Propagation lifetime of railway axles: experiments and probabilistic approach

Inspection intervals of critical safety components should be calculated on the basis of very sophisticated crack growth algorithms able to describe crack propagation under service loads. The present paper deals with the application of NASGRO crack growth algorithm to estimation of propagation lifetime in a mild steel widely used in railway axles. The analysis of experimental crack growth and threshold data has enabled to propose two random variable models for estimation of propagation lifetimes, discussing their statistical properties and their implications for lifetime estimates.