Use of Biaxial Geogrid for Reinforcement in Flexible Pavement

Abstract: Reinforcement of flexible pavements using geo-synthetics—particularly geogrids—has become a widely adopted technique to address the increasing demands on road infrastructure due to growing traffic loads and environmental challenges. This approach enhances the mechanical behavior of pavement systems by improving load distribution, reducing stresses transferred to the subgrade, and minimizing surface deformation such as rutting and cracking. The incorporation of geo-synthetic reinforcement contributes to increased pavement longevity, improved structural integrity, and reduced construction and maintenance costs.
This study presents a comprehensive examination of the design principles, influencing factors, and performance outcomes associated with reinforced flexible pavements. Key parameters such as geogrid stiffness, aperture size, placement depth, subgrade strength, and the thickness of the pavement layers are explored to understand their roles in overall pavement performance. A synthesis of experimental laboratory investigations provides the foundation for developing a regression- based model aimed at predicting the Granular Equivalent (GE) factor. This factor quantifies the reinforcement’s contribution to pavement strength, enabling engineers to adjust layer thicknesses without compromising performance. The proposed model is grounded in the AASHTO 1993 pavement design methodology and is validated through back- analysis of a wide range of laboratory test data.