The use of asphalt rubber in the rehabilitation of flexible and rigid pavement systems has been shown to improve the performance of these systems and extend their service life. This has been demonstrated in the laboratory, field, and using analytical tools such as finite element method (FEM).
The California Department of Transportation (Caltrans) has been implementing reduced thickness design standards of asphalt rubber overlays since 1992. These standards call for a reduction in the thickness of the overlay when rubberized hot mix asphalt is used in lieu of conventional hot mix asphalt.
This paper explores the background and basis behind the reduced thickness design concepts and further provides validation to this approach. Additionally, this paper will discuss the benefits of using various asphalt rubber strategies in lieu of using conventional asphalt.