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Electrical impedance spectroscopy-based defect sensing technique in estimating cracks.

Zhang T, Zhou L, Ammari H, Seo JK - Sensors (Basel) (2015)

Bottom Line: A defect sensing method based on electrical impedance spectroscopy is proposed to image cracks and reinforcing bars in concrete structures.From various frequency-dependent electrical impedance tomography (EIT) images, we can show its advantage in terms of detecting both thin cracks with their thickness and bars.We perform numerical simulations and phantom experiments to support the feasibility of the proposed method.

View Article: PubMed Central - PubMed

Affiliation: Department of Computational Science and Engineering, Yonsei University, Seoul 120-749, Korea. zttouc@hotmail.com.

ABSTRACT
A defect sensing method based on electrical impedance spectroscopy is proposed to image cracks and reinforcing bars in concrete structures. The method utilizes the frequency-dependent behavior of thin insulating cracks: low-frequency electrical currents are blocked by insulating cracks, whereas high-frequency currents can pass through thin cracks to probe the conducting bars. From various frequency-dependent electrical impedance tomography (EIT) images, we can show its advantage in terms of detecting both thin cracks with their thickness and bars. We perform numerical simulations and phantom experiments to support the feasibility of the proposed method.

No MeSH data available.


Related in: MedlinePlus

Numerical validation of interface jump conditions of Equations (4) and (5): (a) relative error  for x ∈ 2 on dotted area of (b) at the frequencies 100 Hz, 1 kHz, 10 kHz, 100 kHz, 250 kHz and 500 kHz; (c) Relative error  for x ∈ 2 on dotted area of (b) at the frequencies 100 Hz, 1 kHz, 10 kHz, 100 kHz, 250 kHz and 500 kHz.
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f3-sensors-15-10909: Numerical validation of interface jump conditions of Equations (4) and (5): (a) relative error for x ∈ 2 on dotted area of (b) at the frequencies 100 Hz, 1 kHz, 10 kHz, 100 kHz, 250 kHz and 500 kHz; (c) Relative error for x ∈ 2 on dotted area of (b) at the frequencies 100 Hz, 1 kHz, 10 kHz, 100 kHz, 250 kHz and 500 kHz.

Mentions: Figure 3 provides the numerical validation of interface conditions in Equations (12) and (13) at the frequencies 100 Hz, 1 kHz, 10 kHz, 100 kHz, 250 kHz and 500 kHz. The potential uω is computed by FEM to obtain and for x in the dotted area of k. Figure 3a indicates the relative error at various frequencies of 100 Hz, 1 kHz, 10 kHz,100 kHz, 250 kHz and 500 kHz. Figure 3c shows the relative error with respect to over the dotted area of k. This numerical simulation shows that the relative errors are less than 10−1. Additively, when frequency is above 10 kHz, the relative errors are less than 10−3. Hence, ũω is reasonably close to uω in a region away from the cracks. (At low frequencies below about 1 kHz, /βk(ω)/ is very large, so that the jump condition in Equation (4) can be regarded as on 2. According to the transmission condition of uω and the assumption of σc/σb ≈ 0, we have , and therefore, uω ≈ ũω in a region away from the cracks.)


Electrical impedance spectroscopy-based defect sensing technique in estimating cracks.

Zhang T, Zhou L, Ammari H, Seo JK - Sensors (Basel) (2015)

Numerical validation of interface jump conditions of Equations (4) and (5): (a) relative error  for x ∈ 2 on dotted area of (b) at the frequencies 100 Hz, 1 kHz, 10 kHz, 100 kHz, 250 kHz and 500 kHz; (c) Relative error  for x ∈ 2 on dotted area of (b) at the frequencies 100 Hz, 1 kHz, 10 kHz, 100 kHz, 250 kHz and 500 kHz.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4481952&req=5

f3-sensors-15-10909: Numerical validation of interface jump conditions of Equations (4) and (5): (a) relative error for x ∈ 2 on dotted area of (b) at the frequencies 100 Hz, 1 kHz, 10 kHz, 100 kHz, 250 kHz and 500 kHz; (c) Relative error for x ∈ 2 on dotted area of (b) at the frequencies 100 Hz, 1 kHz, 10 kHz, 100 kHz, 250 kHz and 500 kHz.
Mentions: Figure 3 provides the numerical validation of interface conditions in Equations (12) and (13) at the frequencies 100 Hz, 1 kHz, 10 kHz, 100 kHz, 250 kHz and 500 kHz. The potential uω is computed by FEM to obtain and for x in the dotted area of k. Figure 3a indicates the relative error at various frequencies of 100 Hz, 1 kHz, 10 kHz,100 kHz, 250 kHz and 500 kHz. Figure 3c shows the relative error with respect to over the dotted area of k. This numerical simulation shows that the relative errors are less than 10−1. Additively, when frequency is above 10 kHz, the relative errors are less than 10−3. Hence, ũω is reasonably close to uω in a region away from the cracks. (At low frequencies below about 1 kHz, /βk(ω)/ is very large, so that the jump condition in Equation (4) can be regarded as on 2. According to the transmission condition of uω and the assumption of σc/σb ≈ 0, we have , and therefore, uω ≈ ũω in a region away from the cracks.)

Bottom Line: A defect sensing method based on electrical impedance spectroscopy is proposed to image cracks and reinforcing bars in concrete structures.From various frequency-dependent electrical impedance tomography (EIT) images, we can show its advantage in terms of detecting both thin cracks with their thickness and bars.We perform numerical simulations and phantom experiments to support the feasibility of the proposed method.

View Article: PubMed Central - PubMed

Affiliation: Department of Computational Science and Engineering, Yonsei University, Seoul 120-749, Korea. zttouc@hotmail.com.

ABSTRACT
A defect sensing method based on electrical impedance spectroscopy is proposed to image cracks and reinforcing bars in concrete structures. The method utilizes the frequency-dependent behavior of thin insulating cracks: low-frequency electrical currents are blocked by insulating cracks, whereas high-frequency currents can pass through thin cracks to probe the conducting bars. From various frequency-dependent electrical impedance tomography (EIT) images, we can show its advantage in terms of detecting both thin cracks with their thickness and bars. We perform numerical simulations and phantom experiments to support the feasibility of the proposed method.

No MeSH data available.


Related in: MedlinePlus