Roof control technology for longwall filling mining of superhigh-water material

To analyze the impact of filling face length on strata controlling,direct the practice of longwall filling mining,and provide basis for deformation control of surrounding rocks,based on the basic properties of the material,the authors built the mechanical model of overburden strata movement in the filling minning of superhigh-water material to obtain the predicting bending deformation of key strata and analyze influence of filling mining face length on the deformation and fracture of key strata,and proposed roof control philosophy of longwall filling minning by thin plate theory of difference method. The studies show that the roof subsidence of mining goaf increases with increasing length of mining face distance,and the key strate may keep stable structure without breaking at a certain range of the length of mining face and roof distance. Through comparing the mining geological condition of No. 1-5 and No. 6 filling coalface in Taoyi Coal Mine of Jizhong Energy Group,four longwall roof control techniques of surface filling system construction,filling level elevation,isolation strip setting and bolt-mesh-anchor support of mining face were proposed and applied,which can not only effectively inhibit roof deformation,but also guarantee the good filling effect.