Optimization and application of bolting and grouting support parameters in roadway with fractured surrounding rock

In view of the loose, broken and serious deformation of the surrounding rock of the connection roadway in the south of 730 mining area of Xinhe Mining Company, the influence of different grouting parameters on the slurry diffusion was discussed by using Comsol Multiphysics finite element analysis software; on this basis, the influence of different grouting anchor cable arrangement on grouting effect is studied. The results show that the slurry diffusion radius will gradually increase with the increase of grouting pressure and grouting time. The average growth rate of slurry diffusion radius is 30.95% for each increase of 1 MPa grouting pressure and 25.67% for each increase of 1 min grouting time; the layout of the grouting anchor cable determines the scope of the grouting reinforcement circle. When the “hexagon” layout is adopted, the scope of the grouting reinforcement circle is relatively large, and there will be no slurry leakage on both sides of the roof. Based on the numerical simulation results, it is determined that the grouting pressure of the bolt-grouting support of the connection roadway in the south of Xinhe Mining Company is 4 MPa, the grouting time is 8 min, and the grouting anchor cable arrangement scheme is “hexagon” type. The engineering application shows that the optimized grouting parameters effectively control the deformation and damage of the surrounding rock of the roadway, and obtain good engineering results, and also provide an effective basis for the grouting reinforcement of such roadway.