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Title: Model studies to develop criteria of subsidence due to the room and pillar mining of coal

Conference · · Prepr., Soc. Min. Eng. AIME; (United States)
OSTI ID:6178378

Surface subsidence is a phenomenon mainly associated with longwall mining, although it can also occur if the coal pillar left to protect the surface deteriorates with time and results in the collapse of the room and pillar system. A method has been developed that utilizes physical mine models and laser holographic interferometry. This method is capable of measuring displacements as small as 5 microinches by means of generating displacement contours on a surface, even that of granular materials. Analysis of subsidence in room and pillar mining using models of various extraction ratios and overburden depths along with two different types of overburden model material (sand and gelatin) has been made. The sand represented the extreme brittle conditions of geologic material while the gelatin represented viscoelastic behavior of geologic material. This paper deals with the analysis of data which has been gathered up to date, and mainly associated with the use of sand as an overburden model material. The analysis included the effect of variation of geometric parameters on surface subsidence. Among these parameters are: variation in seam depth and thickness, surface and seam inclination, and extraction ratio.

Research Organization:
West Virginia University, Morgantown, West Virginia
OSTI ID:
6178378
Report Number(s):
CONF-840218-
Journal Information:
Prepr., Soc. Min. Eng. AIME; (United States), Vol. 84-92; Conference: 113. annual meeting of the American Institute of Mining, Metallurgical and Petroleum Engineers, Los Angeles, CA, USA, 26 Feb 1984
Country of Publication:
United States
Language:
English