Filler effect and pozzolanic effect of glass powder in mortar

Abstract The use of ground glass as a partial substitute for cement has been studied for its good performance, especially when its particles are smaller than 300 µm. Thus, this study focused on evaluating the behavior of mortar mechanical properties through the filler effect and the pozzolanic effect of glass powder. Cement substitution proportions with glass powder (0%, 10%, 20%, 30%, and 50%) having a granulometry below 75 µm were tested. To distinguish between the filler effect and the pozzolanic effect, limestone filler, having a similar particle size distribution to glass, was used. The tests evaluated axial compressive strength, capillary water absorption, tensile strength by diametral compression, and static modulus of elasticity. The results showed that 20% cement substitution with glass powder improved mechanical properties, evidencing both the filler and pozzolanic effects. The chemical activity of the glass powder was slower, but it resulted in a 24.06% increase in compressive strength at 91 days, highlighting the contribution of the pozzolanic effect.