Abstract: In order to solve the problems of the insufficient shortage of tailings pond and the land waste and hidden trouble caused by the surface subsidence pits caused by the underground mining activities by adopting caving mining method,the surface subsidence pit is processed by directly charging the tailings that is conducted grading enrichment and curing agent adding in Meishan Iron Mine.As the underground mining activities continues,the subsidence pit is the active state,the stratigraphic structure of the coverage layer of caving mining method is changed after curing and stockpiling of tailings.Some regularities of the surface subsidence pit after conducting tailing curing and backfilling are discussed based on the similar simulation test of the safety structural characteristics of coverage layer and safety stockpiling technology.The above analysis results of this paper has important significance for mining engineering.

Key words: Tailings straight ossification, Backfilling of subsidence pit, Physical simulation