Research on Pre-grouting Reinforcement and Support Technology for Weak Interlayer Roof Stoping Roadway

In order to reduce the deformation of roadway surrounding rock under complex geological conditions and improve the efficiency and safety of roadway excavation, taking the F6101 comprehensive excavation working face of Buliangou Coal Mine as the research object. Pre-grouting surrounding rock reinforcement technology is adopted to conduct reinforcement on the roadway surrounding rock before excavation. The deformation situation of the roadway surrounding rock before and after grouting reinforcement is concluded by FLAC^3D numerical simulation, the roof subsidence amount is reduced by 33.6% and the two sides deformation amount is reduced by 37.4%. Through downhole actual grouting experiments, the diffusion characteristics of the grouting fluid in the downhole surrounding rock are determined, and the optimal support scheme for the roadway is determined combined with the geological conditions of the construction area. The monitoring shows that under the situation with same support scheme, the roof subsidence amount in the area adopted with grouting reinforcement is 62.4% lower than that in the area without grouting reinforcement, and the movement amount of the roadway two sides is reduced by 73.2%, grouting reinforcement can improve the stability and bearing characteristics of the surrounding rock.