TITLE:
Influence of Water Injection Fracturing on Crack Damage in Soft Coal and Application in Gas Extraction
AUTHORS:
Zhirong Wang, Jianshi Jin, Zhongyang Hang, Xiangzhi Hu
KEYWORDS:
“Three Soft” Coal Seam; Directional Water Injection Fracturing; Crack Damage; Gas Extraction
JOURNAL NAME:
Journal of Power and Energy Engineering,
Vol.2 No.4,
April
9,
2014
ABSTRACT: In order to study the hypotonic
and rheological particularity of “three soft” coal seam in west Henan, China,
this paper explored the stress and damage characteristics of crack in coal
under condition of water injection fracturing based on ABAQUS platform; The
cohesive element in T-P damage evolution criterion was used to describe the
approximately linear relationship between crack width and extending distance in
soft coal. The simulation results show that stress evolution and crack damage
in soft coal is a gradually developing process under condition of water
injection fracturing. When the static pressure is 4 - 10 MPa, and the injection
time is about 1 - 2 hours, the damage range of crack in soft coal can basically
reach an ideal data of 80 - 100 m, and then greatly improve the hypotonic
performance of “three soft” coal seam.