Corrosion can be defined as the degradation of a material due to a reaction with its environment.
Concrete corrosion is the chemical, colloidal or physicochemical deterioration and disintegration of solid concrete components and structures, due to attack by reactive liquids and gases.
The type of environment any concrete structure is exposed to, the depth of concrete cover over steel, and the rate of chloride ion absorption will dictate material means and methods selection to prevent corrosion for long term serviceability. In wastewater treatment for example, bacteria themselves do not have noticeable effect on concrete. However, sulfate-reducing bacteria in untreated sewage tend to produce hydrogen sulfide, which is then oxidized by aerobic bacteria present in biofilm on the concrete surface above the water level to sulfuric acid. The sulfuric acid dissolves the carbonates in the cured cement and causes strength loss, as well as producing sulfates which are harmful to concrete. Salts and other chemicals enter the concrete and cause corrosion. Corrosion of the metal leads to expansive forces that cause cracking of the concrete structure.
Cracks in the concrete allow moisture and salts to reach the steel reinforcement and cause corrosion. Constant wet / dry cycles, overall high ambient / surface temperatures, and aggressive humidity will more quickly cause steel to corrode in reinforced concrete. To increase concrete service life in these severe conditions, it will require very aggressive, multiple components noted above to arrest corrosion. No single component can stand alone to protect from concrete corrosion.To slow down the penetration of the aggressive agents, it is necessary to formulate and to make concrete, so that its porosity is low.
Some additional considerations for every repair application:
Epoxy Design Systems takes accountability for each and every construction project awarded using only manufacturer tested materials providing skilled trained technicians and technical knowledge. We provide efficient cathodic corrosion protection services to the United States and international clients. Give us a call today at 713-461-8733 or contact us online for a consultation.