Toughness Characterization of Fiber Reinforced Concrete Beam using Fracture Mechanics

The study of fracture mechanics was very much essential because it gives clear idea of arising and propagation of cracks, cause for failure, life of structure, etc. The main aim of this research was to study the fracture behavior of fiber reinforced concrete which was reinforced with polypropylene fiber. The fiber used in concrete with different volume fraction like 0.5%, 0.75% and 1% of total volume of cementitious material. The specimens were prepared with different grades of concrete with different dosage of fiber and then subjected to three point bending test. Using test results the fracture properties like fracture energy, flexural strength; stress intensity factor, fracture toughness and stiffness were found. The experimental results showed that effectiveness of polypropylene fiber for different grades of concrete that is normal, medium and high strength concrete increases with increase in fiber volume and also the fracture properties of fiber reinforced concrete increases with increase in fiber volume and effectiveness of fiber was found for dosage of about 0.75-1% volume.