Ultra-High-Performance Fiber-Reinforced Concrete Composites Incorporating Hybridized Polymer Fibers: Resistance to Static and Impact Loads

This paper investigates the mechanical characteristics (encompassing compressive strength, flexural strength, toughness, and impact resistance) of ultra-high-performance fiber-reinforced concrete (UHPFRC) incorporating polypropylene (PP) and polyvinyl alcohol (PVA) fibers. An experimental program was conducted, based on which the polymer and metallic fibers were used at the same fiber content, and different sets of single and hybrid fiber- reinforced composites were fabricated and tested. Despite the fact that it has been exhibited through previous research that the hybridized PVA-PP fibers do not result in the development of the mechanical characteristics of engineered cementitious composites (ECCs), the UHPC composites incorporating such hybrid fibers show augmented levels of toughness, flexural strength, and resistance to impact loads. A comparison was also made to assess the potentiality of the used fibers in terms of environmental impact and cost. Based on the results, hybridization with PVA and PP fibers leads to remarkable improvement in technical performance and mitigation of the economic and environmental impact of UHPFRC composites.