A New Apparatus for Testing Shear-Slip Properties of Rock Joint Subjected to Dynamic Disturbance

• Published in: Experimental mechanics 2024-06, Vol.64 (5), p.745-759
• Main Authors: Yuan, W., Li, J.C., Zou, C.J., Zhao, J.
• Format: Article
• Language: English
• Subjects: Biomedical Engineering and Bioengineering; Characterization and Evaluation of Materials; Control; Deformation; Destabilization; Dynamic stability; Dynamical Systems; Engineering; Initial stresses; Jointed rock; Lasers; Optical Devices; Optics; Photonics; Research Paper; Rock masses; Rock properties; Seismic stability; Seismic waves; Servocontrol; Shear stress; Shear tests; Slip; Solid Mechanics; Stress state; Test equipment; Vibration
• ISSN: 0014-4851; 1741-2765
• DOI: 10.1007/s11340-024-01060-2

Background To evaluate the stability of jointed rock masses subjected to dynamic disturbance, laboratory dynamic shear test on rock joint is necessary. Developing dynamic shear test equipment for rock joint is currently a pressing issue. Objective To address this issue, a new apparatus is developed to reproduce the shear-slip process of rock joint subjected to dynamic disturbance under various initial stress state. Methods The disturbance load, which has a dominant frequency close to that of seismic waves, is generated by an electromagnetic-driven disturbance generator, and its amplitude and duration can be accurately controlled in a stable manner. The initial normal and shear stresses can be applied in the shear test under dynamic disturbance using servo-controlled loading unit, which facilitates the simulation of the real stress state of rock joint. Results The shear tests under dynamic disturbance show that when an initial shear stress is applied to rock joint, an additional deformation stage of stress recovering can also trigger a slip displacement, which contributes to the destabilization of jointed rock masses. With increasing initial shear stress, the dynamic slip displacement, stress drop and post-disturbing deformation increase. The feasibility of the apparatus to conduct quasi-static direct shear tests with both the constant normal loading (CNL) and constant normal stiffness (CNS) boundaries is also verified. Conclusions Test results demonstrate that using the new apparatus, shear-slip properties of rock joint subjected to dynamic disturbance can be tested in various initial stress states.