Durability aspects and mechanical strength of mortars containing glass powder and slag

Abstract

The combination of glass powder with pozzolanic additions to replace clinker can develop new types of binders (ternary cement) with improved physical and mechanical properties, and enabling the reduction of clinker and natural resources consumption, and the minimisation of the CO₂ emissions. In this context, the present work is an attempt to study the influence of glass powder (GP), with two different specific surface area (Blaine) GP30 = 300 m²/kg and GP45 = 450 m²/kg, combined with slag (S), on the mechanical behavior and durability of mortars. The mechanical properties were investigated using the compressive and flexural strength tests. In addition, aspects related to durability were examined as well by the water-accessible porosity, capillary absorption and sorptivity tests. The replacement rate of cement by glass powder varied from 10% to 20% and the proportion of slag was fixed at 10%. The results obtained showed that a binary mortar made with (20% GP45) replacement showed increases in 90-days compressive strength, while the ternary mortar with (20% GP45 +10% S) replacement gave the best result. The same trend is also valid for durability properties examined in this study. As well as, the combined use of GP and slag at 30% replacement levels seemed to give better instead of using GP alone.