Geogrid reinforcement has been extensively used over the past few decades to enhance the stability and load carrying capacity of different geomaterials. Understanding soil-geogrid interaction is essential for the analysis and design of geogrid-reinforced soil structures. A three-dimensional discrete element model that is capable of capturing the response of granular material with geogrid inclusion is developed in this study. The model is validated using experimental data and used to simulate a series of triaxial compression tests on reinforced granular material. The analysis allows for the explicit geometry of the geogrid and the discontinuous nature of the soil to be captured. The response of the geogrid-soil system is then investigated by examining the soil movement, inter-particle forces, and the stress distribution along the geogrid. In addition, the effects of the geogrid location within the soil, and the number of geogrid layers on the strength, stiffness, deformability of the specimen are evaluated. It is concluded that geogrid inclusion within soil samples can lead to significant increase in elastic modulus and the shear strength of the reinforced soil while reducing the permanent deformation under compression loading.

The calculated response confirms the observed behaviour of reinforced sands and explains the increase in load carrying capacity of reinforced systems used in different geotechnical engineering applications. The proposed modelling approach has proven efficient in modelling this class of problems and can be adapted for other reinforced soil applications.