The coal seam floor layout bottom drainage roadway is one of the effective means of gas outburst elimination in the working face. However, the roof surrounding rock of the bottom drainage roadway will undergo multiple disturbances such as bottom drainage roadway excavation, drilling excavation, roadway excavation and working face mining, which will easily lead to large deformation of the surrounding rock of the bottom drainage roadway, which will greatly affect the safety and stability of the bottom drainage roadway and the safety of the mine. In this process, the fracture of the borehole wall of the extraction borehole expands, and it is subjected to severe dynamic pressure during roadway excavation and working face mining. At the same time, the redistribution of surrounding rock stress brings secondary damage, which will lead to the increase of roof deformation. Based on the maintenance of the roof surrounding rock of the bottom suction roadway in the 14020 working face of Zhaogu No.2 Coal Mine, aiming at the problems of local large deformation of the roof surrounding rock of the bottom suction roadway and the difficulty in maintaining the roadway caused by the mine pressure appearance, in order to reduce the roof disturbance of the bottom suction roadway and strengthen the roof support, the indoor test, numerical simulation, theoretical analysis and industrial test are used to carry out the research on the deformation law of the roof surrounding rock of the bottom suction roadway and the bolt grouting reinforcement technology. A numerical calculation model of multiple disturbances in the bottom drainage roadway considering the construction of drainage boreholes was established. The causes of deformation and failure of the roof of the bottom drainage roadway were analyzed, and the supporting parameters and techniques were improved. The timing and support scheme of the test roadway support ( reinforcement technology ) were determined. Under the condition of high strength support, the influence law of bottom pumping roadway excavation, drilling excavation, roadway excavation and working face mining on the deformation degree of roof surrounding rock is revealed. The active reinforcement technology of bolt-grouting for surrounding rock of test roadway is put forward and applied in the field. According to the feedback of the on-site mine pressure monitoring results, the roof deformation degree of the test roadway after excavation and mining is small, and the roadway section meets the production demand, which verifies the feasibility of the bolt-grouting reinforcement technology.
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