Shape Effect of Electrochemical Chloride Extraction in Structural Reinforced Concrete Elements Using a New Cement-Based Anodic System
Abstract
:1. Introduction
2. Experimental Program and Materials
2.1. Case Studies Carried out
- Case study 1
- application of ECE to a cylindrical specimen with Ti-RuO2 mesh anode.
- Case study 2
- application of ECE to a cylindrical specimen with graphite-cement paste anode.
- Case study 3
- application of ECE to a rectangular section specimen with Ti-RuO2 mesh anode. ECE efficiency is obtained for a core sample extracted on the center of the biggest face of the specimen.
- Case study 4
- application of ECE to a rectangular section specimen with Ti-RuO2 mesh anode. ECE efficiency is obtained for a core sample extracted on the cover zone of the rebar, just over the steel.
- Case study 5
- application of ECE to a rectangular section specimen with graphite-cement paste anode. ECE efficiency is obtained for a core sample extracted on the center of the biggest face of the specimen.
- Case study 6
- application of ECE to a rectangular section specimen with graphite-cement paste anode. ECE efficiency is obtained for a core sample extracted on the cover zone of the rebar, just over the steel.
2.2. Materials Used
2.2.1. Concrete
Material | Dosage |
---|---|
Portland cement | 350 kg/m3 |
w/c Ratio | 0.6 |
Distilled water | 210 kg/m3 |
Limestone aggregate 4/6 | 466 kg/m3 |
Limestone aggregate 6/12 | 679 kg/m3 |
Limestone sand | 630 kg/m3 |
NaCl | 3.3% (2% Cl− relative to cement mass) |
2.2.2. Anodic Systems
Material | Dosage (for 5 kg of paste) |
---|---|
Portland cement | 1.389 kg |
Graphite powder | 1.389 kg |
Distilled water | 2.222 kg |
2.2.3. Electrolyte and Way of Moistening
2.2.4. Electric Power Source
2.3. Assembly of Specimens
2.3.1. Specimens with Ti-RuO2 Mesh Anode System
2.3.2. Specimens with Graphite-Cement Paste (GCP) Anode System
2.4. ECE Applications
2.4.1. Specimens with Ti-RuO2 Mesh Anode System
2.4.2. Specimens with Graphite-Cement Paste (GCP) Anode System
- -
- a reduction in current density, but never under 1 A/m2; and
- -
- the inclusion of pauses along the treatment.
2.5. Extraction of Core Samples
2.6. Chloride Analysis
3. Results and Discussion
3.1. Study 1. Circular Section with Ti-RuO2 Mesh Based Anode System
3.2. Study 2. Circular Section with GCP Based Anode System
3.3. Rectangular Section with Ti-RuO2 Mesh Based Anode System
3.3.1. Study 3. Core Sample in the Center of the Biggest Face
3.3.2. Study 4. Core Sample in the Concrete Cover Zone
3.4. Rectangular Section with GCP Based Anode System
3.4.1. Study 5. Core Sample in the Center of the Biggest Face
3.4.2. Study 6. Core Sample in the Concrete Cover Zone
Study | Horizontal section shape of specimen | Anode system | Core sample location | Average efficiency (%) |
---|---|---|---|---|
1 | Circular section | Ti-RuO2 mesh | 82.79 | |
2 | Circular section | GCP | 82.60 | |
3 | Rectangular section | Ti-RuO2 mesh | Center of the biggest face | 52.52 |
4 | Rectangular section | Ti-RuO2 mesh | Concrete cover over rebar | 85.22 |
5 | Rectangular section | GCP | Center of the biggest face | 64.38 |
6 | Rectangular section | GCP | Concrete cover over rebar | 76.15 |
4. Conclusions
Acknowledgments
Author Contributions
Conflicts of Interest
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Carmona, J.; Climent, M.-Á.; Antón, C.; De Vera, G.; Garcés, P. Shape Effect of Electrochemical Chloride Extraction in Structural Reinforced Concrete Elements Using a New Cement-Based Anodic System. Materials 2015, 8, 2901-2917. https://doi.org/10.3390/ma8062901
Carmona J, Climent M-Á, Antón C, De Vera G, Garcés P. Shape Effect of Electrochemical Chloride Extraction in Structural Reinforced Concrete Elements Using a New Cement-Based Anodic System. Materials. 2015; 8(6):2901-2917. https://doi.org/10.3390/ma8062901
Chicago/Turabian StyleCarmona, Jesús, Miguel-Ángel Climent, Carlos Antón, Guillem De Vera, and Pedro Garcés. 2015. "Shape Effect of Electrochemical Chloride Extraction in Structural Reinforced Concrete Elements Using a New Cement-Based Anodic System" Materials 8, no. 6: 2901-2917. https://doi.org/10.3390/ma8062901