Abstract
The joint arrangement in rock masses is the critical factor controlling the stability of rock structures in underground geotechnical engineering. In this study, the influence of the joint inclination angle on the mechanical behavior of jointed rock masses under uniaxial compression was investigated. Physical model laboratory experiments were conducted on jointed specimens with a single pre-existing flaw inclined at 0°, 30°, 45°, 60°, and 90° and on intact specimens. The acoustic emission (AE) signals were monitored during the loading process, which revealed that there is a correlation between the AE characteristics and the failure modes of the jointed specimens with different inclination angles. In addition, particle flow code (PFC) modeling was carried out to reproduce the phenomena observed in the physical experiments. According to the numerical results, the AE phenomenon was basically the same as that observed in the physical experiments. The response of the pre-existing joint mainly involved three stages: (I) the closing of the joint; (II) the strength mobilization of the joint; and (III) the reopening of the joint. Moreover, the response of the pre-existing joint was closely related to the joint’s inclination. As the joint inclination angle increased, the strength mobilization stage of the joint gradually shifted from the pre-peak stage of the stress–strain curve to the post-peak stage. In addition, the instantaneous drop in the average joint system aperture (aave) in the specimens with medium and high inclination angles corresponded to a rapid increase in the form of the pulse of the AE activity during the strength mobilization stage.
Highlights
IntroductionBased on the acoustic emission (AE) characteristics of the rock failure process, several researchers have conducted extensive laboratory research on the acoustic emissions (AEs) characteristics of rocks under compression [4,5,6], tension [7], shear [8], and fracture test conditions [9]
The acoustic emission (AE) event of a rock can be simulated by counting the number of bond breakages, and the results have shown that the maximum value of the AE lags behind the peak strength
Since a natural rock contains a large number of random cracks, it is difficult to quantitatively analyze the influence of the joint inclination angles on the mechanical behaviors laboratory
Summary
Based on the AE characteristics of the rock failure process, several researchers have conducted extensive laboratory research on the AE characteristics of rocks under compression [4,5,6], tension [7], shear [8], and fracture test conditions [9]. Mogi [10] conducted a large number of AE experiments on rocks and explored the AE characteristics of the rock fracture process under pressure. Since a natural rock contains a large number of random cracks, it is difficult to quantitatively analyze the influence of the joint inclination angles on the mechanical behaviors. Since a natural rock contains a large number of random cracks, it is difficult to quantitatively analyze the influence of the joint inclination angles on the mechanical behaviors laboratory. The geometry of the specimen and a photograph of a sample specimens were were 60 60 ×
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
