Evaluation of strength parameters of plain and reinforced concrete with the addition of polypropylene fibers

This research investigates the influence of incorporating small-diameter polypropylene fibers on the mechanical properties of concrete. The studied concrete properties include compressive strength, tensile strength, flexural strength (both plain and reinforced), shear strength, and the mitigation of shrinkage cracks. A total of 92 specimens were meticulously fabricated in the laboratory, comprising cylinders (12 inches in length and 6 inches in diameter), beams (20 x 4 x 4 inches), larger beams (60 x 9 x 9 inches), and slab panels (48 x 48 x 4 inches). During the specimen casting process, a consistent mix with a ratio of 1:2:4 and a water-cement ratio of 0.60 was consistently applied. The polypropylene fiber content varied at 0%, 0.2%, 0.4%, and 0.6% for each property examination. Results indicate a positive impact on all concrete properties studied upon the addition of polypropylene fibers. However, the optimal percentage of polypropylene fibers exhibited variability for each variable and property under investigation. This research contributes insights into the nuanced effects of polypropylene fibers on concrete properties, providing a basis for further exploration and practical application in optimizing concrete performance and durability.