Stiffness Reduction Factor for Flat Slab Structures under Lateral Loads
Publication: Journal of Structural Engineering
Volume 135, Issue 6
Abstract
Effective beam width model (EBWM) has been widely used for predicting lateral drifts and slab moments in flat slab structures under lateral loads. As the slab moment due to lateral loads increases, slab stiffness decreases due to crack formation. The accuracy of the EBWM strongly depends on how the reduced slab stiffness is estimated. For this purpose, this study developed equations for calculating slab stiffness reduction factor by conducting nonlinear regression analysis using stiffness reduction factors estimated from collected test results. The slab stiffness reduction factor is defined as a ratio of reduced slab stiffness due to crack formation to the stiffness of the uncracked slab section. For verifying the proposed equation, the lateral stiffness of two slab–column connection specimens tested by the writers was compared with the lateral stiffness calculated using the EBWM with the proposed stiffness reduction factor. Further, two flat plate specimens having two continuous spans were also considered for verifying the proposed equations for .
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Acknowledgments
The writers acknowledge the financial support provided by the Korea Research Foundation (D01140) and SRC/ERC (R11-2005-056-04002-0). The views expressed are those of the writers, and do not necessarily represent those of the sponsors.
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© 2009 ASCE.
History
Received: Jan 15, 2008
Accepted: Jan 20, 2009
Published online: May 15, 2009
Published in print: Jun 2009
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