Comparative study of the dynamic response between functionally graded sandwich plates and four-parameter FG plates

This paper presents an efficient higher-order theory for analyzing the dynamic behavior of two types of sandwich plates: functionally graded sandwich plates (FGSPs) and four-parameter functionally graded plates (FPFGPs). The FGSP consists of two functionally graded (FG) face sheets and a ceramic core. For FGSPs, the variation follows a power-law distribution, while for FPFGPs; it adheres to Tornabene's model. To ensure that transverse shear stresses vanish at the top and bottom surfaces of the FGSP, a trigonometric shear deformation theory is employed. This theory incorporates four displacement field variables with indeterminate integral terms. The governing equations are derived using Hamilton's principle and solved using the Navier solution method for simply supported boundary conditions. Validation results demonstrate excellent agreement between the proposed theory and existing literature. Additionally, a detailed parametric study highlights the influence of key geometric and mechanical parameters, including the power-law index, side-to-thickness ratio, and aspect ratio, on the dynamic behavior of the plates.