长跨柔性悬索桥风致抖振响应分析

以某主跨500 m的大跨度悬索桥为工程背景,对长跨柔性悬索桥在脉动风荷载作用下的抖振响应进行了分析和计算,得到了一些有借鉴性的结论。模态分析表明,大跨度悬索桥的自振频率较低,为典型的风敏感柔性结构。当同时考虑抖振力和自激力时,根据极值理论可以得到悬索桥主梁的抖振位移响应极值,结果表明,竖向、水平和扭转方向的最大抖振位移响应极值均发生在主跨跨中处,且数值较大,在结构设计中不容忽略。

Wind-induced buffeting response analysis of long span flexible suspension bridge

Based on the engineering background of a long-span suspension bridge with a main span of 500 m, the buffeting response of a long-span flexible suspension bridge under fluctuating wind loads is analyzed and calculated, and some useful conclusions are obtained. Modal analysis shows that the natural vibration frequency of long-span suspension bridge is low, which is a typical wind-sensitive flexible structure. When the buffeting force and self-excited force are considered at the same time, the maximum buffeting displacement response of the main beam of the suspension bridge can be obtained according to the extreme value theory. The results show that the maximum buffeting displacement response in the vertical, horizontal and torsional directions all occur in the middle of the main span, and the value is large, which cannot be ignored in the structural design.