沪通长江大桥主航道桥全焊桁片总拼及焊接技术  

Techniques for Assembly and Welding of Fully-Welded Truss of Main Navigational Channel Bridge of Hutong Changjiang River Bridge

作　　者：殷秀凯 YIN Xiu-kai(China Railway Jiujiang Bridge Engineering Co.,Ltd.,Jiujiang 332000,China)

机构地区：[1]中铁九桥工程有限公司,江西九江332000

出　　处：《世界桥梁》2018年第1期28-31,共4页World Bridges

摘　　要：沪通长江大桥主航道桥为主跨1 092m公铁两用斜拉桥,主桁采用3片桁片连接的"N"形桁,每个竖杆部位均设置横向联结系,桁片接头较多,母材材质品种多。主桁桁片采用3+1短线法,三桁同步总拼;采用多层多道焊接方式进行桁片焊接。总拼时,设置2个边桁胎架和1个中桁胎架;地模样板基准点布置完成后,采用吊垂线法控制上、下弦杆系统点与地模样板基准点的对应位置;以弦杆为基准定位竖杆、斜杆,完成整轮次杆件拼装定位。桁片焊接时,设置可移动防护装置,严格控制焊接顺序和焊接参数,进行多层多道焊接。桁片总拼制造验收结果表明,桁片焊后尺寸及线形满足要求,焊接变形得到控制,焊接收缩量设置合理。The main navigational channel bridge of Hutong Changjiang River Bridge is a rail-cum-road cable-stayed bridge with a main span of 1 092 m.The main truss adopts the N-shaped truss made from three truss blocks.Lateral bracings are set at the locations of each and all vertical members.A large number of joints are contained in the trusses and multiple types of base materials are used.The three truss blocks were simultaneously assembled by using the 3+1 short line matching method and were welded in layers and in stages.During the overall assembly,two side truss jigs and one central truss jig were installed.When the benchmark points of the ground mould sample were placed,the perpendicular drop method was used to control the corresponding positions of the systematic points of upper and lower chord and the benchmark points of the ground mould sample.The chords were taken as the benchmark to position the vertical members and diagonals,to finish the assembling position of the sub-members in an assembly circle.During the welding of the trusses,the movable protection devices were set,the welding sequence and parameters were strictly controlled during the multilayer and multistage welding.The results of the global assembly acceptance of the trusses show that the dimension and geometry of the trusses after welding meet the requirements,the welding deformation has been under control and the welding shrinkage amount set is reasonable.

关 键 词：公路铁路两用桥 斜拉桥 钢桁梁 短线法 同步总拼 焊接 施工技术 

分 类 号：U448.211[建筑科学—桥梁与隧道工程] U445.583[交通运输工程—道路与铁道工程]