High strength thin-walled rectangular concrete-filled steel tubular slender beam-columns, Part I: modeling

Authors

Vipulkumar Ishvarbhai Patel, Victoria University, Melbourne
Qing Quan Liang
Muhammad N. S Hadi, University of WollongongFollow

RIS ID

46690

Publication Details

Patel, V. Ishvarbhai., Liang, Q. Quan. Hadi, M. N.S. (2012). High strength thin-walled rectangular concrete-filled steel tubular slender beam-columns, Part I: modeling. Journal of Constructional Steel Research, 70 (N/A), 377-384.

Abstract

High strength thin-walled rectangular concrete-filled steel tubular (CFST) slender beam-columns under eccentric loading may undergo local and overall buckling. The modeling of the interaction between local and overall buckling is highly complicated. There is relatively little numerical study on the interaction buckling of high strength thin-walled rectangular CFST slender beam-columns. This paper presents a new numerical model for simulating the nonlinear inelastic behavior of uniaxially loaded high strength thin-walled rectangular CFST slender beam-columns with local buckling effects. The cross-section strengths of CFST beam-columns are modeled using the fiber element method. The progressive local and post-local buckling of thin steel tube walls under stress gradients is simulated by gradually redistributing normal stresses within the steel tube walls. New efficient Müller's method algorithms are developed to iterate the neutral axis depth in the cross-sectional analysis and to adjust the curvature at the columns ends in the axial load–moment interaction strength analysis of a slender beam-column to satisfy equilibrium conditions. Analysis procedures for determining the load–deflection and axial load–moment interaction curves for high strength thin-walled rectangular CFST slender beam-columns incorporating progressive local bucking and initial geometric imperfections are presented. The new numerical model developed is shown to be efficient for predicting axial load–deflection and axial load–moment interaction curves for high strength thin-walled rectangular CFST slender beam-columns. The verification of the numerical model and parametric studies is given in a companion paper.