Study on stability of goaf overlying strata with “110 construction method” in Shennan mining area

Based on the engineering background of Shennan mining area,the structural characteristics of the rock structure of the main rock layers in the mining area were analyzed by rock microscopical laboratory experiment,field monitoring,physical simulation experiment ( DIC monitoring and strain monitoring) and FLAC3D numerical simulation. The evolution law of the displacement and stress fields of overlying in goaf rock ingoaf under the mining technology of “110 construction method” (a new mining technology without coal pillar) was obtained. The research results show that the rock mass in Shennan mining area has a high degree of joint fracture development and the quality grade of rock mass is poor. The 110 construction method still has good effect of gob-side entry retaining in the mining of coal seam with kilometer level burial depth by using the fragmentation and expansion effect of rock mass and high constant resistance energy absorbing anchor cable compensating mechanical support characteristics. The displacement settlement law of the mining area under the 110 construction method is central area > tangent side area > non-tangent side area. The combined mining technology of 110 construction method of roof cutting and pressure relief and high constant resistance energy absorbing anchor cable can provide scientific basis for the stability study of large deformation and weak surrounding rocks in other underground spaces.