Dynamic Response of Spatial Train-Track-Bridge Interaction System Due to Unsupported Track Using Virtual Work Principle

An improved spatial vehicle–track–bridge interaction system considering the unsupported track is proposed using virtual work principle. When fails to be supported due defects under track, corresponding bridge–rail connection coupled matrix should removed. Using dynamic model, a novel numerical analysis of unilateral and bilateral sleepers in bridge subgrade carried out. The results indicate that wheel–rail contact force changes dramatically when vehicles pass through track. has little effect on displacement bridge, but it increases acceleration bridge. increase significantly with expansion driving speed. For sleepers, response side slightly smaller than sleeper, while limited other normal support.