ABSTRACT

The use of geogrid products to stabilize flexible pavement systems has been well documented, particularly for paved and unpaved roads over soft subgrades. However, the quantification of the benefit of incorporating the geogrids requires further investigation. The objective of this study was to compare the performance of different flexible pavement sections with and without geogrid reinforcement to attempt to quantify the potential benefit of the geogrid inclusion in terms of extended service life and reduced pavement structure. To achieve this objective, full-scale test sections were constructed including unstabilized and stabilized test items with different pavement structures. Standard construction equipment and methods were used to build the model pavement section and replicate field conditions. Each individual test item was trafficked with a Heavy Vehicle Simulator (HVS) equipped with a dual-wheel tandem axle gear loaded to 20,000 lbs and a tire pressure of 120 psi. This paper describes the testing and the analysis of the rutting performance of the different test items. The results demonstrate that the inclusion of the geogrid products provides enhanced rutting resistance compared to unstabilized sections. In addition, the performance comparison also demonstrates that the inclusion of geogrid reinforcement within the base course can allow a reduction in the base course thickness, and/or in some cases, the asphalt concrete surface thickness.