Experimental and numerical study of press-braked S690 high strength steel slender channel section columns prone to local–flexural interactive buckling

• Main Authors: Zhang, Lulu, Zhao, Ou
• Other Authors: School of Civil and Environmental Engineering
• Format: Article
• Language: English
• Published: 2022
• Subjects: Engineering::Civil engineering; Design Codes; Local–Flexural Interactive Buckling
• Online Access: https://hdl.handle.net/10356/161843
• Institution: Nanyang Technological University

This paper reports an experimental and numerical investigation into the local–flexural interactive buckling behaviour and resistance of press-braked S690 high strength steel slender channel section columns. An experimental programme was firstly conducted and included initial geometric imperfection measurements and twelve pin-ended column tests. Interaction between local buckling and flexural buckling was observed for all specimens upon testing and discussed in detail. The experimental programme was accompanied by a numerical modelling programme, where finite element models were developed and validated against the test results and then employed to perform parametric studies to generate further numerical data over a wide range of cross-section dimensions and member effective lengths. The obtained test and numerical data were used to assess the accuracy of the codified design rules for press-braked S690 high strength steel slender channel section columns failing by local–flexural interactive buckling, as set out in the European code, North American specification and Australian/New Zealand standard. The assessment results revealed that the European code leads to excessively conservative and scattered resistance predictions, while the North American specification and Australian/New Zealand standard result in a higher level of design accuracy and consistency, but still with many conservative resistance predictions for columns with short to intermediate lengths. Finally, a new design approach was proposed and shown to yield substantially more accurate and consistent resistance predictions for press-braked S690 high strength steel slender channel section columns over the design codes.