An investigation into rail corrugation evaluation based on fractal theory and explicit finite element method

Rail corrugation poses a persistent challenge in railway engineering, aggravating rolling contact fatigue and adversely affecting passenger comfort. However, the existing standards for rail grinding are inadequate for evaluating corrugation across multiple scales, underscoring the need for new evaluation indices. In this paper, we assess the effects of various characteristics of rail corrugation on the wheel-rail system and establish the relationship between the dynamic indices of the wheel-rail system and the fractal dimension of rail corrugation. Additionally, we derive the limit value of the fractal dimension of rail grinding based on the limit values of the dynamic indices. These findings provide a practical grinding guideline: when the sampling interval is 1 mm and the fractal dimension exceeds 1.252, rail grinding should be scheduled to mitigate dynamic overloads and extend service life.