A Method based on Pseudo Excitation Method to Analyze Random Dynamic Stress of Railway Vehicle System

Random dynamic stress of a railway vehicle caused by track irregularity need to be calculated accurately in order to predict the railway vehicle’s fatigue life. It is usually described as the function of mileage. Since the traditional analysis method of this issue is complicated and very time consuming, in this paper, an efficient approach based on Pseudo Excitation Method (PEM) and Finite Element Model (FEM) is developed. By using the proposed approach, the stress power spectral density (PSD) of the railway vehicle contains some specific structures can be calculated conveniently, the related statistical parameters of the coupled vehicletrack system can be obtained accurately as well. The reliability of the proposed approach is verified by comparing with a field test, in which the stress of the front and the rear traction beam of a metro car body is measured. It was proved that the simulation results of the proposed method are in good agreement with the test results, both on the value of magnitude and distribution trend, the relative error of the stress Root Mean Square (RMS) is less than 20% in general, mostly within 10%.