||Developing a Design Methodology and Quality-Control Measures to Use Reclaimed Asphalt Pavement in Unbound Base Aggregate in Flexible Pavements
Edward J. Hoppe
More than 90 percent of Virginia’s roads are built with hot-mix asphalt (HMA). A byproduct of their periodic reconstruction is asphalt millings, or reclaimed asphalt pavement (RAP).
Current limits on the percent of RAP that can be reincorporated into new hot mixes means more recycled material is accumulated than can be reused in these reconstruction operations. Thus, alternative uses are needed.
Recent VDOT research found that state transportation departments often consider RAP for pavement subbase and base courses. The Virginia Department of Transportation (VDOT) is considering blends of RAP with virgin aggregate in unbound aggregate base (UAB) layers.
This project will investigate the practical limits of RAP blends for UAB, while studying specific characteristics of aggregate sources and RAP stockpiles in Virginia. The researchers will identify appropriate quality-control methods to ensure proper construction in the field. They also will develop draft specifications for VDOT.