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Chinese And North American High-Extraction Underground Coal Mining Strata Behavior And Water Protection Experience And Guidelines
By Mao Bai
Mining in situations where there exists a potential hazard from inundation has always existed in coal mining, and often reserves were left unmined in favor of reserves with no such hazard. However, in
Jan 1, 1995
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Drag Picks - Influence Of Tool Geometry And Angle Of Arrack On The Stress Evolution And Cutting Efficiency
During the last decade mechanical rock excavation has become increasingly widespread in the mining industry and, more in general, in excavation engineering. This technology, especially the tools and t
Jan 1, 1990
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Hydrogeologic Effects Of Subsidence At A Longwall Mine In The Pittsburgh Coal Seam
By Leslie Carver
The effects of longwall mine subsidence on water resources were studied at a West Virginia coal mine (mine Z) by Carver (1994). Data were obtained for 137 domestic supply wells and springs and 12 base
Jan 1, 1994
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Practical Aspects Of Longwall Pillar Design
By Christopher Mark
The past decade has provided a wealth of practical experience with longwall pillar design. Design formulas developed specifically for longwalls have proven their value in numerous applications. Analyt
Jan 1, 1990
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A New Method For Longwall Pillar Design
By P. Tsang
In order to deal with ground control problems such as roof falls, floor heaves and pillar failures in underground coal mines, a new pillar design method based on the "yield pillar" concept is proposed
Jan 1, 1993
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How to Design an Efficient Roof Bolting Plan Based on Simple In-Mine Measurements
By C. J. H. Brest van Kempen
The techniques developed should provide a useful tool, not only during the initial formulation of a suitable bolting plan for a new section, but also for periodic check¬ing on the utilization factor
Jan 1, 1986
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Assessment Of Applicability Of Strength Criteria For Rock And Rock Mass To Coal Pillars
The applicability of four empirical strength criteria for rock masses, namely, Hoek and Brown, Bieniawski - Yudhbir et al., Rarnamurthy - Arora and Johnston - Sheorey et al. has been tested against th
Jan 1, 1992
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Methods of Controlling Hard Roof in a Longwall Face
By Linsheng Xu
When coal seam is under the integral thick sandstone (or conglomerate), the structure of thick sandstone is integral and its strength is rather high. After coal is extracted, the roof is hanging and c
Jan 1, 1986
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Longwall Production, Maintenance, And Roof Control System
By W. Mark Hart
The current Automatic Data Acquisition system developed by some support manufacturers make it possible to monitor and record changes in leg pressure, DA RAM stroke in every shield and shearer position
Jan 1, 1994
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Subsidence Studies In Thick And Steep Coal Seam Mining
By M. Y. Fisekci
This paper concentrates on subsidence measurements, applied over the thick and steep seam mining in the Rocky Mountains Region of Western Canada. The studies to date indicate that two new subsidence m
Jan 1, 1981
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Reformation Of The Hydraulic Stowing Mining Method (81b9f573-b6ec-447f-bbcd-728c29bd41c4)
By Liang Yinhuai
The hydraulic-stowing mining method is most effective for mining thick coal seams. It is superior to the sliced cover-caving and artificial mining method and the fully mechanized sublevel-caving minin
Jan 1, 1992
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Automation Of A Progressive Failure Procedure For Analysis Of Underground Mine Pillar Designs
By N. P. Kripakov
The U.S. Bureau of Mines (USBM) is conducting research to develop a practical computer-based tool that will allow coal mine planners to anticipate rock mass behavior surrounding mine entries prior to
Jan 1, 1994
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In-Situ Investigation Into The Causes Of Falls Of Roof In South African Collieries
By J. Nielen van der Merwe
The main objective of the research described in the paper was to determine the causes of falls of roof in South African coal mines. The south African Colliery Manager's Association and the member
Jan 1, 2001
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Renewed Interest In Prop Supports As A Replacement For Wood Cribs
By Thomas M. Barczak
Wood cribs have been the dominant form of supplemental support in coal mining for many years. Recently, there has been a renewed interest in prop supports as a replacement for wood cribbing due to the
Jan 1, 1995
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Effect of High Horizontal Stress on Coal Mine Entry Intersection Stability
By K. Hanna
This manuscript describes an extensive ground control study at the Inland Steel No. 2 Mine near McLeansboro, IL, conducted by the U.S. Department of the Interior's Bureau of Mines (USEM) in coope
Jan 1, 1986
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Design Considerations For Bump-Prone Longwall Mines
Tailgate pillar and tailgate-face corner humps have been a major threat to longwall coal mines where hump-prone conditions exist. The yield pillar design concept, in which the longwall chain pillars a
Jan 1, 1999
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Comparison of Acoustic Emission and Stress Measurement Results to Evaluate the Application of the Kaiser Effect for Stress Determination in Underground Mines
By Lorraine Kent
Comparison of in-situ stress overcore measurement results with those determined from laboratory evaluation of Acoustic Emission (AE) testing on oriented sub-core samples has been carried out for a var
Jan 1, 2002
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Application Of A Static And Geophysical Monitoring System For Detection Of Stability Problems
By Maleki. Hamid
The U.S. Bureau of Mines implemented an inte¬grated static and geophysical monitoring program in a southern Wyoming mine to study changes in seismic wave propagation properties in roof strata. The pur
Jan 1, 1993
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Stability And Control Of Immediate Roof Of Fully Mechanized Coal Face
By S. Y. Liu
Based on the underground measurements, physical model test of simulated materials in the laboratory and finite element analysis, this paper demonstrates the pattern and process of roof fall over the t
Jan 1, 1990
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Geological Sensing - The Key To Increasing Miner Safety
By J. R. M. Hill
The U.S. Bureau of Mines is involved in research to improve geological sensing (or geo-sensing) techniques. This paper presents results from field trials of two research projects concerned with new te
Jan 1, 1992