赤壁长江公路大桥南岸滩桥移动模架双幅交汇过孔施工技术  

Techniques to Make Staggering Movement of Two Sets of Movable Scaffoldings During Construction of South Shoal-Crossing Section of Chibi Changjiang River Highway Bridge

作　　者：尹振君[1] 肖劼 YIN Zhen-jun;XIAO Jie(The Fifth Engineering Co.,Ltd.,China Railway Major Bridge Engineering Group,Jiujiang 332004,China)

机构地区：[1]中铁大桥局集团第五工程有限公司,江西九江332004

出　　处：《桥梁建设》2022年第3期140-145,共6页Bridge Construction

摘　　要：赤壁长江公路大桥南岸滩桥为7×(5×50)m预应力混凝土连续梁桥,主梁采用2套下行式移动模架施工。受地形条件的影响,移动模架施工时采用中间拼装、双幅交汇过孔方案,即拼装场地设置在滩桥中部,2套移动模架倒退走行至首孔箱梁处开始施工,在退回首孔箱梁时,2套移动模架通过大跨度下行式移动模架双幅交汇过孔技术完成交汇过孔。在交汇过孔过程中,通过墩旁托架不对称安装避免了左、右幅墩旁托架相互冲突;通过底模桁架旋转、翼模旋转完成不对称开模施工,避免了另一幅移动模架和窄缝现浇梁的影响;通过双向过孔施工技术解决了倒退至首孔箱梁再反向施工的难题。The south shoal-crossing section of the Chibi Changjiang River Highway Bridge consists of twin prestressed concrete continuous girder viaducts with seven units of 5×50 m each.The superstructures of the viaducts were constructed using two sets of underslung moving scaffoldings.To accommodate the terrain conditions,the two sets of movable scaffoldings were designed to be assembled at the central part of the viaducts,that is to say,the assembly platform was set at the central part of the viaducts,once taking shape,the two sets of scaffoldings walked backwards to the starter spans to carry out box girder casting.During construction,the two sets of scaffoldings were moved in a staggering manner to avoid collision,with an interval of two spans,and the pier-side brackets in the two viaducts were asymmetrically distributed for the same purpose.The base truss and flanges of each set of the movable scaffoldings could be rotated,if necessary,to minimize the disturbance to the work of the other set of movable scaffolding.In each casting cycle,the scaffoldings needed to move forward at a distance of five spans(from a start span to the end span of a continuous unit),and then to carry out casting backward,and the custom-made techniques ensured the smooth span-by-span forward and backward movement of the scaffoldings during construction.

关 键 词：连续梁桥 预应力混凝土梁 下行式移动模架 交汇过孔 不对称开模 墩旁托架 双向过孔 施工技术 

分 类 号：U448.215[建筑科学—桥梁与隧道工程] U445.463[交通运输工程—道路与铁道工程]