TY - JOUR
TI - Coal permeability and crack distribution characteristics in unloading confining pressure experiments under different water pressures
AU - Tan Qiang
AU - Zhang Ru
AU - Gao Mingzhong
AU - Liu Qianying
AU - Zhang Zetian
AU - Jia Zheqiang
JN - Thermal Science
PY - 2017
VL - 21
IS - 11
SP - 241
EP - 249
PT - Article
AB - 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.