Seismic performance of joint between L-shaped CFST column and H-section beam with lower plate and extended flange plate

Bolted joints are widely used in beam-to-column joints in structures due to the advantages of fast construction, convenient installation and disassembly, and resource conservation. A bolted joint configuration between L-shaped concrete-filled steel tubular column and H-section beam with lower plate and extended flange plate was proposed, realizing fully-bolted connections between the upper and lower columns, as well as between the beam and the column. Four specimens, with different bolt numbers on the beam flange or different configurations of stiffeners, had been designed and tested under cyclic loads. Finite element models were developed and validated based on the test results, and parametric analysis was performed to analyze the influence of extended flange plate thickness on the mechanical properties of the joints. According to the results, the hysteresis curves of the specimens were plump, and the slippages between the extended flange plate and the beam flange improved the ductility and energy dissipation capacity of the specimens. Increasing bolt number on the beam flange signifi-cantly increased the joint resistance and stiffness. The beam vertical stiffeners limited the development of the plastic deformation of the beam flange, thereby reducing the local buckling of the beam section. Based on the experimental and finite element analysis results, simplified calculation formulas and design procedures for the joint are proposed.