“Roller-Compacted Concrete Overlay on Asphalt:
A U.S. Case Study on Design, Construction, and Performance”
Authors: Victor Cervantes, Feng Mu, Corey Zollinger, and James Johnston
Presented at the 97th Annual Transportation Research Board (TRB) Meeting in Washington, D.C. held January 7-11, 2018.
Roller Compacted Concrete (RCC) paving has been around for more than four decades and has been effectively used in ports, intermodal yards and industrial applications. More recently, RCC paving has transitioned into streets and roads.
This report focuses on the design, placement, and performance of an RCC overlay on an existing asphalt surface. Pavement design software, that was developed for conventional concrete, was employed and adapted to design the unbounded RCC overlay. The final design called for an 8-in. (200-mm) RCC overlay on the existing pavement. Two mix designs with different aggregate gradation were used on the project to compare their reaction to the paver & roller compaction. The RCC was mixed in a continuous pugmill and placed with a high-density asphalt paver. High density 97-98% was typically achieved after the paver and a roller were used to increase the wet density where needed. A curing compound was then sprayed over the wet concrete followed by an early entry saw that was used to create two slab sizes, i.e. 12 ft x 12 ft (3.6 m x 3.6 m) and 12 ft x 15 ft (3.6 m x 4.5 m) in order to investigate their difference.
After two years of service, the pavement is performing well and little distress has been observed. Although the pavement has been performing well, there is still room for improvement mainly in three areas:
- First, it is recommended that a design tool be developed specifically for optimizing RCC, especially RCC overlay, designs.
- Second, more research is needed on RCC mix design taking into account various aggregate characteristics.
- Lastly, there is an opportunity to make RCC overlays more economical by investigating the potential of bonding RCC overlay to the existing pavement.
For this abstract and links to the full paper on the TRB website, please go to: https://trid.trb.org/view/1495624
To purchase the full paper from the TRB website, please go to: http://amonline.trb.org/2017trb-1.3983622/t004-1.4001281/541-1.4001432/18-03127-1.3995912/18-03127-1.4001437?qr=1
HOME PAGE PHOTO: RCC Pavement Council:
45th Street Reconstruction, Bel Aire, Kansas, USA
**Project won the American Concrete Paving Association Gold Award 2014