Investigating the progressive fracture process of rock masses containing flaws holds significant importance for assessing the stability of rock engineering projects. To study the fracture evolution behaviors of rocks with pre-existing flaws, uniaxial compression tests are carried out on red sandstone specimens containing two parallel flaws with different ligament angles (β). Two monitoring techniques, including acoustic emission (AE) and high-speed camera, are utilized to capture the cracking process of flawed rocks. This investigation primarily examines the effect of β on the mechanical properties of flawed rocks. Subsequently, the fracture progression in these rocks is characterized using the interevent time function F(τ), which represents the rate of AE events. It is evident that the initiation, coalescence, and failure modes of flawed rocks are notably influenced by β. Furthermore, we employed fractal theory to explore the fractal characteristics of flawed rocks; thereby, enhancing our assessment of their fracture damage process. Two parameters derived from fractal analysis, including correlation dimension D and its change rate η, can be served as the damage indicators to characterize the fracture process of flawed rocks. D varies from 1.5 to 5 in the absence of macrocracking. Although it ranges from 0.5 to 0.7 during macrocracking occurrences. Ultimately, D approaches near-zero levels upon reaching ultimate failure. Notably, η displays a substantial increase beyond 0% when macrocracking occurs. The sharp decline in D and the rapid ascent in η can be considered crucial early warning indicators for the onset of macrocracking in flawed rocks.

研究含缺陷岩体的渐进破裂过程对于评估岩石工程项目的稳定性具有重要意义。为研究含预存缺陷岩石的断裂演化行为，对含有两条不同韧带角（ β）平行缺陷的红砂岩试件进行单轴压缩试验。利用声发射（AE）和高速摄像机两种监测技术来捕捉有缺陷岩石的破裂过程。这项研究主要研究β对有缺陷岩石力学性能的影响。随后，使用事件间隔时间函数F ( τ )来表征这些岩石中的断裂进展，该函数代表 AE 事件的发生率。显然，有缺陷岩石的引发、合并和破坏模式显着受β 的影响。进一步利用分形理论探讨了有缺陷岩石的分形特征；从而加强我们对其断裂损伤过程的评估。分形分析得出的两个参数，即相关维数D及其变化率η，可以作为表征有缺陷岩石破裂过程的损伤指标。在没有宏观裂纹的情况下，D 的变化范围为 1.5 至 5。尽管在发生宏观裂纹时其范围为 0.5 至 0.7。最终，D在达到最终失败时接近于零水平。值得注意的是，当发生宏观裂纹时， η显示出超过 0% 的大幅增加。D的急剧下降和η 的快速上升可以被认为是有缺陷岩石中宏观裂纹开始的关键预警指标。