Technology of roof cutting and entry retaining in fully-mechanized working face of Tashan Coal Mine

In order to solve the problem of mining and excavation alternation tension of Tashan Coal Mine, the technology of gob-side entry retaining by roof cutting and pressure releasing was carried out in the mining area. Firstly, the technical principle, technological process and key technology of gob-side entry retaining by roof cutting and pressure releasing are systematically introduced. Secondly, combined with the mine engineering geological conditions, using theoretical analysis calculation, numerical software simulation and field blasting test, it concluded that the pre-splitting kerf of the roof is 7.5 m, the angle of the kerf is 15°, the length of the constant-resistance cable is 9 m, the optimal charging structure of single hole is 4+3+3+2 and the of hole spacing is 500 mm. After the roadway is stabilized, the maximum subsidence amount of the roof is 188 mm, the maximum of the floor heave is 100 mm and the maximum shrinkage of two sides is 164 mm. The monitoring results show that the effect of gob-side entry retaining meets the production demand under the condition of roof cutting and pressure releasing.