Experimental Analysis of Rail Contact Fatigue Damage on Frog Rail of Fixed Common Crossing 1:12

Abstract

Assembled fixed common crossings of the steel grade R350HT with high switch angles are subjected to quick rail contact fatigue (RCF) deterioration. The crossings are a significant cost driver in railway maintenance and have an important influence on reliability and availability in railway transportation. The present paper is devoted to the experimental study of the deterioration causes that is based on inertial and geometrical measurements on one crossing during its full lifecycle. The causes are classified into primary technical ones and secondary ones, which depend on the operational work and maintenance of track and rolling stock. The primary causes are studied using analyses of the impact position and inertial measurements on the frog nose during the crossing lifecycle, the end of which is marked by RCF defects. An application of the machine learning technique t-distributed stochastic neighbor embedding (t-SNE) allowed to determine a small cluster of high-impact loadings that correspond to the future damage zone location. The appearance of the high-impact loadings group on a certain location is explained by the secondary causes: rail and wheel wear and wheel lateral position. A multivariate kinematic modeling of wheel passages from wing to frog rail provided the wheel trajectories, impact position, and trajectory kink angle in the impact point. The distribution of the calculated impact angles along the frog rail demonstrated the presence of a small cluster of high-impact angles outside of the zone subjected to the highest number of impacts. The results of the geometrical measurements correspond to those obtained by the acceleration measurements.