Diffusion mechanism and sensitivity analysis of slurry while grouting in fractured aquifer with horizontal injection hole

Investigating the diffusion law of slurry while grouting in fractured aquifer is of great significance to the safety in coal mining. In this paper, we comprehensively studied the slurry diffusion in the fractured aquifer, which was grouted through horizontal injection holes. A theoretical model of slurry diffusion in the inclined tubular fractures, as well as the relationship between the distance of slurry diffusion and the grouting time, was established. Then the influence of different factors on the distance of slurry diffusion was analyzed, including rheological coefficient, the fracture width, grouting pressure, the fracture dip angle, and the velocity of flowing water. Finally, sensitivity analysis on the distance of slurry diffusion for pseudoplastic fluid and expansive fluid along the flowing water direction was made and the results show that the sensitivity of each factor to the diffusion distance of the two fluids along the flowing water is different, rheological index is the very significant factor to the diffusion distance of pseudoplastic fluid. However, for the expansive slurry, the fracture width is the very significant factor to the diffusion distance of it.