论文部分内容阅读
对含原生隐裂隙的玄武岩试样开展单轴压缩试验,并同步采集岩样变形破坏过程中的声发射信息,结合试样的结构特征对试验结果进行系统分析,研究结果表明:(1)隐裂隙影响试样的压缩破坏特征,试样受原生隐裂隙的切割,其压缩变形破坏模式为隐裂隙尖端裂纹的扩展、裂隙面之间的剪切滑移以及由裂隙面剪切变形而引起张拉破裂等构成的剪切–张拉型变形破坏模式。(2)受原生隐裂隙的影响,试样在变形破坏阶段,应力–应变曲线呈“锯齿”状;(3)含隐裂隙的玄武岩天然平均单轴抗压强度为106 MPa,低于同场地完整的隐晶质玄武岩;且试样中隐裂隙越发育,其强度越低;(4)加卸载过程中,不同类型的变形所引发的声发射信号特征不一样,永久应变所引发的声发射信号幅值比弹性应变所引发的高;(5)试样在破坏之前,内部破裂较少,声发射数保持平稳,进入变形破坏阶段后,声发射数激增;试样中的隐裂隙对声发射能量具有吸收效应,而当隐裂隙闭合时,吸收效果减弱。
Uniaxial compression tests were carried out on the basalt samples containing primary cryptocorrosion and the acoustic emission information during the deformation and destruction of the samples was acquired synchronously. The experimental results were systematically analyzed according to the structural characteristics of the samples. The results show that: (1) The fracture affects the compressive failure characteristics of the specimen. The specimen is cut by the primary fractured fracture. The compressive deformation failure mode is the crack propagation at the crack tip, the shear slip between the fracture surfaces and the shear deformation caused by the fracture surface Pull-rupture, etc. constitute the shear - tension-type deformation failure mode. (2) Due to the influence of primary fissures, the stress-strain curves of the specimens are “zig-zag” in the stage of deformation and failure. (3) The natural uniaxial compressive strength of basalt with fissures is 106 MPa, (4) During the process of loading and unloading, the characteristics of acoustic emission signal caused by different types of deformation are different, and the strain caused by permanent strain The acoustic emission signal amplitude is higher than that caused by elastic strain; (5) Before the failure, internal rupture is less and the number of acoustic emission remains stable. After entering the stage of deformation and failure, the number of acoustic emission increases sharply; It has an absorption effect on the energy of acoustic emission. When the hidden fracture is closed, the absorption effect is weakened.