To better understand the shear creep characteristics of joints under wetting-drying cycles, multi-stage shear creep experiments are firstly conducted on the joints subjected to different wetting-drying cycles. Then, the shear creep damage characteristics of joints are investigated from the microscopic and macroscopic perspectives through wave velocity tests, scanning electron microscope observations, and failure morphologies. The investigation demonstrates that the increasing wetting-drying cycles lead to a porous and disintegrated microstructure of joints, which further results in increases in the shear deformation and steady-creep rate, and decreases in the failure strength and long-term strength. With increasing wetting-drying cycles, the wear rate of joints decreases and the damaged region of joints becomes smaller and invisible. Furthermore, a classification of the shear creep process of joints containing four stages is firstly proposed based on the test results. It is found that the presence of asperities on the rough joints is the physical basis of the existence of strengthening and cutting stages of the shear creep process. Finally, based on the experimental results, a new fractional-order damage creep model of joints considering wetting-drying cycles is proposed.

为了更好地了解干湿循环下节点的剪切蠕变特性，首先对经历不同干湿循环的节点进行了多阶段剪切蠕变实验。然后，通过波速试验、扫描电子显微镜，从微观和宏观角度研究了接头的剪切蠕变损伤特征。观察和故障形态。研究表明，增加干湿循环会导致接头出现多孔和碎裂的微观结构，进一步导致剪切变形和稳态蠕变速率增加，破坏强度和长期强度降低。随着干湿循环的增加，接头的磨损率降低，接头的损坏区域变得更小并且看不见。此外，首先根据试验结果提出了包含四个阶段的节点剪切蠕变过程的分类。发现粗糙接头上存在的凹凸不平是剪切蠕变过程中存在强化和切割阶段的物理基础。最后，根据实验结果，