The construction industry is facing increasing pressure to reduce the embodied carbon, particularly in structural steel systems, which contributes significantly to the global Greenhouse Gas (GHG) emissions. As a potential solution, castellated beams offer enhanced structural efficiency through web openings that increase stiffness while reducing the material usage. This study investigated the application of castellated beams as secondary structural members and evaluated their Embodied Carbon (EC) performance in comparison with that of conventional I-beams. A simply supported beam with a 12 m span was analyzed under typical floor loads. The structural performance was assessed based on the strength and deflection criteria using the American Institute of Steel Construction (AISC) design provisions, whereas the EC was calculated using a cradle-to-gate approach. The results demonstrate that the castellated beam (CB18×14) meets all the structural requirements and exhibits superior deflection performance compared to the conventional W14×22 I-beam. Moreover, the castellated beam achieved a 27% reduction in EC per linear foot, highlighting its potential as a sustainable alternative to steel-framed buildings. These findings emphasize the dual benefits of castellated beams in enhancing the structural performance and reducing the environmental impact in secondary beam applications.
Suwondo et al. (Mon,) studied this question.