浅埋近距煤层群开采覆岩三带发育特征分析OA

The three zone rule of overburden in the mining of shallow and close-distance coal seams plays an important role in guiding the safe mining of the mine.In order to study the damage rule of overburden in the mining process of upper and lower coal seams,according to the actual situation of Hanjiawan Coal Mine,the instability mechanism of overburden struc-ture when the shallow and close-distance coal seams pass through the goaf of the upper coal seam is studied through physical similarity simulation experiments.We study the movement and deformation law of overburden and its fracture development law,mine pressure changing law,and change of the advance of the working face,as well as the movement law of surface rock strata after mining 4-2 coal seam under conditions of shallow buried and close-distance coal seam.We have found that dur-ing the mining of the lower coal seam of shallow and close-distance coal seam,the change in the subsidence of overlying rock has three stages,that is,the rising stage of subsidence,constantly unchanged stage of subsidence,and decreasing stage of subsidence.The closer the lower coal seam,the greater the overlying subsidence;the more faraway from the lower coal seam,the smaller the overlying subsidence.The study provides a basis for the prevention and control of water disasters in the mining of shallow buried and close-distance coal seams.It is of guidance and reference for the safe mining of similar repeat-ed mining faces in Yushenfu mining area.