Experimental and Numerical Study of Press-Braked S690 High-Strength Steel Channel-Section Columns Failing by Minor-Axis Flexural Buckling

This paper reports an experimental and numerical investigation into the minor-axis flexural buckling behavior and capacity of press-braked S690 high-strength steel channel-section columns. The experimental investigation comprised initial geometric imperfection measurements and 10 pin-ended column tests. This was accompanied by a numerical modeling program, in which finite-element models were developed and validated against the test results and then adopted to perform parametric studies to generate further numerical data over a wide range of cross-section dimensions and member lengths. The obtained test and numerical data were adopted to assess the accuracy of the buckling curves, as given in the Eurocode, North American specification, and Australian/New Zealand standard, for press-braked S690 high-strength steel channel-section columns prone to minor-axis flexural buckling. Overall, it was found that the Eurocode buckling curve yields many conservative capacity predictions, whereas the buckling curves in the North American specification and the Australian/New Zealand standard lead to an overall good degree of design accuracy. A revised Eurocode buckling curve is proposed, and was shown to offer accurate capacity predictions for press-braked S690 high-strength steel channel-section columns prone to minor-axis flexural buckling.