千米级斜拉桥施工过程中主梁的预转折角研究

斜拉桥安装、张拉、起拱等系统的施工金过程分析和控制技术是一项涉及斜拉桥质量和安全的关键技术问题。本文以某千米级斜拉桥为例，采用一阶最优化计算方法来确定斜拉桥的合理施工状态。以成桥后主梁的线形为目标函数，施工中主梁节段的预转折角为设计变量，建立了斜拉桥施工控制的空间非线性有限元分析模型，模拟了钢箱主梁的悬臂拼装过程，求出各施工阶段节段的预转折角。

Study on the prearranged angle of girders in construction state for a thousand-meter scale cable-stayed bridge

As the optimization theory and method to the calculation of cantilever construction of girders is introduced.The example bridge is a long-span cable-stayed bridge of a 1088 m central span length under construction in China.The first order optimization method is used to determine the rational construction cable forces and the prearranged angle of girders.The girder elevation errors and the bending strain energy of the girders and the cable tower is the objective function.By making the objective function least,the tension forces of cables as well as the prearranged angle of girders in construction state are obtained.Using spatial nonlinear FEM,the actual cantilever construction process of steel box-shaped girders is simulated,and the prearranged angles of girders during construction are obtained.