桥梁结构刚度对高速列车—轨道—桥梁耦合系统动力特性的影响

摘要

The dynamic performances of high-speed train-track bridge coupled system are significantly affected by the structure stiffness of bridge, which directly influences the running safety and ride comfort of a train on the bridge. Based on train-track-bridge dynamic interaction theory, the influences of structure stiffness of bridge on the dynamic responses of the coupled system were analyzed using the train-track-bridge dynamic simulation software TTBSIM2. 0, in which a simply supported bridge and double-block ballastless track both commonly used in high-speed railway were chosen to be the study object. Results show that when the stiffness of beam or the lateral stiffness of piers is insufficient, the major dynamic indexes of train and bridge increase dramatically with the decrease of the stiffness, and the running safety and the ride comfort of the train are deteriorated severely. In particular, the resonance of beam excited by passing train may occur if the vertical stiffness of beam is insufficient. When the structure stiffness of bridge satisfies the design code, the dynamic responses of train-bridge system vary little with the change of stiffness. The running speed and track irregularities become the main factors to influence the running safety and ride comfort of train.%桥梁结构刚度对高速列车—轨道—桥梁耦合系统的动力学特性具有重要的影响,直接关系到桥上列车的行车安全性和运行平稳性.基于列车—轨道—桥梁动力相互作用理论,以高速铁路常用的简支箱梁桥和双块式无砟轨道为研究对象,采用列车—轨道—桥梁动力学仿真通用软件TTBSIM2.0,研究桥梁结构刚度对高速列车—轨道—桥梁耦合系统动力性能的影响规律.结果表明:当桥梁梁体的刚度或者桥墩的横向刚度不足时,车辆和桥梁的相关动力性能指标将随着刚度的减少而急剧增大,严重影响列车过桥时的安全性和平稳性；当梁体垂向刚度不足时,有可能会引发车桥共振现象；当桥梁结构刚度满足设计规范要求时,车桥系统动力响应指标随刚度变化不明显,此时行车速度和轨道不平顺成为影响行车安全性和平稳性的主要因素.