Developing Sustainable Asphalt Mixtures Using High-Density Polyethylene Plastic Waste Material

There is growing interest in sustainable road pavement technologies to protect the environment and provide economic benefits. Post-consumer recycled (PCR) plastics are considered for construction to address the threat of plastic waste materials (PWM) and to improve sustainability. Asphalt pavement construction is highly considered for PWM recycling due to its large daily production. The purpose of this study is to investigate the performance of asphalt mixture containing PWM, specifically high-density polyethylene (HDPE), and compare its performance with two conventional mixtures. Three asphalt mixtures were considered: (1) mixture with asphalt binder PG 76-22 (SBS-modified); (2) mixture with asphalt binder PG 70-22 (SBS-modified); and (3) mixture with binder PG 67-22 and 3% HDPE (the plastic mixture). The rheological properties of the modified asphalt binders and the performance of the modified asphalt mixtures were evaluated. The long-term field performance of the pavements was modeled using AASHTOWare software (v.1.1.6) for the three mixtures considered. The results showed that all the mixtures were able to comply with the cracking threshold specified by the Louisiana Department of Transportation and Development (LaDOTD) for high-traffic volume roads. In addition, the plastic asphalt mixture showed similar performance to the one containing PG 70-22 (SBS-modified) asphalt binder.