The quantities of POFA, FA, alkaline activator, and water used in the mixes were, respectively, 343, 343, 274, and 137 kg/m3. The binder content (POFA : FA) was kept constant at 50 : 50 with the variable of different proportions of fine aggregate contents. The measurements of N-sand, M-sand, and QD used in the mixtures are given in Table 4.