Behavior of steel beam to circular CFT column connections

This paper describes the structural behavior of connections between concrete-filled tubular (CFT) steel column and steel beam. The connections are characterized with the flange plates penetrated through the column. Four beam-to-column subassemblage specimens were tested under reversal loading. Specimens with strong shear capacity in the panel zone demonstrated stable hysteresis behavior by forming the plastic hinge in the beam. Specimen having panel zone shear yielding resulted in pinching hysteresis curve, which was caused by the diagonal shear cracking of the concrete inside the steel tube. The shear capacity of the CFT column in the panel zone is contributed from the steel tube and concrete core and can be estimated by superposition of the strengths of the steel tube and the concrete.