The article is devoted to some aspects of research of hostile environment influence on the concrete durability. The mechanism of formation of chaotically diversified difficult structure is described. Chemical interactions of cement with active components of diffusion in steam space are examined. Measures for receiving conditions under which the volume of products of reaction will be equal to the volume of the reacted alkaline components of a cement stone are offered. High-quality and quantitative changes in a pore space, which are irrespective of density and the relative molecular mass of reaction products are described. Besides, movement and distribution of gaseous products of reaction in volumes of a cement stone are simulated. Reasonable integrated dependences of influence of aggressive environment on various types of concrete surfaces are given. The methods of corrosion control offered in article allow substantially to lower or absolutely to exclude adverse effect of hostile environment on concrete and reinforced concrete structures already at a stage of selection of composition of concrete mix. In this case service life of concrete and reinforced concrete structures will increase.

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The article considers innovative materials for construction. Using mathematical planning methods, we studied how the quantitative composition, the biocidal additive and gypsum content influence on the compressive and flexural strength and density of the composites. We found that the more gypsum in a composition the higher compressive and flexural strength of a specimen. So, with the greatest degree of compositions filling (fly ash – 20 mass fractions, gypsum – 11.2 mass fractions) maximum compressive strength is 72.5 MPa. We determined when the fly ash content rises up to 20 mass fractions per 100 mass fractions of clinker, flexural strength rises too and specimen density decreases. The developed compositions of biocidal cements recommended for use in the manufacture of materials, products and structures for buildings and constructions, operating in aggressive environments.

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This paper presents a new approach to recognize a long-term strength of concrete. We introduce into the calculation a new concept of energy integrity of the specific energy of W-maximum resistance to the destruction. In the formation and aging process the concrete is considered to be a non-conservative system. Strength development implies the increasing of the demanded specific work for fracture. The results of the calculations show that for critical reinforced concrete constructions operate at a significant level of long-term loading. The coefficient of the working conditions should be given as differentiating, taking into account the predicted concrete creep.