Axial capacity of a novel cold-formed steel swaged section: Experimental tests and design

This paper reports a total of 101 experimental results on the axial behaviour of CFS columns having a swaged section at the end or in the middle of channels under a fixed-fixed boundary. For comparison, the equivalent CFS columns with plain sections were also tested; CFS columns with five different stud lengths and three different cross-sections were tested. It was found that compared to the plain sections, the average axial capacities of specimens having a swaged section are reduced by 5.5% for sections having the cross-section dimensions of 65 × 41.3 × 0.75 and 3.9% for sections of 100 × 50 × 0.95, respectively. For the columns with lengths of 1000mm, 1200mm, and 1400mm, their primary failure mode was global buckling. However, for short columns (with lengths of 150mm and 300mm), the dominant failure mode was local buckling. A comparison between the experimental results and direct strength method (DSM) predictions from the AISI S100-16 and AS/NZS 4600:2018 was conducted, indicating that the DSM is un-conservative by approximately 1.4% on average while predicting the axial capacities of CFS columns having a swaged section.