Study on establishment of standardized load spectrum on bogie frames of high-speed trains

Abstract

Establishing a structural load spectrum under actual operating conditions is a major problem in structural fatigue life analysis. This study introduces a load measuring method for the bogie frame structure. The quasi-static load-measuring frame can measure different load systems synchronously. The t test method is employed to evaluate the least test time to deduce the parent distribution. In order to fit the load spectrum distribution accurately, the kernel density estimation method is employed, which is based on the sample characteristics. The expansion factor method is used to deduce the maximum load. The formula for a standardized load spectrum is derived from the deduced maximum load, the linear factor between operating condition length and cumulative frequency, and the parent distribution of each load system. The damage consistency criterion is performed by solving the objective function with constraint conditions. The calibrated damage provides a suitable representation of the real damage under actual operating conditions. By processing and analyzing the load and stress spectral data of the measured lines, it is verified that the standardized load spectrum established in this paper is superior to the European specification and the Japanese specification in evaluating the fatigue reliability of the structure.