南京长江三桥初步设计方案施工阶段稳定性分析

Stability Analysis of Preliminary Schemes of Nanjing No.3 Bridge in Construction Stage

考虑结构的非线性和构件的极限承载能力,并且计入施工过程变形和应力的叠加效应,对南京长江三桥初步设计方案(独塔双柱、双塔独柱和双塔双柱)钢斜拉桥进行了分析,重点研究了施工全过程中的结构稳定性问题.计算得出3种初步设计方案钢斜拉桥在施工阶段结构的弹性稳定安全系数为4.9～10.2,非线性稳定安全系数为2.1～7.9,表明3种方案钢斜拉桥在施工全过程中的弹性稳定性和非线性稳定性都是足够的.最后,评价了施工过程中极限承载能力状态下的结构安全系数.

Three preliminary schemes of the Nanjing No.3 bridge were investigate by considering the nonlinearity of structures and the ultimate load-carrying capacity of components. They are the schemes of steel cable-stayed bridge with one tower and two poles, or with two towers and one pole, or with two towers and two poles. And in the investigation, the superposition effects of deformations and stresses during the construction were also included. The research was focused on the stability of structures during the construction. The research result shows that elastic stabihty factors for the three schemes are 4.9 to 10.2, and their nonlinear stabihty factors are 2.1 to 7.9, so their elastic stability and nonlinear stability are adequate in construction stage. At last, their stability safety factors in a state of ultimate load-carrying capacity during construction were appraised