Life cycle assessment of pavement construction: A case study

Abstract Road construction is often associated with carbon emissions from direct and indirect sources, primarily due to construction and maintenance activities. Currently, there is a lack of comprehensive Life Cycle Assessment (LCA) benchmarks to evaluate flexible composite pavement, fully flexible pavement and pavement rehabilitation options under various ground conditions. The objective of this study is to investigate the environmental impact associated with different pavement designs over a 60-year analysis period, comprising a 40-year basic design period with maintenance extended up to 60 years. This research paper encompasses a literature review on pavement LCA and conducts and LCA on various pavement design and construction options, following the ISO 14040 framework and PAS 2080 methodology. The LCA in this study specifically focuses on material production, transportation, construction, maintenance, and end-of-life phases. Using global warming potential as an environmental indicator, the study calculates and compares a range of potential impacts for each component. In terms of carbon emissions, the rehabilitation option was found to be most favourable when compared to other full-depth reconstruction options, while the flexible composite pavement option exhibited the highest carbon emission value compared to other pavement build-ups assessed. Additionally, a sensitivity analysis was conducted to identify ‘hotspots’ in the study, which increase the confidence level of the results.