Abstract:In this paper,three models for vehicle-bridge coupled vibrations, namely moving spring mass system,two-degree-of freedom vehicle model and fourdegree-of freedom vehicle model were derived according to vibration theory andthe hypothesis of Euler-Bernulli beam.Through using modal analysis method,thepartial differential function was changed to differential function which varied with time.Based on Runge-Kutta method,the vehicle-bridge coupled vibration eation were solved with MATLAB.The results show that the three models all can reasonably reflect the rule of bridge vibration under moving loads.However,more authentic results can be obtained with taking the vehicle body rigidity into account.