Complete stress field in sandwich panels with a new triangular finite element of single-layer theory

An alternative to conventional three-dimensional solid elements or elements based on the layerwise (zig-zag) theory is an element based on a single-layer plate theory in which the weighted-average field variables capture the panel displacement and stress fields. This study presents a new triangular finite element for modeling thick sandwich panels based on a {3, 2}-order single-layer plate theory. It utilizes seven weighted-average field variables arising from the cubic and quadratic representations of the in-plane and transverse displacement fields, respectively. In order to satisfy the C1 interelement continuity requirement, this triangular sandwich element is developed by utilizing the hybrid energy functional.