分幅不对称索面钢箱梁斜拉桥主梁安装控制  

Erection Control of Main Girder of Steel Box Girder Cable-Stayed Bridge with Separated Decks and Asymmetric Cable Planes

作　　者：贾少敏[1] 赵雷[1] 卜一之[1] 

机构地区：[1]西南交通大学土木工程学院,四川成都610031

出　　处：《桥梁建设》2014年第3期114-119,共6页Bridge Construction

基　　金：交通运输部科技项目(2010-353-333-130)~~

摘　　要：针对分幅、不对称索面钢箱梁斜拉桥的结构特点和安装阶段面临的困难,基于几何控制法的原理,以六塔、双幅、空间四索面的嘉绍大桥主航道桥为研究对象,给出了该类桥安装时主梁标高、轴线、横坡的控制方法及操作步骤,即在匹配阶段,通过调整新起吊主梁节段与已安装主梁节段的相对位置来保证主梁线形平顺,使主梁轴线、横坡及2幅主梁间距满足精度要求,又可大幅减小温度及风对施工进度的影响;在斜拉索张拉阶段,通过斜拉索无应力索长的调整,使主梁标高、2幅主梁内侧相对标高满足精度要求,又可方便后续横梁的安装。施工实践表明:嘉绍大桥主航道桥主梁安装顺利,合龙后实测主梁线形平顺,最大标高误差远小于规定的限值。Abstract： In view of the structural features of the steel box girder cable-stayed bridge with separated decks and asymmetric cable planes and the difficulties that may be confronted at the erection stage, the main ship channel bridge of the Jiashao Bridge with six pylons, separated two decks and spatial four cable planes was taken as the research object, the control methods for the elevation, axial line and transverse slope of the main girder of the bridge of the same type at the erection stage and the related working procedures were worked out based on the principle of the geometry control method. Specifically, at the matching and erection stage of the girder blocks of the bridge, the smooth geometric shapes of the main girder were to be guaranteed by adjusting the relative positions between the newly and the previously installed blocks. The adjusting of the relative positions not only could make the axial line and transverse slope of the main girder and the spacing distance between the two decks meet the accuracy requirements, but also could reduce the impact of the temperatures and wind on the construction progress to a great extent. At the tensioning stage of the stay cables of the bridge, by adjusting the unstressed length of the cables, the elevation of the main girder and the relative elevation of the inner sides of the two decks could be made to meet the accuracy requirements and at the same time to facilitate the subsequent installation of the cross beams. The construction practice shows that the erection of the main girder of the main ship channel bridge of the Jiashao Bridge has gone on well, the measured geometric shapes of the main girder after closure are smooth and the maximum elevation error is far less than the specified limit values. Key words： cable-stayed bridge; steel box girder; asymmetric cable planes; erection control; geometry control method; error control; unstressed state method; geometric shape

关 键 词：斜拉桥 钢箱梁 不对称索面 安装控制 几何控制法 误差控制 无应力状态法 线形 

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]