Calculation of low-frequency ground vibrations from railway trains

Understanding physical mechanisms of railway-induced groundvibrations is an essential prerequisite for reducing their impact on the built environment. In this paper the theory of generation of low-frequencygroundvibrations by moving trains in the framework of the quasi-static wheel pressure effect is developed using the Green's function formalism. Mechanical properties of the rail track and parameters of train and soil (including contact nonlinearity of the track-soil system) are taken into account in a theoretical model that considers generation of elastic waves by each sleeper of the track subjected to the action of all wheel axles. The analytical expressions have been derived and the numerical calculations have been carried out for the vibration spectra generated by trains. It is shown that these spectra depend strongly on the mechanical properties of soil, on the axle loads of the carriages and on the geometrical parameters of the track and train. Some practical methods are suggested to modify the spectra of railway-induced groundvibrations and to decrease their level in the chosen frequency intervals.