Life Cycle Assessment (LCA) is a tool that can be used to identify the environmental impact of a product or process. This paper compares three different replacement options for an aging portland cement concrete (PCC) pavement using LCA process-based protocol. Those options are: remove and replace with PCC pavement, remove and replace with hot mix asphalt (HMA) pavement, and crack-and-seat the existing pavement followed by a HMA overlay. Each option investigated includes a detailed construction and rehabilitationschedule and is analyzed over 50 years. Results show that materials production (e.g., cement, asphalt, PCC, HMA) dominates the energy use, emissions and impacts for all three options. In general, HMA production tends to cause the HMA option to have the highest energy use while cement productiontends to cause the PCC option to have the highest global warming potential (GWP). Of significant note, the crack, seat and overlay option was the lowest energy and GWP option and produced the least emissions in more measured categories than the other two options. In the future this may become astrong argument for expansion of the crack, seat and overlay method of rehabilitation.
Samenvatting