Assessment of the refined sinus plate finite element: Free edge effect and Meyer-Piening sandwich test

• A C1 6-node triangular FE for multilayered composite plates is presented.
• The approach is based on a high-order sine model including transverse normal effect.
• This FE has no numerical pathology (shear locking, spurious modes, …).
• The approach is assessed on its capability to capture steep stress gradient.

This paper deals with the assessment of a refined sinus model for multilayered composite plates in the framework of severe test cases to highlight the interest and limitations of such an approach. The present sinus model is enriched by higher-order terms for both in-plane and transverse displacements, and layer refinement. This kinematics allows us to exactly ensure both (i) the continuity conditions for displacements and transverse shear stresses at the interfaces between layers of a laminated structure, and (ii) the traction-free conditions at the upper and lower surfaces of the plates. The number of unknowns is independent of the number of layers. A C1 6-node triangular finite element implementation is proposed, which does not suffer any numerical pathologies.First, the present approach is assessed on its capability to capture the steep transverse stress gradients occurring in the vicinity of free edges and is also compared with models available in the literature. Then, a highly anisotropic sandwich structure proposed by Meyer-Piening is also addressed for further comparison.