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依据声发射测试原理,建立了微裂纹成核时声发射率与应力,晶粒直径、位错数目的定量表达式,表明晶粒大小对声发射有较强的控制作用。晶粒断裂时,声发射参数与单轴应力、断裂指数有关,即声发射与材料的性质及应力状态有关。对于有预制裂纹的试样,低脆性岩石声发射与裂纹尖端塑性区大小有关,指数b取决于材料的强度特性;高脆性岩石声发射主要受裂纹扩展速率控制。
According to the principle of acoustic emission test, the quantitative expressions of acoustic emissivity and stress, crystal grain diameter and dislocation number were established when microcrack nucleation, indicating that the grain size has a strong control effect on acoustic emission. Acoustic emission parameters are related to the uniaxial stress and fracture index at grain breakage, ie the acoustic emission is related to the material properties and the stress state. For pre-cracked samples, the acoustic emission of low-brittle rock is related to the size of the plastic zone at the tip of the crack. The index b depends on the strength characteristics of the material. The acoustic emission of highly brittle rock is mainly controlled by the crack propagation rate.