Study on Strata Bearing Structure and Surface Deformation of Strip-filling Mining

We used the method of FLAC^3D and field measurement to study the strata bearing structure and surface deformation of strip-filling. The test results show that a single strip filling body can not form bearing structure; plastic body bearing structure of the overburden rock is formed by the interaction of the adjacent strip-filling body; spacing interval variation characteristics of bearing structure is related to the key stratum in the overburden strata; under the influence of completely mining, the surface displacement of strip-filling mining is reduced by 65% compared with filling mining; the maximal displacement of strata is reduced by 35%, and maximum surface subsidence of strip-filling mining is only 26.8% compared with no filling mining; the results of field measured and numerical simulation are almost the same; strip-filling mining can effectively control the surface deformation; the ground deformation is levelⅠgrade.