中文摘要：

用多刚体模拟车辆,梁格法简化桥面板,以等效质量的形式施加二期恒载。基于车辆、桥梁空间振动模型,建立桥梁—轻轨车—汽车耦合系统的空间振动方程。采用直接积分法求解此方程,并编制相应程序。以某大跨度斜拉桥方案为例,计算其自振特性,进行大跨度斜拉桥—轻轨车—汽车耦合系统的车桥振动分析,并讨论二期恒载对自振频率和车桥耦合振动响应的影响。研究结果表明：二期恒载会使桥梁结构的自振频率减小,对桥梁结构的位移响应影响较小,但对加速度响应影响明显。

英文摘要：

The vehicle was modeled by rigid dynamics method,the bridge deck was simplified by grillage method,and the secondary dead load was taken into account in the form of equivalent quality.Based on the spatial vibration analysis models of vehicle and bridge,the equation of the bridge-monorail train-vehicle system was established.The equation was solved by direct integral method,and a program was compiled.A long-span cable-stayed bridge was taken as an example,the dynamic characteristics of the bridge were calculated,the coupling vibration responses of long-span cable-stayed bridge-monorail train-vehicle system were analyzed,and the influence of second dead loads on the natural vibration frequencies of the bridge and the vibration response of the vehicle-bridge coupling system was discussed.The results show that the secondary dead loads can reduce the vibration frequencies of the bridge,though it hardly affects the displacement of the bridge,it has significant influence on the acceleration.