Numerical Simulation of Coupling Charge Coefficient on Permeability Increasing Effect of Deep Hole Pre-splitting Blasting Based on ANSYS

In order to study the effect of deep hole pre-splitting blasting on coal seam under different coupling charge coefficients, four sets of blasting models with different coupling charge coefficients were established and simulated by ANSYS / LS-DYNA. The stress nephogram and stress time history in x direction are obtained; the results of the analysis are as follows: when K=1.5, the crack propagation length is longer than that K=1.0; the uncoupled charge structure makes the effective stress distribution more uniform; with the increase of the coupling charge coefficient, the effective stress range decreases, which is less than that in the case of complete coupling; appropriately increasing in coupling charge coefficients can improve the energy efficiency and achieve the better permeability increasing effect; continuously increasing the coupling charge factor, the cracks do not extend to the control hole.