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Modelling of deformation and failure of composite materials with stress state dependent propertiesтезисы доклада
- Авторы: Lomakin E.V., Fedulov B.N., Fedorenko A.N., Minaev N.G.
- Сборник: XLVII International Summer School – Conference Advanced Problems in Mechanics. June 24-29, 2019. St. Petersburg, Russia. Book of Abstracts
- Тезисы
- Год издания: 2019
- Место издания: Издательство Политехнического университета St. Petersburg, Russia
- Первая страница: 69
- Последняя страница: 69
- Аннотация: The analysis of the results of experimental studies of deformation properties of composite materials shows that of their properties depend on loading conditions. Thus, the mechanical properties of these materials are not invariant to the loading condition but depend on the stress state type that is caused by heterogeneous structure of composite materials, which particularly is displayed in the stiffness difference of composites under uniaxial tension and uniaxial compression, and under other biaxial and three axial loading conditions, too. This effect is most prominent for fabric-based composites and especially for woven carbon-carbon composites or carbon composites with three axial weaves. The values of elastic moduli of these composite materials under tension can be sometimes grater in comparison with elastic moduli under compression. The fibers are tightened up under tension but they can buckle under compression. Thus, the mechanisms of deformation are quite different for these loading conditions. The bending stiffness of fibers is much lower in comparison with the tensile one. Therefore, instead of a set of constant elastic coefficients, it is necessary to use a set of anisotropic functions of the stress state parameter and constitutive relations become nonlinear ones. Other types of nonlinearity of the behavior of composite materials are concerned the nonlinear response to shear loading, damage accumulation, strain rate effects. Theoretical models to describe different types of nonlinearity are proposed.
- Добавил в систему: Ломакин Евгений Викторович