This paper discusses the possibilities of mitigation of the rolling noise in the railway vehicles by means of the rail dampers. In this context, the generation mechanism for this type of noise is therefore described. The active techniques and methods of control over the rolling noise, focused on the track infrastructure and the rolling stock are enumerated. The highlight is the rail damper from the perspective of its practical implementation and the review of the most important results concerning the reduction of the rolling noise in many European countries. The conclusions validate the difficulty found in a correct evaluation of the efficiency in the rail dampers and of their effect upon the track infrastructurerequirements for costly investments.

The paper investigates the effects of mechanical wheel slide protection devices (WSPD) on the braking capacity for coaches equipped with disc or cast iron block brakes. Decelerations and jerks, that affect the passengers comfort, are also analyzed. An original simulation program, based on experimentally determined air pressure evolutions in brake cylinder is used for this purpose. Results of numerical simulations show that in the case of repeated actuations of mechanical WSPDs, disc brake vehicles are more affected in terms of braking capacity. Regarding jerks during braking actions, in both normal and low adhesion conditions, vehicles equipped with high power cast iron block brake with two pressure levels prove to be more affected.

The paper analyzes the effect of the vertical track irregularities upon the vibrations in a two-axle bogie. The method in use implies the bogie modelling and the measurement of the vibrations in wheelsets generated by the track vertical irregularities. The behaviour of vibrations in the bogie is evaluated via the results derived from applications of numerical simulation developed on the basis of the bogie model, where the inputs are the accelerations measured in the two wheelsets. The vibration features in the bogie are pointed out at according to the spectra of accelerations in the bogie frame, to the standard deviation values of accelerations and to the maximum values of the accelerations calculated against the two wheelsets.

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