An improved model for the nonlinear simulation of the high-speed vehicle-track-bridge coupling system under seismic shaking

With the continuous development of high-speed railway (HSR) construction technology, many HSR bridges are close to near-fault earthquake zones. Due to the short warning time for earthquakes occurring in these areas, the scene of trains running on the HSR bridges under earthquakes will become more and more common. In order to effectively evaluate the train running safety performance on the HSR bridge under earthquakes, an improved model for the nonlinear simulation of the high-speed vehicle-track-bridge (VTB) coupling system under seismic shaking is proposed. The commercial finite element software was utilized for the general modeling of track-bridge structure, and nonlinear hysteric behaviors of key components were realized by using the local nonlinearity correction method. By adopting the unconditional stable explicit dynamic integration algorithm and an efficient wheel-rail contact model, an explicit dynamic solution framework is established. It can efficiently solve the nonlinear coupled vibration of the VTB system under earthquakes. Finally, based on the improved model developed in this paper, the influence of hysteretic behaviors of bridge bearings on the nonlinear coupling vibration of the VTB system under near-fault earthquakes is discussed.