Corrosion in Concrete

Galvanized steel rebar in concrete reduces the corrosion rate to acceptable levels (i.e., 0.5 pm/year in most of the cases) as shown by the data in Table 4.81. 

The corrosion rates of rebar in concrete are high when the chloride content of the environment is high. Extensive laboratory test data on the corrosion of rebar in concrete are available.92 Field test data are limited by comparison. 

Corrosion in other environments such as organic media and gaseous atmospheres are discussed in the literature. Corrosion in organic media is dependant upon the viscosity and the presence of other chemical reagents. Corrosion in gaseous atmospheres is similar to atmospheric corrosion in requiring moisture and the formation of an electrolyte, which in turn can cause corrosion. The corrosion rate will vary with the type of gas such as N02 or S02 present. 

The corrosion of zinc electrode in zinc cells and batteries contributes to self-discharge, 

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Proc. Corrosion in Concrete B Practical Aspects of Control by Cathodic Protection, Seminar London, published by Global Corrosion Consultants, Telford, England, 1987. 

McKenzie, S. G., Techniques for Monitoring Corrosion of Steel In Concrete , Seminar Corrosion In Concrete-Monitoring, Surveying and Control by Cathodic. Protection , Global Corrosion Consultants, Telford (1986)... 

Arup and Partners, Electropotential Mapping of Corrosion in Concrete, HMSO (OTH 88286)... 

Meyer, W.J. and G.H. Hall (1979), Prediction of sulfide generation and corrosion in concrete gravity sewers A case study, J. B. Gilbert Associates, A Division of Brown and Caldwell, Sacramento, CA. 

Smith, P. (1987). Corrosion, Concrete, and Chlorides, Steel Corrosion in Concrete Causes and Restraints, SP-102, American Concrete Institute, 25-34. 

Hydrogen Sulfide. H2S is malodorous, toxic and corrosive especially at high humidities. It abounds in anoxic marine environments and is the major cause of corrosion in concrete sewer lines. Its oxidation products are mainly sulfur and sulfate. 

Z. P. Barant, Physical model for steel corrosion in concrete sea stmctures . Journal of the Structural... 

D. A. Hausmann, Steel corrosion in concrete, how does it occur . Materials Protection, 1967, 11,19-23. 

MP. Pedeferri, E. Redaelli, Prevention of steel corrosion in concrete exposed to seawater with submerged sacrificial anodes , Corro n Science, 2002, 44,... 

R. Myrdal, Embeddable Reference Electrodes for Concrete - A State of the art Report, European Federation of Corrosion, WP 11 Corrosion in Concrete, Task Group 5, Draft 3, August, 2000. 

There are many studies covering the mechanism of corrosion in concrete and assessment techniques (1-6). Specifications and recommended practices on how to select and apply repair methods (NACE SP1290 and 0390, BSEN 12696, BSEN 1504 and ACI222R-01) are given in the literature. 

Salt-induced reinforcing steel corrosion in concrete bridges is a serious problem and an economic burden. Although the positive effect of corrosion protection measures can be seen on individual cases, there are many bridges (thousands) without corrosion control. 

F. Mansfeld, M.W. Kendig, S. Tsai, Application of acoustic emission to detection of reinforcing steel corrosion in concrete. Corrosion 38 (1982) 9-14. 

Rebar corrosion in concrete is considered to occur in two phases [8]. The first phase begins with construction of the structure and ends with corrosion initiation when depassivating species reach the reinforcement. The second phase is the active corrosion that destroys the structure. Controlling rebar corrosion in this phase is very difficult. Passive film corrosion is initiated when local pore solution at the concrete-rebar interface drops below the passivation pH due to the presence of atmospheric carbon dioxide (carbonation) or chloride penetration. The following mechanism controls the carbonation process ... 

Hausmann, D.A. (1967). Steel Corrosion in Concrete How Does it Occur Materials... 

Broomfield, J., Davies, K., Hladky, K. and Noyce, P. (2003). Monitoring of Reinforcement Corrosion in Concrete Structures in the Field. Concrete Solutions, 1st Intern. Conference on Concrete Repari St.-Malo, France, Proceedings. M. Grantham, F. Rendell, R. Jauberthie and C. Lanos (eds). Publ Concrete Solutions (on CD Rom). 

Bolzoni, E, Lazzari, L., Ormellese, M. and Goidanich, S. (2006). Prevention of Corrosion in Concrete the Use of Admixed Inhibitors Proc. Corrosion 2006, San Diego CA, NACE International Houston. 

Annual Conference reports and standards on corrosion in concrete and concrete repair Corrosion and Materials Performance Journals, Training and certification courses in corrosion... 

Steel Corrosion in Concrete A. Bentur, S. Diamond and N. Berke Hb 0-419-22530-7... 

Fig. 6.83 Effect of chloride ions on the reinforcement corrosion in concrete. (According to [343])...

Chlorides concentration of 0.6% by mass of concrete is reducing the resistivity two times [60], Therefore, the progress of reinforcement corrosion in concrete can be assessed from measurements of surface resistivity [60],... 

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