Modelling the cyclic inelastic behaviour of a dissimilar metal/composite bonded joint at low frequencies

The present paper is concerned with the investigation of the inelastic behaviour observed in load-unload cyclic tests performed at 50 degrees C in single lap joints composed of a polyurethane based composite reinforced with fibreglass bonded to an ASTM A1020 steel substrate using an epoxy adhesive. The experiments presented in this research show that the inelastic behaviour of the joint is strongly dependent on the load frequency, eventually leading the structure to exhibit a progressive deformation when submitted to load-unload cyclic loading. The main goal of this study was to propose a preliminary rate-dependent mechanical model capable to describe the cyclic inelastic behaviour for an arbitrary load-unload history at low frequencies and a reasonable agreement was obtained between the experimental results and the model predictions.

Automated summary

The present study investigates the inelastic behavior observed in load-unload cyclic tests of single lap joints composed of a polyurethane based composite reinforced with fiberglass bonded to an ASTM A1020 steel substrate using an epoxy adhesive at 50 degrees C. The experimental results demonstrate that the inelastic behavior of the joint greatly depends on the load frequency, leading to progressive deformation under load-unload cyclic loading. The main objective of this study was to propose a preliminary rate-dependent mechanical model that accurately describes the cyclic inelastic behavior for various load-unload histories at low frequencies, and there was a reasonable agreement between the experimental results and the model predictions.