This document discusses fiber reinforced concrete (FRC). It provides a history of fiber usage in concrete, describes different fiber types including steel, plastic, glass and natural fibers. The document discusses why fibers are used to improve properties like toughness, tensile strength and ductility. It also covers factors affecting FRC properties, advantages and disadvantages, applications, and includes a case study on steel fiber reinforced concrete pavement.

1. 1
Submitted By -
SHRINIVAS KALBHOR
(T.E. Civil)
Roll No - 22
Guided By -
Prof. Awad S. R.

2. Contents
 History
 General Introduction
 Why fibres are used?
 What is Fibre Reinforced Concrete
 Types of Fibres
 Factors affecting properties of FRC
 Advantages and Disadvantages of FRC
 Applications of FRC
 Case study
 Conclusion
 References 2

3. History
 Horse hair was used in mortar and straw in mud
bricks
 Asbestos fibers were used in concrete in the early
1900
 Steel , Glass and synthetic fibers have been used to
improve the properties of concrete since past 30 to
40 years

4. General
 Concrete is relatively brittle, and its tensile strength is
typically only about one tenths of its compressive
strength.
 Regular concrete is therefore normally reinforced with
steel reinforcing bars.
 For many applications, it is becoming increasingly
popular to reinforce the concrete with small, randomly
distributed fibers.
 Their main purpose is to increase the energy
absorption capacity and toughness of the material, but
also increase tensile strength of concrete.
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5. Why fibers are used?
 Main role of fibers is to overcome the cracks that
develop in concrete and increase the ductility of
concrete elements
 There is considerable improvement in the post-
cracking behavior of concrete containing fibers
due to both plastic shrinkage and drying shrinkage
 They also reduce the permeability of concrete and
thus reduce bleeding of water
 Imparts more resistance to Impact load

6. Fiber Reinforced Concrete
 Definition
 Concrete containing a cement, water, fine and coarse
aggregate and discontinuous discrete fibers is called
Fiber Reinforced Concrete (FRC).
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7. Types of Fibers
 Following are the types of Fibers used in FRC
1. Steel fibers
2. Plastic fibers
1. Polyester 2. polypropylene 3. polyethylene.
3. Glass fibers
4. Natural Materials
1. Wood cellulose 2. Bamboo 3. Elephant Grass
5. Asbestos fibers
6. Carbon fibers
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8. Steel fiber
 Diameter vary from 0.25 to 0.75 mm
 Hooks are provided at the ends to improve bond with
the matrix
 Various shapes of steel fibers :

9. Plastic fibers
 Cheap, abundantly available
 High chemical resistance
 High melting point
Propylene fibers

10. Natural materials
 Bamboo, elephant grass, jute, wood cellulose are
examples
 They may undergo organic decay
 High impact strength
Jute fiber Bamboo fiberElephant grass

11. Asbestos fibers
 High thermal and chemical resistance
 Short in length
 Flexural strength is 2 to 4 times that of unreinforced
matrix
 Contains 8 to 16% of asbestos fibers by volume

12. Carbon fibers
 Material of future, expensive
 High tensile strength of 2110 to 2815 N/mm2
 Strength and stiffness superior to that of steel

13. Mixing
 Cement content
 325 to 550 kg/m3
 W/C Ratio
 0.4 to 0.6
 Maximum aggregate size
 10mm
 Fiber content
 0.5 to 2.5 % by volume of mix

14. Advantages of FRC
 Improves toughness of concrete
 Improves tensile strength
 More economical than steel reinforcement
 Can be made into thin sheets or irregular shapes
 Gives an alternative way to reinforce concrete other
than traditional steel bars

15. Disadvantages of FRC
 Greater reduction of workability
 High cost of materials

16. Fiber Reinforced Concrete Normal Reinforced
concrete
• High Durability • Lower Durability
• Protect steel from
Corrosion
• Steel potential to
corrosion
• Lighter materials • Heavier material
• More expensive • Economical
• With the same volume,
the strength is greater
• With the same volume,
the strength is less
• Less workability • High workability as
compared to FRC.

17. PCC FRC

19. Areas of application of FRC materials
 Pipes
 Thin sheets
 Shotcrete
 Curtain walls
 Precast elements
 Tiles
 High way and airport pavements
 Canal linings, sewer lining
 Prefabricated shapes

20. Applications of FRC in India
 More than 400 tones of Steel Fibers have been
used in the construction of a road overlay for a
project at Mathura (UP)
 Precast fiber reinforced concrete manhole covers
and frames are being widely used in India

21. Case Study
 Providing and laying 40 mm steel fibre reinforced
cement concrete in pavement (in panels having area not
more than 1.5 m2) consisting of steel fibre @ 40kg per
cubic meter of concrete and cement concrete mix of
1:1.95:1.95 over existing surface.
 Since in the executed item, the thickness was to be
restricted.
 The fibre reinforced concrete has been provided in small
panels considering the workability.

22. Glass fiber reinforced concrete mix

23. FRC Pipes Precast manhole covers
FRC Tiles FRC tunnel walls

24. Conclusion
 The total energy absorbed in fiber is at least 10 to 40
times higher for fiber-reinforced concrete than that of
plain concrete.
 There are many different types of fiber that can be
used for concrete reinforcement.
 It is an economical way to reinforced concrete
compared to regular steel.
 At high temperature SFRC have more strength both in
compression and tension
 Cost savings of 10% - 30% over conventional steel
reinforcement
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25. References
 Mamlouk, Michael, and John Zaniewski. Materials for Civil and
Construction Engineers. Second Edition. N.J.: Pearson Hall, 2006. 576.
Print
 Mehta, P.K., and P.J.M Monteiro. "Fibers in Concrete." University of
Californa, Berkeley, 04,May,2006. Web. 1 Dec 2010.
<http://www.ce.berkeley.edu/~paulmont/241/fibers.pdf
 SMiRT 19, . "WOKSHOP ON: Fiber Reinforced Concrete." ASMiRT,
17,August,2007. Web. 1 Dec 2010. <http://www.iasmirt.org/iasmirt-
2/SMiRT19/SMiRT19_WH3_Tatnall.pdf>.