Simulation of Sandy Soil Shear Characteristics: Calibration and Validation of DEM Contact Models

Abstract

: In this study, the behavior of sandy soil has been comprehensively investigated through the application of the Discrete Element Method (DEM) in various moisture and density conditions. Three distinct contact models, including Hertz-Mindlin (HM), Hysteretic Spring (HS), and Hertz-Mindlin with JKR (HM+JKR), have been meticulously evaluated for their performance in replicating the intricate interactions and mechanical responses observed in sandy soil particles under different loading conditions. Laboratory Direct Shear Tests (DSTs) were conducted to obtain empirical data, and the simulation results were subsequently compared with these experimental findings to validate the models. The HM model exhibited notable efficacy in simulating dry soil conditions, while the HS model excelled in capturing the behavior of moist soil, and the HM+JKR model demonstrated superior performance in representing wet soil conditions. The relative errors between simulated and measured yield forces remained within acceptable limits across all models, affirming their reliability in characterizing soil behavior. These calibrated models will prove invaluable in future simulations and analyses of soil-tool interactions in agriculture and geotechnical engineering applications. This research has significantly contributed to a deeper understanding of the Discrete Element Method's capabilities in modeling soil mechanics and has offered valuable insights into the selection of appropriate contact models tailored to distinct soil conditions.