Abstract:
Layered composite rocks (abbreviated as LCRs) are frequently encountered in rock engineering, and it is difficult to predict whether the stress-induced crack propagates through the layers or is contained within a layer when subjected to external loads. There was limited advanced knowledge of the crack propagation mechanism of flawed LCRs because the previous research mainly focused on the single lithologic layer. This study conducts uniaxial compression tests on weaker and stronger interbedded sandstone with pre-existing flaws. The crack propagation process of two-layer weaker and stronger interbedded sandstone specimens is studied using acoustic emission (abbreviated as AE) and digital image correlation (abbreviated as DIC) techniques, with the focus being on the influences of the flaw position. The results indicate that the crack initiation mode and final failure mode of weaker and stronger interbedded sandstone are dominated by the tensile mechanism. Three crack initiation modes are identified, which are closely related to the flaw position. When the flaw exists inside the weaker layer or the flaw is far away from the interface, the crack initiation mode is the tensile anti-wing crack initiation from the flaw tip. Whatever the flaw positions, the upward-propagating cracks arrest within the stronger layer, but the downward-propagating cracks eventually cross the weaker layer, which is the main mechanism causing failure. This study sheds light on the failure mechanism of LCRs considering the flaw position under uniaxial compression.
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GEOTECHNICAL AND GEOLOGICAL ENGINEERING
ISSN: 0960-3182
Year: 2024
Issue: 7
Volume: 42
Page: 6501-6521
1 . 7 0 0
JCR@2023
CAS Journal Grade:4
Cited Count:
SCOPUS Cited Count:
ESI Highly Cited Papers on the List: 0 Unfold All
WanFang Cited Count:
Chinese Cited Count:
30 Days PV: 3