Calculations of ground vibrations from heavy-freight trains

Railway-induced ground vibrations may cause noticeable movements of nearby buildings that result in damage or disamenity, both directly and by generating structure-borne noise. Both effects depend strongly on the spectra of railway-induced ground vibrations that, in turn, are determined by the contributions of differenl excitation mechanisms and by soil properties. Spectra of railway-induced ground vibrations, including train-speed dependent components, have been studied experimentally, and qualitative analysis of the quasi-static excitation mechanism has been attempted. However, no rigorous theoretical investigations of railway generated ground vibrations have been carried out and no quantitatively calculated spectra exist in the literature. In this paper we consider theoretically the effect of quasi-static pressure of wheel axles onto the track-soil system. In the case of welded rails and perfect wheels, this mechanism is the major contributor to trainspeed-dependent components of the low-frequency vibration spectra (up to 50 Hz), including the so called passage frequency fp = v/d, where v is train speed and d is distance between sleepers.