Microcracking in tensile fracture of a brittle rock

Published on Jun 15, 2021in Engineering Fracture Mechanics3.426
· DOI :10.1016/J.ENGFRACMECH.2021.107789
Xiaoran Wang (CUMT: China University of Mining and Technology), Pouyan Asem6
Estimated H-index: 6
(UMN: University of Minnesota)
+ 1 AuthorsJoseph F. Labuz32
Estimated H-index: 32
(UMN: University of Minnesota)
Abstract Acoustic emission (AE) and digital image correlation were used to monitor mode I fracture in center notch and smooth boundary specimens. The AE source was characterized as a microcrack and represented by the moment tensor, which was obtained by minimizing the error between displacements calculated from an elastodynamic solution and those measured, subjected to the constraint of a microcrack source. Results showed that microcracking was locally mixed-mode dominant because of oblique microcrack planes within a tortuous fracture. However, the microcrack mechanisms decomposed in the global coordinate system indicated mainly mode I opening with modes II and III ten times smaller.
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