Nonlinear inelastic analysis of concrete-filled steel tubular frames

Abstract

This paper presents a reliable numerical procedure for the nonlinear inelastic analysis of concrete-filled steel tubular frames. Geometric nonlinearities are taken into account by the use of stability functions derived from the exact stability solution of a beam-column subjected to axial force and bending moments. The spread of plasticity over the cross section and along the member length is captured by tracing the uniaxial stress-strain relationships of each fiber on the cross sections located at the selected integration points along the member length. The nonlinear equilibrium equations are solved using an incremental-iterative scheme based on the generalized displacement control method be..