Abstract: The concrete-filled double skin steel tube (CFDST) is a unique steel-concrete composite construction that consists of two steel layers with a concrete layer in between. The inner hollow steel section serves as formwork and concrete reinforcement. Concrete prevents local buckling in hollow steel sections, increasing the section's ductility. CFDST has a number of benefits, including high strength, bending stiffness, and earthquake and fire resistance. Because of the large confinement effect, the circular CFDST column outperforms all other shapes for all parameters. Among all the literatures present, they have not studied the response to combine axial loading, moments and torsion, in this paper a building located at Vallabh Vidyanagar city was selected as the study frame and RCC column of that frame was taken as economical for given loadings. All the columns of this study frame were then replaced by equivalent CFDST columns and then by CFST columns (both circular sections) based on FE analysis results after analysing both the section in ABAQUS software. Performance evaluation of all three frames then carried out and compared. From that we can say that the forces which were present in thee RCC or CFST section were reduced by significant amount which says that CFDST column’s performance is better than both RCC and CFST columns under static loadings. The seismic performance of CFDST column section was found better than RCC frame or CFST frame under four different time-history analysis with that we can say that CFDST column can be used as an improvement over RCC or CFST column section.

Keywords: Circular Column, Composite Columns, Concrete-filled double skin steel tubes (CFDST), Comparative Study, Finite element analysis

| DOI: 10.17148/IARJSET.2022.9590