Electrochemical and microstructural investigations on cathodicprotectedreinforced mortars under chloride ingress

摘要

Chloride ions constitute one of the deleterious agents that may cause or promote corrosion ofrnsteel reinforcement in concrete. Cathodic protection has been found to be one of the most viablerntechniques of inhibiting chloride induced corrosion of steel in concrete structures. This paper specificallyrnpursues exploring the electrochemical processes involved and the morphological aspects of corrosionrnproducts in reinforced mortars under cathodic protection. The quantitative characterization of mortarrnmicrostructure revealed that cathodic protection prevents efficiently the corrosion of steel, embedded inrnconcrete and induces favourable morphologies of the corrosion products, leading to the development ofrnmore protective layer at the steel surface. Furthermore, cathodic protection current influences ionrnmigration in the system, hence lowering the aggressive ions concentration at the steel/mortar (concrete)rninterface. The microstructural analysis provides supporting evidences to electrochemical measurements inrnterms of electrochemical behaviour and corrosion resistance.