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Updated: Jun 7, 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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Practical research on coal pillar retention in deep mining roadways
Lei Wang1, Gang Liu2, Pingyun Ma2
1School of Mining Engineering, Heilongjiang University of Science and Technology, Harbin, 150022, China. 15765589177@126.com.
Scientific Reports
|November 11, 2024
Summary
This study determined the optimal coal pillar size for deep retreat mining to be 7-8 meters, enhancing roadway stability and reducing safety hazards. Field tests confirmed an 8-meter pillar effectively managed stress and deformation.
Area of Science:
- Mining Engineering
- Rock Mechanics
- Geotechnical Engineering
Background:
- Traditional coal pillar design methods are insufficient for deep retreat mining.
- Deep mining presents challenges in roadway stability and safety.
- Optimizing coal pillar size is crucial for efficient and safe coal extraction.
Purpose of the Study:
- To determine the ultimate equilibrium size of coal pillars in deep retreat mining.
- To analyze stress transfer and surrounding rock plastic evolution under varying pillar sizes.
- To provide practical guidance for coal pillar design at the Pinggang Coal Mine and similar mining areas.
Main Methods:
- Mechanical experiments
- Theoretical calculations
- Numerical simulations
- Field tests
- Engineering application at Pinggang Coal Mine
Main Results:
- The ultimate equilibrium coal pillar size was determined to be 7.12-8.22 meters.
- Coal pillar sizes between 3-6 meters led to stress concentration and plastic failure.
- Pillars of 7-8 meters showed optimal stress distribution and roof control.
- Pillars of 9-10 meters offered no further improvement in bearing performance.
- An 8-meter pillar at Pinggang Coal Mine resulted in peak stress of 27.54 MPa and ideal deformations.
Conclusions:
- The optimal coal pillar size for deep retreat mining is 7-8 meters.
- This size range enhances roadway stability and minimizes coal loss.
- The findings offer theoretical and practical guidance for sustainable coal mining operations.
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