摘要
宜昌香溪河大桥为主跨470m的混合梁斜拉桥,桥位处于三峡水域,深水落差大、地质复杂,经比选采用深水桥梁基础快速施工技术。该技术采用“先平台后围堰”施工顺序,首先设置重载高位平台,在深水、大倾斜河床条件下完成平台的精确定位与体系转换,提前进入桩基施工;然后利用环形轨道系统,进行深水套箱围堰拼装与钻孔桩施工的同步作业。针对大倾角河床面特点,在围堰底部设置挡板,依次进行底角回填堵漏、河床找平及围堰封底,保证了围堰的稳定与结构安全。
The Xiangxi River Bridge in Yichang is a hybrid girder cable-stayed bridge with a main span of 470 m.The bridge is located in the Three Gorges water area,where the water is deep,the water level difference is big and the geological condition is complex.By the schemes comparison,a rapid construction technique that is feasible to bridge foundations in deep water is chosen.The piles were constructed before the cofferdam.First,a high-level platform that was able to carry heavy loads was erected.Although the water was deep and the riverbed was inclined severely,the precise positioning of the platform and systematic transformation were completed,and the construction of the pile foundation was started ahead of the schedule.Then,a circular rail system was used to carry out the assembly of the high and big steel box cofferdam,which ensured the parallel construction of the bored piles.By considering the special characteristic of the severely inclined riverbed,retaining plates were added to the bottom of the cofferdam,then,the edges of the cofferdam were blocked to prevent leakage,the riverbed was leveled and the base of the cofferdam was sealed,to ensure the stability and structural safety of the cofferdam.
作者
祝良红
刘旭
ZHU Liang-hong;LIU Xu(The Seventh Engineering Co.,Ltd.,China Railway Major Bridge Engineering Group,Wuhan 430056,China)
出处
《世界桥梁》
北大核心
2019年第5期33-38,共6页
World Bridges
关键词
斜拉桥
三峡库区
深水基础
套箱围堰
钻孔桩
先平台后围堰
体系转换
封底
cable-stayed bridge
Three Gorges area
deepwater foundation
steel box cofferdam
bored pile
to construct the piles before the cofferdam
systematic transformation
base sealing
