Stability Analysis of Backfill and Underground Pressure Control in the Large-Scale Deep Mining

摘要

For the reason that Anhui Shapinggou Molybdenum mine with large-scale deep mining appears obvious underground pressure, the arch facade sequence mining and subsequent backfilling are designed for controlling the frequent underground movement. The numerical analyses of arch facade mining sequence and conventional upward horizontal slice mining sequence are carried out respectively, and static calculation and dynamic calculation are carried out for the stability of backfill. The analytical results show that the maximum principal stress distribution is uniform in the arch facade mining, and the arch facade mining has smaller degree of stress concentration and less plastic area than those of conventional sequence mining. Because of a better supporting role arising from the vaulting, the surface subsidence displacement caused by arch facade mining is smaller than that caused by conventional sequence mining. The operating range of blasting vibration influences the variation of plastic zone and displacement for backfill. When the blasting dynamic loading is applied near the backfill, the distribution area of backfill plastic zone is expanded obviously. If the curing time of backfill is insufficient, the backfill is prone to collapse.