船舶撞击作用下车桥系统动力响应及高速列车运行安全分析

摘要

Taking a vessel collision force as an external excitation,a dynamic model was established for a train-bridge coupled system.A (32+48 +32 )m continuous bridge with PC box-girders and a homemade CRH2 high-speed train were taken as an example.When the vessel collision load acted on the pier,the whole time histories of the train running on the bridge were simulated,and the dynamic responses of the bridge and the train were calculated.The results showed that the vessel collision load greatly raises the dynamic responses of the bridge,and remarkably affects the running safety of the CRH2 train.A method to evaluate the running safety of high-speed trains on a bridge subjected to collision load was investigated, and the influences of train speed and collision intensity on the train running safety were comprehensively analyzed,furthermore the safety threshold curve of train-speed versus collision intensity was proposed.%将船舶撞击力时程作为系统的外部激励，建立了撞击荷载作用下的车桥系统动力分析模型。以一座（32＋48＋32）m双线预应力混凝土连续梁桥和国产CRH2高速列车为例，模拟船舶撞击力作用于桥墩时列车过桥的全过程，分析了桥梁和车辆的动力响应。结果表明：船舶撞击作用大幅度增大了桥梁的横向位移和加速度响应，显著影响了桥上高速列车的运行安全。探讨了船舶撞击荷载作用下的桥上高速列车走行安全评价方法，综合分析了列车速度和荷载撞击强度对列车运行安全的影响，在此基础上给出了列车速度－撞击力强度安全阈值曲线。