Comprehensive Evaluation of the Reinforcement Effect of Grouting in Broken Surrounding Rock in Deep Roadways

With the gradual increase in mining depth, China has entered the deep mining stage. Deep mining is facing the influence of high ground stress. Additionally, due to the dual influence of working face mining, roadways are becoming seriously broken. Grouting reinforcement technology is an effective measure to ensure the stability of the surrounding rock. The evaluation of the grouting effect is of great significance to the quality assurance of grouting engineering. Taking a mine in Shanxi as an example, the effect of grouting reinforcement of broken roadways was evaluated by using the pressure and flow parameter method, permeability coefficient method, borehole TV method, mechanical parameter method and slurry filling rate method. The roadway deformation was monitored. The results show that the pressure and flow parameter method can be the technical basis for judging whether a grouting project meets the design grouting parameters. After grouting, the filling rate of the stratum grouting was 94.6%, and the stratum integrity was effectively improved; the water injection in the borehole was significantly reduced, the leakage in the borehole was reduced to 6.25% of that before grouting, and the development rate of borehole cracks was greatly reduced. Additionally, the whole crack was filled with white slurry, and the continuity of the surrounding rock was significantly improved. Moreover, the preload of the anchor bolt and anchor cable was greatly increased, to 160 kN, and the roadway deformation was reduced to less than 30 mm, meeting the requirements of normal mining of the working face.