Theoretical and Numerical Modeling of Rock Hysteresis Based on Sliding of Microcracks
File(s)
Published version
Author(s)
Nejati, M
Paluszny, A
Zimmerman, RW
Type
Conference Paper
Abstract
Nonlinearity and hysteresis are two key features of elastic rock deformation. This behavior can be attributed to the presence of cracks and crack-like voids. The hysteretic behavior of rocks is related to the concept of unrecovered energy. Two main processes lead to the existence of unrecovered energy in the sliding crack model: (i) the work of frictional forces and (ii) the strain energy trapped in the solid. In this paper, a theoretical and numerical analysis will be presented to extend the work of David et al. [1] to consider 3D penny-shaped cracks. A 3D finite element analysis is used to evaluate the sliding crack model numerically. In this approach, the penalty method is used to simulate the contact behavior of the crack faces. The stick-slip condition of the crack faces is simulated by employing the constitutive frictional law of Amontons. The results show that no residual strain is developed in the body containing randomly oriented cracks if one assumes a uniform stress over all the crack cells. The energy loss is therefore equal to the work of frictional forces on the crack faces.
Date Issued
2013
Date Acceptance
2013-06-23
Citation
Proceedings of the 47th U.S. Rock Mechanics/Geomechanics Symposium 2013, 2013, pp.573-581
ISBN
978-0-9894844-0-4
Publisher
American Rock Mechanics Association
Start Page
573
End Page
581
Journal / Book Title
Proceedings of the 47th U.S. Rock Mechanics/Geomechanics Symposium 2013
Copyright Statement
© 2013 ARMA, American Rock Mechanics Association
Source
47th U.S. Rock Mechanics/Geomechanics Symposium
Notes
Abstract: Nonlinearity and hysteresis are two key features of elastic rock deformation. This behavior can be attributed to the presence of cracks and crack-like voids. The hysteretic behavior of rocks is related to the concept of unrecovered energy. Two main processes lead to the existence of unrecovered energy in the sliding crack model: (i) the work of frictional forces and (ii) the strain energy trapped in the solid. In this paper, a theoretical and numerical analysis will be presented to extend the work of David et al. [1] to consider 3D penny-shaped cracks. A 3D finite element analysis is used to evaluate the sliding crack model numerically. In this approach, the penalty method is used to simulate the contact behavior of the crack faces. The stick-slip condition of the crack faces is simulated by employing the constitutive frictional law of Amontons. The results show that no residual strain is developed in the body containing randomly oriented cracks if one assumes a uniform stress over all the crack cells. The energy loss is therefore equal to the work of frictional forces on the crack faces.
Publication Status
Published
Start Date
2013-06-23
Finish Date
2013-06-26
Coverage Spatial
San Francisco, CA