Cracking is a major contributor to asphalt pavement deterioration, reducing road quality and increasing maintenance costs nationwide. This study evaluates the cracking performance of a polyolefin aramid fiber-reinforced asphalt mix design used in Jackson County, Oregon, through Indirect Tensile Asphalt Cracking Testing (IDEAL CT) as part of a Balanced Mix Design (BMD) approach. To assess the fiber's potential to improve crack resistance, ten control samples and ten fiber-reinforced samples were prepared, and their crack tolerance index (CTIndex) was compared. The specimens followed the Jackson County job mix formula (JMF), with adjustments to height and air content to meet IDEAL CT specifications. Results showed that the fiber-reinforced samples had a measurable, but not statistically significant, increase in CTIndex compared to the control samples. Analysis also indicated that failure energy (Gf) had no apparent correlation to CTIndex, while the post-peak slope (|m75|) showed a strong correlation for control samples and a moderate correlation for fiber-reinforced samples. Additionally, plant-mixed samples were tested
and showed a measurable but statistically insignificant difference in CTIndex between control and fiber-reinforced mixtures. The results for the laboratory-prepared and plant-mixed samples suggest that polyolefin aramid fiber reinforcement may not improve the cracking resistance of
the Jackson County asphalt mix design.
