Centrifuge modeling on the geosynthetic-reinforced soil (GRS) abutments with different combinations of reinforcement spacing and tensile stiffness

Three centrifuge model tests were conducted to investigate the performance of geosynthetic reinforced soil (GRS) abutments with modular block facing under localized vertical loads. This study examined the effects of different combinations of reinforcement spacing S_v and tensile stiffness J on the behavior of GRS abutments. In this study, river sand and woven geotextiles were used as the backfill soil and reinforcement material, respectively. Test results show that under the same ratio of J/S_v = 3.7, using the combination of smaller S_v and lower J was more effective in minimizing the beam seat settlements and the lateral facing displacements induced by localized vertical loads than the combination of larger S_v and higher J. Meanwhile, smaller additional vertical stresses transferred from the applied loads within the GRS abutment and smaller reinforcement tensile forces were also observed for the combination of smaller S_v and lower J. Furthermore, the maximum tensile forces in each layer occurred under the beam seat for the upper reinforcement layers and near the facing for the lower layers for all three tests. A more uniform distribution of the reinforcement tensile force was found for the combination of smaller S_v and lower J.