The shear strength of rock joints under dynamic normal load (DNL) conditions is quite different from that under constant normal loading (CNL) conditions. However, existing studies seldom involve the shear strength prediction of rock joints under DNL conditions. Therefore, a series of shear tests for rock joints under DNL conditions were carried out. The evolutions of the shear strength parameters, including both cohesion and internal friction angle, with dynamic loading amplitude and frequency were investigated according to the experimental results. A shear strength criterion for rock joints under DNL conditions was developed. The proposed model was verified by comparing the theoretically predicted values with experimental results, both of which showed excellent agreement. Additionally, the strength criterion is utilized to predict the peak shear strength under CNL and new DNL conditions. These prediction results were further validated by experimental methods, which extend the applicability of the proposed strength criterion. This study can provide valuable references for the stability evaluation of rock formation engineering and geological hazard warning under dynamic load disturbance.

中文翻译：

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动法向载荷作用下岩石节理的抗剪强度判据


动法向载荷 （DNL） 条件下岩石节理的抗剪强度与恒定法向载荷 （CNL） 条件下的岩石节理抗剪强度差异较大。然而，现有研究很少涉及 DNL 条件下岩石节理的抗剪强度预测。因此，在 DNL 条件下对岩石节理进行了一系列剪切试验。根据试验结果，研究了抗剪强度参数（包括内聚力和内摩擦角）随动载荷幅值和频率的变化。开发了 DNL 条件下岩石节理的抗剪强度准则。通过将理论预测值与实验结果进行比较来验证所提出的模型，两者显示出极好的一致性。此外，强度准则用于预测 CNL 和新 DNL 条件下的峰值剪切强度。这些预测结果通过实验方法进一步验证，扩展了所提出的强度准则的适用性。该研究可为动载荷扰动下岩层工程的稳定性评价和地质灾害预警提供有价值的参考。