高强度开采地表裂缝分布特征及形成机理分析

高强度开采引起的地表裂缝严重破坏矿区生态环境，对矿井的安全生产造成很大隐患。为了掌握高强度开采地表裂缝形成机理，以神东矿区地质采矿条件为基础，通过现场监测和理论分析方法，得到了地表裂缝分布规律及变形参数，分析了矿山高强度开采产生的非连续变形发育分布特征与地质采矿条件之间关系。研究表明:在高强度开采条件下，动态拉伸型地表裂缝随工作面推进而周期性地超前出现，超前距为15m，超前角为83°，裂缝密度1m左右，宽度1~3cm。台阶型裂缝总是出现在开采工作面边界的上下方、停采线上方和开切眼附近，裂缝落差20~40cm，间距8~11m，滞后距为4.2m，滞后角为86°。同时指出上覆厚风积沙松散层特性使地表裂缝具有一定的自动修复功能。

Analysis on distribution characteristic and formation mechanism of surface fissures caused by high intensity mining

The surface fissures caused by high intensity mining destroy the ecological environment of mining district seriously, and they cause hidden hazard to work safety of mine. In order to grasp the formation mechanism of surface fissures caused by high intensity mining, based on the geological mining conditions in Shendong mining district, the distribution law and deformation parameters of surface fissures were obtained by field monitoring and theoretical analysis, and the relationship between the development and distribution characteristic of discontinuous deformation caused by high intensity mining and the geological mining conditions was analyzed. The results showed that: in the condition of high intensity mining, the dynamic stretch surface fissures always appear in advance periodically with the development of working face, the advance distance is 15m, the advance angle is 83°, the density of fissures is about 1m, and the width is 1~3cm. The step fissures always appears above and below the mining face boundary, above stopping mining line and nearby the open-off cut, the drop of fissure is 20~40cm, the separation distance is 8~11cm, the lag distance is 4.2m, and the lag angle is 86°. Meanwhile, it was pointed out that the characteristic of overlying thick aeolian sand unconsolidated formation make the surface fissures with a certain automated repair function.