Seismic performance of CFST column to steel beam joint with RC slab: Joint model

Abstract Based on the previous experimental and numerical investigations presented in Han and Li (2010)and Li and Han (2011), this paper studies the joint model for the composite joint consisted of circular concrete filled steel tubular (CFST) column and steel beam with external diaphragm. The elastic shear stiffness and the shear deformation of the joint panel zone are investigated by parametric study using the finite element analysis (FEA) model. A hysteretic model incorporating the shear stiffness, shear strength, shear deformation and the hysteretic rules is proposed for the panel zone of the composite joint. This hysteretic model is then integrated in a fiber-based joint macro element. The joint macro element is validated by both FEA and experimental results. The overall and the local behavior of CFST joints and frame with macro elements are investigated. The proposed model is featured with a favorable accuracy and amenable modeling method, and could be applied to simulate the seismic behavior of large-scale and complex composite structural systems.