Abstract
Crack-like cohesive defect propagation within a plane orthotropic linear elastic layer is considered by assuming that the defect, and its growth under load, can be modeled as the evolving separation along a straight, predetermined nonlinear, nonuniform Needleman-type cohesive interface. The analysis exploits a general form of orthotropy rescaling originally developed for the displacement boundary value problem by Krenk (1979). It is shown that when the material is degenerate orthotropic (i.e.; ρ = 1, ρ is the orthotropic shear parameter) rescaling enables the determination of solutions from isotropic ones and, when the material is fully orthotropic, rescaling allows for solutions to be obtained from problems with the simpler cubic symmetry. (These are well known attributes of linear static sharp crack analysis, which depend on an alternative form of rescaling the traction boundary value problem (Suo, 1990; Suo et al, 1991).) The procedure is demonstrated by obtaining degenerate orthotropic response from isotropic solutions recently obtained by the authors in an investigation of both solitary as well as multiple cohesive defect interaction problems in layered systems under arbitrary loading (Nguyen and Levy, 2009, 2011). In order to obtain fully orthotropic solutions via rescaling, a novel integral equation formulation is developed based on exact infinitesimal strain elasticity solutions for rectangular domains composed of cubically symmetric media and subject to arbitrary loading. Explicit results are obtained for the simple edge notch bend configuration, chosen so as to shed light on the mechanisms of defect propagation in orthotropic layers. It is demonstrated that increasing the orthotropic stiffness ratio can precipitate a quasi-brittle defect growth response. Furthermore, it is well known that in a number of technically important problem geometries and loadings, static sharp crack solutions are only weakly dependent on shear parameter ρ enabling the estimation of fully orthotropic behavior from isotropic solutions (Suo et al, 1991). This result is shown to be true for nonlinear cohesive fracture analysis of the edge notch bend configuration analyzed in this study.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 1266-1284 |
| Number of pages | 19 |
| Journal | International Journal of Solids and Structures |
| Volume | 50 |
| Issue number | 9 |
| DOIs | |
| State | Published - Mar 1 2013 |
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Keywords
- Cohesion
- Debonding
- Defect
- Elasticity
- Fracture
- Integral equation
- Interface
- Layers
- Orthotropy
ASJC Scopus subject areas
- Mechanical Engineering
- Mechanics of Materials
- Materials Science(all)
- Condensed Matter Physics
- Applied Mathematics
- Modeling and Simulation
Cite this
Cohesive fracture of plane orthotropic layers. / Nguyen, Chien M.; Levy, Alan J.
In: International Journal of Solids and Structures, Vol. 50, No. 9, 01.03.2013, p. 1266-1284.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Cohesive fracture of plane orthotropic layers
AU - Nguyen, Chien M.
AU - Levy, Alan J
PY - 2013/3/1
Y1 - 2013/3/1
N2 - Crack-like cohesive defect propagation within a plane orthotropic linear elastic layer is considered by assuming that the defect, and its growth under load, can be modeled as the evolving separation along a straight, predetermined nonlinear, nonuniform Needleman-type cohesive interface. The analysis exploits a general form of orthotropy rescaling originally developed for the displacement boundary value problem by Krenk (1979). It is shown that when the material is degenerate orthotropic (i.e.; ρ = 1, ρ is the orthotropic shear parameter) rescaling enables the determination of solutions from isotropic ones and, when the material is fully orthotropic, rescaling allows for solutions to be obtained from problems with the simpler cubic symmetry. (These are well known attributes of linear static sharp crack analysis, which depend on an alternative form of rescaling the traction boundary value problem (Suo, 1990; Suo et al, 1991).) The procedure is demonstrated by obtaining degenerate orthotropic response from isotropic solutions recently obtained by the authors in an investigation of both solitary as well as multiple cohesive defect interaction problems in layered systems under arbitrary loading (Nguyen and Levy, 2009, 2011). In order to obtain fully orthotropic solutions via rescaling, a novel integral equation formulation is developed based on exact infinitesimal strain elasticity solutions for rectangular domains composed of cubically symmetric media and subject to arbitrary loading. Explicit results are obtained for the simple edge notch bend configuration, chosen so as to shed light on the mechanisms of defect propagation in orthotropic layers. It is demonstrated that increasing the orthotropic stiffness ratio can precipitate a quasi-brittle defect growth response. Furthermore, it is well known that in a number of technically important problem geometries and loadings, static sharp crack solutions are only weakly dependent on shear parameter ρ enabling the estimation of fully orthotropic behavior from isotropic solutions (Suo et al, 1991). This result is shown to be true for nonlinear cohesive fracture analysis of the edge notch bend configuration analyzed in this study.
AB - Crack-like cohesive defect propagation within a plane orthotropic linear elastic layer is considered by assuming that the defect, and its growth under load, can be modeled as the evolving separation along a straight, predetermined nonlinear, nonuniform Needleman-type cohesive interface. The analysis exploits a general form of orthotropy rescaling originally developed for the displacement boundary value problem by Krenk (1979). It is shown that when the material is degenerate orthotropic (i.e.; ρ = 1, ρ is the orthotropic shear parameter) rescaling enables the determination of solutions from isotropic ones and, when the material is fully orthotropic, rescaling allows for solutions to be obtained from problems with the simpler cubic symmetry. (These are well known attributes of linear static sharp crack analysis, which depend on an alternative form of rescaling the traction boundary value problem (Suo, 1990; Suo et al, 1991).) The procedure is demonstrated by obtaining degenerate orthotropic response from isotropic solutions recently obtained by the authors in an investigation of both solitary as well as multiple cohesive defect interaction problems in layered systems under arbitrary loading (Nguyen and Levy, 2009, 2011). In order to obtain fully orthotropic solutions via rescaling, a novel integral equation formulation is developed based on exact infinitesimal strain elasticity solutions for rectangular domains composed of cubically symmetric media and subject to arbitrary loading. Explicit results are obtained for the simple edge notch bend configuration, chosen so as to shed light on the mechanisms of defect propagation in orthotropic layers. It is demonstrated that increasing the orthotropic stiffness ratio can precipitate a quasi-brittle defect growth response. Furthermore, it is well known that in a number of technically important problem geometries and loadings, static sharp crack solutions are only weakly dependent on shear parameter ρ enabling the estimation of fully orthotropic behavior from isotropic solutions (Suo et al, 1991). This result is shown to be true for nonlinear cohesive fracture analysis of the edge notch bend configuration analyzed in this study.
KW - Cohesion
KW - Debonding
KW - Defect
KW - Elasticity
KW - Fracture
KW - Integral equation
KW - Interface
KW - Layers
KW - Orthotropy
UR - http://www.scopus.com/inward/record.url?scp=84875266332&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84875266332&partnerID=8YFLogxK
U2 - 10.1016/j.ijsolstr.2012.12.024
DO - 10.1016/j.ijsolstr.2012.12.024
M3 - Article
AN - SCOPUS:84875266332
VL - 50
SP - 1266
EP - 1284
JO - International Journal of Solids and Structures
JF - International Journal of Solids and Structures
SN - 0020-7683
IS - 9
ER -