Development of a sustainable semi-flexible pavement composite containing recycled asphalt pavement

Abstract

The purpose of this research is to investigate the feasibility of Recycled Asphalt Pavement (RAP) material in developing sustainable Semi-Flexible Pavement (SFP) composite material. While a lot of effort has been made in the last several years to explore the potential of RAP in bituminous and cement concrete pavement, such an attempt has not been made for emerging alternative pavement structure, such as SFP. SFP holds a unique ability to combine flexibility and rigidity which offers improved durability and performance. In this study, RAP material was integrated into the SFP mix to enhance sustainability while minimizing the dependance on virgin materials. Along with mix design part, different mechanical properties related to strength and durability of SFP composite were evaluated in the laboratory. Various RAP contents (0%, 25%, 50%, and 75% by weight) were assessed to understand their impact on performance. Results indicated that RAP significantly improved the sustainability component of the SFP while maintaining adequate mechanical performance. Particularly, limited laboratory findings indicated reduction in energy requirement with increase in RAP proportion in SFP composite. In addition, increase in RAP content to 75% also satisfied the strength and durability based requirements. The findings demonstrate that this approach can potentially reduce the environmental footprint of road construction while providing a long-lasting pavement solution.