隐伏断层诱发巷道底板突水研究

Study on Water Inrush from Roadway Floor Induced by Buried Fault

隐伏断层在掘进扰动和承压水共同作用下可能形成突水通道诱发底板突水。以山西省刘家梁煤矿巷道突水问题为工程背景,以底板含隐伏断层的巷道为研究对象,通过理论分析、岩石力学试验、数值模拟的方法,研究了巷道在掘进过程中,围岩应力场、位移场、塑性区的演化情况。结果表明:随着巷道掘进,隐伏断层顶界面处围岩受应力场影响,由压缩态变为膨胀态;在倾角大于50°的正断层中,小倾角隐伏断层顶界面处围岩受到的剪应力峰值更大,当剪应力达到某一临界值时,断层不断向上活化扩展,最终演化形成沟通底板破坏带的突水通道,且突水通道更易在卸压区底板贯通。

Under the combined action of excavation disturbance and confined water, buried faults may form water inrush channels which can induce floor water inrush. Taking the water inrush problem of Liujialiang coal mine roadway in Shanxi as the engineering background and the tunnels with buried faults in the floor as the research object, through the theoretical analysis, rock mechanics test and numerical simulation, we studied the evolution of country-rock stress field, displacement field and plastic zone during the excavation of tunnels. The results show that the country-rock at the top interface of buried fault changes from compression state to expansion state under the influence of stress field with the excavation of tunnels. For a normal fault, if its dip angle is larger than 50°, the shear stress peak value of the country-rock at the top interface of the buried fault with a small dip angle is larger. When the shear stress reaches a certain critical value, the fault continues to activate and expand upward, and finally evolves into a water inrush channel connecting the floor failure zone, it should be noticed that the water inrush channel is easier to penetrate the floor of the pressure relief area.