超大埋深软岩隧道大变形机理及控制技术研究——以滇藏铁路丽香线哈巴雪山隧道为例  

Mechanism and Control of Large Deformations in Super-Deep Soft Rock Tunnels:A Case Study of Haba Snow Mountain Tunnel on Lijiang-Shangri-la Line of Yunnan-Xizang Railway

作　　者：谭忠盛[1] 赵金鹏 张宝瑾 TAN Zhongsheng;ZHAO Jinpeng;ZHANG Baojin(School of Civil Engineering,Beijing Jiaotong University,Beijing 100044,China;School of Civil Engineering,Tsinghua University,Beijing 100084,China)

机构地区：[1]北京交通大学土木建筑工程学院,北京100044 [2]清华大学土木水利学院,北京100084

出　　处：《隧道建设(中英文)》2024年第12期2307-2315,共9页Tunnel Construction

基　　金：国家自然科学基金项目(52408425)。

摘　　要：为解决超大埋深软岩隧道工程中,由于地应力高围岩软弱而产生的严重大变形、初期支护频繁拆换等问题,以丽香铁路哈巴雪山隧道工程为例,研究超大埋深软岩隧道大变形机理及控制技术,在分析超大埋深隧道大变形特征基础上,揭示隧道大变形机理,提出“超前应力释放+长短锚杆结合+强注浆+多层支护”的大变形隧道控制技术。哈巴雪山隧道大变形特征主要体现在掌子面易失稳、支护变形速率快、变形量大及结构破坏严重。通过采取控制措施,哈巴雪山隧道大变形现象得到了有效控制,实测表明隧道掌子面挤出变形减小60%以上,隧道变形量减小40%以上,且结构受力显著减小,围岩压力及接触压力均小于结构设计荷载(按1.0 MPa设计)。Super-deep soft rock tunnels are prone to extensive deformations owing to high in-situ stresses and the presence of soft surrounding rock,often necessitating frequent replacement of primary supports.The authors focus on the Haba Snow Mountain tunnel project on the Lijiang-Shangri-la railway.Specifically,the characteristics,mechanisms,and control techniques of large deformations in deep soft rock tunnels are examined.The large deformation characteristics of the selected tunnel are analyzed,and the mechanisms underlying these deformations are elucidated.A control technique involving advance stress relief,a combination of long and short anchor bolts,intensive grouting,and multi-layered support is proposed.Large deformations in the Haba Snow Mountain tunnel primarily manifest in the form of tunnel face instability,a rapid rate of support deformation,large deformation amplitudes,and severe structural damage.Implementing the proposed control measures effectively controls these large deformation phenomena.Measurement results indicate the following:The extrusion deformation of the tunnel face drops by over 60%,the overall tunnel deformation declines by over 40%,structural stress is considerably reduced,and the surrounding rock and contact pressures are lower than the structural design load of 1.0 MPa.

关 键 词：铁路隧道 软弱围岩 隧道大变形 变形特性 控制技术 

分 类 号：U45[建筑科学—桥梁与隧道工程]