PC斜拉桥辅助墩拉力摆断裂后的状态模拟

Simulation on the state after fracture of tension rocker bearing cables at auxiliary piers in a PC cable-stayed bridge

以天津永和大桥拉力摆断裂为例,介绍辅助墩拉力摆的断裂情况及其成因.为实现拉力摆断裂后的结构状态模拟,分析了拉力摆断裂引起的结构状态指标(桥面线形、塔顶偏位、索力及辅助墩支座脱空等)的变化,给出拉力摆断裂后结构状态模拟的目标和误差控制准则.在分析斜拉索索力与结构变位指标相关性的基础上,研究了拉力摆断裂后结构状态模拟的实现途径及步骤,形成一种基于现状检测结果和索力调整的PC斜拉桥结构状态反演分析技术.模拟计算结果表明,该分析技术能较全面反映检测结果,与结构实际受力状态吻合,有工程应用价值.

The fracture and the causes of its tension rocker bearing cables installed at auxiliary piers of the Yonghe Bridge in Tianjin were addressed. The structural state indexes such as the deck alignment, displacements at top of pylons, stayed cable forces and disengaging distance between compression bearings and its main girder were analyzed. The objectives and error control criteria for structural state simulation were presented. Moreover, the correlations of cable stayed forces and structural deformation indexes are analyzed, and the method of structural state simulation was studied. Finally, an inversion analysis method based on adjusting cable stayed forces was esta lished. Calculation results show that this method can fully reflect detection results and actual structural state changes, and it can be useful to other projects.