A parametric study on the fatigue life of turnout crossings using the finite element approach

Abstract

Railway turnouts (switches and crossings) are important elements in the railway infrastructure that provide flexibility of the system and guide the railway traffic. However, due to the high impact forces, severe damage to the turnout crossing can frequently be observed. In this paper parametric studies are performed to investigate the effects of different railpads, friction coefficients and traveling directions on the dynamic behaviour of the turnout crossing. First, the dynamic behaviour is analysed using the explicit finite element method accounting for non-linear material properties (plasticity) of the rails. From the numerical simulations the dynamic responses such as contact forces, stress and strain distribution in rails, sleepers and ballast are obtained. After that on the basis of the obtained responses rail fatigue analysis is performed. A critical plane and energy density based fatigue analysis approach is used to assess the crossing performance under various conditions of the parametric studies. The performance is estimated by predicted fatigue life to crack initiation in the crossing rail. The results of these parametric studies are presented and discussed.