Resistance of alkali-activated slag mortar to abrasion and fire

Abstract

This study investigates the durability of alkali-activated slag mortar exposed to abrasion and fire. Alkali-activated slag mortar is made by activating ground-granulated blast furnace slag with sodium hydroxide, sodium carbonate, sodium metasilicate and sodium silicate without adding Portland cement. Mortars were made with CEN reference sand, ground granulated blast-furnace slag, alkali-activator and natural spring water. The sand–slag and water–slag materials ratios were 3·0 and 0·50 for all mixtures, respectively. At 28 days, the specimens were exposed to horizontal Böhme abrasion and vertical grinding abrasion tests and to an elevated temperature of 1000°C for a fire test. The highest abrasion resistance was observed from the slag mortar activated by sodium silicate and sodium metasilicate. Sodium hydroxide showed superior fire resistance when compared with Portland cement mortar and other alkali-activated slag mortars.