Cathodic Protection is commonly used in structures such as jetties, ship hulls, foundation of offshore wind mills, offshore oil drilling platforms and exterior of pipelines buried in soil or water. Especially, corrosion of steel piles and steel sheet piles buried in corrosive soil or immersed in water can be stopped by installing a properly designed and engineered Cathodic Protection System.
The corrosion rates of those areas typically vary between 0.1-0.3 mm/year. However, much higher corrosion rates are commonly recorded. The atmospheric zones of e.g. the sheet piles cannot be protected with a Cathodic Protection System because of the lack of electrolyte. Best protection can be achieved in the most vulnerable zone against corrosion, tidal zone. Combined with a coating solution the Savcor Cathodic Protection will provide a long lasting and economical protection for any steel structure in a corrosion aggressive environment.
Picture above: Savcor installed a Cathodic Protection System to bridge´s corroding underwater sheet pile foundations in 2018. The bridge was built in 2014 and in one year the corrosion problem was recognized.
Corrosion is one of the main reasons causing repair work of concrete structures. Contributing factors to corrosion of reinforced steel in concrete, typically, are design and construction failures, load and structural issues, environment (temperature and moisture) and concrete quality (low cover over the reinforcement, porosity, accelerators and other mixtures). These factors together with chloride ingress from de-icing salt or sea water will lead to an increased risk of corrosion. Once chlorides have destroyed the protective oxide layer from steel surface, corrosion will initiate leading to material loss. Corrosion products will eventually cause cracks in concrete and later dangerous spalling of concrete.
Due to the fact that corrosion of rebars happen inside of concrete and can´t necessarily be noticed from the surface, corrosion in concrete often causes surprises. The structure may collapse or extensive rebuilding is needed.
Savcor´s Cathodic Protection (CP) is a well-known and proven method to extend the service life of the reinforced concrete structures in case of chloride contaminated concrete corrosion. Cathodic Protection is usually applied during the ordinary concrete repairs. Cathodic Protection System in concrete consists of external DC power source, non-soluble anodes, cabling, reference electrodes and a control unit.
Savcor Cathodic Prevention technology for new reinforced concrete structures provides effective long-term corrosion resistance for structures expected to suffer from chloride-induced corrosion during their service life.
In new structures, the anodes can be installed directly to the steel reinforcement prior to concrete casting. When installing the CP during construction, savings in the CP installation shortens the payback time considerably, especially, in a corrosion intensive environment.
When a Cathodic Prevention is installed during the construction the access is there, already. Furthermore, when protecting a pristine structure, the protection current requirement is much less than the amount of current required to stop an on-going active corrosion.
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