Nondestructive characterization of plates with an emphasis on civil infrastructure

Abstract

This work is aimed at developing a methodology for inspecting large plates, used in civil infrastructure, by Lamb waves. The traditional methods inspecting infrastructure are based on scattering of elastic waves from internal defects and on time of flight measurements. The methods based on elastic wave scattering can only detect defects larger than the wavelength of ultrasound used. The time of flight measurements have proven to be unreliable for strength analysis. This work investigates the potential of the Lamb wave technique to detect small defects when Lamb waves propagate over large distances. An innovative transducer holder setup is developed, which is the key to how Lamb waves can be generated and received in large structures.