大跨度钢管混凝土拱桥的极限承载能力分析

介绍了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，采用该方法对茅草街大桥模型试验的极限承载能力进行了分析，并讨论了不同的布载方式与风荷载对于结构极限承载能力的影响。通过计算分析表明，只有同时考虑结构的几何非线性与材料非线性，才能对结构的极限承载能力做出正确的评估。

Ultimate Load-carrying Capacity of CFST Arch Bridge with Long-span

Considering geometrical nonlinearity and material nonlinearity, the analysis of stability for a concrete-filled steel tubular arch-bridge is presented and a large bridge model has been proposed by the method. Results show that the overall safety of a long-span arch bridge depends on the two nonlinearities. It depends less on geometrical nonlinearity and primarily on the material nonlinearity of individual ridge element. In comparison with the result of linear elastic stability analysis, the influence of geometrical nonlinearity leads to the overall safety reduction 10 %, but the effects of the two nonlinearities reach 40 %. Finally, the effects of different load distributions and wind loads on the ultimate load-carrying capacity of the bridge are investigated. Results show that designed wind loads affect less the overall safety of structure and influence of nonlinearity is more notable in haft brldge-loading sequence.