Persistence of Strength/Toughness in Modified-Olefin-Fiber- and Hybrid-Fiber-Reinforced Concrete

This paper investigates the flexural performance of modified-olefin-fiber- (MOF) and hybrid-fiber-reinforced concrete. The standards and methodologies that are commonly used to evaluate the flexural performance of fiber-reinforced concrete are also discussed. Persistence of strength/toughness (PST) was introduced to evaluate the safety and economics of fiber-reinforced concrete. By comparing the modulus of rupture and the limit of proportionality, the PST can be easily and qualitatively obtained. This method agrees with the toughness index. PST can serve as an excellent supplement to the traditional standards and methods that evaluate the strength and toughness of fiber-reinforced concrete. The test results demonstrate that using hooked steel fibers increased the flexural strength and toughness most. The hybridization of the MOFs and the hooked steel fibers, and the addition of MOFs improved the PST.