Physico-chemical Properties of the Hardened Blended Cement Pastes Made of OPC- MK Blends CKD

In blended cement, it was known that, metakaolin (MK) has a pozzolanic activity. It is reported that MK is more active when it fired. On the other side, cement kiln dust (CKD) with high alkali and sulfate content can be considered an excellent activator for pozzolanic materials. This study deals with the investigation of the hydration characteristics of pozzolanic cement pastes by blending various proportions of CKD with OPC (75%)-MK(25%) blend. The hydration characteristics of hardened cement pastes were investigated with respect to compressive strength, combined water content, free lime content, bulk density, and total porosity under different curing ages up to 180 days. The microstructure of hydrates was investigated using SEM technique.