The influences of mode II loading on fracture process in rock using acoustic emission energy

Published on May 1, 2018in Engineering Fracture Mechanics3.426
· DOI :10.1016/J.ENGFRACMECH.2018.03.001
Qing Lin11
Estimated H-index: 11
(China University of Petroleum),
Dengtian Mao1
Estimated H-index: 1
(CNOOC Limited)
+ 1 AuthorsShiyuan Li2
Estimated H-index: 2
(China University of Petroleum)
Abstract The influences of mode II loading on fracture process in Berea sandstone were investigated by comparing mode I and mixed-mode fractures that were created by center and eccentric notch beams under three-point bending. Fracture process was characterized by Acoustic Emission (AE) and related energy. Experimental results show mode II loading does not affect the length of fully-developed fracture process zone and maximum value of AE energy. However, it affects the zone from reaching fully-developed stage, i.e., mixed-mode fracture before or at peak load, and mode I after the peak. It also breaks the similarity and symmetry of AE events pattern.
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