Evaluating Stabilizing Effects of Geosynthetics in Flexible Airport Pavement Structures by FE Analyses

Geosynthetic reinforcements have demonstrated their effectiveness in enhancing road pavement structures through mechanical stabilization. However, airport pavements possess distinctive characteristics, including higher pressure loads, thicker pavement layers, and the need for longer lasting and reliable surfaces due to restrictive operational requirements. Therefore, it is crucial to understand whether geosynthetics products can provide structural enhanced performance within airport pavements. To investigate this, finite element (FE) models were developed to assess the impact of geosynthetic reinforcements in flexible airport pavements subjected to cyclic aircraft loading. These models were calibrated using data from instrumented large-scale experimental prototypes conducted by Robinson and Norwood in 2019. A parametric study revealed that the inclusion of a geosynthetic at different positions could effectively reduce strains in the airport pavement. The optimal location for geosynthetic placement was identified at the subbase—subgrade interface. Furthermore, this study emphasizes the significant impact of multi-layer reinforcements, which was evident in the expanded region influenced by the stabilizing effect of the geosynthetic reinforcement. Permanent and dynamic displacements, as well as elongation deformations, showed significant advantages with the use of a multi-layer reinforcement system, demonstrating reduced permanent displacements by 24%, dynamic displacements by 16%, and elongation deformation by 18% compared to an unreinforced pavement.