Natural frequency analysis of a sandwich panel with soft core based on a refined shear deformation model

The natural frequency of a thick rectangular sandwich panel composed of orthotropic facesheets and a soft core was studied based on a refined shear deformation model. The shear deformation of the sandwich panel was described by a polynomial function. The effect of transverse shear modulus of the facesheets and core on flexural vibration of the panel was investigated. Comparison was made among classical thin plate theory, linear shear (low order) deformation theory and the refined shear (high order) deformation model. Results from finite element analysis were also provided to verify the theoretical predictions. It was shown that the refined shear deformation model provided a better prediction on the natural frequency of vibration of a sandwich panel than thin plate model or low order deformation model.