摘要
沌口长江公路大桥为主跨760m的双塔双索面钢箱梁斜拉桥,其中南岸4号桥塔墩位于长江深泓区,该区域覆盖层薄,局部基岩裸露,且岩面倾斜,基础施工采用先围堰后桩基的施工方案。围堰为双壁钢套箱围堰结构,平面呈八边形,长55.3m,宽29.1m,高23.9m。结合现场水文地质条件,钢围堰采用单定位船定位、注水下沉;钢围堰局部着床后采用麻袋混凝土和钢支墩进行支垫;钢围堰调平后进行刃脚封堵和外防护施工;钢护筒沉放、临时固定后进行底口封堵;围堰封底分2次进行,达到设计强度后开始桩基施工。
The Zhuankou Changjiang River Highway Bridge is a steel box girder cable-stayed bridge.The bridge has two pylons,creating a main span of 760 m.The stay cables are fanned out in double cable planes.The No.4 pylon pier on the south bank is located in the deep water area of the Changjiang River,where the overburden is thin,with locally-exposed bed rocks,and the rock surface is inclined.Considering these conditions,the foundation was constructed by way of using steel cofferdam to support the construction of piles.The cofferdam is the octagonal double-walled steel cofferdam,with the dimension of 55.3 mby 29.1 m,and 23.9 min height.Counting the hydrological and geological conditions at the bridge site,the steel cofferdam was positioned by the single positioning vessel and sunk by pouring water.When locally landed on the river bed,the steel cofferdam was propped and balanced by bagged concrete and steel supporting piers.Then,the steel cofferdam was levelled,the cutting edges were blocked to prevent leaking and the construction of external protections began.Once the steel casings were sunk and guided into position,and temporarily fixed,the base sealing of the steel cofferdam started,which consisted of two times of sealing operation.When the tremie seal concrete in the cofferdam reached the design strength,the pile construction began.
作者
张延河
ZHANG Yan-he(CCCC Second Harbor Engineering Co.,Ltd.,Wuhan 430040,China)
出处
《世界桥梁》
北大核心
2019年第2期28-32,共5页
World Bridges
关键词
斜拉桥
深水基础
双壁钢套箱围堰
浅覆盖层
岩面倾斜
施工技术
cable-stayed bridge
deep water foundation
double-walled suspended steel box cofferdam
shallow overburden layer
inclined rock surface
construction technique
作者简介
张延河(1978-),男,高级工程师,2001年毕业于长春工程学院道路与桥梁专业,工学学士(E-mail:271507617@qq.com)。
