After studies have been promoted for a few decades to establish its theoretical basis, continuum damage mechanics is now being applied to engineering issues, as an effective modeling method to evaluate the damage, fatigue and life of materials. Before applying the method, it is needed to determine some material constants which characterize the damage and fatigue behaviors of the material in question. In this study, the material constants of the rail steel used for the JIS50kgN rail were determined based on the stress-strain curve and S-N curve. It was shown using these constants that numerical analyses were able to successfully reproduce these curves. As a simple application of the method, the fatigue life of a bar made of the rail steel under a repeated three-point bending condition was predicted and compared with the life obtained experimentally. The good agreement of the values of life span obtained through analysis and experiments showed that the analysis based on the damage mechanics was one of the useful methods for prediction of rail life.

Copyright (c) 2003 Railway Technical Research Institute