斜拉索断裂对斜拉桥动力性能的影响研究

斜拉索断裂后必然会对斜拉桥动力性能产生一定的影响，进而影响到桥梁的通载能力。利用有限元方法针对长江某大型斜拉桥进行数值分析建模，考虑了各种非线性影响因素，对模型施加二期恒载后进行计算检验。验证模型合理性后，针对斜拉索不同断裂位置和数量，对斜拉桥进行了动力性能分析。通过分析得出背索和跨中斜拉索断裂对全桥动力性能影响较大和竖向振型受斜拉索断裂影响较大的结论，可为斜拉桥应急抢修技术方案的制定和平时桥梁的健康监测提供理论依据。

Study of the Effects of the Breaking of Cables on the Dynamic Performance of Cable-stayed Bridges

The breaking of cables is bound to have a certain impact on the dynamic performance of a cablestayed bridge, and further to affect the carrying capability of the bridge. A numerical analysis model taking account of the nonlinear factors for a certain cable-stayed bridge over the Yangtze River is established by means of the finite method in the paper, with it applied to calculating the model with the second permanent load exerted onto it. After rationality of the model is proved, the dynamic performance of the cable-stayed bridge is analyzed according to different locations and numbers of the broken cables. Upon the basis of the analysis it may be concluded that the dynamic performance of the cable-stayed bridge with broken cables is greatly affected by the broken cables on the back and the middle of the cable-stayed bridge and the vertical model of the cable-stayed bridge is also greatly affected by the broken cables, the result of which provides a theoretical basis for working out rush-repair technical schemes for cable-stayed bridges in wartime and the health-monitoring of them in peacetime.