Using Lamb Waves to Evaluate Debonding of Steel Plate Strengthened Concrete

Abstract

This is a preliminary study on using the dispersive characteristics of the Lamb wave modes traveling within the steel layer to assess the bonding condition. The dispersive curves are obtained by a multichannel analysis of surface waves. The frequency-phase velocity images obtained from finite-element analyses were constructed based on the phase velocity analysis scheme. These images were compared with the theoretical dispersion curves. The numerical models include pure steel, steel-concrete bi-layered and steel-epoxy-concrete composite plates. The results show the deviation of phase velocity for composite plate can be used to evaluate the bond condition.