高应力、高水压下深部岩体单裂隙渗流-应力耦合作用研究

The coupling of Seepage and stress fields in jointed rock mass is confronted frequently in many geotechnical situations such as water conservation, hydropower, high-level radioactive waste disposal, oil reposition and slope engineering. Hydro-mechanical characteristic of fractured rock mass under high stress and seepage pressure is one of important scientific problems that need to be solved in the utilization and improvement of deep fractured rock masses. A series of seepage testing under high stress (normal stress, two-dimensional stress and true triaxial stress) and high seepage pressure on single fractured rock mass will be carried out. Based on the above experimental result, the dynamic evolution law of permeability coefficient, the filling degree、roughness and deformation of fracture, which were affected by the different stress(tensile stress, compressive stress and shear stress) in single fracture surface, will be investigated. According to engineering geology, rock mechanics, seepage mechanics and nonlinear mechanics, the seepage - stress coupling constitutive model of single fractured rock mass will be developed. Finally, a new numerical simulation approach about the seepage-stress coupling of single fractured rock mass under high stress and high seepage stress is proposed, the seepage-stress coupling mechanism of single fractured rock mass is revealed further. The research results will not only provide theoretical basis and technical support for seepage analysis and stability evolution of deep rock engineering, but also serve as guidance on deepening the understanding of rock mass hydraulics and controlling geotechnical engineering disasters.

高应力、高水压下岩体裂隙渗流-应力耦合作用特性是深部岩体利用与改造过程中亟待解决的关键科学问题。针对处于三向高应力、高水压的深部裂隙岩体，本项目拟通过开展不同高应力（法向应力、二维应力和真三轴应力）、不同高水压条件下深部岩体单裂隙面的渗流试验，调查单裂隙面上不同应力状态（拉应力、压应力和剪应力）与裂隙渗透系数、填充度、粗糙度和变形的动态演化影响规律。综合运用工程地质学、岩石力学、渗流力学、非线性力学等理论，建立高应力、高水压条件下岩体单裂隙渗流-应力耦合作用的本构模型。最后，借助有限元分析软件，提出高应力、高水压下岩体单裂隙渗流-应力耦合作用过程的数值模拟新方法，揭示复杂高应力和高水压条件下岩体单裂隙渗流-应力耦合作用机理。研究成果可为深部岩石工程渗流分析与稳定性评价提供理论基础和技术支撑，同时对于提高深部岩体水力学的认识和遏制深部岩土工程灾害的发生具有指导意义。

高应力、高水压下岩体裂隙渗流-应力耦合作用特性是深部岩体利用与改造过程中亟待解决的关键科学问题。针对处于三向高应力、高水压的深部裂隙岩体，本项目利用研制的真三轴岩石裂隙渗流实验装置开展了一系列岩体单裂隙在真三向高应力和高水压作用下的渗流实验，有效解决了大尺寸试件剪切位移下的渗流密封难题，实现了真三向高应力下岩体裂隙变形与渗流耦合试验过程中裂隙变形与渗透系数的精确测量。基于试验结果，分析了岩体单裂隙面上不同应力状态（拉应力、压应力和剪应力）与裂隙渗透系数、粗糙度和变形的动态演化影响规律。综合运用工程地质学、岩石力学、渗流力学、非线性力学等理论，建立了高应力、高水压条件下岩体单裂隙渗流-应力耦合作用理论模型，揭示了复杂高应力和高水压条件下岩体单裂隙渗流-应力耦合作用机理。研究成果为深部岩石工程渗流分析与稳定性评价提供理论基础和技术支撑，同时对于提高深部岩体水力学的认识和遏制深部岩土工程灾害的发生具有科学意义。