A Split-Hopkinson pressure bar was used to carry out a series of impact tests on prefabricated granite specimens containing joints with different inclination angles and at different joint persistency values. The results were used to determine the degradation effect of the non-persistent joints on the specimens and investigate the failure mechanism of the granite subjected to impact load. The effect of varying the length and inclination angle of the joint on the dynamic characteristics of the granite was systematically analyzed based on a consideration of the specimens’ dynamic mechanical properties. A continuum-discrete coupled model was subsequently established based on the results of the laboratory tests and used to investigate the failure mechanism and crack propagation behavior occurring on a microscopic scale. The results show that the geometric parameters of the joints and the loading rate have a significant effect on the dynamic response of the granite. Moreover, there is a good power function relationship between the dynamic increase factor and loading rate of the prefabricated jointed rock specimen when the loading rate is low to medium. As the inclination angle of the joint increases, the failure mode of the specimen transitions from tensile splitting failure → mixed tensile–shear failure → main shear failure → micro-damage failure. As the penetration of the joint increases, the failure mode of the specimen evolves from micro-damage failure → tensile splitting failure → mixed tensile–shear failure. When subjected to uniaxial impact loading, the main cracks in the jointed rock specimen are usually wing cracks and coplanar cracks. Anti-wing cracks are not generated by themselves but appear alongside other cracks as a supplementary means of achieving stress release. The present results offer a sound basis for evaluating the stability of jointed rock mass under the dynamical loading.

采用Split-Hopkinson压力棒对包含不同倾角节理和不同节理持久性值的预制花岗岩试件进行一系列冲击试验。结果用于确定非持久节理对试样的退化影响，并研究花岗岩在冲击载荷作用下的破坏机制。在考虑试件动态力学特性的基础上，系统分析了节理长度和倾角的变化对花岗岩动力特性的影响。随后根据实验室测试的结果建立了连续离散耦合模型，并用于研究失效机制和裂纹扩展在微观尺度上发生的行为。结果表明，节理几何参数和加载速率对花岗岩动力响应有显着影响。此外，预制构件的动态增加系数与加载率之间存在良好的幂函数关系。当加载速率从低到中等时，节理岩石样本。随着节点倾角的增大，试件的破坏模式由拉劈破坏→拉剪混合破坏→主剪破坏→微损伤破坏转变。随着接头贯入度的增加，试件的破坏模式由微损伤破坏→拉伸劈裂破坏→拉剪混合破坏演变。单轴冲击载荷作用下，节理岩石试件的主要裂纹通常为翼状裂纹和共面裂纹。反翼裂纹不是自己产生的，而是与其他裂纹一起出现，作为实现应力释放的辅助手段。目前的结果为评估节理岩体在动力加载下的稳定性提供了良好的基础。