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Presently, one of the actual problems of concrete science is the improvement of concrete formulations by using industrial waste, ultra-fine by-products from the production of aluminum and silicon industry, as well as modification by means of additives. The aim of scientific research is development of new technologies for obtaining concrete with enhanced performance characteristics. The article provides an overview of the causes of concrete destruction and methods for increased physical-mechanical characteristics and of concrete. The results of a literature search on the experience of using silica fume and polymers in concrete are presented. The advantages and disadvantages of using silica fume and polymers in the composition of concrete are identified. A study was carried out to determine the effect of various modifying additives on the physical-mechanical characteristics of concrete. Experimental studies have been conducted on the joint use of silica fume and polymers in concrete mixture. The results of the study are: the optimal amount of silica fume is 10-20 %, the optimal amount of polymer is 1.0-3.5 %. On the basis of tests to determine the strength revealed that the class of concrete increased from B15 to B30 compared with the composition of the control sample.

At present, one of the most promising areas in construction is the modification of concrete by means of a complex of modifying additives and production wastes that will allow to obtain concrete with improved technical and operational characteristics and solve a number of problems: import substitution and nanotechnology. The aim of scientific research is the development of new technologies for obtaining concrete with enhanced performance characteristics, provided that raw materials, energy and labor costs are minimized. The article presents the results of research work on the development of fine-grained polymer concrete, modified with microsilica. In the framework of the study, a literature review for the last 68 years has been conducted, devoted to the experience of using microsilica and polymers in concrete construction as a modifier for building materials. The main characteristics of the starting materials and modifying additives are determined. A study was conducted to determine the effect of various modifying additives on the physicomechanical characteristics of fine-grained concrete. The main rheological properties and strength characteristics of the entire spectrum of the investigated compositions are determined. A microscopic study of the structure was carried out. The result of scientific research is the establishment of an optimal combination of additives, the development of cement concrete with the use of microsilica and acrylic dispersion and the determination of the effect of additives on the physical and mechanical properties.

Concrete is one of the most common construction materials. Strength and frost resistance are the main and most important properties of concrete. Frost resistance of concrete is very important for buildings and constructions erected in Russia, since many regions are characterized by harsh climate conditions. These climatic conditions include: low temperatures, fluctuations of both temperatures and humidity. As a result, concrete saturates with water, and after repeated alternating freezing and thawing, concrete may start damage. The idea of my scientific investigation is to develop a new technology of manufacture of the concrete possessing improved technical and operational characteristics, first of all, frost resistance. Within the frames of the present investigation, we studied the available experience of applying silica fume and polymers in concretes in the capacity of modifying additives used to elevate frost resistance. An optimal ratio of the additives was found, and the optimum composition of polymer concrete modified with silica fume was developed. Investigations bound up with determination of the principal physical and mechanical properties have been conducted.