Study on the nonlinear vibration of tri-directional functionally graded sandwich plates partially supported by Pasternak foundation subjected to blast loading

This paper aims to explore and quantify the nonlinear vibration response of tri-directional functionally graded sandwich (3D-FGSW) plates partially supported by a Pasternak foundation (PF) subjected to blast loading (BL). A key objective is to develop a computationally efficient finite element framework capable of accurately capturing the complex behavior of 3D-FGSW plates. The studied configuration features a two-dimensional functionally graded material (2D-FGM) core between two three-dimensional functionally graded material (3D-FGM) face layers. Nonlinear geometric effects, including mid-plane stretching, are modeled using von Kármán-type assumptions, and the governing equations are formulated via Hamilton's principle within an improved first-order shear deformation theory (iFSDT). The accuracy and computational efficiency of the proposed method are validated through comparison with existing benchmark solutions. Subsequently, a comprehensive parametric study is carried out to examine the effects of geometric dimensions, material properties, foundation sizes, and boundary conditions (BCs) on the nonlinear vibration of 3D-FGSW plates. The findings of this work are expected to provide valuable insights for the design and manufacturing of advanced sandwich structures subjected to BL.