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Updated: Jun 14, 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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Experimental study on dynamic mechanical properties of multidirectional constrained water-bearing coal samples under
Beijing Xie1, Ben Zhang2, Shunkun Zhao3
1School of Emergency Management and Safety Engineering, China University of Mining and Technology, Beijing, 100083, China.
Scientific Reports
|September 4, 2024
Summary
Deep water affects coal's mechanical properties. Saturated coal shows lower strength at low strain rates but higher strength at high rates due to water's influence.
Area of Science:
- Geotechnical Engineering
- Rock Mechanics
- Materials Science
Background:
- Understanding coal and rock behavior under deep water is crucial for safe mining and underground construction.
- Dynamic mechanical properties are key to predicting failure under impact loading.
Purpose of the Study:
- To investigate the dynamic mechanical properties of coal under deep water conditions.
- To analyze the influence of water content on coal's strength, energy dissipation, and fractal dimension.
Main Methods:
- Utilized an enhanced Split Hopkinson Pressure Bar (SHPB) testing system for dynamic impact experiments.
- Conducted five sets of experiments on coal samples with varying water content and loading conditions.
- Employed the HJC model and ANSYS/LS-DYNA for numerical simulations of coal failure.
Main Results:
- Saturated coal exhibited lower dynamic strength at low strain rates but higher peak strength at high strain rates compared to natural coal.
- Energy absorption of saturated coal was 10-30% lower, with deformation hysteresis observed in natural coal.
- Fractal dimension and fine particle content increased in saturated coal under combined loading.
Conclusions:
- Water content significantly alters the dynamic mechanical properties and failure mechanisms of coal.
- Numerical simulations closely corroborated experimental findings, validating the HJC model for predicting coal failure.
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