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http://dx.doi.org/10.12989/sem.2006.22.6.685

Effective length factor for columns in braced frames considering axial forces on restraining members  

Mahini, M.R. (Civil Engineering Group, Persian Gulf University)
Seyyedian, H. (Civil Engineering Department, Shiraz University)
Publication Information
Structural Engineering and Mechanics / v.22, no.6, 2006 , pp. 685-700 More about this Journal
Abstract
The effective length factor is a familiar concept for practicing engineers and has long been an approach for column stability evaluations. Neglecting the effects of axial force in the restraining members, in the case of sway prevented frames, is one of the simplifying assumptions which the Alignment Charts, the conventional nomographs for K-Factor determination, are based on. A survey on the problem reveals that the K-Factor of the columns may be significantly affected when the differences in axial forces are taken into account. In this paper a new iterative approach, with high convergence rate, based on the general principles of structural mechanics is developed and the patterns for detection of the critical member are presented and discussed in details. Such facilities are not available in the previously presented methods. A constructive methodology is outlined and the usefulness of the proposed algorithm is illustrated by numerical examples.
Keywords
effective length factor; K-factor; frame stability; column buckling; braced frame;
Citations & Related Records

Times Cited By Web Of Science : 5  (Related Records In Web of Science)
Times Cited By SCOPUS : 5
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