Influence of Rigid Inserts on Shear Modulus and Strength of Sandwich Beams with Polyurethane Foam as Core

In the present work, core shear modulus and flexural rigidity of sandwich panels with three different densities ranging from 100 to 300 kg/m(3) and with two different thicknesses ( 8 and 6 mm) of polyurethane foams separated by glass fiber bi-woven impregnated with epoxy resin as facings have been experimentally determined as per ASTM C 393 and analyzed in the light of data obtained by other researchers. The influence of different volume fractions (0.1 and 0.2) of rigid inserts made of polyurethane foam of 900 kg/m(3) density between facing and core at beam center on core shear modulus have been examined. The results have also been analyzed with core shear modulus obtained from direct shear test. Also, the failure modes of the sandwich panels and the corresponding strengths of the sandwich panels tested have been analyzed in detail. The influence of rigid inserts on the failure mode and strength of the sandwich panel has also been investigated.