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Abstract：
With regard to deep mining in metal mines, an investigation into the failure mode of deep fractured rock masses and their corresponding acoustic emission signal characteristics is conducted via uniaxial compression tests. Subsequently, a fractal damage renormalization group mechanical model is developed to explain the behavior of those fractured rock masses. Employing the bonded block model (BBM) numerical simulation method, fracture process in synthetic rock samples is analyzed, thereby validating the efficacy of the mechanical model. The numerical simulations highlight the critical role of fractures expansion in underlying the deterioration of rock mass strength. As the peak load decreases, the fracture fractal dimension increases, leading to a significant 14.2% reduction in compressive strength accompanied by an approximate 8.7% rise in average fracture fractal dimension. A comparative analysis of tetrahedral and voronoi block synthetic rock samples reveals the tetrahedral block samples exhibit a superior ability to depict the fracture behavior of fractured rock masses. Specifically, they offer a more accurate simulation of acoustic emission characteristics and failure modes. Furthermore, variations in the fracture fractal dimension with respect to the hole defect\'s position are observed, with the maximum value occurring along the vertical axis of the hole defect. This observation underscores the potential utility of visually monitoring deep rock fracture dynamics as an effective mean for quantitatively evaluating fracture damage and strength degradation in deep rock formations.
摘要：
关于金属矿的深部开采,通过单轴压缩试验，对深部裂隙岩体的破坏模式及其相应的声发射信号特征进行了研究。随后，建立了分形损伤重整化组力学模型来解释这些裂隙岩体的行为。采用粘结块模型(BBM)数值模拟方法，分析了合成岩石样品的断裂过程，从而验证了力学模型的有效性。数值模拟强调了裂缝膨胀在岩体强度劣化中的关键作用。随着峰值负荷的减小,裂缝分形维数增加，导致抗压强度显著降低14.2%，同时平均断裂分形维数上升约8.7%。对四面体和Voronoi块合成岩石样品的比较分析表明，四面体块样品具有出色的描绘裂隙岩体破裂行为的能力。具体来说,他们提供了一个更准确的模拟声发射特性和失效模式。此外，观察到裂缝分形维数相对于孔缺陷位置的变化，最大值出现在孔缺陷的垂直轴上。这一观察结果强调了视觉监测深部岩石断裂动力学作为定量评估深部岩层断裂损伤和强度退化的有效手段的潜在效用。
