宜宾长江大桥斜拉桥的抗风性能分析

对宜宾长江大桥施工状态和成桥状态的动力特性进行了计算,分析了主梁的三分力系数取值,验算了桥梁的颤振稳定性和静力稳定性,结果表明,无论在施工阶段的最大双悬臂状态或最大单悬臂状态,还是在成桥状态,抗风稳定性均十分安全,不会发生静力扭转发散失稳。建议对斜拉索采取减振措施,可在设置内置橡胶圈阻尼器的基础上,再增设磁流变液阻尼器。

Analysis of Wind-Resistant Behavior of Cable-Stayed Bridge of Yibin Changjiang River Bridge

The dynamic behavior of the cable-stayed bridge of Yibin Changjiang River Bridge at both construction and completion stages is calculated.The selected values of three-component coefficients of the main girder of the bridge are analyzed and the flutter and static stability thereof are checked through calculations.The results indicate that the wind-resistant stability of the bridge either in the state of the longest double cantilevers or single cantilever at construction stage or at completion stage is extremely safe and the divergent instability due to static torsion will not occur.Finally,proposals are made to add more damping measures to the stay cables,i.e.the magnetorheological fluid dampers could be added in addition to the internally-set rubber collar dampers.