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http://dx.doi.org/10.12652/Ksce.2015.35.1.0039

Experimental and Analytical Study on the Fracture Strength of RC Beams Strengthened for Flexure with GFRP Involving the Debonding of FRP Reinforcement  

Lee, Jong-Han (Daegu University)
Kwon, Hyuck Bae (Daegu University)
Kang, Su Tae (Daegu University)
Publication Information
KSCE Journal of Civil and Environmental Engineering Research / v.35, no.1, 2015 , pp. 39-48 More about this Journal
Abstract
Reinforced concrete (RC) structures strengthened with FRP materials would cause the loss of the reinforcing effect and the sudden failure of the structure due to the debonding of FRP. The debonding fracture strength of the FRP-strengthened concrete structures has been evaluated using the same strength method as applied in RC structures based on the debonding strain of FRP. However, the values of the FRP debonding strain are different according to design guidelines. Thus, this study carried out an experimental study on RC beams reinforced with GFRP and evaluated the debonding fracture strength of the strengthened beams from each design guideline. Since the debonding failure occurs prior to reaching the ultimate value of concrete compressive strain, this study accounts for the nonlinear stress distribution of concrete. This study also proposed equations that can evaluate the debonding strength of GFRP-strengthened RC beams with similar safety to the ultimate flexural strength of non-strengthened RC beams.
Keywords
Reinforced concrete; Structural reinforcement; FRP; GFRP; Nonlinear analysis; Ultimate flexural strength; Debonding fracture strength; Debonding strain;
Citations & Related Records
Times Cited By KSCI : 1  (Citation Analysis)
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