Study on Photoelastic Imaging Technology of Ultrasonic Guided Wave in Rails for High Speed Railway

摘要

Ultrasonic guided wave inspection is considered to delect flaw effectively in rails for high-speed railway and simultaneously it can be used for SHM(structure health monitor), the propagation process of ultrasonic in the railway turnout is complex. In order to make the guided waves become visible and people can observe complicated Ultrasonic field directly, according to the Maxwell law of stress-optic refraction, polarized light interference method is employed for establishing the dynamic photoelastic imaging system, and the bottom of the switch rail and rail waist variable cross-section optical test block with K9 optical glass material are designed and produced. Choosing different probes, research of different probes to excite guided wave in the test block in the sound field is carried on. Using CCD shooting test block, guided wave sound field images through the computer software are taken for acquisition and analysis. The sound field visualization is implemented, which can be used to guide ultrasonic guided wave inspection in practice.