الفهرس 
LITERATURE REVIEWOnly 14 pages are availabe for public view
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Abstract
Use of fiber reinforced polymers, FRP in strengthening reinforced
concrete clements, has increased rapidly in the last three decades. FRP is
made of high-tcnsi le-strcngth fibers such as carbon (CFRP), glass
(GFRP), aramid (AFRP). FRP laminates (sheets and strips) are used
widely to strengthen and repair different RC elements. FRP has an
outstanding characteristic since it is corrosion free. This can increase
significantly the service life of structures by reducing concrete
deterioration. Other advantages of FRP laminates of particular interest in
the field of structural applications arc its high strength-to-weight ratio
good fatigue behavior, low relaxation, and easy handling and installation.
The drawbacks of FRP reinforcement include its high cost, brittle failure,
low shear strength, lack of ductility due its linear stress-strain behavior
up to failure, and low tensile strain at ultimatAlthough the FRP has very high tensile strength, this is often not
fully utilized due to the possible debonding between the FRP and the
concrete surface under relatively lower loads. Dcbonding is one of the
main problems regarding the use of externally bonded FRP strips.
Several types of debonding may occur when strengthening concrete
beams with FRP strips. These types can be generally divided into two
main groups: i) plate end dcbonding; where the debonding occurs at the
end of the strip, and ii) intermediate crack debonding; where the
debonding occurs under the flexural or flexural shear cracks. This thesis
aims to investigate the bond characteristics between high strength
concrete beams and carbon fiber reinforced polymers, CFRP. The
intermediate crack dcbonding is the major debonding failure mode.
An experimental program was conducted at the Reinforced
Concrete Research Unit at the Faculty of Engineering, Ain Shams
University to study the behavior of RC beams strengthened by CFRP
strips. The program consists of testing eight simply supported beams with
overall dimensions of 150 rnrn width, 300 mill depth and 3000 nun
length, divided into four groups depending on different parameters. The
first group consisted of three beams varying in compressive strength
(specimens B I to B3). The second group consisted of three beams
varying in bond length (specimens B3, B4 and B6). The third group
consisted of three beams varying in wrapping system (specimens B6 to
B8). The fourth group consisted of two beams varying in concrete cover
(specimens B3 and B5). The analytical phase of this study includes a
rational analysis to predict the behavior of RC beams strengthened with
CFRP strips at the tension side of the beam and GFRP sheets used as U-
wraps. An assessment regarding some of the existing codes provisions