Nondestructive Characterization of Temperature Dependent Tension in Track Rail

An ultrasonic method is proposed to determine the level of pre-tension in rails of the high speed test-track. The specific ultrasonic approach has the benefits of being able to perform measurements without the need to account for the texture in the sample and can be used on structures with irregular geometries. The ultrasonic technique can also be used to establish the temperature dependent changes of the pre-tension in the rails. From these measurements, an accurate assessment of the pre-tension levels in the rails can be determined. The result of the proposed research program will be a field portable inspection system based on a portable computer that can be operated remotely by a single user. This will provide the means for the pre-tension levels to be determined rapidly and the data to be stored for later analysis. The results obtained from this instrument will enable the modeling of the state of pre-tension in the rails and provide recommendations for the necessary repair procedures to restore the rail to its design specifications. Preliminary contacts with commercial users have demonstrated a significant interest in this proposed system, simplifying the commercialization process.