摘要
针对高应力软岩地层中时常发生的隧道塌方事故,以某铁路隧道Ⅳ级较软围岩洞段为研究对象,在隧道工程地质条件与地应力测试分析结果的基础上,对该隧道进行有限元分析,从不同角度对开挖方案进行优化,并在优选方案的基础上对锚杆加固效果进行了研究。研究表明:(1)开挖进尺越大,开挖扰动越大,围岩的变形位移量越大;(2)采用预留核心土法比采用全断面法和三步台阶法更有利于隧道稳定;(3)锚杆加固法在高应力软弱围岩中具有较好的效果。研究结果为隧道的开挖稳定性及安全支护提供参考,并对类似高应力软岩隧道的分析提供借鉴。
In view of the frequent occurrence of tunnel collapse accident in soft rock stratum with high stress,this paper takes class IV soft wall rock segment of one railway tunnel as the research object. Based on the analysis results of the engineering geological condition and in-situ stress test,the finite element analysis of the tunnel was carried out,and the excavation scheme was optimized from different aspects,and on the basis of the optimization scheme,the effect of anchor reinforcement was studied. Research shows:( 1) the bigger the excavation footage is,the greater the excavation deformation is,the bigger the displacement of surrounding rock is.( 2) The reserved core soil cycle method is more conducive to the stability of the tunnel than the full section method and three step method.( 3) Anchor reinforcement method has better effect in high stress soft rock. The results of the research can provid reference for the excavation stability and safety support of the tunnel,and for similar high stress soft rock tunnel.
出处
《地下空间与工程学报》
CSCD
北大核心
2017年第S1期245-250,共6页
Chinese Journal of Underground Space and Engineering
关键词
高应力
软弱围岩
数值模拟
开挖优化
锚杆加固
high stress
soft wall rock
numerical simulation
excavation optimization
anchor rod reinforcement
