Evaluation of recycled asphalt pavement using economic, environmental, and energy metrics based on long-term pavement performance sections

Abstract

Recycled materials have been used in roadway construction for years. Recently, with the advancement of material processing equipment and mix design technologies involving Recycled Asphalt Pavement (RAP), RAP’s use in pavement construction is increasing. RAP’s various desirable properties spur its use in sustainable development. These merits include energy conservation in mix production, cost savings in material consumption, and environmental protection. Although asphalt mix is considered to be recyclable – meaning RAP could be a sustainable material – in-depth studies verifying and quantifying its effectiveness are limited in the literature. Based on real-world data from pavements constructed with 35% RAP and virgin mixes, this study comprehensively evaluates the sustainability of RAP from three different aspects including cost, energy, and environment. The life cycle cost analysis based on RealCost and life cycle assessment based on PaLATE is used to compare RAP and virgin alternatives. The results suggest that using RAP is more economically efficient and environmentally viable than virgin pavement if thin asphalt overlay is involved. The findings of this study support RAP’s use in current pavement rehabilitation practice, which usually involves relatively thin asphalt overlays.