The slip shear failure along rock discontinuities is one of the predominant failure modes of landslides. To simulate impact shear loads during landslide and rockburst, an experimental method is presented to achieve the dynamic shear load in a direct shear testing configuration. The dynamic loading system is derived from the SHPB methodology and can provide high shear velocities around 1–10 m/s. Dynamic direct shear experiments on rough rock discontinuities are conducted by using a dynamic shear apparatus combined with a high-speed digital camera. The effects of shear velocity and normal stress on the slip displacement, slip velocity and slip acceleration of rough rock discontinuities are analyzed using a two-dimensional digital image correlation (DIC) technique. It is observed that the rate of the slip is linearly proportional to the shear velocity and decreases with the increasing normal stress. Using the DIC method, the strain at failing asperities is calculated as a function of the shear velocity and the normal stress. The micro-structural characteristics of the shear zone formed in the slip failure is examined to understand the slip failure mode. Moreover, the dynamic viscous is added to the static Barton's shear strength criterion and the damage evolution occurred at the asperities due to the dynamic loading is introduced by means of a damage control parameter D. Thereafter, a dynamic failure criterion is developed by considering both surface roughness and dynamic loading. The failure model can provide a good prediction of the experimental data, indicating that the proposed models can describe well the dynamic shear process of rock discontinuities under high velocity impact.

沿岩石不连续面的滑动剪切破坏是滑坡的主要破坏模式之一。模拟滑坡和岩爆期间的冲击剪切载荷，提出了一种在直接剪切测试配置中实现动态剪切载荷的实验方法。动态加载系统源自 SHPB 方法，可以提供大约 1-10 m/s 的高剪切速度。利用动态剪切仪结合高速数码相机对粗糙岩石不连续面进行动态直剪试验。使用二维数字图像相关 (DIC) 技术分析剪切速度和法向应力对粗糙岩石不连续性的滑动位移、滑动速度和滑动加速度的影响。观察到滑移率与剪切速度成线性正比，并随着法向应力的增加而减小. 使用 DIC 方法，可将失效粗糙处的应变计算为剪切速度和法向应力的函数。检查滑动破坏中形成的剪切带的微观结构特征以了解滑动破坏模式。此外，动态粘性被添加到静态巴顿剪切强度准则中，并且通过损伤控制参数D引入了由于动态载荷而在粗糙处发生的损伤演变。此后，通过考虑表面粗糙度和动态载荷，开发了动态失效准则。该破坏模型对实验数据具有较好的预测性，表明所提出的模型能够很好地描述高速冲击下岩石不连续性的动态剪切过程。