Web crippling behaviour of web-perforated sigma sections under interior-two-flange loading condition

• Published in: Journal of constructional steel research Vol. 229; p. 109462
• Main Authors: Weerasinghe, Hasini, Konthesingha, Chaminda, Nanayakkara, Anura, Poologanathan, Keerthan, Nawarathna, Tharindu
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.06.2025
• Subjects: Aluminium; Carbon steel; Cold-formed sigma sections; ITF load case web crippling; Stainless steel; Unified design equation; Web openings; Cold-formed sigma sections; ITF load case web crippling; Stainless steel; Unified design equation; Carbon steel; Aluminium; Web openings
• ISSN: 0143-974X
• DOI: 10.1016/j.jcsr.2025.109462

Despite the widespread structural applications, the web crippling response of web-perforated cold-formed (CF) Sigma sections remains unexplored. Hence, a combined experimental and numerical investigation was conducted under the present study to determine the web-bearing resistance of web-perforated CF steel, stainless steel and aluminium Sigma sections under the Interior-Two-Flange (ITF) load case. A total of 18 Sigma sections were tested and the results were used to develop and validate a finite element (FE) model. An extensive numerical investigation (480 FE models) was conducted to evaluate the effects of critical parameters on the web-bearing resistance of web-perforated CF Sigma sections. FE results were compared against the web crippling strength predictions of current design codes. Based on the limitations of the codified predictions, a novel unified design equation was developed for determining the web-bearing resistance of web-perforated CF steel, stainless steel and aluminium sections under the ITF loading condition. Moreover, comparisons were made between the web crippling resistance of web-perforated Sigma sections and identical lipped channel sections. •Investigated the web crippling response of web-perforated CFS, CFSS and CFAl Sigma sections.•Combined experimental and numerical investigations were conducted.•The results of the numerical study were compared with current codified predictions.•A new unified design equation was proposed considering the Interior-Two-Flange load case.•Compared the web crippling response of web-perforated lipped channel beams and Sigma sections.