Computational Modelling of Delamination and Disbond in Adhesively Bonded Joints and the Relevant Damage Detection Approaches

Fiber reinforced polymer (FRP) composites are now widely used in various industrial applications. Due to their numerous positive attributes, FRPs are used to fabricate new structural components, and are also employed for repair and rehabilitation of older in-service structural components. In addition, adhesives are now considered as the preferred means for joining FRP structural components to one another, and to other materials. However, despite the excellent attributes of FRPs, such as lightweight, high specific stiffness and strength, structural elements made of FRPs are susceptible to inter-ply defects (referred to as delaminations), which could arise from various causes and factors. A small delamination in such structural components could propagate into severely large damage zone, thus compromising the structural integrity. A defect in an adhesively bonded joint would also follow a similar pattern; therefore, the detection of delaminations in FRPs, and disbonds in adhesively bonded joints, is a very important and critical issue. It also consumes considerable effort and cost in the life-cycle of such structures. Therefore, not only is it very important to detect such flaws at an early stage, but understanding of the post-damage response of such systems is also very important and challenging. This paper reviews some of the approaches used in dealing with the abovementioned issues. It also briefly discusses the relevant recent advancements, and presents some case studies, which would enable the reader to better appreciate the discussed approaches, with an emphasis on computational methodologies.