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Comprehensive Ground Control Study of a Mechanized Longwall Operation - 2 Volume Set: Final Report - Volume 1.

NTIS: PB/262-475 Available for Reference At Bureau Libraries :151 pages
The objective of this study was to make strata control measurements on an operating longwall, from which engineering design values for structural parameters such as convergence in the face area and support load density, as function of the rate of mining and the strata properties, can be extracted. Instruments installed in the mine were borehole pressure cells, convergence recorders, horizontal roof strain indicators, differential floor movement systems, and lateral roof and floor movement systems. Instruments installed on the surface, above the instrumented longwall panels, consisted of a slope indicator system, a vertical bed settlement probe system, and a shear displacement system. A comprehensive surface subsidence study was conducted in conjunction with the instrumentation. In addition to the instrumentation and monitoring, special tests were conducted to determine the bearing capacity of the roof and floor rocks, in situ modulus of coal, roof and floor rocks, and response of borehole pressure cells to ground stress. This report describes the instrumentation work, special tests, and presents the data collected.
Publication Date
Document Type
CP; Final Contract Report;
Fiscal Year
NTIS Accession No.
NTIS Price
Identifying No.
OFR 5(1)-77
NIOSH Division
Source Name
NTIS: PB/262-475 Available for Reference At Bureau Libraries
Performing Organization
Harza Engineering Company
Page last reviewed: September 2, 2020
Content source: National Institute for Occupational Safety and Health Education and Information Division