Related Experiment Video
Updated: Oct 5, 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
8.8K
Similar experimental study on retaining waterproof coal pillar in composite strata mining
Y Q Wang1, X Wang2,3, J S Zhang1,4
1School of Civil Engineering, Central South University, Changsha, 410075, China.
Scientific Reports
|January 26, 2022
Summary
Mining coal seams near faults with confined water can cause water inrush. Physical models revealed stress, displacement, and water flow patterns, aiding in determining safe waterproof coal pillar widths.
Area of Science:
- Geotechnical Engineering
- Mining Engineering
- Hydrogeology
Background:
- Coal seam mining near faults under confined water presents risks of complex water inrush.
- Understanding water conduction, stress, and displacement is crucial for mine safety.
Purpose of the Study:
- To investigate water conduction, stress, and displacement during mining of coal seams under confined water near faults.
- To determine a safe width for waterproof coal pillars.
Main Methods:
- Physical similarity modeling using sand, lime, and plaster.
- Measurement of stress and displacement via mechanical sensors, total station, and video camera.
- Simulation of water conduction using a closed-loop system with pre-buried water bags in faults.
Main Results:
- Physical model test results were validated against elastoplastic limit equilibrium theory.
- The coal seam ahead of mining was divided into fault-affected, elastic, and plastic yield crack areas.
- A safe width for waterproof coal pillars was determined based on integrated analysis.
Conclusions:
- Physical models effectively simulate water inrush phenomena in coal seam mining near faults.
- The study provides a method to determine reasonable waterproof coal pillar widths.
- Findings contribute to safer mining practices in complex geological conditions.
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