Eccentrically loaded high strength concrete-filled square steel tubes

摘要

This paper presents test results for 8 high strength concrete-filled square steel tubes subjected to eccentric compression. The column section size was 150 x 150 mm. The primary parameters were slenderness ratios, varying from 25.4 to 71.6, steel ratios, between 8.2% and 14.4%, eccentric distance, 20mm and 40mm. The average strength of the concrete cubes at the time of the columns testing was 94.1 N/mm~2. At the same time, a numerical analysis procedure was proposed. The model of the stress-strain of the steel and the core concrete, which were separated from the experiments on axially compressive short columns, were used in the procedure, and two-way stress in the steel plate was considered. The numerical analysis results agreed well with the experimental results. Furthermore, the influence of the factors, such as slenderness ratio, eccentric ratio, steel ratio, concrete strength and steel strength on the eccentrically loaded columns were discussed.