Abstract :
Concrete is a versatile material used in the construction industries during the past few decades because of its work ability to cast into any shape using formworks. Cement is nowadays commonly available throughout the world with the recent advancements in manufacturing technology. Reinforced Cement Concrete has gained popularity as the best suited structural material in the construction industry. Fibre Reinforced Cement Concrete is gaining popularity with its inherent advantages like enhanced tensile strength and toughness when compared with conventional reinforced cement concrete. Lightweight Concrete (LC) is also gaining importance in the recent years for several structural applications due to its advantages like reduced dead weight of components, low handling costs having enhanced mechanical and durability properties.
The polypropylene fibres were subsequently improved intoshort fibrillated materials in the construction industries. The polypropylene is a high molecular weight material acquired from monomer C3H6 which is completely a hydrocarbon.PPF has a normal atomic arrangement in the polymer molecule and is also highly crystalline. It is grasped as isotactic polypropylene PPF resistant To contact with more destructive chemicals, its hydrophobic surface not being wet by cement paste accommodates to hold-off chopped fibres from balling effect while mixing like other fibres. The familiarization devises the film weak in the lateral direction which promotes fibrillation. The cement matrix can enter in the mesh structure between the individual fibrils and create a mechanical bond amongst cement matrix and fibre.
The American Society for Testing and Materials published ASTM A-820 code provision is available for steel fibres. Deformed steel fibres provide a good mechanical bond within the concrete matrix to withstand pull-out. Steel fibres mainly transform the brittle concrete into a ductile one. Catastrophic failure of concrete is practically reduced. Steel fibres are added in the concrete matrix during the mixing of its constituent ingredients. Its main advantage is, decrease the steel reinforcement requirements, Overcome crack widths, Improve impact resistance, abrasion resistance, and freeze thaw effects.
Keyword :
polypropylene fibres, Deformed steel fibres, Catastrophic failure, impact resistance, compressive strength, flexure and tensile strength.