Nonlinear dynamic analysis of geometrically imperfect multi-direction functionally graded graphene platelet reinforced composite plates with magneto-electro-elastic sheets subjected to blast load

Abstract

This study presents a semi-analytical method to investigate the nonlinear dynamic responses of a geometrically imperfect multi-direction functionally graded graphene platelets reinforced composite plate with magneto-electro-elastic coupling (MDFG GPLRC-MEE) under blast loads. The mechanical properties of the plate structure are tailored by adjusting the spatial distribution of graphene platelets (GPL) content in the core layer. The localised geometrical imperfections of the structure are introduced and modelled as an initial deflection of the plate in the form of products of hyperbolic and trigonometric functions. Three boundary conditions are considered for the plate with different combinations of the simply supported and clamped edges. Based on the third-order shear deformation theory (TSDT) and von Kármán nonlinearity, the equations of motion are derived according to Hamilton's principle. The Galerkin method is then used to reduce the system to a set of ordinary differential equations. The fourth-order Runge-Kutta approach is subsequently employed to address the dynamic behaviours of the structure subjected to blast load. After verification, parametric experiments are conducted to explore the influences of some key factors, including boundary conditions, damping ratios, the Winkler-Pasternak foundation moduli, geometrical imperfection configurations, GPL content and distribution, blast load parameters, and external electromagnetic potentials. The numerical results indicate that for MDFG GPLRC-MEE plates, incorporating more GPL in the middle portion of the plate provides superior blast impact resistance compared to structures with more GPL at the margins.