ABSTRACT
Deformation behavior of geogrid-reinforced aggregate layer was investigated through laboratory model tests. Unpaved road was modelled by using silica sand and aggregate. Cyclic loading tests were performed, considering the effects of aggregate thickness and pressure intensities. Aggregate thickness had minimal influence on surface settlement, except under 550 kPa pressure. However, this was significant on the sand layer settlement since under 200 kPa. Sand layer settlement highly contributed to surface settlement in 10 cm thick aggregate layer under all pressure levels. This contribution became small with increase in aggregate thickness. However, loss of aggregate thickness increased with increase in thickness. This loss was reduced with the inclusion of geogrid, especially when geogrid was inside 20 cm thick aggregate layer. With geogrid inclusion, surface settlement was reduced in the respective cases, by 45% in 10 cm, and 25% in 20 cm thicknesses.
