Dokument-ID Dokumenttyp Autoren/innen Persönliche Herausgeber/innen Haupttitel Abstract Auflage Verlagsort Verlag Herausgeber (Institution) Erscheinungsjahr Titel des übergeordneten Werkes Jahrgang/Band ISBN Veranstaltung Veranstaltungsort Beginndatum der Veranstaltung Enddatum der Veranstaltung Ausgabe/Heft Erste Seite Letzte Seite URN DOI Lizenz Datum der Freischaltung OPUS4-27983 Zeitschriftenartikel Auersch, Lutz Response to harmonic wave excitation of finite or infinite elastic plates on a homogeneous or layered half-space The soil–structure interaction of elastic plates on homogeneous or layered soils excited by horizontally propagating waves is analysed. Large plates are modelled by a combined finite-element boundary-element method (FEBEM), whereas the response of infinitely long plates is calculated by a numerical integration in the frequency–wavenumber domain. The finite-element boundary-element method yields the complete soil–plate transfer function of frequency and distance whereas the frequency–wavenumber solution of the infinitely long plate can serve as an approximation for long distances on a finitely long plate. The soil–plate transfer function starts to decrease strongly at the coincidence frequency, where the bending stiffness equals the plate inertia. A strong decrease follows at mid frequencies and a strong reduction of less than 0.1 of the ground vibration is reached at high frequencies. Rules for the characteristic frequencies are derived from the numerical results clearly indicating the strongest influence of the soil stiffness and the weaker influence of the bending stiffness of the plate. The influence of the mass, length and width of the plate are shown to be limited in case of realistic parameters, but it should be noted that the reduction effects are less effective for layered soils and for nearer observation points. Barking Elsevier Appl. Sci. Publ. 2013 Computers and geotechnics 51 50 59 10.1016/j.compgeo.2013.02.001 2016-02-20 OPUS4-39080 Zeitschriftenartikel Auersch, Lutz Static and dynamic behaviours of isolated and unisolated ballast tracks using a fast wavenumber domain method The dynamics of un-isolated and isolated ballast tracks have been analysed by multi-beam models for the track and by a layered half-space model for the soil. The solution is calculated in frequency-wavenumber domain and transformed back to space domain by a wavenumber integral. This is a faster method compared to other detailed track-soil interaction methods and almost as fast as the widely used Winkler-soil method, especially if the compliances of the soil have been stored for repeated use. Frequency-dependent compliances and force transfer functions have been calculated for a variety of track and soil parameters. The ballast has a clear influence on the high-frequency behaviour whereas the soil is dominating the low-frequency behaviour of the track. A layering of the soil may cause a moderate track-soil resonance whereas more pronounced vehicle-track resonances occur with elastic track elements like rail pads, sleeper pads and ballast mats. Above these resonant frequencies, a reduction of the excitation forces follows as a consequence. The track deformation along the track has been analysed for the most interesting track systems. The track deformation is strongly influenced by the resonances due to layering or elastic elements. The attenuation of amplitudes and the velocity of the track-soil waves change considerably around the resonant frequencies. The track deformation due to complete trains have been calculated for different continuous and Winkler soils and compared with the measurement of a train passage showing a good agreement for the continuous soil and clear deviations for the Winkler soil model. Berlin, Heidelberg Springer 2017 Archive of Applied Mechanics 87 3 555 574 10.1007/s00419-016-1209-6 2017-02-06 OPUS4-51334 Zeitschriftenartikel Auersch, Lutz Simple and fast prediction of train-induced track forces, ground and building vibrations A simple and fast prediction scheme is presented for train induced ground and building vibrations. Simple models such as (1-dimensional) transfer matrices are used for the vehicle-track-soil interaction and for the building-soil interaction. The wave propagation through layered soils is approximated by a frequency-dependent homogeneous half-space. The prediction is divided into the parts "emission" (excitation by railway traffic), "transmission" (wave propagation through the soil) and "immission" (transfer into a building). The link between the modules is made by the excitation force between emission and transmission, and by the free-field vibration between transmission and immission. All formula for the simple vehicle-track, soil and building models are given in this article. The behaviour of the models is demonstrated by typical examples, that is the mitigation of train vibrations by elastic track elements, the low- and high-frequency cut-offs characteristic for layered soils, and the interacting soil, wall and floor resonances of multi-storey buildings. It is shown that the results of the simple prediction models can well represent the behaviour of the more time-consuming detailed models, the finite-element boundary-element models of the track, the wavenumber integrals for the soil, and the three-dimensional finite-element models of the building. In addition, measurement examples are given for each part of the prediction confirming that the methods provide reasonable results. As the prediction models are fast in calculation, many predictions can be done, for example to assess the environmental effect along a new railway line. The simple models have the additional advantage that the user needs to know only a minimum of parameters. So, the prediction is fast and user-friendly, but also theoretically and experimentally well-founded. Springer 2020 Railway Engineering Science 28 3 232 250 urn:nbn:de:kobv:b43-513340 10.1007/s40534-020-00218-7 https://creativecommons.org/licenses/by/4.0/deed.de 2020-09-30 OPUS4-31162 Zeitschriftenartikel Auersch, Lutz Train induced ground vibrations: different amplitude-speed relations for two layered soils Ground vibrations created by running high-speed trains at speeds between 100 and 320 km/h are calculated in detail using transfer functions to model the effects of the moving loads. These transfer functions for layered soils are obtained by integration in the wavenumber domain. The train-induced vibrations in a soil that is considered to consist of single layers of two slightly different soils are analysed for different excitations: for their spectra, attenuation laws and amplitude-speed relations. An important mid-frequency component is shifted through the cut-on region of the layered soil with an increase in the train speed. The cut-on frequency divides the response of the layered soil into a low-frequency low-amplitude range and a high-frequency high-amplitude range. This leads to completely different train speed dependencies for the two soil layers with strongly increasing amplitudes around the cut-on frequency and almost constant amplitudes beyond this frequency. All calculated results closely agree with ground vibration measurements at two corresponding sites, especially if the mid-frequency component is calculated by axle impulses. London Sage Publ. 2012 Journal of rail and rapid transit - Proceedings of the Institution of Mechanical Engineers / Part F 226 5 469 488 10.1177/0954409712437305 2016-02-20 OPUS4-58502 Zeitschriftenartikel Auersch, Lutz Site-specific amplitude-distance laws, wave velocities, damping, and transfer functions of the soil from hammer impacts and application to railway-induced ground vibration - Similarities and mid-frequency differences The propagation of ground vibrations is theoretically analysed with frequency-wavenumber and simplified methods. Experimental methods are presented which can characterise the site-specific ground vibrations by wave velocities, stiffness and damping. Measurements with hammer and train excitation have been performed at several sites. The one-third octave spectra show the stiffness-dependent amplitudes and the low- and high-frequency filter effects due to the layering and the damping of the soil. Specific train effects, an additional high-frequency filter, the sleeper passage frequency, and an amplified mid-frequency component can be clearly found. The attenuation with distance is analysed in detail where the theoretical exponential and the empirical frequency-dependent power law are considered. Hammer and train excitation show the same site-specific effects which are mainly due to the stronger or weaker damping of the soil. The train attenuation is generally weaker than the hammer attenuation. The attenuation exponent of the power law, which is strongly dependent on the site and the frequency, is reduced for the train vibration by 0.3 to 0.5 in agreement with the theory. Reasons are discussed for the overall power law and for the dominating mid-frequency component. Springer 2023 Journal of Vibration Engineering & Technologies 1 17 urn:nbn:de:kobv:b43-585020 10.1007/s42417-023-01095-0 https://creativecommons.org/licenses/by/4.0/deed.de 2023-10-09 OPUS4-24557 Zeitschriftenartikel Auersch, Lutz; Maldonado, M. Interaction véhicule-voie-sol et vibrations dues aux trains - Modélisations et vérifications expérimentales Cet article présente plusieurs modèles numériques pour l’étude des phénomènes vibratoires lors du passage d’un train. Les modèles permettent d’estimer la propagation des ondes et les réceptances pour le sol et la voie. Le sol multicouche et le couplage voie-sol sont traités par une (double) intégration sur les nombres d’onde. Les raideurs dynamiques de la voie et du véhicule sont combinées et les forces d’excitation roue-rail dues aux irrégularités de la voie et des roues sont calculées. Ces forces d’excitation permettent de simuler les vibrations du sol lors du passage d’un train. Les modèles sont validés par comparaison avec des mesures sur deux sites, en France et en Allemagne. Les vibrations calculées correspondent bien aux vibrations mesurées. ---------------------------------------------------------------------------------------------------- This contribution presents models that are necessary to calculate the vibrations due to the passage of a train. The models allow to calculate the propagation of the waves and the receptances of the soil and the track. The layered soil and the coupling with the track are treated by a (double) integration in wavenumber domain. The dynamic stiffnesses of the track and vehicle are combined and the excitation forces due to the irregularities of the track and the wheel are calculated. Finally, these excitation forces are used to simulate the ground vibration of a passing train. All these models are validated by a number of different measurements at two sites in France and Germany. Paris Hermès Science : Lavoisier 2011 Revue européenne de mécanique numérique = European journal of computational mechanics 20 5-6 257 280 10.3166/EJCM.20.257-280 2016-02-19