Alkali-activated Portland blast furnace slag cement mortars: Performance to alkali-aggregate reaction

This report evaluates the performance to alkali-aggregate reaction of two types of binder systems: a Portland blended cement and an Alkali-activated Portland blended cement. The first system consists of 80% granulated blast furnace slag and 20% Portland cement (OPC) and was hydrated in the presence of water (CE), whereas the second incorporated an alkaline activator, making it a hybrid cement (HB). Expansion measurements of mortar bars were carried out, and their behaviour was compared to a reference system based on 100% OPC. Additionally, a microstructural characterization was performed using scanning electron microscopy. The results show that CE and HB cements had smaller expansions than OPC, although Rosette and pseudo-Rosette structures were observed.