Description

Large quantities of waste generated in the municipal, commercial and industrial and construction and demolition sectors have caused widespread environmental issues. The replacement of virgin materials with recycled in pavement construction is a possible solution for waste management and achieving sustainability goals in the infrastructure sector. There are, however, questions about environmental and economic impacts of waste-derived materials in road construction that need to be answered. Life cycle assessment and life cycle cost analysis are two approaches to quantify and assess the environmental performance and the costs of decisions regarding the selection of materials for pavement construction. While considerable research has been conducted on pavement materials, the impacts of particular materials such as recycled concrete aggregates, lignin, waste plastic, recycled glass, crushed brick and crumb rubber are not currently well understood. This research presents a synthesis of the state of the art of selected recycled materials in pavement construction and limitations of existing environmental and economic analysis. A major interest towards recycling of materials and necessity of their sustainability analysis is highlighted. The results indicate that the sustainability analysis of selected recycled materials is in its infancy with considerable inconsistencies, hindering the meaningful comparison of results. Furthermore, exclusion of impacts of maintenance, usage and end of life phases from sustainability analysis, impose uncertainty on the long-term viability of these materials. Further research is needed to develop better understanding of these impacts so that more informed decisions could be made by policy makers.