大跨度悬索拱桥极限承载能力研究

Study on ultimate load-carrying capacity of long-span suspended arch bridge

首先介绍了悬索拱桥的特点和极限承载能力计算方法，然后基于有限元理论，考虑施工阶段的位移和应力的叠加效应、几何非线性、材料非线性以及拱肋等构件的初始缺陷的影响，对某铁路悬索拱桥的极限承载力进行了分析，计算得出结构在施工阶段弹性稳定安全系数为5．2～5．8，非弹性稳定安全系数为2．0～2．6；在运营阶段其弹性稳定安全系数为4．9-5．1，非弹性稳定安全系数为1．7～1．9，表明该桥弹性稳定性和非弹性稳定性都是足够的。其计算方法和结果对于悬索拱桥的计算及设计理论有一定的借鉴价值。

The characteristics of suspended arch bridge and the method for calculating the ultimate load-carrying capacity are introduced firstly. Then based on the theory of finite element, the ultimate load-carrying capacity of a railway suspended arch bridge is analyzed considering the deformation during construction and the superposition effect of stresses, geometric nonlinearity, material nonlinearity and the effect of initial defect in the members （ such as arch rib） during construction. The research results show that the elastic stability factors are 5.2 to 5.8 ; the non-elastic stability factors are 2.0 to 2.6 in the construction stage ; the elastic stability factors are 4.9 to 5.1 ; the non-elastic stability factors are 1.7 to 1.9 in the service stage. So the elastic stability and the non-elastic stability are adequate in construction stage and service stage. Finally, a conclusion is drawn that the calculating method and the results are valuable for the calculation and design theory of suspended arch bridge.