Failure characteristics and physical signals of jointed rock: an experimental investigation
Failure characteristics and physical signals of jointed rock: an experimental investigation
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节理岩石的破坏特征和物理信号：实验研究
DOI：
10.1007/s12517-020-05675-2
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发表时间：
2020-07-10
影响因子：
--
通讯作者：
Chen, Liangliang
中科院分区：
文献类型：
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作者：
Wang, Changxiang;Zhang, Shichuan;Chen, Liangliang
节理岩体的稳定性一直是地下工程应用中的热点问题。本研究采用水泥模拟缺陷，对不同缺陷角度的缺陷红砂岩进行了单轴压缩试验。利用应变和声发射方法监测了节理岩体破坏过程中应变和声发射能量的物理特征。试验结果表明，随着缺陷角度的不同，节理岩样的破坏模式发生变化，破坏过程中释放的失稳信号也不同。当缺陷部分的角度较小时，在15°以内，缺陷的破坏模式与完整岩样的破坏模式相似。当缺陷角度在15° ~ 60°之间时，缺陷的破坏模式开始由拉伸破坏向剪切破坏转变。随着缺陷角的增加，节理岩样的破坏过程变得更快，失稳信号的捕获变得更加困难。当缺陷部分的角度小于45°时，通过测量静态亚失稳阶段释放的物理信号，可以确定节理岩样的整体失稳。当缺陷部分的角度增大时，只能根据前一阶段释放的物理信号，即与线性阶段的强烈偏离来确定不稳定性。本文的试验方法可用于节理岩体破坏前兆的识别和岩体工程防灾技术的发展。
Jointed rock mass stability is a constant focus in underground engineering applications. In this study, the uniaxial compression test is carried out on defective red sandstone with different defect angles by using cement to simulate the defects. The physical characteristics of the strain and the acoustic emission energy released during the failure of the jointed rock mass are monitored by means of strain and acoustic emission methods. The experimental results indicate that with the difference in the defect angle, the failure mode of the jointed rock sample changes, and the instability signal released during the failure process is also different. When the angle of the defective part is small, within 15°, the failure modes of the defectsare similar to those of the intact rock sample. When the defect angle is between 15° and 60°, the failure modes of the defects begin to transition from tensile failure to shear failure. With the increase in the defect angle, the failure process of the jointed rock sample becomes faster and it becomes more difficult to capture the instability signal. When the angle of the defect part is smaller than 45°, the overall instability of the jointed rock sample can be determined by measuring the physical signal released in the static sub-instability stage. When the angle of the defect part increases, the instability can only be determined based on the physical signal released from the previous stage, that is, the strong deviation from the linear stage. The experimental method used in this paper could be used to identify failure precursors of jointed rock masses and to develop technology for disaster prevention in rock engineering.