Using glass powder to improve the durability of architectural mortar prepared with glass aggregates

The waste glass was employed not only as decorative aggregates but also as a supplementary cementitious material in the architectural mortar. In terms of shrinkage, the incorporation of glass powder (GP) could significantly reduce the drying shrinkage of the glass mortars regardless of its fineness. When the glass mortars were subjected to high temperature (800 °C), the inclusion of GP into the mortars was more able to mitigate the flexural and compressive strengths losses as compared to the control glass mortar prepared without the use of GP. Furthermore, using the GP and glass aggregates simultaneously could effectively improve the resistance of the glass mortars to sulfuric acid attack and the positive effect was more pronounced when finer GP was incorporated. In particular, an encouraging result shows that the replacement of 20% cement by fine GP successfully suppressed the deteriorative alkali-silica-reaction (ASR) expansion caused by the glass aggregates. Also, the glass mortars incorporated with fine GP exhibited comparable or even superior durability properties than that of the fly ash blended glass mortar.