Modelling the variability of skin stiffener debonding in post-cured top-hat stiffened panels

• Published in: Composite structures 2019-03, Vol.211, p.187-195
• Main Authors: Yetman, J.E., Sobey, A.J., Blake, J.I.R., Shenoi, R.A.
• Format: Article
• Language: English
• Subjects: Delamination; Fracture; GFRP; Material characterisation
• ISSN: 0263-8223; 1879-1085
• DOI: 10.1016/j.compstruct.2018.11.078

Glass structures are often used in industries utilising large structural topologies. These structures are typically manufactured by post-curing subcomponents together, using a chopped strand mat layer at the interface. To predict failure of these joints requires an accurate assessment of the material and fracture properties. In this paper two industrially manufactured top-hat stiffened panels are tested to determine the fracture behaviour at the component level. This highlights that the variability seen in fracture properties at coupon level is less evident in structural component response. Then a previously developed set of material properties is used to accurately model the structural response, crack initiation and debonding of the panels under four point bend using Finite Element Analysis which gives final failure at 6.2 kN and a 4.4% error compared to the experimental results which exhibits final failure at 5.94 kN. The specific fracture properties tested and R curve are shown to be critical in assessing crack initiation and propagation with considerable error, 14.5%, provided by data assumed from the literature.