Fatigue life assessment of high-speed train’s bogie frame due to dynamic loads under the influence of wheel flat

A bogie frame is the most important railway vehicle’s component that supports almost the weight of the system, and it is subjected to various excitations and loads that can result in the failure of the structure. The dynamic forces influenced by various excitations, both internal and external, can speed up the system's fatigue failure. This paper aims to analyse the impact of wheel flats on the life of a high-speed bogie frame. To accomplish this study, a Chinese railway high-speed (CRH2) bogie frame, has been chosen for the analysis. The required input data for CRH2 have been collected from literature; the wheel flat defect models under the wheel flat lengths of 20 mm, 40 mm, and 60 mm have been developed with a MATLAB tool, and the results have been inputted into a multibody model with the SIMPACK tool. The dynamic response loads for each case have been exported and applied to the finite element model in ANSYS, where stresses and strain have been used to estimate the fatigue life. The results from the study show that as the wheel flat length increases, it increases the dynamic forces and stresses that decrease the life of the bogie frame; thus, the influence of wheel flat should be considered in the life prediction of a bogie frame.