超大跨度斜拉桥施工过程随机模拟分析

针对超大跨度斜拉桥由于悬臂施工过程中各种误差的累积可能使其恒载效应具有较强的随机特性,传统的确定性分析方法不能反映这一重要结构特性的问题,采用Monte Carlo法与有限元法相结合的随机模拟方法,将斜拉桥的梁段自重、张拉索力看成随机变量,进行主跨1 088 m的苏通大桥施工过程随机模拟,研究其恒载效应的频度、均值和标准差。研究表明:由于结构系统的变异性,使结构行为呈现一定的随机性;梁段自重、张拉索力变异对钢主梁斜拉桥恒载应力的影响不如对混凝土主梁斜拉桥那么明显,但其对恒载构形的影响不可忽略。

Random Simulation Analysis of Construction Process for Super-Long-Span Cable-Stayed Bridges

Due to the accumulation of errors during the cantilevel construction of super-long-span cable-stayed bridges,response under dead load may be stochastic and it can not be reflected by the traditional method of deterministic structural analysis.Introducing random simulation method which combinating Monte Carlo method with finite element method,considering self-weight of girder and cable tension as random variable,construction process of Sutong Bridge was simulated and frequency,average value,standard deviation of response under dead load were investigated.The result shows that structure behaviour has the random characteristic due to variation of structure system and it is concluded that the influence on geometry can't be omitted while the influence on stress is small.