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Information × Registration Number 0306U001150, 0105U001332 , R & D reports Title Development of the theory and methods for prognostics processes of deformation of thin-walled and solid constructions under static and dynamic loads with a different nature popup.stage_title Розробка теорії та методів прогнозування процесів нелінійного деформування тонкостінних і масивних конструкцій при статичному і динамічному навантаженні різної природи на основі розробки універсальних математичних та розрахункових моделей Head Bazhenov Viktor Andriyovich, Registration Date 07-02-2006 Organization Kiev National University of bildiny and tecture popup.description2 In the course of realization of work the theoretical fundamentalses of a research of processes deformation of thin-walled and massive constructions were developed under static and dynamic shipments with a different nature. The numerical technique of construction of borders of elastic systems’ dynamic stability areas under stochastic parametric excitation is considered. The problem of splitting of correlations in dynamic systems is solved by the help of two approaches. The influence of random excitation correlation radius on convergence of instability regions borders estimations is analyzed. The discrete three-dimensional model of thin multilayer shells with step-variable thickness is developed. By this model at the uniform methodological positions the different classes of inhomogeneous shells are built: with a multilayer structure of a material, constant and continuous-variable thickness, with edges, channels, recesses, holes, breaks of middle surface, – at an operation of force and temperature loads.The new universal space multilayer finite element, element, which is eccentrically situated relatively the shell's middle, is developed. The element is spreaded both to the parts of step-enlarges and to the parts of step-reduces thickness. The shells of an arbitrary configuration which are under an operation of the impulsive outward high-power loads are considered. The theoretical fundamentalses and universal algorithms for the numerical analysis of geometrically nonlinear dynamical deformation are developed. The created mathematical and calculated models are based on the using of the theory of plastic current, moment's scheme of a finite element method and methods of the numerical analysis. The physical equation of thermoviscoelastoplastisity and expression of stiffness matrix nodal reaction vector has been obtained for three-dimensional and semianalytic finite element method. The obtained expressions allows to carry out numerical analysis of stress-strain state evolution of spatial objects under static thermal-forced loading condition regarding of strain of different physical origin. Product Description popup.authors popup.nrat_date 2020-04-02 Close