Related Experiment Video
Updated: Jul 8, 2026
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
Water-rich environments trigger coal instability risks via dynamic energy evolution and microscopic damage mechanisms
Hao Yang1, Yiju Tang2,3, Bing Jia1
1College of Municipal and Environmental Engineering, Henan University of Urban Construction, Pingdingshan, 467036, China.
Scientific Reports
|July 6, 2026
Summary
Water saturation significantly weakens coal, shifting failure modes from shear to tensile. This study reveals how water alters internal force chains and crack evolution, impacting coal mass stability.
Area of Science:
- Geotechnical Engineering
- Rock Mechanics
- Material Science
Background:
- Water-rock interaction critically affects coal mechanical properties and failure.
- Mechanisms of failure mode transition from dry to saturated coal are not fully understood.
Purpose of the Study:
- Investigate the mechanical response, crack evolution, and failure mechanisms of coal under dry and saturated conditions.
- Elucidate the mesoscale mechanisms governing failure mode transition due to water saturation.
Main Methods:
- Uniaxial compression tests on dry and water-saturated coal specimens.
- Particle flow numerical simulations to analyze crack evolution and force-chain networks.
- Quantitative characterization of mesoscale damage and internal stress redistribution.
Main Results:
- Water saturation reduces coal compressive strength and elastic modulus, accelerating damage.
- Dry coal exhibits conjugate shear failure; saturated coal shows tensile failure with increased fragmentation.
- Water weakens inter-particle bonds, disrupts force chains, and promotes tensile microcrack propagation.
Conclusions:
- Macroscopic coal failure is governed by the evolution and reorganization of internal force-chain networks.
- Water-induced weakening and force-chain disruption are key to tensile failure in saturated coal.
- Findings offer insights into water-bearing coal stability and disaster prevention.
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