Numerical shape, thickness and stacking sequence optimisation and experimental study of hybrid composite plates under in-plane shear loading

Damghani, Mahdi; Matthews, Jason; Murphy, Adrian; Featherston, Carol

Abstract

Shape, thickness and stacking sequence optimisation of a damage tolerant hybrid (GFRP-CFRP) composite laminate is performed using the commercial Optistruct solver. The results of the optimisation study are compared to both a benchmark non-damage tolerant CFRP laminate (without protective surface GFRP plies known as type 1 laminate) and a damage tolerant traditionally optimised hybrid CFRP-GFRP laminate (having X shape CFRP plies known as type 2 laminate), designed and tested in a previous study. The optimised laminate is manufactured using three different manufacturing techniques. The experimental buckling and post-buckling performance of the manufactured laminates are investigated. The optimised hybrid laminate is approximately 8% heavier than the type 1 but 17% lighter than type 2, but with the benefit of protective surface GFRP plies in favour of a damage tolerant design as shown in a previous study. Both numerical and experimental buckling and post-buckling performance studies show that the optimised laminates demonstrate higher pre-buckling stiffness compared to the type 1 design. However, the experimental buckling and failure/collapse loads, unlike the numerically predicted loads, are 24.31% and 26.70% lower, respectively. This is due to the significant number of ply drop-offs in the hybrid laminate design, and hence geometric imperfections and stress concentration effects at these locations leading to early buckling and failure in the post-buckling region.

• Journal Article Type: Article
• Acceptance Date: Mar 13, 2023
• Online Publication Date: Mar 20, 2023
• Publication Date: May 1, 2023
• Deposit Date: Mar 15, 2023
• Publicly Available Date: Mar 22, 2023
• Journal: Structures
• Electronic ISSN: 2352-0124
• Publisher: Elsevier
• Peer Reviewed: Peer Reviewed
• Volume: 51
• Pages: 372-390
• DOI: https://doi.org/10.1016/j.istruc.2023.03.066
• Keywords: Free size optimisation; hybrid composites; Buckling; Post-buckling; shear loading
• Public URL: https://uwe-repository.worktribe.com/output/10553082
• Publisher URL: https://www.sciencedirect.com/science/article/pii/S2352012423003521