Seismic Analysis of Asymmetric Buildings with Flexible Floor Diaphragms
Publication: Journal of Structural Engineering
Volume 130, Issue 8
Abstract
Even though a rigid floor diaphragm is a good assumption for seismic analysis of most buildings, several building configurations may exhibit significant flexibility in floor diaphragm. However, the issue of static seismic analysis of such buildings for torsional provisions of codes has not been addressed in the literature. Besides, the concept of center of rigidity needs to be formulated for buildings with flexible floor diaphragms. In this paper, the definition of center of rigidity for rigid floor diaphragm buildings has been extended to unsymmetrical buildings with flexible floors. A superposition-based analysis procedure is proposed to implement code-specified torsional provisions for buildings with flexible floor diaphragms. The procedure suggested considers amplification of static eccentricity as well as accidental eccentricity. The proposed approach is applicable to orthogonal as well as nonorthogonal unsymmetrical buildings and accounts for all possible definitions of center of rigidity.
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Information & Authors
Information
Published In
Journal of Structural Engineering
Volume 130 • Issue 8 • August 2004
Pages: 1169 - 1176
Copyright
Copyright © 2004 American Society of Civil Engineers.
History
Received: Apr 19, 2000
Accepted: Jul 29, 2003
Published online: Jul 15, 2004
Published in print: Aug 2004
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