Research on overall stability of BS700 high-strength steel columns with box section

To study the overall stability of BS700 high-strength steel axially compressed columns with box section, the axial compression tests of 10 thin-walled box section columns were conducted in this paper, and the numerical calculation was completed using the finite element method. Moreover, the factor of initial geometric imperfections was considered during the processes of testing and analysis. The test results showed that the failure mode of BS700 high-strength steel columns with box sections was bending buckling. 1/1000 of the member length mentioned in the Code for Design of Steel structures (GB50017–2017) could be used as the maximum initial imperfection. Compared with the curves of the 3c type in the GB50017–2017 and Eurocode specifications, the long-column test results and finite element analysis results were evidently larger and close to those of 3b types in GB50017–2017 and Eurocode 3b (8% larger on average). Moreover, although the ANSI/AISC 360–10 specifications coincided well, this standard tended to be dangerous because it prescribed a relatively low slenderness ratio. Therefore, the curves of the 3b type stipulated in GB50017–2017 and Eurocode were recommended.