Mechanistic empirical performance of warm-mix asphalt with select bio-derived additives in the Midwestern United States using AASHTOWare pavement ME design

Abstract

An industry-wide emphasis on sustainable asphalt practices has given rise to increasing use of warm-mix asphalt (WMA) technologies. WMA reduces both binder viscosity and mixing and compaction temperatures by 20–55°C during the asphalt mix production and laydown process. This research investigates several bio-derived WMA additives that act as chemical modifiers with surfactant properties. Two established additives derived from the forest products industry are studied as well as a WMA additive in development that is derived from corn. The objective of this research is to use the new AASHTOWare Pavement ME Design to compare the established forest product WMA additives with the new WMA corn-derived additive that is in development. Using binder and mix test results as input values in AASHTOWare Pavement ME Design, predicted pavement performance was evaluated for sensitivity to different climatic conditions seen in the Midwestern United States. Results indicate that the climatic conditions have a larger impact on the pavement performance as compared to the impact from binder type and additive choice. The corn-derived WMA additive was similar to the other established WMA additives and HMA control group showing similar pavement performance predicted by the AASHTOWare Pavement ME Design.