Experimental study on steel-reinforced concrete-filled steel tubular columns under the fire

This paper aims to experimentally study the fire performance of steel-reinforced concrete-filled steel tubular (SRCFST) columns without protection. Eight SRCFST specimens with cruciform section profiled were tested under ISO-834 standard fire. The various test parameters including cross-section type tube (circular or square), load ratio and eccentricity considered discussed. temperature distribution, failure modes, axial lateral deformation, resistance obtained by investigated in detail. results show that provided great confinement effect core concrete, can efficiently suppress generation development cracks concrete. diverse loading method present tendency deformation versus time curves, i.e. five stages for axially common (n = 0.4) three high > eccentric compression. critical is much lower than structures CFST at same parameters, has significant improvement compared columns. Moreover, available design evaluate applicability specimens.