Bond strength performance of ceramic, fly ash and GBFS ternary wastes combined alkali-activated mortars exposed to aggressive environments

Abstract

• Mortars with high WCP level showed excellent performance against acidic environment. • The bond performance of GBFS replaced mortars at elevated temperatures was enhanced. • Freeze-thawing resistance of mortars revealed inverse relation to the WCP and FA contents. The structural stability, safety and durability performance of the novel repair materials are decided by their interfacial bond strengths in the deteriorated concrete textures. In this view, the bond strength between the alkali activated mortars (AAMs) as the repair materials and normal concrete was studied following the standard ASTM C882 slant shear test. Three types of materials including the tile waste ceramic powder (WCP), fly ash (FA) and ground blast furnace slag (GBFS) were combined to produce these AAM binders. The prepared mortar binders were exposed to the acid attack, elevated temperatures, wet-dry and freeze-thaw cycles to evaluate their bond performance (as repair materials) against such aggressive environments. Various tests were performed to assess the bond strength loss after the exposure to different aggressive environments. The AAM mixes prepared with the high contents of WCP and FA revealed superior performance against the acid attack and elevated temperatures compared to the one contained high amount of GBFS. Meanwhile, the mortars designed with high the amount of GBFS displayed excellent bond strength performance when exposed to the wet-dry and freeze-thaw cycles. It is established that the proposed AAMs with outstanding bond strength performance and durability under aggressive environments are the suitable binders for various civil engineering construction applications.