Investigation of probable squat growth from initial surface cracks in rails using a three-dimensional rollover simulation

Abstract

Squats are rather complex failure mechanisms in rails and challenge railway operators all over the world, thus calling for a detailed investigation of squats by means of finite element analysis to locate the initiation and propagating mechanisms. In this work, a cyclic three-dimensional (3D) finite element model of a wheel-rail contact including an initial penny-shaped defect is used. This work presents the implementation of the starting penny-shaped crack in the rail for a wheel-rail simulation by utilising a submodel strategy. Moreover, viable evaluation options are shown. In the future, this set-up will help to assess multiple crack positions and possible squat growth mechanisms.

Experimental and Numerical Visualisation of Subsurface Rail Deformation in a Full-Scale Wheel–Rail Test Rig

“…This approach allows continuous rollover simulations without lifting the wheel from the rail, as the wheel rolls over the entire length of the rail and is then mapped back to the starting position [27]. A schematic of the simulation model is shown in Figure 5 (adapted from Gschwandl et al [28]).…”