Location

Saint Louis, Missouri

Session Dates

20 Oct 1992

Abstract

Current North American guidelines for the design of cold-formed steel members consider the web of cold-formed steel sections under direct compression to be a fully stiffened element. This, however, may not be true if the flanges cannot provide sufficient restraint to the web. In this case, instability of the web element may cause distortional failure of the flange-edge stiffener component which may limit the load-carrying capacity of these sections with very little post-buckling strength being realized. In the present paper, the effect of web buckling on the load-carrying capacity of Z-sections with partially stiffened flanges is examined. The current design criteria for cold-formed steel sections with edge stiffeners located perpendicular to the flanges are reviewed and evaluated through comparison with experimental data obtained in a test program involving 85 Z-sections loaded in direct compression with pin-ended condition. The Z-sections varied in length from 18 in. (459 mm) to 48 in. (1219 mm). The important parametric variations in these tests were the width-to-thickness ratio of the flanges, and the width of the edge stiffeners. Based on the results from this study, a procedure for predicting the load-carrying capacity of coldformed steel Z-sections subject to local buckling of the web under direct compression was developed.

Department(s)

Civil, Architectural and Environmental Engineering

Research Center/Lab(s)

Wei-Wen Yu Center for Cold-Formed Steel Structures

Meeting Name

11th International Specialty Conference on Cold-Formed Steel Structures

Publisher

University of Missouri--Rolla

Document Version

Final Version

Rights

© 1992 University of Missouri--Rolla, All rights reserved.

Document Type

Article - Conference proceedings

File Type

text

Language

English

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Oct 20th, 12:00 AM

Distortional Buckling of Cold-formed Steel Z-section Columns

Saint Louis, Missouri

Current North American guidelines for the design of cold-formed steel members consider the web of cold-formed steel sections under direct compression to be a fully stiffened element. This, however, may not be true if the flanges cannot provide sufficient restraint to the web. In this case, instability of the web element may cause distortional failure of the flange-edge stiffener component which may limit the load-carrying capacity of these sections with very little post-buckling strength being realized. In the present paper, the effect of web buckling on the load-carrying capacity of Z-sections with partially stiffened flanges is examined. The current design criteria for cold-formed steel sections with edge stiffeners located perpendicular to the flanges are reviewed and evaluated through comparison with experimental data obtained in a test program involving 85 Z-sections loaded in direct compression with pin-ended condition. The Z-sections varied in length from 18 in. (459 mm) to 48 in. (1219 mm). The important parametric variations in these tests were the width-to-thickness ratio of the flanges, and the width of the edge stiffeners. Based on the results from this study, a procedure for predicting the load-carrying capacity of coldformed steel Z-sections subject to local buckling of the web under direct compression was developed.