Grouting Reinforcement Technology of Coal Mining Face with Thin Base Rock Broken Roof and Brittle Fracture Coal Mass

In order to solve the spalling and the roof falling problems of the deep thin base rock broken roof and the brittle fracture coal wall,taking No. 11131 coal mining face of Zhaogu No.1 Mine as a study object,a site observation method was applied to have the features of the coal mass cracking development and the roof falli ng. Bingham fluid diffusion movement equation was applied to calculate the max diffusion radius of the grout in the coal wall of the coal mining face. The paper provide d the method to calculate the elevation angle of the grouting borehole,the layout pattern of the grouting boreholes was optimized and a grouting reinforcement was cond ucted in the coal spalling area of the coal mining face and broken area of the coal wall. The results showed that after the grouting reinforcement of the coal mining face conducted,the coal wall spalling and roof falling accidents were highly reduced,the forward advancing rate of the coal mining face was improved from3. 2 m/dto6.7 m/d.