Geopolymers as a corrosion resistance material: a sustainable solution for smart cities

Massive usage of Ordinary Portland Cement in concrete structure has a crucial environmental impact, while using Alkali Activated Materials as an alternative is surrounded by several concerns shall be guaranteed, such as chloride binding capacity in the reinforced structures. Alkali activated materials (AAMs) have high proportions of calcium oxide, magnesium, aluminum, and silicon oxides which reflect their binding capacity. The behaviour of Alkali Activated material is not limited only to the chemical composition, but to the reactivity of its portions, the used activator and mix design also. In this paper two groups of alkali activated materials were tested first group Slag and Metakaolin binders tested in the normal curing condition with adding Sodium chloride salt (NaCL) percentages (0%,1%,2% and 4%) by mass, and the second group Slag binder tested in different curing conditions such as exposing the samples to oven 60° C, Microwaves 2 min with 450 W and steam curing at 60° C for 6 h to study the effect of the ambient curing condition used on the efficiency of the resulted geopolymer pastes. Through the implemented tests in the two groups our research stated that in contrast to Binding chlorides in OPC which are controlled by Aluminum and Silicon, in AAMs, the excessive existence of aluminum and silicon oxides is not the factor that governs the binding capacity of the chlorides. Also, calcium oxides had a satisfying effect on the binding and reactivity of other oxides. In addition to the rule of high temperature curing in calcium oxide reactivity exhibition.