Experimental evaluation of composite beam-to-column joint using cold-formed steel sections

Abstract

This paper is focusing on the experimental investigation of composite beam-to-column joint formed by a composite concrete slab and two lipped cold-formed steel C-sections placed back-to-back as beam and column. As the bare joint of cold-formed sections might not have higher moment resistant, a composite action from the composite concrete slab is utilized and expected to enhance the load carrying capacity of the joint. Two specimens namely the composite joint and non-composite joint are constructed and tested until failure under a point load at a certain eccentricity from the face of the column to induce moment to the joint. All components which are the decking, hot rolled plate, bolts and reinforcement bar used were the same for both specimens except the arrangement of the longitudinal bars. The relationship between the load and deflection, and subsequently, the moment and rotation of the joints are obtained specifically, the ultimate load and the respective moment resistance. It is found out that the composite joint yields higher ultimate load and moment resistance compare to the non-composite joint. The results also indicate that a composite joint has credible rotation and moment resistance, and the fracture of the joint occurs after substantial rotational deformation has been achieved.