A nondestructive evaluation method for concrete voids: Frequency differential electrical impedance scanning

Sungwhan Kim, Jin Keun Seo, Taeyoung Ha

Research output: Contribution to journalArticle

10 Citations (Scopus)


This paper proposes a new nondestructive evaluation method for detecting cracks, voids, and other hidden defects inside concrete structures, called "frequency differential electrical impedance scanning (fdEIS)." The primary benefit of fdEIS over the conventional nondestructive methods is that it is possible to determine the thickness of the voids. In fdEIS, we inject a sequence of electrical currents with various frequencies through the tested concrete wall by applying a sinusoidal voltage difference between a surface electrode and a scan probe, which are placed on opposite surfaces of the wall. Through the probe, we measure the derivative d/dw gw of exit currents (Neumann data) with respect to the angular frequency variable w. We find the fundamental concept in fdEIS relating the thickness of the voids to d/dw gw and derive an approximation formula for estimating the thickness of the voids. We demonstrate the performance of our method in numerical simulations.

Original languageEnglish
Pages (from-to)1759-1771
Number of pages13
JournalSIAM Journal on Applied Mathematics
Issue number6
Publication statusPublished - 2009 Jun 30


All Science Journal Classification (ASJC) codes

  • Applied Mathematics

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