基于声发射活动参数的岩石破裂过程应力阈值确定

Defining Stress Thresholds of Rock Failure Process Based on Acoustic Emission Activity Parameters

在实验室应用声发射监测系统,对25块花岗岩样进行单轴压缩实验.通过连续实时监测花岗岩样破裂全过程中事件率、累计能量、能率、持续时间和振幅等声发射源特征参数的变化规律,获得岩样破裂过程各加载阶段的应力阈值.将岩石试件破裂全过程中各个阶段的应力阈值与峰值强度进行比较,并与以往实验结果对比,发现岩石变形特性和裂纹演化规律具有统一性.

The uniaxial compression experiments were carried out on 25 granite samples by application of acoustic emission testing system in the laboratory. Through continuous real-time monitoring these characteristics of the acoustic emission sources such as event rate, cumulative energy, energy rate, time duration and amplitude in the failure process of granite rock samples, the stress thresholds at each loading stage were obtained in the whole failure process. Furthermore, by comparing the stress threshold at each stage with peak strength during the process of rock fracturing and with previous experimental results, we find that rock deformation characteristics are consistent with the evolution of the crack in rock.