Size-independent strain gradient effective models based on homogenization methods: Applications to 3D composite materials, pantograph and thin walled lattices

2021 ◽  
pp. 115065
Author(s):  
Ahmed Lahbazi ◽  
Ibrahim Goda ◽  
Jean-François Ganghoffer
2021 ◽  
Vol 5 (2) ◽  
pp. 36
Author(s):  
Aleksander Muc

The main goal of building composite materials and structures is to provide appropriate a priori controlled physico-chemical properties. For this purpose, a strengthening is introduced that can bear loads higher than those borne by isotropic materials, improve creep resistance, etc. Composite materials can be designed in a different fashion to meet specific properties requirements.Nevertheless, it is necessary to be careful about the orientation, placement and sizes of different types of reinforcement. These issues should be solved by optimization, which, however, requires the construction of appropriate models. In the present paper we intend to discuss formulations of kinematic and constitutive relations and the possible application of homogenization methods. Then, 2D relations for multilayered composite plates and cylindrical shells are derived with the use of the Euler–Lagrange equations, through the application of the symbolic package Mathematica. The introduced form of the First-Ply-Failure criteria demonstrates the non-uniqueness in solutions and complications in searching for the global macroscopic optimal solutions. The information presented to readers is enriched by adding selected review papers, surveys and monographs in the area of composite structures.


1999 ◽  
Author(s):  
Sungsoo Na ◽  
Liviu Librescu

Abstract A study of the dynamical behavior of aircraft wings modeled as doubly-tapered thin-walled beams, made from advanced anisotropic composite materials, and incorporating a number of non-classical effects such as transverse shear, and warping inhibition is presented. The supplied numerical results illustrate the effects played by the taper ratio, anisotropy of constituent materials, transverse shear flexibility, and warping inhibition on free vibration and dynamic response to time-dependent external excitations. Although considered for aircraft wings, this analysis and results can be also applied to a large number of structures such as helicopter blades, robotic manipulator arms, space booms, tall cantilever chimneys, etc.


2010 ◽  
Vol 20 (3) ◽  
pp. 491-510 ◽  
Author(s):  
V.V. Mykhas’kiv ◽  
O.M. Khay ◽  
Ch. Zhang ◽  
A. Boström

2020 ◽  
Vol 54 (28) ◽  
pp. 4457-4471
Author(s):  
Mamadou Abdoul Mbacké ◽  
Shahram Khazaie ◽  
Sylvain Fréour ◽  
Frédéric Jacquemin

The composite materials used in marine environments are subjected to mechanical loads along with the water absorption. The analysis of the behavior of such materials requires to take into account the coupling between the mechanical and diffusion behaviors. The hygro-mechanical coupling has been widely investigated experimentally and numerically. This paper presents a numerical approach to model the hygro-mechanical coupling of composite materials. The diffusion process is modeled via the classical Fick’s law. The elasticity matrix is considered to belong to transverse isotropic class, i.e. the composite studied is a unidirectional one. The components of the former are considered as moisture content dependent. The constitutive law takes into account on the one hand the strain induced by the hygroscopic swelling and on the other hand the dependence of the mechanical properties (elastic constants along with the material ultimate strengths) on the moisture content. These are implemented in a finite element software used to investigate the influence of the hygro-mechanical coupling on the composite material behavior. The robustness of our numerical tool is investigated with some numerical case studies.


Sign in / Sign up

Export Citation Format

Share Document