Experimental study of steel I-beam to CFT column connections

This paper focused on the experimental study of the composite behavior of steel universal beam to concrete-filled tube (CFT) column connections. Eight specimens were designed and tested to failure, of which four specimens are simple beam-column connections and the rest are rigid connections with different type of stiffening details. For simple connections, the parameters investigated are the thickness and diameter of the steel tube and the beam size. For the rigid connections, the stiffening details investigated include cover plate, shear plate, external ring and re-bar respectively. Experimental results showed that the simple connections have weaker ultimate strength, ductility and stiffness, and their behaviors are influenced by the parameters investigated. All stiffening details improved the composite behavior, but to different extent. The specimen with the re-bar detail that is easy to fabricate and costs effective exhibited excellent behavior in terms of ultimate strength, stiffness and ductility.