Research on Wheel Fatigue Test of Railway Vehicles Based on Non-contact Full-field Strain Measurement Technology

Abstract

Wheel is one of the most important component in the running part of railway vehicle, and its fatigue performance directly affects the running quality and safety of the vehicle. When carrying out wheel fatigue test, the maximum radial test stress amplitude applied on wheel spoke is 240Mpa according to EN13262. The wheel-axle model is meshed by Hypermesh, and then finite element analysis is carried out by Ansys to obtain the required test load and the maximum radial stress position. The required load is input into the wheel-axle fatigue test system, and speckle is sprayed at the maximum radial stress area of the spoke plate. The actual stress value measured by non-contact full-field strain measurement technology based on 3D-DIC (digital image correlation) have good repeatability with the stress value measured by strain gauges applied at the maximum radial stress of the spoke plate, and full-field stress-strain nephogram of the concerned region can be obtained. Compared with conventional measurement methods, non-contact full-field strain measurement technology has the advantages of high accuracy, fast response, wide measurement range, small temperature effect and low environmental requirements. The application of noncontact full-field strain measurement technology can realize the closed-loop control of the load in key area during the process of design, analysis and test of wheel, and improve the accuracy and efficiency of the test.