Experimental Investigation on the Energy Storage Characteristics of Red Sandstone in Triaxial Compression Tests with Constant Confining Pressure

Abstract

The elastic energy stored in deep rock in three-dimensional stress environment is the energy source of rockburst. To investigate the energy storage characteristics of deep rock under different confining pressures, a series of triaxial single-cyclic loading-unloading compression tests were conducted on red sandstone specimens under eight confining pressures. The input energy density, elastic energy density, and dissipative energy density of the specimen in axial, circumferential, and total directions can be obtained by the area diagram integration method. The results show that the input energy density in the axial direction accounts for the largest logarithmic proportion of the total input energy density, and the relationship between all energy density parameters and unloading level can be described by quadratic function. In the axial direction, there is a linear function relationship among elastic energy density, dissipative energy density, and input energy density. In the circumferential direction, there is a quadratic function relationship among elastic energy density, dissipative energy density, and input energy density. For the total energy density parameters of the rock specimen, the relationship among elastic energy density, dissipative energy density, and input energy density conforms to the quadratic function. According to the above correlation function, the elastic energy stored in deep rock under different confining pressures can be accurately obtained, which provides a foundation for studying the mechanism of rockburst under three-dimensional unloading from the energy perspective.

A Review of Mechanical Properties and Rockburst Investigation of Transversely Isotropic Rocks by Experimental Technique

“…It has been reported that a certain miscalculation often happens during rockburst proneness discrimination using these indexes [142]. Recently, Gong et al [143][144][145] first discovered the linear energy storage law, which was proved to be applicable to many materials such as rock, coal [146], and concrete [147] and various test types (the uniaxial compression test [148][149][150][151][152], triaxial compression test [153,154], tension test [144], shear test [155], and three-point flexural loading test [156]). They also established a new rockburst proneness criterion based on the residual elastic energy index, and the accuracy of rockburst discrimination was greatly improved.…”

Experimental Study of Strain Rockburst considering Temperature Effect: Status‐of‐the‐Art and Prospect

“…With further exploration, it is found that the rocks possess the linear energy storage law in three-dimensional compression [59], preset angle shear test [60], and fracture test [61], as well as the pre-heated granite specimens in the UC test [46]. erefore, when investigating the failure of deep high-temperature rock, adopting the linear energy storage law can accurately calculate extremity energy storage as well as residual elastic strain energy during the whole process, to realize the quantitative evaluation of rockburst proneness.…”

Effect of Joint Density on Rockburst Proneness of the Elastic‐Brittle‐Plastic Rock Mass

“…Before the failure of the rock mass, a large amount of elastic strain energy will accumulate in the stress concentration area. When the elastic strain energy is released suddenly in the free face, the rock will produce violent brittle failure in a short time, causing serious dynamic disasters [13][14][15]. Rock mass with rockburst proneness is usually elastic-perfectly brittle rock mass with few cracks or only hidden cracks [4,16,17].…”