Transverse Crack Propagation Characteristics of Rail Bottom under Wheel-Rail Force

Abstract

The finite element model of multi-span continuous beam track is established to research the stress and strain fields of rail under the wheel-rail force. On this basis, according to the practical observation of crack shape, a three-dimensional semi-elliptical crack model was established, the singular element method was employed to simulate the stress field singularity of crack tip, and the transverse crack propagation characteristics of rail bottom under wheel-rail force was studied. The results show that: with the increase of wheel-rail force (vertical, lateral and longitudinal force), KI shows an increasing trend, and with the increase of lateral force, the increase rate of KI is maximum; with the increase of vertical force, both of the KII and KIII show a decreasing trend. However, with the increase of lateral and longitudinal force, both of them show an increasing trend. From the range of stress strength factor of crack tip, the amplitude of KI at the crack tip of rail outer edge is maximum , but the crack tip amplitude of KII and KIII is maximum at partial to the rail centerline.