Comparative Assessment of Geocell and Geogrid Reinforcement for Flexible Pavement: Numerical Parametric Study

Development of highways and railways play crucial role in a nation’s economic growth. While rigid concrete pavements are durable with high load bearing characteristics, growing economies mostly rely on flexible pavements which enables easier and economical construction. The strength of flexible pavement is based on the strength of subgrade and load distribution characteristics of intermediate granular layers. In this scenario, to simultaneously meet economy and strength criteria, it is imperative to strengthen and stabilize the load-transferring layers, namely subbase, and base. Geosynthetic reinforcement in planar and cellular forms has been proven effective in improving soil stiffness and providing a stable load transfer platform. The present study investigates the efficiency of geocells over single/multiple layer geogrid reinforcements by a series of three-dimensional model analyses of a flexible pavement section under a standard repetitive wheel load. The geocell network modeled with actual curvature is assumed to be embedded in the granular base with hard contact without separation. Stress transfer mechanisms and deformation profiles under various reinforcement configurations are also studied. Geocell reinforcement is observed to take up a higher proportion of stress caused by the traffic loads compared to single and double-layer geogrid reinforcements. The efficiency of single geogrid reinforcement reduces with an increase in embedment depth. The contribution of lower geogrid is insignificant in the case of the double-geogrid reinforced system.