Mud and water bursts within fault fracture zone frequently lead to casualties, equipment damage, and project delays, posing significant risks. A thorough scientific understanding of these mechanisms is essential for effective disaster prevention and control. To investigate the evolution mechanisms of mud and water burst in fault fracture zones, an experimental apparatus was designed to simulate the migration and loss of filling material particles under triaxial loading conditions. Experiments conducted with this apparatus explored the evolution process of mud and water bursts under varying initial dry densities. The results demonstrate that the evolution of mud and water bursts is a complex process, characterized by increased porosity and permeability, decreased strength, and fluctuating viscosity. The initial dry density plays a critical role in determining the failure mode of mud and water bursts. At low initial dry densities, the filling material is prone to seepage failure. In contrast, at high initial dry densities and elevated water pressures, the material is more likely to experience splitting failure. In comparison to seepage failure, the evolution process of splitting failure exhibits a significant delay, with a longer incubation period. However, it can rapidly form seepage channels in a short time, leading to more severe mud and water bursts. Finally, the study analyzed variations in porosity, permeability, and shear strength associated with different failure modes. Generalized models were established to describe the evolutionary characteristics of both seepage and splitting failure. These findings offer valuable insights for improving the safety and stability of tunnel engineering in environments prone to such risks.

中文翻译：

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初始干密度对断层断裂带泥浆、突水演化机制的影响：一系列试验研究


断层断裂带内的泥浆和水爆经常导致人员伤亡、设备损坏和项目延误，构成重大风险。对这些机制的透彻科学理解对于有效的灾害预防和控制至关重要。为研究断层断裂带泥浆和水爆发的演化机制，设计了一种实验装置来模拟三轴加载条件下填充材料颗粒的迁移和损失。使用该仪器进行的实验探索了泥浆和水爆发在不同初始干密度下的演变过程。结果表明，泥浆和水爆的演变是一个复杂的过程，其特征是孔隙率和渗透性增加、强度降低和粘度波动。初始干密度在确定泥浆和水爆裂的破坏模式中起着关键作用。在较低的初始干密度下，填充材料容易发生渗流失败。相比之下，在较高的初始干密度和较高的水压下，该材料更有可能发生劈裂失效。与渗流破坏相比，分裂破坏的演化过程表现出明显的延迟，潜伏期更长。然而，它可以在短时间内迅速形成渗流通道，导致更严重的泥浆和水爆裂。最后，该研究分析了与不同失效模式相关的孔隙率、渗透率和剪切强度的变化。建立了广义模型来描述渗流和劈裂破坏的进化特征。这些发现为在容易发生此类风险的环境中提高隧道工程的安全性和稳定性提供了有价值的见解。