Weak form quadrature element analysis of sandwich panels with functionally graded soft-cores

Although many engineering sandwich panel theories are available, however, they cannot recover all stress components accurately for the sandwich panels with non-homogeneous functionally graded (FG) soft-cores. In this paper, a novel method is proposed to accurately analyze the static behavior of sandwich panels with FG soft-cores. Two combinations of boundary conditions and three types of loading are considered. Due to the severe transverse variations in the material properties and the discontinuity of the first order derivative of material parameters at the middle plane of the core, the problem is challenging for point discrete methods and thus is solved by the weak form quadrature element method (QEM). Based on the differential quadrature (DQ) rule, a novel quadrature sandwich panel element is established. Explicit formulations are worked out and the element can be implemented adaptively. Sandwich panels involving seven different core materials are investigated. The results are verified with ABAQUS data by using very fine meshes. Numerical results are presented to investigate effects of the power-law exponent of the material prosperities' variation, boundary conditions, and different types of loading on the distributions of displacement and stress of the sandwich panel with FG soft-core.