大跨度钢管混凝土桁式拱桥非线性稳定性分析

Nonlinear Buckling Analysis of Large Span CFST Truss Arch Bridge

大跨度钢管混凝土拱桥的宽跨比较小,拱肋的横向稳定成为桥梁安全的关键问题。目前对钢管混凝土拱桥的稳定分析主要采用弹性理论,同时选用较大的稳定系数来保证桥梁安全。介绍同时考虑材料非线性和几何非线性的钢管混凝土拱桥稳定性分析方法,并采用该方法对南浦大桥的稳定性进行分析,结果表明几何非线性对该桥稳定性影响较小,而材料非线性对该桥稳定性影响较大。提出在分析钢管混凝土拱桥稳定性同时应考虑几何非线性和材料非线性的结论。

The stability of arch ribs is the key to bridge safety of large span CFST for the smaller width to span. Elastic theory is been used for stability analysis at present, and biggish buckling factor has been choused for the safety of bridge. In this paper, the global buckling analytic method has been recommended considering geometrical nonlinearity and material nonlinearity, and Chun＇an Nanpu large bridge has been analyzed by the method. The results indicate that influence of geometrical nonlinearity is little and material nonlinearity is quite great. Based our studied, the conclusion that the influence of geometrical nonlinearity and material nonlinearity must been considered in analysis of CFST arch bridge has been recommended.