Abstract
The subject of dynamic tests is a prototype wagon for transporting semi-trailers with a load of total weight of up to 400kN. This wagon was originally equipped with a standard Y25 bogie, which could be used at a speed of 100km/h with a standard load. Currently, this type of bogies can be used, in some load cases, even at speeds of 120km/h. Therefore, an attempt was made to numerically verify the possibility of using such a bogie in a special wagon for transporting semi-trailers under permissible load conditions and at increased travel speed. The paper presents the methodology of numerical tests of the dynamics of a freight wagon and the problems of selecting suspension parameters in Y25 bogies of railway wagons moving at speeds of 100km/h and 120km/h on straight and curved tracks. For this purpose, numerical methods and wagon motion simulations were used, with the example of a prototype wagon with a rotating loading platform. Therefore, the construction of an innovative railway wagon was discussed with a description of characteristic design features and the results of the tests of damped free vibrations of the wagon with or without load and the influence of the change in the damping of the bogie suspension on the forces acting in wheel-rail contact in railway bogies when the wagon moves on the straight and curved track at speeds of 100km/h and 120km/h. The tests of changes in the value of wheel contact forces on the rail in both wagon bogies on the front and rear axles of the wagon allowed to formulate the motion stability criterion of the vehicle without load and with maximum load. Numerical analyses confirm that Y25 damping influences wheel–rail forces, allowing stable motion at 100km/h, while at 120km/h curved sections may generate increased wheel loads.