ABSTRACT
This paper summarizes experimental results of an innovative concrete filled steel tubular (CFT) column system, named as confined CFT or CCFT, for improved seismic design of steel and concrete composite structures. Based on fundamental mechanics, the design concept is aimed at controlling the local buckling of the steel tube and confining the concrete in the potential plastic hinge regions of a CFT column. All the specimens tested can be considered as full-scale to two-third scale models of the structural components generally used in practice. The results showed that composite columns had very high ductility and capacity of energy absorption because of the interaction between the steel tube, concrete and the additional transverse confinement. Experimental tests validated the concept of the CCFT. As demonstrated from the results of seismic loading tests, the new type of CFT column system can provide excellent seismic performance.
