Random dynamic analysis of multi-span bridge under track irregularity andhorizontal traveling seismic waves

Abstract

This paper investigates random vibrations of a coupled train-bridge system subjected to the horizontal traveling seismic waves. Each vehicle in the train is described as a 27 degrees of freedom system with rigid bodies and suspensions, and the track and bridge are modeled as 3D Euler beam elements. The random track irregularity and random seismic excitations are transformed into a series of deterministic pseudo-excitations by using the pseudo-excitation method (PEM). The equations of motion of the coupled system subjected to the transformed pseudo-excitations are solved, and then the random responses, which are standard deviations of the responses, can be obtained. In a case study, the standard deviations (SD) of the responses were simulated for a China Pioneer EMU train traversing a 10-span simply supported bridge with different seismic propagation velocities. From the results, it was confirmed that the seismic propagation velocity has a significant influence on random responses.