三塔大跨度结合梁斜拉桥主跨合龙技术分析

三塔大跨度斜拉桥合龙时各种因素对合龙口的变位和局部受力影响较大,给合龙口调整施工带来了难度.为了得到合理的合龙施工方案,以武汉二七长江大桥为背景,利用MIDAS Civil软件建立该桥有限元计算模型,计算分析了该桥主跨非对称合龙的可行性,并通过敏感性分析确定了温度、压重、调索、对拉等对合龙口两端主梁变位及局部应力影响的程度,得出主跨合龙时应采取的合理措施及合龙步骤.

Technical Analysis for Main Span Closure of Three-Pylon Long Span Composite Girder Cable-Stayed Bridge

Various factors have been blamed for the displacement and the varistion of the local load bearing capacity at the closure gap during the closure of a three-pylon long span cable-stayed bridge,increasing the difficulty of closure gap adjustment.To make a rational closure construction scheme,the Erqi Changjiang River Bridge in Wuhan City was cited as the background,and the MIDAS Civil software was adopted to establish the finite element model of the bridge to calculate and analyze the feasibility of the asymmetrical closure of the main span.Additionally,the sensitivity analysis was carried out to determine the effects of temperature,counterweight,cable adjustment and tensioning on the displacement and local stress of the main girder at the two sides of the closure gap,and to decide on the rational measures steps that should be taken during the main span closure.