Izbash Y. Development of the method of increasing the accuracy of the calculation fire resistance of steel reinforced concrete structures

The dissertation is devoted to the development of methods for increasing the accuracy of calculation of fire resistance of steel reinforced concrete structures. Object - processes for increasing the accuracy of calculation of fire resistance of steel reinforced concrete structures; goal - is to develop methods for improving the accuracy of calculation of fire resistance of steel reinforced concrete structures, due to specification of temperature fields, deformation diagrams, numerical modeling of stress-strain state, new methods of experimental research; methods - analytical and numerical methods for solving problems of building physics and building mechanics with the help of computer technologies, experimental researches; novelty - For the first time: obtained distribution of temperature fields in cross sections of steel-concrete constructions at standard temperature mode and temperature analysis of run-off structures of bridges under hydrocarbon temperature regime; developed methods of creating a mathematical model of deformation diagram of compressed concrete at elevated and high temperatures; developed methods of determination of the stress-strain state in steel reinforced concrete structures with the joint influence of loading and elevated temperature using computer technologies in linear and non-linear formations; numerical simulation of the stress-strain state in steel-reinforced concrete structures with the joint effect of loading and temperature in linear and non-linear formations was carried out to determine the features of the influence of temperature on their limiting state; new methods of experimental research, installation and samples of steel-concrete constructions have been developed; experimental researches of fragment model of steel reinforced concrete bridge construction were conducted. Improved: methods for determining modulus of elasticity of compressed and streched concrete, deformations, corresponding compressive and extension strength, boundary deformations and their corresponding boundary stresses; provided suggestions for regulatory documents; results – developed methods of calculation of steel reinforced concrete structures at different temperature regimes, as well as the interaction of temperature and load; new methods of experimental research, installation and samples of steel-concrete constructions have been developed; the offered methods allow to increase reliability of calculation of fire resistance of steel reinforced concrete structures, to develop their rational constructive decisions; implemented - at designing and working documentation Paul Wurth S.p.A. Itaia to build two blocks of coke oven battery; when developing the "Conclusion on the technical condition of bearing and enclosing structures of the trestle №1 of the complex of artificial constructions at the Lev Landau avenue in Kharkiv and the development of recommendations for repair, reinforcement and further exploitation"; when developing the project of reconstruction of road overpass on 1191 km of PC6 station Volnovaha of the regional branch "Donetsk railway" of PJSC "Ukrzaliznytsya"; industry - building constructions, buildings and structures.