A finite element framework for modeling internal frictional contact in three-dimensional fractured media using unstructured tetrahedral meshes
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Published version
Author(s)
Nejati, M
Paluszny, A
Zimmerman, RW
Type
Journal Article
Abstract
This paper introduces a three-dimensional finite element (FE) formulation to accurately model the linear elastic deformation of fractured media under compressive loading. The presented method applies the classic Augmented Lagrangian(AL)-Uzawa method, to evaluate the growth of multiple interacting and intersecting discrete fractures. The volume and surfaces are discretized by unstructured quadratic triangle-tetrahedral meshes; quarter-point triangles and tetrahedra are placed around fracture tips. Frictional contact between crack faces for high contact precisions is modeled using isoparametric integration point-to-integration point contact discretization, and a gap-based augmentation procedure. Contact forces are updated by interpolating tractions over elements that are adjacent to fracture tips, and have boundaries that are excluded from the contact region. Stress intensity factors are computed numerically using the methods of displacement correlation and disk-shaped domain integral. A novel square-root singular variation of the penalty parameter near the crack front is proposed to accurately model the contact tractions near the crack front. Tractions and compressive stress intensity factors are validated against analytical solutions. Numerical examples of cubes containing one, two, twenty four and seventy interacting and intersecting fractures are presented.
Date Issued
2016-04-06
Date Acceptance
2016-03-17
Citation
Computer Methods in Applied Mechanics and Engineering, 2016, 306, pp.123-150
ISSN
0045-7825
Publisher
Elsevier
Start Page
123
End Page
150
Journal / Book Title
Computer Methods in Applied Mechanics and Engineering
Volume
306
Copyright Statement
© 2016 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org/
licenses/by/4.0/).
licenses/by/4.0/).
License URL
Sponsor
Technological Resources PTY Ltd
Commission of the European Communities
Grant Number
3100429469
309067
Subjects
Applied Mathematics
01 Mathematical Sciences
09 Engineering
Publication Status
Published