Experimental and numerical study on flexural behaviour of cold-formed steel hat-shaped beams with geometrical imperfections

• Published in: Journal of constructional steel research 2023-03, Vol.202, p.107774, Article 107774
• Main Authors: Aktepe, Rafet, Guldur Erkal, Burcu
• Format: Article
• Language: English
• Subjects: 3D laser scanner; Bending test; Cold-formed steel; Finite element modelling; Geometric imperfection; Hat section
• ISSN: 0143-974X; 1873-5983
• DOI: 10.1016/j.jcsr.2023.107774

Experimental and numerical studies are conducted to investigate cold-formed hat-shaped members' flexural behaviour and determine the effects of different parameters on the behaviour. A total of ten specimens of cold-formed hat-shaped beams with different lengths are chosen for physical tests. The actual geometry and geometric imperfection distributions are acquired by processing 3D point clouds obtained by laser scanners. Four-point bending tests are performed to obtain benchmark results for numerical models. It is observed that numerical results are in accordance with the experimental results with high accuracy. Once the generated finite element models are calibrated based on the experiment results, a parametric study investigating the influence of the length, thickness, lip width, return length, radius, and lip angle on the beam behaviour is undertaken. In addition, the effect of geometric imperfection magnitude selection and imperfection modelling method on the member capacity is considered. The study's outcomes show that the initial geometric imperfections and input parameters selected for the generated numerical models significantly affect the flexural behaviour of CFS hat-shaped beams. •Bending behaviour of CFS omega-sectioned members is investigated.•3D laser scanners are used to obtain geometric imperfection distributions.•A parametric study taking various geometric properties into account is carried out.•Equations are proposed for predicting capacity reduction factor due to corner radii.•Obtained geometric imperfections are compared with manufacturing tolerances.