Performance evaluation of full-scale geosynthetic reinforced flexible pavement

Abstract

An accelerated wheel load testing program was conducted to evaluate the benefits of using geosynthetics to enhance the performance of pavement constructed over soft subgrade. Six full-scale test sections were constructed, among which two sections were reinforced by one or two layers of triaxial geogrids, and two sections were reinforced by one layer of high strength geotextile with different base layer thickness. The test sections were instrumented by a variety of sensors to measure the load- and environment-associated pavement response and performance. The results of full-scale accelerated load testing demonstrate the benefits of using geosynthetics in terms of reducing the permanent deformation in the pavement structure. The geosynthetics benefit to reducing the maximum stress on top of subgrade is more distinguishable at a higher load level. It was also found that the geosynthetic placed at the base-subgrade interface was able to improve the performance of both subgrade and base layers. By placing an additional layer of geogrid at the upper one-third of the base layer, the performance of the base layer was further enhanced. While the geosynthetic showed appreciable benefit to reducing the permanent deformation of subgrade in this study, it showed little effect on the resilient properties of subgrade.