This document summarizes a seminar presentation on fiber reinforced cement concrete. It discusses various types of fibers that can be used for reinforcement, including steel, polypropylene, glass, carbon, and asbestos fibers. Steel fiber reinforced concrete increases compressive strength by 20-30% and fiber length impacts strength. Polypropylene fibers are resistant to chemicals and increase impact resistance and ductility. Fiber reinforced concrete has applications in pavements, water retaining structures, blast resistance structures, precast products, bridge/culvert repairs, and rehabilitation works due to its improved structural properties.

1. SEMINOR ON
FIBER REINFORCED CEMENT CONCRET
PRESENTED BY,
RAJKISHOR G S

2. INTRODUCTION:
Fiber-reinforced concrete (FRC) is concrete containing
fibrous material which increases its structural integrity. It
contains short discrete fibers that are uniformly
distributed and randomly oriented.

3. 1. Steel - Fiber reinforced concrete
2. Non –Fiber reinforced concrete
◦ Polypropylene fiber reinforced cement motor and
concrete
◦ Glass fiber reinforced concrete
◦ Asbestos fibers
◦ Carbon fibers
◦ Organic fibers
◦ Vegetables fibers

4. Steel - Fiber reinforced concrete

5.  A no of steel fiber types are available as reinforcement. Round steel
fiber the commonly used type are produced by cutting round wire in
to short length. The typical diameter lies in the range of 0.25 to
0.75mm. Steel fibers having a rectangular c/s are produced by silting
the sheets about 0.25mm thick.
 Fiber made from mild steel drawn wire. Conforming to IS:280-1976
with the diameter of wire varying from 0.3 to 0.5mm have been
practically used in India.
 Round steel fibers are produced by cutting or chopping the wire, flat
sheet fibers having a typical c/s ranging from 0.15 to 0.41mm in
thickness and 0.25 to 0.90mm in width are produced by silting flat
sheets.

6.  Deformed fiber, which are loosely bounded with water-soluble
glue in the form of a bundle are also available. Since individual
fibers tend to cluster together, their uniform distribution in the
matrix is often difficult. This may be avoided by adding fibers
bundles, which separate during the mixing process
PROPERTIES OF STEEL – REINFORCED CONCRETE
1. The compressive strength of concrete increases by 20 to 30
percent over plain cement concrete
2. 40mm fiber length irrespective of its diameter gives maximum
cube strength as well as cylindrical strength
3. The compressive strength increases with increase in fiber content
in concrete
4. It the concrete to restrains the internal micro cracks

7. Glass fibers

8. Glass fibers is also used in FRC in the form of filaments. Glass
fibers have high tensile strength and high fracture strain, but low
modulus. More ever ordinary borosilicate glass fibers (E-glass) and
soda-lime glass fibers(A-glass) can be easily attacked by alkali
solution in cement based composites and are thus less durable and
should be used with caution. Disadvantages of glass fibers include
low resistance to moisture, sustained loads, and cyclic loads

9. CARBON FIBERS:

10. ◦ Carbon fibers from the most recent & probability the most
spectacular addition to the range of fiber available for
commercial use. Carbon fiber comes under the very high
modulus of elasticity and flexural strength. These are expansive.
Their strength & stiffness characteristics have been found to be
superior even to those of steel. But they are more vulnerable to
damage than even glass fiber, and hence are generally treated
with resign coating.

11. PLASTIC FIBERS:

12. ◦ Fibers such as polypropylene, nylon, acrylic, aramid and
polyethylene have high tensile strength but low young's
modulus thus inhibiting reinforcing effect. Polypropylene and
nylon fibers are found to be suitable to increase the impart
strength. Their addition to concrete has shown better
distribute cracking and reduce crack size.

13. ASBESTOS FIBERS:

14. ◦ Asbestos is a mineral fiber and has proved to be the most
successful fiber, which can be mixed with OPC. The
maximum length of asbestos fiber is 10mm but generally
fibers are shorter than this. The composite has high flexural
strength.

15. POLYPROPYLENE FIBER -REINFORCED CEMENT
CONCRET

16.  Polypropylene is one of the cheapest & abundantly available
polymers polypropylene fibers are resistant to most chemical &
it would be cementitious matrix which would deteriorate first
under aggressive chemical attack. Its melting point is high
(about 165 degrees centigrade). So that a working temp. As
(100 degree centigrade) may be sustained for short periods
without detriment to fiber properties.
 Polypropylene fibers being hydrophobic can be easily mixed as
they do not need lengthy contact during mixing and only need
to be evenly distressed in the mix.
 Polypropylene short fibers in small volume fractions between
0.5 to 15 commercially used in concrete.

17. Main role of fibers is to
◦ Bridge the cracks that develop the concrete
◦ Increase the ductility of concrete elements
◦ Improvement on Post-cracking behavior of concrete
◦ Imparts more resistance to impact load
◦ Controls plastic shrinkage cracking and dry shrinkage
cracking
◦ Lowers the permeability of concrete matrix and thus reduces
the bleeding of concrete
◦ Increase tensile and Impact strength
◦ Improved strain energy and resistance to wear

18.  Pavements and floors: Due the superior properties of structural
properties of steel fiber reinforced concrete(SFRC) it used for overlays
and over slabbing of roads, pavements, airfields and bridge decks,
industrial and other flooring units those subjected to wear and tear, and
attack due to chemical effects.
 Water retaining structures: overhead water tanks underground sumps
need to be watertight. Fibers contribute to control plastic and dry
shrinkage cracks, resulting in water tightness. The steel fiber concrete
has been successfully used in the repair of spilling basin at tarbela dam
in Pakistan.
 Blast resistance structures: the blast wave will cause complex stressing
of the structure compression, tension and shear. Fiber in conjuction
with conventional reinforcement provides the necessary strength to
structure to resist blast.

19.  Precast products: The FRC can also be used for the fabrication of
precast products like pipes, boats, beams, wall panels, stair case
steps, roof panels, manhole covers etc.
 Wearing surface to existing bridges and culverts: FRC has been
used as a wearing surface to existing bridges and culverts in
areas especially troubled by degradation caused through
abrasion by studded types.
 Repairs and rehabilitation works: FRC is cohesive and easy to
work provided fibers are thoroughly mixed in the cement
matrix. It is an ideal material for repair and rehabilitation
works.

20. THANK YOU
PRESENTED BY,
RAJKISHOR G S