This study explores the potential of a calcined kaolinite-illite clay in LC3-type binders with the aim of assessing the material’s thermal resistance. After designing and characterizing the binder compositions, simultaneous thermal analysis (STA) was used to identify critical temperature ranges of phase transformations. Three key regions were detected: 50–300 °C (dehydration), 400–500 °C (Portlandite decomposition), and 650–750 °C (CaCO3 decarbonation). Between these, the material remained thermally stable. Based on this, 400, 600, and 1000 °C were selected as target temperatures for future heat exposure tests. The presented results form the basis for further investigation of the high-temperature behavior of this alternative cementitious system.



















