Nonconventional alkaline activating solutions for alkali-activated mortars and concretes

Innovative solutions for reducing environmental problems associated with alkali-activated concrete are fundamental to make its use widespread. This study aims to present an overview of the production, characterization, application, and environmental aspects of alkali-activated mortars and concretes produced using nonconventional alkaline activating solutions. In this context, two different routes for the sustainable development of alkali-activated mortars and concretes were assessed: using an alternative silica source in the production of alkali silica solution and employing an alternative alkali source by replacing alkali metal hydroxide. The studies revealed a promising and sustainable future for the use of alkali-activated mortars and concretes with these alternative solutions. Several aspects are highlighted as future trends to continue with some studies and developments.