Protective Ability of Organic Coatings for Concrete under Chloride Attack

摘要

The corrosion of the steel reinforcement is the most dangerous degradation mechanism of concrete structures.Chloride ions attack is one of the causes of corrosion of steel in concrete.For this reason,in the last years,many protective coating systems have been suggested,in order to avoid the chloride ingress in reinforced concrete structures.In this work,three different organic coatings and two waterproofing Silanes compounds were applied on reinforced concrete specimens.A shotcrete and a polymer repair mortar were used for comparison.The specimens were then exposed to a chloride containing aggressive solution.The protective ability of the systems and the behavior of the embedded steel rebars were studied by means of Electrochemical Techniques,such as Potential Monitoring and Impedance Spec-troscopy.All the analyzed protective systems were found to be effective in improving the protection of the steel in comparison with concrete.Organic coatings showed the best results in terms of protective ability against chloride penetration.