Buckling behavior of cold-formed steel sigma and lipped channel section beam-columns: Experimental and numerical investigation

Yılmaz Y., Öztürk F., Demir S.

Journal of Constructional Steel Research, vol.214, 2024 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 214
  • Publication Date: 2024
  • Doi Number: 10.1016/j.jcsr.2024.108456
  • Journal Name: Journal of Constructional Steel Research
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Academic Search Premier, Aerospace Database, Communication Abstracts, Compendex, INSPEC, Metadex, Civil Engineering Abstracts
  • Keywords: AISI-S100, Beam-column members, Cold-formed steel (CFS), Finite element analysis (FEA), Lipped channel section, Monotonic loading, Sigma channel section
  • Karadeniz Technical University Affiliated: Yes


In this study, the buckling behavior of cold-formed beam-column members with sigma and lipped channel sections under the combined effect of axial load and biaxial bending moment (P-Mx-My) was compared. A total of 30 specimens (15 with sigma sections and 15 with lipped channel sections), each measuring 1500 mm in length, were tested under monotonic loading. The performances of the specimens under eccentric loading such as strength and energy absorption capacity were investigated experimentally and numerically. The local, distortional and global buckling modes that determine the bearing capacity of the section and the length of the sigma and lipped channel member where all these buckling modes can be seen were determined. Finite element analysis (FEA) was performed with Abaqus software, and the numerical results were verified against experimental results. Using the validated finite element model, a comprehensive parametric study was carried out by performing 2894 FEA on sigma and lipped channel section members with various cross-sectional dimensions and lengths. Experimental results show that there are significant differences in load bearing capacity, energy absorption capacity and buckling modes of sigma and lipped channel section members. In the FEA/ AISI-S100 code comparison made at the end of the parametric study, it was determined that differences occurred according to the lengths, cross-sectional properties and loading points of the members. It was determined that the error rate was safer when the lips were subjected to tensile stresses than when they were subjected to compressive stresses. Finally, it was determined that the FEA/AISI-S100 error rate decreased as the length of the sigma-section members increased.