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Updated: Jul 12, 2025
10:27
A Uniaxial Compression Experiment with CO2-Bearing Coal Using a Visualized and Constant-Volume Gas-Solid Coupling Test System
Published on: June 12, 2019
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Investigation of crack recognition and spatio-temporal evolution pattern in coal samples damage
Zeng Chen1,2, Ping Wang3,4, Feng Shi3,4
1BGRIMM Technology Group, Building 23, Zone 18 of ABP, No. 188, South 4th Ring Road West, Beijing, 100160, People's Republic of China. zschenzeng@126.com.
Scientific Reports
|October 20, 2023
Summary
Understanding coal crack evolution is key to rock mass stability. Acoustic emission experiments reveal microcrack patterns and predict instability using spatio-temporal entropy and fractal dimension.
Area of Science:
- Rock Mechanics
- Geophysics
- Materials Science
Background:
- Crack evolution in rock masses is crucial for understanding mass behavior and instability.
- Acoustic emission (AE) techniques offer insights into crack propagation mechanisms.
Purpose of the Study:
- To investigate the spatio-temporal evolution of microcracks in coal under uniaxial compression.
- To analyze the relationship between crack distribution patterns, spatio-temporal entropy (H), and fractal dimension (D).
- To identify precursor information for coal sample instability.
Main Methods:
- Uniaxial compression tests on coal samples.
- Simultaneous acoustic emission positioning and monitoring.
- Application of clustering theory to analyze microcrack distribution.
- Calculation and analysis of spatio-temporal entropy (H) and fractal dimension (D).
- Machine learning for crack identification.
Main Results:
- Microcracks exhibit a statistical equilibrium distribution, fitting a Gaussian model.
- Fractal dimension (D) correlates with the spatial characteristics of 3D elliptical cracks.
- Low-dimensional cluster cracks are prone to developing into macroscopic cracks.
- Changes in spatio-temporal entropy (H) are linked to crack formation processes.
Conclusions:
- Abnormal changes in spatio-temporal entropy (H) can serve as precursors to coal sample instability.
- The study presents a novel method for analyzing crack distribution and formation.
- The proposed method demonstrates effectiveness in assessing coal damage states.
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