THERMAL SCIENCE

International Scientific Journal

COAL PERMEABILITY AND CRACK DISTRIBUTION CHARACTERISTICS IN UNLOADING CONFINING PRESSURE EXPERIMENTS UNDER DIFFERENT WATER PRESSURES

ABSTRACT
This paper addresses the mechanical behavior and permeability characteristics of the unloading coal under different water pressures in the TOP2518-comprehensive- rock-testing system. With the use of the computed tomography scan tests, the 3-D crack distribution characteristics of the fractured coal are obtained and reconstructed. The difference in the 3-D crack distribution of unloading coal induced by different water pressures is also analyzed in detail. The results show that, as the water pressure changes from 0 MPa to 8 MPa, the peak stress of unloading coal gradually decreases, and that the variation degree of permeability of the coal samples increases significantly comparing with the initial permeability.
KEYWORDS
PAPER SUBMITTED: 2017-03-10
PAPER REVISED: 2017-05-01
PAPER ACCEPTED: 2017-05-26
PUBLISHED ONLINE: 2017-09-09
DOI REFERENCE: https://doi.org/10.2298/TSCI170310195T
CITATION EXPORT: view in browser or download as text file
THERMAL SCIENCE YEAR 2017, VOLUME 21, ISSUE Supplement 1, PAGES [S241 - S249]
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© 2017 Society of Thermal Engineers of Serbia. Published by the Vinča Institute of Nuclear Sciences, Belgrade, Serbia. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International licence