A numerical model formulation for the underground railway vibration prediction

This paper discusses a theoretical-numerical model formulation for the prediction of vibrations from underground railway traffic. The model takes into consideration transfer junctions between the track lying in the underground tunnel and a free field. The rolling stock can be modeled as a multi-body vehicle chain. The dynamic axle loads due to the rails and wheels irregularities may be estimated. In the model a wheel-rail single point Hertzian contact is assumed. As for the dynamic track and tunnel compliance the transfer functions can be computed and/or measured. The entire model can be validated by means of vibration "in-situ" measurements.