Effect of curing temperature on the early and later ages behaviour of Metakaolin blended cement mortars: hydration heat and compressive strength

Cement is one of the main sources of negative environmental impact of concrete. One way to reduce this impact of concrete could be through the reduction of the cement content. This could be achieved by replacing a part of cement with mineral additives such as fly ash, blastfurnace slag, silica fume, metakaolin (MK), etc. in concrete. In this paper, the effect of curing temperature on MK blended cements is investigated. Isothermal calorimetry and compressive strength tests are performed on mortars prepared with various replacement levels of cement by MK (5%, 15% and 25%) and cured at different temperatures (10°C, 20°C and 40°C). Further, water porosity test and microscopic observations were carried out to confirm the findings. Results showed that the pozzolanic activity of MK is conditioned by the curing temperature and its levels of replacement.