Safety and durability of reinforced concrete structures is one of the most important requirements for projecting buildings. The standards and guidelines only contain common requirements about concrete quality and concrete cover. In very critical cases, for example the ingress of chlorides, the application of different coatings is presently the only possibility to protect the reinforced concrete structures, before corrosion is initiated. In case of depassivation of reinforcement the modelling of corrosion would be more practical. One subproject of a DFG-research project (FOR 537) is currently performed at BAM, the Federal Institute for Materials Research and Testing. In practice the reinforcement is depassivated locally by the ingress of chloride and parts of the steel become anodic and other cathodic areas. At the anode a significant mass loss can be determined after a period of time, caused by an electric current between the local anodic and cathodic areas. Thereby the relation between both areas can be in a range of decades, the effect is called element corrosion. In civil engineering practice higher mass losses can be observed, caused by an additional part of mass from the hydrolysis at the anode. This part is called self-corrosion and must be considered for the life time prognosis. Therefore the aim of the work presented is to identify the part of self-corrosion by the determination of electrochemical parameters and mass losses. The electrochemical parameters were detected by suitable electrochemical measurements, depending on different concrete parameters and different climates. In this paper the development and the scale of self-corrosion are presented. Furthermore the results of the electrochemical measurements, like potential and polarization resistance are shown. The results are compared and discussed, considering the different concrete parameters and storing conditions.
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