Analyzing Effective Length Factor of OBS Members


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Using OBS (Off-center Bracing System) is one of the methods to make buildings resistant to the lateral Loads. This kind of brace has a great tendency to out of plane buckling. So, due to the lack of formal regulations, analyzing out of plane effective length of its members is important. In this paper, buckling load of 15 one-story frames is obtained and then out of plane effective length factor of the longer member is calculated. Finally, as buckling of one of the members causes the system to lose its stability, the mentioned effective length factor is introduced as out of plane effective length factor for all OBS members.



Advanced Materials Research (Volumes 255-260)

Edited by:

Jingying Zhao




A. Naderi and M. R. Sohrabi, "Analyzing Effective Length Factor of OBS Members", Advanced Materials Research, Vols. 255-260, pp. 40-44, 2011

Online since:

May 2011




[1] R. D. Cook. D. S. Malkus and M. E. Plesha: Concepts and Applications of Finite Element Analysis, Third Edition, John Wiley & Sons, Inc, ISBN 0-471-84788-7, (1989).

[2] H.A. Moghaddam and H. E. Estekanchi: Seismic Behavior of Off-Centre Bracing Systems, Journal of Constructional Steel Research, v51, n2, pp.177-196, (1999).


[3] H. Saffari and H.A. Mosalman yazdi: Determine of Buckling Load of OBS, First national congress of civil engineering, (2004).

[4] H.A. Moghaddam and H.E. Estekanchi: On the Characteristics of an Off-Centre Bracing System, Journal of Constructional Steel Research, v35, pp.361-376, (1995).


[5] J. Salejegheh: Theory of Elasticity and Plasticity, Shahid Bahonar University of Kerman Publication, First Edition, (2005).

[6] D. Hanselman and B. Littlefield: Mastering MATLAB 7, ISBN 978-964-327-061-2.