Stability of Steel Columns with Non-Uniform Cross-Sections

Abstract

Abstract:In this work, non-uniform steel members with or without initial geometrical or loading imperfections, that are loaded by axial forces applied concentrically or eccentrically and by concentrated moments applied at the ends or at intermediate points, are studied. More specifically, steel members with varying cross-sections, tapered or stepped or members consisting by two different tapered parts are considered. The formulation presented in this work is based on solving the governing equation of the problem through a numerical method where the eigenshapes of the member are employed. A failure plasticity criterion is introduced for members especially the short ones that will never reach the elastic critical buckling load. Although only the simply supported beam-column case is studied herein, it is obvious that the method can be extended to multi-span beams and frames, by employing the corresponding eigenshapes. Useful diagrams are presented for both the critical buckling loads and the equilibrium paths showing the influence of the main characteristics of the beam-column.

Stability Analysis of Steel Columns with Fixed-Free Ends under Axial Compression: Uniform and Non-Uniform Square Hollow Sections

“…In engineering structures, there are columns with non-uniform cross-sections where there may be different holes for different applications. The use of steel columns with non-uniform cross-sections is very common [22]. This type of geometry makes structural elements more unstable under buckling.…”

“…This type of geometry makes structural elements more unstable under buckling. [22] present a method for the study of non-uniform steel members with or without imperfections, where the governing equation of the problem is solved by the Galerkin method using the eigen shapes of the member. In its research, he proves the accuracy of its method using different cross-sections from IPE and HEB profiles.…”

Buckling analysis of nanobeams with exponentially varying stiffness by differential quadrature method

“…On the other hand, the previous studies present investigations on the variable cross section in case of beams [43,44] and a few in case of nanostructures. [45] In case of buckling analysis of beams, the previous authors have used various ways of nonuniform cross section.…”

Stability of non-prismatic frames with flexible connections and elastic supports

“…Valipour and Bradford (2012) used the forcebased approach for obtaining a new shape function for tapered three-dimensional beams with flexible connections. The stability of steel columns with non-uniform cross-section studied by Konstantakopoulos et al (2012) based on the Galerkin technique. More recently, Taha and Essam (2013) investigated stability behavior and free vibration of tapered columns with elastic end restraints by using the DQM method.…”