THERMAL SCIENCE

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Mechanical behavior investigation of Longmaxi shale under high temperature and high confining pressure

ABSTRACT
Triaxial compression tests are conducted on Longmaxi shale under high temperature and high confining pressure (HTHCP) condition corresponding to a depth of 3000 m for two typical bedding plane orientations (0° and 90°). It is found that the crack initiation stresses and crack damage stresses of the Longmaxi shale specimens with different vein orientations are different, reflecting that the inclination of the bedding plane has a nonnegligible influence on the microcrack initiation and propagation. In addition, the brittleness index of the Longmaxi shale with a bedding plane orientation of 90° is greater than that with an orientation of 0°, which confirmed that the brittleness index is related to the structural orientation under a HTHCP condition. Concerning the failure patterns, both the shear and tensile fracture modes has been observed.
KEYWORDS
PAPER SUBMITTED: 2018-08-23
PAPER REVISED: 2018-11-21
PAPER ACCEPTED: 2019-02-27
PUBLISHED ONLINE: 2019-05-26
DOI REFERENCE: https://doi.org/10.2298/TSCI180823219L
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