Principles of compositional build-up of heat resistant materials made with alkaline cementitious materials

摘要

The study deals with the peculiarities of compositional build-up of the heat resistant concretes based on alkaline cements. It is shown that the regulation of heat resistance, and hence, the increase in durability of the heat resistant stone may be reached due to formation of a fragmentary microstructure of the stone when aluminosilicate additives, thermoactivated at various temperatures, are introduced into the cement composition to provide a target synthesis within the dehydration products of needle-shaped substances conductivity and the lower and coefficient of linear thermal expansion (C.L.T.E.) as compared with initial cement constituents. It is demonstrated that the highest thermal resistance after firing at T=1000 deg C (86-130 MPa) is characteristic of the chamotte-slag mixes with an additive of thermoactivated kaolinite at T=600-700 deg C in a quantity of 10-20 percent by mass. The heat resistance of concretes made with the developed cements exceeds by 10-15 water heat cycles that of the reference concretes made with the same cements without additives.