Corrosion inhibitors for reinforced concrete

This chapter briefly presents the mechanism of reinforcement steel corrosion in concrete, focusing on chloride-induced pitting corrosion, which is generally the main deterioration mechanism in reinforced concrete infrastructures. Corrosion inhibitors have long been proposed as one of many possible corrosion mitigation strategies. This chapter presents the state of the art on corrosion inhibitors used as admixtures, with particular emphasis on long-term and especially field studies. While there is a general agreement from both laboratory and field studies that mixed-in corrosion inhibitors can delay the onset of chloride-induced corrosion by a factor of 2–3, there are no results clearly demonstrating that corrosion inhibitors can reduce the corrosion rate after corrosion initiation. A particular lack of knowledge concerns organic corrosion inhibitors where conclusive long-term field results are lacking.