Mechanical behavior of resin pin-reinforced composite sandwich panels under quasi-static indentation and three-point bending loading conditions

This paper reports the mechanical behavior of resin pin-reinforced composite sandwich panels made from polyvinyl chloride core and glass/epoxy face sheets under indentation of a hemispherical indenter and three-point bending loading conditions. The goal was to study the effects of reinforcing parameters such as the number, arrangement, and diameter of the through-the-thickness resin pins on the indentation maximum load, the bending strength, and energy absorption characteristics of the tested samples under these loading conditions. The results revealed that using the resin pins to reinforce the polyvinyl chloride foam core led to increase the indentation maximum load up to 47%, and the maximum bending load up to 34%, compared to nonreinforced foam–core sandwich structures. Also, the presence of resin pins led to the change in the failure modes of specimens (i.e. from local to global deformation and failure) and consequently increased the energy absorption capability of sandwich structures by 31% and 68% respectively under indentation and bending loads.