Greenhouse Gas Emissions Reduction Opportunities for Concrete Pavements

Concrete pavements are a vital par t of the transpor tation infrastructure, comprising nearly 25% of the interstate network in the United States. With transpor tation authorities and industry organizations increasingly seeking out methods to reduce their carbon footprint, there is a need to identify and quantitatively evaluate the greenhouse gas (GHG) emission reduction oppor tunities that exist in the concrete pavement life cycle. A select few of these oppor tunities are explored in this ar ticle in order to represent possible reduction approaches and their associated cost-effectiveness: reducing embodied emissions by increasing fly ash content and by avoiding overdesign; increasing albedo by using white aggregates; increasing carbonation by temporarily stockpiling recycled concrete aggregates; and reducing vehicle fuel consumption by adding an extra rehabilitation. These reduction strategies are evaluated for interstate, ar terial, collector, and local road designs under urban and rural scenarios. The results indicate that significant GHG emission reductions are possible, with over half of the scenarios resulting in 10% reductions, compared to unimproved baseline designs. Given the right conditions, each scenario has the potential to reduce GHG emissions at costs comparable to the current price of carbon.