大跨度实心拱桥现浇钢拱架稳定性分析

Stability analysis of cast-in-place steel arch frame of long-span solid arch bridge

在大跨度实心拱桥施工中,现浇钢拱架采用悬臂拼装,由于其安装环境险峻、杆件变形量大、安装高度较高等因素,除了构件强度及刚度的常规检查外,还要充分论证其整体稳定性,以采取相应的整体加固措施。以贵州地区大跨度实心拱桥现浇施工为背景,根据对拱桥浇筑各工况稳定性计算,详细介绍钢拱架安装、混凝土浇筑中及浇筑完成后整体稳定性变化及现场采取的加固措施,采用钢性横联及合理的缆风点设置方法,增强钢拱架的整体刚度,降低安装及浇筑过程中的横向位移,避免屈曲破坏,为类似工程提供参考。

In the construction of long-span solid arch bridge,the cast-in-place steel arch frame is assembled by cantilever.Due to the factors of steep installation environment,large deformation of members and high installation height,in addition to the routine inspection of component strength and rigidity,the overall stability should be fully demonstrated to take corresponding overall reinforcement measures.Based on the cast-in-place construction of the long-span solid arch bridge in Guizhou area,according to the stability calculation of the arch bridge pouring in various working conditions,this paper introduces in detail the overall stability changes during and after the installation of the steel arch frame,the concrete pouring,and the reinforcement measures taken on site.The steel transverse connection and the reasonable cable wind point setting method are adopted to enhance the overall rigidity of the steel arch frame and reduce the installation and pouring process In order to avoid buckling failure,the lateral displacement in the model can provide reference for similar projects.