Inelastic bifurcation analysis of locally buckled channel columns

摘要

The paper describes an inelastic bifurcation analysis of locally buckled columns. The members are assumed to be geometrically perfect in the overall sense but could include geometric imperfections and yielding in the local mode. The method of analysis uses an inelastic geometric non-linear finite strip local buckling analysis to determine the tangent rigidities of the locally buckled section. These tangent rigidities are substituted into the flexural and flexural-torsional equations to calculate the inelastic overall bifurcation loads. The bifurcation analysis is applied in the present paper to plain channel columns and compared with tests on fixed-ended cold-formed columns. The bifurcation loads are in good agreement with the test strengths. In addition, the effect of yielding is highlighted in this paper.