Study on Flexural Behavior of Reinforced Concrete with Polypropylene and Crimped Steel Fibers

The process of construction evolves day by day with new techniques and materials. Since the materials used in the construction process are nonrenewable, we are in need of new materials and methods to make the construction process sustainable. In this research work, we are going to use such materials to make reinforced concrete a better material for construction. The materials that we are using in the concrete should enhance the flexural and shear strength of the concrete. The materials we are using should be user-friendly, readily available material, and economical. This study presents the flexural and shear behavior of the crimped steel fibers and polypropylene fibers in the reinforced concrete specimens. In this research work, the structural behavior of fiber-reinforced beams is evaluated under the two-point loading test. The percentages of fibers used in the research work are varied and casted. In addition, the design of steel fiber-reinforced concrete beam is adapted to the design of polypropylene fiber-reinforced concrete beam to validate its design. Short fibers are mixed along with the conventional size fibers to improve the flexural strength and brittleness of the concrete. Zigzag stirrups are provided to improve the strength of the concrete. Four different types of concrete specimens were prepared, namely conventional concrete (0% fibers), crimpled steel fibers + polypropylene fibers (CSF + PF) (0.4% + 0.4%), crimpled steel fibers + polypropylene fibers (CSF + PF) (0.8% + 0.8%), and crimpled steel fibers + polypropylene fibers (CSF + PF) (1.2% + 1.2%). The specimens are subjected to curing and testing after 28 days. It has been found that the compressive strength, crimpled steel fibers + polypropylene fibers CSF + PF (1.2% +1.2%) is 21% more than the control specimen. The split tensile strength is 32.21% more for the crimpled steel fibers + polypropylene fibers CSF + PF (1.2% +1.2%) specimen when compared to the control specimen, and the flexural test implicates that the crimpled steel fibers + polypropylene fibers CSF + PF (1.2% +1.2%) is 61% more than the control specimen. In addition to the concrete specimens, the beam elements are also cast with the above-mentioned percentage of crimpled steel fibers (CSF) and polypropylene fibers (PF). The beam element was subjected to the two-point loading test, and the results were discussed.