Dynamic Measurement of Contact Positions Between Wheels and Rails Using Surface Waves

Abstract Information on the contact positions between train wheels and rails while running through curves is essential for evaluating new wheel and rail profiles, investigating wear and damage, and analyzing the sources and mechanisms of wheel–rail noise. The objective of this study was to dynamically measure wheel–rail contact positions using surface waves. Measurement tests were conducted using a full-scale test machine, test track, and train. The reflection position of the surface waves corresponded to the edge of the wheel–rail contact area, indicating the usefulness of surface waves as a method for measuring the wheel–rail contact position. Additionally, the study showed that the distinct positioning characteristics for the leading and trailing axles of the bogie as well as the two-point contact near the gauge corner of the high rail, can be evaluated based on actual measurements.