Ultimate Moment Capacity of Polypropylene Fibers Reinforced Concrete Beams

Abstract

The flexural behavior of polypropylene fiber reinforced concrete, plain concrete beams with and without
reinforcement was investigated. The reinforcement, volume ratio of polypropylene fiber and surface type of
polypropylene fiber kept constant for all the beams. All beams had the same dimensions and tested under two
point loads. The results showed that polypropylene fibers were effective in reducing the crack width and crack
propagation. The results also showed that while polypropylene fibers had only slight effect on the beam
stiffness, combining polypropylene fibers, and reinforcement improved the behavior of reinforced concrete
beams and changed its failure mode. Also from the results it was observed that introduction of polypropylene
fiber significantly improves the cracking behavior. However, only marginal improvement was observed in the
case of ultimate load.
Keywords: Polypropylene fibers, reinforced concrete beams, plain concrete beams, flexural strength, crack