A comparative environmental impact analysis of asphalt mixtures containing crumb rubber and reclaimed asphalt pavement using life cycle assessment

ABSTRACT

Recently, the reduction of the environmental burdens related to highway infrastructures has been in the spotlight. Within this context, the use of recycled materials in bituminous mixtures for road pavement construction and maintenance has the potential to mitigate the excessive use of non-renewable resources. Nevertheless, the material consumption is only one of the aspects that affects the sustainability of an infrastructure. Other relevant aspects related to environmental issues should be considered. The objective of this work is to evaluate the potential environmental impacts of asphalt mixtures containing crumb rubber (CR) (vulcanised or devulcanised) and reclaimed asphalt pavement (RAP) assuming different Degree of binder Activation (DoA) of the aged binder by means of a life cycle assessment (LCA). The results show that the small amount of CR used for bituminous mixtures application does not justify all the additional consumption of resources and emissions associated with its treatment. These results are explained by the higher environmental impacts stemming from the treatment of the rubber and the higher amount of bitumen employed in the mixture. In turn, for mixtures containing RAP the analysis revealed an improvement in the score of all the environmental indicators considered.

KEYWORDS:

• Life cycle assessment
• crumb rubber
• devulcanisation
• RAP
• base course
• road sustainable materials

Acknowledgements

The third author is supported by the Ministry of Education, Science and Technological Development of the Republic of Serbia through the research project TR 36017 “Utilization of by-products and recycled waste materials in concrete composites in the scope of sustainable construction development in Serbia: investigation and environmental assessment of possible applications” and this support is gratefully acknowledged.

Disclosure statement

No potential conflict of interest was reported by the authors.

Correction Statement

This article has been republished with minor changes. These changes do not impact the academic content of the article.