Durability assessment of railway car axles taking into account the character of the stress spectrum

In many countries, railway cars with axles that have operated for over 50 years are still in use, which significantly exceeds their normative service life. This can be explained by the fact that design calculations are based on overestimated loads, as evidenced by published information on diagnostics of railway axles, which is performed under real operating conditions. In this work proposes a method for calculating the durability of axles of railway cars under real operating conditions, which is based on fatigue tests of samples made of axle material, the statistical theory of similarity of fatigue failure, analysis of the stress state and known models of fatigue curves. The calculations performed showed that, under real operating conditions, the durability of the axles exceeds N=1010 cycles, which indicates their operation in the field of gigacycle fatigue. These values N correspond to a service life of over 30 years. Recommendations are given for assessing the durability of railway axles, taking into account actual operating conditions.