With an increasing trend towards the use of higher strength materials, members in steel structures become more slender. The cross-sectional plate elements of such members also become slender, triggering possible interaction between local buckling of the flange and web elements and the overall buckling of the column. The paper proposes use of plate buckling response, in terms of in-plane load and axial deformation, as modified stress-strain curves for use in column analysis. These curves can be derived from numerical analysis of such plates or may be based on experiments, where available. When the rigorous analysis of such columns is carried out using numerical techniques such as the finite difference method, rapid solutions are obtained for an otherwise very complex problem. The paper includes a parametric study aimed at examining the design of stiffened plate elements such as those used in box-girders.
Local and Global Buckling; Stiffened Plates; Ultimate strength