Abstract:

In order to get the deformation characteristics of protected coal seams under the condition of double pressure-relief mining, with the help of the similar material simulation experiment, the deformation rule of No.17 and 18-1 coal seams is simulated when the protective seam of No.17 and 18 are exploited in sequence in the Jinjia coal mine . The results show that deformation area of the protected coal seam is divided into four regions, which are compressive deformation region, deformation swelling region, deformation decreasing region, and deformation stability region in the strike direction. When the No.18 coal seams is exploiting, by the process of re-compressed, deformation increasing, decreasing, and stabilizing, the four regions of the protected coal seams are redistributed. The deformation regions in the dip direction showed M-shaped form. The dominant factor of deformation of No.17 and 18 coal seams are No.17 and 18-1 coal seams respectively.

Key words: closed distance seam group, pressure-relief mining, similar simulation, deformation