Research on reasonable mining scheme for coal recovery in thick coal seam under buildings and other structures.

Due to overe xploitation in the last years, coal under buildings and other structures has become a significant resource to maintain the sustainability of coal mines in China. However, buildings and other structures above mining area are easily damaged caused by surface subsidence after mining. In order to recover coal under surface structures and ensure the stability of surface structures, the short-strip coal recovery with backfill method is proposed. By using a numerical simulation, this paper simulates the subsidence of overlying strata to select the mining sequence and the strip width. A reasonable mining sequence is determined and the strip width is primarily selected as 5m or 6m. Afterward a physical simulation is conducted to validate the numerical simulation. And the subsidence law of overlying strata during mining and filling is analyzed for the 5m-width and 6m-width strip respectively. Finally, the reasonable strip width is determined as 6m according to the surface subsidence and production efficiency. By employing the above mining scheme, the surface subsidence and deformation of two surface structures above the mining area of Sima coal mine is predicted, which shows the mining scheme can ensure the stability of two surface structures above mining area. The research results provide a reasonable and reliable reference for coal recovery in thick coal seam under buildings and other structures. [ABSTRACT FROM AUTHOR]