Feasibility assessment of guided wave generation in rail using electromagnetic acoustic transducers for in-service inspection

This study investigates the use of electromagnetic acoustic transducers to generate and detect ultrasonic guided waves from the rail head for in-service rail inspection. Unlike conventional bulk wave methods using rolling search units, this approach aims to overcome limitations like limited coverage, need for contact, and high noise. A pitch-catch configuration is analyzed, with a transmitter and receiver placed at a realistic distance on the rail head. Due to hardware constraints, a specific excitation frequency had to be used in the experiments; numerical simulations were therefore employed to verify the presence of suitable wave modes in its vicinity. Experimental tests then validate the wave propagation in both healthy and artificially defected rails, assessing detectability and the influence of sleeper positioning. Signal comparisons between defect-free and defective cases aim to identify features indicative of structural anomalies.