Three-Dimensional Modeling of Geogrid Pullout Test Using Finite-Element Method

Abstract

Three-dimensional (3D) modeling of soil–geogrid interaction is a numerical challenge when simulating reinforced soil systems. Modeling the soil–geogrid interaction requires an appropriate consideration of the geogrid geometry, the materials’ model, and the interface properties. In this study, a series of 3D models were developed using the finite-element method (FEM) to investigate the response of geogrid under confined and unconfined conditions focusing on geogrid tensile stiffness effects. In this regard, a modeling approach for the geogrids whose configuration is complex was proposed. The validity of the models was also justified by the good agreement between calculated numerical results and measured experimental data. Moreover, particular emphasis was placed on visualizing the soil–geogrid interaction and load transfer mechanisms. The load transfer mechanisms were embodied not only through the distributions of displacement, strain, and tensile force along the geogrid but also through the displacement fields inside the soil domain. The results from two series of tests showed that the proposed approach was capable of reasonably capturing the geogrid response, whether under unconfined or soil-confined conditions.