COMPREHENSIVE APPROACH TO SOLVING PROBLEMS OF DURABILITY OF FERRO-CONCRETE BRIDGE DESIGNS

Abstract

Purpose. Prevention of premature failure of bridge structures. Methodology. Used: macrostructural, fractographic, analytical analyses, methods of physical and mechanical testing of concrete samples. Findings. In this work, the subject of research was not only the structural state and properties of concrete in bridge structures, but also the chemical properties of raw materials. Produced were the studies of prematurely destroyed slab-type bridge beams that showed: 1) inconsistency of raw materials with the requirements of the relevant standards; 2) the presence in the chemical composition of water of a large number of carbonate and hydrocarbonate complexes with sodium; 3) discrepancy with the requirements of modern technologies of methods and technological regulations of concrete production in conditions of the enterprise of PJSC "Ukrzaliznytsya". Innovative technologies for the production of reinforced concrete will prevent premature destruction of bridge structures. Originality. The work used a comprehensive analytical and technical approach to determining the causes that could affect the premature destruction of the bridge beams of plate type. The maximum number of factors that could adversely affect their premature failure was estimated. It is shown that the set of factors that adversely affected the structural characteristics of the concrete of the slab-type beams were significantly exacerbated by the presence of effective catalysts for destructive processes. The introduction to the requirements of modern Ukrainian standards of testing the structure of newly made concrete bridges will allow early detection of hazardous factors and predict the life of bridge structures. Practical value. Studies of the physical and mechanical properties of concrete samples manufactured using the new technology have confirmed their high level. The complexity of controlling the chemical composition of raw materials is greatly simplified by examining the microstructural parameters of the cement stone. The necessity of introduction of innovative technology of concrete and reinforced concrete production of bridge structures is proved.