Experimental Modal Analysis and Modelling of an Agricultural Tire

Traction properties of agricultural tires on deformable grounds are strongly dependent on the interaction between tread elements with the soil, which is in turn function of parameters like tread design and inflating pressure. The present paper presents a numerical model aimed at investigating tire performance and soil compaction under different conditions, considering effects due to tangential and normal compliance of the terrain surface as well as tread design and inflating pressure. In particular, the ground has been modelled as a deformable springs layer and the tire as a flexible ring reproducing the tread geometry. Longitudinal and vertical dynamics of the tire are taken into account. Moreover, effect of tire carcass deformation was included considering the in-plane eigenmodes of the tire identified through a series of experimental tests.