Study on the Migration Law of Overlying Rock in the Upward Layered Continuous Mining Face of Thick Coal Seam with Paste Backfill Mining

With the massive mining of coal resources, coal mining under special conditions such as “Coal mining under buildings and railways and water-bodies†thick coal seams has became a key concern for relevant scholars. As a mining method to effectively replace “Coal mining under buildings and railroads and water-bodies†thick coal seams, paste backfilling is an important part of the coal green mining system. In this paper, by combining theoretical analysis, numerical simulation, and other means, the migration law of overlying rock in paste backfill mining of continuous mining face in thick coal seam upwards under the village was studied. FLAC3D numerical simulation software is used to analyze the upward separation of thick coal seams. Surface subsidence was simulated at each stage of paste backfill mining in the continuous mining face, and the influence of the backfill elastic modulus on the overburden subsidence, the backfill and coal stress, the range of the overlying plastic zone, and the surface deformation was simulated and analyzed. The elastic modulus of the filling body was finally determined.