Detection of Bridge-Deck Delamination Using Full Ultrasonic Waveform Tomography

Abstract

A two-dimensional (2D) time-domain waveform tomography technique is presented for detection of delamination in concrete bridge decks. Measured ultrasonic surface wave fields were inverted using a full waveform inversion (FWI) technique, based on a finite-difference solution of 2D elastic wave equations and Gauss–Newton inversion method. The FWI was applied to both synthetic and real experimental data sets. The real experimental data set was collected on a validation concrete slab using an ultrasonic shear-wave tomography system. The inversion results showed that the waveform analysis was able to delineate delamination zones, including a real delamination at a depth of 80 mm.