岩石的细胞元特性及其非均质分布对岩石全曲线性态的影响

INFLUENCE OF ROCK CELL CHARACTERISTICS AND ROCK INHOMOGENEITY PARAMETER ON COMPLETE CURVE OF STRESS-STRAIN

采用非均质数值试验方法,研究了在无限大刚度的试验机条件下,岩石的细胞元特性及其非均质分布对岩石单轴压缩全程曲线性态的影响。结果表明,当岩石的非均质参数m≥6时,细胞元的非均质参数m是决定岩石单轴压缩全程曲线性态的主要因素;当m<6时,岩石的细胞元特性是决定岩石单轴压缩全程曲线性态的主要因素。

Through numerical experiment method, the influence of rock cell characteristics and rock inhomogeneity parameter on the character of the complete stress-strain curve under uniaxial compression is studied with rigid testing machine. Rock cell characteristics reflect the relationship between stress and strain, such as pure-elasticity, elasto-plasticity, strain-softening and strain-hardening. The material in each element is treated as homogeneous and is not the same as other element. The elastic constants and failure strength are randomly assigned according to Weibull distribution. The inhomogeneity parameter m reflects the initial heterogeneity of distribution of material properties. The study result indicates that rock inhomogeneity parameter, m, is the decisive factor of complete curve character under uniaxial compression with m≥6. On the contrary, with m<6, the rock cell characteristics are the decisive factor of complete curve character under uniaxial compression. The difference between peak and residual strength of rock sample is increased with the difference of corresponding rock cell.