Fiber Reinforced
Concrete (FRC)
Presented By
Gaurav Singh
131617
Contents
Introduction
Benefits of FRC
Toughening Mechanism
Factor affecting the properties of FRC
Comparison of Mix Proportion of FRC and Plain Concrete
Type of fibers
Steel Fiber Reinforced Concrete (SFRC)
Structural behavior & Durability of SFRC
Problems with SFRC
Application Of FRC
Conclusion
References
Introduction to Fiber Reinforced
Concrete
Concrete containing a hydraulic cement, water , aggregate,
and discontinuous discrete fibers is called fiber reinforced
concrete.
Fibers can be in form of steel fiber, glass fiber, natural
fiber , synthetic fiber.
Benefits of FRC
Main role of fibers is to bridge the cracks that develop
in concrete and increase the ductility of concrete
elements.
Improvement on Post-Cracking behavior of concrete
Imparts more resistance to Impact load
controls plastic shrinkage
shrinkage cracking
cracking
and
drying
Lowers the permeability of concrete matrix and thus
reduce the bleeding of water
Toughening mechanism
Toughness is ability of a material to absorb energy
and plastically deform without fracturing.
It can also be defined as resistance to fracture of a
material when stressed.
Contd.
Reference: Cement & Concrete Institute
http://www.cnci.org.za
Contd.
Source: P.K. Mehta and P.J.M. Monteiro, Concrete: Microstructure, Properties,
and Materials, Third Edition, Fourth Reprint 2011
Factors affecting the Properties of
FRC
Volume of fibers
Aspect ratio of fiber
Orientation of fiber
Relative fiber matrix stiffness
Types of fiber used in FRC
Steel Fiber Reinforced Concrete
Polypropylene Fiber Reinforced (PFR) concrete
Glass-Fiber Reinforced Concrete
Asbestos fibers
Carbon fibers and Other Natural fibers
Steel Fiber Reinforced Concrete
Diameter Varying from 0.3-0.5 mm (IS:280-1976)
Length varying from 35-60 mm
Various shapes of steel fibers
Advantage of Steel fiber
High structural strength
Reduced crack widths and control the crack widths
tightly, thus improving durability
less steel reinforcement required
Improve ductility
Reduced crack widths and control the crack widths
tightly, thus improving durability
Improve impact and abrasionresistance
Structural Behavior of Steel Fiber
Reinforced Concrete
Effect on modulus of rupture
Effect of compressive strength
Effect on Compressive strength & tensile Strength at
fire condition i.e. at elevated temperature
Effect on Modulus of Rupture
Ref: Abid A. Shah, Y. Ribakov, Recent trends in steel fibered high-strength concrete,
Elsevier, Materials and Design 32 (2011), pp 41224151
Effect on Compressive Strength
Ref: Abid A. Shah, Y. Ribakov, Recent trends in steel fibered high-strength concrete,
Elsevier, Materials and Design 32 (2011), pp 41224151
Structural behavior at Elevated
Temperature
Ref: K.Srinivasa Rao, S.Rakesh kumar, A.Laxmi Narayana, Comparison of
Performance of Standard Concrete and Fibre Reinforced Standard Concrete
Exposed To Elevated Temperatures, American Journal of Engineering Research
(AJER), e-ISSN: 2320-0847 p-ISSN : 2320-0936, Volume-02, Issue-03, 2013, pp-
Contd.
Ref: K.Srinivasa Rao, S.Rakesh kumar, A.Laxmi Narayana, Comparison of
Performance of Standard Concrete and Fibre Reinforced Standard Concrete
Exposed To Elevated Temperatures, American Journal of Engineering Research
(AJER), e-ISSN: 2320-0847 p-ISSN : 2320-0936, Volume-02, Issue-03, 2013, pp-
Durability
Resistance against Sea water (In 3% NaCl by weight of
water)
Maximum loss in compressive strength obtained was
about 3.84% for non-fibered concrete and 2.53% for
fibered concrete
Resistance against acids (containing 1% of sulfuric
acid by weight of water)
Maximum loss in compressive strength obtained was
found to be about 4.51% for non-fibered concrete and
4.42% for fiber concrete
Problems with Steel Fibers
1. loss of workability.(It is proportional to volume concentration of fibers in
concrete)
2. Increase in specific gravity of the concrete. This means that the concrete
will be heavier than normal concrete in case of some fibers.
3. Proportioning the exact amount of fibers in the batch of concrete. Test
have shown that a slight variation in fibers creates tremendous changes
in concrete strength.
4. Higher cost because of its control issues (production issues) as well as
the cost of raw material is high.
5. Corrosion of steel fibers. We use fibers to increase the tensile strength
and stiffness and in order to get higher performance of concrete we want
the fibers to perform well. Corrosion will reduce the performance level.
Application of FRC in India & Abroad
More than 400 tones of Steel Fibers have been used
recently in the construction of a road overlay for a project
at Mathura (UP).
A 3.9 km long district heating tunnel, caring heating
pipelines from a power plant on the island Amager into the
center of Copenhagen, is lined with SFC segments without
any conventional steel bar reinforcement.
steel fibers are used without rebars to carry flexural loads
is a parking garage at Heathrow Airport. It is a structure
with 10 cm thick slab.
Precast fiber reinforced concrete manhole covers and frames are
being widely used in India.
Conclusion
The total energy absorbed in fiber as measured by the area
under the load-deflection curve is at least 10 to 40 times
higher for fiber-reinforced concrete than that of plain
concrete.
Addition of fiber to conventionally reinforced beams
increased the fatigue life and decreased the crack width
under fatigue loading.
At elevated temperature SFRC have more strength both in
compression and tension.
Cost savings of 10% - 30% over conventional concrete
flooring systems.
References
K.Srinivasa Rao, S.Rakesh kumar, A.Laxmi Narayana,
Comparison of Performance of Standard Concrete and Fibre
Reinforced Standard Concrete Exposed To Elevated
Temperatures, American Journal of Engineering Research
(AJER), e-ISSN: 2320-0847 p-ISSN : 2320-0936, Volume-02,
Issue-03, 2013, pp-20-26
Abid A. Shah, Y. Ribakov, Recent trends in steel fibered
high-strength concrete, Elsevier, Materials and Design 32
(2011), pp 41224151
ACI Committee 544. 1990. State-of-the-Art Report on Fiber
Reinforced Concrete.ACI Manual of Concrete Practice, Part
5, American Concrete Institute, Detroit,MI, 22 pp
Contd.
P.K. Mehta and P.J.M. Monteiro, Concrete: Microstructure,
Properties, and Materials, Third Edition, Fourth Reprint
2011, pp 502-522
ACI Committee 544, Report 544.IR-82, Concr. Int., Vol. 4,
No. 5, p. 11, 1982
Hanna, A.N., PCA Report RD 049.01P, Portland Cement
Association, Skokie, IL, 1977
Ezio Cadoni ,Alberto Meda ,Giovanni A. Plizzari, Tensile
behaviour of FRC under high strain-rate,RILEM, Materials
and Structures (2009) 42:12831294
Marco di Prisco, Giovanni Plizzari, Lucie Vandewalle, Fiber
Reinforced Concrete: New Design Prespectives, RILEM,
Materials and Structures (2009) 42:1261-1281
