Complete transverse stress recovery model for linear shell elements in arbitrarily curved laminates. (15th November 2020)

• Record Type: Journal Article
• Authors: Daniel, Pierre M.; Främby, Johannes; Fagerström, Martin; Maimí, Pere
• Is Part Of: Composite structures. Volume 252(2020)
• Publication Date: 2020-11-15
• Subjects: Stress recovery -- Transverse stresses -- Delamination -- Linear shell elements -- Equivalent single-layer (ESL); Composite construction -- Periodicals; Composites -- Périodiques; 624.18
• DOI: 10.1016/j.compstruct.2020.112675
• Languages: English
• ISSNs: 0263-8223

Abstract

Highlights: The transverse stresses are recovered in conventional linear shell elements. The method is reliable under complex load cases in arbitrarily curved laminates. The method is compared to the Extended-2D and Hermitian iteration methods. An added term is proposed to the Extended-2D method to meet boundary conditions. Open possibilities to identify interlaminar failures in large linear shell models. Abstract: Out-of-plane failure is common in composite layered materials. Its detection in numerical simulations usually involves a high-level of spatial refinement which may lead to an excessive computational time for large structures. This paper presents a formulation for the recovery of the transverse stresses in conventional linear shell elements based on First-Order Shear Deformation Theory. Starting from the equilibrium equations, the proposed formulation allows the calculations to be made for arbitrary curvatures including variable ones. Compared to the Extended-2D method, it has the advantage of including all the contributions from the force and moment derivatives making it reliable in complex load cases. Several examples with different laminates, curvatures and loads are presented. The numerical results confirm the potential of the proposed method to be used both as post-processing tool for conventional models and as an enrichment criterion for adaptive modelling.