Structural performance evaluation on aluminum plates retrofitted with composite: Impact of hybrid (bonded/bolted) joining methods under the flexural loading

Hasan Ulus, Halil Burak Kaybal


Engineering materials lose their mechanical performance due to environmental loadings during service, and they require reinforcement. Recently, externally jointed metallic members have been regarded as an effective technique for strengthening structures thanks to the composites being light and having good mechanical properties. Although the traditional methods (bonded and/or mechanical joining) have been widely used for combining, hybrid joints have recently become popular to take advantage of the load transfer efficiency of both techniques.  On the other hand, it is essential to know which component the stress should be applied as a design criterion and how the damage behavior has changed accordingly. Since the member below the neutral axis is subjected to tensile and the upper is subjected to compressive stresses during bending loading, it is essential to understand how structural behavior is affected by the reinforcement in both cases. This work investigated the flexural behavior of bolted/bonded hybrid jointed aluminum-basalt composite, in the case of composite is below the neutral axis and aluminum below the neutral axis. Different damage modes were observed depending on different loading conditions and used joining techniques. Experiments indicate that applying the hybrid joining technique enhanced load-carrying capacity significantly attributed to bolts' restriction of shear deformation. This paper extends the understanding of aluminum retrofitting with composites and provides considerable suggestions for the joining method.


Aluminum, composite, bonded/bolted hybrid joint, epoxy, bending test

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Selcuk University Journal of Engineering Sciences (SUJES) ISSN:2757-8828

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