부산대학교 도서관

A multichannel linear array Rayleigh wave (R-wave) methodology is studied for evaluating subsurface cracks on concrete. Numerical simulations were first conducted to understand the propagation of R-waves in steel-reinforced concrete comprising subsurface cracks with different depths and lengths followed by a series of experimental measurements on concrete samples with induced artificial subsurface cracks. The changes in R-wave amplitude and velocity were analyzed to obtain correlations with the crack depth-to-wavelength/length-to-wavelength ratio. Results revealed that the difference between the estimated and actual characteristics of subsurface cracks (crack length and depth) was less than [+ or -]20%, showing a possibility for using R-wave methodology to assess subsurface cracks in reinforced concrete with the proposed acquisition, extraction, and analysis methodology. Keywords: amplitude; excitation frequency; Rayleigh wave; reinforced concrete; subsurface crack; velocity.
INTRODUCTION Increasing development in the construction industry, as well as aging buildings, results in a high demand for appropriate nondestructive testing (NDT) methods to inspect and evaluate the conditions of [...]