不同交角断层对隧道围岩稳定性的影响

Influence of Different Strata Angle Fault on Tunnel Surrounding Rock Stability

为分析隧道与断层走向的不同交角对隧道围岩稳定性的影响,借助有限差分软件FLAC3D对四种不同的隧道和断层带交角情况进行数值模拟,对比分析断层带围岩位移和初支应力分布规律,以及断层带对隧道扰动范围。模拟结果表明,隧道轴向与断层带走向的交角大小是影响隧道稳定性的重要影响因素。隧道和断层带垂直相交时,断层带对隧道扰动范围小,但围岩位移和初支应力变大。因此,应综合考虑三方面因素的影响,确定隧道穿越断层的最优交角。

In order to analyze the law of stability of tunnel surrounding rock passing through the different strike angle fault fracture zone, this paper gives numerical simulation of four different angular of the tunnel and fault zone with the help of finite difference software FLAC3D.And also gives the contrast analysis of displacements of the surrounding rock in the fault zone and distribution law of initial stress, as well as tunnel disturbance range by the fault zone. The simulation results show that angular of the size between the tunnel axis and fault strike is an important influence factor which influences the stability of the tunnel. When the angular between the tunnel and fault zone is 90°, tunnel disturbance range by the fault zone issmall, but displacements of the surrounding rock and initial stress is bigger. Therefore, it should be considered the effect by three factors above mentioned to determine the optimal angle of tunnel crossing fault.