Delamination assessment of composite curved angles using simplified FEA models build-up by 2-D layered shell elements

As widely known, an accurate analysis of the stress state across the thickness of a composite laminate requires the calculation of the interlaminar through-the-thickness stresses as well as the shear stress components at the layers' interfaces. These so-called out-of-plane stresses are the key parameters when defining the delamination strength of curved composite laminates, particularly when their radius of curvature and the thickness of the composite are of the same size order. Since the use of layered solid elements is far from a reasonable approach in practical design applications, based on the finite element analysis results obtained through the use of conventional layered shell elements, the purpose of this paper is to propose a simplified post processing approach that enable to predict the interlaminar stress components originated across the thickness of symmetrically balanced curved composite laminates under the combined action of axial forces, shear forces and bending moments applied in curvature plane. A benchmark analysis to provide a critical comparison between a reference finite element model constructed based on 3-D layered solid elements and a simplified model build-up by 2-D layered shell elements is also considered. (paper)