Lateral-Torsional Instability and Biaxial Bending of Imperfect FRP I-Beams


  •   Jodi Knorowski

  •   Stella B. Bondi

  •   Zia Razzaq


This paper presents the outcome of a theoretical and experimental study of the behavior of Fiber Reinforced Polymer (FRP) I-beams exposed to lateral-torsional instability or when subjected to biaxial bending. Laboratory experiments involved the application of vertical and horizontal static loads to a 4 x 4 x ¼ in. I-beam with various lengths and the resulting deflections were recorded. Governing biaxial flexure and torsion differential equations were modified to account for the presence of initial imperfections and subsequently solved using a central finite-difference scheme. The theoretical predictions of the beam behavior were found to be in good agreement with what was observed in the laboratory.

Keywords: Biaxial, Fiber Reinforced Polymer, I-beam, Imperfect, Lateral-Torsional Instability.


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How to Cite
Knorowski, J., Bondi, S.B. and Razzaq, Z. 2022. Lateral-Torsional Instability and Biaxial Bending of Imperfect FRP I-Beams. European Journal of Engineering and Technology Research. 7, 6 (Nov. 2022), 29–34. DOI: