Comparative of Subsidence Control Effect on Longwall Complete Filling and Strip Filling Mining

In order to study surface subsidence control effect of different filling methods,theory analysis and numerical simulation methods had been used to compare surface subsidence laws of longwall complete filling and strip filling,and the difference and reason of them were analyzed.The results showed that longwall strip filling mining could form strip filling body of several interval support roof under the same conditions of same filling ratio,it restricted the subsidence amount of roof and overlying strata and ensured that the key strata structure did not destroy,made the surface subsidence controllable.For longwall complete filling mining,its filling material had been evenly assigned to the whole goaf,which lead to the increase of empty top height and subsidence amount of roof and overlying strata,finally caused the broken of key strata structure and severe sink of surface,so its control effect was inferior than strip filling.With the same surface subsidence control effect,the filling ratio of longwall strip filling was obviously lower than longwall complete filling.