Use of Alternative Alkali-Activated Mortars for Textile Reinforced Mortar Systems

The need for repair and strengthening existing buildings has become fundamental in the construction sector. At the same time, the efforts to reduce global CO2 emissions are leading to the development of building materials with low environmental impact, such as those based on alkali-activated mortars (AAMs). When compared to traditional mortars, AAMs allow to reduce CO2 emissions in a range from 30% to 80%. Recent studies have demonstrated the possibility of using AAMs as alternative matrices for structural strengthening systems, such as Textile Reinforced Mortar (TRM). This study evaluates the possibility of using different formulations of AAMs, based on metakaolin or fly ash, for TRM applications. The newly developed TRMs are compared in terms of physical and mechanical performances with two commercially available TRMs, based on lime or cementitious mortars. A bidirectional basalt fabric was used as internal reinforcement. The effectiveness of these new systems, also referred to as Textile Reinforced Alkali-Activated Mortars (TRAAMs), has been evaluated through direct tensile tests on prismatic coupons and shear bond tests on clay brick substrates. Experimental results showed that AAMs can be very promising as sustainable alternative to traditional mortars for TRM systems.