Spatial train-bridge coupling system non-stationary stochastic responses analysis

The pseudo-excitation method (PEM) was applied in the spatial train-bridge coupling system non-stationary stochastic responses analysis. Track vertical profile irregularity, track alignment irregularity and track height difference irregularity of left and right rails were transformed into the superposition of a series of deterministic pseudo harmonic surface unevenness and non-stationary random vibration analysis was translated into deterministic time-history analysis. Separate iteration was applied in solving the coupling system equation. The maximum and minimum system responses were obtained on the basis of the 3σ principle. PSD of the system responses were discussed. The results show as follows: Responses of the train body, lateral responses of the bridge and lateral wheel-rail forces have large randomness, and track irregularities are the primary influence factors; bridge vertical responses and vertical wheel-rail forces are caused by deterministic loads.