荆岳长江公路大桥中跨合龙施工技术  

Construction Techniques for Closure of Central Span of Jingyue Changjiang River Highway Bridge

作　　者：涂光亚[1] 颜东煌[1] 陈常松[1] 易壮鹏[1] 

机构地区：[1]长沙理工大学土木与建筑学院,湖南长沙410114

出　　处：《桥梁建设》2013年第4期105-109,共5页Bridge Construction

摘　　要：荆岳长江公路大桥主桥为跨径布置(100+298)m+816m+(80+75+75)m的混合梁斜拉桥,主梁由扁平钢箱梁和分离式混凝土边箱梁组成,中跨钢箱梁合龙段长16.4m,重305t,采用2台桥面吊机抬吊施工。该桥中跨合龙采用半配切半顶推的施工方案,通过统计方法预测合龙温度为22℃,在此基础上考虑多种因素影响,精确计算合龙段无应力下料长度为16454.4mm,将合龙段在工厂精确匹配预制,设置牵引装置调整合龙口宽度,采用逐缝调整合龙缝宽度的方法进行合龙段位形调整,最终顺利实现中跨的高精度合龙。实践证明,采用该合龙施工技术能减轻对合龙温度的依赖,缩短合龙施工时间,提高合龙施工精度和质量。The main bridge of Jingyue Changjiang River Highway Bridge is a hybrid girder cable-stayed bridge with span arrangement of （100＋298） m＋816 m＋（80＋75＋75） m. The main girders of the bridge consist of the flat steel box girder and separated concrete edge box girders. The closure block for the steel box girder of the central span is 16.4 m in length and 305 t in weight, which was lifted and installed by two sets of the deck cranes. The construction scheme for the closure of the central span was that according to the statistic analysis method, of partial cutting and partial pushing of the girder and the closure temperature was predicted to be 22 ℃. Based on the prepared construction scheme and the temperature prediction, the unstressed material cutting length of the closure block was precisely calculated to be 16 454.4 mm, considering numerous factors having influences on the closure and the block was precisely match prefabricated in the workshop. The hauling devices were arranged for adjusting the width of the closure gap, the location and geometric shapes of the closure block were adjusted, using the method of adjusting the closure joint width welding seam by welding seam and the central span was finally smoothly closed with high precision. Practice proves that the closure techniques applied to the bridge can lessen the dependence on the closure temperatures, shorten the construction time for the closure and raise the construction precision and quality.

关 键 词：斜拉桥 混合梁 箱形梁 合龙 配切 顶推 关键技术 桥梁施工 

分 类 号：U448.27[建筑科学—桥梁与隧道工程] U445.4[交通运输工程—道路与铁道工程]