A finite element based analysis of double strap bonded joints with CFRP and aluminium

A finite element based analysis of double strap bonded joints with CFRP and aluminium, Biscaia, Hugo, Cardoso João, and Chastre Carlos , 16th International Conference on Fracture and Damage Mechanics, Florence, Italy, (2017) copy at https://docentes.fct.unl.pt/cmcr/publications/finite-element-based-analysis-double-strap-bonded-joints-cfrp-and-aluminium-0


The bonding between two different materials or between same materials is a quite popular method. Unlike fastener joints, it avoids undesirable stress concentrations and doesn't demand an intrusive application to ensure the good performance of the joint. However, depending on the configuration of the adhesively bonded joint, its performance responds differently and the choice (if possible to make) on the best configuration, i.e. the configuration that originates the highest strength and/or stiffness, may be hard to make. Within this context, several configurationsof aluminium-to-aluminium bonded joints unstrengthened and strengthened with fiber reinforced polymers (FRP) were modelled using a commercial finite element code. The linearity and nonlinearity of the FRP composite and the aluminium were considered, respectively, and the adhesively bonded joints were subjected to a regular displacement that intended to simulate a tensioning load. Also, the nonlinearities of the interfaces were considered in the form of nonlinear cohesive adhesive laws. The fracture Modes I and II were defined trough a bond-slip relation with abi-linear shape and the Mohr-Coulomb failure criterion is used for the coupling of the cohesive adhesive laws of the interface when the debonding process of the bonded joint configuration implies the interaction between both fracture modes, i.e. the joint is under a mixed-mode (Mode I+II) situation. The results are presented and discussed and the configurations of the bonded joints are all compared through bond stress distributions and load-slip responses. The study herein presented is, therefore, a contribution to the analysis of the structural integrity of bonded joints between FRP composites and aluminium substrates, helping also on the choice of the most adequatebonded joint configuration and corresponding reinforcement to be used and applied in practice.


REFERENCES[1] H. Biscaia, C. Chastre, I. Borba, C. Silva and D. Cruz: Journal of Composites for Construction Vol. 20 (2015), 04015070.[2] H. Biscaia, C. Chastre and M.A.G. Silva: Composites Part B: Engineering Vol. 80 (2015), p. 246-259.[3] H. Biscaia, I. Borba, C. Silva and C. Chastre: Composite Structures Vol. 138 (2016), p. 52-63.