Comparative Study of Plain Steel Profile Composite Column and Castellated Steel Profile Composite Column

Abstract

This study investigates the axial and flexural behavior of castellated steel-concrete composite columns for application in high-rise buildings subjected to seismic loads. While steel columns offer high strength with relative light weight, their high cost remains a limitation. Castellated profiles present a potential solution due to their increased structural efficiency and reduced weight, but are rarely used in columns due to buckling concerns. To overcome this, castellated profiles were modified into a king cross shape to eliminate weak axis behavior. A 10-story school building was modeled using ETABS v22 based on SNI 1726:2019, SNI 7860:2020, and SNI 1729:2020 which adopt provisions similar to ASCE 7-16, AISC 341-16, and AISC 360-16. Structural performance and material cost efficiency were analyzed for both plain and castellated profiles, in steel and composite configurations. The results indicate that castellated steel columns improve axial capacity by 17% and flexural capacity by 52%. When used as composite columns, they further increase flexural strength by 43% and reduce material cost by 26% compared to plain profiles. These findings demonstrate that castellated composite columns are a viable and cost-effective alternative for seismic-resistant high-rise construction.