## 5 Conclusions and Recommendations  
The conducted studies and obtained results allow the following main conclusions and recommendations to be formulated:  
1. A study of the vibrations of a wagon moving along an inertial elastic-viscous track was carried out in a linear formulation; dynamic additions to the forces in the spring suspension sets, interaction forces, rail deflections, and bending moments in the rails were analyzed in both moving and stationary coordinate systems. It was established that the influence of the neighboring wheelset affects the interaction forces and bending moments (by approximately 10%) and, to a greater extent, the rail deflections (up to 20%). This conclusion holds true for the speed range of 60-180 km/h and disturbances with spectral frequencies up to 20 Hz. 2. Existing methods and new approaches for representing the rail as a system with concentrated parameters were considered and developed. For this purpose, the frequency characteristic of the studied system is represented as the product of two blocks, one of which defines the output signal at the same section where the force is applied, while the other depends on the spatial coordinate. The real and imaginary frequency characteristics of both blocks were constructed, and their approximation by polynomials was carried out using the least squares method within a frequency range exceeding the natural frequencies of the wagon vibrations. 3. The frequency characteristic of the block determining the output signal at the same section where the force is applied can, in the first approximation, be represented by a second-degree polynomial; the coefficients of this polynomial correspond to the reduced mass, stiffness, and coefficient of viscous friction. 4. It was established that, at the existing wagon speeds, the reduced parameters of the track can be determined from the frequency characteristic of the track obtained under a stationary force. 5. Numerical values of the reduced track parameters in the vertical and horizontal planes were determined. 6. The developed method for representing the rail as a system with concentrated parameters allowed for this study of the planar vibrations of a wagon moving along an inertial elastoviscous track, taking into account the influence of the neighboring wheelset in the nonlinear formulation. When accounting for Coulomb friction dampers in the wagon's suspension, the forces acting on the body and wheelsets were found to be larger than those with viscous friction dampers. 7. When solving the problem in the nonlinear formulation, the influence of the neighboring wheelset affects the forces arising in the suspension spring assemblies of the body to a greater extent (up to 21%). 8. An overestimated value of friction in the track leads to a significant reduction in all forces (in the suspension--up to 19%; interaction forces--up to 31%) at high speeds. 9. It was established that the inertial properties of the track must be taken into account when studying the vibrations of wagons, especially in the nonlinear formulation. The forces in the suspension for a non-inertial track are 6% larger, and the interaction forces are 8% larger compared to the inertial track with viscous friction dampers, and 8% and 96% larger, respectively, with Coulomb friction dampers. 10. The results obtained through the roller stand simulations at varying speeds of the freight car model show that the suspension spring assemblies of the truck hardly move. The body vibrations, occurring due to its elastic properties, have a frequency of 6-7 Hz. Due to the small magnitude of static deflection and insufficient damping of the vibrations, the amplitude of the accelerations increases with speed, while the vibrations gradually decay. **Author Contributions:** Study conception and design, V.G.S. and N.M.M. ; data collection, A.A.M. and S.T.A. ; analysis and interpretation of results, N.V.I. and J.S.M. ; draft manuscript preparation, G.T.Y. All authors have read and agreed to the published version of the manuscript.