马鞍山长江公铁大桥主航道桥施工方案  

Construction Scheme of Main Navigation Channel Bridge of Maanshan Changjiang River Rail-cum-Road Bridge

作　　者：刘爱林[1,2] 沈大才 LIU Ailin;SHEN Dacai(China Railway Major Bridge Engineering Group Co.,Ltd.,Wuhan 430050,China;State Key Laboratory of Intelligent and Green Bridge Construction,Wuhan 430034,China)

机构地区：[1]中铁大桥局集团有限公司,湖北武汉430050 [2]桥梁智能与绿色建造全国重点实验室,湖北武汉430034

出　　处：《桥梁建设》2023年第6期10-17,共8页Bridge Construction

基　　金：中国中铁股份有限公司科技研究开发计划项目(2021-专项-03)。

摘　　要：马鞍山长江公铁大桥主航道桥为双主跨1120 m的三塔钢桁梁斜拉桥,桥塔基础采用∅4.0 m超大直径钻孔桩基础,桥塔为钢-混组合塔(上塔柱为钢结构,中、下塔柱为C60混凝土结构),钢桁梁采用两节间大节段全焊设计、制造。边塔钻孔桩基础施工采用吹沙筑岛形成钻孔平台,钻孔采用旋挖钻分级扩钻成孔,承台采用钢管桩+钢板桩组合围堰施工;中塔钻孔桩基础施工采用栈桥+水上钢平台,钻孔采用旋挖钻+回转钻组合接力成孔,承台采用矩形双壁钢套箱围堰施工,底节双壁钢套箱围堰采用水中漂浮连接法拼装。桥塔混凝土塔柱采用液压爬模施工,钢塔柱采用15000 t·m塔吊分块吊装;下横梁采用落地支架分层现浇。岸上和牛屯河边滩上钢桁梁节段采用“提升站+运梁栈桥+运梁台车”方案转运至1800 t架梁吊机起吊位置正下方由吊机起吊架设;边、辅跨间钢桁梁采用全顶推法架设,其余钢桁梁采用架梁吊机整节段悬臂架设;边(中)塔处设置抗风牛腿、Z3-Z4号塔间设置1座抗风临时墩,以保证主梁大悬臂架设过程中的抗风稳定;主跨跨中钢桁梁采用整节段合龙方案,先进行Z3-Z4号塔间主跨合龙,后进行Z4-Z5号塔间主跨合龙。The main navigation channel bridge of Maanshan Changjiang River Rail-cum-Road Bridge is a steel truss girder cable-stayed bridge with three pylons that create two main spans of 1120 m.Supported by 4 m-diameter bored piles,the pylons are steel-concrete composite structures comprised of steel upper columns and C60 intermediate and lower columns.Each and every two steel truss panels were welded to be a large segment to facilitate erection.In the construction of side pylon foundation,an artificial island was first made via sand blowing to create a platform,subsequently the rotary drilling rigs were used for borehole formation.The pile caps were cast in situ with the assistance of a composite cofferdam consisting of steel pipe piles and steel sheet piles.A trestle and a river steel platform were built for the construction of the foundation of the central pylon,and the rotary drilling rigs and the swing excavator were used together in borehole formation.The pile cap was cast in situ with a rectangular double-walled steel box cofferdam,the bottom lift of which were assembled by a floating connection method.The concrete pylon columns were cast using a hydraulic climbing formwork,while the steel pylon columns were installed segment by segment using a 15000 t·m-capacity tower crane.The lower crossbeam of the pylon was cast in situ on floor-standing scaffolds.The steel trusses over the banks and shoal area of the Niutun River were moved to the sites of the 1800 t-capacity cranes after being delivered through a lifting station,a trestle and delivery trolleys.The steel trusses in the side and auxiliary spans were incrementally launched,and the remaining steel trusses were cantilever-assembled segment-by-segment using deck cranes.To ensure the stability of the large-cantilever erection of the steel trusses,wind-resistant brackets were installed at the side and central pylons,and a wind-resistant temporary pier was added between pylons Z3 and Z4.The key segments in the midspan of the two main spans were integrally hoisted into

关 键 词：公路铁路两用桥 斜拉桥 桩基础 钢-混组合塔 钢桁梁 顶推法架设 悬臂架设 施工方案 

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]