Inelastic axial-flexure-shear coupling in a mixed formulation beam finite element

SARITAŞ A., Filippou F. C.

INTERNATIONAL JOURNAL OF NON-LINEAR MECHANICS, vol.44, no.8, pp.913-922, 2009 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 44 Issue: 8
  • Publication Date: 2009
  • Doi Number: 10.1016/j.ijnonlinmec.2009.06.007
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.913-922
  • Keywords: Inelastic beam, Mixed formulation, Shear-locking, Axial-flexure-shear coupling, Shear yielding, BEHAVIOR
  • Middle East Technical University Affiliated: Yes


In this paper a beam element that accounts for inelastic axial-flexure-shear coupling is presented. The mathematical model is derived from a three-field variational form. The finite element approximation for the beam uses shape functions for section forces that satisfy equilibrium and discontinuous section deformations along the beam. No approximation for the beam displacement field is necessary in the formulation. The coupling of the section forces is achieved through the numerical integration of an inelastic multi-axial material model over the cross-section. The proposed element is free from shear-locking. Examples confirm the accuracy and numerical robustness of the proposed element and showcase the interaction between axial force, shear, and bending moment. (C) 2009 Elsevier Ltd. All rights reserved.