厚黄土下综放高强度开采地表沉陷与覆岩破坏实测

Field Measurement on Ground Subsidence and Overburden Failure by High Intensity Fully Mechanized Top-coal Caving Under Thick Loess

为研究厚黄土下厚煤层综放开采地表沉陷和覆岩破坏规律,通过在工作面地表建立岩移观测站和地面钻孔水文勘探,进行了地表沉陷变形实测和覆岩破坏高度钻探测定。总结研究地表岩移观测站实测资料和覆岩破坏探测钻孔水文观测资料,得出厚黄土综放高强度条件下地表沉陷剧烈,曲线较陡,在下沉盆地边缘沉陷变形曲线收敛较慢,最大下沉速度偏大,采动影响范围偏远;覆岩破坏探测结果显示综放覆岩破坏异常发育,导水裂缝带高度与综放采厚近似成正比,裂高采厚比例系数平均为19.75。研究成果为黄土区综放地表开采损害防治和水体下采煤及顶板水害防治提供技术支撑。

In order to study the law of ground subsidence and overburden failure induced by fully mechanized top coal caving under thick loess,the measurement of surface subsidence and deformation and the height of overburden failure are detected through the establishment of ground observation stations and hydro-geological drilling exploration in surface. A great number of field data from ground observation stations and hydro-geological drilling exploration are collected. It is shown that ground subsidence under fully-mechanized caving of thick loess moved intensively with steep subsidence curve. The converge of subsidence and deformation curve at the edge of basis grows slowly. Maximum subsidence velocity is higher,and mining influence scope is much too far away. The detection of overlying rocks damage indicates that the overburden failure is developed abnormally in mining with fully-mechanized top-coal caving system,and the height of the water conducted zone is directly proportional to the total mining thickness. The ratio of the fracture height and the mining thickness is obtained to be 19. 75 at average. The research can provide technical support for controlling surface mining damage and roof water inrush in coal mining under water in loess region.