断层泥倾角对隧道稳定性影响的数值分析

以某铁路隧道为例，运用FLAC3D数值软件模拟不同断层泥倾角对隧道稳定性的影响。结果表明:掌子面轴向位移、初支弯矩沿开挖方向可以分为3个阶段，即完整围岩稳定阶段、交界面临近位置变化阶段及断层破碎带段稳定阶段。在距离交界面较远的位置，位移、内力沿隧道纵向变化较小，与在单一土层或岩层中开挖相似。在土岩交界面临近位置，随着断层泥倾角的增大，土岩交界面影响的范围减小。围岩及初支的位移、内力曲线对开挖进深的敏感性不同，随着断层泥倾角的增大，围岩及初支的位移、内力曲线斜率更大。

Numerical Analysis of the Effect of Fault Gouge Dip Angle on Tunnel Stability

The influence of different fault gouge dip angles on the stability of tunnels was simulated by FLAC3D numerical software based on a railway tunnel. The results show that the axial displacement of the face and the initial bending moment can be divided into three stages along the excavation direction, namely, the stability stage of the complete surrounding rock, the interface near-position change stage and the stable stage of the fault fracture zone. At a distance from the interface, displacement and internal force with the longitudinal variation along the tunnel is small, similar to excavation in a single soil or rock formation. At the confining position of the soil and rock, with the increase of the fault gouge dip angle, the influence of the interface of the soil and rock is reduced. The displacement and internal force curves of the surrounding rock and the initial support are different on the sensitivity of the depth of the excavation. With the increase of the fault gouge dip angle, the displacement and the internal force slope of curve of the surrounding rock and the initial support is larger.