Тип публикации: доклад, тезисы доклада, статья из сборника материалов конференций
Конференция: International Conference for Promoting the Application of Mathematics in Technical and Natural Sciences, AMiTaNS 2019; Albena; Albena
Год издания: 2019
Аннотация: Generalized rheological method is used to construct constitutive equations of fiber composite materials with the fibers having high tensile stiffness and low stiffness upon compression. Polymer-based composite reinforced by thin carbon fibers, used in the aerospace industry, was chosen as the material for research. The method for dПоказать полностьюetermining the effective moduli of elasticity, based on the analysis of the bending state of a thin rod, was implemented to check the material's moduli. Photos of the bent rod with cantilever bending were processed to obtain a plane projection, and then digitized using computer programs. The deflection data along the rod length was used further in solving the inverse problem of determining flexural stiffness (it was considered constant) using the least squares method. By means of Matlab functions, the problem of minimizing the standard deviation of the calculated deflection from the digitized one was solved on a discrete system of points along the axis of the rod. The deflection was computed by the finite difference method based on the generalized equation of the Euler elastic line which takes into account the flexural stiffness, deformation along the rod, Timoshenko effect (the effect of shear deformation) and Cosserat effect (the effect of independent turns of the reinforcing fibers relative to the matrix). Young's modulus upon tension was measured experimentally using standard technique. Young's modulus upon compression was calculated using the value of flexural stiffness corresponding to the best approximation of calculated deflection to the digitized deflection. As a result, it was shown that the ratio of moduli for the material under consideration is in the range of 50-60% and, if the calculation of flexural stiffness is made with Young's modulus under tension, then it is possible to obtain a relative error in the deflection up to 30% with the increased thickness of the rod.
Журнал: AIP Conference Proceedings
Выпуск журнала: 2164
Номера страниц: 090004
Издатель: American Institute of Physics Inc.