ABSTRACT
Polyurea-coated structures have gained significant attention in recent times due to their ability to mitigate impact and blast-related events. In the majority of works published so far, the bonding between polyurea and the substrate on which it is coated is assumed to be perfect. However, it is imperative to take into account the possibilities of imperfect bonding between the two dissimilar materials and study the response of such bilayers subjected to impact. In the present study, we attempt to develop models that capture the rate-dependent nature of polyurea–steel interaction through cohesive zone methodology. It is observed that not only the bulk polyurea but also the interface between the polyurea and the steel is rate dependent and has an interesting feature in traction-separation law, especially at higher strain rates (3 s–1). We developed a modified cohesive zone model that fits the experimental J-integral data available in the literature. Furthermore, a numerical method of simulating the rate-dependent delamination behaviour of the polyurea–steel interface is developed to match the experimental J-integral data. This numerical method can be used for further analyses in studies on the effects of delamination on the impact response of polyurea-coated steel plates.
