Performance Evaluation of Polyethylene Terephthalate Fiber-Modified High-Performance Asphalt Concrete Utilizing the Balanced Mix Design Approach

Surface distresses such as rutting and cracking shorten the service life of asphalt pavement, requiring a constant need for maintenance or replacement. Developing high-performance asphalt concrete (HPAC) provides a viable solution by offering enhanced durability and resilience to such common issues. This study investigated the potential of HPAC to extend pavement life through the synergistic effects of asphaltenes and polyethylene terephthalate (PET) fibers. Control mixes, made with a crude oil asphalt binder (Binder H), were compared with Binder H-A mixes containing 12% asphaltenes by weight of binder. Variants of HPAC incorporating 0.15% PET fibers of three lengths (6, 12, and 18 mm) were evaluated using the balanced mix design (BMD) principle. Testing included the indirect tensile asphalt cracking test for evaluating cracking resistance at temperatures of 25°C and 37°C, and the Hamburg wheel-track test for evaluating rutting resistance at 60°C. Results show that the optimal length of PET fiber was 12 mm in that HPAC-12mm shows the highest improvement in CTIndex and fracture energy by 16% and 8% at 37°C, respectively compared to the corresponding Control mix values at 25°C, indicating improved resistance to crack initiation and propagation. In addition, HPAC-12mm achieved a rutting resistance index that is more than four times higher than that of the Control mix, which showed signs of moisture susceptibility. The performance space diagram analysis also demonstrates that the combined modification approach shifted HPAC mixtures toward the Super Mix quadrant, indicating superior performance against rutting and cracking.