锦屏TBM组装洞特大断面空间交错施工技术

Staggered Construction Technology for a TBM Assembly Cavern with Large Section in the Jingping Hydropower Station

锦屏二级水电站3#引水隧洞TBM组装洞，是作为直径12．4m的TBM进行洞内组装面设计施工的、特大断面地下洞室。为克服断面特大、工期紧张等压力，研究了TBM组装洞特大断面分四层共十步的空间交错开挖方法及顺序，确定了适合于上述条件的各层间施工“顶层先行，导洞并举，多层平行，矿体交叉”以及同层“部分前行，余部跟进，支护紧随”的方法和作业顺序。文章简述了特大断面空面交错施工技术在锦屏特大断山TBM组装洞的技术应用。

The design of the No.3 diversion tunnel of the Jinping 11 hydropower station involved the assembly of a TBM with a diameter of 12.4m. The staggered construction consequence, which divided into 4 layers with ten steps to- tal, was adopted because of a large section and tight construction schedule. This method is characterized by advance crown exaction, a simultaneous pilot tunnel, parallel construction, and local advance excavation followed by immedi- ate support. This paper introduces the application of this technique to the construction of the Jingping hydropower sta- tion