Influence of local postbuckling behaviour on bending of thin-walled beams

• Published in: Thin-walled structures Vol. 25; no. 3; pp. 219 - 230
• Main Authors: Manevich, Arkady, Kolakowski, Zbigniew
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01.07.1996; New York, NY Elsevier Science
• Subjects: Buckling; Exact sciences and technology; Fundamental areas of phenomenology (including applications); Physics; Solid mechanics; Static buckling and instability; Structural and continuum mechanics; Bending moment; Beam column structure; Loadbearing capacity; Numerical method; Axial load; Thin walled beam; Non linear effect; Postbuckling
• ISSN: 0263-8231; 1879-3223
• DOI: 10.1016/0263-8231(95)00053-4

The influence of the local postbuckling behaviour on the bending of thinwalled beams is studied. The analysis of the postbuckling behaviour of a prismatic column-beam subject to compression and bending is employed in order to determine the overall flexural stiffness of a beam after local buckling. The asymptotic Koiter method is used in the second order approximation. The determination of post-buckling coefficients enables one to find the beam's flexural stiffness without the necessity of using hypotheses on effective widths of eccentrically compressed plates. It is shown that the post-buckling equilibrium branch in a bending moment-global curvature coordinate system for a perfectly elastic thin-walled beam is rectilinear (in the second order approximation of' the asymptotic method). Simple analytical relations are presented between the slope of the post-buckling equilibrium branch of global bending and post-buckling coefficients for local buckling mode. The results obtained are compared with data reported by other authors.