Free vibration and dynamic response of sandwich composite plates with auxetic honeycomb core

Abstract

This paper deals with the free vibration and dynamic responses of composite sandwich plates. The sandwich plate has three layers in which two face sheets are made of isotropic material, and the core layer is made of auxetic honeycomb structures with a negative Poisson's ratio.  A smoothed finite element model based on the first-order shear deformation theory is established for the analysis purpose. In the model, only the linear approximation is necessary, and the discrete shear gap method for triangular plate elements is used to avoid the shear locking. The Newmark direct integration technique is used to capture the dynamic responses of the sandwich plates. The convergence study is made, and the accuracy of present results is validated by comparison with available data in the literature. The influence of geometrical parameters, material properties, and boundary conditions are explored and discussed. Numerical results show that auxetic materials have several different responses compared to conventional materials, and these behaviors are strongly influenced by the internal structure of the auxetic material.