深部逆断层圆弧形断面诱发煤岩动力灾害的力学分析

Mechanical analysis of underground dynamic disasters induced by thrust faults of an arc fault plane

为了探索逆断层附近易于发生煤岩动力灾害的力学机制,构建了由构造应力为主导的圆弧形断层面简化力学模型,得到了构造应力以及由其引起附加垂直应力的分布规律,进而建立了断层上盘逆冲滑动临界角度的数学模型。研究表明:水平构造应力与附加垂直应力随着断层倾角的增大而增大,当断层倾角接近90°时,附加垂直应力突然增大且其值数倍高于水平构造应力;基于逆断层滑动的力学分析,理论计算了煤层沿断层逆冲滑动的临界角度,这将对煤岩动力灾害的危险性预测有一定的参考意义。

To discover the mechanism of underground dynamic disasters close to thrust faults of an arc fault plane,a simplified mechanical model of arc fault planes under the influence of horizontal tectonic stress is constructed.The distribution laws of both horizontal tectonic stress and additional vertical stress induced by the tectonic stress are acquired,and then a mathematical model of the critical angle of thrust-shear slide of hanging wall is set up.The study results show that both horizontal tectonic stress and additional vertical stress increase with the increase of a fault dip.When the dip angle is close to 90°,the additional vertical stress increases rapidly,and its maximum is several times higher than the tectonic stress.The critical angle of the fault thrust sliding is calculated based on mechanical analysis,and this is hoped to provide some reference for the early warning dynamic disasters about coal and rock.