Corrosion of Steel Rebars in Anoxic Environments. Part I: Electrochemical Measurements

Materials

Raul Arrabal¹  Javier Sanchez²  Nuria Rebolledo²  Elena Garcia²  Julio Torres² 

[1] Department of Chemical Engineering and Materials, Faculty of Chemistry, Complutense University of Madrid, Plaza de las Ciencias, Ciudad Universitaria, 28040 Madrid, Spain;Eduardo Torroja of Construction Science Institute (IETcc-CSIC), Serrano Galvache, 4, 28033 Madrid, Spain;

关键词: corrosion;    anoxic conditions;    reinforced concrete;    chloride;   

DOI  :  10.3390/ma14102491

来源: DOAJ

【 摘 要 】

The number of reinforced concrete structures subject to anoxic conditions such as offshore platforms and geological storage facilities is growing steadily. This study explored the behaviour of embedded steel reinforcement corrosion under anoxic conditions in the presence of different chloride concentrations. Corrosion rate values were obtained by three electrochemical techniques: Linear polarization resistance, electrochemical impedance spectroscopy, and chronopotenciometry. The corrosion rate ceiling observed was 0.98 µA/cm², irrespective of the chloride content in the concrete. By means of an Evans diagram, it was possible to estimate the value of the cathodic Tafel constant (b_c) to be 180 mV dec⁻¹, and the current limit yielded an i_lim value of 0.98 µA/cm². On the other hand, the corrosion potential would lie most likely in the −900 mV_Ag/AgCl to −1000 mV_Ag/AgCl range, whilst the bounds for the most probable corrosion rate were 0.61 µA/cm² to 0.22 µA/cm². The experiments conducted revealed clear evidence of corrosion-induced pitting that will be assessed in subsequent research.

【 授权许可】

Unknown