深部非贯通裂隙岩体渗流通道孕育演化机理及渗流特征研究

The inoculation and evolution mechanism of seepage channels in intermittently fractured rock masses under high in situ stress and high osmotic pressure has been one of the key problems to prevent and control water gush disasters in deep underground engineering. By conducting a series of experimental testing including shear-seepage coupling tests, the forming mechanism of seepage channels is revealed firstly, and the promoting mechanism of osmotic pressure on fracture expansion is then clarified. A relationship between seepage channel mode and its corresponding seepage characteristics is established afterwards. Also, a stress-seepage coupling model is put forward of intermittently fractured rock masses. To explain the transformation mechanism of seepage channel mode, a rock bridge failure criterion is specially established with considering the hydro-mechanical coupling effects. Furthermore, on the base of particle flow numerical method the established theoretical model is numerically developed to compute the seepage channel formations in intermittently fractured rock masses. This computing program is utilized to verify the theoretical model and then to predict the seepage characteristics in roadway surrounding rock masses of deep underground coal mine. These aforementioned findings will provide useful theoretical guidance for water disaster prevention and control in deep underground engineering.

高地应力和高渗透水压共同作用下非贯通裂隙岩体渗流通道孕育演化机理是深部地下工程涌水灾害防治的关键科学问题之一。本项目拟开展一系列剪切-渗流耦合试验等试验测试，揭示水力耦合作用下非贯通裂隙岩体渗流通道孕育演化机理，阐明渗透水压对裂隙发展贯通的促进机制，明确渗流通道形成模式与渗流特征相关关系；构建非贯通裂隙岩体应力-渗流耦合分析模型，建立水力耦合作用下岩桥破坏准则，揭示不同渗流通道形成模式及转化机制；基于颗粒流数值方法对理论模型进行数值化开发，建立深部非贯通裂隙岩体渗流通道孕育演化颗粒流数值分析方法，校验理论模型并应用于深部煤矿巷道围岩破坏规律和渗流特征预测评估。项目研究成果可为深部地下工程涌水灾害防治提供理论指导和技术支撑。

高地应力和高渗透水压共同作用下非贯通裂隙岩体渗流通道孕育演化机理是深部地下工程渗水、涌水灾害防治的关键科学问题之一。课题研究紧紧围绕深部地下工程围岩体中“渗流通道的孕育与演化”，开展了一系列剪切-渗流耦合试验等试验测试，首先揭示了开挖卸荷作用下初始剪切裂隙的形成是渗流通道孕育的重要机制；渗流测试研究发现，初始裂隙由于岩桥的阻隔不能成为有效的渗流通道，通过对岩桥破裂的全过程监测阐明了渗流通道的演化过程。在剪切-渗流耦合作用下，岩桥的破裂机理主要分为张拉破坏（T模式）、剪切破坏（S模式）和混合破坏(M模式)，并根据破裂后岩桥裂隙的形态特征分为T1通道、T2通道、S1通道、S2通道、M1通道和M2通道等6种不同通道类型；在此基础上，通过理论分析构建了非贯通裂隙岩体应力-渗流耦合分析模型，建立了水力耦合作用下岩桥的破坏准则，并讨论了不同渗流通道形成模式及其相互转化机制。项目研究成果对于深部地下工程围岩体内渗流裂隙网络的演化预测具有指导意义，为深部地下工程渗水、涌水灾害的防治提供理论指导和技术支撑。项目按计划完成，共发表论文9篇，申请发明专利5项，协助培养了博士和硕士研究生各1名。