beton beschermen

Concrete is a very sturdy building material with great flexibility, which has been widely used in the Netherlands, especially in recent decades. Healthy concrete can last for years with relatively little maintenance. However, external influences can affect the concrete in such a way that the penetration of salts into concrete disrupts the synergy between concrete and reinforcing steel and can lead to concrete rot. Cathodic protection has been used commercially in concrete structures since 1980, and since 1986 also in the Netherlands. Cathodic protection can be used preventively at locations where there is a known aggressive environment, this is also called cathodic prevention.

Concrete rot is the problem of rusting reinforcing steel in concrete, the cathodic protection is in reality aimed at stopping the corrosion of the reinforcing steel. Concrete is durable, has a high compressive strength and a low tensile strength. Iron oxidizes if unprotected and has a high tensile strength. The combination of these two building materials offers a very nice synergistic effect: the iron absorbs the compressive strength that the concrete lacks and the high alkalinity of the concrete forms a protective layer around the reinforcing steel so that it does not rust.

If the acidity of the concrete is affected by external influences, the penetration of salts, and the steel is no longer protected, the reinforcing steel will rust, expand and push the concrete away. In addition, it no longer fulfills its purpose of absorbing the pulling force. Cathodic protection intervenes in the electrochemical corrosion process of the reinforcing steel, this can be done in two ways: Galvanic (GCP) or with impressed current (ICCP).

Op April 12, 2022