Study of the efficiency of epoxy coating protection of concrete surfaces from sulfuric acid corrosion

Abstract

The application of epoxy coatings to concrete is a method of its protection against sulfuric acid corrosion. The problem of ensuring the efficiency of the coating protection conditioned by many factors is considered herein. Penetration of acidic substances through local defects on the coating surface, which causes its swelling and a sharp increase in the corrosion rate, is one of the main factors. Results of the studies of the samples exposed to 5 % solution of sulfuric acid and to the environment of a sewer system with a high content of hydrogen sulfide in the air are described. It is established that the modification of concrete with additives and the increase of its physical and mechanical properties prevent the stability of the "concrete-epoxy coating" system from increasing. To ensure the reliable operation of reinforced concrete structures in an acidic environment, it is advisable to periodically monitor the condition of coatings in order to identify and to timely eliminate local corrosion.