摘要
宜宾临港长江公铁大桥主桥为主跨522 m的公铁同层双塔双索面钢箱梁斜拉桥,主桥钢箱梁宽63.9 m、高5 m,节段最大重量519.6 t。钢箱梁采用分部件加工、节段整体制作、场内预拼装方案制造。南岸钢箱梁采用边跨顶推+中跨单悬臂施工;北岸钢箱梁采用边跨存梁+双悬臂施工;中跨合龙段采用配切+顶推合龙。采用钢箱梁顶板与底板单元两拼工艺、钢箱梁锚固块体多工序组拼、预设反变形量的长线法总拼等制造技术,有效解决了超宽钢箱梁焊接变形量大的问题,大大提高了钢箱梁制造精度;南岸边跨钢箱梁利用中跨侧来梁进行顶推施工,解决了边跨运梁、吊梁施工难的问题,且避免了占用既有道路;北岸边跨钢箱梁利用枯水期预先存梁,解决了浅滩区钢箱梁施工受季节性水文影响大的问题,为双悬臂施工提供了先决条件;中跨合龙段采用现场配切+顶推施工,实现主跨钢箱梁精确合龙。
The main bridge of Lingang Changjiang River Rail-cum-Road Bridge is a two-pylon cable-stayed bridge with a main span of 522 m.The stay cables are arranged in double cable planes.Carrying the road and rail traffic on the same deck,the superstructure that consists of steel box girders measures 63.9 m wide and 5 m deep,with the maximum girder segment weighing 519.6 t.The individually manufactured constituents of the steel box girders were assembled into integral segments in the factory,which were in turn transported to the bridge site for assembly.On the south bank,the steel box girders in the side and central spans were installed by the incremental launching and one-way cantilever assembly methods,respectively,while on the north bank,the girders in the side spans were kept in storage before the balanced cantilever assembly,and the key segments in the central span were match-cut and pushed into position to complete the closure of the superstructure.To effectively control the large welding deformation and improve the manufacturing accuracy of the extra wide steel box girders,multiple techniques were applied,including double-panel assembly of the top and bottom panels of steel box girders,multi-procedure assembly of anchor wedges in steel box girders,and the long-line match assembly with precambers.On the south bank,the steel box girders in the side spans were incrementally launched from the central span towards the bank,facilitating the delivery and hoisting of side spans and avoiding the occupation of service roads.On the north bank,the steel box girders in the side spans were stored at the bridge site in the dry season,to better address the hydrological conditions in the shoal zones and prepare for the subsequent balanced cantilever assembly.The key segments in the central span were match-cut and pushed into position to achieve the accurate closure of the main span.
作者
杨如刚
陈正
于志兵
陈博
化苏文
YANG Rugang;CHEN Zheng;YU Zhibing;CHEN Bo;HUA Suwen(Shudao Investment Group Co.,Ltd.,Chengdu 610041,China;Sichuan Road and Bridge(Group)Co.,Ltd.,Chengdu 610041,China;China Railway Baoji Bridge Group Co.,Ltd.,Baoji 721000,China)
出处
《桥梁建设》
EI
CSCD
北大核心
2024年第1期16-22,共7页
Bridge Construction
基金
四川省交通运输科技项目(2021-ZL-12)。
关键词
公路铁路两用桥
斜拉桥
钢箱梁
顶推施工
悬臂架设
存梁
合龙
施工技术
rail-cum-road bridge
cable-stayed bridge
steel box girder
incremental launching
cantilever assembly
girder storage
closure
construction technique
