Bending Of Sandwich Plates Based On High-order Deformation Theory

Sandwich plates are widely used in any engineering application for its good mechanics characteristics. But there are more and more new sandwich structures with the development of material science, the theories build on the assumption of soft-core and first-order deformation cannot satisfy the needs of the engineering. The more precise models should be established. The major works of this paper are listed as follows.Based on Reddy high-order deformation theory and the assumption of Reissner, the equation for the bending problems of hard-core sandwich plates are given with considering the stiffness of core.According to the assumption of Hoff and the displacement pattern of higher-order shear deformation theory, the basic equation for the bending problems of hard-core sandwich plates are derived by the generalized potential energy principle.The example of hard-core sandwich plate on the simple support and under uniform load is used in this paper to study the influence of the elastic modulus of core and the thickness of sandwich plates. We can see the theory of this paper generally applies to soft-core and hard-core sandwich plates. In addition, it can show the affection caused by transverse shear effect.This high-order theory has been proved by numerical analysis in present paper. In addition, the limits of the existing finite element theory have been pointed out because the shell element of traditional finite element method was built on first-order theory.This paper aims to compare the typical sandwich theory, first-order theory and high-order theory from several aspects. Furthermore, the graph shows how the normal line deformation changes with the elastic modulus of core and the distribution of transverse shear strain is also given. Due to the shear damage is one of main forms of sandwich structures, it is necessary to take high-order theory in researching sandwich plates.