Journal of Constructional Steel Research, cilt.214, 2024 (SCI-Expanded)
To date, many studies have been conducted on the experimental behaviors of circular and square hollow section braces. In those studies, the effect of material properties, cross-sectional shape and loading history on the performance of braces were investigated independently of each other. In this study, the effects of the combined actions of these variables on the performance of steel braces were examined. For this purpose, approximately 1/3 scaled 12 specimens (6 circular and 6 square), which were cold formed from carbon/stainless steel sheets, were experimentally and numerically investigated under 3 different cyclic load effects representing far field and near fault loadings. The buckling strength, energy dissipation capacity and displacement ductility of the specimens were evaluated. In addition, parametric studies, using 198 FE analyses verified with current study, were conducted. Experimental results indicate that the buckling strength limits provided in AISC 360–22 and EN 1993-1-1 for carbon steel braces are significantly influenced by the cross-section, loading protocol and material properties. On the other hand, it has been determined that the buckling strength limits given in AISC 370–21 and EN 1993-1-4 for stainless steel braces are safe for far field loadings, but insufficient for near fault loadings along the full slenderness range. It has been seen that the most disadvantageous results for the buckling strength, energy dissipation capacity and displacement ductility of the braces can only be obtained by applying different loading protocols. Moreover, It has been determined that the effect of material properties on the performance of braces varies considerably depending on the cross-section geometry.