A new damage detection technique based on wave propagation for rails

摘要: Abstract This paper presents a novel damage detection technique, tailored at the identification of structural surface on rail structures. The detection, proposed in this paper, exploits wave propagation phenomena ( P , S Rayleigh and guided velocities) by identifying discrepancies, due to presence, dynamic behaviour structure. uncorrelations are generated waves reflected back sensor locations flaw surfaces. peculiarity presented approach is use time frequency coherence function for arrivals sensors methodology developed was divided into three steps. In first step, presence structure assessed. second arrival (or echo) estimated using continuous wavelet transform. Then, algorithm able, through ray-tracing algorithm, estimate location damage. A numerical investigation two single damages carried out. introduced railhead simulate rolling contact fatigue defects. results showed that can be used successfully localise location, however, as expected, localisation strongly affected range used. suggested separation characterisation modes crucial different types Further work needed establish severity relating magnitude changes reflection attenuation coefficients each selection best according type identified.