Green geopolymer mortars for masonry buildings: effect of additives on their workability and mechanical properties

The fight against climate changes has encouraged the development of most researches on new binders, with the aim of progressively reducing the use of Ordinary Portland Cement, with its huge carbon footprint. Within this context, geopolymer-like binders can represent an eco-friendly alternative, also for the production of mortars for masonry buildings. In this work, a “one-pot” all in powder formulation was developed to the purpose, and special attention was given to explore the influence of different additives on mortar workability and mechanical properties. Different types of adhesives (like rice starch or maize starch, and alginate) were considered, which were separately applied at first, and finally mixed together with water retention additives and superplasticizers. The obtained results highlighted the achievement of an adequate workability and adhesion to the support, at the cost of reduced mechanical performances.