Inelastic Amplification Factor for Design of Steel Beam‐Columns
Publication: Journal of Structural Engineering
Volume 118, Issue 7
Abstract
The present design interaction equations for steel beam‐columns subjected to end moments and axial loads employ a simplified form of elastic moment amplification factor. This amplification factor is conservative for some values of axial load and unconservative for other values. To accurately represent the amplification factor over a wide range of axial loads, a refined expression for elastic amplification was proposed in the previous literature. This elastic amplification factor provides a good estimation of the amplified moment only for members with very high slenderness ratios that fail by elastic buckling. Members with intermediate slenderness ratios, particularly those with high shape factor, will fail by inelastic buckling, and this inelasticity will have a major influence on the strength of these members. To accurately include the effects of inelasticity in the design interaction equations, this paper develops expressions for an inelastic amplification factor (IAF). The IAF expressions are developed using numerical results obtained by carrying out inelastic analysis of beam‐columns with various shape factors, slenderness ratios, and end moments. Design interaction equations with the load and resistance factor design (LRFD) ‐factor and the IAF are compared with numerical inelastic strength of beam‐columns.
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Information & Authors
Information
Published In
Journal of Structural Engineering
Volume 118 • Issue 7 • July 1992
Pages: 1822 - 1839
Copyright
Copyright © 1992 ASCE.
History
Published online: Jul 1, 1992
Published in print: Jul 1992
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