Concrete Delamination Characterization by Multi-Channel Sur- Face Rayleigh Wave Measurement

A non-destructive testing (NDT) technique is adopted to analyse concrete delamination by utilizing multi-channel acquisition of surface Raleigh waves (R-waves). This study embarks on examining the behaviour of R-waves propagating in concrete containing delamination. The aim is to identify the promising properties of R-wave such as wavelet transforms (WT) attenuation coefficient and phase velocity for reliable assessment. Numerical simulations of wave motions were conducted, followed by data processing to obtain correlations between the respective R-waves properties and characteristics of delamination. Results of analysis revealed that the (WT) attenuation coefficient were sensitive to the presence of delamination, inferring that simple waveform analysis can enhance the characterization of sub-surface delamination existed in concrete structures.