Numerical study on the performance of beam-to-concrete-filled steel tube column joint with adapter-bracket:

An innovative beam-to-column composite joint with adapter-bracket was proposed and its behavior was investigated through finite element analysis. The special adapter-bracket is to facilitate the assembly of the steel box beam and the concrete-filled steel tube column through high-strength blind bolts. In the adapter-bracket, two endplates are welded to the beam and bolted to the column, respectively. First, two finite element models of the bolted extended endplate joint were developed in ABAQUS and validated by available experimental results. Then, based on modified models, parametric analyses were conducted to evaluate the novel joint performance, in terms of the initial stiffness, rotation capacity, moment capacity, failure mode, and joint classification. The variables included flange thickness, endplate thickness, and bolt size. Results demonstrated that the joint behavior was significantly affected by the flange thickness, the endplate-A thickness, and bolt size while slightly influenced by the endplate-B thickness. Additionally, these joints had favorable rotation and moment capacity.