Influence of Aggregate Thickness and Reinforcement Depth on Deformation Behavior of Geogrid-Reinforced Layer

Abstract

The deformation potential of geogrid-reinforced aggregate layer was investigated through laboratory large scale model tests. The influence of the aggregate layer thickness was mainly considered together with reinforcement depth. Cyclic pressures were applied with increasing the amplitude after every 500 cycles. Under low pressure amplitude, the rate of surface deformation reached a stable stage with increasing load cycles, regardless of reinforcement condition. This rate was more progressive with load cycles under high pressure amplitude, which was more obvious in unreinforced case. Surface deformation was considerably resulted from lateral flow in thick aggregate layer, and from subgrade deformation in case of thin aggregate layer, especially for the reinforced case. The contribution of subgrade deformation was small on surface deformation in thick aggregate layer, while it was significant in thin layer. The effective reinforcement condition was achieved when geogrid was placed at the middle of layer.