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Information × Registration Number 0215U004163, 0113U001471 , R & D reports Title Determining fire-resistive limits of reinforced concrete constructions taking into account the influence of concrete modifiers popup.stage_title Head Pozdeev A., Registration Date 12-02-2015 Organization Cherkasy institute of fire safety named after Chernobyl heroes National university of civil protection of Ukraine popup.description2 Report on SRW: The object of study - Fire concrete beams. Subject of research - the impact modifiers of concrete Fire concrete beams, which is determined by calculation. Purpose - The features of modifiers of concrete reinforced concrete beams on fire as justification for improving the calculation method of its determination. Research methods and instruments. For samples were used in the formation of heavy concrete as cubes and cylinders of the most common with common additives for improving the quality of the concrete mixture. During a comprehensive study of the thermophysical properties of the samples used experimental methods for studying the behavior of the samples during heating, methods of optical and scanning electron microscopy, the methodology for solving inverse heat conduction problems. For numerical data processing and modeling the behavior of structures under thermal effect of fire, taking into account their nonlinear behavior of the method of finite differences and finite element method. Theoretical and practical results. The effect modifiers in the composition of the concrete on the value of the fire resistance of reinforced concrete beams using complex obtained data on thermal and mechanical properties of modified concrete at high temperature under fire conditions. A method of calculating the fire resistance of reinforced concrete beams with the influence of modifiers of concrete. Scientific novelty of the results. For the first time found that the presence of modifiers increases speed heating concrete samples, and to the greatest increase in speed (up to 9% in relation to the concrete without additives) leads presence in the concrete plasticizers, and this can be reflected on the verge of fire, reducing it by up to 10% . For the first time developed a set of experimental procedures combined testing of concrete samples and interpretation of the results of these tests to determine mitsnisnih plastic and elastic properties of concrete superplasticizers and with antifreeze additives for high temperature heating. Effectiveness of implementation. Is to develop and study method of accounting for the effect of superplasticizers and antifreeze additives, which are almost always part of the industrial production of concrete, with the calculation of the fire resistance of reinforced concrete beams made based on it using the finite element method. As a result of the technical requirements set out in order to achieve maximum efficiency of this method, based on the set of the concrete impact of technological heredity associated with the presence of additives to improve the quality of concrete mix on thermal and mechanical properties of concrete specimens obtained adequate results with respect to the fire resistance of reinforced concrete beams. Scope. The developed techniques embedded in the educational process of the Academy of Fire Safety them. Heroes of Chernobyl in creating complex laboratory work (lab work for the discipline "Buildings and structures and their behavior in fire"), as well as proven in studies of fire resistance of structures in the experimental shop laboratory fire resistance of building structures NIISK Kiev, as well as used in the development of standards DSTU-H B EN 1994-1-2: 2010. "Eurocode 4. Design of composite steel and concrete structures. Part 1-2. Structural analysis of Fire (EN 1994-1-1: 2004, IDT) ", DSTU-H B EN 1995-1-2: 2010" Eurocode 5. Design of timber structures. Part 1-2. Structural analysis of Fire (EN 1995-1-2: 2004, IDT). " Keywords: reinforced concrete beams, concrete modifier, computational methods, fire rating. Product Description popup.authors Касярум Сергій Олегович Некора Ольга Валеріївна Нуянзін Віталій Михайлович Рудик Іван Віталійович Семенчук Олександр Миколайович Тищенко Олександр Михайлович popup.nrat_date 2020-04-02 Close