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This paper deals with the characterisation by means of electrochemical, gravimetric and analytical methods of chloride-induced-corrosion behaviour of steel coupons embedded in chloride-containing-cement pastes. Corrosion rates were estimated from electrochemical measurements as well as gravimetric ones. They vary from 2.6 to 5.7 µm/year for 5 and 10 g/L chloride-containing-cement pastes. Analytical characterisations (including optical and electronical microscopy and Raman micro-spectroscopy) showed that corrosion patterns are not depending on the chloride content of the cement paste (5 and 10 g/L chloride in the interstitial solution). A localised corrosion pattern composed of pits growing inside the metallic substratum, a corrosion products layer (CPL) and a transformed medium (TM) was pointed out. CPL can be divided into two sub-layers (CPL1 and CPL2), characterised by the presence or absence of calcium coming from the cement matrix. [ABSTRACT FROM AUTHOR]

For reinforced concrete structures a localisation of all significant critical areas can only be done by a full surface inspection. The economic advantages are obvious: uncritical areas have not to be repaired expensively 1. The first step of the assessment should always be a visual inspection 2. The range of deterioration causes can be limited and the degree of deterioration may be estimated roughly. The inspection program can be adjusted to the requirements. By means of a full surface potential mapping areas with a high risk for chloride induced reinforcement corrosion can be localised, although no deteriorations are visually detectable at the concrete surface. In combination with concrete cover depth and resistivity measurements areas with corrosion promoting exposure conditions can be localised even if the reinforcement is not yet depassivated. The following publication gives an overview about the essential full surface investigation methods to localise critical areas regarding corrosion of steel in concrete. The selection of methods is based on the inspection procedure given in 2. [ABSTRACT FROM AUTHOR]