Impact of wheel shape on the vertical damage of cast crossing panels in turnouts

Impact forces generated in the load transfer area of railway crossing panels lead to a range of degradation modes from wear and fatigue of the contacting materials, fatigue of supporting components to ballast/subgrade deterioration. A simplified modelling approach has been developed to first analyse the geometrical problem of the axle rolling through the crossing geometry, and in a second step to predict the vertical dynamic force produce from the interaction between the wheel unsprung mass and the track system. The force is analysed in the frequency domain to estimate the level of damage in different parts of the track system. A parametric analysis of wheel shapes was carried out showing that the axle lateral displacement has a significant influence on the produced level of damage and also that characteristics such as the wheel flange thickness and the equivalent slope in the area of contact also leads to increased damage. It is suggested that such a measure in combination with the simplified algorithms developed here could be used, possibly in combination with track side monitoring system, to highlight traffic instances leading to increased asset damage.