Corrosion behaviour of steel reinforced mortars based on alkali activated materials

Recently a great interest has been addressed towards the use of new binders with zero cement. In order to promote sustainability principles in the field of civil/building engineering, the set up and mix design of new building materials free of cements are very important goals. For this reason alkali activated materials have been largely investigated in these last years to evaluate if they can be used as new binder and cement replacement for specific applications. Between the properties that alkaline materials must fulfil, it is very important to investigate their interaction with steel and to understand if they can work as protective coating in aggressive atmosphere, such as marine environment. For this purpose, alkaline activated materials based on metakaolin and electric arc furnace slag, have been used to prepare steel reinforced mortar samples and their behavior as protective coating has been compared with the one shown by traditional cement based mortar. The results of electrochemical tests and microstructure analysis highlight that the investigated new binders are promising and can represent a valid green alternative to traditional cement