无应力状态控制法斜拉桥安装计算的应用

Application of Unstressed State Control Method to Calculation for Erection of Cable-Stayed Bridge

利用分阶段施工桥梁结构的力学平衡方程和无应力状态按制法的基本原理确定斜拉桥施工中间过程理想状态。以桥梁构件单元的无应力状态量必须满足成桥目标状态要求作为控制条件,直接由斜拉桥最终设计成桥目标状态求解桥梁施工过程状态的内力和线形。混凝土斜拉桥施工过程的收缩和徐变实际上是改变了构件单元的无应力长度和无应力曲率,应通过施工中的预拱度来调整。

The mechanical equilibrium equations for bridge structures constructed in stages and the fundamental principle of unstressed state control method are used to determine the ideal state in the construction interim process of a cable-stayed bridge. The unstressed state amount of the bridge structural elements that must satisfy the requirements for the completion target state is taken as the control condition and the internal force and geometric shape of the construction process state are to be directly calculated from the final designed completion target state of the bridge. The shrinkage and creep of a concrete cable-stayed bridge in the construction process are in fact the problem that the unstressed length and unstressed curvature of the structural elements have been changed, which should be resolved by adjusting the precamber of the bridge in the constructlon process.