大跨度钢斜拉桥制造误差的传播及其效应特性

Fabrication Error Propagation Properties of Key Components of Large-Span Cable-Stayed Bridges with Steel Box Girder

为阐明制造误差效应在大跨度斜拉桥施工控制中的传播问题,对全过程控制条件下超大跨度钢斜拉桥关键构件制造误差效应的效应特性进行了研究,由几何非线性平衡方程推导并建立了全过程控制条件下的误差效应传播方程.在此基础上,以典型的超大跨度斜拉桥——苏通大桥为研究对象,就构件制造误差效应的形成过程、效应特性及其传播特性进行了深入研究.研究表明:所建立的误差传播方程应用和求解方便,适用于大跨度斜拉桥全过程施工控制误差效应的理论研究和计算分析;不同类型构件制造误差的传播特性存在较大差异,随悬臂长度增大,主梁节段间制造角度的误差效应表现出典型的自收敛特性,而主梁节段制造长度的误差效应不具备自收敛特性,施工控制实施时应根据误差效应特性确定科学、合理的误差调控方案.

To clarify the fabrication errors＇ propagating properties in the construction control of a largespan cable-stayed bridge,the effect characteristics of the manufacture errors of key components during the whole construction procedure were investigated. An error propagation equation was developed based on geometrically nonlinear equilibrium equations. By taking Sutong bridge,a typical large-span cablestayed, as research object, an in-depth discussion concerning the forming process, effect characteristics and propagation properties of manufacturing errors was carried out. The research results show that the theoretical method established is feasible and appropriate to analyze and expound the error effects accompanying whole-procedure construction control. There are significant differences among the fabrication error propagation properties of different types of components. With the increase of cantilever length,the error effect of the angle fabrication error between main girder segments is convergent,while the error effect of the length fabrication error is not,so scientific error control schemes are necessary for better control effect.