Eco-economic analysis of utilizing high volumes of recycled plastic and rubber waste for green pavements: A comparative life cycle analysis
Haider Ibrahim, Gohar Alam, Ahmed Faheem
Abstract
The strategic repurposing of substantial volumes of plastic waste and end-of-life tires into asphalt pavement presents a compelling practical solution to the growing waste accumulation problem. Adopting a comparative LCA and LCCA approach, this study focuses on the environmental, functional, and economic performance of hot mixed asphalt (HMA) produced with various compositions to determine the most sustainable solution in the local context. The compositions included unmodified, styrene butadiene styrene (PMB), and the novel recycled composite produced with devulcanized rubber and waste low-density polyethylene (DVR + LDPE composite) HMAs. Research findings indicate that HMA modified with DVR + LDPE composite outcompete the traditional counterparts by significantly reducing GHG emissions by 54.5 % and 14.4 % compared to unmodified and PMB HMAs, respectively. The same can be extended to the cost analysis. The discussion emphasizes the practicality and significance of the novel waste composite and stresses adopting a complete life cycle perspective for asphalt sustainability assessment. • Waste plastic-rubber HMA outperforms traditional HMAs in sustainability and cost. • Prioritize long-term sustainability over initial cost savings and emissions. • Focusing solely on the HMA production emissions and costs can be misleading. • Each km of single-lane HMA layer can use 8.6 tonnes of plastic and rubber waste. • At SCC priced at $185/ton CO 2eq , waste HMA saves $36,955/km over HMA-NB, $5177 over HMA-PMB.