Abstract： Spatial non-stationary stochastic responses of train-bridge coupling system were analyzed with three-span simple supported girder bridge. Mean value was obtained when the coupling system was only under the determinably load. Pseudo-Excitation Method (PEM) was applied to transformed the track irregularities into the superposition of a series of deterministic pseudo harmonic surface unevenness. Auto-spectral density of the responses had been integrated and the mean-square deviation were found. Maximum and minimum value of the responses were obtained based on 3 principle. Larger value was chosen from the absolue value of the maximum and minimum for the representative one of the responses. Variation trend of the responses were discussed under different speed. The results show that acceleration of car body, lateral responses in bridge midspan and lateral wheel/rail force have large randomness and track irregularities are the major factors. Vertical responses in bridge midspan and vertical wheel/rail force were caused by determinably load. Responses of the bridge did not increase with the increase in train velocity, but responses of car body and wheel/rail force did.
2012, Vol. 31 
