Experimental Behavior and Design of High-Strength Circular Concrete-Filled Steel Tube Short Columns: Fid-Bau Portal

Experimental Behavior and Design of High-Strength Circular Concrete-Filled Steel Tube Short Columns

Wei, Jiangang / Luo, Xia / Lai, Zhichao / Varma, Amit H.

This paper investigates the behavior of high-strength circular concrete-filled steel tube (CFST) short columns. An experimental database consisting of 87 tests conducted on high-strength circular CFST short columns was compiled, and gaps in the existing research were identified. A total of 20 tests were then conducted to address the gaps in the database. The test parameters were the diameter-to-thickness ratio of the steel tubes $D / t$ , the yield stress of steel $F_{y}$ , and the compressive strength of concrete $f_{c}^{'}$ . The tests indicated that the strength of high-strength circular CFST short columns increases with increasing $F_{y}$ and $f_{c}^{'}$ , but decreases with increasing $D / t$ . All tested high-strength circular CFST short columns had acceptable ductility. Four of the specimens did not have any strength degradation, while the other 16 specimens retained at least 70% of their strength at strains of 5%. Results from the tests conducted in this research were combined with those from the compiled database; the combined results were used to evaluate the applicability of current design equations for estimating the cross-sectional strength of high-strength circular CFST columns. The evaluations indicated that the Japanese code provides the most accurate estimation.