Abstract
Effectiveness of geogrids in flexible pavement reinforcement was investigated throughout laboratory testing and finite-element analysis (FEA). The laboratory testing involved routine material characterization, resilient modulus testing, and five pavement prototype sections. These sections consisted of a 5 cm asphalt concrete (AC) layer, 15 cm granular base layer, and a 30 cm clay subgrade. The base layer was reinforced with a single layer of uniaxial geogrid placed at four different positions within the base layer. The pavement sections were loaded with a static plate-loading equipment and the results were compared with the control section (CS), which had no reinforcement. Results from this study showed that geogrids can be used to reduce tensile stresses in flexible pavement systems. The optimum position of the geogrid reinforcement to reduce tensile strains was found to be directly underneath the AC layer then within 33-50% of the granular base layer height as measured from the bottom of the base layer.