00000nam 2200000za 4500 9.840176 CaOODSP 20221107151758 cr ||||||||||| 170724s1966 oncad ob f000 0 eng d CaOODSP eng n-cn--- M38-8/20E-PDF M38-8/20 Coates, D. F., 1923- The mechanics of support and caving in longwall top-slicing [electronic resource] / D.F. Coates and M. Gyenge, Fuels and Mining Practice Division. Ottawa : Queen's Printer, 1966. 14 p. : charts, ill. Reprint series ; RS 20 Issued also in French under title: Mécanique du soutènement et du foudroyage dans l'exploitation en tranche unidescendante par longue taille. Cover title. "Reprinted from the Proceedings of the Fourth Intl. Conference on Strata Control and Rock Mechanics, Columbia University, New York, May 1964, pp. 70-84." Historical publication digitized from print 2017 [by Natural Resources Canada]. Includes bibliographical references. "The work described in this paper was done as part of a cooperative research project with a mining company that was in the process of examining various underground mining methods. It was decided, in view of the development of modern equipment, to conduct an experimental operation in top-slicing using a longwall configuration. In brief, a mat of timber and chain-link mesh was to be laid in an initial slice immediately under the pit waste that had been drawn down to this level by former block-caving operations. The mat would then be supported for subsequent slices by friction props. Basic information was needed on the distribution of stress around the mine opening together with its effects on the prop loads, the stability of the face, the stability of the underdrift, and the caving in the tail area. It was anticipated, that all of these technical factors could have some influence on operating efficiency and, in particular, that the handling of props would greatly influence costs. The mobility of lightweight props would do much to make the mining method economically feasible. On the other hand, the need for heavy props, and any difficulties in moving them, would make the method too costly for iron-ore mining. It was also considered possible that the increased stress in the longwall face resulting from arching over the mine opening might cause some caving in blast holes in this incompetent ore. This concentration of stress being transmitted below the mining area conceivably would, in addition, affect the stability of the conveyor drifts under the slice"--Introd., p. 1. gccst Mining industry gccst Rocks gccst Physics Gyenge, M. Canada. Natural Resources Canada. Canada. Department of Energy, Mines and Resources. Canada. Mines Branch. Mécanique du soutènement et du foudroyage dans l'exploitation en tranche unidescendante par longue taille (CaOODSP)9.840244 Reprint series - Dept. of Energy, Mines and Resources, Mines Branch ; RS 20 (CaOODSP)9.834843 PDF 4.70 MB https://publications.gc.ca/collections/collection_2017/rncan-nrcan/M38-8/M38-8-20-eng.pdf 300099