An Experimental Study on Factors Affecting Electro-Chemical Measurements of Steel Bars in Concrete
By Hamada Hidenori, Hirasaki Toshifumi, Yamaji Toru and Tarek U. Mohammed.
Concrete Research and Technology
Vol.15, No.1, Jan 2004 (Issue 34)
- Synopsis:
- Electro-chemical measurements are carried out to test the electro-chemical characteristics of steel bars embedded in concrete. Among several kinds of electro-chemical measurements, a) Mix potential (Half-cell potential) measurement, b) Polarization resistance measurement, c) Polarization curve measurement, are relatively widely used. Therefore, in a sense, they can be evaluated as an �gestablished technology�h. However, these measurements of steel bars in concrete essentially contain some inherent errors included in their measuring system. The factors affecting these errors are 1) potential difference between steel bar and reference electrode, 2) electrical resistance between steel bar and counter electrode. This paper describes a fundamental experiment carried out by using a double cellular system originated by authors, to evaluate these errors quantitatively. Based on the test results, the effects of above factors on electro-chemical measurements are evaluated.
- Keywords:
- electro-chemical measurement, half-cell potential, polarization resistance, polarization curve, potential step measurement, Grade of passivity
