Experimental and 3-D finite element analyses on geocell-reinforced embankments

This article presents an improvement in performance that is due to the inclusion of geocell in the embankment base overlying a soft foundation bed. Firstly, model tests were conducted on embankments over soft clay, in which a mattress of geocell reinforcement was placed at the interface between the embankment and soft foundation bed, which was trimmed at the embankment's toe. Parameters like type of infill material and aspect ratio (pocket-size) of the geocell layer were varied during the experimental program to observe their effects on the performance of geocell-reinforced embankments. A model test on unreinforced embankment was also carried out to show influence on performance and improvement as a result of the presence of geocell reinforcement. A significant percentage of decrease in vertical settlements, lateral deformations, and heaving-with a percentage of increase in the load-bearing capacity of embankments reinforced with geocell-were observed from the test results, as compared to unreinforced embankments. The experimental results were validated using three-dimensional finite element analyses of geocell-reinforced embankments. The results of the finite element method (FEM) showed good agreement with that of the model tests. The displacement and vertical stress distributions of geocell-reinforced embankment were also studied using FEM. Lastly, a parametric study was carried out to observe the influence of the stiffness of subgrade soil, tensile strength of geocell material, stiffness of infill material, effective friction angle of infill material, and effective cohesion of embankment soil on the performance of geocell-reinforced embankment base.