Ultimate Strength of Geometrically Imperfect Angle Columns

摘要

The paper investigates the influence of initial out-of-straightness on theultimate strength of angle columns. A general unequal angle section has no axis of symmetry. As such, the ultimate angle column behavior is not only dependent on the magnitude but also the orientation of the initial out-of-straightness in the compression member. A numerical incremental-iterative procedure for tracing the nonlinear load-deflection path based on the updated Lagrangian formulation accounting for the effect of partial yielding is presented. The method has been used to predict experimental results obtained by Kitipornchai and Lee (1986b), and to study the sensitivity of the ultimate strength of angle columns to the magnitude and the orientation of the initial out-of-straightness.