Ultimate Load of Cellular Beams Subjected to Web Posts Buckling

Steel cellular beams are widely used in multi‑story buildings for long spans and service integration, reducing overall height. However, their openings may cause local instability, notably web‑post buckling.This paper presents a simplified analytical approach to predict the ultimate load causing the web‑post buckling under longitudinal shear in simply‑supported symmetric steel cellular beams with transverse stiffeners. The method incorporates a reduction factor that accounts for the number of openings, configuring the influence of the web posts assumed to be affected by buckling. The results were validated through experimental data from the literature and verified using numerical simulations with Cast3M software.