中文摘要：

钢管混凝土组合高墩连续刚构桥体系可靠度计算存在钢管混凝土组合高墩受力分析复杂,连续刚构桥梁失效模式较多,其功能函数不存在显式等问题。采用MIDAS有限元软件对结构进行较准确的模拟和受力分析,然后根据分析结果选取最高墩的稳定性失效和关键截面的拉、压应力失效模式。在MATLAB语言的平台上利用二次序列响应面法将隐式功能函数显式地表达出来,再经过多次的迭代计算实现钢管混凝土组合高墩连续刚构体系可靠指标的计算。研究表明,该方法迭代次数少,效率较高,可实现同类桥梁功能函数重构和体系可靠度计算。

英文摘要：

There are a lot of problem on calculation of system reliability index of concrete-filled steel tubular（CFST） continuous rigid frame bridge with high-rise piers,such as complex stress analysis of high-rise piers,numerous failure modes of continuous rigid frame bridge,and non-explicit performance function.More accurate simulation and stress analysis of the structure were performed by using finite element software MIDAS,and the three types of failure mode（the stability failure of the highest pier,and tension or compression stress failure of key sections） were selected accordingly.Implicit performance function was explicitly expressed by quadratic sequence response surface method in MATLAB language platform.Then calculation of system reliability index of CFST continuous rigid frame bridge with high-rise piers was realized after several iterations.The result shows that the iterations of this method is less and efficiency,and can achieve reconstruction of performance function and calculation of system reliability of similar bridges.