Investigating the influence of polyethylene terephthalate fibres with different lengths on the cracking resistance of high-performance asphalt concrete

High-performance asphalt concrete is an innovative paving material that typically relies on the properties of polymer-modified asphalt binders. However, the application is limited due to their high cost and phase separation issues. A solution is explored in the present study by blending 12% asphaltenes and a straight-run asphalt binder with a true performance grade of 70.2–25.9, resulting in a true performance grade of 82.9–21.8, which elevates the binder’s stiffness. Three lengths of polyethylene terephthalate fibres are used to improve the cracking resistance of these asphaltenes-modified mixes. An indirect tensile cracking test is conducted at 25 and 37 °C, revealing a significant improvement in cracking tolerance and failure energy, particularly at 37 °C. The cracking tolerance index value peaked at 105 for 12 mm polyethylene terephthalate fabricated sample, while control asphaltenes-modified, 6 mm, and 18 mm polyethylene terephthalate fabricated samples achieved 61, 87, and 99, respectively, with failure energy increasing with longer fibres.