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Railway rolling stock spring suspension elastic–friction elements can be connected in parallel or in series–parallel. Wedge-type dampers can also be applied in spring suspension. These dampers friction force is created due to the elastic force of the additional (wedge) spring and depends on its deformation. In all these types of elements connection, the vibrational energy decreases because of dissipation by the friction damper and the force characteristic changes. The force characteristic of the friction damper has the appearance of a rectangle, the vertical sides of which correspond to the moments of the sign of the derivative and, therefore, the moment of transition from the positive to the negative direction of the friction force. It is shown that if the dynamic force developed in the suspension is less than the friction force, the friction damper wedges the suspension and the total dynamic movement of the upper point of the suspension becomes equal to the disturbance. The obtained expressions for determining the forces and deformations in elastic–friction elements allow one to perform calculations of rolling stock vibrations with such elements of spring suspension.

The model of interaction between the wheel of a locomotive and a rail based on taking into account the discrete structure of solid deformable bodies using the fundamental concept of metal lattice dislocations was developed. Under the action of applied normal and tangential forces, these dislocations can move and exit to the surface of the crystal or part, if, for example, the Mises yield criterion is fulfilled, which can be considered as a condition for the emergence of dislocations on the surface. The creep force is treated as the total force of destruction of the grippers between the groups of atoms of the wheel and the rail, and simultaneously, the occurring process of sliding the wheel along the rail—as a process of “collapse” of dislocations emerging on the contact surface, i.e., as a translational plastic flow (shear without deformation). It was shown that the creep force depends on the normal and tangential pressures of the wheel on the rail, as well as on a number of additional factors, such as an increase in the number of dislocations with an increase in the deformation rate of the contact zone and the coefficient of destruction of the oxide film. The satisfactory convergence of the results of calculations of lateral fluctuations of the locomotive obtained with the use of the proposed model and known experimental data is shown.