MAIZI, Salah-Eddine2024-11-272024-11-272024https://dspace.univ-annaba.dz//handle/123456789/3679This thesis investigates the flexural behavior of innovative cold-formed steel (CFS) built-up closed sections, focusing on cross-sectional buckling failure. A Finite Element (FE) model is developed and extensively validated against various built-up closed and open sections in bending. Three parametric studies are conducted, each exploring different aspects of the proposed built-up closed sections.PDFencold-formed steel; built-up sections; flexural behavior; buckling failure; finite element analysis; direct strength method; generalized direct strength methodThesis