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http://dx.doi.org/10.4334/JKCI.2008.20.2.239

Pseudo-Ductile Hybrid FRP Sheet for Strengthening Reinforced Concrete Beams  

Ha, Sang-Su (Center for Construction Engineering Research, Hankyong National University)
Choi, Dong-Uk (Dept. of Architectural Engineering, Hankyong National University)
Lee, Chin-Yong (CareCon, Co., Ltd)
Kim, Kil-Hee (Dept. of Architectural Engineering, Kongju National University)
Publication Information
Journal of the Korea Concrete Institute / v.20, no.2, 2008 , pp. 239-247 More about this Journal
Abstract
Use of both carbon fiber (CF) and glass fiber (GF) at the same time to strengthen existing flexural members was exploited. Using a proper volumetric GF / CF ratio, the CF can rupture first followed by subsequent rupture of GF at higher stress and strain showing a pseudo-ductile behavior. A theoretical study indicated that the ratio is 4.62 : 1 and higher where the pseudoductile effect can be shown. Flexural tests of plain concrete beams strengthened using fibers were first carried out. Hybrid FRP sheet using 8.8 : 1 ratio was then fabricated and the sheet was used to strengthen reinforced concrete beams. The RC beams strengthened using 1-ply and 2-ply hybrid sheets both revealed increased strength over a non-strengthened beam and ductile flexural behavior. A comparable beam strengthened using CF also showed increased strength but with limited ductility.
Keywords
hybrid; pseudo-ductile; fiber reinforced polymer; flexural strengthening; FRP sheet;
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