Effects of metakaolinite on concrete property

The concrete that is produced by replacing some amount of cement with natural and industrial mineral supplements is becoming widespread gradually. In recent years, there has been an increasing interest in the utilisation of metakaolin (MK) in cement-based materials as partial substitution or as cement additive. MK is processed from high-purity kaolin clay by thermal activation at a temperature range of 700?800 ºC and reactive alumina-silicate structure is formed.MK is a silica based product that, on reaction with Ca(OH)2, produces C-S-H gel at ambient temperature. MK also contains alumina that, on reaction with Ca(OH)2, produces additional alumina containing phases, including C4AH13, C2ASH8, C3AH6.As a result of this, there is an increases strength.In the context of the thesis, metakaolins (MK), produced temperatures between 450-800 ºC by calcined of kaolin clay, were used as the mineral admixture. 5 different mortar mixtures containingMK replacement 0%, 5%, 10%, 15% and 20% by weight of cementwere prepared. Compressive and flexural strengths (2, 7 and 28 days) of the samples were determined after the standard cure operation. Test results revealed that replacement level of MK and curing procedure adopted had significant effects on the durability characteristics. Mortar containing 20% MK replacements showed maximum compressive and flexural strength. Based on the results obtained from this study, mortars produced with MK, at an early age wasalso the contribution of compressive and flexural strength.