软岩大断面隧洞开挖支护施工技术  

Construction Technology for Excavation and Support of Large Section Tunnel in Soft Rock

作　　者：王松茂 WANG Songmao(Guangdong No.2 Hydropower Engineering Co.,Ltd.,Guangzhou 511340,China)

机构地区：[1]广东水电二局集团有限公司,广州511340

出　　处：《广东水利水电》2025年第4期74-79,96,共7页Guangdong Water Resources and Hydropower

摘　　要：环北部湾广东水资源配置工程合江支洞为软岩大断面隧洞,围岩自稳性低,开挖坍塌风险高,设计要求开挖与二衬同步推进,施工难度大。文章论述了对Ⅳ类、Ⅴ类围岩分别采用两台阶法开挖+仰拱开挖、环形开挖预留核心土法+仰拱开挖的组合施工方法,同时采用快速进行超前小导管支护、钢拱架与锚喷联合支护的施工方法和技术措施。结果表明,施工过程中围岩变形稳定可控。隧洞施工安全顺利完成,研究成果可为类似工程提供借鉴。The Hejiang Branch Tunnel of the Guangdong Water Resources Allocation Project in the Beibu Gulf is a soft rock large cross-section tunnel with low rock stability and high risk of excavation collapse.The design requires synchronous excavation and secondary lining,making construction difficult.This paper discusses the combined construction method of two step excavation+inverted arch excavation,circular excavation with reserved core soil method+inverted arch excavation for excavation of Class Ⅳ and Class Ⅴ surrounding rocks,as well as the construction method and technical measures for rapid advance small conduit support,steel arch and anchor spray joint support.During the construction process,the deformation of the surrounding rock is stable and controllable,and the tunnel construction is safely and smoothly completed,which can provide reference for similar engineering construction.

关 键 词：软弱围岩 大断面隧洞 台阶法开挖 环形开挖预留核心土法 仰拱开挖 联合支护 

分 类 号：TV554[水利工程—水利水电工程]