Bending Failure Behavior of Sandwich Beams Manufactured by Vacuum Infusion Process

Sandwich panels can fail in several ways under static bending loads. The face and core yield plastically or fracture depending on the span length or the nature of the material from which they are made. In this paper the static behavior of sandwich panels manufactured by vacuum infusion process has been experimentally investigated under three point bending loads. Composite sandwich beams were made by using E-glass fiber/polyester resin facing and a rigid PVC foam core. Flexural behavior under three point bending test for 9:1 and 19:1 aspect ratios (span length/thickness) for short and long beams are investigated, respectively. Results show that the shape of load-displacement curves in these two cases is significantly different. It was observed that the specimen failure mode changes totally with the change in the aspect ratio. For long beam, facing bending stress was 65% more than the short beam and core shear stress was 22% less than the short beam. Failure in short beam was due to core shear stress, while in the case of long beam it was due to the bending stresses of faces. Also, absorbed fail energy was determined from load and displacement values obtained during three point bending tests. The absorbed fail energy for short and long beam was 27885 and 12730 J, respectively

Keywords:

Sandwich Panel , Mechanical Properties , Three Point Bending , Absorbed Fail Energy , VIP