Operation of the rolling stock is associated with a number of risks. The consequences of failures are sometimes very serious - safety or the environment, sometimes only economic. A significant factor affecting the safe operation of railway vehicles is maintenance. The paper presents methods of risks assessment and possibilities of their reduction in design, operation and maintenance of railway vehicles. Special attention is given to the new "silent brakes" and safety related issues for freight wagons.

MATEC Web of Conferences, open access proceedings in Materials science, Engineering and Chemistry

This paper presents environmental acute problems from increasing noise levels caused by automobile and rail transport. Noise barriers are considered to be an effective element in reducing noise in densely populated urban areas. However, do these barriers have the correct height, shape, material design, and construction? In the materials and methods, the basic characteristics of noise barrier, sound absorption, and sound insulation are described. Further, measurement methods of the insertion loss of outdoor noise barriers of all types using the direct and indirect method according to standard ISO 10847 and the Adrienne method according to standards EN 1793-5 and EN 1793-6 are presented. The measurement results of insertion loss of the selected noise barrier obtained by the indirect method showed a value of 19.1 dB(A) of insertion loss. This result was compared with simulation by our own software based on the CNOSSOS methodology, giving value of 19.6 dB(A), which is a good correlation. The Adrienne method was used for determination of the airborne sound insulation index of another noise barrier, giving a value of the single-number rating of the sound insulation of the barrier of 28 dB. In discussion, according to EN 1793-2, this value assigns an insulation index of category D3, which means that the barrier is high quality and has satisfactory airborne sound insulation. The advantages and disadvantages of both methods according to STN ISO 10847 and STN EN 1793-6 were discussed. We concluded that the main advantage of the method Adrienne—TN EN 1793-6 is that it can be used in situ under direct sound field conditions and can directly evaluate the sound insulation index of the whole barrier structure.

Noise generated by railway wagons in operation is produced by large numbers of noise sources. Although the railway transport is considered to be environmental friendly, especially in production of CO₂ emissions, noise is one of problems that should be solved to keep the railway transport competitive and sustainable in future. In the EU, there is a strong permanent legislation pressure on interior and exterior noise reduction in railway transport. In the last years in Slovakia, besides modernization of existing passenger wagons fleet as a cheaper option of transport quality improvement, quite a number of coaches have been newly manufactured, too. The new design is usually aimed at increased speed, higher travel comfort, in which reduction of noise levels is expected. However, not always the new designs meet all expectations. Noise generation and propagation is a complex system and should be treated such from the beginning. There are possibilities to simulate the structural natural frequencies to predict vibrations and sound generated by these vibrations. However, the real picture about sound fields can be obtained only by practical measurements. Simulations of the wagon’s natural frequencies and mode shapes and measurements in real operation using a digital acoustic camera Soundcam have been done, which showed that for the calculated speeds the largest share of noise from the chassis was not radiated through the floor of the wagon, as was expected, but through the ceiling of the wagon. To improve the acoustic properties of the wagon at higher speed, it was proposed to use high-volume textile insulation in the ceiling of the wagon. The paper briefly presents modern research approaches in the search for ways to reduce internal noise in selected wagons used in normal operation on the Slovak railways.