Steel fiber reinforced concrete provides superior resistance to cracking and crack propagation due to increased tensile strength in concrete structures.
Applications of Steel Fiber Reinforced Concrete
It is known that plain cement concrete does not have good tensile properties to resist flexure in structural members. In case of concrete reinforcement steel, cracks still appear on the tension face due to bending.
So, to prevent cracking of concrete, especially in the case of water retaining structures, or water transporting structures, it is advisable to design structural concrete as uncracked section. This results in heavy structural design with resulting in high cost.
Steel fiber reinforced concrete is a low cost solution for uncracked section design of concrete members. Use of steel fiber reinforcement in concrete enhances the ability of structural members to carry significant stresses. The use of fibers increases the toughness of concrete under any type of loads. Fibers in concrete has the ability absorb more energy.
As recommended by ACI Committee 544, steel fiber reinforced concrete is used as supplimentary material to prevent cracking, to improve resistance to impact or dynamic loading and to prevent material disintegration.
A guide to design of concrete structures with steel fiber reinforcement has also been published by American Concrete Institue.
The applications of Steel Fiber reinforced concrete are for so varied and so widespread, that it is difficult to categories them. Following are the common applications of steel fiber reinforced concrete constructions:
- Tunnel linings
- Burial Vaults,
- Septic Tanks,
- Roller compacted concrete with steel fibers
Application of Steel Fiber Reinforced Concrete in other Structures:
A) Highway And Airfield Pavements:
- Repair of existing pavement.
- Reduction in pavement thickness.
- Increase in resistance to impact.
- Increase in transverse and longitudinal joint spacing
- Smooth riding surface.
B) Hydraulic Structures:
- Resistance to cavitations or erosion damage.
- Repair of spilling basin.
C) Fiber Shotcrete (FRS):
The inclusion of steel fibers in shotcrete improves many of the mechanical properties of the basic material viz the toughness, impact resistance, shear strength, flexural strength, and ductility factor.FRS has been used for
- Rock stabilization, tunnels, dams, mines.
- Bridges arches, dome structures, power-house
- Stabilization of slopes to prevent landslides repair of deteriorated concrete surface, water channel etc.
A seminar report on fiber reinforced concrete is available which provides more information and mix design of fiber reinforced concrete. The technology used for production, properties and structural use of fiber reinforced concrete is also explained.