Project Details

In this research study, mixtures prepared using three WMA technologies - Sasobit®, Advera® WMA and The Foamer were evaluated for volumetric properties, moisture susceptibility and permanent deformation in comparison with a control HMA mixture. Tensile Strength Ratio (TSR) and Asphalt Pavement Analyzer (APA) tests were done to characterize these mixtures. Dynamic Modulus test was conducted on specimens at 7 percent air voids in wet and dry conditions to determine the E* stiffness ratio (ESR) to validate TSR test results and to assess moisture damage sensitivity of the mixes. Dynamic modulus of mix at 4 percent air voids was also measured and used as input in the Mechanistic-Empirical Pavement Design Guide (M-E PDG) to predict pavement performance with respect to fatigue cracking and rutting. The predicted pavement performance data was used to conduct a cost-benefit analysis of use of WMA technology in asphalt concrete surface course construction. Evaluation of long-term performance of WMA mixtures using materials locally available in North Carolina will help NCDOT engineers in identifying the best WMA technology and provide performance data that can be used to design asphalt concrete pavements using WMA.