The shearing characteristics of rock joints govern the mechanical performance of discontinuous rock masses. The present study investigated the normal compression and shear behavior of rock joints through cyclic compression tests and direct shear tests. The irreversible relationship between the normal stress and the normal closure was confirmed by cyclic compression tests on rock joints. An elastoplastic model was proposed incorporating the aperture variation. A modified version of the critical state framework was developed for modeling the shearing and dilation behavior. Specifically, the initial state of the rock joints was determined according to the stress history. The proposed model for the mechanical behavior of rock joints was validated by predicting the experimental results. A parameter analysis was also performed to highlight the difference in the shear behavior of the rock joints due to the difference in the initial apertures.

节理的剪切特性决定了不连续岩体的力学性能。本研究通过循环压缩试验研究了岩石节理的正常压缩和剪切行为，并直接剪切试验。岩石节理的循环压缩试验证实了正应力与正闭合之间的不可逆关系。提出了一种结合孔径变化的弹塑性模型。开发了临界状态框架的修改版本，用于对剪切和膨胀行为进行建模。具体而言，根据应力历史确定岩石节理的初始状态。通过对实验结果的预测，验证了所提出的岩石节理力学行为模型。还进行了参数分析，以突出由于初始孔径不同而导致的岩石节理剪切行为的差异。