单轴压缩和劈裂试验下不同岩性岩石声发射特性研究

为研究不同岩石声发射特性,选取均质、节理裂隙不发育的白砂岩、大理岩和花岗岩3类完整岩样和不均质、节理裂隙发育的现场岩样为试验对象,进行单轴压缩和巴西劈裂试验,研究拉-压作用下不同岩石声发射特征的差异性。结果表明,在单轴压缩试验下,完整岩样声发射参数特征与岩石强度密切相关,花岗岩破坏所释放的累积AE能量明显大于白砂岩和大理岩;现场岩样各声发射参数最大值则与岩石强度关联性不大。完整岩样和现场岩样的动态b值基本分布范围在1~4之间,且整体呈先上升中间波动随后回落的变化规律。岩石加载整个过程中的声发射特征与岩石均质程度和节理发育情况密切相关。

Study on AE Characteristics of Different Lithology Rocks under Uniaxial Compression and Brazilian Split Tests

For studying the acoustic emission(AE) characteristics of different lithology rocks,three kinds of homogeneous and joint fissure underdevelopment different lithology intact rocks of white sandstone,marble and granite,and the heterogeneity and joint fissure development engineering rocks are selected as the research object to analyze the AE characteristics of rocks with tension-compression under uniaxial compression and Brazilian split tests.The results show that,the AE parameters signatures of intact rocks are closely related to the rock strength,and the cumulative AE energy released by granite failure is obviously greater than that of white sandstone and marble under uniaxial compression test.Additionally,the maximum value of AE parameters of engineering rocks has little correlation with rock strength.The distribution range of dynamic b value of intact rocks and engineering rocks is between 1 and 4,and the overall change rule is that it rises first,fluctuates in the middle and then falls down.It is found by comparing results that the degree of rock homogeneity and the state of joint development have obvious influence on the AE characteristics in the whole process of rock loading.