裸巖區深水基礎先堰后樁建造技術研究*

劉曉敏，張強，李飛，楊金勇

(中國建筑第六工程局有限公司，天津 300451)

［摘要］ 以清溪口渠江特大橋5號主塔橋墩深水基礎為背景，研究一種滿足裸巖區先堰后樁的建造技術，包括大型鋼圍堰氣囊下水、浮運、定位、下沉和鉆孔平臺搭設與鉆孔等關鍵工序。運用有限元軟件對雙壁鋼圍堰在各不利工況下的受力性能進行分析，結果表明：雙壁鋼圍堰的整體強度、剛度和穩定性均滿足施工要求；鋼圍堰封底混凝土的厚度以及圍堰的浮游穩定性也滿足施工要求。

［關鍵詞］橋梁工程；基礎；雙壁鋼圍堰；穩定性；受力分析

［中圖分類號］TU753  ［文獻標識碼］A          ［文章編號］1002-8498(2021)07-0031-04

Study on Construction Technology of Weir First and Pile Later for Deep Water Foundation in Bare Rock Area

LIU Xiaomin, ZHANG Qiang, LI Fei, YANG Jinyong

(China Construction Sixth Engineering Division Co., Ltd.，Tianjin 300451, China)

Abstract: Based on the deep water foundation of the main tower pier of Qingxikou Qujiang bridge, a construction technology of weir first and pile later in bare rock area is studied, including key processes of large steel cofferdam launching, floating, positioning, sinking, drilling platform erection and drilling. The finite element software is used to analyze the mechanical performance of double wall steel cofferdam under various unfavorable working conditions. The results show that the overall strength, stiffness and stability of the double wall steel cofferdam meet the construction requirements. The thickness of the bottom concrete of the steel cofferdam and the floating stability of the cofferdam can also meet the construction requirements.

Keywords:bridges; foundations; double wall steel cofferdam; stability; force analysis

*中建股份科研課題(CSCEC-2015-Z-06)

［作者簡介］ 劉曉敏，博士，高級工程師，E-mail：286237078@qq.com