高山峡谷独塔钢-混混合梁斜拉桥钢箱梁架设关键技术  

Key Erection Techniques for Steel Box Girders of a Single-Pylon,Steel-Concrete Hybrid Girder Cable-Stayed Bridge Crossing a Valley in Mountainous Area

作　　者：陈云锋 CHEN Yunfeng(The First Engineering Co.,Ltd.,CCCC Third Highway Engineering Co.,Ltd.,Beijing 100012,China)

机构地区：[1]中交三公局第一工程有限公司,北京100012

出　　处：《世界桥梁》2024年第4期42-47,共6页World Bridges

摘　　要：昭通市巧家县金沙江特大桥主桥为(340+72+48+32) m钢-混混合梁独塔斜拉桥,中跨采用PK钢箱梁,高3.5 m,全宽32.3 m。该桥位于高山峡谷区,中跨钢箱梁梁段无法通过航运运输,且峡谷区施工便道狭窄,钢箱梁运输难度大,钢箱梁采用厂内分块匹配预制及现场边跨梁面组拼、后方喂梁悬臂架设的总体施工方案。钢箱梁通过板单元件现场拼装总成,采用“3+1”匹配拼装方式进行钢箱梁整节段线形控制,采用110 t自行走式平板车分块运输大吨位钢箱梁,实现高山峡谷区大坡度狭窄便道条件下钢箱梁的运输;在混凝土桥面拼装钢箱梁,通过运梁小车将钢箱梁运输至架桥机位置,提高混凝土桥面钢箱梁拼装及运输效率;采用斜拉桥后方喂梁-步履式大吨位悬臂架桥机,通过设计起重天车、支撑系统、锚固装置以及纵移系统等结构,完成钢箱梁后方喂梁、转体、拼装等工序,实现高山峡谷区斜拉桥施工。The main bridge of Jinshajiang River Bridge in Qiaojia County,Zhaotong City is a single-pylon cable-stayed bridge with four spans of 340,72,48 and 32 m.Measured 32.3 m in full width,the superstructure in the 340 m-long span consists of 3.5 m-deep steel box girders of PK cross-section that act compositely with the overlaid precast concrete panels.The bridge crosses a valley in the mountainous area,the steel box girder segments could not be shipped,or transported to the destination via the narrow construction accesses in the valley,and a scheme to prefabricate the plates of the girders and assembly the plates to form steel box girders on the previously installed concrete box girders in the side spans was selected.The prefabricated plates of the steel box girders were assembled at the bridge site,and the geometrical shape of the entire steel box girder segment was brought under control in a"3+1"match-assembly manner.The steel box girders were delivered segment by segment using the specialist 100 t-capacity self-propelled flatbed trucks,to achieve the transportation of steel box girders through the large-gradient and narrow accesses in the mountainous area.The steel box girder segments were assembled on the concrete girders in the side spans and delivered to the locations of the gantry cranes,to improve the assembly and transportation efficiency.The large-tonnage self-launching gantry crane allowing girder feeding from the back of the cable-stayed bridge was developed,and the feeding,rotation,and assembly of the steel box girders were completed with the assistance of the trolley,supporting system,anchor devices and longitudinal moving system.

关 键 词：斜拉桥 钢-混混合梁 钢箱梁 高山峡谷区 “3+1”匹配拼装 分块预制 架设技术 

分 类 号：U448.213[建筑科学—桥梁与隧道工程] U445.46[交通运输工程—道路与铁道工程]