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A Methodology for Fault Pre-Consolidation prior to Longwall Retreat: A Case Study from Kestrel Coal
By Dion Pastars
Kestrel Coal has undertaken a surface-to-seam consolidation program of faulted ground prior to longwall retreat in the 304 panel. Micro fine cement is used to improve the rock mass quality and the
Jan 1, 2007
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Influence Of Support Capacity And Geometry On Tailgate Support
By E. Hosca
Alternative tailgate loading conditions due to conventional and conventional/yield pillar combinations were evaluated to define roof loading. In order to isolate different loading situations, the tail
Jan 1, 1994
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Mine Convergence When Using Mobile Roof Supports In Pillar Recovery
By J. R. Stoltz
To date, there has been limited formal research dealing with the use of Mobile Roof Supports (MRS) for pillar recovery. This paper, which is a portion of a larger project, presents convergence data fr
Jan 1, 1999
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A Decade of Mobile Roof Support Application in the United States
By Larry Howe
Second, or retreat mhng with Mobile Roof Supports (MRS) has now been part of coal mining in the United States for a decade Their utilization has evolved into mining applications which vary in seam hei
Jan 1, 1998
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Roof Screening: Best Practices and Roof Bolting Machines (e5909744-6953-4a41-b02f-21226966b63f)
By Susan Robertson
Many injuries are caused each year by rock falls in coal mines. Most of these injuries are not caused by major roof collapses, but from falls of smaller rocks from the immediate top or roof skin. Vari
Jan 1, 2002
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Investigation Of Pillar-Roof Contact Failure In Northern Appalachian Stone Mine Workings (55897abb-5ce0-4661-bf26-04d03fe5d67b)
By Gabriel Esterhuizen
The roof rock in underground limestone mines in Northern Appalachia can be subject to high horizontal stresses in spite of the shallow depth of the workings. The high stresses can cause roof stability
Jan 1, 2004
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Evaluation Of Existing Predictive Methods For Mine Subsidence In The U. S. (1ec2d374-5864-4775-9b19-24759c4f95be)
By Vladimir Adamek
Two existing predictive methods were chosen for evaluation; an influence function (Gals Theory) and a profile function (hyperbolic). These were applied to several field measured subsidence pro¬files o
Jan 1, 1981
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Utilization Of Polymer Grid Structures In Shield Recovery Operations
By Brian E. Travis
Recent Developments in the utilization of polymer grid structures for Longwall Shield Recovery operations are discussed. Specifically: various Longwall screen designs and the numerous methods employed
Jan 1, 1993
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Numerical Modeling the Interburden Impact on Multiple-Seam Coal Mining in Western China
By Jimin Su, Enguang Zhu, Kangning Zhang, Yang Li
"The effect of interburden on overlying strata movement during the mining of a lower group coal seam is still a challenge in China. Based on the multiple coal seams in western China, numerical simulat
Jan 1, 2017
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Rock Reinforcement Longevity
By Francis S. Kendorski
Rock reinforcement has been in widespread use and generally has been accepted in underground mining and tunneling since the 1950s. The first rock reinforcement technologies employed were mechanical an
Jan 1, 2000
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Investigation of Electromagnetic Emissions in a Deep Underground Mine (0366ea57-3ba7-4a00-bec7-825a048e7e26)
By Douglas Scott
Highly stressed rock in stopes continues to be a primary safety risk for miners in underground mines because it can result in failures of ground that lead to both injuries and death. Spokane Research
Jan 1, 2004
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Application Of DDM To Some Rock Pressure Problems In Japanese Deep Coal Mines
By Yoshiaki Fujii
Displacement Discontinuity Method (DDM), which was originally developed by Crouch,S.L., is a powerful tool to calculate mechanical disturbances due to tabular excavations. Three topics on DDM applicat
Jan 1, 1992
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Load Deformation Behavior Of Simulated Longwall Gob Material
By Deno M. Pappas
The purpose of this U.S. Bureau of Mines study was to determine the material stiffness properties of the gob for use in numerical models of rock mass response to longwall mining. Photographs of actual
Jan 1, 1993
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Field Measurements of Chain Pillar Response to Longwall Abutment Loads
By Christopher Mark
Current longwall pillar design methods are based on many assumptions about pillar and entry response to longwall abutment loads. Knowledge of the magnitude and time-of-arrival of abutment loads is ess
Jan 1, 1986
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The Impact Factors of Overburden Movement in Longwall Mining of Shallow Coal Seams
By Yang Li
For the study of overburden movement in longwall mining of shallow coal seams, most scholars merely consider the thickness of bedrock and top soils. In this paper, the overburden movement in longwall
Jan 1, 2014
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Safe Pillar Extraction Practice - Some Geotechnical Principles Based on Australian Experience
By Bruce K. Hebblewhite
Underground pillar extraction continues to be practiced in Australia in various forms, in spite of the dominance of the longwall method, which accounts for over 90% of underground production. Australi
Jan 1, 2011
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Rigid Or Yielding Roof Bolts: At The Face Or Away From The Face (3eff2ffb-d0b3-4171-9439-10f9fdec54f7)
By R. D. Lama
The concept of rigid or yielding bolts is discussed based upon support requirements for excavations of equivalent geomechanical behaviour. The concept of equivalent geomechanical behaviour is introduc
Jan 1, 1992
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The Influence Of Stream Valleys On Coal Mine Ground Control
By John L. Hill
Over 50 mines of the Appalachian and Illinois Basins are presently experiencing poor ground conditions believed to be caused by overlying stream valleys. The Bureau of Mines is conducting research int
Jan 1, 1988
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Laboratory and In Situ Results of a Slip Nut Yielding Rock Bolt System
By John D. VandeKraats
Yielding rock bolt systems have been developed to provide ground support while accommodating shifting, creeping, or swelling ground movements. The Dywidag Systems, Inc. (DSI) Slip Nut System is one su
Jan 1, 1998
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Mitigation of a Massive Sandstone Channel's Impact on a 1,500 Ft Wide Longwall Face
By Daniel W. Su
This paper presents the implementation and evaluation of the hydraulic fracturing technique and Longwall Visual Analysis (LVA) software to mitigate the impact of a 1,000-ft (305-meter) widemassive san
Jan 1, 2012