矮塔斜拉桥参数敏感性分析

以开封黄河二桥主桥矮塔斜拉桥为研究对象,采用MIDAS/Civil有限元程序,建立了该桥在最大悬臂施工阶段的有限元计算模型.考虑施工过程中可能出现的桥梁参数变化,分别进行主梁混凝土容重、主梁混凝土弹性模量、主梁截面尺寸、斜拉索弹性模量、斜拉索初张力、主梁预应力荷载和施工荷载敏感性分析,确定出悬臂施工时影响主梁位移和应力的主要设计参数.计算结果表明,主梁混凝土容重、截面尺寸、斜拉索初张力、预应力荷载和施工荷载为主要设计参数,混凝土弹性模量和斜拉索弹性模量为次要设计参数.所得结果可为该桥梁施工控制提供参考.

Parameters' Sensitivity Analysis of Extradosed Cable-stayed Bridge

A 3-dimensional finite element calculating model is established for the main bridge of the 2nd Yellow River bridge in Kaifeng,which is an extradosed cable-stayed bridge,on its maximal cantilever construction stage by using software MIDAS/Civil.By taking into account all kinds of influencing parameters in bridge construction,including the bulk density of reinforced concrete,the Young's modulus of reinforced concrete,the sectional dimension of main girder,the Young's modulus of stayed cables,the initial tension of stayed cables,the prestress of main girder and the construction loads,their sensitivities are calculated respectively and those parameters which have an obvious effect on the displacement and stress of the main girder are picked out.The calculated results indicate that the main designed parameters include the bulk density of reinforced concrete,the sectional dimension of main girder,the initial tension of stayed cables,the prestress of main girder and the construction loads.On the contrary,the Young's modulus of reinforced concrete and the Young's modulus of stayed cables are the secondary designed parameters.The conclusions can be of some help to the construction control of the bridge.