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Use Of Database In Ground Control To Identify Weightings And Water Inflows
By G. C. Xiao
A database, incorporating historical data from British mines, to study the factors affecting inflows from proximate aquifers into longwall workings, showed that a main casual factor was the immediate
Jan 1, 1990
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Multiseam Mining On South African Collieries
By R. W. Hill
Multiseam mining has been carried out at many collieries in South Africa. It the seams are In close proximity difficult and dangerous mining conditions may arise. In the Witbank area multiseam bord an
Jan 1, 1995
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Estimating Rock Strengths Using Drilling Parameters During Roof Bolting Operations - Progress Report
By Yi Luo
Accurate mechanical and geological information of the roof strata is vital for roof bolting design in underground mines. In order to obtain such information in a timely manner, a research has been und
Jan 1, 2002
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Regional Horizontal Stress And Its Effect On Longwall Mining In The Northern Appalachian Coal Field
By D. W. H. Su
This paper presents the results of ill situ horizontal stress measurements using a Minifrac system in several northern Appalachian coal mines. The effect of stress magnitude and orientation on longwal
Jan 1, 1995
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The Broken Rock Zone Around Tunnels And Its Support Theory
By Fangting Dong
The broken rock zone (BRZ) and the tunnel support theory are investigated. The relationship between the BRZ and the related factors, the interaction between the BRZ and supports, and the function of s
Jan 1, 1988
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Optimization Of District-Wide Mine Layout In Multi-Seam Mining: A Case Study
By Huamin Li
Mine # 8 of Pindingshan Coal Group, Henan Province, China has an annual production 2 million metric tons. But it encounters many problems, e.g. mine layout is complicated, roadway maintenance is diffi
Jan 1, 2000
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Reinforcement of Large Pillars by Bolting (8821999e-4c04-46db-a69e-e7a56781ac96)
By S. J. Mitchell
An analysis of bolting reinforcement of several large [approximately 18 m (60 ft) cube] pillars was performed. The many overcoring stress profiles in pillars at the mine were used to produce generaliz
Jan 1, 1984
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Simulated Materials Modeling And Analysis Of The Overburden Strata Movement In Top Coal Caving Mining
By Zhou Ying
Based on the mining condition and roof lithology of the 2-3 coal seam at Gengcun Mine, the simulated materials modeling method was used to study the movement process and characteristics of overburden
Jan 1, 2001
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A Method for the Selection of Rock Support Based on Bolt Loading Measurements
By Stephen P. Signer
A method to assist in the evaluation and selection of roof bolts using in situ measurements of roof bolt loading has been developed by researchers of the Spokane Research Center, National Institute of
Jan 1, 1997
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Application of Yield-Lok Bolt for Bursting and Convergence Grounds in Mines
By Rocky Wu
Rock bursts are one of the greatest challenges to ground control in the mining industry. With increasing mining depth and mining scale, there are more and more industry requirements on yielding rock s
Jan 1, 2011
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Geo-Mechanical Property And Failures Of Weak Roof Shales In Coal Mines
By Yunqing Zhang
Weak shales refer to those with lower strength, thinly- laminated structure, sensitivity to moisture and weathering as well as significant time dependent behavior. It has been said that many future co
Jan 1, 2004
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Acoustic Scanner Analysis of Borehole Breakout to Define the Stress Field Across Mine Sites in the Sydney and Bowen Basins, Australia
By S. MacGregor
The role of horizontal stress, its orientation and magnitude, in defining the behaviour of strata in underground coal mines has been well established. Poor panel layouts have led to gate end stress co
Jan 1, 2002
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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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Continuing Development of Innovative Cable Support Systems
By John G. Oldsen
Passive cable bolting and active cable trusses have been used in roof support for more than two years Excellent roof control has been experienced by many coal operations. This paper covers the new
Jan 1, 1997
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Mitigating Subsidence Influences on Residential Structures Caused by Longwall Mining Operations
By Yi Luo
The severity of disturbances caused by longwall mining subsidence to various residential structures can be re¬duced. The success of such mitigation efforts depends on accurate subsidence prediction, c
Jan 1, 2003
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Downhole Overcoring Stress Measurement at a Western Underground Coal Mine
By David Conover
Knowledge of the magnitude and direction of the horizontal secondary principal stresses is a critical factor in designing the layout and mining sequence of underground openings. Typically, horizontal
Jan 1, 2004
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Evaluation Of Support Performance In A Highly Stressed Mine
By Hamid Maleki
The U.S. Bureau of Mines implemented a monitoring program in a western U.S. coal mine for the evaluation of both conventional and alternative support systems. The conventional support consisted of 2.5
Jan 1, 1994
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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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Mine-Wide Physical Property Trend Identification Using Portable Onsite Test Devices
By Thomas L. Vandergrift
The type and severity of coal mine entry failures are affected by the strength and stiffness properties of the roof, floor, end coal. Knowledge of the mine-wide trends of these properties Is valuable
Jan 1, 1990
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Development of a Risk Rating System for Use in Underground Coal Mining
By Johann van Wjk
Mandatory Codes of Practice to Combat Rock Fall Accidents came into force on South African Collieries in 1997. These were drawn up in accordance with guidelines issued by the Chief Inspector of Mines,
Jan 1, 2002