G3铜陵长江公铁大桥U形无内支撑预应力锚索组合围堰设计  

Design of Prestressed-Cable-Anchored,U-Shaped Composite Cofferdam Without Interior Supports for Tongling Changjiang River Rail-cum-Road Bridge Carrying a Section of G3 Expressway

作　　者：何明辉[1] HE Minghui(China Railway Major Bridge Engineering Group Co.,Ltd.,Wuhan 430050,China)

机构地区：[1]中铁大桥局集团有限公司,湖北武汉430050

出　　处：《世界桥梁》2025年第2期15-20,共6页World Bridges

基　　金：中铁大桥局集团有限公司科学技术研究与开发项目(2022-03-重大)。

摘　　要：G3铜陵长江公铁大桥主桥采用(127.5+131+988+131+127.5)m斜拉-悬索协作体系桥。4号桥塔墩矩形-哑铃形承台平面尺寸为88.6 m×42.5 m,厚7.0 m,平均埋置深度约10 m。墩位处紧邻深切大崖壁,河床基岩基本裸露,综合考虑墩位处地形、地质等条件,采用靴形断面的U形无内支撑+预应力锚索组合形式的双壁钢围堰。围堰平面设计为129 m×81 m的U形开口结构,围堰上游侧长81.1 m,江心侧长129.0 m,下游侧长52.0 m,围堰顶高程+14.5 m,底高程随河床高程变化。为方便围堰制造与安装,围堰平面分为A~K共计11个节段,B~J钢结构节段竖向分为双壁侧板和单壁侧板,通过扩大基础、预应力锚索将围堰锚固在河床面上,A、K混凝土节段与钢结构节段和山体连接。采用有限元软件对围堰建模计算,围堰整体抗倾覆、抗滑移性能、受力及变形均满足要求。The main bridge of Tongling Changjiang River Rail-cum-Road Bridge carrying a section of the G3 Expressway is a hybrid cable-stayed suspension bridge with span configuration of 127.5,131,988,131,and 127.5 m.The pylon pier No.4 rests on a dumbbell-like pile cap(featuring two identical rectangular"masses")that measures 88.6 m by 42.5 m,7.0 m in depth,with an average length of 10 m embedded in the bedrock.Comprehensively considering the topological and geological conditions at the pylon site,specifically the challenges imposed by the sheer cliff and exposed river bedrock,a U-shaped composite cofferdam that has no interior supports was proposed.The cofferdam measures 129 m by 81 m in plan,with lengths of 81.1 m,129.0 m,and 52.0 m on the upstream,river center and downstream sides,respectively.The top of the cofferdam is at an elevation of+14.5 m,while the elevation of the bottom varies along with the rolling riverbed.To facilitate the manufacture and assembly,the cofferdam was divided into sections in plan,numbered A to K11,among which the steel sections B to J were zoned by the categories of double-wall plates and single-wall plates.The cofferdam was anchored to the riverbed via a spread foundation and prestressed cables,making it a special boot-shaped composite foundation.The concrete sections A and K as well as all the steel sections were connected with the hills.The numerical simulation indicated that the overall anti-overturning and anti-slipping capacities as well as the mechanical property and deformation of the cofferdam met the requirements.

关 键 词：斜拉-悬索协作体系桥 桥塔墩 组合围堰 无内支撑 预应力锚索 扩大基础 结构设计 

分 类 号：U445.556[建筑科学—桥梁与隧道工程] U442.5[交通运输工程—道路与铁道工程]