ABSTRACT
Based on the key stratum theory in ground control, an idea of partial backfilling for controlling coal mining subsidence is put forward: only a part of the goaf instead of the whole is to be filled on condition that the width of the unfilled goaf is less than the initial break span of the primary key stratum and the backfilling strips can maintain stability, then the surface subsidence can be controlled effectively. By doing so, the filling volume reduced, resulting in a decrease of cost. According to the mining conditions of Xuchang coal mine, the feasibility, applicability and applying schemes of partial backfilling for controlling mining subsidence have been researched through numerical simulation.
