This study investigates the behavior and failure modes of fiber-reinforced polymer (FRP) confined concrete wrapped with different FRP schemes, including fully wrapped, partially wrapped, and nonuniformly-wrapped concrete cylinders. By using the same amount of FRP, this study proposes a new wrapping scheme that provides a higher compressive strength

1. 1

2. 2
‫ﺗ‬‫ﺗﻘوﯾﺔ‬ ‫ﺻﻣﯾم‬‫اﻷﻋﻣدة‬‫واﻟﯾ‬‫ﻛرﺑوﻧﯾﺔ‬ ‫ﺎف‬
‫ان‬‫اﺳﺗﻌﻣﺎل‬‫أﻟﯾﺎف‬‫اﻟﺑوﻟﯾﻣر‬Fiber Reinforcement Polymer (FRP)‫ھو‬
‫اﻟﺣل‬‫اﻷﻣﺛل‬‫ﻓﻲ‬‫ﻣﺟﺎل‬‫اﻟﺗﻘوﯾﺔ‬‫اﻟﺧﺎرﺟﯾﺔ‬‫وإﻋﺎدة‬‫اﻟﺗﺄھﯾل‬‫اﻟﺧرﺳﺎﻧﯾﺔ‬ ‫اﻷﻋﺿﺎء‬
‫اﻟﻣﺗﺿررة‬
-‫ھﻲ‬‫ﻣﺻﻧوﻋﺔ‬ ‫أﻟﯾﺎف‬‫ﻣن‬‫ﻣواد‬‫ﻣﻘﺎوﻣﺔ‬‫ﻟﻠﻌواﻣل‬،‫اﻟﻛﯾﻣﯾﺎﺋﯾﺔ‬‫وذات‬‫ﺗﺣﻣل‬‫ﻋﺎﻟﻲ‬
‫ﻟﻼﺟﮭﺎدات‬‫وﻟﮭﺎ‬‫ﻣﻌﺎﻣل‬‫ﺗﻣدد‬‫ﺣراري‬،‫ﻗﻠﯾل‬‫وﻣﻘﺎوﻣﺔ‬‫ﻟﻠﺻدأ‬‫واﻟﺗﺂﻛل‬‫اﻟﻧﺎﺗﺞ‬‫ﻣن‬
‫ﻋواﻣل‬‫اﻟﺗﻌرﯾﺔ‬‫وذات‬‫ﻣروﻧﺔ‬ ‫ﻣﻌﺎﻣل‬‫ﻋﺎﻟﯾﺔ‬‫ﺧﺻوﺻﺎ‬‫اﻷﻟﯾﺎف‬‫ﺑﺎﺳﺗﻌﻣﺎل‬ ‫اﻟﻛرﺑوﻧﯾﺔ‬
‫اﻷﻟﯾﺎف‬‫اﻟزﺟﺎﺟﯾﺔ‬GFRP‫واﻷﻟﯾﺎف‬‫اﻟزﺟﺎﺟﯾﺔ‬‫اﻟﺟﮭد‬ ‫ﻣﺳﺑﻘﺔ‬PGFRP‫ﻓﻲ‬
‫ﺗﻘوﯾﺔ‬‫اﻟﺧرﺳﺎﻧﯾﺔ‬ ‫اﻷﻋﺿﺎء‬‫ﺧﺎرﺟﯾﺎ‬
‫اﻟﻣﺎدة‬‫اﻟراﺑطﺔ‬)‫اﻻﯾﺑوﻛﺳﻲ‬(:
‫ﻋﻣﻠﯾﺔ‬‫ﺗﻐﻠﯾف‬‫اﻟﺧﺎرﺟﻲ‬‫ﻟﻸﻋﺿﺎء‬‫اﻟﺧرﺳﺎﻧﯾﺔ‬‫ﺑﺄﻟﯾﺎف‬‫اﻟﺑوﻟﯾﻣر‬‫ﻻ‬‫ﯾﺗم‬‫إﻻ‬‫ﺑوﺟود‬‫ﻣواد‬
،‫راﺑطﺔ‬‫ﺗﻌﻣل‬‫ھذه‬‫اﻟﻣواد‬‫ﻋﻠﻰ‬‫اﻟﺗﺻﺎق‬‫أﻟﯾﺎف‬‫اﻟﺑوﻟﯾﻣر‬‫ﻋﻠﻰ‬‫ﺳطﺢ‬‫اﻟﺧرﺳﺎﻧﺔ‬‫ﺑﺄﺣﻛﺎم‬
-‫ﻋﺎم‬ ‫ﺑﺷﻛل‬ ‫اﻟﺗﻧﻔﯾذ‬ ‫طرﯾﻘﺔ‬‫اﻟﺳطﺢ‬ ‫ﻋﻠﻰ‬ ‫اﻟﻛرﺑوﻧﯾﺔ‬ ‫اﻻﻟﯾﺎف‬ ‫ﺷراﺋﺢ‬ ‫ﺑﻠﺻﻖ‬ ‫ﺗﻛون‬
‫طرﯾﻖ‬ ‫ﻋن‬ ‫وذﻟك‬ ‫ﻣﺑﺎﺷرة‬ ‫اﻟﺧرﺳﺎﻧﻰ‬:‫اى‬ ‫ازاﻟﺔ‬ ‫و‬ ‫اﻟﻘدﯾﻣﺔ‬ ‫اﻟﺗﺷطﯾب‬ ‫طﺑﻘﺎت‬ ‫إزاﻟﺔ‬
‫ﺧرﺳﺎﻧﻰ‬ ‫ﺳطﺢ‬ ‫اﻟﻰ‬ ‫اﻟوﺻول‬ ‫ﺣﺗﻰ‬ ‫اﻟﺧرﺳﺎﻧﺔ‬ ‫ﺳطﺢ‬ ‫ﻣن‬ ‫ﻣﻔﻛﻛﺔ‬ ‫او‬ ‫ﺿﻌﯾﻔﺔ‬ ‫طﺑﻘﺎت‬
‫ان‬ ‫ﻣن‬ ‫اﻟﺗﺄﻛد‬ ‫ﯾﺟب‬ ‫ﻛﻣﺎ‬ ‫ﺑﺎﻟرﻣﺎل‬ ‫اﻟﺳﻔﺢ‬ ‫او‬ ‫اﻟﺻوارﯾﺦ‬ ‫طرﯾﻖ‬ ‫ﻋن‬ ‫ذﻟك‬ ‫و‬ ،‫ﻗوي‬
‫ﻋن‬ ‫ﺗﻘل‬ ‫ﻻ‬ ‫اﻟﺧرﺳﺎﻧﻰ‬ ‫ﻟﻠﺳطﺢ‬ ‫اﻻﻟﺗﺻﺎق‬ ‫ﻣﻘﺎوﻣﺔ‬1.5‫ﻧﯾوﺗن/ﻣم‬2
-‫اﻟﻛرﺑون‬ ‫اﻟﯾﺎف‬ ‫ﻣن‬ ‫طﺑﻘﺔ‬ ‫ﻣن‬ ‫اﻛﺛر‬ ‫اﺳﺗﺧدام‬ ‫ﯾﻣﻛن‬‫اﻟﻛرﺑوﻧﯾﺔ‬ ‫اﻻﻟﯾﺎف‬ ‫ﻧﺳﯾﺞ‬ ‫)ﻣن‬
‫ﻟﻠﺗﻧﻔﯾذ‬ ‫ﻣﻌﯾﻧﺔ‬ ‫طرق‬ ‫ﺗﺳﺗﺧدم‬ ‫و‬ ‫اﻷﺣﯾﺎن‬ ‫ﺑﻌض‬ ‫ﻓﻰ‬ ‫طﺑﻘﺎت‬ ‫ﺳﺑﻌﺔ‬ ‫اﻟﻰ‬ ‫ﺗﺻل‬ ‫ﻗد‬ (ً‫ة‬‫ﻋﺎد‬
‫اﻟﺣ‬ ‫ﻋن‬ ً‫ا‬‫ﻛﺛﯾر‬ ‫ﺗﺧﺗﻠف‬ ‫ﻻ‬‫اﻟﻌﺎﻣﺔ‬ ‫ﺎﻟﺔ‬
-‫ﻣرور‬ ‫ﺑﻌد‬ ‫اﻟﺗﺷطﯾب‬ ‫طﺑﻘﺎت‬ ‫ﺗﻧﻔﯾذ‬ ‫ﻓﻰ‬ ‫اﻟﺑدء‬ ‫ﯾﻣﻛن‬24‫ﺷراﺋﺢ‬ ‫ﺗﺛﺑﯾت‬ ‫ﻋﻠﻰ‬ ‫ﺳﺎﻋﺔ‬
‫اﻟﻛرﺑون‬ ‫اﻟﯾﺎف‬."

3. 3
‫ﻣﻣﯾزات‬‫اﺳﺗﺧدام‬‫اﻟﯾﺎف‬‫اﻟﻛرﺑون‬
١-‫اﻟوزن‬ ‫ﺧﻔﯾﻔﺔ‬.
2-‫ﺗﺻدأ‬ ‫ﻻ‬.
.٥-ً‫ا‬‫أﺛر‬ ‫ﺗﺗرك‬ ‫ﻓﻼ‬ ‫اﻟﺗﺷطﯾب‬ ‫ﺑطﺑﻘﺎت‬ ‫ﺗﻐطﯾﺗﮭﺎ‬ ‫ﯾﺗم‬
‫ﻋﯾوب‬‫اﻟﯾﺎف‬‫اﻟﻛرﺑون‬:
1.‫واﻟﻘص‬ ‫ﻟﻠﺷد‬ ‫اﻟﻣﻌرﺿﺔ‬ ‫اﻷﻣﺎﻛن‬ ‫ﻓﻰ‬ ‫وﺿﻌﮭﺎ‬ ‫ﯾﺟب‬
2ً‫ا‬‫ﺟد‬ ‫ﻗﺻﻔﺔ‬ ‫ﻣﺎدة‬–‫ﺟﻌﻠﮭﺎ‬ ‫و‬ ‫اﻷﻋﻣدة‬ ‫و‬ ‫اﻟﻛﻣرات‬ ‫ﺳوك‬ ‫ﺗﻛﺳﯾر‬ ‫ﯾراﻋﻰ‬ ‫ﻟذﻟك‬
‫اﻷﻟﯾﺎف‬ ‫ﺗﺗﻛﺳر‬ ‫ﻻ‬ ‫ﻗوﺳﯾﺔﺣﺗﻰ‬.
3‫ﻟﻠﺣرﯾﻖ‬ ‫ﻣﻘﺎوﻣﺔ‬ ‫اى‬ ‫ﻟﮭﺎ‬ ‫ﻟﯾس‬-‫ﯾﻣﻛن‬ ‫ﺣﻣﺎﯾﺔ‬ ‫أﺳﺎﻟﯾب‬ ‫و‬ ‫ﻣﻌﯾﻧﺔ‬ ‫دھﺎﻧﺎت‬ ‫ﯾوﺟد‬
‫ﻟﻠﺣرﯾﻖ‬ ‫ﻣﻘﺎوﻣﺗﮭﺎ‬ ‫ﻟزﯾﺎدة‬ ‫ﺗطﺑﯾﻘﮭﺎ‬.
-‫ﻓﺎﻟﻣﻌروف‬ ‫وﻟﻠﻣﻘﺎرﻧﺔ‬ ‫اﻟﺗﺳﻠﯾﺢ‬ ‫ﻓوﻻذ‬ ‫ﻋن‬ ‫ﻟﻠﺗﻌوﯾض‬ ‫اﻟﺗﻘوﯾﺔ‬ ‫ﻓﻲ‬ ‫اﻟﻣﺎدة‬ ‫ھذه‬ ‫ﺗﺳﺗﺧدم‬
‫ھو‬ ‫اﻟﻔوﻻذ‬ ‫ﻓﻲ‬ ‫اﻟﺧﺿوع‬ ‫اﺟﮭﺎد‬ ‫أن‬4000kg/cm2‫اﻟﻛرﺑوﻧﯾﺔ‬ ‫اﻷﻟﯾﺎف‬ ‫ﻓﻲ‬ ‫ﺑﯾﻧﻣﺎ‬
ً‫ﺎ‬‫وﺳطﯾ‬28000kg/cm2‫ﻻﯾوﺟد‬ ‫ﺑﺄﻧﮫ‬ ‫ﻋﻧﮫ‬ ‫ﺗﺧﺗﻠف‬ ‫واﻧﻣﺎ‬
‫ﺳﯾﻼن‬ ‫ﻋﺗﺑﺔ‬ ‫ﻓﯾﮭﺎ‬

4. 4

5. 5

6. 6
enforcement, asreinforced polymer, FRPfiberThe use of
for concrete structures has been growing rapidly in
recent years.
This paper summarizes the current state of knowledge of
these materials and highlights the various FRP
strengthening techniques that have been used for
concrete and masonry structures.
Material characteristics of FRP and fundamental design
considerations are discussed.
Selection of the appropriate materials and their
corresponding advantages and disadvantages are
highlighted.
Design philosophies for concrete members reinforced
and/or strengthened with FRP are enumerated.
Fundamental flexure, shear and bond be heavier of
concrete members reinforced and/or strengthened with
FRP according to the current ACI design guidelines are
examined.
: ‫اﻟﻛرﺑوﻧﯾﺔ‬ ‫ﺑﺎﻷﻟﯾﺎف‬ ‫اﻟﻣﺳﻠﺣﺔ‬ ‫اﻟﺑوﻟﯾﻣﯾرات‬ ‫ﺑﺎﺳﺗﻌﻣﺎل‬ ‫اﻷﻋﻣدة‬ ‫ﺗﻘوﯾﺔ‬
‫ﻣن‬ ‫طوق‬ ‫ﺑﺎﺳﺗﻌﻣﺎل‬ ‫اﻟداﺋرﯾﺔ‬ ‫أو‬ ‫اﻟﻣﺳﺗطﯾﻠﺔ‬ ‫ﺳواء‬ ‫اﻟﺧرﺳﺎﻧﯾﺔ‬ ‫اﻷﻋﻣدة‬ ‫ﺗﻘوﯾﺔ‬ ‫ﺗﻌﺗﻣد‬
‫اﻟﻣﺳﻠﺣﺔ‬ ‫اﻟﺑوﻟﻣﯾرﯾﺔ‬ ‫اﻟﺻﻔﺎﺋﺢ‬‫وذﻟك‬ ‫اﻟﻛرﺑوﻧﯾﺔ‬ ‫ﺑﺎﻷﻟﯾﺎف‬‫ﻓﻲ‬ ‫ﺗﻧﺗﺞ‬ ‫اﻟﺗﻲ‬ ‫اﻟﻣﻘﺎوﻣﺔ‬ ‫زﯾﺎدة‬
‫ﺗﺣت‬ ‫ﻋﺎﻣﻠﺔ‬ ‫اﻟﻣطوﻗﺔ‬ ‫اﻟﺧرﺳﺎﻧﺔ‬ ‫ﺗﺻﺑﺢ‬ .‫اﻟطوق‬ ‫ھذا‬ ‫ﻣن‬ ‫اﻟﺣﺻر‬ ‫ﻧﺗﯾﺟﺔ‬ ‫اﻟﺧرﺳﺎﻧﺔ‬
‫اﻟﻰ‬ ‫ذﻟك‬ ‫وﯾؤدي‬ .‫اﻟﺑوﻟﯾﻣﯾرﯾﺔ‬ ‫اﻟﺻﻔﺎﺋﺢ‬ ‫ﻣن‬ ‫اﻷﻓﻘﻲ‬ ‫ﺑﺎﻻﺗﺟﺎه‬ ‫ﺣﺻر‬ ‫اﻟﻣﺣور‬ ‫ﺛﻧﺎﺋﻲ‬ ‫ﺿﻐط‬
‫ﻣﻘﺎوﻣﺔ‬ ‫زﯾﺎدة‬‫اﻟﻌﺎﻣود‬.‫اﻟﺷﺎﻗوﻟﻲ‬ ‫ﺑﺎﻻﺗﺟﺎه‬

7. 7

8. 8

9. 9

10. 10
-This study investigates the behavior and failure modes of fiber
reinforced polymer (FRP) confined concrete wrapped with
ferent FRP schemes, including fully wrapped, partiallydif
wrapped, and nonwrapped concrete cylinders. By-uniformly
using the same amount of FRP, this study proposes a new
wrapping scheme that provides a higher compressive strength

11. 11
concrete, in comparison withconfined-and strain for FRP
conventional fully wrapping schemes. A total of 33 specimens
were cast and tested, with three of these specimens acting as
reference specimens and the remaining
specimens wrapped with different types of FRP (CFRP and
GFRP) by different wrapping schemes.
For specimens that belong to the descending branch type,
ad a lower compressivewrapped specimens h-the partially
strength but a higher axial strain as compared to the
wrapped specimens. In addition, the-corresponding fully
wrapped specimens achieved both a higher-no uniformly
compressive strength and axial strain in comparison with
apped specimens.wr-the fully
wrapping scheme changes the-Furthermore, the partially
failure modes of the specimens and the angle of the failure
surface.
A new equation that can be used to predict the axial strain
of concrete cylinders wrapped partially with FRP is
proposed

12. 12

13. 13

14. 14
Design of FRP Axial Strengthening of RCC Columns -
ACI 440.2R-08
Home/ How To Guide / Design of FRP Axial Strengthening of
RCC Columns -ACI 440.2R-08
FRP axial strengthening systems are used to
improve or enhance the capacity of reinforced
concrete columns. It can be used for both circular
and rectangular shaped columns but it is more
effective in the former shape.
In this article the design of FRP axial strengthening
system for columns is discussed.

15. 15
Fig.1: Applying Continuous FRP Systems for Axial
Strengthening of RCC Columns
Advantages of FRP Axial Strengthening Systems for
Columns
 Increases the ultimate load carrying capacity of
reinforced concrete member
 Improves shear capacity of reinforced concrete
element
 Reinforcement bar lap splice capacity of the
member is improved due to FRP axial strengthening
system application
 The ductility of reinforced concrete column is
improved considerably.

16. 16
Design of Axial FRP Strengthening Systems for Columns
FRP axial strengthening is usually conducted by
providing fiber reinforced polymer (FRP) around
reinforced concrete columns. This strengthening
technique is specifically influential when the
column is circular.
However, if the reinforced concrete column is
rectangular and the ratio of depth to width of
column is larger than 2 or the smallest side of the
column is greater than 900mm, then ACI 440.2R-
08 is not applied for this strengthening method.
Figure-2 illustrates the confined area in different
shapes of concrete columns.
Fig.2: Confined Area in Circular, Square and Rectangular
Concrete Columns

17. 17
The ineffectiveness of rectangular or square
column confinement might be attributed to the
non-uniform stress distribution and stress
concentration at the corner of the section. This
may lead to premature failure of strengthened
element.
It is essential to wrap reinforced concrete column
completely with FRPs in order confine and improve
the element effectively. Unlike the flexural and
shear strengthening of reinforced concrete beams,
the FRPs which surround the column activated only
if the member is enlarged laterally and exert
stresses on the FRPs. This means that, beam
strengthening is an active system whereas column
strengthening is a passive system.
The FRP system which wrapped around the column
creates circumferentially uniform confine pressure
that acts against the radial compression
enlargement. Figure-3 illustrates how FRP systems
create a pressure against the compression
expansion of the concrete column.

18. 18
Fig.3: Forces Acted in a Confined Concrete Column

19. 19
Fig.4: Reinforced Concrete Column Confined with
Continuous FRPs
Strengthening of RCC Column Under Pure Compression
The compression strength of reinforced concrete
column can be increased through confinement of
the column. The confinement is achieved by
directing FRP systems around the column
transverse to longitudinal direction of the column.
It should be said that, any FRP system that applied
to in other directions should be ignored.

20. 20
The nominal capacity of short, non-prestressed,
normal weight reinforced concrete column with tie
and spiral reinforcement can be calculated by the
following two equations which is provided by ACI
318-11:
For tie:
For spiral
The confined compressive strength is estimated
using formula provided by ACI 440.2R-08:
If is larger than zero but smaller than , the
following formula is applied:
When is larger than but smaller than , then
the following expression is used:

21. 21
Where:
: Strength reduction factor which 0.75 for spiral
and 0.65 for tie
fc‘: Concrete strength
Ag: Gross concrete area
Ast: Longitudinal reinforcement area
fy: yield strength of longitudinal reinforcement
fc: confined compressive strength
Ec: Concrete modulus of elasticity
: Concrete strain
: Ultimate axial compressive strain of
confined concrete and it can be computed by
applying equation 10 and its value should not
exceed 0.01.
E2 and are slope of linear portion of stress
strain model for FRP confined concrete and
transition strain in stress strain curve of FRP
confined concrete respectively and both may be
estimated by the following equations:

22. 22
The maximum confined concrete compressive
strength (fcc‘) in equation-5 is calculated as follows:
Where:
: Strength reduction factor taken as 0.95
ka: Efficiency factor for FRP reinforcement in
determination of maximum confined compressive
strength and it depend on geometry of cross
section as shown in figure 2. It can be taken as 1
for circular cross section as per the ACI 440.2R-08
recommendation.
fl: Maximum confined pressure because of FRP
system and it is computed as:

23. 23
Where:
Ef: Modulus of elasticity of FRP reinforcement
n: Number of plies of FRP reinforcement
tf: Nominal thickness of one ply of FRP
reinforcement
D: diameter of circular cross section compression
member
: Effective strain level in FRP reinforcement
achieved at failure and can be evaluated using the
following expression:
Where:
: is the FRP strain efficiency factor takes FRP
system premature failure into consideration and it
is usually taken as 0.58

24. 24
: design rupture strain of FRP reinforcement
The maximum axial compressive strain of confined
concrete can be calculated by the following
equations:
Where:
: Maximum strain of unconfined concrete
kb: Efficiency factor for FRP reinforcement and it
can be considered as 1 for circular cross section
based on recommendations of ACI 440.2R-08
fl / fc‘: Confinement ratio and a minimum of 0.08
should be considered as per ACI 440.2R-08
recommendation.
If non-circular cross section is strengthened, the equivalent
diameter should be used in equation 8 as
illustrated in Figure-5:

25. 25
Fig.5: Equivalent Circular Cross Section
And both efficiency factor (ka) in equation-7 and (kb)
are based on the cross-sectional area of effectively
confined concrete (Ae) and (h?b) ratio as can be
observed from the following equations:

26. 26
Where:
rc: Radius of the corner of the section as it can be
seen from figure 5
pg: Longitudinal steel reinforcement ratio
Column Subjected to Combined Axial Compression
and Bending
Reinforced concrete column that is subjected to
both axial compression and bending can be
strengthened by axial FRP strengthening systems.
If the eccentricity is smaller than 0.1h then
equation-1 and equation-2 can be employed to
anticipate the confinement effect on the strength
improvement.
However, when the eccentricity surpasses 0.1h
then the two previous equations is employed to

27. 27
estimate the concrete material properties of the
cross-section element under compression. This will
be used to construct interaction (P-M) diagram,
Figure-6, for the concrete element that has been
confined by FRP systems.
Moreover, there are several restrictions which
should be considered when the member is
subjected to axial compression and bending.
The first condition which should be considered is
that, FRP effective strain must be greater than
0.004.
Moreover, if maximum applied bending moment
and axial force located below the line that connect
the balanced point in the interaction diagram for
unconfined member and the origin, then strength
improvement should not be considered.

28. 28
Fig.6: Interaction Diagram

29. 29
CFRP patterns used to strengthen axially loaded RC walls
with openings

30. 30

31. 31
Methods of FRP strengthening for RC columns: a –
wrapping of

32. 32

33. 33

34. 34

35. 35

36. 36

37. 37

38. 38

39. 39

40. 40

41. 41
.
Exposing Rusted Rebar
First we removed all loose concrete at the surrounding
area of each crack or spall. We then sandblasted to
remove all rust and debris from the exposed reinforcing
steel.
The sandblasting sprayed a good amount of debris in the
air, and to protect the surrounding vehicles we had to be
very creative with our containment during this process.

42. 42