The fatigue damage mechanical behaviours of rock joints under pre-peak cyclic shear loading are one of the key factors affecting the dynamic stability of slopes. In this study, the macro-meso fatigue damage mechanism of rock joints with multiscale asperities, when considerthe influence of the normal stress, shear rate, shear amplitude, first-order asperity angle, number of shear cycles and joint morphology, were investigated using experimental and numerical approaches under a constant normal load (CNL). The laboratory pre-peak cyclic shear experiments on the saw-tooth rock joints with different first-order asperity angles, i.e., 30°, 45° and 60°, and the same second-order asperity angle of 45°, were first conducted under different influence factors mentioned above. Six evolution stages of the shear stress with the shear displacement, i.e., initial nonlinear shear contraction deformation, approximate linear elastic shear dilation deformation, cyclic fatigue damage deformation, plastic deformation of the local compression-shear fracture, full plastic deformation of the stress brittle drop and ideal plastic flow deformation, were obtained. Additionally, the variation rules of the influence factors mentioned above with the peak (and residual) shear strengths and the cumulative shear (and normal) displacements were explored. Subsequently, the PFC^2D discrete element method was used for the meso numerical simulations, in which the meso fatigue damage evolution processes of the saw-tooth and wavy rock joints were simulated considering more number of shear cycles. Meanwhile, the change rules of the meso fatigue damage crack number (and energy) with the shear displacement (and the number of cycles), and the distribution characteristics of the meso fatigue damage particles were observed. Based on the good agreement between the macro experimental results and the meso numerical observations, the macro-meso fatigue damage failure modes of rock joints can be generally summarized as three basic types, i.e., compacting – climbing failure mode, climbing – cyclic abrading – extruding – gnawing failure mode and gnawing – sliding failure mode.

峰前循环剪切荷载作用下岩石节理的疲劳损伤力学行为是影响边坡动力稳定性的关键因素之一。本研究综合考虑法向应力、剪切速率、剪切幅值、一阶粗糙角、剪切循环次数和节理形态的影响，研究了多尺度粗糙岩石节理的宏观-细观疲劳损伤机制。和恒定法向载荷 (CNL) 下的数值方法。首次对不同一阶粗糙度角（即30°、45°和60°）和相同的二阶粗糙度角45°的锯齿状岩石节理进行室内峰前循环剪切试验。上面提到的不同的影响因素。剪切应力随剪切位移的六个演化阶段，即，得到了初始非线性剪收缩变形、近似线弹性剪胀变形、循环疲劳损伤变形、局部压剪断裂塑性变形、应力脆降全塑性变形和理想塑性流动变形。此外，还探讨了上述影响因素与峰值（和残余）剪切强度和累积剪切（和法向）位移的变化规律。随后，PFC 探讨了上述影响因素与峰值（和残余）剪切强度和累积剪切（和法向）位移的变化规律。随后，PFC 探讨了上述影响因素与峰值（和残余）剪切强度和累积剪切（和法向）位移的变化规律。随后，PFC细观数值模拟采用^二维离散元方法，在考虑更多剪切循环次数的情况下，模拟锯齿状和波浪状岩石节理的细观疲劳损伤演化过程。同时，观察细观疲劳损伤裂纹数（和能量）随剪切位移（和循环次数）的变化规律，观察细观疲劳损伤粒子的分布特征。基于宏观实验结果与细观数值观察结果的较好吻合，岩石节理宏观-细观疲劳破坏破坏模式大致可概括为三种基本类型，即压实-爬坡破坏模式、爬坡-循环磨损-挤压破坏模式。 – 咬合故障模式和咬合故障模式。