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This paper reports an experimental and numerical investigation into the buckling behaviour and resistance of press-braked ferritic stainless steel slender channel section beam–columns under combined compression and minor-axis bending moment. An experimental programme was firstly performed, including material coupon tests, initial global and local geometric imperfection measurements and ten beam–column tests. The experimental programme was followed by a numerical modelling programme, where finite element models were developed and validated against the experimental results and then adopted to conduct parametric studies to generate additional numerical data. Based on the obtained test and numerical data, the existing design interaction curves, as set out in the European code, American specification and Australian/New Zealand standard, were evaluated and found to result in conservative and scattered resistance predictions. An improved design interaction curve, anchored to more accurate end points and featuring more appropriate shape, was then developed and shown to offer more accurate and consistent resistance predictions for press-braked ferritic stainless steel slender channel section beam–columns over the codified design interaction curves. Statistical analyses were also performed to confirm the reliability of the new proposal. • The behaviour of press-braked ferritic stainless steel slender channel section beam–columns was studied. • Ten beam–column tests were conducted. • FE models were developed to validate against the test results and then used to conduct parametric studies. • The codified design interaction curves were evaluated, revealing conservatism. • A new improved design interaction curve was developed. [ABSTRACT FROM AUTHOR]

Experimental and numerical studies on hot-rolled stainless steel channel sections subjected to combined compression and minor-axis bending moment have been conducted and are fully reported in the present paper. The testing programme included initial local geometric imperfection measurements and ten minor-axis eccentric compression (combined loading) tests. The numerical modelling programme comprised a validation study, where finite element models were developed and validated against the test results, and a series of parametric studies, where the developed finite element models were adopted to generate further numerical data over a wide range of cross-section dimensions and loading combinations. The experimentally and numerically obtained data were used to assess the accuracy of the design interaction curves for hot-rolled stainless steel channel sections under minor-axis combined loading, as given in the European code and American specification. The assessment results generally reveal that the design interaction curves provided in the main body of the two design codes lead to unduly conservative and scattered failure load predictions, mainly owing to the conservative end points (i.e. the cross-section compression and bending resistances), which are calculated without considering material strain hardening. The appendix of each design code also provides an alternative method that uses the continuous strength method to account for material strain hardening in calculating the end points of the design interaction curve, and is shown to result in much more accurate and consistent predictions of failure load for hot-rolled stainless steel channel sections under combined compression and minor-axis bending moment. • The behaviour of hot-rolled stainless steel channel sections under minor-axis combined loading is studied. • Ten eccentric compression tests on hot-rolled stainless steel channel section stub columns are conducted. • FE models are developed and validated against the test results and then used to conduct parametric studies. • The codified design interaction curves are assessed, indicating conservatism. • The CSM-based codified design interaction curves are shown to yield higher accuracy. [ABSTRACT FROM AUTHOR]

The global buckling behaviour of hot-rolled stainless steel channel section beam–columns under combined compression and minor-axis bending moment has been studied based on testing and numerical modelling and reported in this paper. A testing programme was conducted on ten hot-rolled austenitic stainless steel channel section beam–columns, with five buckling towards webs and the other five buckling towards flange tips. This was followed by a numerical modelling programme, in which finite element models were firstly developed and validated against the test results and then used to perform parametric studies to generate further numerical data over a wide range of cross-section dimensions, member effective lengths and loading combinations. The test and numerical results were adopted to assess the current design interaction curves given in the European code and American guide, both of which were found to result in inaccurate and scattered failure load predictions. The inaccuracy of the codified design interaction curves stems from the inaccurate end points (i.e. the member resistances under pure compression and pure bending) and the inappropriate shape. To address these shortcomings, a new design interaction curve was developed firstly through the adoption of more accurate end points and secondly through the derivation of a more proper shape. The proposed design interaction curve was shown to yield accurate and consistent failure load predictions for hot-rolled stainless steel channel section beam–columns. The reliability of the new proposal was also confirmed by means of statistical analyses. • The buckling behaviour of hot-rolled stainless steel channel section beam–columns is studied. • Ten beam–column tests were conducted. • FE models were firstly developed and validated against the test results and then adopted to perform parametric studies. • The codified design interaction curves were assessed, indicating inaccuracy. • A new design interaction curves was proposed, with the accuracy and reliability demonstrated. [ABSTRACT FROM AUTHOR]