@inproceedings{e30f5ca4299b422b918289f869b8eaf1,
title = "Characterization of entrained air voids using scattered ultrasound",
abstract = "The passage of ultrasound waves through highly heterogeneous media (e.g. hardened cement pastes that contain entrained air voids for protection against damage during freeze-thaw cycles) leads to significant loss of wave energy and an apparent attenuation of ultrasonic signal emerging from the heterogeneous zone. The size of this attenuation depends on the correlation properties of the medium (e.g. size and volume fraction of air voids) and the wavelength and frequency content of the incident waves. An estimated of the effect can be obtained using independent scattering theory under dilute concentration assumption. The resulting attenuation characteristics are illustrated numerically. These results are discussed in comparison with experimental data of longitudinal wave attenuation in the hardened cement paste containing a low volume fraction of entrained air voids of less than 10% for a large frequency range of 500 kHz-5MHz.",
keywords = "Cement-based materials, Entrained air voids, Ultrasonic scattering attenuation",
author = "W. Punurai and Jacobs, {L. J.} and Kurtis, {K. E.} and J. Jarzynski and J. Qu",
year = "2006",
month = mar,
day = "6",
doi = "10.1063/1.2184679",
language = "English",
isbn = "0735403120",
series = "AIP Conference Proceedings",
pages = "1335--1342",
booktitle = "Review of Progress in Quantitative Nondestructive Evaluation",
note = "Review of Progress in Quantitative Nondestructive ; Conference date: 31-07-2005 Through 05-08-2005",
}