Gaps, challenges and possible solution for prediction of wheel–rail rolling contact fatigue crack initiation

The prediction of wheel/rail rolling contact fatigue (RCF) crack initiation during railway operations is an important task. Since RCF crack evolution is influenced by many factors, its prediction process is complex. This paper reviews the existing approaches to predict RCF crack initiation. The crack initiation region is predicted by the shakedown map. By combining the shakedown map with various initiation criteria and the critical plane method, the crack initiation life is calculated. The classification, methodologies, theories and applications of these approaches are included in this paper. The advantages and limitations of these methods are analyzed to provide recommendation for RCF crack initiation prediction. This review highlights that wheel/rail dynamic characteristic, complex working conditions, surface defects and wear all affect the RCF crack initiation. The optimal selection of criteria is essential in the crack initiation prediction. Based on the research gap regarding the challenging process of crack initiation prediction detailed in this review, a proposed prediction process of RCF crack initiation is proposed to achieve a more accurate result.