Water effects on the mechanical properties of rocks have been extensively investigated through experiments and numerical models. However, few studies have established a comprehensive link between the microscopic mechanisms of water-related micro-crack and the constitutive behaviors of rocks. In this work, we shall propose an extended micromechanical-based plastic damage model for understanding weakening effect induced by the presence of water between micro-crack’s surfaces on quasi-brittle rocks, based on the Mori-Tanaka homogenization and irreversible thermodynamics framework. Regarding the physical mechanism, water strengthens micro-crack propagation, which induces damage evolution during the pre- and post-stage, and weakens the elastic effective properties of rock matrix. After proposing a special calibration procedure for the determination of model parameters based on the laboratory compression tests, the proposed micromechanical-based model is verified by comparing the model predictions to the experimental results. The model effectively captures the mechanical behaviors of quasi-brittle rocks subjected to the weakening effects of water.

中文翻译：

---

一种扩展的基于微力学的塑性损伤模型，用于了解水对准脆性岩石的影响


人们通过实验和数值模型广泛研究了水对岩石力学性能的影响。然而，很少有研究在与水相关的微裂纹的微观机制与岩石的本构行为之间建立全面的联系。在这项工作中，我们将基于 Mori-Tanaka 均质化和不可逆热力学框架，提出一种扩展的基于微力学的塑性损伤模型，用于理解准脆性岩石微裂纹表面之间存在水引起的弱化效应。从物理机制来看，水强化了微裂纹扩展，诱发前后阶段损伤演化，削弱了岩石基质的弹性有效性能。在提出基于实验室压缩测试确定模型参数的特殊校准程序后，通过将模型预测与实验结果进行比较来验证所提出的基于微力学的模型。该模型有效地捕捉了准脆性岩石在水弱化作用下的力学行为。