Discrete element method (DEM) simulation of single grouser shoe-soil interaction at varied moisture contents

The soil-tool interaction can effectively be modeled with discrete element method (DEM) when a proper contact model and DEM parameters are applied. The interaction of a single grouser shoe with clay loam terrain at varying moisture content was simulated using the discrete element approach. The study was consisted of three soil moisture contents which were dry (7.5%), moist (21.5%), and wet (38%) by dry weight basis with a single grouser shoe model with three grouser heights 60, 55, and 45 mm respectively. The simulation was performed by using EDEM 2018 software, and the contact model was Hertz Mindlin. The DEM parameters were calibrated for each moisture content after trials, and to validate the DEM simulation, soil-bin experiments were carried out. The DEM model has captured the actual conditions of soil particle collection and transportation. The maximum tractive force was generated at the interface of 45 mm height grouser with moist (21.5%) soil level. The simulation and experimental results were compared to determine the accuracy of the contact model. The minimum error (10.09%) was found for moist soil with 45 mm grouser height between simulated and experimental results. It was concluded that the developed DEM model is substantial and can be used to analyze the soil-track contact mechanism and the true shear condition between the single grouser shoe and the soil at higher moisture contents were obtained by DEM simulation.