A Large Test Box Study on Geocell-Reinforced Recycled Asphalt Pavement (RAP) Bases over Weak Subgrade under Cyclic Loading

Abstract

Currently, great emphasis is placed on sustainable construction and infrastructure with green technologies. As a result, the demand for sustainable and environmental friendly roads is increasing day by day. More technologies for sustainable roadway construction are needed. One way to construct environmentally sound roads is through the use of recycled asphalt pavement (RAP) materials as a base course. However, limited research has been done to quantify its structural capacity with engineering properties. It is expected that RAP base courses may have excessive deformation under traffic loading due to the existence of asphalt in RAP. It is believed that geocell confinement can reduce the permanent deformation and improve the performance of RAP bases. In this study, three-dimensional novel polymeric alloy (NPA) geocell was used to confine RAP bases. To investigate the effect of geocell confinement on the performance of road bases, unreinforced and geocell-reinforced RAP bases were constructed over weak subgrade (target California bearing ratio of 2%) in a large geotechnical test box (2 m x 2.2 m x 2 m high) and tested under cyclic loading. The test results showed that geocell confinement reduced the permanent deformation and vertical stress distribution at the interface between base and subgrade, and increased percentage of elastic deformation as compared with the unreinforced base.