CONCRETE EVALUATION BY RADAR THEORETICAL ANALYSIS

The operating principles of a mobile high-resolution radar system that has been optimized for inspection of pavements such as highways, bridge decks, and runways are described. The waveforms generated by the high-resolution radar are illustrated as well as the interaction of these waveforms with the pavement structure. Graphic derivations of representative radar waveforms for varying conditions are shown by using time-domain analysis. This simplified method of analysis enables useful models to be made for a range of separation thicknesses and pavement base materials. The results of laboratory tests are presented in which radar illuminates a double slab of concrete and the spacing between the two slabs is varied discretely and precisely from 0 to 30 cm (o 10 12 in). For spaces up to 7.5 cm (3 in) between two similar materials, the amplitude of the radar echo appears to be nearly proportional to the same dimension. As the space increases to 15 cm (6 in), the signal increases primarily in width. For spaces greater than 15 cm, the radar signal splits into two separate waveforms, thereby resolving the upper and lower boundaries of the space. These laboratory data are related to in situ void data taken on airport runways. Finally, a detailed analysis of a single concrete slab, illuminated by the radar, is performed. The amplitude and phase properties of the reflected signal waveforms are derived independently based on time-delay measurement and a mathematical method. Both methods agree with each other and with the experimental data. (Author)

• Record URL:
  • http://onlinepubs.trb.org/Onlinepubs/trr/1982/853/853-007.pdf
• Summary URL:
  • https://scholar.google.com/scholar_lookup?title=CONCRETE+EVALUATION+BY+RADAR+THEORETICAL+ANALYSIS&author=A.+Alongi&author=T.+Cantor&author=C.+Kneeter&author=A.+Alongi&publication_year=1982
• Availability:
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• Supplemental Notes:
  • Publication of this paper sponsored by Committee on Performance of Concrete. Distribution, posting, or copying of this PDF is strictly prohibited without written permission of the Transportation Research Board of the National Academy of Sciences. Unless otherwise indicated, all materials in this PDF are copyrighted by the National Academy of Sciences. Copyright © National Academy of Sciences. All rights reserved.
• Authors:
  • Alongi, A V
  • Cantor, T R
  • Kneeter, C P
  • Alongi Jr, A
• Conference:
  • 61st Annual Meeting of the Transportation Research Board
  • Location: Washington District of Columbia, United States
  • Date: 1982-1-18 to 1982-1-22
• Publication Date: 1982

Media Info

• Media Type: Print
• Features: Figures; References;
• Pagination: pp 31-37
• Monograph Title: Concrete analysis and deterioration
• Serial:
  • Transportation Research Record
  • Issue Number: 853
  • Publisher: Transportation Research Board
  • ISSN: 0361-1981

Subject/Index Terms

• TRT Terms: Concrete tests; Laboratory tests; Pavements; Radar; Test procedures; Testing equipment; Void ratios; Waveform analysis
• Old TRIS Terms: Highway pavement; Radar applications; Waveform
• Subject Areas: Bridges and other structures; Highways; Materials; Pavements; I32: Concrete;

Filing Info

• Accession Number: 00368278
• Record Type: Publication
• ISBN: 0309033578
• Files: TRIS, TRB
• Created Date: Dec 30 1982 12:00AM