DEM simulation of stress transmission under agricultural traffic Part 2:Shear stress at the tyre-soil interface

Although it has been proven to be of considerable importance, it remains unclear how to model the effect of traction on soil compaction. This study used multiple approaches to simulate the stress under an active wheel with the pseudo-continuous Söhne model, and compared it to a discrete element method (DEM) model of the same scenario. It was found that the differences in normal horizontal stress (σy) due to these different boundary conditions in the Söhne model were limited. According to these simulations, the effect on normal vertical stress (σz) was negligible. This was in contrast with the DEM simulations, where the impact of traction on σy was also stronger and less shallow. Advanced numerical models can be used to gain insight in the importance of traction, and could be used to improve the boundary condition of the Söhne model. However, further experimental validation is needed.