随机性对低均质度岩石声发射时序特征的影响

Influence of Randomness on the Acoustic Emission Sequential Characteristics of Rock with Low Homogeneity

为了研究随机性对低均质度岩石声发射时序特征的影响,采用数值模拟软件RFPA2D进行岩石单轴压缩破坏过程模拟。通过设计正交试验方案,以试验结果的离散系数为评价指标,衡量随机性对声发射时序特征的影响程度。对不同均质度、试件尺寸、加载速率下岩石声发射的时序特征进行了研究,同时分析了随机性对声发射各阶段时序特征的影响。结果表明:均质度是随机性影响声发射试验的主要因素。随机性对声发射类型没有影响,但对事件数峰值的影响较大,离散系数大于0.15,而对声发射事件数峰值对应步数影响较小,离散系数小于0.15。声发射计数出现峰值前,随机性对岩石破裂弹性阶段的声发射时序特征的影响最小。

In order to study the influence of randomness on the acoustic emission （AE） sequential characteristics of rock with low homogeneity, numerical simulation software RFPA2D was used to simulate the failure process of rock under uniaxial compression. Through the design of orthogonal test scheme, the impact of randomness on AE sequential characteristics was measured using discrete coefficient of the test results as the evaluation index. The AE sequential characteristics of rock under different homogenization degrees, specimen sizes and loading rates were studied, at the same time, the influence of randomness on the AE sequential characteristics was analyzed. The results showed that the homogeneity was the main factor that affected the randomness of AE test. The randomness had no effect on the AE types, but influenced greatly on peak count, with thedispersion coefficients greater than 0.15. However, the corresponding step number of AE peak was less affected, with thedispersion coefficients less than 0.15. Prior to the peak of AE counts, randomness hadthe minimal effect on the AE sequential characteristics in the elastic phases of rock failure.