Application of Recycled Polyethylene Terephthalate Fiber in Asphaltic Mix for Fatigue Life Improvement

The study aim is to determine the suitability of recycled polyethylene terephthalate (PET) fiber in fatigue life improvement of asphalt concrete mix. Fatigue crack is among the principal distresses that shortens the life span of flexible pavements. The aim was achieved through laboratory experiments (indirect tensile stiffness modulus and fatigue tests) to determine the fatigue characteristics of reinforced and neat asphalt mixtures. The reinforced mixtures were prepared using recycled PET fiber at 0.3, 0.5, 0.7, and 1.0% by total weight of mixture. The result was analyzed through regression analysis and fatigue life-prediction models were developed. The stiffness modulus of reinforced mixtures was improved by 19% at 0.3%, 34% at 0.5%, 4% at 0.7% and decreased by 34% at 1.0% recycled PET fiber reinforcement compared to neat mixture. The developed fatigue life-prediction models are statistically significant with p-values < 0.05. The fatigue life of recycled PET fiber reinforced mixtures at higher strains was highly improved at 0.3% reinforcement, while 0.5% reinforcement exhibited higher fatigue life at lower strain levels compared to neat mixtures. Therefore from the result and analysis conducted, recycled PET fiber has proved to be effective in fatigue life improvement of asphalt concrete.