三向应力作用下节理岩体渗流-应力耦合特性

节理岩体渗流-应力耦合特性研究是岩石力学领域的重点和难点。水利水电工程与地下工程中天然节理岩体往往处于三向不等压应力状态，针对三向应力状态下节理岩体渗流-应力耦合特性研究较少。其中，单节理岩体渗流-应力耦合特性研究是基础。首先分析与探究了单节理岩体侧向应力作用效果及渗流作用机制，在单节理岩体渗透性-应力耦合分析模型基础上推导了单节理岩体渗流-应力耦合的理论公式。通过室内真三轴渗流-应力耦合试验，基于全局优化算法的非线性拟合及块体离散元数值仿真，验证了所提出理论公式的合理性。基于电路原理，给出了模拟电路与渗流问题的相似物理量，通过引入等效渗流阻方法，探究了典型的含正六边形主干节理网络的渗流-应力耦合特性。该研究结果对实际工程岩体的渗流分析有一定的参考价值。

Stress-seepage coupling characteristics of jointed rock mass under three principal stresses

The topic on the seepage-stress coupling characteristics of jointed rock mass is generally considered as an important and difficult research direction in the field of rock mechanics. The natural jointed rock mass commonly exists in the three unequal compressive stress states in water conservancy and hydropower engineering and underground engineering. There are limited studies on the seepage-stress coupling characteristics of jointed rock mass under the states of three principal stresses. The fundamental study should focus on the seepage-stress coupling characteristics of the monolithic rock mass. In this study, the effect of lateral stress and the seepage mechanism of monolithic rock mass were analysed and explored. Then the theoretical formula of its seepage-stress coupling characteristics was deduced on the basis of the existing permeability-stress analytical model. Theoretical results were also compared with experimental results from true triaxial seepage-stress coupling tests in the laboratory. The rationality of the derived formula was verified by the global optimisation nonlinear fitting method and the block discrete element method (DEM). The similar physical quantities of analog circuits and seepage problems were obtained by using the circuit principle. The seepage-stress coupling characteristics of jointed rock mass with a regular hexagonal joint network were preliminarily investigated by introducing the equivalent seepage resistance method. The obtained results provide useful references for seepage analysis of rock mass in practical engineering.