秭归长江公路大桥主桥施工关键技术  

Key Construction Techniques for Main Bridge of Zigui Changjiang River Highway Bridge

作　　者：许鑫 蒋本俊[2] 陈开桥 XU Xin;JIANG Ben-jun;CHEN Kai-qiao(The Seventh Engineering Co.,Ltd.,China Railway Major Bridge Engineering Group,Wuhan 430056,China;China Railway Major Bride Engineering Group Co.,Ltd.,Wuhan 430050,China)

机构地区：[1]中铁大桥局第七工程有限公司,湖北武汉430056 [2]中铁大桥局集团有限公司,湖北武汉430050

出　　处：《世界桥梁》2023年第S01期55-62,共8页World Bridges

基　　金：湖北省交通运输厅科技项目(2016-600-2-3)。

摘　　要：秭归长江公路大桥主桥为计算跨径519 m的中承式钢桁架全推力无铰拱桥,拱座采用明挖扩大基础,主拱采用变高度双片桁架,主梁采用钢-混凝土结合梁。针对该桥施工场地狭小,地质、水文及风场条件复杂等情况,拱座采用边坡分级开挖与综合防护技术施工;缆索吊机采用扣缆塔基础与桥墩基础“永临结合”设计,通过采用桩基“钢护筒+柔性垫层”减摩阻技术及综合监测技术,保证了大跨度重型缆索吊机作业安全;钢桁拱采用斜拉扣挂法架设,主拱桁片式吊装、无铰拱快速精确合龙;拱上钢立柱采用立式预拼安装技术;主梁施工采用钢梁先整节段间隔架设再跨间散拼、混凝土桥面板水运提升技术。成桥后主拱线形及内力满足要求。The main bridge of Zigui Changjiang River Highway Bridge is a full-thrust half-through arch bridge with a calculated span length of 519 m.The arch ring,without articulation,consists of dual truss ribs of constant heights.The deck system is composed of steel girders acting compositely with the overlaid concrete slabs.Limited by the construction space,geological,hydrological and wind field conditions,during the arch seat construction,the slopes of the hill were excavated by the bench cut method,with comprehensive protection.For the cableway crane system,the tower foundation is a temporary structure,but could be transformed to be permanent pier foundation.By the combined utilization of steel casings and flexible blinding layer,the friction resistances of the foundation piles were reduced.With a comprehensive monitoring system,the long-span cableway crane system worked safely during construction.The arch ring was erected by the cableway crane system,panel by panel,and the arch without articulation was rapidly and accurately closed.The steel spandrel columns were preassembled vertically.For the deck system construction,the steel girder segments were erected into position,leaving a gap between two segments,then these gaps were filled via on-site assembly of individual components.The prefabricated concrete slabs were shipped to site and hoisted into position.The arch ring alignment and internal forces after completion of the bridge met the requirements.

关 键 词：钢桁架拱桥 拱座 主拱 钢-混凝土结合梁 缆索吊机 斜拉扣挂法 施工技术 

分 类 号：U448.224[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]