Novel Curvilinear 2|3D Unified Finite Element Formulations for the Analysis of Complex Shell Structures

Novel Curvilinear 2|3D Unified Finite Element Formulations for the Analysis of Complex Shell Structures

Piero CHIAIA, Maria CINEFRA, Erasmo CARRERA

Abstract. In this paper, a detailed locking analysis of novel curvilinear finite element models for the analysis of shells is proposed. In the introduced methodology, novel higher-order shell models are proposed in a non-orthogonal reference frame, recovering the classical Cartesian description via a consistent transformation law. The shell models are defined within the well-established Carrera Unified Formulation (CUF) framework, by which Lagrange-based theory of structures are merged with classical finite element interpolation of the reference mid-surface, obtaining novel shell elements with enhanced three-dimensional geometrical modeling capabilities. By exploiting the computational efficiency of 2D models, these novel 2|3D elements are now being adopted in locking investigations to assess the accuracy and capabilities of the proposed approach when complex structural problems are addressed. The methodology is validated by analyzing classical numerical benchmarks and patch tests proposed in the literature.

Keywords
Curvilinear Models, Shell Models, Variable Thickness, Variable Curvature

Published online 7/20/2026, 6 pages
Copyright © 2026 by the author(s)
Published under license by Materials Research Forum LLC., Millersville PA, USA

Citation: Piero CHIAIA, Maria CINEFRA, Erasmo CARRERA, Novel Curvilinear 2|3D Unified Finite Element Formulations for the Analysis of Complex Shell Structures, Materials Research Proceedings, Vol. 69, pp 1304-1309, 2026

DOI: https://doi.org/10.21741/9781644904251-226

The article was published as article 226 of the book CEAS – AIDAA Conference 2025

Content from this work may be used under the terms of the Creative Commons Attribution 3.0 license. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.

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