Dosage of Metakaolin in High Performance Concrete

This article deals with optimal dosage of metakaolin as addition in high performance concrete. The main criteria for assessing the optimal dosage of metakaolin was compressive strength, rheological behaviour and economic benefits. Metakaolin was added to the mixture of high performance concrete in the range from 0 to 25% weight of cement. The comparison of metakaolin and microsilica, which is often used by concrete producers due to its excellent properties, is also performed in this article. The experiments showed that using metakaolin as addition in high performance concrete affects the compressive strength and rheological behaviour positively. While the compressive strength increases especially at lower doses of metakaolin and at higher doses remained unchanged, changes in rheological behaviour were most obvious at the higher doses. From this point of view, it is possible to recommend a higher dose of metakaolin.