Abstract:Several typical stress threshold stages exist for rock materials during uniaxial compressive deformation failure process. It can help us to understand the mechanical behavior of internal crack propagation and rock failure mechanism in the progressive failure process. Two parameters,crack radial area strain and crack axial strain,are introduced based on the crack volumetric strain method in this paper. By conducting uniaxial compressive tests on five kinds of rocks,the proposed method and acoustic emission monitoring method are used to identify the stress thresholds of the five kinds of rock under uniaxial compression. According to the slope of the crack radial area strain curve when the rock breaks,the rock types are classified into type I and type II rocks. The testing results indicate that the stress threshold can be well identified by using the axial crack strain and radial area strain of the crack for type I and type II rocks respectively. It can accurately identify the stable crack development stress ,crack instability development stress ,and the crack connectivity stress of rock. Meanwhile,the results are similar to the stress threshold identified by the acoustic emission method. The mismatching phenomenon of stress thresholds identified by volumetric strain method,crack volumetric strain method and acoustic emission method is explained reasonably,the consistency of stress thresholds identification results using stress and strain data and acoustic emission data in the process of rock compression is realized.
李地元,陈昱达. 单轴压缩下岩石裂纹扩展应力阈值识别与验证[J]. 岩石力学与工程学报, 2023, 42(S1): 3121-3130.
LI Diyuan,CHEN Yuda. Identification and verification of stress threshold for rock crack propagation under uniaxial compression. , 2023, 42(S1): 3121-3130.
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