To protect the reinforcement in the concrete from external influences, the protective layer of concrete between the outer surface of the concrete structure and the reinforcement must be thick enough and the reinforcement must not be too close to the outer surface of the hardened concrete structure. Therefore, before pouring concrete, it is important to check the position of the reinforcement in relation to the formwork to ensure that a protective layer of the correct thickness is formed when pouring concrete. Insufficient thickness of the protective layer can cause the concrete structure to carbonize as it ages, and the rust layer on the reinforcement can break the concrete layer covering the reinforcement by expansion, and the reinforcement can remain exposed to weather conditions, causing the concrete structure to decompose rapidly and lose strength.
Why is it necessary to measure the protective layer?
As the concrete structure ages, it is endangered by carbonation of the concrete. The reaction of the concrete with CO2 lowers the pH level (below 8), as a result of which the oxide-protective layer surrounding the reinforcement begins to decompose, the rust layer on the reinforcement pushes open the concrete layer covering the reinforcement and the reinforcement remains open to weather conditions.des lahti sarrust katva betoonkihi ning armatuur jääb avatuks ilmastikuoludele.
By properly measuring the protective layer, you can prevent moisture and chloride from entering the reinforcement, which reduces the risk of corrosion and decomposition of the concrete.
