PROPERTIES OF POLYPROPYLENE FIBER-REINFORCED CONCRETE

An experimental research investigation of the fresh and hardened mater ial properties of fibrillated polypropylene fiber reinforced concrete is reported. Fiber lengths were 1/2 and 3/4 in., and volume fractions were 0.1, 0.3, and 0.5%. Fiber effects on concrete properties were ass essed. Properties studied were slump, inverted slump cone time, air co ntent, compressive and flexural behaviors, impact resistance and rapid chloride permeability, and volume percent of permeable voids. An inno vative method of characterizing the flexural behavior of fibrillated p olypropylene fiber concrete was proposed. The new method was dependent on the post-peak flexural resistance of concrete. For impact resistan ce and flexural behavior, it was concluded that 3/4-in.-long fibers we re more effective than 1/2-in.-long fibers for volumes of 0.3 percent or less, while 1/2-in.-long fibers were more effective for 0.5 percent volume.