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The article deals with considerations regarding the geometric filtering effect of the bounce and pitch movements derived from a railway vehicle movement on a track with irregularities. The cases in which the geometric filtering effect of the bounce and pitch movements in a bogie are presented and so is for a bogie-based vehicle, plus the corresponding filtering frequencies. The characteristics of the geometric filtering of the symmetrical and antisymmetrical movements of bounce and pitch are examined for the plans of axles in a vehicle. The analysis of the geometric filtering effect influence upon the behavior of vertical vibrations proves the selective nature of the geometric filtering depending on the velocity, the position along the carbody and the vehicle natural vibration modes. [ABSTRACT FROM AUTHOR]

The paper herein presents a new model of the interaction between an unbalanced wheel and rail. Acceleration of the wheel and the wheel/rail contact force are the most important parameters depending on the wheel unbalance. In fact, the two parameters increase strongly when the velocity is higher than 200 km/h. Because of that, the mass of the running gear of the high speed trains has to be low and the wheels unbalance has to be rigorously limited. [ABSTRACT FROM AUTHOR]

The railway vehicles are characterized by the fact that the wheel axle moves in the path of travel and self guidance in the contact forces between the tire rim and wheel tracks. Following wheels, besides the three common features they have and other land vehicles, namely support vehicle vertically, running about and propulsion, respectively braking railway vehicles in addition their specific function, namely self guidance that the two wires inside of rail. Being metallic wheels and also the rails that give the vehicle the ability to rail loadings much higher than other land vehicles. This capability, combined with that of self guidance, creates the possibility of forming convoys of vehicles (trains) heavy, giving wheel system - advantages of high capacity rail transport. The study and thorough understanding of the complex phenomena of the contact wheel - rail is actually the fundamental problem that ensures the development of railway vehicles. [ABSTRACT FROM AUTHOR]

Lateral oscillation of railway vehicles is a major problem for narrow gauge railways or metric because reduced diameter bogie wheels. This problem can be reduced by changing the Prud'homme limit on vehicles and improving resistance tread lateral, being able to use the checkrails. Running with lateral oscillations road of the railway vehicles passenger and freight is a known problem for standard gauge railways. The lateral movement represents a particular problem which causes passengers discomfort and in major cases, the operating speed must be reduced. Whilst the railways and trains may suffer because of this. A possibility to resolve these problems should as reducing the Prud'homme limit, which defines the permissible lateral load, repeated exerted on the rail. This formula was used for vehicles and standard gauge railways, but many companies and suppliers of rolling stock have assumed that can be applied on narrow gauge lines. On the basis of existing information, without being made field tests or computer simulations, Prud'homme limit can be modified to standard gauge rail networks, but to verify the load lateral of this type of gauge must be made more investigations. Inevitably have emerged more simplistic assumptions, but is unlikely to significantly alter the conclusions. [ABSTRACT FROM AUTHOR]