Please use this identifier to cite or link to this item:
http://bura.brunel.ac.uk/handle/2438/29353
Title: | Crack and failure behaviors of sandstone subjected to dynamic loads visualized by micro-computed tomography |
Authors: | Zhang, X Guo, P Gao, X Zou, C Wang, K Hu, J Sun, Y Lei, L |
Keywords: | dynamic rock failure;3D observation;microscopic failure mechanism |
Issue Date: | 15-May-2024 |
Publisher: | Elsevier on behalf of Institute of Rock and Soil Mechanics, Chinese Academy of Sciences |
Citation: | Zhang, X. et al. (2024) 'Crack and failure behaviors of sandstone subjected to dynamic loads visualized by micro-computed tomography', Journal of Rock Mechanics and Geotechnical Engineering, 0 (in press, corrected proof), pp. 1 - 15. doi: 10.1016/j.jrmge.2024.05.001. |
Abstract: | Microscopic dynamic failure behaviors of rocks are significant to rock engineering, which is still insufficiently understood. This study combines split Hopkinson pressure bar (SHPB) and micro-CT (computed tomography) to explore the microscopic failure characteristics of sandstone under impact loading. SHPB is responsible for the dynamic test, and micro-CT is responsible for pre- and post-test inspections. The results show that the pores and defect influence the dynamic strength but do not alter the overall trend of increased strength with a higher impact level. The dynamical crack development is then analyzed. Three types of cracks (i.e. I-, Y-, and H-type) are identified to describe the crack development. When rock is simply fractured, only I-type crack exists due to tensile failure, and it grows irregularly. As the strain rate increases, I-type crack is transformed into Y- and H-type crack due to shear failure. Crack coalesces at that moment, and the complexity increases along the impact direction. The coalescence occurs preferentially in the area with more pores, and around a third of pores are involved, where the maximum contribution area is in the middle of sample. Microcracks are formed inside the rock blocks, and rock grains and fragments fill in the cracks. The dynamic crack development is accompanied by microcracks, while rock grains and fragments result from the development of these microcracks. In addition, the influence of a semi-penetrating defect perpendicular to the impact direction is investigated. The defect can impede stress transfer and concentrate energy consumption. The findings are expected to enhance understanding of rock dynamics and support rock engineering development. |
URI: | https://bura.brunel.ac.uk/handle/2438/29353 |
DOI: | https://doi.org/10.1016/j.jrmge.2024.05.001 |
ISSN: | 1674-7755 |
Other Identifiers: | ORCiD: Xingyu Zhang https://orcid.org/0000-0003-4217-0991 ORCiD: Xiangbo Gao https://orcid.org/0000-0001-7123-2675 ORCiD: Chunjiang Zou https://orcid.org/0000-0001-9646-0236 ORCiD: Liang Lei https://orcid.org/0000-0002-5276-3822 |
Appears in Collections: | Dept of Civil and Environmental Engineering Research Papers |
Files in This Item:
File | Description | Size | Format | |
---|---|---|---|---|
FullText.pdf | Copyright © 2024 Institute of Rock and Soil Mechanics, Chinese Academy of Sciences. Production and hosting by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/ licenses/by-nc-nd/4.0/). | 5.13 MB | Adobe PDF | View/Open |
This item is licensed under a Creative Commons License