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对劈裂和单轴压缩条件下原煤损伤破坏全过程的声发射特征规律进行了对比研究。研究表明,单轴压缩破坏时,加载初期声发射信号较少;在弹性变形阶段后期和塑性变形阶段,声发射信号呈剧烈增加趋势;声发射能量和声发射脉冲数在破坏阶段达到最大值。劈裂试验时,在裂纹的加速非线性弹性变形阶段开始产生声发射信号;声发射能量和脉冲数在破坏阶段达到最大值;但是与单轴压缩相比,劈裂试验下声发射信号出现较晚,声发射能量较低,脉冲数较大;未观察到与单轴压缩实验类似的“裂隙压密”阶段声发射脉冲数较高的现象。
The acoustic emission characteristics of the entire process of damage and destruction of raw coal under the condition of splitting and uniaxial compression were studied comparatively. The results show that there is less acoustic emission signal at the initial stage of loading under uniaxial compression failure. At the late stage of elastic deformation and plastic deformation stage, the acoustic emission signal shows an increasing trend. The acoustic emission energy and acoustic emission pulse number reach the maximum during the failure phase. In the splitting test, the acoustic emission signals begin to be generated during the accelerated nonlinear elastic deformation of the crack. The acoustic emission energy and the number of pulses reach the maximum value in the failure phase. However, compared with the uniaxial compression, Later, the acoustic emission energy was lower and the number of pulses was larger. The phenomenon of higher number of acoustic emission pulses in the “crack compact” stage similar to the uniaxial compression test was not observed.