A new theoretical model for guiding the gas extraction in coal mines

Based on the fractal-percolation properties, the equivalent permeability analysis of 3-D discrete fracture network models are investigated and analyzed for the first time. The 3-D fractal dimension was calculated with the 3-D fracture density, the mean major axis of fracture and the aspect ratio of major to minor axis. The reconstructed mining-induced fracture network model was used to validate that the correlation between the predicted and actual results is very strong in a sense. The equivalent permeability results can be adopted to guide the gas extraction in coal mines.