Analysis of Laminated Sandwich Plates Based on an Improved Higher Order Zigzag Theory

A finite element model based on an improved higher order zigzag plate theory developed by the authors is refined in this study and applied to bending and vibration response of soft core sandwich plates. The theory satisfies interlayer transverse shear stress continuity including transverse shear stress free condition at the plate top and bottom surfaces and transverse normal compressibility of the core. The in-plane displacements vary cubically through the entire thickness, while transverse displacement is assumed to vary quadratically within the core. In order to have a better computational benefit, a C ⁰ finite element formulation is adopted. This is refined through satisfaction of certain constrains variationally using a penalty function approach. The performance of the model is demonstrated by comparing the present results with 3D elasticity solutions and other available results.