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Showing 1 to 7 of 7 for “"retreat mining"”.
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Bump control design protocol for room-and-pillar retreat mining
… The protocol was developed for room-and-pillar retreat mining conducted with available continuous miner technology. The inability of existing coal pillar equations to accurately represent the wide total extraction pillars required, forced the development of the pseudoductile coal pillar strength …
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Ground control ramifications and economic impact of retreat mining on room and pillar coal mines
… mine. There are several variables such as depth, mining height, rock strength, mining geometry, roof and floor conditions, and retreat mining methods, which affect pillar extraction cost. Cost components of pillar extraction are classified as direct, indirect, fixed, and subsidence compensation …
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Preliminary Design of an Improved Load Measuring Device for Underground Mining Standing Supports
… is often used in conjunction with underground retreat mining. Knowledge of the load-displacement behavior of a standing support and loading induced by the mine opening is critical proper support selection. The NIOSH STOP database contains load-displacement laboratory test data for most commonly …
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Calibrating the LaModel Program for Shallow Cover Multiple-Seam Mines
… past decade, approximately 40% of underground mining fatalities were caused by roof falls, rib collapses, or bumps/bursts, 19% of which occurred during retreat mining (Pappas and Mark, 2012). In addition, approximately 600 miners are non-fatally injured (often severely) every year by rock falls …
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Microseismic Monitoring of a Room and Pillar Retreat Coal Mine in Southwest Virginia
… or rib (MSHA, 2015). Out of the underground coal mining methods, room and pillar retreat mining lacks significant research to adequately understand the rockmass behavior associated with the process. A microseismic monitoring system was installed in a retreat mine in Southwest Virginia to provide …
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Study of unstable rock failures using finite difference and discrete element methods, A
Case histories in mining have long described pillars or faces of rock failing violently with an accompanying rapid ejection of debris and broken material into the working areas of the mine. These unstable failures have resulted in large losses of life and collapses of entire mine panels. Modern …
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Investigation of coal bumps in the Pocahontas No. 3 seam, Buchanan County, Virginia
… the working places shortly after commencement of retreat mining in a given area. Since pillar mining offers the opportunity for achieving relatively high production at a low cost per ton the development of methods for the detection and distressing of areas of high bump probability in advance of …