Features of hardening and structure formation of concrete with high-dispersion mineral additives

Abstract

Abstract The article deals with the effect of micro-filler additives on the properties of high-strength concrete. The effectiveness of microcements – mixtures based on highly dispersed cement and silica fume – has been substantiated. Using the methods of thermokinetic analysis and thermoporometry, the processes of heat release and the formation of microporosity during the hardening of ordinary cement and microcements without additives and with the addition of silica fume are studied. The positive effect of silica fume on the hydration and formation of the structure of cement stone is proved. It is shown that the nature of the hydration interaction in the system of “microcement - silica fume” contributes to the compaction of the structure and reduce the development of shrinkage phenomena. It was revealed that the use of microcementives allows to increase the workability of concrete mixtures and to accelerate the rate of curing of high-strength concrete. According to the results of the studies, the high efficiency of the use of components of the type “microcement – silica fume” in the technology of high-strength and durable concrete has been proved.