Skip to content

On the accuracy of localised 3D stress fields in tow-steered laminated composite structures

Research output: Contribution to journalArticle

Original languageEnglish
Article number111034
Number of pages23
JournalComposite Structures
Volume225
Early online date30 May 2019
DOIs
DateAccepted/In press - 22 May 2019
DateE-pub ahead of print (current) - 30 May 2019
DatePublished - 1 Oct 2019

Abstract

Variable Angle Tow (VAT) composites offer increased freedom for tailoring material properties compared to traditional straight-fibre composites. This increased freedom leads to greater design flexibility for enhanced structural performance but comes at the cost of more complex, spatially-varying displacement, strain and stress fields. To maximise the utility of VAT composites, a computationally efficient, yet accurate, numerical framework is needed. To this end, we employ a modelling approach that builds upon the recently developed, hierarchical Serendipity Lagrange finite elements. Three-dimensional (3D) stress distribution is obtained using the present modelling technique and verified against 3D finite element solutions, as well as other formulations available in the literature. A key advantage of the present approach is the ability to predict accurate 3D stress fields efficiently, i.e. with reduced computational effort, including around local features such as geometric, kinematic or constitutive boundaries. Moreover, the present work concerns the peculiarities of commonly used mathematical expressions for describing spatially varying fibre orientations across VAT laminates. The presence of an absolute value in the function used to describe fibre orientation can lead to discontinuities in fibre angle slope and curvature. In turn, these discontinuities lead to mathematical singularities in the constitutive relations along the laminate. If this singularity is not appropriately modelled as a boundary of the continuum, but rather as an interior point of the continuum, stresses may be predicted inaccurately. Compared to other models in the literature, our method is capable of unveiling detailed 3D stresses readily and accurately also in the vicinity of this singularity.

    Structured keywords

  • Bristol Composites Institute ACCIS

    Research areas

  • Variable angle tow composites, 3D stress fields, Unified Formulation, Unified formulation

Documents

Documents

  • Full-text PDF (accepted author manuscript)

    Rights statement: This is the author accepted manuscript (AAM). The final published version (version of record) is available online via Elsevier at https://www.sciencedirect.com/science/article/pii/S0263822319303630 . Please refer to any applicable terms of use of the publisher.

    Accepted author manuscript, 2 MB, PDF document

    Embargo ends: 30/05/20

    Request copy

    Licence: CC BY-NC-ND

DOI

View research connections

Related faculties, schools or groups