Identification of Tendon Ducts in Prestressed Concrete Beam by SIBIE

  • M. Yamada
  • K. Tagomori
  • M. Ohtsu
Conference paper
Part of the RILEM Bookseries book series (RILEM, volume 6)


The impact-echo method is well-known as a non-destructive testing for concrete structures. It is based on the use of low-frequency elastic waves that propagate in concrete to determine thickness or to detect internal flaws in concrete. In this method, the presence and the locations of defects in concrete are estimated from identifying peak frequencies in the frequency spectra, which are responsible for the resonance due to time-of-flight from the defects. In practical applications, however, spectra obtained include so many peak frequencies that it is fairly difficult to identify the defects correctly. In order to improve the impact-echo method, Stack Imaging of spectral amplitudes Based on Impact Echo (SIBIE) procedure is developed as an imaging technique applied to the impact-echo data, where defects in concrete are identified visually at the cross-section. In this study, the SIBIE procedure is applied to identify grouted or ungrouted post-tensioning ducts in prestressed concrete beam. It is demonstrated that the ungrouted duct can be identified with reasonable accuracy.


Impact-echo NDE Prestressed concrete SIBIE Ungrouted tendon duct 


  1. [1]
    Sansalone M.J. & Streett W.B. 1997a. Impact-echo, Ithaca, NY: Bullbrier Press.Google Scholar
  2. [2]
    Sansalone M. 1997b. Impact-echo: The complete story, ACI Structural Journal, 94(6), 777–786Google Scholar
  3. [3]
    Jaeger B.J. & Sansalone M.J. 1996. Detecting voids in grouted tendon ducts of post tensioned concrete structures using the impact-echo method, ACI Structural Journal, 93(4), 462–472.Google Scholar
  4. [4]
    Ohtsu M. & Watanabe T. 2002. Stack imaging of spectral amplitudes based on impact-echo for flaw detection, NDT&E International, 35, 189–196.CrossRefGoogle Scholar

Copyright information

© RILEM 2013

Authors and Affiliations

  1. 1.Graduate School of Science and TechnologyKumamoto UniversityKumamotoJAPAN

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