Numerical Analysis of the Stability Behaviour of Castellated Beams and Comparison to Regular Hot‐Rolled Profiles

Abstract Castellated steel beams, characterised by their unique perforated web design, have gained significant popularity in the construction of industrial and office buildings and medium‐span structures. They offer an economical solution due to their increased moment‐bearing capacity about the major axis with relatively low weight and associated high resource efficiency. However, they are particularly susceptible to lateral‐torsional buckling as a result of their increased cross‐sectional height. Additionally, the regularly spaced openings weaken the web, leading to further local failure modes. In the simplified design method, boundary conditions are incorporated through the elastic critical moment, which itself is influenced by possible local failure modes, such as web distortions. This paper investigates the influence of various boundary conditions on the analytical calculation of the elastic critical moment according to the draft Technical Report CEN/TR 1993‐1‐103:2023 and the lateral‐torsional buckling design according to the 2 nd Gen EN 1993‐1‐1:2022 for castellated steel beams in comparison to regular hot‐rolled profiles within a comprehensive numerical and analytical study.