Study on Mechanical Properties of Partially Concrete-encased Cold-formed Thin-walled C-section Steel Compression-bending Members

Abstract Cold-formed thin-walled C-section steel is prone to localized strength deficiencies. To address this issue, partially encased concrete (PEC) columns have been integrated into the steel to form partially encased concrete cold-formed thin-walled c-section steel compression-bending members. In this study, a finite element model of 36 PEC composite columns is developed using ABAQUS finite element software. The impact of various factors, including PEC column section size, eccentric distance, batten plate spacing, and concrete strength, on the eccentric compression behavior of these members is investigated. The results of the analysis show that both the ultimate bearing capacity and initial stiffness of PEC columns increase with the section size, while they decrease with the increase in eccentric distance. The batten plate spacing has minimal effect on the ultimate bearing capacity and initial stiffness of PEC columns under eccentric compression. Additionally, concrete strength plays a role in the ultimate bearing capacity of PEC columns, with higher concrete strength leading to a higher ultimate bearing capacity.