深水卵石覆盖层超深双壁钢围堰下沉施工技术  

Sinking Construction Technology of Ultra⁃deep Double⁃wall Steel Cofferdam in Deep⁃water Pebble⁃covered Layer

作　　者：罗鹏 严朝跃 袁荣轩 LUO Peng;YAN Chaoyue;YUAN Rongxuan(Road&Bridge International Co.,Ltd.,Beijing100027,China;Road&Bridge East China Engineering Co.,Ltd.,Shanghai201203,China)

机构地区：[1]中交路桥建设有限公司,北京100027 [2]中交路桥华东工程有限公司,上海201203

出　　处：《施工技术(中英文)》2025年第6期128-133,共6页Construction Technology

基　　金：中交路桥建设有限公司科技研发项目:卵石地层深水深埋承台施工技术研究(ZJLJ⁃2024⁃12)。

摘　　要：新建益阳—常德高速公路扩容工程沅水特大桥主桥8,9号主墩承台埋入河床冲刷线以下,采用超深大直径双壁钢围堰进行施工,围堰需沉入河床约155m深;根据地质、水文等因素设计了“气举不排水抽砂”法围堰内抽砂方案,建立了一套可行的抽砂系统设计方法,提出采用“倒锅底”吸泥工艺使围堰快速下沉就位再形成“大锅底”状施工技术,提高了施工工效,保护了河道生态环境。抽砂下沉过程通过监测围堰顶面高差、河床抽砂状态和调整导向限位系统进行下沉姿态调整,控制了大斜面河床偏压对围堰造成的影响,设计环形清洗器等工具对钢护筒钢混结合面进行清洗,对钢护筒局部加深除渣,确保了围堰施工质量,从而安全、优质、高效地完成超深围堰施工。No.8 and No.9 piers of the main bridge of Yuan River Grand Bridge in Yiyang⁃Changde Expressway expansion project are embedded below the riverbed scouring line.An ultra⁃deep and large⁃diameter double⁃wall steel cofferdam is used,which needs to be sunk into the riverbed to a depth of approximately 155 meters.Based on geological and hydrological factors,“air⁃lift non⁃draining sand extraction”method is designed for the sand extraction inside the cofferdam,establishing a feasible sand extraction system design method.The“inverted pot bottom”mud suction process is proposed to quickly sink the cofferdam into position and form a“large pot bottom”construction technique,which improves construction efficiency and protects the river ecological environment.During the sand extraction and sinking process,the elevation difference of the cofferdam top surface is monitored,the sand extraction state of the riverbed is observed,and the guiding and limiting system is adjusted to control the impact of the large inclined riverbed bias pressure on the cofferdam.Ring cleaning devices are designed to clean the steel⁃concrete interface of the steel casing,and local deepening and slag removal of the steel casing are performed to ensure the construction quality of the cofferdam,which ensure the safe,high⁃quality,and efficient completion of the ultra⁃deep cofferdam construction.

关 键 词：桥梁 围堰 卵石覆盖层 气举抽砂 偏沉 施工技术 

分 类 号：U445[建筑科学—桥梁与隧道工程]