Energy dissipation and crack propagation in gas-containing coal under impact loading: An experimental study

Abstract

Gas-containing coal seams are highly susceptible to coal and gas outburst and composite dynamic disaster due to dynamic loads generated by roof breaks and blasting. This is an energy-driven state destabilization phenomenon, and is intricately correlated to the development of the cracks (i.e. damage evolution) within the coal. To accurately understand the energy evolution and damage principle of gas-containing coal under impact loading condition, we conducted impact compression experiments on the coal body under varying gas pressures. We analyzed the compression energy dissipation characteristics of the coal body under different gas pressures. Additionally, we utilized the CT scanning system to obtain the fracture evolution laws of gas-containing coal under the impact loading condition, and we explored the damage law of the gas to the coal body. In addition, the energy required for crack energy dissipation density (CEDD) is introduced to quantitatively characterize the relationship between energy dissipation and crack propagation.