炭质围岩地层三线大跨隧道出口段支护设计及变形控制技术  

Research on the Support Design and Deformation Control Technology of the Exit Section of a Three-Lane Long-Span Tunnel in the Carbonaceous Surrounding Rock

作　　者：罗胜利 丁文云 罗如平 LUO Shengli;DING Wenyun;LUO Ruping(China Railway Second Institute Kunming Survey and Design Research Institute Co.,Ltd.,Kunming 650500,China;School of Civil Engineering and Architecture,East China Jiaotong University,Nanchang 330013,China)

机构地区：[1]中铁二院昆明勘察设计研究院有限责任公司,云南昆明650500 [2]华东交通大学土木建筑学院,江西南昌330013

出　　处：《国防交通工程与技术》2023年第5期68-72,共5页Traffic Engineering and Technology for National Defence

摘　　要：以新建铁路玉溪至磨憨线王岗山隧道出口段为工程背景,通过分析炭质围岩地层中三线大跨隧道围岩及衬砌结构大变形情况及其产生原因,提出了优化隧道支护设计及施工方案,并通过现场实测资料验证了优化方案的可行性。分析表明:炭质围岩地层中三线大跨隧道,采用三台阶加临时仰拱工法施工会使围岩暴露时间过长、暴露范围过大,导致初期支护开裂、拱架扭曲变形严重;采用双侧壁导坑法、大管棚和小导管综合超前支护、二衬支护加强等措施能有效解决炭质围岩隧道开挖大变形难题。Taking the exit section of Wanggangshan Tunnel,located in the newly-built railway line from Yuxi to Mohan,as the engineering background,the large deformation characteristics and the causes of the surrounding rock and lining structure of the three-lane long-span tunnel in carbonaceous rock stratum were analyzed.The optimized tunnel support design and construction scheme were proposed and which was verified its feasibility by measurement data.The results show that:for the three-lane long-span tunnel in the carbonaceous rock formation,using the three-step and temporary inverted arch construction method makes the surrounding rock exposed for too long and the exposure range is too large,resulting in cracking of the initial support and serious distortion of the arch.The problem of large deformation of carbonaceous surrounding rock during tunnel excavation is effectively solved by adopting the double-sidewall pilot tunnel method,comprehensive advanced support of large pipe shed and small pipe,strengthening of secondary lining support and other measures.

关 键 词：隧道 炭质围岩 出口段 支护设计 变形控制 

分 类 号：U455.4[建筑科学—桥梁与隧道工程]