The mechanical behavior and permeability evolution of saturated hard rock are significantly important to the stability and safety of super-high arch dams. A series of triaxial compression tests were conducted on amygdaloidal basalt under different pore pressures. Based on the experimental results, a micromechanical-based elastoplastic damage model is proposed for such saturated hard rock. The hydromechanical coupling is formulated using the thermodynamic framework for saturated media. Damage is induced by the growth of microcracks and the plastic deformation is related to the frictional sliding between rough crack surfaces. The thermodynamic forces associated with damage and plasticity are deduced with a special thermodynamic potential for saturated hard rocks. New plastic and damage criteria are proposed to describe the evolutions of the internal variables. The permeability evolution is estimated by the volumetric averaging of the local permeability in microcracks. The developed models were calibrated and validated by a series of triaxial compression tests on saturated hard rocks. The main mechanical behaviors and permeability evolution properties of saturated hard rock are well captured by the proposed model.

中文翻译：

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饱和硬岩弹塑性损伤与渗透率耦合试验研究与数值模拟

饱和硬岩的力学行为和渗透率演化对特高拱坝的稳定性和安全性具有重要意义。在不同孔隙压力下对杏仁状玄武岩进行了一系列三轴压缩试验。基于试验结果，针对此类饱和硬岩，提出了一种基于微观力学的弹塑性损伤模型。流体力学耦合是使用饱和介质的热力学框架制定的。损伤是由微裂纹的生长引起的，塑性变形与粗糙裂纹表面之间的摩擦滑动有关。与损伤和塑性相关的热力学力是通过饱和硬岩的特殊热力学势推导出来的。提出了新的塑性和损伤准则来描述内部变量的演变。渗透率演化是通过微裂缝中局部渗透率的体积平均来估计的。开发的模型通过对饱和硬岩的一系列三轴压缩试验进行校准和验证。所提出的模型很好地捕捉了饱和硬岩的主要力学行为和渗透率演化特性。