摘要
宜昌香溪河大桥为主跨470m双塔双索面混合梁斜拉桥,大桥主梁采用(48+48)m预应力混凝土梁+(78+470+78)m钢-混结合梁+(48+48)m预应力混凝土梁。针对该桥桥址处水位落差及风荷载较大情况,制定施工方案为:首先在边墩及辅助墩旁设置"框架式立柱+桁架式主梁"现浇支架结构,利用该结构按"纵向分段、水平分层"方式浇筑两岸48m跨预应力混凝土梁;随后在该混凝土梁上拼装架梁吊机,利用架梁吊机在临时支墩上面向主跨方向原位拼装78m跨钢-混结合梁;再采用单悬臂架设法拼装470m主跨侧钢-混结合梁;最后采用主动合龙方式进行主跨合龙。
The Xiangxi River Bridge in Yichang is a two-pylon hybrid girder cable-stayed bridge with a main span of 470 m.The stay cables are fanned out in double cable planes.The superstructure of the bridge consists of a prestressed concrete part with two equal spans of 48 m,a steel-concrete composite part with three spans of 78,470 and 78 m,and another prestressed concrete part with two equal spans of 48 m.The large water level difference and heavy wind loads at the bridge site make the original main girder construction scheme difficult to be implemented.To resolve this issue,the original construction scheme was optimized.First,the scaffoldings for in-situ casting formed of framed columns and truss-type main beams were installed beside the side and auxiliary piers,on which the prestressed concrete girders in the 48 m-long spans on the two river banks were cast in sections longitudinally and in layers horizontally.Second,the girder erection crane was installed on the concrete girder and used to assemble the 78 m-span steel-concrete composite girder on the auxiliary piers towards the main span.Then,the 470 m-span steelconcrete composite girder were installed by the single-cantilever method.Finally,the main girder was closed by way of active closure.
作者
吕磊
LYU Lei(China Railway Major Bridge Engineering Group Co.,Ltd.,Wuhan 430050,China)
出处
《世界桥梁》
北大核心
2020年第5期11-15,共5页
World Bridges
关键词
斜拉桥
钢-混结合梁
现浇支架
悬臂架设
合龙
施工方案
设计
cable-stayed bridge
steel-concrete composite girder
scaffoldings for in-situ casting
cantilever erection
closure
construction scheme
design
作者简介
吕磊(1986-),男,高级工程师,2008年毕业于重庆交通大学桥梁工程专业,工学学士(E-mail:383319058@qq.com)。
