This paper analyzes the bending response of several sandwich plates with a
functionally graded core, using advanced equivalent single layer (ESL) and layerwise
(LW) models with linear to fourth-order expansion in the thickness direction. The
functionally graded properties of the core have been approximated by means of
Legendre polynomials. The ESL and LW theories have been developed according to
the
principle of virtual displacements and
Reissner’s mixed variational theorem; in
the latter case, both displacements and transverse shear/normal stresses have been
assumed as primary variables. Closed-form solutions for simply supported
sandwich plates loaded by a transverse distribution of harmonic pressure are
discussed. Various assessments have been made of the proposed theories with
respect to the available results. Our obtained results show that, depending
on the chosen functionally graded core, the use of advanced models may
turn out to be mandatory with respect to classical theories (for example,
first-order shear deformation theory). It has been shown that the use of a core
in functionally graded material can offer some advantages with respect to
the classical cores that have been widely employed in open literature. A
benchmark has been proposed which consists of a sandwich plate with two
isotropic faces (ceramic and metallic) and various functionally graded cores.
That benchmark could be useful in assessing future refined computational
models.
Keywords
functionally graded materials, sandwich plates with an FGM
core, Carrera's unified formulation, classical models,
mixed models, equivalent single layer theories, layerwise
theories, Legendre polynomials
