Response Analysis of Railway Bridge with High Piers due to Vehicle Braking

Research purposes: To investigate the longitudinal vibration performance of railway bridge with high piers induced by the action of braking of high-speed train, a longitudinal dynamic analysis model for a coupled train-track-bridge system is established using the software TTBLS-DYNA developed autonomously. The finite element method is adopted to create track-bridge 3-D spatial model and the vehicle subsystem is modeled by rigid body dynamics. According to the braking deceleration characteristic curve of the EMU train, a numerical integration method is adopted to solve the dynamic equations of vehicle and bridge respectively, and then the dynamic response of the interaction system is analyzed. Take Shijiagou simply-supported bridge with high piers as numerical example to analyze train-track-bridge longitudinal coupled vibration. Research conclusions: (1) The longitudinal vibration of the bridge with high piers is generally small, the maximum displacement and acceleration value are 0.17 mm and 58 mm/s2 respectively. (2) The longitudinal deformation of beam has accumulative character during the braking procedure of EMU, the maximum displacement occurs before the moment of train stopping. In contrast, the maximum longitudinal acceleration occurs at the moment of train stopping. (3) The maximum value of the bending moment at the bottom of all piers is 1152.0 kN·m, which is only 31.5% of the value 3960.7 kN·m obtained by the static force calculation method according to the code for design on railway bridge and culvert in China. It indicates that the braking force of high-speed train obtained from the code possess a higher safety stock. (4) The research results of this paper can provide good references for design of railway bridges with high piers. © 2017, Editorial Department of Journal of Railway Engineering Society. All right reserved.