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岩石材料的宏观力学特征是材料内部细观力学特性的综合反映。对于脆性岩石材料,其内部的非均匀性对材料的宏观破坏形式有着重要的影响。应用演化细胞自动机方法(ECA)对岩石的非均匀性进行了初步的探讨。该方法以位移、力、应力和应变等矢量和张量作为系统的基本变量,定量计算了反映岩石破坏过程中应力集中以及应力重新分布的过程。在宏观上则认为脆性岩石材料是一种非均匀性材料,并假定脆性岩石材料的非均匀性符合Weibull分布,坡度参数m是Weibull分布中的反映分布非均匀程度的重要参数。通过对符合Weibull分布中不同坡度参数的脆性岩石材料进行数值模拟试验,发现由Weibull分布中的坡度参数表示的非均匀性是影响脆性岩石材料破坏方式的重要因素,材料的坡度参数越小,材料越不均匀,其破坏形式则越具有随机性;材料的坡度参数越大,材料越趋于均匀,其破坏形式越具有规则性,即趋于弹性材料的破坏形式,这与试验结果是吻合的。
The macroscopic mechanical characteristics of rock materials are the comprehensive reflection of meso-mechanical properties of materials. For brittle rock materials, the internal heterogeneity has an important influence on the macroscopic failure mode of materials. The heterogeneity of rock has been preliminarily studied by the method of evolutionary cell automata (ECA). In this method, vectors and tensors such as displacement, force, stress and strain are taken as the basic variables of the system, and the process of stress concentration and stress redistribution in the process of rock failure is quantitatively calculated. Macroscopically, the brittle rock material is considered as an inhomogeneous material, and it is assumed that the non-uniform brittle rock material meets the Weibull distribution. The slope parameter m is an important parameter reflecting the non-uniform distribution in the Weibull distribution. By numerical simulations of brittle rock materials that conform to different slope parameters in Weibull distribution, it is found that the inhomogeneity indicated by the slope parameter in Weibull distribution is an important factor affecting the failure mode of brittle rock materials. The smaller the slope parameter of materials, The more non-uniform, the more destructive the form is, the more random the material is. The greater the slope parameter of the material, the more uniform the material, the more regular the damage form, that is to tend to the destruction form of the elastic material, which agrees with the test result .