软弱围岩节理性质对隧道塌方范围影响研究*

为探究节理岩体在节理扩展-节理破坏-岩体失稳过程中的力学特性变化及变形破坏规律，采用块体离散元软件3DEC进行数值模拟，对节理岩体中隧道开挖后围岩的应力变形状态进行研究。结果表明:法向刚度较小时，可能造成的塌方范围大，法向刚度较大时，造成的塌方范围小；节理剪切刚度对隧道塌方范围的影响较小；节理内摩擦角变化对断层塌落体及上覆未塌落体范围的影响较小。

Study on influence of joint properties of weak surrounding rock on range of tunnel collapse

In order to explore the mechanical characteristics change and the deformation and failure laws of jointed rock mass in the process of joint propagation joint failure rock mass instability,the stress and deformation state of surrounding rock in the jointed rock mass after the excavation of tunnel was studied by numerical simulation with the block discrete element software 3DEC.The results showed that the possible collapse range was large when the normal stiffness was small,and the collapse range was small when the normal stiffness was large.The change of internal friction angle of the joint had little effect on the fault collapsed body and the overlying uncollapsed body.