Inelastic Cyclic Analysis of Imperfect Columns

Abstract

The hysteretic behavior of a simply supported prismatic steel column with initial out‐of‐straightness subjected to cyclic loading is presented. The analysis is based on the plastic hinge concept, which under the assumption of perfect plasticity together with the one‐dimensional idealization of the column, has led to an elegant closed form solution for any history of axial loading. The exact yield curve of any type of cross‐sectional shape is adequately approximated by a piecewise linear interpolation of the fully plastic states in pure bending and in pure tension and compression. The results presented here illustrate the imperfection sensitivity of column cyclic behavior. The effect of various slenderness ratios combined with different initial imperfection sizes as well as the effect of different approximation to the exact yield curve are also presented.