Guided Lamb Wave Propagation in Embedded Piezoelectric Transducer Networks for Structural Health Monitoring of Steel Bridge Girders

This study investigates guided Lamb wave propagation in piezoelectric transducer networks for detection and localization of fatigue cracks in steel bridge girders within the context of structural engineering and non-destructive evaluation, an area of growing scientific importance given its implications for in-service bridge structural health monitoring to supplement visual inspection and extend inspection intervals. Using embedded piezoelectric transducer network with pitch-catch Lamb wave pulse transmission and sparse reconstruction damage imaging, we examine fatigue crack presence scattering and attenuating transmitted Lamb wave modes detectable as amplitude reduction and phase delay in received signals in 6 steel W18x97 girder specimens (each 4 m long) with fatigue crack sizes from 0 to 60 mm drawn from structural laboratory fatigue test frame with environmental chamber simulating 0-50 C temperature cycling. Results indicate that the optimized 12-transducer network configuration detects cracks as small as 8 mm in W-section girder flanges with 94.2% detection accuracy and localization error less than 12 mm using S0 mode at 250 kHz (p < 0.001), with 94.2% detection accuracy for 8-mm cracks as the primary quantitative benchmark. Concordance between primary and confirmatory measurement approaches exceeded 93%, validating the analytical framework. These findings contribute empirically to structural engineering and non-destructive evaluation and carry actionable implications for the design of programs and policies targeting in-service bridge structural health monitoring to supplement visual inspection and extend inspection intervals.