Characterization of 3D Displacement and Stress Fields in Coal Based on CT Scans
Abstract
:1. Introduction
2. Materials and Methods
2.1. Sample Preparation
2.2. Experimental Device and Methods
2.3. Boundary Delineation of 3D CT Model
2.4. Displacement Field Algorithm and ROI Delineation
3. Results
3.1. Deformation and Failure Features
3.2. Results for 3D Displacement Field
3.3. Analysis of Simulation Results
4. Conclusions
- Primary fractures and minerals have a determining influence on the deformation and failure features of coal and are the key factors producing anisotropic coal deformation. The primary fractures propagate as compression increases and crisscross new fractures.
- The ROI displacement field data of different matrices in the coal sample follow a normal distribution, and the differences in the corresponding deformations under load are statistically significant. The deformation at the primary fractures increases substantially with stress, and the mineral region is also prone to large deformation from stress concentration. The increase in the displacement is promoted by the presence of fractures and inhibited in the presence of minerals.
- A highly complex coal stress state forms under an applied stress, and the distribution of minerals and fractures significantly affects the stress field distribution. The presence of minerals and fractures produces a prevalent shear stress in the coal that is mainly concentrated in the vicinity of where these entities are located and is highly unfavourable for sample stability.
- To ensure safe field operation, the mineral distribution features in coal seams and the development level and distribution features of primary fractures should be determined. Targeted measures can then be taken to improve the stress state and enhance the safety level.
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Conflicts of Interest
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Item | Stage | ROI1 | ROI2 | ROI3 |
---|---|---|---|---|
Mean displacement | All stages (μm) | 76.887 | 73.613 | 66.089 |
Post-peak stage (μm) | 148.336 | 136.263 | 117.470 |
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Li, Q.; Li, Z.; Li, P.; Pan, R.; Zhang, Q. Characterization of 3D Displacement and Stress Fields in Coal Based on CT Scans. Mathematics 2022, 10, 2512. https://doi.org/10.3390/math10142512
Li Q, Li Z, Li P, Pan R, Zhang Q. Characterization of 3D Displacement and Stress Fields in Coal Based on CT Scans. Mathematics. 2022; 10(14):2512. https://doi.org/10.3390/math10142512
Chicago/Turabian StyleLi, Qi, Zhen Li, Peng Li, Ruikai Pan, and Qingqing Zhang. 2022. "Characterization of 3D Displacement and Stress Fields in Coal Based on CT Scans" Mathematics 10, no. 14: 2512. https://doi.org/10.3390/math10142512
APA StyleLi, Q., Li, Z., Li, P., Pan, R., & Zhang, Q. (2022). Characterization of 3D Displacement and Stress Fields in Coal Based on CT Scans. Mathematics, 10(14), 2512. https://doi.org/10.3390/math10142512