Research of high strength concrete-filled square steel tubular short columns subjected to eccentric compression

This paper presents an experimental research of 8 high strength concrete-filled square steel tubular columns(CFSST)subjected to eccentric compression.The analysis suggests positive effect of eccentric ratio and concrete strength on the behavior of CFSST columns under eccentric compression.The results indicate that the CFSST columns subjected to eccentric load have preferable performance of elasticity and plasticity.Both eccentricity ratio and concrete strength would affect the ultimate load,but the effect of eccentric ratio is more significant.With the increase of eccentric ratio,the effect of confinement force enhancing concrete strength as well as the ultimate load of CFSST columns will decrease.The increment of eccentric ratio is nonlinear with the decrease of ultimate load.The influence of concrete strength on the ultimate load relates to eccentric ratio,when eccentric ratio is below 0.5,the increase of concrete strength will improve the ultimate load greatly;and when eccentric ratio is above 0.5,the influence of concrete strength on ultimate load is small.