Abstract:

Take 295/80R22.5 as the research object, a new frictional model, modified attenuation index frictional model, is proposed based on the Coulomb frictional model and the attenuation index model. The nonlinear friction least squares method is used to establish the new friction model. The tread deformation law by numerical analysis method is investigated, and the relationship between the tread deformation and the distribution of the stiffness and the road holding performance are revealed. The results show that the modified friction model can reflect the change of braking force between tire and road surface more realistically. The radial deformation is largest in the center and gradually decreases from center to edge area. The longitudinal deformation is larger at the leading edge of the contact area, and smaller at the trailing end. Increasing the vertical deformation is conducive to the improvement of grip performance. The micro radial stiffness values in the middle contact area (except the edge area) changes not so much, and two extreme values appear on both sides of the tire shoulder. The micro longitudinal stiffness value in the shoulder area is obviously lower than that in the middle, and it is symmetrical about the center line of the tread. Reducing the radial and longitudinal micro-stiffness increases the grip force.

Key words: grip force, stiffness matrix, tread deformation, friction model