Open AccessANALYSIS OF ANALYTICAL MODELS AND THE DEPENDENCES REALIZED BY THEM FOR DEFINITION OF MECHANICAL CHARACTERISTICS OF COMPOSITE FILLERS
Author(s) -
Andrii Kondratiev
Publication year - 2021
Publication title -
komunalʹne gospodarstvo mìst
Language(s) - English
Resource type - Journals
eISSN - 2522-1817
pISSN - 2522-1809
DOI - 10.33042/2522-1809-2021-1-161-8-18
Subject(s) - moduli , materials science , composite number , elastic modulus , shear modulus , modulus , aggregate (composite) , basis (linear algebra) , shear (geology) , finite element method , composite material , structural engineering , mathematics , geometry , physics , engineering , quantum mechanics
The analysis of the accuracy of analytical models and the mechanical properties they implement is carried out for various types of composite aggregates of sandwich structures. The accuracy assessment of approximate analytical dependencies of the mechanical characteristics of the composite honeycomb core is given. The applicability of analytical dependencies at the initial stages of the design of cellular structures is established. The accuracy of the results of a numerical experiment is noted. This is due to the approximate nature of standard test methods. Both for the elastic modulus and for the shear moduli, their values obtained on the basis of information technologies of finite element analysis exceed their corresponding values determined by analytical dependencies. This excess over the corresponding analytical values for the shear moduli is close to a constant value for various reinforcement angles and does not exceed 1.14. For the elastic modulus of the first kind, the excess varies from 1.03 to 1.8 for various angles of cell reinforcement. The analytical dependences of the reduced mechanical characteristics of the tubular aggregate are obtained. The idea of the method for determining the mechanical characteristics of a tubular filler is to fulfill the requirement of equality of the relative axial and shear deformations of a conventional continuous type element and a real one, selected within one tube, taking into account only its material. The conclusion is drawn that the mechanical characteristics of the tubular aggregate, determined by the analytical model, to different degrees differ from the corresponding characteristics obtained on the basis of information technology of finite element analysis. Moreover, the difference in the elastic moduli of the first kind is much smaller than in the shear moduli. The reasons for these discrepancies are analyzed. It is justified and recommended to use constant correction factors for the analytical values of the reduced mechanical characteristics of the tubular aggregate, allowing their further use in the calculation of plate and shell sandwich structures.