Contact Stress Analysis in Wheel–Rail by Hertzian Method and Finite Element Method

Abstract

Safety and economy of railway traffic is enormously influenced by the contact stress variation caused by wheel rail contact profile changes. A change in designed surface topology may result from wear that brings in a wide change in contact geometry and stresses. To study the influence of interacting wheel and rail profile topology of standard rail UIC60, the standard wheel profile as per Indian Railway standards are considered in this paper. Rail profile radii, wheel profile radii and wheel profile taper are chosen for six different values. The analytical formulation is based on Timoshenko’s approach and Finite Element Method (FEM) based simulation of the problems is undertaken. With these tools, distribution of contact zones, contact stress and contact pressure for different configuration of the wheel and rail profiles are obtained. The mesh density in contact region is found to have a direct influence on the accuracy of the solution [1]. To standardize the analysis of the contact region, mesh with an element size of 1 mm for all the configurations are chosen. Using stress response obtained through FEM analysis and multiaxial fatigue crack initiation model, the effects of vertical loading on fatigue crack initiation life are investigated. This may allow a direct design application for railways in particular.