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 surfac...