Study on the Stress Field and Crack Propagation of Coal Mass Induced by High-Pressure Air Blasting

High-pressure air blasting (HPAB) is one type of physical technique that enhances the extraction rate coalbed methane by impacting coal mass with high-pressure gas to create cracks within it. First, based on and mechanical parameters simulated rock mass, RHT constitutive model was established, its were determined. Then, laws crack propagation stress wave decay in induced revealed comparing effect equivalent explosive blasting. Next, HPAB experiment explore law under in-situ conditions. Finally, carried out results this compared numerical simulation results. The indicate considered as two major stages, i.e., initiation stage stable duration gas. In case equal energy, peak smaller, decays more slowly has a longer action time, Therefore, number initial random less, range larger. When λ = 0 (λ ratio horizontal vertical stress), seam can promote but inhibit cracks. 0.5 1, inhibits both