独塔斜拉桥施工阶段抖振响应及抑振分析

Analysis of buffeting response and vibration-restraining for cable-stayed bridge with single tower at construction stage

针对斜拉桥在最大双悬臂阶段的风致振动响应问题,通过考虑气动导纳和气动弹性效应对基于准定常理论的抖振力和自激力表达式进行了修正,并用谐波合成法模拟得到了具有空间相关性的脉动风荷载样本,继而对金马大桥在最大双悬臂阶段的抖振响应进行了分析,并对风载内力和人体舒适度进行了评价。结果表明,该桥的抖振响应对施工人员影响较小。同时,分析表明增设抗风临时拉索是一种简单有效的抑振措施。

In view of the problem of buffeting response of cable-stayed bridge at max twin cantilevers stage, the formulations of buffeting and self-excited forces based on quasi-steady assumptions are modified by considering aerodynamic admittance and memory effect and the turbulent wind load samples which are of spatial correlation property are simulated with cosine wave superposition method. On this basis, analysis of buffeting response for Jinma Bridge at maximum twin cantilevers stage during construction is performed and wind load internal forces and the degree of human comfort is discussed as well. The results show that buffeting response has no effects on constructors. Meanwhile, the buffeting-restraining measure setting temporary wind-resistance cables is analyzed and proved to be simple, efficient and practicable during construction.