Experimental Investigation of Geogrid Reinforced Unpaved Sections Under Repeated Loads

Rutting has been one of the major pavement distresses that affect the performance and longevity of pavements constructed on weak or soft subgrades. Rutting is often associated with excessive deformation of the pavement layers under wheel loads, caused by layer densification and excessive vertical stress on the subgrade exceeding subgrade strength. Over the past two decades, geosynthetics have been used to reduce this excessive deformation by decreasing the vertical stresses on the subgrade. The primary objective of this study was to determine the effect of high-moduli geogrid-reinforced layers in reducing the vertical stresses on the subgrade. The current study addresses the objective by experimental investigation on reinforced pavement layers subjected to repeated loads. The experimental investigation involves conducting laboratory-based large-scale repeated load tests on geogrid-reinforced pavement sections constructed over weak subgrades. Based on the large-scale repeated load test results, it was observed that the geogrid-reinforced pavement sections reduced the vertical stress on the subgrade by 35–75% as compared to the unreinforced sections.