A novel model of delamination bridging via Z-pins in composite laminates
File(s)
Author(s)
Allegri, G
Yasaee, M
Partridge, IK
Hallett, SR
Type
Journal Article
Abstract
A new micro-mechanical model is proposed for describing the bridging actions exerted by through-thickness reinforcement on delaminations in prepreg based composite materials, subjected to a mixed-mode (I-II) loading regime. The model applies to micro-fasteners in the form of brittle fibrous rods (Z-pins) inserted in the through-thickness direction of composite laminates. These are described as Euler-Bernoulli beams inserted in an elastic foundation that represents the embedding composite laminate. Equilibrium equations that relate the delamination opening/sliding displacements to the bridging forces exerted by the Z-pins on the interlaminar crack edges are derived. The Z-pin failure meso-mechanics is explained in terms of the laminate architecture and the delamination mode. The apparent fracture toughness of Z-pinned laminates is obtained from as energy dissipated by the pull out of the through-thickness reinforcement, normalised with respect to a reference area. The model is validated by means of experimental data obtained for single carbon/BMI Z-pins inserted in a quasi-isotropic laminate. © 2014 Elsevier Ltd. All rights reserved.
Date Issued
2014-06-22
Date Acceptance
2014-04-25
Citation
International Journal of Solids and Structures, 2014, 51 (19-20), pp.3314-3332
ISSN
1879-2146
Publisher
Elsevier
Start Page
3314
End Page
3332
Journal / Book Title
International Journal of Solids and Structures
Volume
51
Issue
19-20
Copyright Statement
© 2014, Elsevier. Licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International http://creativecommons.org/licenses/by-nc-nd/4.0/
Subjects
Composite materials
Fibre reinforced
Delamination
Toughness
Publication Status
Published