CORROSION INHIBITING ADMIXTURE

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This admixture is specifically used to inhibit corrosion in reinforced concrete. Although reinforced concrete is generally a better construction material than the ordinary concrete , it's still brittle and liable to crack: in tension, reinforced concrete can fail in spite of its steel reinforcement, letting water in, which then causes the concrete to fail and the steel bars (re bar) to rust. Corrosion occurs in the presence of moisture, oxygen and an electrolyte. As chlorides attack the reinforcing steel, the salt intensifies the electrolyte properties of concrete, thereby creating a corrosion cell. As the corrosion reaction occurs, rust is formed. It migrates away from the reinforcing bar, leaving more iron to be corroded. This process continues and two situations develop:
1. The reinforcing bars disintegrate, which reduces the flexural strength of the concrete structure.
2. Iron, as it oxidizes, expands to four times its original volume. This expansion results in physical disruption of the concrete. Typical results are cracks, stains, crazing, spalling and pot holes; all of which are safety hazards.
The solution to corrosion in reinforced concrete is to add a corrosion inhibiting admixture to the concrete during batching. This will make the steel bars embedded in the concrete to be corrosion free and longer lasting.