Hilbert transformation of waveforms to determine shear wave velocity in concrete

Abstract

Given the density value, elastic properties of a homogeneous and isotropic material can be determined provided that primary and shear wave (P- and S-wave) velocities are known. P-waves are easier to monitor and detect compared to the S-waves. In concrete, along with P-wave velocity, shear wave velocity measurement is important in determining the elastic properties. These elastic properties could be implemented in assessing the quality of in-situ concrete. After an extensive literature survey, this study focused on the applicability of Hilbert transformation of waveforms to determine shear wave velocity in concrete material. The experimental work consisted of a set of ultrasonic measurements on the surface of a reinforced concrete deck. The recorded waveforms were then analyzed to obtain the arrival times of P- and S-waves. Hilbert transformation of the waveforms proved to yield reliable and repeatable results. (C) 2009 Elsevier Ltd. All rights reserved.