Numerical Study of Performance of Alternate Closed Opening Castellated Beam Using Double Steel Channel Shapes

This numerical study presented and analysed a new technic of castellated steel beam "Alternate Closed Opening Castellated Beam" applied only to double steel channel shapes connected back to back.ABAQUS/2019 program employed to create modelling and analysis for two groups of models with the same length and conditions of loading.The first group has three noncomposite beam models: the first reference model without castellated, the second model with normal castellated and the third model with new castellated, also the second group has three composite beam models: the first reference model without castellated, second model with normal castellated and the third model with the new castellated.According to the analysis results; For the first noncompsite group, ultimate load for the second and third models increased by 8.84% and 16.63%, respectively, compared to the reference model, with local buckling in the top flanges under concentrated loads and lateral-torsional buckling as the failure modes.For the second composite group, the ultimate load for the second and third models increased by 41.83% and 62.19%, respectively, compared to the first reference model, with the flexural mechanism as the main failure mode.This enhancement in the load-carrying capacities of the new Alternate Closed Opening Castellated Beams is due to the limit states mode of failures resulting from web holes.