Li Hao, Pel Leo, You Zhenjiang, Smeulders David
Department of Mechanical Engineering, Eindhoven University of Technology, 5600 MB, Eindhoven, The Netherlands.
Department of Applied Physics, Eindhoven University of Technology, 5600 MB, Eindhoven, The Netherlands.
Sci Rep. 2024 Jul 29;14(1):17454. doi: 10.1038/s41598-024-68114-2.
Rock strength is imperative for the design and stability analysis of engineering structures. The Mohr-Coulomb (M-C) criterion holds significant prominence in geotechnical engineering. However, the M-C criterion fails to accurately capture the nonlinear strength response and neglects the critical state of rocks, potentially leading to inaccuracies in the design phase of deep engineering projects. This study introduces an innovative stress-dependent friction angle and cohesion (SFC) for the M-C criterion to capture the nonlinear strength responses of intact rocks, spanning from non-critical to critical states (brittle to ductile regions). A novel method for determining these stress-dependent parameters at each corresponding is initially introduced. Subsequently, an examination of the confinement dependency of the friction angle and cohesion is conducted, leading to the derivation of the SFC model. The SFC-enhanced M-C criterion, utilizing parameters obtained from triaxial tests under lower , demonstrates the capability to delineate the complete non-linear strength envelope from brittle to ductile regions. Validation through triaxial test data confirms that the predictions of the SFC-enhanced M-C criterion accurately correspond to the strength characteristics of the tested rocks.
岩石强度对于工程结构的设计和稳定性分析至关重要。摩尔-库仑（M-C）准则在岩土工程中具有显著的重要性。然而，M-C准则未能准确捕捉非线性强度响应，并且忽略了岩石的临界状态，这可能导致深部工程项目设计阶段出现不准确的情况。本研究为M-C准则引入了一种创新的应力相关摩擦角和黏聚力（SFC），以捕捉完整岩石从非临界到临界状态（从脆性到延性区域）的非线性强度响应。最初介绍了一种在每个相应状态下确定这些应力相关参数的新方法。随后，对摩擦角和黏聚力的围压依赖性进行了研究，从而推导出SFC模型。利用在较低围压下通过三轴试验获得的参数的SFC增强型M-C准则，展示了描绘从脆性到延性区域完整非线性强度包络线的能力。通过三轴试验数据进行的验证证实，SFC增强型M-C准则的预测与测试岩石的强度特性准确对应。
