A State-of-the-art Large-scale Laboratory Approach to Evaluating the Effectiveness of Geogrid Reinforcement in Flexible Pavements

Abstract

In this research, an Integrated Mobile Accelerated Test System (IMAS) was used to evaluate geogrids' reinforcement effects. The IMAS system consisted of a 5 ft diameter and 3 ft deep rigid box and an automatic loading frame to apply cyclic loads. A total of eight test configurations were constructed by varying geogrid types, geogrid locations in the base course, and base aggregate thicknesses. The IMAS performs cyclic load tests of pavement foundation sections to a large number of load cycles, which simulates vehicle-loading conditions expected during a pavement system's service life to evaluate the long-term performance of pavement structure. Testing results showed the effectiveness of geogrid reinforcement in the structural performance of pavements. Results show that biaxial and triaxial geogrids can decrease permanent deformation at the end of load cycles with an average value of 47 and 68 percent, respectively. Also, high-strength geogrids provide at least five psi pressure more than low-strength geogrids within the base course, which clarify that the high-strength geogrids can provide more confinement.