Simulation of dynamic gauge widening and rail roll: effects on derailment and rolling contact fatigue

Abstract

This paper compares the different effects of rail rotations versus rail lateral translations on wheel/rail (W/R) contact geometry and vehicle dynamic performance. This study, conducted by the Transportation Technology Center, Inc. (TTCI), shows that: rail rotation has significant effects on the W/R contact geometry, especially on contact positions and contact areas, while rail translation effects on wheel contact positions and contact areas are negligible; a W/R contact model with assumptions of rigid track or elastic track with only lateral and vertical rail translations cannot reflect the W/R contact geometry variations caused by rail rotations; the contact geometry variations caused by rail rotations strongly depend on the specific wheel and rail profiles under evaluation; proper rail rotation flexibilities within the safety limits could improve wheelset steering performance and decrease W/R contact stress and wear.