Experimental investigation of the stabilization performance trends of two geogrids constructed on low bearing capacity subgrade

Experiments were carried out on real size samples in the laboratory to investigate the geogrid stabilization performance in highway pavement applications. A moving wheel load was applied on representative pavement samples constructed on low bearing capacity subgrade with and without geogrids. Two types of geogrids were used to construct the pavement sample configurations. Resistance to plastic (permanent) deformation was recorded as a performance indicator to compare structural performance trends of the pavement samples. For this objective, surface deformations were measured after certain wheel load repetitions. Rut depths were calculated from surface profiles measured with a laser profiler. Layer thicknesses were varied to observe differences in the deformation trends. When appropriate conditions were reached in the trial configurations, all layer thicknesses were kept constant during the tests. The two geogrid types constructed with the same granular materials and varying layer thicknesses were used in different layer interfaces to search for the most optimum solution. According to the study findings, the use of geogrid over soft subgrade with low CBR values has been shown to extend the life of the pavement by reducing the rut depth.