大跨度钢索和CFRP索斜拉桥车桥耦合振动研究

以跨度600m～1400m的大跨度斜拉桥为对象,应用考虑拉索侧向振动影响的车桥耦合振动分析方法研究了钢索和CFRP索斜拉桥的交通振动响应,比较了车辆计算模型、行车速度对计算结果的影响,并分析了斜拉桥的动力冲击系数。研究结果表明,大跨度斜拉桥主梁的振动响应以静位移和长周期振动成分为主,拉索局部侧向振动不明显,车辆计算模型对结构振动响应的影响十分有限,行车速度的提高增加了结构的动力系数,两种拉索材料对斜拉桥在车辆荷载下的振动响应影响很小,斜拉桥的动力系数离散性大且与构件类型有关。

STUDY ON VIBRATION OF LONG-SPAN CABLE-STAYED BRIDGE WITH STEEL AND CFRP CABLES DUE TO MOVING VEHICLES

The method of vehicle-bridge coupling vibration considering lateral vibration of cables was adopted for analyzing traffic vibration responses of steel and CFRP cable-stayed bridges with spans ranging from 600m to 1400m. The influences of vehicle model and running speed of vehicle were investigated,and the dynamic impact factors of cable-stayed bridges were discussed. The results show that the static displacement and the long-period vibrations are the main components of traffic vibration responses of long-span cable-stayed bridge girders. The lateral vibration of cables is not obvious. The difference in vehicle models has little effect on structure dynamic responses. The impact factors of structure increases with increasing speed of vehicle. The dynamic responses of steel and CFRP cable-stayed bridges are nearly identical. The impact factors of cable-stayed bridge have a great variation and are related to the type of members.