Bashynska O. Creation of analytical models of constructions taking into consideration the concrete rheological properties

The dissertation is devoted to the development of a methodology for calculating reinforced concrete structures based on a double power law, taking into account the influence of physical nonlinearity and rheological properties of concrete, as well as taking into account the effect of changes in ambient temperature and when calculating the fire resistance. A universal technique has been developed for the numerous calculations of reinforced concrete structural elements that allows to take into account the effect of temperature variation in the cross section of elements on the reduction of mechanical and deformation properties. Also, an algorithm has been developed for determining the deformations of a structure, taking into account the occurrence of creep deformations based on a double power law. It improved an algorithm for determining the function of creep, taking into account the influence of changes in ambient temperature. It obtained the equations and the method of calculating the floor slabs when exposed to temperature factors, and taking into account the viscoelastoplasticity of concrete. A mathematical model was further developed, allowing to take into account the change in the ambient temperature and its influence on the development of nonlinear deformations, taking into account the reduction of the strength and deformation characteristics of the material. The proposed technique can be used in the design of buildings and structures in which creep deformations can occur. Completed numerous experiments allow us to determine the dangerous factors that characterize a possible change in the operating conditions of a building (increased plastic deformations or high-temperature effects, etc.). The above design calculation algorithms can be used when recalculating buildings and structures subjected to fire impact. The results of the study can be used to improve standards in the framework of ensuring the constructive safety of buildings and structures in case of exposure to high or elevated temperatures.