Flexural behavior evaluation of PET foam core curved sandwich beam: Experimental study and numerical simulation

The objective of this paper was to investigate the behavior and failure mechanisms of curved sandwich beams (CSBs) under bending loads. The curved sandwich beams with glass fiber-reinforced polymer (GFRP) and polyethylene terephthalate (PET) foam core were initially fabricated. Experiments in three-point bending were then performed to understand the flexural behaviors including failure modes, load-bearing capacities, and load-displacement curves. The effects of various curvature radii and foam types on the failure modes of CSBs were clarified. It was found that the utilization of PET foam in CSBs resulted in a prevention of core shearing failure and a gradual decrease in load-displacement response. The results showed that the ultimate load-bearing capacity and stiffness of the CSBs decreased by 17.7% and 61.8%, with a curvature decreased from 1150 to 300 mm, respectively. Moreover, a numerical model was utilized to provide accurate predictions of the experimental failure modes and load-bearing capacities of CSBs. Parameter analysis were also developed to investigate the bending response caused by different geometric parameters of CSBs.