiblen Fundamenten (Pfählen, Fundamentplatten) und den Übertragungs-faktoren zwischen dem Freifeld und dem Gebäude. Bei der Wellenanregung in einem Büro-gebäude in Wien konnten die gleichen Methoden wie bei der Wellenanregung im Boden eingesetzt werden, Seismogramme, MASW, Übertragungsfunktionen und Amplituden-Abstandsgesetze. T2 - Festkolloquium Baudynamik CY - Graz, Austria DA - 05.10.2018 KW - Dispersionsmessung KW - Wellenfeldberechnung KW - Erschütterungsprognose KW - Randelementmethode KW - Bauwerk-Boden-Wechselwirkung KW - Deckenschwingungen PY - 2018 AN - OPUS4-46403 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Song, Jiaojiao A1 - Auersch, Lutz T1 - Track-soil calculation and measurement of damaged and repaired slab tracks N2 - Calculation of the behaviour of damaged slab tracks have been performed with ANSYS and with a combined finite-element boundary-element Programme. Different damage lengths have been analysed and the best fit to the measurements has been chosen. T2 - Seminar on Railway Engineering CY - Tongji University Shanghai, People's Republic of China DA - 21.09.2018 KW - Slab track KW - Track damage KW - Boundary element method KW - Train passage PY - 2018 AN - OPUS4-46405 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Frei, Vivian A1 - Pirskawetz, Stephan A1 - Thiele, Marc A1 - Rogge, Andreas T1 - Experimental investigation of size effect on fatigue behavior of high strength concrete - concept and preliminary results N2 - The worldwide spread of windfarms brings new challenges, especially for concrete structures as a part of towers, connecting joints and foundations of wind turbines. High-cyclic loadings in such structures lead to a high relevance of the subject of fatigue. A proper assessment of the fatigue strength of concrete demands therefore a basis of reliable experimental data and the development of standardized testing methods. This article presents first results of an ongoing research program of BAM (Bundesanstalt für Materialforschung und -prüfung) which is a part of a joint project (WinConFat) funded by the German Federal Ministry for Economic Affairs and Energy. The subproject investigates the effects of size and slenderness of the specimens on the fatigue behaviour of high strength concrete at different stress levels. Not only the fatigue strength, but also the fatigue process itself is monitored by means of several measurement methods. Strain measurements are used to calculate the load dependent elastic modulus in the fatigue hysteresis as indicators for fatigue development. Furthermore, the application of non-destructive methods like acoustic emission analysis and ultrasonic measurement in laboratory tests gives a deeper insight into damage processes under cyclic loading. The results shall be used to improve design rules for concrete members under fatigue load and to develop or improve non-destructive techniques for in-service structural health monitoring. T2 - 5th International fib Congress: Better - Smarter - Stronger CY - Melbourne, Australia DA - 08.10.2018 KW - Acoustic emission testing KW - Compressive cyclic loading KW - Fatigue KW - High-strength concrete KW - Non-destructive testing KW - Size effect KW - Slenderness effect KW - Ultrasonic testing PY - 2018 AN - OPUS4-46366 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz T1 - Comparative measurements and calculations of ground vibrations near slab and ballast tracks N2 - Measurements of ground and track vibrations have been performed at a high-speed line in northern Germany. Impacts on the track and the ground, and passages of different trains with different speeds on different tracks have been measured. Transfer functions of the soil are presented and approximated by theoretical soil models. By using these transfer functions, the measured ground vibration between 2 to 64 m distance from the track can be transformed into a load spectrum which can be used for predictions at other sites. The method is compared to the soil-dependent method of an emission spectrum at a certain distance (8 m for example). The influence of train type, speed and track type is discussed on the base of the different emission quantities and the original measurements. The strong influence of the track, ballast track and slab track, is analysed by a theoretical model in wavenumber domain. The response of the track to the passage of the static load is reduced by the stiffness of the slab, the deformation of the track as well as the impulse acting on the soil. Usually, the impulse on the soil should result in a slow quasi-static movement of the soil, slower at further distances. In a heterogeneous soil, however, the impulses from the static loads scatter and keep parts of the higher impulse frequency band. In this case the reduced impulse spectra of the slab track will yield reduced ground vibration in a certain frequency band. Additional (BAM and international) measurements will be used to discuss this and possible other explanations for the different ground vibration differences. T2 - Railways 2018 CY - Sitges, Spain DA - 03.09.2018 KW - Ground vibration measurements KW - Train passages KW - Tran speed KW - Train configuration KW - Ballast track KW - Slab track PY - 2018 AN - OPUS4-46401 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hille, Falk A1 - Kowitz, Astrid A1 - Wu, Cheng-Chieh A1 - Helmerich, Rosemarie A1 - Kadoke, Daniel A1 - Gründer, Klaus-Peter A1 - Hauser, S. A1 - Schwarzinger, H. T1 - Impact on a micro-reinforced UHPC: experimental studies vs. numerical modeling N2 - Within the presented research project, experimental and numerical investigations were performed to develop a thin-shelled, modular, mobile element system made of a micro-reinforced ultra-high-performance ductile concrete (DUCON®). Material parameters were experimentally determined to adapt the material model within the numerical analysis applying the Drucker-Prager relationship. Afterwards, for validation of the numerical models, quasi-static and high-velocity impact tests were performed on plate-like structures. Finally, a suitable geometry of transportable barrier elements will be designed, which provides a maximum of resistance against impact by a minimum of weight and a maximum of mobility. T2 - 35th Danubia-Adria Symposium on Advances in Experimental Mechanics CY - Sinaia, Romania DA - 25.09.2018 KW - E-modulus KW - Quasi-static and dynamic tests KW - DUCON® KW - Impact KW - UHPC KW - Ductility KW - Micro-reinforcement KW - Mobile elements KW - Numerical modeling KW - Stereo photogrammetry KW - Compressive strength PY - 2018 AN - OPUS4-47003 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hille, Falk T1 - Unterraumbasierte Detektion von Strukturschäden an Jacket-Gründungen von Offshore-Windenergieanlagen N2 - Die vorliegende Arbeit beschreibt die Adaption eines globalen, schwingungsbasierten Verfahrens zur frühzeitigen Erkennung von Strukturschäden an Gründungsstrukturen offshore installierter Windenergieanlagen (OWEA). Damit soll es, Betreibern von Offshore-Windparks ermöglicht werden, im Rahmen periodisch durchgeführter messtechnischer Überwachungsmaßnahmen mit einem gegenüber wiederkehrender Inspektionen wesentlich geringen Aufwand auftretende Schäden an der Struktur zuverlässig zu delektieren. Das untersuchte und implementierte Verfahren basiert auf der Methode der stochastischen unterraumbasierten Schadensdetektion. Dabei erfolgt eine statistische Analyse des wiederkehrend messtechnisch aufgenommenen dynamischen Antwortverhaltens des mechanischen Systems. Mittels statistischem Test werden signifikante Änderungen in dessen Eigenstruktur und damit Schäden delektiert. Im Rahmen der vorliegenden Arbeit wurden umfangreiche experimentelle als auch numerische Untersuchungen zur Sensitivität und Robustheit des beschriebenen Schadensindikators durchgeführt. Dazu sind zunächst an einem Labormodell mittels künstlich und reversibel eingebrachter Schäden grundlegende Analysen zu den Einflüssen signal- und verfahrensinhärenter Kenngrößen durchgeführt worden. Auf der Basis dieser Ergebnisse wurde im Anschluss mittels numerischer Analysen das Antwortverhalten von OWEA simuliert und der entwickelte Algorithmus zur Schadensdetektion an den so realisierten Datensätzen angewendet. Anhand der Ergebnisse der Arbeit wird aufgezeigt, dass, vorausgesetzt die Windenergieanlage befindet sich in Parkposition, eine Detektion von schon geringen Schäden an Gründungs-strukturen mit dem beschriebenen Verfahren, auch unter Einsatz weniger Messaufnehmer, zuverlässig möglich ist. T2 - Wissenschaftliche Aussprache CY - Berlin, Germany DA - 19.10.2018 KW - Offshore-Windenergieanlagen KW - Structural Health Monitoring KW - Schwingungsbasierte Verfahren KW - Schadensdetektion KW - Unterraummethoden PY - 2018 AN - OPUS4-47006 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hille, Falk A1 - Makris, Ruben T1 - Risslumineszenz N2 - Präsentation zur Entwicklung einer Spezialbeschichtung zur Detektion und Überwachung von Ermüdungsrissen. T2 - BAST Ausschusssitzung der Bund-/Länderarbeitsgruppe AG 2.5 - Korrosionsschutz für Stahlbauten im Bereich der Bundesfernstraßen CY - Hamburg, Germany DA - 02.03.2018 KW - Risslumineszenz KW - Ermüdungsschäden PY - 2018 AN - OPUS4-47009 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Herrmann, Ralf A1 - Rabe, J. A1 - Marx, S. T1 - Datenmanagement und –analyse von kontinuierlichen Datenströmen bei Offshore Windparks N2 - Mit der Errichtung und der Inbetriebnahme des Windpark alpha ventus wurden umfangreiche Messungen an den Tragstrukturen und den Umgebungsparametern durchgeführt. Im Projekt Gigawind life wurde im TP1 ein Datenmanagementsystem zur kontinuierlichen und periodisch fortgeführten Datenauswertung für große Datenbestände (Big Data) entworfen und realisiert. Anhand von Performanceuntersuchungen konnte eine Verkürzung der Rechenzeit um den Faktor 10 in einem Rechencluster erreicht werden. Unter Anwendung einer Datenpipeline nach dem Publish/Subscribe Prinzip wird eine skalierbare Datenschnittstelle für Monitoringdaten vorgeschlagen. T2 - Messen im Bauwesen CY - Berlin, Germany DA - 13.11.2018 KW - Datenmanagement KW - Big Data KW - Windenergie KW - Monitoring PY - 2018 AN - OPUS4-46916 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Cuéllar, Pablo T1 - Deep foundations for offshore wind turbines T1 - Cimentaciones profundas para aerogeneradores marinos N2 - This presentation deals with the phenomenology and design of pile foundations for offshore wind turbines, and is divided in 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. 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 cyclic pile fatigue and the so-called pile setup (i.e. the time effects on the axial pile capacity). The relevance of these 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 - Madrid, Spain DA - 13.04.2018 KW - Offshore pile foundations KW - Load bearing behaviour KW - Design methods PY - 2018 AN - OPUS4-46311 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Cuéllar, Pablo A1 - Baeßler, Matthias T1 - Mechanical design challenges for offshore wind-farms N2 - This talk provides a brief introduction on general engineering aspects of offshore wind energy production. Some geomechanical issues for the foundation of OWTs into the seabed are introduced, while the results from experimental investigations and coupled computational analysis are discussed. In the second part of the seminar, 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. Concerning the geomechanical issues the talk shows that: i) The pile’s bearing capacity can degrade under cyclic loading (waves, wind, …). ii) The time effects can be relevant: Capacity improvement can be substantial, but also fragile. iii) There are cyclic PWP effects: Cyclic interaction with pore water may lead to soil softening and an uncoupled analysis (current design practice) is potentially unsafe. And concerning the hydromechanical and aerodynamical design considerations, this seminar shows that: i) Numerical analysis of turbine’s interaction with wind/waves is useful and affordable. ii) Simplified models can provide insight into windfarm aerodynamics. iii) Turbulent wake analysis is very relevant for the windfarm layout. T2 - Energy Science Kolloquium, Fakultät für Physik, Universität Duisburg-Essen CY - Duisburg, Germany DA - 11.10.2018 KW - Geomechanics of offshore foundations KW - Wave-Tower interaction KW - Windfarm wake analysis PY - 2018 AN - OPUS4-46313 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Benseghier, Z. A1 - Cuéllar, Pablo A1 - Luu, L.-H. A1 - Delenne, J.-Y. A1 - Bonelli, S. A1 - Philippe, P. T1 - Use of DEM-LBM modeling to prove the relevance of free jet model for soil erosion by impinging jet N2 - The aim of this study is to provide a micromechanical insight into the mechanisms taking place during the erosion of a cohesive granular material driven by a fluid flow, the objectives are summarized as follows: Perform numerical erosion tests. Parallelization of the code (Gpu). Extensive parametric analysis => rely micro parameters (eg. Cohesion) to macro parameters (eg. Soil erodibility, mechanical strengths). T2 - 2nd YADE Workshop, IRSTEA, Aix-en-Provence CY - Aix-en-Provence, France DA - 26.04.2018 KW - DEM-LBM simulation KW - Erosion of cohesive soils KW - Jet erosion test PY - 2018 AN - OPUS4-46315 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Cuéllar, Pablo T1 - Deep foundations for offshore wind turbines T1 - Cimentaciones profundas para aerogeneradores marinos 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. 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 2019 CEDEX-UNED: MECÁNICA DEL SUELO E INGENIERÍA GEOTÉCNICA CY - Laboratorio de Geotecnia, CEDEX, Madrid, Spain DA - 25.03.2019 KW - Pile foundations KW - Offshore wind turbines KW - Physical phenomenology KW - Design methods KW - Numerical modelling KW - Physical testing PY - 2019 AN - OPUS4-47624 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Baeßler, Matthias A1 - Babutzka, Martin A1 - Trappe, Volker A1 - Pittner, Andreas A1 - Krankenhagen, Rainer A1 - Kühne, Hans-Carsten T1 - Vorstellung des Aktivitätsfelds Erneuerbare Energie N2 - Auf der Beiratssitzung des TF Energie wurde das Aktivitätsfeld Erneuerbare Energien in seinem breiten Spektrum (aber selektive Auswahl) vorgestellt. T2 - Beiratssitzung TF Energie CY - BAM Berlin-Adlershof, Germany DA - 09.04.2019 KW - Erneuerbare Energien KW - Windenergie PY - 2019 AN - OPUS4-47751 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz T1 - Vehicle-track-soil interaction and train-induced ground vibration: Theory and measurements in Germany, Switzerland and France N2 - Three measurement campaigns of train-induced ground vibrations are evaluated for the vehicle-track-soil interaction. Ground vibrations, track vibrations and vehicle vibrations have been measured for train passages and impulse excitation and compared with theoretical results. The soil and the track-soil system are calculated by wavenumber integrals. The influence of the vehicle is introduced by a substructure method. By comparing theory and measurement the different components of excitation force and ground vibration can be analysed, the quasi-static excitation, track-alignment errors, the out-of-roundness of wheels, the wheel and rail roughness, and moreover, scattered axle impulses and ineffective high-frequency parts of the wheelset accelerations and Forces. T2 - Recent Advance in Structural Dynamics CY - Lyon, France DA - 15.04.2019 KW - Vehicle-track-soil interaction KW - Train-induced ground vibration PY - 2019 AN - OPUS4-47893 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz T1 - Roughness and wheelset acceleration from axle-box measurements for understanding the generation and mitigation of ground vibrations N2 - Two measurement campaigns of train-induced ground vibrations are evaluated for the vehicle-track-soil interaction. Ground vibrations, track vibrations and vehicle vibrations have been measured for train passages and impulse excitation and compared with theoretical results. The soil and the track-soil system are calculated by wavenumber integrals. The influence of the vehicle is introduced by a substructure method. By comparing theory and measurement the different components of excitation force and ground vibration can be analysed, the quasi-static excitation, track-alignment errors, the out-of-roundness of wheels, the wheel and rail roughness, and moreover, scattered axle impulses and ineffective high-frequency parts of the wheelset accelerations and forces. T2 - ISO/TC 108/SC 2/WG 8 Working group Ground-borne noise and vibration from rail systems CY - Berlin, Germany DA - 12.03.2019 KW - Vehicle-track-soil interaction KW - Train-induced ground vibration PY - 2019 AN - OPUS4-47894 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz T1 - Soil-foundation-structure problems related to train induced vibrations - the kinematic interaction of tunnel excited pile foundations and the inertial interaction of high rise buildings N2 - The soil-foundation-structure interaction is always important when building vibrations due to train passages have to be considered. The frequency range for train vibrations is up to 100 Hz. Normally, soft surface soils are crucial so that the wavelength can be much smaller than the foundation dimensions. Three topics are of interest for the prediction and the under-standing of building vibrations. 1. The „kinematic interaction“ or the „added foundation ef-fect“, which is calculated either by the combined boundary-element finite-element method or by the wavenumber domain method, results in a reduction of the free-field vibration. The stiff-ness of the foundation resists the wave deformation, plates and walls for horizontally propa-gating waves or piles for vertically incident waves. 2. The „inertial interaction“ or the „added building effect“ yields an amplification around the vertical building resonance, which may be a rigid mode on the compliant soil or a flexible mode for high-rise buildings, and a reduction at higher frequencies. This has been analysed by detailed finite element models of apartment and office buildings. 3. Base isolation is a method to further reduce building vibrations. It is important to know the soil-foundation impedance for the possible reduction, as well as the correct building impedance. A high-rise building cannot be considered as a rigid mass model. It has a frequency-dependent behaviour with longitudinal waves travelling from the founda-tion to the top of the building which include the effect of floor vibrations. Experiences from building projects in Vienna, Frankfort and Berlin will give some additional results for the ex-citation from tunnel lines, the kinematic response of pile foundations, and the inertial re-sponse of the flexible multi-storey buildings. T2 - Computational Methods in Structural Dynamics and Earthquake Engineering (COMPDYN 2023) CY - Athens, Greece DA - 12.06.2023 KW - Soil-pile interaction KW - Pile groups KW - Kinematic interaction KW - Inertial interaction KW - High-rise buildings KW - Base isolation PY - 2023 AN - OPUS4-57954 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz T1 - Some resonance effects of non-typical trains and railway bridges investigated by a frequency-domain method N2 - The resonances of railway bridges have often been analysed for short bridges under periodical high-speed trains, for simply supported one-span bridges, for the fundamental bridge mode, and by time-domain analyses. Many time-consuming calculations have been performed to establish simplified rules for standards. In this contribution, the passage of different (existing, new and hypothetic) trains over different bridges will be analysed in frequency domain by using three separated spectra with the purpose to get a better physical insight in the phenomena. At first, the excitation spectrum of the modal forces is built by the mode shape and the passage time of the train over the bridge. The second spectrum is the frequency response function of the bridge which include the modal frequency, damping and mass. The third part is the spectrum of the axle sequence of an arbitrary train which is not limited to periodical or specific (conventional, articulated, regular or standard) trains and which does not include any bridge parameters. The final solution in frequency domain is obtained as the product of these three complex, strongly varying spectra for the dominating bridge mode or in general as the sum of these products over all relevant bridge modes. The time domain solution is obtained via the inverse Fourier transform, and the resulting time histories have been successfully compared with some measurement results. The method is applied to the vertical and torsional modes of a mid-long 1-span bridge on elastomeric bearings under standard train speeds, and to a long multi-span integral bridge under long periodical freight trains. Different resonance and cancellation effects have been found for systematically varied train speeds according to the axle sequence of the whole train which is dominated by the two locomotives in that case. To be more specific, the first torsional mode of the mid-span bridge is excited for a train speed of 100 km/h whereas the second bending mode is excited for a train speed of 160 km/h. In both cases, the other mode is suppressed by the minima of the axle-distance spectra. In addition, the case of the German high-speed train ICE4 and the very high-speed hyperloop case will be discussed briefly. In general, it is shown that resonance effects are also worth to be studied for freight and passenger trains with lower speeds. T2 - EURODYN 2023 XII International Conference on Structural Dynamics CY - Delft, Netherlands DA - 03.07.2023 KW - Railway bridge KW - Transfer fuction KW - Modal load spectrum KW - Axle-sequence spectrum KW - Freight train KW - Passenger train KW - High-speed train KW - 2-span bridge PY - 2023 AN - OPUS4-57955 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 - Simon, Patrick T1 - Zustandsbewertung von Bauwerken unter veränderlichen Umgebungsbedingungen mittels Structural Health Monitoring N2 - Brücken sind Teil der alternden Verkehrsinfrastruktur. Um die Nutzungsdauer zu verlängern und plötzliche Schäden zu detektieren kann Bauwerksmonitoring ("Structural Health Monitoring") eingesetzt werden. Der Einfluss von Umgebungsbedingungen, beispielsweise der Temperatur, auf das Bauwerksverhalten ist meist größer als der Einfluss von Schäden. Diese Einflüsse bestmöglich voneinander zu trennen und Veränderungen im Tragverhalten korrekt Schäden oder Umgebungsbedingungen zuzuordnen ist eine offene Forschungsfrage. Diese Arbeit zeigt eine mögliche Lösung, bei der gekoppelte Modelle von Umwelteinflüssen, Schäden und Tragverhalten des Bauwerks auf Grundlage von Monitoringdaten aktualisiert werden. Das Framework dazu wird vorgestellt und an einem Laborexperiment eines Stahlbetonbalkens in der Klimakammer angewandt. Die Ergebnisse bestätigen die Vorgehensweise. In nächsten Schritten müssen komplexere Tragwerke und die Sensitivität des Ansatzes untersucht werden. T2 - Forschungskolloquium, Institut für Konstruktiven Ingenieurbau, Bauhaus-Universität Weimar CY - Weimar, Germany DA - 28.06.2023 KW - Structural health monitoring KW - Bauwerksmonitoring KW - Umwelteinflüsse KW - Brücken PY - 2023 AN - OPUS4-58005 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Baeßler, Matthias A1 - Herrmann, Ralf A1 - Hille, Falk A1 - Ziegler, Fred A1 - Said, Samir A1 - Wille, Frank A1 - Quercetti, Thomas A1 - Minack, Mathias A1 - Sterthaus, Jens 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 - Auersch, Lutz T1 - Prognoseverfahren für Bahnerschütterungen – DIN 45672-3, VDI 3837, HighSpeed2 und die Fahrzeug-Fahrweg-Boden Wechselwirkung N2 - Die VDI Richtlinie 3837 enthält detaillierte Angaben zur Erschütterungsemission. Die DIN 45672-3 enthält nur den Tunnel- oder einen Bodenmesspunkt als Ausgangspunkt der Prognose. Die Erschütterungsanregung durch die Fahrzeug-Fahrweg-Wechselwirkung wird beschrieben. Die ERgebnisse der BAM stimmen sehr gut mit dem Prognosekonzept von Highspeed 2 überein. Dies wird an den Punkten 1. Störgrößen, 2. Achsimpulse, 3. Tunnelstrecken aufgezeigt. T2 - Norm-Arbeitsausschuss Schwingungsminderung in der Umgebung von Verkehrswegen CY - Frankfurt/M., Germany DA - 08.02.2023 KW - Normung KW - Bahnerschütterungen KW - Emission KW - Fahrzeug-Fahrweg-Boden-Wechselwirkung KW - Störgrößen KW - Achsimpulse KW - Tunnelstrecke PY - 2023 AN - OPUS4-56978 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ratkovac, Mirjana A1 - Baeßler, Matthias T1 - Perspectives on Wind and Wave Load Reconstruction from SHM Data for Offshore Wind Turbines N2 - As many wind turbines approach the end of their design lifetime, from a technical point of view, comprehensive fatigue analysis of all critical parts is necessary to decide what comes after – continued operation, repowering, or decommissioning. Typically, it is a two-stage evaluation process consisting of a physical inspection of the structure and an analytical part to compare the design and actually experienced loading conditions. Structural health monitoring helps to reduce the uncertainties in the estimations by providing insight into deviations between the designed and the built structure. Furthermore, it allows the evaluation of the consumed fatigue lifetime by analyzing the strain measurements that mirror the actual structural response to experienced environmental and operational conditions. However, the measurement values are limited to a sparse number of instrumented spots on the structure, and further extrapolation to the non-instrumented (critical) sections is required to perform a complete fatigue assessment. One known approach is the external force reconstruction, which has only scarcely been considered for application in offshore wind turbines. In order to extend the previously developed thrust force reconstruction framework, this work discusses the possibilities and challenges of wind and wave loading reconstruction in offshore wind turbine support structures. T2 - 4th International Conference on Health Monitoring of Civil & Maritime Structures (HeaMES 2023) CY - Online meeting DA - 12.06.2023 KW - Wind turbines KW - Force reconstruction KW - Structural Health Monitoring PY - 2023 AN - OPUS4-57687 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz T1 - Challenges of vibration prediction – realistic irregularities, the scattering of axle pulses, and the tunnel-surface reduction N2 - A prediction software has been developed by BAM. The following topics have still be solved. A realistic irregularity spectrum can be derived from axle-box measurements. It agrees wel with the spectrum used for the high-speed 2 project in the United Kingdom. In addition, the scattering of axle pulses should be included. This mid-frequency component can also be found in the HS2 procedure. Finally, the reduction in case of a tunnel line compared to a surface line should be included. Some measurement results of BAM, HS2 and other institutes show a certain mid-frequency reduction. This is due to the load distribution of the tunnel which yields softer axle pulses and the scattered axle impulses are reduced. T2 - ISO/TC 108/SC 2/WG 8 Working group Ground-borne noise and vibration from rail systems CY - London, UK DA - 21.11.2022 KW - Ground vibration KW - Railway trafiic KW - Prediction KW - Irregularities KW - Axle pulses KW - Tunnel line KW - Surface line PY - 2022 AN - OPUS4-56738 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 - Auersch, Lutz A1 - Said, Samir 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 - Frequenz- und bodenabhängige Prognose und Minderung von Bahnerschütterungen N2 - Die Prognose und Minderung von Bahnerschütterungen haben eine lange Tradition in der Bundesanstalt für Materialforschung und -prüfung. Im Jahr 2006 wurde eine Prognose-Software fertiggestellt, die viele Forschungs- und Messergebnisse zusammenfasst. Sie umfasst die Teilbereiche Emission (die Anregung durch die Fahrzeug-Fahrweg-Untergrund-Wechselwirkung), die Transmission (die Ausbreitung durch den Boden) und die Immission (die Übertragung vom Freifeld in ein Gebäude). Die Prognose geschieht in allen Teilen mit einfachen Formeln, die veröffentlicht sind und zur Anwendung für Jedermann zur Verfügung stehen. Es werden Beispiele zur Emission und zur Transmission gezeigt. Im Bereich Transmissionsprognose werden zu den Anregungskräften (aus dem Emissionsteil) die Bodenerschütterungen als Schwinggeschwindigkeitsterzspektren berechnet. Das Ergebnis hängt stark von der Bodensteifigkeit, -dämpfung und -schichtung ab. Dies wurde später mit einer Messkampagne in der Schweiz an 10 Messorten bestätigt (Bild 1). Die Berechnung erfolgt näherungsweise für einen geschichteten Boden mit einer frequenzabhängigen Wellengeschwindigkeit (Dispersion) oder einem tiefenabhängigen Wellengeschwindigkeitsprofil. Die Anregungskräfte werden im Prognosebereich Emission mit einem 2-dimensionalen Gleismodell berechnet (Bild 2). 1-dimensionale Modelle liefern meist falsche Ergebnisse und 3-dimensionale Modelle (zum Beispiel mit der kombinierten Finite-Element-Randelement-Methode) sind für eine Erschütterungs¬prognose sicherlich zu aufwändig. Das 2-dimensionale Modell wurde an 3-dimensionale Ergebnisse so angepasst, dass die Ergebnisse für viele Gleise und Böden annähernd zutreffen. Auch Minderungs¬maßnahmen am Gleis können mit diesem Modell sehr gut berechnet werden. Die Prognoseverfahren wurden in den folgenden Jahren weiter verfeinert. Es wurde die quasi-statische Anregung durch die bewegten statischen Zuglasten mit einer Näherungsformel ergänzt, so dass auch das tieffrequente Nahfeld realistisch erfasst werden kann. Mit der Berücksichtigung der Achsfolge (insbesondere zwischen den Achsen im Drehgestell) ergeben sich zwei typische Minima in den Erschütterungsspektren, die oft auch in den Messungen beobachtet werden. Der Amplitudenanteil zwischen diesen beiden Minima ist oft stärker angehoben, so dass hier eine zusätzliche Erschütterungsanregung vermutet wird. Dieser Anteil kann rein empirisch prognostiziert werden, so wie das in den englischen Prognosen (zuletzt für das Highspeed2-Projekt) enthalten ist. Die Begründung dieses Anteils ist allerdings nicht die Achsfolge, sondern die Zerstreuung der statischen Achslastimpulse durch einen unregelmäßigen Gleisuntergrund und Boden. Die messtechnische Ermittlung eines Minderungseffektes ist komplizierter als allgemein angenommen. Es reicht nicht aus, jeweils an einem Messpunkt in der Nähe eines Gleises mit und ohne Minderungs¬maßnahme die Erschütterungen zu messen und aus dem Verhältnis der Amplituden (beziehungsweise aus der Differenz der Pegel) „die Einfügedämmung“ zu ermitteln. Es wird an Beispielen gezeigt, wie man hier sinnvoller vorgehen kann. 1. Zunächst ist es wichtig, nicht nur die Einfügedämmung sondern auch die Originalspektren mit und ohne Minderung zu dokumentieren und zu veröffentlichen, damit man kontrollieren kann, ob wesentliche Amplituden und Frequenzbereiche reduziert sind oder ob es sich um eher zufällige Minderungen oder Verstärkungen handelt. (Beispiel Unterschottermatte/Raron, Müller/SBB) 2. Der Messpunkt sollte nicht im Nahbereich des Gleises liegen, da ansonsten eine zu günstige, falsche Einfügedämmung bestimmt wird. (Beispiel Tunnel/ Leipzig/Breitsamter) 3. Um Zufälligkeiten zu vermeiden, sollte man an mehr als einem Punkt messen. (Beispiel Unterschotterplatte/Altheim/Auersch) 4. Man sollte eigentlich immer auch die Bodenkennwerte (Steifigkeit, Dämpfung, Amplituden-abnahme, Übertagungsfunktion) messen. Selbst bei nahegelegene Messquerschnitten kann man Überraschungen erleben. (Beispiel erste ICE-Messungen/bei Würzburg/Auersch) 5. Bei verschiedenen Bodenkennwerten kann man eine Korrektur durchführen. (Beispiel Gleis-tröge/Mistler) Am besten bestimmt man ein äquivalentes Kraftspektrum zu jedem Messort und jedem Messzug (Beispiel Feste Fahrbahn/Gardelegen/Auersch) 6. Prinzipiell gibt es nicht die Einfügedämmung einer Maßnahme. Die Einfügedämmung ist immer boden- und referenzsystemabhängig. Die „beste“ Einfügungsdämmung erhält man mit einem steifen Untergrund (Beispiel Unterschottermatte/Tunnel/München Gasteig/Wettschureck) Das heißt aber nicht, dass die Maßnahme durch einen künstlich versteiften Untergrund besser wird (Beispiel Unterschottermatten/RRT2006/Auersch) Es werden Messbeispiele gezeigt, die alle neben einer hochfrequenten dynamischen Minderung auch eine mittelfrequente quasi-statische Minderung aufweisen. Dabei wird der mittelfrequente Zerstreuanteil der statischen Achslastimpulse durch die breitere Lastverteilung und damit die Impulsdehnung der Achslastimpulse reduziert. Diese Impulsdehnung lässt sich mit dem 2-dimensionalen Gleismodell berechnen. Die Minderungswirkung hängt aber wiederum vom Referenzsystem und dessen unregel¬mäßiger Steifigkeitsverteilung ab. Je unregelmäßiger der Boden und Gleisuntergrund des Referenz¬systems, desto stärker ist die Minderungswirkung. T2 - 24. Symposium für Baudynamik und Erschütterungsmessungen CY - Dübendorf, Switzerland DA - 09.06.2023 KW - Bahnerschütterungen KW - Erschütterungsprognose KW - Erschütterungsminderung KW - Elastische Gleiselemente KW - Gleiströge KW - zerstreute Achslastimpulse PY - 2023 AN - OPUS4-57952 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schepers, Winfried A1 - Kulke, Dennis T1 - Korrelationen zwischen Sondierungen und dynamischen Bodeneigenschaften N2 - Wir zeigen, dass bei homogenen ausgeprägt sandartigen Böden mit statistisch ermittelten Korrelationen die dynamischen Bodensteifigkeiten mit einer Genauigkeit abgeschätzt werden können, die mit der Ungenauigkeit der seismischen Verfahren übereinstimmt. Mit zunehmenden Feinkornanteil werden die Unsicherheiten der statistischen Korrelationen größer. Bei stark überkonsolidierten glazialen Böden sollte von der Anwendung empirischer Korrelationen Abstand genommen werden. T2 - 18. D-A-CH-Tagung für Erdbebeningenieurwesen und Baudynamik CY - Kiel, Germany DA - 14.09.2023 KW - Baugrunddynamik KW - Dynamische Bodenkennwerte KW - Statistische Korrelationen PY - 2023 AN - OPUS4-58581 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schepers, Winfried A1 - Brinkgreve, Ronald A1 - Appel, Silke T1 - Cone penetration tests and dynamic soil properties N2 - Current standards like ISO 14837-32:2015 and DIN EN 1998-1/NA:2021 as well as prEN 1997-2:2022 allow for using correlations between the results of in-situ soil penetration tests and shear wave velocity (or shear modulus) to determine soil properties to be used in dynamic analyses. While the ISO and prEN standards even provide some recommendations on specific correlations to be used, the DIN standard does not. Due to the statistical nature of such correlations their general applicability has to be verified. We collected data sets from test sites from Germany as well as New Zealand at which cone penetration tests (CPT) as well as seismic site investigation methods were conducted. These sites comprise sandy soils as well as clayey soils, mixed soils as well as glacial soils. We compare the results of several correlations between CPT results and shear wave velocity. The accuracy of such correlations is assessed with respect to the accuracy of seismic in-situ tests. It turns out that for clean sands such correlations between CPT and Vs have a similar order of variability as seismic in-situ tests conducted at the same site. The higher the fines portion of the soil, the higher the variability of the statistical correlations, and consequently the less the general applicability. For glacial soils and other special soil types usage of statistical correlations to determine dynamic soil properties is not recommended. T2 - Eurodyn 2023 CY - Delft, Netherlands DA - 02.07.2023 KW - Dynamic soil properties KW - Statistical correlations PY - 2023 AN - OPUS4-58582 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schepers, Winfried A1 - Brinkgreve, Ronald A1 - Appel, Silke T1 - Recommendations on finite Element modelling of non-seismic excitation in soil-structure interaction problems N2 - Nowadays geotechnical engineering firms have powerful software tools to extent their consulting business also into dynamic soil-structure interaction, which before has been restricted to a rather small community of specialized experts in this field, and they certainly do. This is particularly true with respect to non-seismic sources, that is all kinds of human induced vibrations. Hence, there is a demand from clients as well as from contractors to have guidance on the requirements as well as the limits of numerical modelling of soil-structure interaction. From the literature as well as from relevant standards, recommendations for the numerical modelling of soil-structure interaction problems involving seismic actions are well known, e. g. ASCE/SEI 4-16. There are, however, some particularities when dealing with human-induced vibrations, which are absent in seismic analyses. For human-induced excitations very little specific guidance has been published in the past. A machine foundation on a homogeneous half space excited by harmonic loads with excitation frequency between 4 Hz and 64 Hz has been analysed by means of several commercially available software packages. Parametric studies have been performed to verify if recommendations for seismic soil-structure analyses are valid for non-seismic analyses as well. This paper provides details on the benchmark example and the most important conclusions from the undertaken parametric studies. T2 - Eurodyn 2023 CY - Delft, Netherlands DA - 02.07.2023 KW - Numerical analysis KW - Vibrations KW - Soil-structure interaction PY - 2023 AN - OPUS4-58583 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 - 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 -