Sustainable Stabilization of Recycled Asphalt Pavement (RAP) Bases

Abstract

When flexible pavements reach the end of their service life, they are often rehabilitated by removing existing hot mix asphalt (HMA) surfaces and replacing the removed portion with new HMA or concrete. A large amount of recycled asphalt pavement (RAP) materials are created every year during the rehabilitation and reconstruction of existing flexible pavements. Due to the existence of asphalt, 100% RAP typically has low stiffness and high creep and permanent deformation potentials under traffic loading, which are the concerns in the use of RAP as a base course. The use of RAP for pavement construction by itself is a sustainable option, and more sustainability can be obtained by increasing the life of such pavements. Geocell, a three-dimensional geosynthetic product, has been proposed by the authors to stabilize RAP bases. A series of medium-scale static plate loading tests and large-scale cyclic plate loading tests were conducted on unstabilized and geocell-stabilized RAP bases to investigate their stiffness and creep and permanent deformations. The test results showed that geocell significantly reduced the creep and permanent deformations of the RAP bases and increased the resilient deformation and stiffness of the RAP bases. Therefore, 100% RAP can be used as a base course material with geocell confinement as a sustainable roadway construction technology.