单轴压缩条件下消落带岩体应变及声发射特性研究*

为掌握消落带岩体在加载过程中其应力-应变和声发射特性,分析其变形破坏过程中各阶段的阈值,在单轴压缩、有CT断面扫描的辅助条件下,运用MST岩石力学试验系统和PAC声发射信号采集处理系统,对消落带3个高程岩体进行试验测试。获得了岩石轴向应力与轴向应变、横向应变和体应变之间的关系特征曲线,以及加载过程中压密、启裂、损伤(破坏)各阶段的声发射信号数量、能量(振幅)等特征。两方法均可得到试件启裂、损伤阈值和峰值强度,但结果有一定差异性。通过两方法联合分析,可预判其岩体启裂强度和损伤强度分别为峰值强度的0.4倍左右和0.8倍左右。试验间接反映出消落带岩体改造强烈程度中部区域大于顶部和底部区域,与实际情况较一致。

Research on Strain and Acoustic emission characteristics of rock mass under uniaxial compression in the Water level-fluctuating zone

In order to grasp the stress - strain and acoustic emission characteristics of rock mass in the process of loading, analysis of the various stages of the process of deformation and failure threshold. Under the condition of single axis compression and CT section scanning, using MST rock mechanics test system and PAC acoustic emission signal acquisition and processing system, test on the rock mass of three vertical in the fluctuating zone. The relationship of axial stress with strain, transverse strain and volume strain of rock and the loading process in different stages of the medium pressure dense, and crack, damage, the number of acoustic emission signal energy (amplitude) and other characteristics, both methods are available specimens and crack, damage threshold and peak intensity, but the results have certain differences. Combined analysis by two methods, can predict the crack strength and damage strength of rock mass, respectively 0.4 times and 0.8 times of the peak intensity. Test indirectly reveal down with strong reformation degree of rock mass, The middle area is more serious than the area at the top and bottom, consistent with the actual situation.