极高地应力软岩隧道贯通段变形控制方案研究——以兰渝铁路木寨岭隧道为例

Study of Deformation Control Scheme of Breakthrough Section of Soft Rock Muzhailing Tunnel on Lanzhou-Chongqing Railway with Extremely High Ground Stress

为了解决极高地应力软岩隧道越岭核心贯通段大变形控制难题,以兰渝铁路木寨岭隧道施工为例,通过现场试验和数据分析,得到如下结论:1)确定了越岭核心贯通段的长度;2)提出了越岭核心贯通段"4层初期支护结构+径向注浆+长锚杆+长锚索"综合变形控制方案;3)得到了贯通段多层初期支护结构变形控制效果;4)说明贯通段施工及变形控制方案可行。

The deformation control of the core breakthrough section of soft rock mountain-crossing tunnel with extremely high ground stress is very difficult. The field test is carried out and the data collected are analyzed by taking Muzhailing Tunnel on Lanzhou-Chongqing Railway for example. Some conclusions are drawn as follows ： 1 ） The length of the core breakthrough section crossing mountain is determined. 2） The comprehensive deformation control scheme of ＂four-layer tunnel primary support structure ＋ radial grouting ＋ long anchor bolt ＋ long anchor rope＂ for core breakthrough section crossing mountain is proposed. 3） The deformation control effect of multilayer support structure of the breakthrough section is good. 4） The construction scheme and deformation control scheme for breakthrough section are rational.