Development of Superpave 5 asphalt mix designs for Minnesota pavements
Principal Investigator(s):Mihai Marasteanu, Professor, Civil, Environmental and Geo-Engineering
- Jialiang Le, Associate Professor, Civil, Environmental and Geo-Engineering
Recent studies have shown that the air void ratio of hot mix asphalt (HMA) has a significant effect on the durability and long-term performance of asphalt pavements. The Minnesota Department of Transportation (MnDOT) HMA pavements are typically constructed with air voids close to 7 percent in the mat and often exceeding 10 percent over the longitudinal construction joints. Recent efforts in Indiana have shown that a new mix design method, called Superpave 5, can be used to design mixtures at 5 percent air voids and to successfully compact them in the field at the same 5 percent air voids, a significant decrease compared to current practice. According to a study performed for the Washington State Department of Transportation, each 1 percent increase in air voids results in about 10 percent loss in pavement service life. Recently published data indicate that the Superpave 5 pavement sections built in Indiana are performing very well. Please note that the Indiana Department of Transportation pays for the compacted asphalt mix in place as one pay item.
The objective is to build upon the preliminary results of a current project, in which the compaction process of HMA is investigated through a combined experimental and computational approach and develop Superpave 5 mix designs for various traffic levels using local aggregates specific to Minnesota projects. It is expected that at the end of the project, new mix designs will be proposed for Level 3 and Level 5 Superpave mixtures.