An investigation of the causes of cutter roof failure in a central Pennsylvania coal mine: a case study.
Hill-JL III; Bauer-ER
Rock mechanics in productivity protection: proceedings of the twenty-fifth symposium on rock mechanics, June 25-27, 1984, Northwestern University, Evanston, Illinois. Dowding CH, Singh MM, eds. New York: Society of Mining Engineers of the American Institute of Mining, Metallurgical and Petroleum Engineers, 1984 Jun; :603-614
Bureau of Mines research in a coal mine of central Pennsylvania revealed a correlation between the occurrence of clastic dikes and formation of cutter roof failure. In-mine mapping of ground conditions showed an increase in roof failure in areas of high frequencies of clastic dikes. Rock pressure monitoring around clastic dikes registered the greatest amount of roof loading near the intersection of dikes with the rib. Load cells measuring horizontal pressure changes in the roof indicated that the greatest pressure changes were occurring perpendicular to entry headings when clastic dikes were present. Analysis of rock pressure monitoring showed that the roof behaved as two cantilever beams when severed by a clastic dike. Additional roof supports such as trusses and cribbing were found to effectively support the roof in areas of clastic dikes and prevent cutter roof failure. However, these methods were only successful when employed shortly after mining.
Mining-industry; Mining-equipment; Underground-mining; Coal-mining; Rock-falls; Rock-mechanics; Geology
OP; Conference/Symposia Proceedings
Rock mechanics in productivity protection: proceedings of the twenty-fifth symposium on rock mechanics, June 25-27, 1984, Northwestern University, Evanston, Illinois