Critical Break Length of Floor Aquiclude During Longwall Mining Above Confined Aquifer
Volume 6, Issue 6, December 2017, Pages: 149-156
Received: Sep. 5, 2017;
Accepted: Sep. 21, 2017;
Published: Nov. 2, 2017
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Baohua Guo, Collaborative Innovation Center of Coal Work Safety, Jiaozuo, China; School of Energy Science and Engineering, Henan Polytechnic University, Jiaozuo, China; Key Laboratory of Safety and High-Efficiency Coal Mining, Ministry of Education (Anhui University of Science and Technology), Huainan, China
Feng Jiao, Collaborative Innovation Center of Coal Work Safety, Jiaozuo, China
Xiaoyu Yang, Shendong Coal Group Company, China Shenhua Energy Company Limited, Erdos, China
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Floor water inrushes not only cause heavy casualties and property losses, but seriously restrict the production of coal mines. The aquiclude was simplified as the fixed - fixed beam under the uniform load, and critical break length formula of floor aquiclude in three failure modes including bending failure, shear failure and buckling of pressure bar were established. Then the critical lengths of aquiclude in three failure modes were calculated according to the geological and mining conditions of 15031 panel in Jiulishan coalmine. The results show that the critical break length in bending failure is the smallest, while the critical length in shear failure mode is the biggest. And failures of fixed – fixed beam in three failure modes all occur at two ends so that water inrush from floor may occur at open-off cut or working face. Additionally, three critical break lengths increase with aquiclude thickness but decrease with confined aquifer pressure. According to the calculated results, water inrush may occur at the working face or open-off cut when mining advance reaches 12.47 m, and thus three control measures of lowering aquifer pressure, increasing aquiclude thickness and shortening the distances of first and interval weighting of main roof were discussed. The conclusions can provide references to control water inrush from floor aquifer in coal mines.
Coal Mine, Water Inrush, Floor Aquiclude, Fixed - fixed Beam, Critical Break Length
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Critical Break Length of Floor Aquiclude During Longwall Mining Above Confined Aquifer, Earth Sciences.
Vol. 6, No. 6,
2017, pp. 149-156.
Copyright © 2017 Authors retain the copyright of this article.
This article is an open access article distributed under the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/
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