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http://dx.doi.org/10.12652/Ksce.2011.31.1A.019

Analysis of Confinement Effectiveness for FRP Confined Concrete Columns  

Choi, Eunsoo (홍익대학교 토목공학과)
Choi, Seung-Hwan (홍익대학교 토목공학과)
Publication Information
KSCE Journal of Civil and Environmental Engineering Research / v.31, no.1A, 2011 , pp. 19-24 More about this Journal
Abstract
Concrete columns strengthening effect due to FRP (Fiber Reinforced Polymer) confinement depends on the elastic modulus of the FRP. This study analyzes the retrofitting effect of FRP confinements according to elastic modulus of FRPs using the existing data and suggests a practical model to assess the strengthening effect. This study subdivides the FRP elastic modulus into three parts based on normal concrete and steel elastic modulus. The slope and the y-axis intersection seem to increase with increasing FRP elastic modulus. In addition, the strengthening effect does not develop up to some amount of FRP confinement having relatively smaller elastic modulus than the compressive elastic modulus of concrete. In this case, a linear model to assess the strengthening effect is hard to be used. Thus, this study suggests that the FRP jackets having 2 times larger elastic modulus than that of concrete are recommended to be used for retrofit of concrete and that a linear model can be applied for the case. The suggested model shows nearly the same result regardless to the restraint of the y-axis intersection. This has been observed at the model of steel confinement and, thus, is a reliable result.
Keywords
FRP; Confinement effect; Concrete; Elastic modulus;
Citations & Related Records
Times Cited By KSCI : 1  (Citation Analysis)
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