In-situ coal strength determination -- Case studies

Book · Wed Nov 01 04:00:00 EST 1995

OSTI ID:124678

Unrug, K F; Zhang, Y J; Thompson, E; Zhou, J Q ^[1]

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1. Univ. of Kentucky, Lexington, KY (United States). Dept. of Mining Engineering

Strength is coal is one of the governing factors in size determination of mine pillars, and therefore affects the percentage of extraction and thus, utilization of reserves. Coal strength is also important from the subsidence control standpoint, where mine pillars with appropriate safety factors should be designed for long term stability. Determination of coal seam strength has been addressed through the extrapolation of the coal strength obtained from a small number of samples on the whole section of the seam. This procedure often gives unreliable results. Presented in this paper is a method of in-situ strength testing of coal, allowing for a realistic determination of seam strength. Results of a field case study dealing with the coal seam, where samples for the laboratory strength tests could not be obtained due to the dense cleat, are presented. However, in these conditions, the in-situ testing was successful. A comparison of both conventional and the in-situ pentameter method was carried out. It was found that the penetrometer data not only improve the accuracy of strength determination of the entire seam, but also prove to be much more cost effective than the conventional method on a per test basis.

• OSTI ID: 124678
• Report Number(s): CONF-950811--; ISBN 0-930284-56-9
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
COAL MINING
COAL SEAMS
DESIGN
EXPERIMENTAL DATA
GROUND SUBSIDENCE
KENTUCKY
MEASURING METHODS
MECHANICAL TESTS
ROCK MECHANICS
SIZING
STRATIGRAPHY
SUPPORT PILLARS
WEST VIRGINIA