A Simple Binder Specification Tweak to Promote Best Performers

摘要

SuperPave™ is the most sophisticated specification system for asphalt binder acceptance for use in pavements. The system was developed and validated for straight-run, refinery-produced asphalts available in the 1980s, and it has been implemented in the United States and Canada throughout the 1990s. However, increased performance demands, economic and environmental pressures have led to increased use of modified grades, reclaimed asphalt pavement, and a variety of "softeners" although not all have manifested in adequate long-term performance in the field. It was demonstrated that the current SuperPave parameter, |G*| sin δ, cannot prevent acceptance of some lower-quality materials and a different approach is necessary to prevent premature binder aging and pavement cracking. The current paper shows that the Dynamic Shear Rheometer (DSR) test performed on Pressure Aging Vessel (PAV) residue can be simply modified to exclude phase incompatible binders from passing the specification, without the need for development of the new test method. The approach proposed can also be applied to historical data and allow for inexpensive field validation on past and current pavement test sections. This approach takes advantage of features already available in SuperPave, allows for fast implementation with no additional testing and validation cost, or product certification time and product supply cost.