Bending and free vibration analysis of functionally graded sandwich plates using the Refined Zigzag Theory

The increasing application of functionally graded materials in the aerospace structures requires the adoption of accurate modeling strategies. The original formulation of the Refined Zigzag Theory is here extended to the bending and free vibration analysis of sandwich plates embedding functionally graded layers, either as faces or core. Extensive numerical investigation shows the superior predictive capabilities of Refined Zigzag Theory over both First-order Shear Deformation Theory and Third-order Shear Deformation Theory, if compared with the reference three-dimensional elasticity or high-fidelity FEM solutions. In virtue of its accuracy and of the C-0-continuity requirement for shape functions, Refined Zigzag Theory can be adopted to formulate reliable and computationally efficient finite elements suited for large-scale analyses of both traditional and functionally graded structures.