Mitigation of Railway Traffic Induced Vibration: The Influence of barriers in Elastic Half-Space

In recent years, the interest in vibrations due to railway traffic is increasing in all developed countries, and it is requires developing both experimental and theoretical studies. In this paper, the problem of vibrations induced by trains and their propagation through the soil is studied. In particular, we focus our attention on the vibration induced by moving trains and on the effects of such vibrations on the foundation of nearby buildings. The interaction between propagating waves induced by moving trains and buildings foundation is a problem which does not admit straightforward analytical solution; therefore, the phenomenon can be modelled through the finite element method. Firstly, we analyze the theoretical aspects of the problem by considering constant or harmonic loads moving along a straight railway track; then, we characterize the transfer function soil-railway and the response function of the entire system. What we want to investigate is the wave propagation in elastic semispace and the track-soil interaction in terms of stress and strain. Afterwards, we study the problem considering the presence in the ground of one discontinuity such as a barrier having certain deepness. A study to investigate the efficiency of barriers with the variation of the material was developed, then different numerical simulations are analyzed in order to optimize the FE model and to study how the wave propagation and the track-soil interaction are influenced by the membrane which can be seen as damping barrier.