车桥耦合系统动力分析的模态综合技术

当高速重载车辆或者装载贵重和精密仪器的车辆过桥时 ,必须对车也进行动力分析 ,以保证车、桥以及车内物品的安全。为此对车和桥均进行有限元离散 ,建立耦合系统模型 ,在求得桥的响应的同时 ,得到车上关键点的位移。移动质量和移动阻尼使整体系统矩阵不对称且具有时变性 ,引入模态综合技术有效降低耦合系统自由度 ,减小计算量。算例显示某些情形下耦合系统响应分析中车的动力放大效应比桥更显著。对运载重要设备的车辆来说 ,车载装置的安全与桥的安全具有同样重要的意义 ,都应该加以研究。

Dynamic analysis of a coupled vehicle-bridge system using modal synthesis

High-speed or heavy vehicles crossing bridges, must be analyzed dynamically to guarantee the safety of the vehicle and the bridge. Both the vehicle and the bridge were analyzed with a coupled finite element model to calculate the response of them. The system matrices were asymmetric and the problem was time dependent because of the moving mass and the moving damping. The DOF of the coupled system were reduced using modal synthesis. Examples show that the dynamic scale-up of the vehicle is greater than that of the bridge for some circumstances. Especially with heavy vehicles, the equipments safety is as important as the bridge safety, so both of them should be investigated.