Improvement of structural characteristics of composite thin-walled beams using variable stiffness concept via curvilinear fiber placement

Farsadi T., Bozkurt M. O., ÇÖKER D., KAYRAN A.

Proceedings of the Institution of Mechanical Engineers, Part G: Journal of Aerospace Engineering, vol.235, no.14, pp.2017-2032, 2021 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 235 Issue: 14
  • Publication Date: 2021
  • Doi Number: 10.1177/0954410020988240
  • Journal Name: Proceedings of the Institution of Mechanical Engineers, Part G: Journal of Aerospace Engineering
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Aerospace Database, Applied Science & Technology Source, Communication Abstracts, Compendex, INSPEC, Metadex, Civil Engineering Abstracts
  • Page Numbers: pp.2017-2032
  • Keywords: Composite thin-walled beam, variable stiffness concept, curvilinear fiber path, wing box, structural characteristics, DYNAMICS, INPLANE, DESIGN, PANELS
  • Middle East Technical University Affiliated: Yes


© IMechE 2021.This study presents the use of variable stiffness concept via curvilinear fiber placement to achieve improved structural characteristics in composite thin-walled beams (TWBs). The TWB used in the study is constructed in circumferentially asymmetric stiffness (CAS) configuration. The variation of fiber angles along the span and the width of the TWB is included by defining two fiber path functions. A parametric study is performed to investigate the effects of different fiber paths on the structural performance metrics including frequency spacing, unit twist, and critical buckling load. For this purpose, a semi-analytical solution method is developed to conduct free vibration, deformation, and buckling analyses of the TWB with curvilinear fibers. The semi-analytical method is validated with several finite element (FE) analyses performed using ABAQUS. Elastic stress analyses of TWBs with selected fiber paths subjected to simplified distributed loading are also conducted using the FE method, and a ply failure criterion is applied to evaluate the strength of these TWBs. Overall results show that curvilinear fiber placement varied along the span leads to greater structural performance for a composite TWB than the straight fiber configuration.