Surface subsidence law of filling with super-high-water material and skip mining

In order to research the surface deformation law and the subsidence controlling effect of filling with superhigh-water material and skip mining,based on the observation data of a coal mine,the surface deformation law of every filling and skip mining step was studied. Used the key strata theory and numerical simulation with FLAC3Dsoftware,the relationship between key strata breaking and surface sinking in time and space was studied,the main factors of surface subsidence were analyzed,and the effect of surface subsidence controlling was evaluated. The results show that in the mining condition of 340 m depth and 4 m thickness,the maximum subsidence is 1 174 mm,the subsidence coefficient is 0. 29,the subsidence reducing ratio is 62. 8%,the extraction ratio is 89. 2%,and the scope of subsidence basin is reduced obviously. The analysis results show that surface subsidence could be reduced by filling,and the shape of subsidence basin could be controlled by skip mining,in order to protect important buildings on the earth.