Fatigue damage assessment of high-speed train bogie frame load spectra based on phase reconstruction

Abstract

This study is focused on the issue of fatigue failure in the bogie frame during high-speed train operation, and is aimed to accurately predicting the fatigue life of the frame using measured load data. To minimize the discrepancy between the damage calculated by the load spectrum and the measured damage, a load phase matrix reconstruction method is proposed in this paper. The load-strain transfer matrix and load-stress transfer matrix are derived through calibration of the frame and auxiliary equipment, while the load and stress time history is obtained by track test. The correlation between the key stress measurement points in various load systems, as well as the relationship between the stress and load, are analyzed. Furthermore, a load prediction stress model is established using a phase matrix by reconstructing the load phase information lost during rain-flow counting through bench loading tests. The error between the calculated equivalent stress and the measured equivalent stress indicates that the load spectrum that incorporates a phase matrix more closely resembles the actual fatigue damage than the load spectrum without a phase matrix.