Control and stability analysis of subsided mined-out area

Underground mined-out area collapse caused by mining activities in Maoping lead-zinc mine leads to surface subsidence and cracks,endangers the safety of surface and affects the mining of orebody.A series of treatment measures which include filling and closing collapsed mined-out area,reinforcing filling body by using high and low pressure grouting from surface and cleaning up the dangerous rock on the surface have been adopted to control mined-out area.Stability analysis and evaluation are carried out for the situations before and after the treatment of mined-out area by using numerical simulation.The analysis results considers that the treatment measures adopted by Maoping lead-zinc mine could guarantee the stability of surface and safety mining of deep orebody.