Abstract




 
   

IJE TRANSACTIONS B: Applications Vol. 22, No. 2 (August 2009) 131-146   

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  FLEXURAL TESTING OF HIGH STRENGTH REINFORCED CONCRETE BEAMS STRENGTHENED WITH CFRP SHEETS
 
 
S.H. Hashemi*

Faculty of Engineering, Arak University
P.O. Box 38139, Arak, Iran
hamidhashemi55@yahoo.com

R. Rahgozar and A.A. Maghsoudi

Department of Civil Engineering, University of Kerman
P.O. Box 76169-14111, Kerman, Iran
rahgozar@mail.uk.ac.ir - maghsoudi.a.a@mail.uk.ac.ir

* Corresponding Author
 
 
( Received: April 30, 2007 – Accepted in Revised Form: September 25, 2008 )
 
 

Abstract    The objective of this study is to investigate the effectiveness of externally bonded CFRP sheets to increase the flexural strength of reinforced high strength concrete (HSC) beams. Four-point bending flexural tests to complete failure on six concrete beams, strengthened with different layouts of CFRP sheets were conducted. Three-dimensional nonlinear finite element (FE) models were adopted by ANSYS to examine the behavior of the test beams. More specifically, the strength and ductility of the beams is investigated, as the number of FRP layers and tensile reinforcement bar ratio changed. With the exception of the control beam, one to four layers of CFRP were applied to the specimens. The ductility characteristics of the test beams were evaluated in terms of the displacement, curvature and energy ductility index. It was found that for all the reported beams, the energy ductility value is about two times higher than the displacement ductility values. The crack patterns in the beams are also presented. The load deflection plots obtained from numerical study show good agreement with the experimental results.

 

Keywords    Ductility, Finite Element Model, FRP, High Strength Concrete

 

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