Alkali–aggregate reaction in activated fly ash systems

Certain aspects of the durability of a new cementitious material, alkali activated fly ash, are addressed in this article; specifically, a series of findings relating to the alkali-silica reaction are reported. The approach adopted in the study was to compare the new cementitious systems to analogous Portland cement mortars using aggregates of differing reactivity and a procedure based on the test described in ASTM standard C 1260. The results of SEM/EDX and XRD analysis of the materials showed that activated fly ash mortars performed better than the Portland cement equivalents.