Comparative analysis of FEM tire-soft snow interaction and theoretical model based on Bekker’s coefficients

Abstract

Tire-deformable terrain interaction is a complex phenomenon that has proven difficult to characterize accurately and comprehensively using numerical models. While researchers have attempted to develop various numerical models to estimate tire behavior on deformable terrain, the most accurate models to date rely on empirical data and are only applicable to specific rolling conditions. In this research paper, a comparison between theoretical mechanics and a finite element method (FEM) model of a rigid tire rolling on a layer of soft snow is presented. The goal is to compare the data obtained from the FEM tire-soft snow interaction analysis with the data generated by a theoretical numerical model. The FEM snow model is developed using the Drucker-Prager cap material model while the tire is assumed rigid. The assumption of the rigid tire can provide reasonably accurate results in the case of the soft snow interaction model. The theoretical pressure-sinkage coefficients of the Bekker equation (kc, kϕ and n) for soft snow are calculated by simulating vertical penetration tests in the FEM snow model. The results of the pressure distribution and rolling resistance due to compaction obtained by the FEM and the theoretical model results are then compared.