Assessment of lateral-torsional buckling capacity of mild steel castellated beam with sinusoidal web openings

This paper examines the lateral-torsional buckling behaviour of mild steel castellated beams with sinusoidal perforations. A non-linear finite element model has been developed, considering geometrical imperfections and material nonlinearities. The results of the finite element analysis, such as failure load, failure displacement, load–displacement curve, and type of failure of the castellated steel beams, were verified experimentally. The finite element model was developed to examine the impact of the length of the castellated beam, flange slenderness, and web slenderness on the ultimate buckling load of castellated steel beams. The results show that using a less slender web and flange increases the load-carrying capacity of castellated beams with sinusoidal web openings. Furthermore, it was observed that short-span beams exhibit greater resistance to lateral-torsional buckling compared to long-span beams. © The Author(s), under exclusive licence to Springer Nature Switzerland AG 2024.