Research on load characteristics of high-speed train bogie frame with inner axle-box based on measurement data

Purpose The purpose of this article is to comprehensively investigate the load characteristics of the high-speed train bogie frame with inner axle-box and analyze the applicability of the EN 13749 standard. Design/methodology/approach This article studies the load characteristics and the maximum load extrapolation approach for the high-speed train bogie frame with inner axle-box. The bench calibration experiments and field line measurements are carried out. Findings The measured variable-amplitude loads are converted to an equivalent constant-amplitude load and compared against the standard limit values, which are found to be below the specified limits. The response frequencies of the three loads show a correlation with respect to changes in velocity. The maximum load amplitude responses of both transverse damper loads and antisnaking damper loads are concentrated around 1.5 Hz. Axle-box traction link loads are primarily concentrated within the 0–50 Hz frequency range. Compared with the extrapolation results of polynomial regression, the errors of locally weighted least squares regression (LWLS) are all below 5%, validating the feasibility of this method for load extrapolation of bogie frame with inner axle-box. Originality/value Based on axle-box traction link load data and bogie load analysis, the equations for rhombic loads and traction loads are established. Weighted least squares reflects the differences in the data used by varying the weights assigned to the fitting parameters. This work provides reasonable guidance for future research and optimization of the high-speed train bogie frame with inner axle-box.