Paper Title
Role Alkali Activated Binders in Cement Pastes Containing Recycled Concrete Fines

Abstract
Production of cementitious materials utilizing demolition waste is usually limited to the use of coarse aggregates. On the other hand, utilization of fine fractions containing stripped mortar remains an issue to be solved. In the presented study, we studied pastes containing 50% finely ground recycled concrete, blended with Portland cement, fly ash, or blast furnace slag. The microstructure of these pastes was studied using SEM-BSE microscopy and EDX analysis, stages of hydration were monitored using calorimetry, and mechanical strength was determined from destructive tests. The results show that recycled even fine fractions of concrete waste can be efficiently incorporated into cementitious materials and even improve their properties.