Investigation on reverse detail fracture in high rails on curved tracks

This thesis investigates the cause of reverse transverse defects (RTDs) found in high rails on curved tracks. A parametric study on the role of bending stress on RTD initiation has been investigated using a finite element model. Reverse bending stresses have been found to be inadequate to initiate a crack at the rail lower gauge corner. Microstructural examinations of flow lips of ex-service high rails from curved tracks have been conducted along the transverse and longitudinal rail sections. Cracks have originated from the brittle white etching layer and at the flow lip caused by uneven plastic flow of material.