Influence cooling to 213 K for strength rail steel

The paper presents, the data indicating the need to take into account in the calculation of the strength of the railway track of changing the characteristics of the static strength of rail steel perlite class after its long operating time in the railway track with cooling to 213 K. It is shown that neglecting changes in the static strength characteristics of rail steel can significantly affect the performance railways and the safety of freight and passenger transportation. It is established that during the long operation of the rails in transit, the mechanical properties of the rail steel undergo significant changes. When cooling to 213 K of rail material, the values of the static strength characteristics of steel are reduced below the minimum value established by regulatory documents. On the basis of the experimental data, the permissible stresses for the rails material were calculated after long-term operation in transit for different temperatures and it was shown that it is necessary to take into account changes in the operation of the strength characteristics of rail steel when calculating the strength of railway tracks. Significant changes in the values of the characteristics of static strength and permissible stresses of rail steel at low temperatures can lead to a loss of bearing capacity of the rails. The obtained results confirm the need for carrying out extensive experimental studies of the effect of operational factors on the mechanical characteristics of rail steel