Tapered Box Columns under Biaxial Loading

Abstract

The stability of symmetric pin‐ended square box column tapering from the mid‐length to the ends and subjected to the combined action of axial thrust and biaxial moments is investigated. Torsional‐flexural behavior is not considered. The tangent stiffness method is used to develop the moment‐curvature‐thrust relationships for the column cross section. The stability problem is transformed into a nonlinear programming problem and the ultimate load‐carrying capacity of the member is defined by extending Home's stability criterion. Due allowance is made to account for the effect of residual stresses and column initial deflections. Columns having positive and negative taper slopes are considered. The results are presented in the form of interaction diagrams.