Dynamic Analysis Of Train-bridge Interaction System Considering Vessel Collision And Pier Damage

With the rapid development of high-speed railway and the gradual increase of train speed, bridge structure has occupied a large proportion in high-speed railway line. Thus, bridge vibration problems become increasingly serious, and the vessel collision on the bridges across the rivers also become more frequent. In this dissertation, based on the vehicle-bridge interaction vibration theory, the dynamic responses of the train-bridge interaction system subjected to vessel collision load and running safety of the train are studied. With the consideration of the pier damage induced by the collision load, the running safety of the train on the bridge is also analyzed. The main research contents are shown as follows:(1) The serious accidents of bridges caused by the vessel collisions and the related research situation in China and abroad are reviewed, and the research contents and analysis methods of train-bridge coupling vibration are summarized. The empirical formulas for vessel collision load in the codes are concluded.(2) The vehicle-bridge interaction analysis model subjected to vessel collision load is established, in which the vehicle subsystem is established according to multi-rigid-body dynamics theory, and the bridge subsystem is established by using the Finite Element software of ANSYS. The two subsystems are connected through vertical and lateral wheel-rail close contact assumption, and the vessel collision load is loaded on the corresponding location on the pier in the form of nodal time history load. The dynamic equations of train-bridge system are solved by the whole process iterative method.(3) By taking 5×32m simply-supported bridge on the Beijing-Shanghai high-speed railway as a case study, the dynamic responses of train-bridge interaction system with and without the vessel collision load are calculated and analyzed. The influence of the train speed, colliding position of vessel collision and cross-section type of the pier on the dynamic responses of train-bridge system is considered. The results indicate that the lateral responses of the bridge under vessel collision load are remarkably increased, and the running safety of the vehicle is also greatly influenced.(4) The dynamic responses of train-bridge interaction system are studied with the consideration of the local damage of the pier by reducing local stiffness of the collided bridge pier. The influences of local damage level and damage location on the dynamic responses of train-bridge system are calculated and analyzed. The research results show that the dynamic responses of train-bridge interaction system are enlarged if the damage at the bottom of the bridge pier caused by collision load is considered.