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A Cooperative Study Of Gate Entry Designs Welbeck Colliery (UK) And Jim Walter Resources (USA)
By Greg Hendon
Longwall developments in the UK have historically consisted of single entry gate roads. Adjacent developments were separated from existing panels by large barrier pillars (designed of sufficient width
Jan 1, 1995
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Determining Horizontal Stress Direction Using The Stress Mapping Technique
By T. P. Mucho
Mine roof failure due to excessive horizontal stress has been recognized as a major cause of hazardous roof conditions in some mines. Stress measurements gathered by the U.S. Bureau of Mines (USBM) at
Jan 1, 1994
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Pillar Design In Bump-Prone Deep Western U.S. Coal Mines (e849bf38-924c-4a19-8729-5910f69616a3)
By N. P. Kripakov
This paper presents a brief overview of current bump mechanics theories and pillar design methodologies, and relates these concepts to experiences at two mines located in a north-central Utah coalfiel
Jan 1, 1992
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Longwall Recovery Utilizing The Open Entry Method And Various Cement-Concrete Supports
By E. Bauer
During 1987 and 1988, the Eighty Four Complex Mine of BethEnergy Mines, Inc. used the open entry longwall recovery method to recover one partial and three complete longwall faces. Various cement- conc
Jan 1, 1988
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Shield Monitoring To Forecast Severe Face Weightings At The South Bulga Colliery, NSW, Australia
By Jim Sandford
The South Bulga Colliery longwall operation, owned and operated by Cyprus Coal Australia. Oakbridge Pty. Ltd., and located near Singleton, NSW, is currently operating under an average 80-ft-thick (24-
Jan 1, 1999
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Modern Geotechnical Exploration And Mine Design
By Patrick S. Artrip
A deep mining operation in the Lower Kelly (Imboden) seam in Wise County, Virginia experienced severe ground control conditions in its attempt to develop reserves situated under increasingly higher co
Jan 1, 1993
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Design And Planning Of Lower Seam Longwall Gateroads
Case study data were analyzed to develop and quantify empirical stress transfer relationships between seams for both longwall and room and pillar mines. Layering in the innerburden and the distance be
Jan 1, 1995
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Effects of Panel Mining Sequence and Retreat Direction on the Roof Stability of Longwall Headgate Entries
By Jinsheng Chen
The major functions of longwall headgate entries are to provide access ways to the outby submains or mains for coal transportation and to the longwall face for fresh air and for transporting men and m
Jan 1, 1998
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Innovative Rock Reinforcement Hardware (a5497235-47bd-4c2e-8654-b4e79927169e)
By D. F. Howarth
Two innovative ground reinforcement products have been developed for use in the mining industry. One of these products is a high strength polyethylene (HOPE) bar for use as a rib bolt in underground c
Jan 1, 1992
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A probabilistic approach to ground support design in underground mines,
By Kevin Beauchamp
In many cases traditional support designs cover the many variations in ground conditions and bolt performance by a conservative factor of safety. The result is that most bolts are ineffectual most of
Jan 1, 2003
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The Use of NDT Methods to Determine the Condition of Rockbolt Support During the Recovery of a Previously Flooded Coal Mine Roadway at Thoresby Colliery
By Brian Clifford
Thoresby Colliery is in the process of recovering an old roadway that was flooded following the closure of an adjacent mine. The aim is to re-use the roadway as a gate road for a longwall retreat pane
Jan 1, 2002
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Vertical Stress Redistribution Around A Retreating Longwall Face End
By D. A. Payne
Large excavations, such as Iongwall panels, result in extensive vertical stress redistribution in the surrounding strata. The large abutment stresses developed may produce damage to pre-existing or pl
Jan 1, 1995
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Ground Control And Safety Considerations During Longwall Recovery
By William J. Gray
The Roof Control Division of MSHA's Pittsburgh Safety and Health Technology Center has been conducting a program to evaluate methods employed by the U.S. coal mining industry during recovery of l
Jan 1, 1993
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Investigation into the Extent and Mechanisms of Gloving and Un-mixed Resin in Fully Encapsulated Roof Bolts
Effective strata control, utilising fully encapsulated roof bolts, is dependent on the installed quality of the reinforcement elements. One mechanism by which fully encapsulated roof bolts may become
Jan 1, 2003
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The Application Of Rock Mass Classification Principles To Coal Mine Design In UK Conditions
By David J. Reddish
Longwall systems are inflexible in layout, intolerant of disruption and represent a substantial investment. It is therefore essential drat all understanding of the likely strata behaviour and support
Jan 1, 2000
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Integrating Ground Control And Mine Site Data Through A Geographic Information System
By Douglas C. Peters
Part of the ground control research at the U.S. Bureau of Mines is involved with improving ground control data collection and analysis methods. A geographic information system (GIs) is being used with
Jan 1, 1990
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Rock Bursting and Seismicity During Ramp Development, Lucky Friday Mine, Mullan, Idaho (70e1cb23-d3f9-44e0-89bb-620862946d41)
By J. K. Whyatt
A comprehensive survey of mine seismicity and rock bursting during development of two sublevels at the Lucky Friday Mine, Mullan, ID, USA, was conducted to better define rock failure mechanisms and so
Jan 1, 1998
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Evaluation of Pillar Recovery in Southern West Virginia (0e64fb3d-0c07-4638-b455-a16004535ca1)
By Chris Mark
Pillar recovery continues to be a significant ground control hazard. During the past decade, 10 miners were killed during pillar extraction operations in southern West Virginia. Studies conducted duri
Jan 1, 2002
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Hydraulic Prestressing Units: An Innovation In Roof Support Technology (6dbf7428-5679-47b2-a60c-95193c59dbda)
By Thomas Barczak
A new generation of hydraulic mine support prestressing devices has been developed. These thin-walled steel shells are machine-welded and can be inflated with water or any liquid to provide prestressi
Jan 1, 2004
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Statistical Characterization Of Coal-Mine Roof Failure: Suggestions And Case Study
By Alan D. Smith
[A standardized checklist in a questionnaire format, was established to investigate selected factors associated with coal nips roof falls, as derived from an intensive review of the literature. A plot
Jan 1, 1984