Parametric study of Sandwich Plates with Viscoelastic, Auxetic Viscoelastic and Orthotropic Viscoelastic Core Using a New Higher Order Global-Local Theory

In this paper, sandwich plates with flexible core and composite surfaces as well as viscoelastic and auxetic core are investigated under dynamic loading. A new higher order global-local theory is used for simulation of the dynamic behavior of sandwich plates. The presented theory is able to consider the thickness change of the sandwich plates as well as transverse stresses accurately. It is obvious that considering these parameters are so crucial in study behavior of thick sandwich plates or sandwich plates with soft core. Furthermore, in terms of solving equations, an iterative incremental method based on the formulation of transient nonlinear finite element as well as a real time algorithm was employed to simulate viscoelastic behavior accurately. The results indicate a significant increase in the stiffness of the sandwich plate due to the auxetic properties of the core materials, leading consequently to the reduction of the vibration amplitude and stresses level. Some of the innovations belonging to this paper are: 1) presenting a global-local higher-order theory while considering the changes in the thickness of the sandwich plates; 2) calculating transverse stresses using the three-dimensional elasticity method as well as modifying the results obtained from displacement and inertial effects based on this method; 3) simulating sandwich plate with viscoelastic and auxetic cores; 4) taking orthotropic properties for the viscoelastic core into account.