Расчетно-экспериментальные исследования механических характеристик композитных матереалов

Research and use of composite materials for scientific experiments, engineering activities, as well as industrial purposes has expanded significantly, since the development of technologies for the production of composite materials has made it possible to create and research new types of their physical and chemical properties, reinforcement schemes and fiber lengths, etc. This paper presents the results of computational and experimental studies of the elastic and damping properties of a composite material. The studies were carried out on samples of laminated fiberglass, the dimensions of which are 160 × 16 × 4 mm, cut in three directions, in the direction of the warp, weft and at an angle of 45 degrees, five samples were cut in each direction. To study the mechanical properties of the obtained cantilever samples, the electrodynamic shaker was used. The study of damping properties was carried out by the Oberst method based on the experiment of the frequency response characteristics of cantilever samples. The determination of Young's moduli of laminated fiberglass samples was carried out by the dynamic method, and also the theory of vibrations of continuous systems was used. The experimental data obtained are compared with the results of numerical solutions performed by the finite element method (FEM). Geometric and finite element models were constructed and the natural frequencies and vibration modes of the samples were determined. Frequency and phase response characteristics are given. To reduce the error according to the results of the experiment, statistical processing was carried out. The values of the mathematical expectation and the standard deviation of the mechanical loss coefficient are calculated. The estimation of the measurement error was made on the assumption of the normal distribution of the error.