高地应力软岩地层敞开式TBM法隧洞围岩变形控制技术——以香炉山隧洞为例  

Surrounding Rock Deformation Control Technology for Tunnels Constructed Using Open Tunnel Boring Machines in Soft Rock Strata With High Geostress:A Case Study of Xianglushan Tunnel

作　　者：王斌 杨延栋 周建军 李凤远 徐海峰 刘超尹 WANG Bin;YANG Yandong;ZHOU Jianjun;LI Fengyuan;XU Haifeng;LIU Chaoyin(China Railway Tunnel Group Co.,Ltd.,Guangzhou 511458,Guangdong,China;China Railway Tunnel Stock Co.,Ltd.,Zhengzhou 450001,Henan,China;State Key Laboratory of Shield Machine and Boring Technology,Zhengzhou 450001,Henan,China)

机构地区：[1]中铁隧道局集团有限公司,广东广州511458 [2]中铁隧道股份有限公司,河南郑州450001 [3]盾构及掘进技术国家重点实验室,河南郑州450001

出　　处：《隧道建设（中英文）》2024年第2期341-348,共8页Tunnel Construction

基　　金：河南省科技攻关计划(232102320242,232102320052);中国中铁科研开发计划(CZ02-专项-03,2020-重大专项-04,2021-重点-12);中铁隧道局集团科技创新计划(隧研合2020-18)。

摘　　要：为解决敞开式TBM在滇西地区高地应力软岩地层施工中遭遇围岩大变形而导致的支护破坏、设备频繁被卡、隧洞侵限等工程难题,通过分析围岩允许变形量与变形规律,提出围岩控制时空原则:有效初期支护施作时间为开挖后15 d内、空间位置为距掌子面30 m范围内,TBM掘进日进尺不低于2 m/d。通过不同类型的支护结构现场试验,得出控制围岩变形的有效措施为预应力长锚索主动控制变形、灌混凝土箱体H型钢拱架被动强支撑。另通过滇中引水香炉山隧洞敞开式TBM施工实践,开发出“掌子面位置刀盘扩挖预留允许变形量、围岩出护盾灌混凝土箱体拱架被动强支撑、隧洞上半圆前置式自动化喷混凝土早封闭、预应力长锚索主动控制深层围岩变形、隧洞底部自进式锚杆后补强”等围岩变形有效控制技术。The implementation of an open tunnel boring machine(TBM)for construction within high-geostress soft rock formations in western Yunnan,China,encounters various challenges,such as support failures,frequent equipment jamming,and tunnel intrusions,due to large deformation of surrounding rocks.Consequently,an analysis of the permissible deformation amount and deformation pattern of the surrounding rocks is conducted to propose spatiotemporal principles for controlling the surrounding rocks.These principles include initiating primary support construction within 15 days after excavation,spatial positioning within 30 m from the excavation face,and requiring a minimum daily TBM excavation rate of 2 m.On-site tests on different types of support structures reveal that prestressed long anchor cables and H-shaped steel arches filled with concrete can effectively control the surrounding rock deformation.Several effective technologies have been developed for controlling surrounding rock deformation through open TBM construction practices at the Xianglushan tunnel within the central Yunnan water diversion project.These technologies encompass reserved allowable deformation during cutterhead expansion excavation at the face position,passive strong support of the surrounding rock shield pouring concrete box arch frames,automatic early sealing of the upper half circle of the tunnel with preinstalled shotcrete,active control of deep surrounding rock deformation using prestressed long anchor cables,and reinforcement of the bottom of the tunnel with self-advancing anchor bolts.

关 键 词：软岩大变形 围岩变形控制 高地应力 引水隧洞 岩石隧道掘进机 

分 类 号：U45[建筑科学—桥梁与隧道工程]