Static behavior of T-shaped concrete-filled steel tubular columns subjected to eccentric compressive loads

Special-shaped column frame structures improve residential architectural space, by eliminating the exposure of column corners to indoor space. Due to improvement in constraint effect for concrete, special-shaped Concrete-Filled Steel Tubular (CFST) columns are expected to have advantages in mechanical behavior. In the meanwhile, steel plates' premature local buckling and concave corner's separation between steel tube and concrete should be given more attention. The tensile bar stiffener, welded on inside tube surfaces, was introduced in this paper. Experimental study of 4 T-shaped columns subjected to eccentric compressive loads was carried out. Parametric impact analysis was emphasized on the constraint effect, the eccentricity and the specimen type. Failure modes and static mechanical properties were investigated. Experimental results showed that: the tensile bar stiffener effectively restrains the deformation at welds of steel plates and concave corners; the CFST specimens are provided with better comprehensive mechanical performance, especially for the stiffened CFST specimens.