In this paper, solutions for a transversely loaded simply supported case with several
different plate configurations based on extended higher-order sandwich panel theory
(EHSAPT) are outlined and numerical results are presented. The results are also
compared to established elasticity solutions and validation of EHSAPT for plates of
arbitrary aspect ratios is made. The results are also compared to existing classical
and first-order shear models for completeness. The results show excellent
agreement both for displacements and stresses through the core. Analytical
formulations and solutions to the natural frequency analysis of simply supported
composite sandwich plates are also presented. The effects of variation of
geometrical parameters of the structure on the natural frequency are also
studied.