Postbuckling of One-Dimensional Elements with Thin-Walled Angle Section Using Simplified Models*

Abstract

ABSTRACT The present work is a detailed study of the initial post-critical behavior of one-dimensional elements with an angle section, using simplified models. The emphasis of the work is on the influence that the deformation of the cross section has on the critical and post-critical states. The model assumes that the cross section deforms entirely by rotation of the legs about the hinge at the apex. Three structural types are considered: the column under an axial load, the circular arch under a central load, and the circular ring under uniform radial pressure Critical states are assumed to be distinct, in the sense that mode interaction effects may be neglected. The critical states for all cases analyzed are unaffected by angle deformation, while the post-critical states are affected to different degrees, depending on the structural configurations. A parameter that defines post-critical strength has been consistently defined for the cases of the column and the arch. The unstable post-critical behavior found for short angle columns makes this type of structure sensitive to imperfections.