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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.

In order to liberate the shallow quaternary loose aquifer coal pillar resources, taking the 1010-1 working face of the first mining area of Wugou Coal Mine as the test object, the grouting reinforcement test of quaternary loose aquifer and the weathering zone of the bedrock at the bottom was carried out by using the splitting grouting method and the grouting technology combining continuous and intermittent grouting. The results show that: the quaternary loose aquifer control area has complex lithology and weak water content, and mainly receives runoff recharge from the lateral area. The grouting reconstruction project adopts the water displacement and sand fixation scheme of the ground straight hole combined with the directional oblique hole row by row; the strength of the mixed slurry is subject to the ratio of fly ash, and the strength and stone rate of the mixed slurry are higher than those of the cement net slurry. When the fly ash content is 20%, the stone rate is the highest; the diffusion of grout in the quaternary loose aquifer is very uneven, the grouting process needs to control the grout diffusion range by controlling the grouting amount, the influence of grouting on the surface is reflected in the grout diffusion and pressure conduction, and the pressure conduction is the main one; after injection, the true density and water content of the core hole samples slightly increased, while the compressive strength, tensile strength and shear strength slightly increased; with the increase of sampling depth, the compressive strength of the rock layer in the wind-oxidized zone of bedrock increased first, then decreased and then increased, and the compressive strength increased about 2-5 times.