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It is very important and effective to characterize the failure mechanism of coal and rock materials from the perspective of energy. Energy dissipation and release are important causes of rock mass failure. To qualitatively and quantitatively characterize the energy evolution process of gas-bearing coal and the energy evolution mechanisms of coal and gas outburst, experimental studies were conducted on gas-bearing coal under different stress paths. The research results demonstrate that the energy evolution of gas-bearing coal has nonlinear characteristics and that the energy density is a quadratic function of stress. The total energy density is mainly stored as elastic energy density and is unrelated to loading paths. According to the distribution characteristics of abutment pressures in a stope, the energy distribution can be divided into an energy dissipation and release zone, an increasing-energy zone, and a stable energy storage zone. During coal mining, abutment pressure in front of the coal wall is an important factor causing energy accumulation, and the stress concentration area is a key area to prevent and control dynamic disasters of coal and rock masses. Furthermore, based on the principle of energy conservation, this study established an energy balance model for coal and gas outburst and derived energy criteria for coal and gas outburst. When $$\Upsilon > 1$$ , there is a risk of coal seams have outburst. If $$\Upsilon = 1$$ , the system is in a state of limit equilibrium, and mining disturbances could trigger outburst.

In deep mine, coal is usually subjected to coupled high gas pressure and static compressive stress. The coal may be also subjected to dynamic loading due to the sudden fracture of hard roof during mining. In our previous study, the behaviour of gas-containing coals with initial gas pressure was investigated subjected to uniaxial static compression. In this study, the dynamic compressive behaviour of gas-containing coals with gas pressure and static axial preloading is investigated using a modified Split Hopkinson Pressure Bar (SHPB) system. The dynamic behaviours of gas-containing coals under SHPB tests are studied by varying initial gas pressure and axial static preloading. The testing results include strain measurements and energy dissipation. In addition, the wave impedance method is used to quantify damage of gas-containing coals under coupled gas-static-dynamic load. It is found that the dynamic compressive strength of gas-containing coal under coupled load decreases with the increasing initial gas pressure. The gas-containing coal with higher gas pressure and axial static preloading is more vulnerable to dynamic loading. The findings can be applied to mining design or support design in deep mining of high-gas-containing coal seam.