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Introduction: there is practically no information on the utilization of ash and slag waste (ASW) application in technology of special (noncontracting, expanding, self-stressing) cements, which predetermines the relevance of research in this direction. The study investigates the properties of experimental samples from cement, ash-and-slag and sand mixtures based on sulphoaluminate Portland cement (SAC) with an additive of the ASW. Materials and methods: a fine-particle binder material consisting of the SAC produced by the Podolsk Cement factory with a fine-grained ASW additive was used to obtain a binder mixture. Silica sand functioned as fine aggregate. All the raw materials used were local to the Russian Federation. The setting time, soundness, and strength of the binder mixture were determined according to GOST 30744-2001 standard. The specific surface area of the Portland cement was established through the use of the air permeability method utilizing of PMTs-500 instrument. The microstructure of the hardened binder mixture was studied employing electron microscopic analysis and X-ray phase analysis. Results: the work investigates the effect of 10 %, 15 %, 20 %, and 50 % ASW additive on the water demand, strength, and setting time of the SAC. The article also explores the kinetics of hardening and structure formation of samples from the binder mixture based on the SAC and ASW for hardening under normal conditions. Conclusions: results of the investigation allow recommending the ASW characterized by high dispersion as an additive for production of special cements without significant reduction of their properties. In the presence of the ASW, setting times of the cement mixtures virtually do not change as compared with the pure SAC. With limiting the amount of the ASW in the composition of the Portland cement, the strength characteristics do not practically change through the entire period of hardening.

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In this paper efficient types of binders – high alumina cements are considered. The shortage of industrial alumina and its high cost constrain the development of high-aluminate cements production. Waste from a number of metallurgical industries can be used as raw materials for their production. The aim of the investigation was to study the influence of metallurgical waste on the mineral formation of aluminate clinker and the properties of cement based on it. As a replacement of industrial alumina, dust of gas cleaning plants of aluminum electrolysis and slag of ferroalloys production were used. Aluminate clinkers were obtained in a laboratory furnace at a temperature of 1200-14000 °C. Mineral composition of clinkers was studied using chemical analysis, XRD and optical microscopy. The cements were obtained by grinding clinkers in a laboratory mill, then they tested for strength at the age of 28 days. It was established that the chemical and phase composition of dust allows to use it as a raw component in the production of high alumina cement. The investigations showed that the properties of alumina cement based on slag ferrovanadium production improved. Hydration activity of cement increases especially in the early period of its hydration.