Evaluation of new pavement technologies in Nevada

Abstract

The performance of the PG-graded binders with Hveem mixtures throughout Nevada indicated that in the majority of the cases the Superpave PG grading system alone is not fully capable of accurately identifying the potential performance of polymer-modified binders under Nevada's traffic, materials, and environmental conditions. On several cases the PG grading system indicated that a potential problem may arise from the use of the polymer-modified binder in the Hot Mix Asphalt (HMA) mixture while field performance proved otherwise. In light of the field performance data that have been developed on the use of PG grading system with Hveem mixtures, it is recommended that any implementation of the Superpave PG grading system in Nevada should be accompanied with specific requirements on the use of polymer modification process. These requirements can be in terms of dictating the percent and/or type of polymer to be used. Recognizing that the Superpave PG grading system was originally developed for neat asphalt binders, this approach will allow the Nevada Department of Transportation to implement the Superpave PG grading while other research efforts are being conducted to make it more compatible with polymer-modified binders.