State of the Practice for High Polymer-Modified Asphalt Binders and Mixtures

Abstract

The objective of this paper was to provide information on the state of the practice for using high polymer-modified (HP) asphalt concrete (AC) mixtures in the United States (U.S.) and Canada. This information was collected through a survey of U.S. and Canadian provincial agencies combined with a search of HP-related specifications, special provisions, and field trials or pilot projects previously constructed. Moreover, the Virginia Department of Transportation’s (VDOT) current state of the practice with regard to using HP paving material was determined. This was achieved through a navigation of VDOT databases to report tonnage and types of produced HP AC mixtures, and experience, lessons learned, and best practices on behalf of multiple asphalt contractors in the area. The majority of the agencies that currently use or have constructed field trials and pilot projects using HP AC mixtures are located in the eastern part of the U.S. In general, HP AC mixtures have been used in a wide range of applications ranging from full-depth AC to thin AC overlays under heavy traffic on interstates and slow-braking loads at intersections. No major field-related construction issues in relation to mixing temperatures and in-place compaction of HP AC mixtures were reported, and standard construction practices and equipment were used. Finally, good communication between the polymer/binder supplier and the contractor, and solid planning before conducting the work were important lessons learned with regard to paving with HP AC mixtures.