A Numerical Study on the Electrochemical Treatment of Chloride-Contaminated Reinforced Concrete
Abstract
:1. Introduction
2. Modeling Framework of the ECE
2.1. The Governing Equations
2.2. Finite Difference Algorithm
3. Numerical Results
3.1. Model Parameters
3.2. Effect of the Treatment Duration
3.3. Effect of the Current Density
3.4. Effect of the Cover Thickness
4. Validation
5. Concluding Remarks
- (1)
- For experimental tests of the ECE, the treatment duration might not last more than 8 weeks with an appropriate current density of 1~3 A/m2. If only the efficiency is considered, there is no specific requirement about the cover thickness.
- (2)
- The overall trend of the numerical results agrees well with the experimental test for the chloride extraction, which suggests the feasibility of the current modeling scheme.
- (3)
- It is worthwhile to point out that several issues need to be further addressed for a more fundamental investigation. The convergence condition shall be presented. In addition, two factors shall be defined, i.e., the uncertainty of the ionic diffusion coefficient and the spatial variability within the concrete cover.
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Conflicts of Interest
References
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Ions | Cl− | Na+ | K+ | Ca2+ | OH− |
---|---|---|---|---|---|
Initial concentration (mmol/L) | 265.0 | 507.5 | 33.1 | 562.5 | 1400.6 |
Diffusion coefficient (10−12 m2/s) | 25 | 0.3 | 1 | 0.15 | 40 |
Charge number | −1 | 1 | 1 | 2 | −1 |
Molar mass (g/mol) | 35.5 | 23 | 39 | 40 | 17 |
Treatment Duration (Weeks) | Cl− (mmol/L) | Na+ (mmol/L) | K+ (mmol/L) | Ca2+ (mmol/L) |
---|---|---|---|---|
4 | 296.4 | 534.4 | 38.9 | 587.0 |
8 | 260.9 | 560.8 | 44.4 | 611.0 |
12 | 242.8 | 586.2 | 49.3 | 634.3 |
Current Density I0 (A/m2) | Cl− (mmol/L) | Na+ (mmol/L) | K+ (mmol/L) | Ca2+ (mmol/L) |
---|---|---|---|---|
1 | 296.4 | 534.4 | 38.9 | 587.0 |
3 | 128.8 | 549.7 | 42.3 | 603.9 |
5 | 48.4 | 564.8 | 45.5 | 620.6 |
Cover Thickness (mm) | Cl− (mmol/L) | Na+ (mmol/L) | K+ (mmol/L) | Ca2+ (mmol/L) |
---|---|---|---|---|
30 | 296.2 | 534.4 | 38.9 | 587.0 |
40 | 296.3 | 534.4 | 38.9 | 587.0 |
50 | 296.4 | 534.4 | 38.9 | 587.0 |
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Xi, Y.; Gao, Y.; Li, W.; Lei, D. A Numerical Study on the Electrochemical Treatment of Chloride-Contaminated Reinforced Concrete. Modelling 2022, 3, 374-384. https://doi.org/10.3390/modelling3030024
Xi Y, Gao Y, Li W, Lei D. A Numerical Study on the Electrochemical Treatment of Chloride-Contaminated Reinforced Concrete. Modelling. 2022; 3(3):374-384. https://doi.org/10.3390/modelling3030024
Chicago/Turabian StyleXi, Yanan, Yun Gao, Wenwei Li, and Dong Lei. 2022. "A Numerical Study on the Electrochemical Treatment of Chloride-Contaminated Reinforced Concrete" Modelling 3, no. 3: 374-384. https://doi.org/10.3390/modelling3030024