Element Tests Investigating Reinforcement Strain Distribution of Geosynthetic-Reinforced Soil (GRS) Mass Under Vertical Loading

The Geosynthetic-Reinforced Soil (GRS) abutments have the advantages eliminating deferential settlements between the bridge beam and the approaching embankment and reducing the construction costs and difficulties. In recent years, more and more GRS abutments have been constructed throughout the world but the deformation characteristics of the GRS abutments have not been completely understood and further studies need to be carried out. This study conducted 13 two-dimensional element tests to investigate the effects of backfill gradation, reinforcement spacing Sv, and reinforcement strength Tf on the reinforcement strain distribution of the GRS mass under vertical stage loading. Dry silicon sand with three different gradations was used as backfill soil and two biaxial polypropylene geogrids with different ultimate tensile strength were used as reinforcement material. The results showed that the geogrid strain increased with the increase of the backfill strength and modulus, the decrease of the reinforcement spacing, and the increase of the reinforcement strength under the same vertical load. The geogrid strain increased from the edge of the GRS mass to the center and the maximum geogrid strain of all geogrid layers occurred at the mid-height of the GRS mass.