Harnessing guided waves for long-range monitoring of damaged rails

We experimentally unveil the monitoring capabilities of guided waves in the context of railways engineering when operating in a harsh environment. To this end, the integrity of damaged rails is probed by way of resonant and nonresonant transduction mechanisms based on piezoelectric sensing and actuation. The experimental analysis is accomplished through the selective excitation and measurement of guided wave modes propagating through the rail, which are herein used to qualify: (i) the maximum distance reachable through the elastic signal; (ii) their capability of detecting damages. We show that guided waves are excellent candidates to detect modified dynamic behaviors inherently linked to forthcoming failures and are naturally applicable in the context of railway engineering where the environment plays a critical role in the wear of structural components.