Influence of clay mineral composition on properties of blended portland cement with complex additives of clays and carbonates

Abstract

Resources of currently used mineral additives in production of blended Portland cement do not provide their increasing needs. The complex additives which differ in the presence of a synergetic effect in the co-introduction of multiple mineral additives play the great importance in creation of blended cements. One of the promising directions is creation of complex additives based on combination of calcined clays with limestone. But sometimes there are clay impurities in carbonate rocks which adversely effect on properties of received cements and concretes. At the same time calcium carbonate contained in marl clays during calcination allows to get high quality pozzolanic material. The effective complex additive based on the calcined mixture of clay and limestone was the creation. The results of research show the influence of the complex additive on blended cement stone properties. It has been established that strength of cement stone with complex mineral additive depends on the content of kaolinite in initial clay, and on calcination parameters.