The nonlinear transient thermoelastic analysis of functionally graded sandwich plates rested on partially elastic foundations

This paper presents a nonlinear transient thermoelastic analysis of functionally graded sandwich (FGSW) plates with a metal core and FGM skin layers resting on partially elastic foundations (p-EF). A refined first-order shear deformation theory (r-FSDT) combined with Kármán-type geometric nonlinearity is employed, formulated using a weak-form Q4 finite element. The study incorporates temperature conduction through the plate thickness and accounts for temperature-dependent material properties, capturing realistic thermal effects. The governing equations are derived via Hamilton’s principle and solved by the Newmark-β time integration method coupled with Newton–Raphson iteration. The proposed approach’s accuracy is verified against available benchmark solutions. The novelty of this work lies in systematically investigating the nonlinear transient response of FGSW plates under dynamic loading in the presence of p-EF, which has received limited attention in the literature. Furthermore, a detailed parametric study examines the effects of geometrical parameters, material properties, foundation characteristics, and boundary conditions (BCs) on the dynamic behavior of FGSW plates.