Metakaolin-based Cementitious Materials

The metakaolin used in this study was sourced from a chemical company (Shanxi, China). The chemical composition and mineral composition of metakaolin (MK) are presented in Table 1 and Figure 1, respectively. It can be observed that the primary chemical components in MK were SiO₂ (55.54%) and Al₂O₃ (40.61%). From the perspective of mineral composition, MK was predominantly amorphous, while also containing minor amounts of kaolinite, illite, muscovite, and quartz impurities. The particle size distribution of MK is shown in Figure 2. NaOH (Analytical Reagent, shortened AR, 98%), Ca(OH)₂ (AR, 95%), CaCO₃ (AR, 98%), and CaSO₄ (AR, 97%) were purchased from Zhiyuan Chemical Reagent Co., Ltd. (Tianjin, China).