Comparison of the durability of alkali-activated cements and ordinary portland cement using accelerated degradation methods

Abstract

This research focuses on the evaluation of the durability of alkali-activated mortars, using accelerated degradation methods, which allow us to analyze their impact on the resistance to chloride attack and corrosion of steel bars. The evaluation of the impact was carried out on mortars elaborated from the use of geopolymers, for which a dosage of zeolite, sand and calcium hydroxide Ca (OH)2 as solid part and an alkaline activator sodium hydroxide Na (OH) in combination with sodium silicate as liquid part were elaborated, additionally a control sample elaborated with Portland cement was prepared. Properties in the fresh state (workability in mortar), in the hardened state (compressive strength) and its impact on corrosion (accelerated corrosion test ASTM C876-91) were evaluated. It was demonstrated that the incorporation of geopolymers can represent an increase in compressive strength of more than 50% compared to samples made with OPC. The workability of mortars made with geopolymers is similar to mortars made with OPC. It is concluded that samples made with geopolymers showed a better resistance against a highly aggressive environment compared to mortars made with OPC, due to their less porous structure