Equivalent Uniform Moment Diagram Factor for Composite Columns in Major Axis Bending
Publication: Journal of Structural Engineering
Volume 131, Issue 4
Abstract
The ACI Building Code permits the use of the equivalent uniform bending moment diagram factor for computing the effect of moment gradient, along the column height, caused by unequal column end moments. The concept of equivalent uniform moment diagram was introduced into design practice to eliminate the need for extensive calculations based on the solution to a differential equation. The expression currently used by the ACI Building Code is a simplified equation based on the elastic behavior of columns, and does not include the inelastic material behavior. This study was conducted to investigate the influence of different variables on of slender, tied, rectangular composite columns in which steel shapes are encased in concrete and to examine existing expressions for . Approximately, 11,000 square composite columns, each with a different combination of specified values of variables, were simulated. The columns studied were subjected to short-term ultimate loads and unequal end moments causing moment gradient in single curvature and double curvature bending about the major axis of the encased steel section. Two design equations are proposed in this paper.
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Information & Authors
Information
Published In
Journal of Structural Engineering
Volume 131 • Issue 4 • April 2005
Pages: 569 - 581
Copyright
© 2005 ASCE.
History
Received: Aug 4, 2003
Accepted: Jun 10, 2004
Published online: Apr 1, 2005
Published in print: Apr 2005
Notes
Note. Associate Editor: Jose I. Restrepo
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