Experimental investigation of mechanical properties, impact tendency, and brittleness characteristics of coal mass under different gas adsorption pressures

Understanding the mechanical properties of coal after gas and interaction can better guide mining technology gas-bearing seams drainage coalbed methane. In this study, triaxial compression tests mass under different adsorption pressures are carried out to evaluate properties, impact tendency, brittleness with pressures. Results show that due gas, parameters, such as elastic modulus strength significantly decreased. addition effect fluid pressure, decrease energy absorbed by coal, increase ductile deformation change molecular structure particles caused also affect coal. The influence pressure on input becomes gradually evident when enters stage plastic yield failure. Then stress bearing capacity affected, accumulation dissipation process further affected. generally develops absorption density three characteristic points (initial damage point, volume expansion point peak point), but reduces these points. Gas storage strengthens dissipation, failure characteristics It is not prone appear sudden brittle in mass. Although high risk rock burst, it increases outburst. chemical effects pore/fracture combined action adsorbed free lead decline brittleness, thus changing mode