Protection galvanic anode ZLA

reinforced concretezinc

Zinc Layer Anode or simply ZLA is a high purity zinc foil (> 99.95%) coated with an ionically conductive adhesive. ZLA is a product used in the protection of reinforced concrete constructions against rebar-corrosion. ZLA is a sacrificial galvanic anode specifically designed for giving electrochemical protection, known as cathodic protection, for the prevention of corrosion of the concrete steel reinforcement. The current required for cathodic protection is provided by the galvanic link of the steel reinforcement and the zinc layer being part of the ZLA. No external power source or what so ever is necessary. The presence of chloride based salts within the concrete can be a threat to the passivation layer (protective oxyde-layer) on the carbon steel reinforcement of the concrete. Also variations in the concrete cover on top of the reinforcement, the quality of the concrete cover and the content of the chlorides around the reinforcement will cause similar corrosive circumstances. These circumstances will cause local corrosion cells. These places are called anodes. Other locations of the reinforcement, where the circumstances are relatively less corrosive and aggressive, remain passivated (passive oxyde-layer). These locations are called cathodes.