Preliminary design of recyclable epoxy asphalt: Regeneration feasibility analysis and environmental impact assessment

Epoxy asphalt is a construction material for pavement structures and has been widely used due to excellent durability and longevity characteristics. Although the asphalt phase could be compensated after epoxy asphalt aging, the epoxy resin phase cannot be regenerated at high value due to irreversible covalent cross-links, resulting in reclaimed epoxy asphalt pavement (epoxy RAP) being employed as aggregate. In this paper, with consideration toward its nonrenewable characteristic, a recyclable epoxy asphalt is designed preliminarily based on the reversible principle of dynamic covalent bonds, thus focusing on the principle of circular economy and reducing environmental impact. The molecular design of recyclable epoxy asphalt was conducted to justify it theoretically. An environmental impacts assessment is used to analyze energy consumption and carbon footprint caused by using reclaimed recyclable epoxy asphalt pavement (recyclable epoxy RAP) in asphalt mixture manufacturing. The analysis of molecular design showed the feasibility of recyclable epoxy asphalt regeneration. And the mixture containing recyclable epoxy RAP could reduce the emission of GHGs by 34% compared with the epoxy RAP, although the consumption of energy is approximate. Based on molecular design and environmental impacts evaluation, the sustainability of recyclable epoxy asphalt is verified.