Abstract:Ensuring the stability of the bottom plate is the foundation for achieving safe coal mining in the fully mechanized top coal caving face. However, when there is a goaf underneath the mining area, the mining face often faces problems such as roof collapse and instability of the fully mechanized top coal caving equipment, which greatly restricts the safe coal mining and is a key problem that mines need to solve. Taking the 6303 fully mechanized mining face as the engineering background, the drilling method was used to determine the position of the overlying 9 # coal seam goaf, and the stability of the bottom plate during the mining face recovery period was analyzed through theoretical and numerical simulation technology. A reinforcement technology scheme for the goaf was proposed and applied in engineering. The research found that: ① the plastic zone of the bottom plate after the mining face recovery is connected to the overlying goaf roof, and the stability of the bottom plate is poor, After reinforcing the goaf, the stability of the working face bottom plate can be significantly improved; ② Based on the analysis of existing reinforcement materials, it was found that the filling material for the goaf can not only meet the reinforcement needs of the goaf, but also reduce the reinforcement cost and construction volume of the reinforcement project Provide a specific reinforcement drilling layout plan, filling process, and safety technical measures based on the layout of the mining roadway and detection roadway in the 6303 fully mechanized mining face. After engineering application, when the 6303 fully mechanized mining face passed through the goaf of the overlying 9 # coal seam, the working face floor and fully mechanized mining equipment remained stable, and there were no abnormalities in the mining equipment, roof and floor, and mine pressure, indicating that the reinforcement technology used had a significant effect.
