Comparative environmental performance of pavement structures considering recycled materials and regional differences

Author(s)

Mascarenhas, Zila M. G. ; Piao, Zhengyin ; Vasconcelos, Kamilla L. ; Poulikakos, Lily D. ; Bernucci, Liedi L. B.

• Document type: Journal article
• Source: Science of The Total Environment; v. 858, p. 11-pg., 2023-02-01.

Abstract

The construction of pavements incorporating reclaimed asphalt pavement (RAP) is taking place around the world, implying the necessity to quantify their net environmental impacts. Life cycle assessment (LCA) is a popular method to analyze the environmental impacts of a product along the whole value chain, providing guidance to practices and technologies from environmental perspectives. However, the LCA research of RAP-modified pavement is seldom performed in Brazil. In addition, as an important source of uncertainties, there is also need of discussion regarding the geographical and technological characteristics in the LCA of pavements. For these motivations, this paper performs a cradle-to-gate LCA to compare the environmental performance of asphalt pavement in Brazil and Switzerland, using the practical rates of RAP use. The functional unit was defined based on the same traffic volume and service life of asphalt pavements, where the mix design and pavement structures follow the standards of the two countries. The results showed that RAP recycling can improve the environmental performance of hot asphalt mixtures in both countries. Binder amount has a high environmental burden and its reduced use by adding RAP has a positive environmental effect. Type of fuel also plays an important role in LCA. In Brazil, it is not recommended to use heavy oils as fuel during the mixing process if other options such as methane gas is available. The results show that the Swiss production of asphalt mixture had lower environmental impact. Nevertheless, a strategic location of material suppliers and mixing plants could lower the transportation distances, improving its environmental performance. (AU)

• FAPESP's process: 17/25708-7 - Rheology and chemistry of asphalt binders and biobinders: tools to the comprehension of mechanical behavior, aging and deterioration of pavements
• Grantee: Kamilla Vasconcelos Savasini
• Support Opportunities: Research Grants - Young Investigators Grants