Research on the technology of pressure relief by intensive drilling and segmented control in facing excavation roadway

In view of the problems of serious deformation and damage as well as difficult maintenance to hard roof of the facing excavation roadway due in Tanyaoping Coal Mine, the dynamic evolution law of the vertical stress of the surrounding rock of this type of roadway was analyzed by combination of theoretical analysis and numerical simulation, the deformation and failure mechanism of the surrounding rock of the roadway under the superimposed disturbance effect of dynamic and static was revealed, and the technology of "roof cutting and pressure relief by intensive drilling and segmented control" was proposed. The results show that the vertical stress distribution of the facing excavation roadway presents three stages along strike: the initial stage (beyond 50 m ahead of the working face), the rapid rise stage (from 50 m ahead of the working face to 150 m behind the working face) and the stable stage (beyond 150 m behind the working face). The reason for the deformation and damage of the facing excavation roadway is: superposing the lateral support pressure generated by the large-area suspended roof in the goaf and the dynamic load generated by the mining of the adjacent working face. Specifically, the technology of "roof cutting and pressure relief by intensive drilling and segmented control" is to arrange intensive drilling with a diameter of 65 mm, a depth of 18 m, and a hole spacing of 400 mm on the coal pillar side roof of the working face. Under the influence of mining in the working face, the plastic zone between the drillings is connected, and the fracture position of the main roof is actively controlled. The practice shows that the technology of "roof cutting and pressure relief by intensive drilling and segmented control" has guiding significance for the stability control of surrounding rock in similar roadways.