The influence of geogrid aperture size on the behavior of reinforced granular bases

Geogrid-reinforcement of a granular base provides confinement to aggregates and mobilizes their intrinsic capacity. The interaction between the geogrid and the aggregates is highly governed by the relative size of the aggregates and the geogrid aperture. Experimental studies showed the performance of the geogrid-reinforced base dependent on the ratio of the aggregate diameter to the aperture size. Numerical investigations of geogrid-reinforced bases were conducted in this study to understand this mechanism at a micro-level. Commercial software, Particle Flow Code (PFC)-2D based on the Discrete Element Method (DEM), was used for this purpose. Base courses consisting of uniform aggregates reinforced with the geogrids of different aperture sizes were subjected to a 10 kN cyclic ramp load at a frequency of 0.76 Hz. The numerical results showed the effect of the geogrid aperture size on the performance of the base course.