Preliminary study of surface subsidence model based on theory of key rock stratum

The main research way of the surface subsidence due to underground mining is local observation and prediction based on the probability integral at present.These ways for studying surface subsidence is only can observe and infer the phenomenon of the subsidence;it is not study of the law for the movement process of the whole rock up the coal mining room.The rock stratum near by the surface will form a bend band when the ratio of the depth of the embedment and the thickness of the coal seam up long-wall mining coal face is very large.The bend band is one of key rock stratum near surface.Presumed this key rock stratum is controlled the rate and shape of the subsidence basin and the rate is far below the key stratum rock thick.Used the theory of key stratum to estimate the location of the rock stratum near surface and selected the suitable bending function,the surface subsidence basin model is set up by the way to survey the elasticity sheet.Discussed the applicability scope and parameter determine of this model is.This model is taken into consideration much factor of the rock stratum up the mining room,so the ideal for this model is more progress than use the probability integral function to predict the surface subsidence.