Calcined clay in highly substitued pozzolanic cements

The research is about the use of calcined kaolinitic clay in highly substituted pozzolanic cements. It also compares the reactivity of calcined kaolinitic clay with fly ash and the effect of the reactivity on binders with equal clinker substitution levels. The study also investigated the chemical and physical properties of a local kaolinitic clay deposit, evaluated its pozzolanic reactivity after calcination, and compared its performance as an SCM to that of commercially used fly ash, with the aim of establishing whether thermally activated South African kaolinitic clay can serve as an effective replacement for clinker at equivalent substitution levels. The clay was thermally treated at various temperatures, and the influence of calcination conditions on reactivity was determined. The Frattini test verified that portlandite consumption was indicative of enhanced pozzolanic performance.