Rock blocks sliding along discontinuities can cause serious disasters, such as landslides, earthquakes, or rock bursts. The shear rate-dependent behavior is a typical time-dependent behavior of a rock discontinuity, and it is closely related to the stability of a rock block. To further study the shear rate-dependent behavior of rock discontinuities, shear tests with alternating shear rates (SASRs) were conducted on rock discontinuities with various surface morphologies. The dynamic evolution of the shear rate dependency was studied in detail based on the shear test results, and three stages were identified with respect to the shear stress and shear deformation states. The test results revealed that dynamic changes in shear stiffness and the energy storage abilities of the rock discontinuities occurred in relation to the shear rate-dependent behavior of crack growth, which increased with an increase in normal stress and/or the joint roughness coefficient. The stage of decreasing shear stiffness corresponded to a stage of noticeable shear rate-dependency, and the shear rate was found to have no influence on the initial crack stress.

沿不连续点滑动的岩块会导致严重的灾害，例如滑坡、地震或岩爆。剪切速率相关行为是岩石间断面的典型时间相关行为，与岩块的稳定性密切相关。为了进一步研究岩石不连续性的剪切速率相关行为，对具有各种表面形态的岩石不连续性进行了交替剪切速率 (SASR) 的剪切试验。根据剪切试验结果详细研究了剪切速率依赖性的动态演变，并确定了剪切应力和剪切变形状态的三个阶段。试验结果表明，剪切刚度和岩石不连续性的动态变化与裂纹扩展的剪切速率相关行为有关，随着法向应力和/或节理粗糙度系数的增加而增加。剪切刚度降低的阶段对应于剪切速率依赖性显着的阶段，并且发现剪切速率对初始裂纹应力没有影响。