Influence of dynamic disturbed frequency on rock failure characteristics under triaxial cyclic and multistage unloading confining pressure loads

Abstract

This work aims to reveal the influence of disturbed frequency on the failure of deeply buried granodiorite under triaxial cyclic and multistage unloading confining pressure (CMSUCP) conditions. Testing results show that volumetric deformation is obviously influenced by the disturbed frequency. The volumetric strain was characterized as an early dilatancy-dominant behavior for a sample under low disturbed frequency. The deformation development at the unloading confining pressure stage is larger than at the cyclic loading stage. The hysteresis damping decreases with increasing disturbed frequency indicating that much energy loss occurs due to damage accumulation. A first slow followed by accelerated damage propagation is expressed using a radial irreversible strain-based damage evolution model. Macro-meso failure pattern analysis reveals that rock dominant failure changes from mixed tensile-shear failure to pure shear failure and a transmission from softening to hardening characteristics. It is suggested that failure develops fully for rock subjected to low disturbed frequency.

Acoustic emission characteristics and energy evolution law of rock damage process of different pore structures under cyclic loading

“…At present, the shallow mineral resources are decreasing or even depleting year by year, and the exploitation of metallic and non-metallic mineral resources is in the stage of comprehensive advancement to the deep part 1 . The mining 2 , 3 and blasting 4 , 5 processes in rock engineering, and the gas storage and production 6 processes in salt cavern engineering, are all subject to cyclic loads that deform the rock. Rocks are the basic components of engineering rock masses, and different engineering projects have different rock types.…”

The effect of cyclic stress amplitude on macro‐meso failure of rock under triaxial confining pressure unloading

“…Wang et al 22 conducted multistage confining pressure unloading and cyclic loading experiments for granodiorite samples, and the impact of the previous fatigue damage on rock macro‐meso failure characteristics was investigated. Afterward, they also conducted mechanical tests with similar loading paths, and the influence of loading frequency on rock failure characteristics and evolution was also revealed 23 . Although some efforts have been performed to reveal the mechanical properties and failure pattern by designing laboratory tests considering the unloading and fatigue loading, the disturbed amplitude of rock failure is not well understood.…”

“…Afterward, they also conducted mechanical tests with similar loading paths, and the influence of loading frequency on rock failure characteristics and evolution was also revealed. 23 Although some efforts have been performed to reveal the mechanical properties and failure pattern by designing laboratory tests considering the unloading and fatigue loading, the disturbed amplitude of rock failure is not well understood. However, the disturbed amplitude is very important in actual rock mass engineering; conventional fatigue tests have proved that cyclic stress amplitude impacts rock deformation, damage propagation, and the final failure modes.…”

Effect of Dry–Wet Cycling on the Degradation Characteristics and Mechanisms of Red Sandstone

“…Liu et al [12] and Wang et al [13] conducted creep tests on red sandstone samples subjected to different numbers of dry-wet cycles to study their long-term mechanical property changes. According to Wang et al [14,15], through a series of macro-meso fatigue failure analysis, the effect of block proportion on bimrocks under triaxial fatigue failure has been presented first. Huang et al [16] and Gan et al [17] investigated the deterioration characteristics of rocks resulting from acidic dry-wet cycles.…”