Comparison of gross tractive effort of a single grouser in two-dimensional DEM and experiment

In the development of DEM programs for interaction studies, 2D DEM analysis is often compared to the results of experiments done in 3D conditions. From an alternative viewpoint, a quasi-2D experiment was designed for this study to collect results of gross tractive effort and to examine the accuracy of 2D DEM applied to soil-grouser systems. To intensify the understanding and comparison of the grouser reaction and soil behavior, a soil model incorporating aluminum cylinders was used in the experiment instead of real soil. The particle size distribution of model soil was approximated by the combination of cylinders of two radii. The bulk density was set to be identical in DEM and the experiment. The normal spring constant and the coefficient of rolling friction in the contact model of DEM were adjusted using trial and error, considering the allowable time step, sinkage of the grouser, and the slope angle of the cavity behind the grouser. The developed 2D DEM program was confirmed to have sufficient capability to reproduce the experimentally obtained results of gross tractive effort with nine combinations of conditions of grouser height and grouser thickness.