斜拉桥施工过程中的力学行为研究是一项涉及斜拉桥质量和安全的关键技术问题。采用空间非线性 有限元模拟了某大跨度预应力混凝土斜拉桥主梁的悬臂浇筑过程，引入一阶最优化计算方法来确定斜拉桥的合 理施工状态，求出各施工阶段的斜拉索张拉索力和主梁的预抛高值，并讨论了物理非线性和几何非线性等因素 对桥梁施工的影响，提出了减小非线性影响的措施。。

Because of the increasing span of concrete cable-stayed bridge,  the construction simulation recently becomes more focusing on both the design and construction.  This paper introduces the optimization theory and method into the calculation of cantilever construction of girders. The example bridge is a long-span prestressed concrete cable-stayed bridge with a 370 m central span length under construction in China. Using spatial nonlinear FEM,  the actual cantilever construction process of concrete box-shaped girders is simulated,  the tensioning force of cables as well as the prearranged height of girders in construction state is obtained. At the same time, the influence of structural geometric nonlinear characteristics and physics nonlinear characteristics in the cable force optimum are investigated,  the measures to reduce the influence are put forward.