Abstract：In order to improve the effect of coal gas extraction, taking the blasting and permeability improvement of No.18204 Face in Shaping Coal Mine as the research object, the discrete element method is used to study the velocity field, stress field and fracture field under the conditions of no control hole and control hole radius of 60 mm, 80 mm and 100 mm respectively. The results show that the larger the diameter of the control hole, the greater the reflection degree of the stress wave, the greater the range of the stress concentration zone, the greater the frequency of fracture development around the control hole, the greater the degree of connectivity, and the more conducive to the fracture along the ' blast hole-control hole-blast hole '. On this basis, the field test of deep hole blasting antireflection in No.18204 Face was carried out. The results show that the average gas concentration of large diameter control hole and control hole with radius of 100 mm increases by 96.7% ~ 99.3%, and good blasting antireflection effect is obtained. The research results can provide reference for blasting parameter design and scientific research of blasting antireflection operation.
