Evaluation of reinforcement corrosion rate in concrete structures by electrochemical noise measurements

Experimental results on the polarization resistance estimation in a three-electrode setup that consists of two carbon steel electrodes and the silver reference electrode are presented. The corrosion rate varies with the conditions changing inside the concrete structure due to its irregular wetting in an aqueous solution of NaCl. The change of polarization resistance of a single steel electrode can be identified by voltage and current electrochemical noise measurements. The observed change does not exceed the factor of a few times of the originally recognized value. The newly proposed method of electrochemical noise analysis for monitoring of swift corrosion rate changes is presented in detail.