Stress-strain hysteresis during hydrostatic loading of porous rocks
File(s)
Published version
OA Location
Author(s)
Biyoghe, Alvin T
Leroy, Yves M
Pimienta, Lucas
Zimmerman, Robert W
Type
Journal Article
Abstract
A micro-mechanical model is proposed to predict the stress–strain hysteresis during the cyclic hydrostatic loading of fluid-saturated rocks under drained or undrained conditions. A spherical pore is surrounded by a multi-cracked shell where local deviatoric stress develops despite the remote hydrostatic loading. The effective properties of the material composing the shell are constructed assuming an isotropic distribution of cracks with no interaction, and the overall properties thanks to the spherical assemblage approach. The fluid pressure in drained and undrained conditions is assumed to be uniform throughout the assemblage. A new analytical solution is proposed, assuming all cracks are closed and slipping either forwardly or reversely. It is shown with numerical simulations for drained conditions that this assumption is indeed respected for sufficiently small values of the crack friction angle. However, for reasonable values, the closed cracks during the unloading phase could slip in either direction: reversely close to the pore and still forwardly away from the pore. Moreover, at critical radii, the slip could occur in either direction depending on the crack orientation. A similar micro-structural response is observed for undrained conditions, although the remote confining stress required to close the cracks is much larger. The model’s predictions compare favourably with recent experimental data on dry sandstones and carbonates, which were presented in a study on the influence of strain amplitude on the transition between static and dynamic properties. The crack density and matrix elasticity modulus are sufficient fitting parameters to accurately predict the hysteresis loops, especially for porosity levels above 10%.
Date Issued
2024-12-01
Date Acceptance
2024-09-07
Citation
Journal of the Mechanics and Physics of Solids, 2024, 193
ISSN
0022-5096
Publisher
Elsevier
Journal / Book Title
Journal of the Mechanics and Physics of Solids
Volume
193
Copyright Statement
Crown Copyright © 2024 Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).
Identifier
10.1016/j.jmps.2024.105861
Subjects
ATTENUATION
CRACKS
DISPERSION
Frictional cracks
Hydrostatic loading
Hysteresis
Materials Science
Materials Science, Multidisciplinary
Mechanics
MODEL
Physical Sciences
Physics
Physics, Condensed Matter
POROELASTICITY
Porous media
Science & Technology
Spherical assemblage
Technology
Publication Status
Published
Article Number
105861
Date Publish Online
2024-09-10