超深水裸露陡坡基岩桩基施工浮动平台与固定平台结合方案的应用  

Application of Combination Scheme of Floating Platform and Fixed Platform for Exposed Steep Slope Bedrock Pile Foundation Construction in Ultra Deep Water

作　　者：徐小祥[1] 王彬[1] 朱晨鹤 XU Xiaoxiang;WANG Bin;ZHU Chenhe(Railway Combat Pontoon Bridge,Qihe 251100,China)

机构地区：[1]铁道战备舟桥处,山东齐河251100

出　　处：《国防交通工程与技术》2022年第4期59-64,共6页Traffic Engineering and Technology for National Defence

摘　　要：超深水裸露基岩河床条件下进行高桩承台桥梁基础施工时,一般采用浮式平台或者固定平台先进行钻孔桩基础施工,然后采用钢吊箱进行高桩承台施工;但在水深60 m以上的超深水和45°陡坡裸露花岗岩河床这种极端环境下进行钻孔桩施工时,单独采用某种方式施工难度极大。福建永定公路龙湖大桥施工针对困难工况,采用浮式平台和固定平台相结合的施工方式,即先依托浮式平台施工定位锚固桩,定位锚固桩以新型伸缩式水下连接系保证固定平台的安全稳定,利用固定平台进行主桥桩基施工。施工方案有效解决了超深水陡坡裸露基岩钻孔桩施工中出现的护筒滑移、偏位、跟进锚固困难等一系列技术难题,经济效益和社会效益良好。When the bridge foundation with high pile cap is constructed under the condition of exposed bedrock riverbed in ultra deep water,the floating platform or fixed platform is generally used for the construction of bored pile foundation first,and then the steel hanging box is used for the construction of high pile cap.However,when the bored pile construction is carried out in the extreme environment of ultra deep water with depth of more than 60 m and exposed granite riverbed with a steep slope of 45°,it is very difficult to adopt a certain method alone.For the construction of Longhu bridge on Yongding highway in Fujian province,the combination of floating platform and fixed platform is adopted for the construction of difficult working conditions,that is,the positioning anchor pile is constructed by relying on the floating platform,the positioning anchor pile ensures the safety and stability of the fixed platform with a new telescopic underwater connection system,and the fixed platform is used for the pile foundation construction of the main bridge.The construction scheme effectively solves a series of technical problems in the construction of bored pile with exposed bedrock on ultra deep water steep slope,such as pile casing slip,deviation and difficult follow-up anchorage,which has good economic and social benefits.

关 键 词：超深水陡坡裸岩 浮式平台 定位锚固桩 钢护筒 

分 类 号：U443.154[建筑科学—桥梁与隧道工程]