Abstract
The effect of environmental and loading conditions on the degradation of Interlaminar Shear Strength (ILSS) of the carbon-epoxy composite specimens was studied. The hygrothermal conditions capture the synergistic effects of field exposure and extreme temperatures. A short beam shear test (SBST) was performed to determine the Interlaminar Shear Strength (ILSS) of environmentally aged composite specimens in accordance with ASTM D2344-84. Initially, a standard two-dimensional cohesive layer constitutive model was employed in order to simulate the experiment using an in-house FEA code (NOVA-3D). Numerical instabilities, encountered using the standard cohesive layer model, were overcome by incorporating viscoelastic regularization in the constitutive equations of the cohesive layer. This modification also enabled the analysis to continue beyond the point of peak failure load. The model was able to accurately simulate the load vs. displacement behavior of most of the SBST samples aged under various hygrothermal and synergistically applied stress conditions. Further, the effect of displacement rate on the ILSS of specimens was studied using NOVA-3D. The model indicated a strong dependence of viscoelastic cohesive strength on the displacement rate. Regrettably, the predicted rate dependence could not be verified experimentally.
This is a preview of subscription content, log in via an institution.
Buying options
Tax calculation will be finalised at checkout
Purchases are for personal use only
Learn about institutional subscriptionsAbbreviations
- ASTM:
-
American Society for Testing and Materials
- CFRC:
-
Carbon Fiber Reinforced Composite
- CFRP:
-
Carbon Fiber Reinforced Polymer
- Cij :
-
Cauchy-Green Tensor
- ε:
-
Strain
- FEA:
-
Finite Element Analysis
- Fij(t):
-
Deformation Gradient in the RVE at time t
- ILSS:
-
Interlaminar Shear Strength
- RVE:
-
Representative Volume Element
- SBST:
-
Short Beam Shear Test
- Tg :
-
Glass Transition Temperature of the Matrix
- UTS:
-
Ultimate Tensile Strength
- VARTM:
-
Vacuum-Assisted Resin Transfer Molding
- α:
-
Area Fraction in the RVE
- λ:
-
Principal Stretch in the RVE
- σM,cr :
-
Critical Von-mises equivalent stress
- {H}:
-
Hereditary Strain Vector
- [M(t)]:
-
Viscoelastic Stiffness Matrix
- [R]:
-
Rotation tensor
- [U]:
-
Stretch tensor
References
Allen DH, Searcy CR (2001) A micromechanical model for a viscoelastic cohesive zone. Int J Fract 107:159–176
Crossman FW, Mauri RE, Warren WJ (1978) Moisture altered viscoelastic response of graphite/epoxy composite. Adv Compos Mater Environ Effects ASTM STP 658:205–220
Cui W, Wisnom MR (1993) A combined stress-based and fracture-mechanics-based model for predicting delamination in composites. Composites 24:467–474
Gao YF, Bower AF (2004) A simple technique for avoiding convergence problems in finite element simulations of crack nucleation and growth on cohesive interfaces. Model Simul Mater Sci Eng 12:453–463
Goruganthu S, Elwell J, Ramasetty A, Nair AR, Roy S, Haque A, Dutta PK, Kumar A (2008) Characterization and modeling of the effect of environmental degradation on interlaminar shear strength of carbon/epoxy composites. Polym Polym Compos 16:165–179
Haj-Ali RM, Muliana AH (2003) A micromechanical model for the nonlinear viscoelastic behavior of laminated composites. Int J Solids Struct 40:1037–1057
Haque A, Mahmood S, Walker L, Jeelani S (1991) Moisture and temperature induced degradation in tensile properties of Kevlar-Graphite/epoxy hybrid composites. J Reinf Plast Compos 10:132–145
Malvern LE (1969) Introduction to the mechanics of continuous medium. Prentice-Hall, Englewood Cliffs
Patel SR, Case SW (2002) Durability of hygrothermally aged graphite/epoxy woven composite under combined hygrothermal conditions. Int J Fatigue 24:1295–1301
Riks E (1979) An incremental approach to the solution of snapping and buckling problems. Int J Solids Struct 15:529–551
Roy S, Reddy JN (1988) Finite-element models of viscoelasticity and diffusion in adhesively bonded joints. Int J Numer Methods Eng 26(11):2531–2546
Roy S, Wang Y (2005) Analytical solution for cohesive layer model and model verification. Polym Polym Compos 13(8):741–752
Roy S, Wang Y, Park LKM (2006) Cohesive layer modeling of time-dependent debond growth in aggressive environments. J Eng Mater Technol 128:11–17
Taylor DM, Lin KY (2003) Aging effects on the interlaminar shear strength of high-performance composites. J Aircr 40(5):971–976
Zhuang H, Wightman JP (1997) Influence of surface properties on carbon fiber/epoxy matrix interfacial adhesion. J Adhes 62(1–4):213–245
Acknowledgement
The authors would like to acknowledge the support of this work by the Construction Engineering Research Laboratory (CERL), US Army Engineer Research and Development Center (ERDC), under Army contract W9132T07C0025/STTR-Phase II.
Author information
Authors and Affiliations
Corresponding author
Editor information
Editors and Affiliations
Rights and permissions
Copyright information
© 2012 Springer Science+Business Media B.V.
About this chapter
Cite this chapter
Akepati, A.R., Nair, A.R., Roy, S., Haque, A., Dutta, P.K., Kumar, A. (2012). Environmental Degradation of Interlaminar Shear Strength in Carbon/Epoxy Composites. In: Jain, R., Lee, L. (eds) Fiber Reinforced Polymer (FRP) Composites for Infrastructure Applications. Strategies for Sustainability. Springer, Dordrecht. https://doi.org/10.1007/978-94-007-2357-3_3
Download citation
DOI: https://doi.org/10.1007/978-94-007-2357-3_3
Published:
Publisher Name: Springer, Dordrecht
Print ISBN: 978-94-007-2356-6
Online ISBN: 978-94-007-2357-3
eBook Packages: Earth and Environmental ScienceEarth and Environmental Science (R0)