Field-based comparative environmental impact assessment of pavements considering steel slag for soil stabilisation

This is the authors' abstract. We don't add key points for this paper.

There is a need to reduce the amount of greenhouse gas emissions generated during material production for roadway applications. Research studies have shown great potential of the Kambara Reactor (KR) steel slag to stabilise soft soils in lieu of commercial binders. This study conducted a comparative life cycle assessment (LCA) on full-scale field sections currently in service, to see the environmental impact of slag use as soil stabiliser. Three pavement structures were investigated varying the base/subbase material: Pavement A, using KR slag and reclaimed asphalt pavement (RAP) recycled aggregates; and Pavements B and C, built with crushed natural aggregates. The LCA system boundaries extend from cradle-to-site, using three LCA methods, as well as the potential for circularity. Pavement A demonstrated the best overall environmental performance, achieving a reduction of at least 84,500 kg CO2 eq per kilometre compared to the other pavements. From all LCA methods, Pavement A presented lower impacts, except for one category, with a divergence between methods.