Failure process, mode and strength of unidirectional composite single lap bonded joints were investigated experimentally with respect to bonding methods, that is, co-curing with or without adhesive and secondary bonding.
Recently, experiments and simulations of single lap bonded joints and their application in a boat structure were presented [18].
The paper deals with material parameters identification of a flexible adhesive and the numerical simulation of its behaviour in a single lap bonded joint.
A methodology is presented for the failure prediction of the composite single lap bonded joints considering both the composite adherend and the bondline failures.
Three-dimensional and two-dimensional Digital Image Correlation (DIC) have been used to evaluate the evolution of deformation and strain in composite single lap bonded joints prior to failure.
Single lap bonded joints were produced with two commercial polymeric adhesives – epoxy (EP) and polyurethane (PUR) – and exposed to a mild (Mediterranean) range of thermal variations (−5 °C 40 °C) for up to 350 cycles in a dry condition.
The experimental procedures were composed by tests with: spot welding joints without adhesive, single lap bonded joints and hybrid joints combining both joining techniques – spot welding and adhesive bonding.
The model was developed on the basis of extensive experimental and numerical investigations, presented in the first [Quaresimin M, Ricotta M. Fatigue behaviour and damage evolution of single lap bonded joints in composite material.
Compos Sci Technol, 2006 66:176–87] and second [Quaresimin M, Ricotta M. Stress intensity factors and strain energy release rates in single lap bonded joints in composite materials. Compos Sci Technol, 2006 66:647–56] part of this work.
In the current study, 3D DIC was successfully used to measure full-field in-plane surface strains and out-of-plane surface deformations for composite single lap bonded joints (adherends manufactured from both fibre preimpregnated resin (pre-preg) and resin infused non-crimp-fabric (NCF)).
Considering some case studies derived from the current literature, consisting of shear-lap bond tests of curved masonry specimens characterized by different curvatures of the bonded surface and different strengthening configurations, the validation of the proposed approach is carried out.
