基于摩擦力止推的沉管隧道最终接头关键技术创新与实践  

Innovation and Practice of Key Technologies for Immersed Tunnel Terminal Joint Based on Friction Antithrust

作　　者：曾波存 封江东 周兴涛 王聪[1,3] 孙晓伟 任耀谱[4] ZENG Bocun;FENG Jiangdong;ZHOU Xingtao;WANG Cong;SUN Xiaowei;REN Yaopu(CCCC Second Harbour Engineering Co.,Ltd.,Wuhan 430040,Hubei,China;School of Civil Engineering and Architecture,Hubei University of Arts and Science,Xiangyang 441053,Hubei,China;Key Laboratory of Large-span Bridge Construction Technology of Ministry of Communications,Wuhan 430040,Hubei,China;CCCC Highway Consultants Co.,Ltd.,Beijing 100088,China)

机构地区：[1]中交第二航务工程局有限公司,湖北武汉430040 [2]湖北文理学院土木工程与建筑学院,湖北襄阳441053 [3]长大桥梁建设施工技术交通行业重点试验室,湖北武汉430040 [4]中交公路规划设计院有限公司,北京100088

出　　处：《隧道建设（中英文）》2023年第5期847-855,共9页Tunnel Construction

基　　金：湖北省自然科学基金计划项目(2021CFB153);中国交通建设股份有限公司科技研发项目(2018-ZJKJ-17)。

摘　　要：为解决当前沉管隧道最终接头施工中存在的水下作业工序多、施工工艺复杂、水下止推结构质量检测难度大等难题,依托襄阳汉江沉管隧道工程,提出基于摩擦力止推的最终接头施工工艺。利用隧道管节与周边地层间的摩擦力及管节接头处安装临时限位结构的拉力,补偿干坞抽水过程中最终管节尾部所消散的水压力,确保隧道管节的安全稳定;并建立隧道管节总止推力与总推力的计算方法。研究结果表明:1)当管节顶部回填压重后,在E1/E2、E2/E3接头处设置临时精轧螺纹钢连接措施,可有效利用管节与周边砂卵石地层间的摩擦力,防止受压缩的Gina止水带回弹,确保单个及整体管节单元的安全稳定,无需在沉管隧道端部设置单独的止推结构;2)在干坞抽水及现浇隧道施工阶段,管节接头张合量及临时精轧螺纹钢轴力监测数据较为稳定,与计算结果基本一致,验证了所提出的基于摩擦力止推的沉管隧道最终接头技术是可行的。The existing terminal joint construction of an immersed tunnel is challenging due to multiple underwater operation procedures,complex construction technology,and difficult quality detection of underwater antithrust structure.To address these issues,a case study is conducted on the Hanjiang river immersed tunnel in Xiangyang,China,and a novel immersed tunnel terminal joint construction technique is proposed based on the concept of friction antithrust.This technique exploits the friction force between the tunnel elements and the surrounding stratum as well as the tension force of the temporary finish rolled steel bar installed at the element joints to compensate for the water pressure dissipated at the end of the final tunnel element,guaranteeing the safety and stability of the tunnel elements.Furthermore,the calculation methods for the total antithrust and thrust forces of the tunnel element are established.The research results reveal the following:(1)When the top of the tunnel elements is backfilled,the connection measure of setting up temporary finish rolled steel bars at the E1/E2 and E2/E3 joints is adopted,effectively exploiting the friction force between the tunnel elements and the surrounding sand-gravel strata,and preventing the compressed Gina water-stop from bouncing back;thus,the safety and stability of tunnel elements can be ensured and a separate antithrust structure need not be set at the end of the immersed tunnel.(2)During dry dock pumping and cast-in-place tunnel construction,monitoring data of the opening and closing amount of tunnel element joints and the axial force of the temporary finish rolled steel bars are relatively stable and consistent with the calculation results;furthermore,the feasibility of the proposed terminal joint construction technique for the immersed tunnels based on friction antithrust is validated.

关 键 词：沉管隧道 最终接头 摩擦力止推 临时精轧螺纹钢 

分 类 号：U455[建筑科学—桥梁与隧道工程]