含裂纹缺陷脆性岩石的峰值强度模型

Peak strength model of brittle rocks containing flaws

在分析Ashby和Hallam含缺陷脆性介质峰值强度理论模型基础上,对其进行修正,并用修正的理论模型研究单轴作用下,含裂纹缺陷花岗岩试样的裂纹萌生、扩展、贯通和相互作用等因素对峰值强度的影响规律。通过与物理试验和数值模拟结果对比分析发现:修正后的Ashby-Hallam强度模型能定量地预测含缺陷岩石的峰值强度,以及定性分析峰值强度同裂纹缺陷密度和裂纹贯通密度的关系;含裂纹缺陷脆性岩体的峰值强度主要与贯通的裂纹数以及缺陷的分布和缺陷大小有关。

A modified Ashby-Hallam model was used to calculate the peak strength of granite specimens containing flaws. The model considers the influence of crack initiation, propagation, coalescence, and interaction on the peak strengths of the granite specimens containing flaws under uniaxial compression. Comparison of theoretical and experimental results shows that the modified Ashby-Hallam model accurately predicts the peak strength of granite specimens containing flaws as a function of the defect density and the coalescence density. The two main factors that affect the peak strength of brittle rocks containing flaws are the coalescence densitys for which reductions increase the peak strength and the distribution and size of the flaws.