Fatigue Evaluation of Railway Vehicle Bogie Frame by Different Methods

Abstract: The fatigue strength of a railway vehicle bogie frame is evaluated by different methods, which include endurance limit approach and cumulative damage approach. Haigh-Goodman and Smith-Goodman diagram in general standards are used in endurance limit approach, and four linear damage methods are considered in cumulative damage approach. During the evaluation, finite element method (FEM) and line test method are used to compare the two different evaluation approaches, while the line test dynamic stress is modified by mean stress calculated in FEM software. The comparison results illustrate that Haigh-Goodman and Smith-Goodman are identical when consider same safety factor, but the Goodman diagram in JIS standard are conservative relative to that in UIC standard. The elementary S-N curve is too conservative to reflect real situation, and the Haibach modified S-N curve are recommended when using cumulative damage approach