Comparing environmental impacts of alternative roads: Mechanical and sustainable considerations

In recent years, sustainability and “green” issues have gained increasing attention. When considering the environmental impacts of transport infrastructures, road pavements prove to have a major environmental impact, due to huge resource consumption (both materials and fuels), emissions, consequences on the ecosystems, etc. Consequently, researchers, governments and industries have focused on developing methods for evaluating the sustainability of the different technological solutions for ensuring sustainable development. In this paper, different pavement solutions (including warm mixing technologies, WMA) have been considered and their performance evaluated in terms of both mechanical efficiency and sustainability. First, based on selected traffic and environmental conditions, mechanically equivalent pavements were designed, and then a Life Cycle Assessment (LCA), including production and construction phases, was performed. The numerical results proved that WMA, although it may ensure a reduction in mixing temperature, and thus in fuel consumptions during production, determines related environmental impacts and emissions that are still very marked as a consequence of the need for specific additives (i.e. zeolite) involved in this technology.