TY - CONF A1 - Auersch, Lutz A1 - Said, Samir A1 - Rohrmann, R. T1 - Natural frequencies and modes of poles, beams, floors, road and rail bridges T2 - Proc. of ISMA/USD 2020 N2 - In the last three decades, the vibrations of many floors and bridges have been measured. The contribution shows some evaluation methods, experimental results and some modelling and theoretical results. Simple evaluation methods have been developed for single and coupled floors. Two coupled beams have been measured in good agreement with the theory. A more complex coupling model has been found for a large wooden floor in a castle consisting of six floor bays which correlates well with the measurements. Damaged and intact poles have been tested by their natural frequencies and damping values, and a fair correlation between the degree of damage and the shift of the frequency. Road bridges have been analysed in detail and some examples are presented. Railway bridges and trains are studied for resonant excitation. The risk of resonance can be estimated in frequency domain by using axle-sequence spectra of the train and the natural frequencies of the bridge. A measurement example shows the amplification, but even stronger the cancellation of the subsequent axle responses. Several high-speed trains and freight trains have been analysed for their potential resonance amplification. T2 - International Conference on Noise and Vibration Engineering (ISMA/USD 2020) CY - Online meeting DA - 07.09.2020 KW - Modalanalyse KW - Bauwerke KW - Bauteile KW - Brücken KW - Achsfolgespektren PY - 2020 SP - 1573 EP - 1585 PB - KULeuven CY - Leuven AN - OPUS4-51211 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz ED - Lombaert, G. ED - Degrande, G. T1 - Predicted and measured amplitude-speed relations of railway ground vibrations at four German sites with different test trains T2 - Proc. of the 13th International Workshop on Railway Noise and Vibration N2 - The present contribution evaluates four measuring series made by the Federal Institute of Material Research and Testing for the relations between train speed and ground vibration amplitudes. This experimental evaluation is supported by the simulation of the train passages at the different sites by using appropriate excitation mechanisms and forces as well as layered soil models which have been derived from impact measurements at each site. T2 - 13th International Workshop on Railway Noise and Vibration CY - Leuven, Belgium DA - 16.09.2019 KW - Train speed KW - Ground vibration KW - Excitation forces KW - Layered soils PY - 2019 SP - 1 EP - 8 PB - KU Leuven CY - Leuven AN - OPUS4-49440 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz T1 - Prediction of building noise and vibration – 3D finite element and 1D wave propagation models T2 - Proceedings of Euronoise 2021 N2 - Construction work or traffic excite nearby buildings, and the perceptible or audible vibration can be a nuisance for the inhabitants. The transfer of the vibration from the free field to the building has been calculated by the finite element method for many models in consultancy and research work. The analysis for all storeys of certain building points such as walls, columns and floors unveiled some rules, some typical modes, and some wavetype responses. A simplified building-soil model has been created, which includes well these effects of building-soil resonance, wall/column resonance, floor resonances, and the high-frequency reduction. The model consists of one wall for a wall-type apartment building or a column for each specific part (mid, side or corner) of a column-type office building. The building response in the high-frequency (acoustic) region is calculated as mean values over all storeys and over wider frequency bands, by wave-type asymptotes of an infinitely tall building, and by the soil to wall ratio of impedances. The secondary noise is predicted by Transfer values between the building vibration (center of floors, walls at a room corner) and the sound pressure. T2 - Euronoise 2021 CY - Online meeting DA - 25.10.2021 KW - Building vibration KW - Finite element models KW - Soil-wall-floor model KW - Apartment building KW - Office tower PY - 2021 SN - 978-989-53387-0-2 SP - 1792 EP - 1801 AN - OPUS4-53702 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Said, Samir A1 - Auersch, Lutz T1 - Prediction of explosion-induced ground and building vibrations - measured wave velocities, transfer functions and attenuation T2 - Proceedings of the 25th International Congress on Sound and Vibration, Sound of Peace Bell, 2018 N2 - Explosion-induced ground vibrations have been measured at several places. Results about the wave propagation are shown in this contribution. The particle velocities of the soil have been measured at up to 1000 m distance from the explosion and are presented as time records (seismograms) and one-third octave band spectra (transfer functions). The results are compared with the results of hammer impacts. The seismograms clearly show different wave types, compressional waves of the air, the water and the soil, and the Rayleigh wave. The hammer impacts yield good results up to 100 m and incorporate higher frequencies at about 50 Hz, whereas the explosion results in a ground vibration with frequencies around 10 Hz and a longer range of influence. Explosion and hammer excitations are evaluated for the wave velocities of the soil by using the wavenumber and the spatial auto-correlation method. The attenuation of the ground vibration amplitudes A with distance r can well be presented by a power law A ~ r -q. This type of amplitude-distance law and the corresponding power q > 1 are substantiated in the contribution. The influence of the charge weight W is evaluated as an additional power law A ~ W -p for each measuring site. The power is found quite similarly around q  0.6 as all sites have a medium soft soil such as sand and clay. The obtained amplitude-charge-distance law can be used to predict the explosion-induced ground and building vibrations at other sites. T2 - International Congress on Sound and Vibration (ICSV25) CY - Hiroshima, Japan DA - 08.07.2018 KW - Prediction of explosion induced ground and building vibration KW - Explosion-induced ground vibrations KW - Hammer impact KW - Soil properties KW - Amplitude-distance laws KW - Amplitude-charge weight laws PY - 2018 SN - 978-83-7880-552-6 SN - 2329-3675 SP - 1 EP - 8 PB - Silesian University of Technology Press CY - Gliwice, Poland AN - OPUS4-45506 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz T1 - Railway-induced ground and building vibrations – Analysis in frequency-wavenumber domain and fast prediction with approximate models T2 - Proceedings of the ISMA Conference 2022 N2 - A simple and fast prediction scheme is presented for train-induced ground and building vibrations. For the emission, finite-element boundary-element or multiple-beam-on-continuous-soil models of the track have been analysed and approximated by faster track-on-Winkler-soil models. The vehicle-track interaction due to irregularities yields the excitation forces. For the transmission of waves in the soil, the wavenumber integral of the compliance of layered soils has been evaluated. The calculation time is reduced for the prediction by using the solution of a homogeneous half-space with a frequency-dependent wave velocity (the dispersion) of the soil. For the immision, many 2 and 3-dimenisonal finite-element building models have been investigated, and a good approximation has been established by a 1-dimensional soil-wall-floor model. In addition, the axle sequence of the train, the quasi-static and the “scattered” response of the soil, and the wave propagation from a tunnel to a pile foundation of a building have been included. T2 - ISMA-Conference 2022 CY - Leuven, Belgium DA - 12.09.2022 KW - Ground vibration KW - Simple prediction KW - Vehicle-track interaction KW - Layered soil KW - Soil-building interaction KW - Soil-wall-floor model KW - Propagation from a tunnel KW - Tunnel-pile transfer PY - 2022 SP - 1 EP - 13 PB - KU Leuven CY - Leuven AN - OPUS4-56603 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz T1 - Realistic axle-load spectra for the prediction of ground vibrations form rail traffic T2 - ICSV22 - 22nd International congress on sound and vibration (Proceedings) N2 - Train passages induce static and dynamic forces on the track, the train-induced vibrations propagate through the soil and excite neighbouring buildings. The problem of train vibrations is divided into the parts emission, which is the excitation by railway traffic (the present contribution), transmission, which is the wave propagation through the soil, and immission, which is the transfer into a building, - The calculation of the axle loads are based on the vehicle-track-soil interaction. This interaction uses the dynamic stiffness of the vehicle (the inertia of the wheelset) and the dynamic stiffness of the track-soil System. Based on various time consuming finite-element boundary-element calculations, an approximate track-soil model has been established. The vehicle-track-soil analysis yields several transfer functions between the various geometric or stiffness irregularities and the axle loads of the train. Geometric irregularities of the vehicle (the wheels) and the track (rail surface and track alignment) are the simplest components. Geometric irregularities of the subsoil (trackbed irregularities) have to be transferred to effective irregularities at rail level. The bending stiffness of the track is filtering out the short-wavelength contribution. Stiffness irregularities occur due to random variations in the bailast or the subsoil, which must also be transferred to effective track irregularities, and due to the discrete rail support on sleepers. The axle loads due to the effective track errors from stiffness variations have their specific vehicle-track transfer function. - All necessary formula for the prediction of axle-load spectra will be presented. The prediction method is compared with axle-box measurements at a Standard ballasted track. Moreover, ground Vibration measurements at numerous sites are exploited for the axle-load spectra and the Validation of the prediction method. T2 - ICSV22 - 22nd International congress on sound and vibration CY - Florence, Italy DA - 12.07.2015 PY - 2015 SN - 978-88-88942-48-3 SN - 2329-3675 SP - 1 EP - 8 AN - OPUS4-33781 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz ED - Náprstek, J. ED - Horácek, J. ED - Okrouhlík, M. ED - Marvalová, B. ED - Verhulst, F. ED - Sawicki, J.T. T1 - Reducing ground-borne micro-vibrations by plate foundations T2 - Vibration problems ICOVP 2011 - 10th international conference on vibration problems (Proceedings) T2 - Vibration problems ICOVP 2011 - 10th international conference on vibration problems CY - Prague, Czech Republic DA - 2011-09-05 KW - Plate-soil interaction KW - Wave excitation KW - Vibration reduction KW - Finite-element boundary-element method PY - 2011 SN - 978-94-007-2068-8 SN - 0930-8989 N1 - Serientitel: Springer proceedings in physics – Series title: Springer proceedings in physics VL - 139 SP - 329 EP - 335 PB - Springer AN - OPUS4-24804 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz ED - M. Papadrakakis, ED - D.C. Charmpis, ED - N.D. Lagaros, ED - Tsompanakis, Y. T1 - Simple and advanced boundary-element method for the soil and its application to railway dynamics T2 - COMPDYN 2007 - Computational methods in structural dynamics and earthquake engineering (Proceedings) T2 - COMPDYN 2007 CY - Rethymno, Crete, Greece DA - 2007-06-13 KW - Finite-element boundary-element method KW - Explicit Green´s functions KW - Track vibration KW - Tunnel vibration KW - Vehicle-track-soil interaction KW - Radiation damping PY - 2007 SP - 1 EP - 12 CY - Athen AN - OPUS4-15015 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz A1 - Said, Samir T1 - Simple modal analysis and wave propagation for practical floor experiments in new and old office and residential buildings T2 - EVACES'07 - Experimental vibration analysis for civil engineering structures (Proceedings) T2 - EVACES'07 - Experimental vibration analysis for civil engineering structures CY - Porto, Portugal DA - 2007-10-24 PY - 2007 SN - 978-972-752-095-4 SP - 423 EP - 432 AN - OPUS4-18409 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 T2 - Computational Methods in Structural Dynamics and Earthquake Engineering, Proceedings of COMPDYN 2023 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 - COMPDYN 2023 CY - Athen, Greece DA - 12.06.2023 KW - Kinematic Interaction KW - Inertial Interaction KW - Surface Foundation KW - Pile Foundation KW - High-Rise Building PY - 2023 SP - 1 EP - 14 PB - NTUA CY - Athens AN - OPUS4-57959 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 T2 - Proceedings of the XII International Conference on Structural Dynamics 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 - XII International Conference on Structural Dynamics CY - Delft, The Netherlands DA - 03.07.2023 KW - Railway bridge KW - Transfer function KW - Modal force spectrum KW - Axle-sequence spectrum KW - Freight train KW - Passenger train KW - High-speed train KW - 2-span bridge KW - Long-span bridge PY - 2023 SP - 1 EP - 10 PB - TU Delft CY - Delft AN - OPUS4-57961 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz A1 - Markfort, Greta T1 - Static and dynamic behaviour of pile foundations in homogeneous and inhomogeneous soils T2 - Computational Methods in Structural Dynamics and Earthquake Engineering N2 - Offshore wind energy towers are dynamically loaded by waves and wind. Pile foundations provide stiffness and damping and should be properly calculated. A combined finite-element boundary-element method for the dynamic interaction of flexible structures and the soil has been developed. The flexible structures such as single piles or complete wind energy towers are modeled by the finite element method whereas the homogeneous or layered soil is modeled by the boundary element method which uses the Green’s functions for interior loads in the layered half-space to establish the dynamic stiffness matrix of the soil. Soils with a stiffness that is continuously increasing with depth can be modeled as multi-layer soils with step-wise increasing stiffness. The effects of different parameters such as the stiffness of the soil, the axial and bending stiffness of the pile, and the radius of the cylindrical contact area will be analysed for the different components of excitation (vertical, horizontal, rotation and coupling). The results can be determined as specific power laws which are different for the different load cases and for the different soil models (Winkler support, homogeneous continuum, continuum with increasing stiffness). The dynamic effect of radiation damping will be analysed by the frequency-dependent compliance functions. A clear layering of the soil can cause noticeable changes in the dynamic compliances as reductions of the stiffness and the damping in certain frequency ranges (below and around layer resonance frequencies). The distribution of the displacements along the pile help to explain the observed laws. An example of an offshore wind energy tower has been modeled and calculated for wind, wave and weight loads. The resonances of the tower are usually limited by the radiation damping which is strongest for a soft soil. T2 - COMPDYN 2017 CY - Rhodes, Greece DA - 15.06.2017 KW - Pile foundation KW - Finite-element boundary-element method KW - Pile bending stiffness KW - Soil stiffness KW - Continuously inhomogeneous soils KW - Layered soils KW - Wind energy tower PY - 2017 SP - 4675 EP - 4690 PB - NTUA CY - Athens AN - OPUS4-42089 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz T1 - Structural dynamics and soil-structure-interaction induced by railway traffic T2 - Dynamics of Structures '89 T2 - Dynamics of Structures '89 CY - Karlovy Vary, Czech Republic DA - 1989-09-12 PY - 1989 SP - 21 EP - 25 AN - OPUS4-11554 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz A1 - Said, Samir A1 - Knothe, Esther A1 - Rücker, Werner ED - Cunha, A. ED - Caetano, E. ED - Ribeiro, P. ED - Müller, G. T1 - The dynamic behavior of railway tracks with under sleeper pads, finite-element boundary-element model calculations, laboratory tests and field measurements T2 - EURODYN 2014 - 9th International conference on structural dynamics (Proceedings) N2 - A variety of isolation measures exists to reduce the vibration in the neighbourhood of railway lines. They can be roughly classified as elastic or stiffening systems. There are the following elastic elements, rail pads or resilient fixation systems between rail and sleeper, under sleeper pads or sleeper shoes under the sleepers, and ballast mats under the ballast. Stiffening systems (plates) are used as slab tracks, floating slab tracks, or mass-spring systems. In the EU project “Railway induced vibration abatement solutions (RIVAS)”, elastic under sleeper pads have been investigated. The dynamic behaviour of the track and the surrounding soil has been calculated by the combined finite-element boundary-element method in a systematic parameter study. It has been shown that the mitigation effect can be improved by soft under sleeper pads or by heavy sleepers. Consequently, such track elements (soft under sleeper pads and heavy sleepers) have been thoroughly investigated in laboratory tests to establish the static and dynamic parameters as well as their serviceability. Finally, field tests at and near railway tracks with and without under sleeper pads have been performed. To determine the reduction effect of the isolated track, the ground vibrations excited by trains or artificial sources have been measured. The soil properties at the different sites have also been measured so that the comparison of the isolated and un-isolated track can take into account possible differences of the soil parameters. The contribution shows how the different (numerical, laboratory and field) methods and results can be combined to achieve an improved mitigation solution with soft under sleeper pads and heavy sleepers for ballasted and slab tracks. T2 - EURODYN 2014 - 9th International conference on structural dynamics CY - Porto, Portugal DA - 30.06.2014 KW - Railway track KW - Track-soil interaction KW - Mitigation KW - Under sleeper pads KW - Laboratory tests KW - Field tests KW - Ground vibration PY - 2014 SN - 978-972-752-165-4 SN - 2311-9020 SP - 805 EP - 812 AN - OPUS4-31164 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz ED - De Roeck, G. ED - Degrande, G. ED - Lombaert, G. ED - Müller, G. T1 - The dynamic force transfer of slab tracks and floating slab tracks and the corresponding ground vibration T2 - EURODYN 2011 - 8th International conference on structural dynamics (Proceedings) T2 - EURODYN 2011 - 8th International conference on structural dynamics CY - Leuven, Belgium DA - 2011-07-04 KW - Railway track KW - Slab track KW - Floating slab track KW - Track-soil interaction KW - Force transfer KW - Ground vibration PY - 2011 SN - 978-90-760-1931-4 SP - 820 EP - 827 AN - OPUS4-24556 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz A1 - Said, Samir ED - Gao, G. T1 - The influence of soil properties on the ground vibration due to railway traffic and other sources - the comparability of different sites T2 - 6th International symposium on environmental vibration: Prediction, monitoring, mitigation and evaluation - Advances in environmental vibration (Proceedings) T2 - 6th International symposium on environmental vibration: Prediction, monitoring, mitigation and evaluation - Advances in environmental vibration CY - Shanghai, China DA - 2013-11-08 KW - Soil properties KW - Railway track KW - Ground vibration KW - Measurement KW - Assessment KW - Mitigation PY - 2013 SN - 978-7-5608-5303-1 SP - 175 EP - 186 PB - Tongji University Press AN - OPUS4-29731 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz T1 - The influence of the soil on track dynamics and ground-borne vibration T2 - Proceedings of the 9th International Workshop on Railway Noise (IWRN) T2 - 9th International Workshop on Railway Noise (IWRN) CY - Munich, Germany DA - 2007-09-04 PY - 2007 SP - S.4.1, 1 EP - 9 PB - International Workshop on Railway Noise CY - München AN - OPUS4-16438 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 T2 - EURODYN 2020 Proceedings of the XI International Conference on Structural Dynamics 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 - 13.11.2020 KW - Building vibration KW - Office building KW - Residential building KW - Soil-building resonance KW - Floor resonance KW - Column/wall resonance PY - 2020 SN - 978-618-85072-2-7 SP - 4560 EP - 4576 CY - Athen AN - OPUS4-51678 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz T1 - Tracks with under-ballast plates and their mitigation of train induced ground vibration T2 - Proceedings of the 24th International Congress on Sound and Vibration N2 - Experiments have been performed at a test site with six different tracks with under-ballast plates. Hammer excitations of the soil and the tracks as well as train passages have been measured. The experimental observations are as follows. 1. The natural soil is stiff gravel whereas the railway dam consists of softer material. 2. The track compliance indicates a soft ballast if no train is present to provide a confining pressure. 3. The track response to the train passages can be split into a low-frequency region which is ruled by the static loads and a high-frequency region which is ruled by dynamic loads. 4. The track responses to hammer and track excitation indicate the presence of many voids between the sleepers and the ballast. 5. The ground vibrations are highly influenced by the soil. Due to the stiff soil at the site, the hammer and train induced spectra have a considerable high-frequency content. 6. A reduction of the ground vibration has been observed in a low-frequency range. The mitigation effects of an under-ballast plate are also investigated by calculations of a wavenumber domain model. The under-ballast plate has an effect at low frequencies where it distributes the static load over a longer track section. The impulse of the axle passage is longer and the frequencies are lower due to the plate stiffness. The axle impulses could yield a low-frequency ground vibration in an irregular soil with a randomly varying stiffness. This low-frequency part of the ground vibration (the scattered axle impulses) seem to be reduced by the under-ballast plate. T2 - 24th International Congress on Sound and Vibration CY - London, UK DA - 23.7.2017 KW - Railway vibration KW - Ballast tracks KW - Under-ballast plate KW - Ground vibration PY - 2017 SP - 1 EP - 8 PB - IIAV CY - Auburn, USA AN - OPUS4-42091 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz T1 - Train induced vibration of inhomogeneous soils - a prediction based on measured and calculated point-load solutions T2 - ICSV19 - 19th International congress on sound and vibration (Proceedings) N2 - Vehicle, track and ground vibration as well as their interaction are considered in a combined finite-element boundary-element (FEBEM) approach. The layered soil is calculated in frequency wavenumber domain and the solution for fixed or moving point or track loads follow as wavenumber integrals. The soil results from the measurements and the detailed models are approximated by simple formula which are used for the prediction of train-induced ground vibration. The influence of the track and the soil on the train induced ground vibration is analysed by the detailed models. The ground vibrations strongly depend on the regular and random inhomogeneity of the soil. The regular layering of the soil yields a cut-on and resonance phenomenon while the random inhomogeneity yields a scattering of the axle impulses which proved to be important for high-speed trains. The attenuation with distance of the ground vibration due to the point-like excitations such as vibrator or hammer excitations and the train-track excitation are investigated and compared. All theoretical results are compared with measurements at conventional and high-speed railway lines. T2 - ICSV19 - 19th International congress on sound and vibration CY - Vilnius, Lithuania DA - 08.07.2012 PY - 2012 SN - 978-609-459-079-5 SP - 1 EP - 8 AN - OPUS4-27218 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -