Search academic texts

Information × Registration Number 0218U001284, 0117U004969 , R & D reports Title A development of methods for mathematical modeling of new and composite materials behavior for the lifetime estimation and reliability prediction of engineering elements popup.stage_title Head Larin Oleksiy, Registration Date 14-03-2018 Organization The Kharkov state polytechnical university popup.description2 RELIABILITY, ESTIMATION OF DESIGN LIFE-TIME, CORROSION DEFECT, RESTRENGTHENING BY COMPOSITE BANDAGE, ELASTOMERIC COMPOSITES, MICROMECHANICS OF HETEROGENEOUS MATERIALS, HOMOGENESIZATION, VISCOELASTICITY, SELF-HEATING The object of the work is the processes of deformation of mechanical engineering elements with new and composite materials, and processes of non-localized damage and localized volumetric defects development which is formed in elements during long-term operation due to fatigue, creep and corrosion. The aim of the work is to develop numerical methods for predicting of reliability and analysis of the structural strength of new and composite materials, as well as determination of the influence of degradation processes which are caused by fatigue, creep, corrosion and aging in such materials on the lifetime of mechanical engineering elements in operation based on the proposed approaches. Numerical models for the study of elastic and viscoelastic properties of materials based on their microstructures have been developed. Computational procedures for estimation of macromechanical characteristics are proposed. The visco-elastic characteristics of rubber-cord composites are determined on the basis of processing of experimental data of their cyclic deformation taking into account the process of self-heating. Analytical and semi-analytical approaches to the evaluation of the strength of layered composites with special features of geometry have been considered. As an independent part of the project, a prediction of the residual strength of curvilinear pipeline with statistically given corrosion defect has been carried out and the possibility of using composite bandages to restore the strength of that damaged structural elements has been studied. As the new results, the following can be underlined: New features of formation of anisotropy of viscous properties of two-directional composites has been established. The patterns of non-stationary heating for the sample of rubber-composite composites were determined during their cyclic loading along the fibers. The dependence of the area of the hysteresis loops of the material on the load conditions and the temperature of self-heating has been obtained. New regularities of the effect of volumetric corrosion defects on the concentration of stresses in structural elements with damages have been obtained, in contrast to the existing ones for curvilinear parts of structures and in a statistical formulation. The models and methods for estimating the residual strength of damaged structural elements and the possibility of restoring their strength have been further developed. The developed design approaches are allowed to further automation of the estimation of elastic and viscoelastic properties of composites with different internal design and develop the necessary software. The regularities of the influence of damage on the residual durability of structural elements are proposed to be developed to create systems for predicting the residual operating life-time. Product Description popup.authors Водка О.О. Вязовиченко Ю.А. Ларін О.О Львов І.Г. Мартиненко В.Г. Осетров А.О. Потопальська К.Є. Шаповалова М.В. popup.nrat_date 2020-04-02 Close