School of Emergency Management and Safety Engineering China University of Mining and Technology Beijing Beijing 100083 China;
Safety Engineering College Beijing Institute of Petrochemical Technology Beijing 102617 China;
School of Emergency Management and Safety Engineering China University of Mining and Technology Beijing Beijing 100083 China;
School of Emergency Management and Safety Engineering China University of Mining and Technology Beijing Beijing 100083 China;
Cumulative blasting; Fracturing mechanism; Coalbed permeability improvement; Permeability improvement technology; Gas extraction;