在MTS815.02岩石力学试验系统上进行了煤的单轴压缩、三轴压缩及孔隙水作用下全应力应变试验及声发射检测.结果表明:煤的三轴强度、残余强度随围压增高而增大,随孔隙水压增高而降低;在低围压试验范围内,煤的弹性模量不随围压变化.煤在不同试验条件下呈现的声发射特征有显著差异性:单轴试验时各个阶段均有声发射事件产生,三轴及孔隙水试验条件下煤样屈服之前声发射事件较少,而屈服之后声发射趋于活跃;单轴试验时煤的声发射能量最大,随孔隙水压增大,煤样变形过程释放的声发射能量逐渐减小.
Full stress-strain tests and acoustic emission measurements under uniaxial compression,triaxial compression and pore water pressure were carried out on coal samples with an MTS815.02 rock mechanics test system.It is shown that the triaxial strength and residual strength increase with the increase of confining pressure but reduce with the increase of pore water pressure.In the testing range of low confining pressure,the elastic modulus has great change with confining pressure.Under different testing conditions,the acoustic emission behaviors of coal samples have great differences.Under uniaxial compression test,there are all acoustic emission events at each stage,but under triaxial compression and pore water pressure,the acoustic emission events are smaller before yielding and tend to be active after yielding.The acoustic emission energy of coal samples under uniaxial compression is the largest.With the increase of pore water pressure,the released acoustic emission energy decreases step by step in the process of deformation.