Nonlinear Finite Element Analysis on Loading Transfer Mechanism of Joints in Concrete Filled Tubular Column Frames

摘要

Frame joints are the key points of Concrete Filled Steel Tubular (CFST) column -steel beam connection. They act as propagating internal force, distributing internal force and undertaking integrity in the frame structure. Based on the appropriate material constitutive equation and failure criterion, the finite element analysis of the joints in CFST column frame was carried out with ANSYS. Analysis results show that the concrete compression stresses along diagonal line in the core area of the intermediate joint present the evident central line, and become the diagonal compression member. The more is the axial compression ratio in the column, the more are the compression stress and compression strain in the diagonal compression member.