Study on mechanical behavior and failure mechanism of specimens with single joint subjected to dynamic cyclical loading

Abstract

Jointed rock masses are a common phenomenon in rock engineering and are vulnerable to cyclic loads caused by earthquakes, blasts, and traffic loads.Therefore, it is crucial to comprehend the fatigue characteristics of jointed rock masses under dynamic cyclic disturbance for long-term stability assessments of rock engineering structures. This paper aims to investigate the effects of distinct joint inclinations under pre-cyclic loading on the strength and failure characteristics of rock-like specimens using experiments and numerical simulations. The results indicate that cyclic loading decreases the strength of the specimen, and the strength characteristics of the specimen are more apparent as the joint inclination angle becomes smaller. Furthermore, insights into different upper limit stress fatigue behaviors were gained by analyzing strength characteristics, crack propagation characteristics, and failure modes. Numerical results show that the damage degree of cyclic loading at high-stress levels is linked to the joint inclination angle and carrying capacity of specimens, and high cycle stress levels have an impact on the failure mode of the specimen.cyclic load, damage and failure, jointed rock, numerical modeling, particle flow Highlights 1. The damage degree of jointed specimens at different upper limit stress cyclic levels was investigated.2. The sensitivity of jointed specimens to cyclic stress-level damage was revealed.3. The macro and meso fatigue behaviors of jointed specimens were discussed.

Biomechanical evaluation of a fixation technique with a modified hemicerclage for tibial tuberosity transposition: an ex vivo cadaveric study

“…The occurrence of bone fractures at lower forces in the raccoon dog study may be attributed to several factors. These include inherent species-based differences in bone quality, variations in the age of the specimens, and the methodologies used for specimen storage and preparation, particularly freeze/thaw processes ( 29 , 32 , 33 ). Such factors can significantly impact the biomechanical properties of the bones, thereby influencing the outcomes of biomechanical testing.…”

A Numerical Method for Evaluating the Collapse of High-Steep Scarp Slopes Based on the Bonded Block Model–Discrete Fracture Network Model

“…Zhang et al [29][30][31][32][33][34] conducted research on the failure criteria of rocks. Chen et al [35][36][37][38] conducted research on the failure criteria of jointed rocks. However, they did not systematically analyze the collapse of high-steep scarp slopes, so either the chosen parameters were inadequate or the analytical process was inapplicable to judging the stability of steep scarps, thus failing to guide engineering design and safe construction.…”