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International Journal for Multiscale Computational Engineering
Fator do impacto: 1.016 FI de cinco anos: 1.194 SJR: 0.554 SNIP: 0.68 CiteScore™: 1.18

ISSN Imprimir: 1543-1649
ISSN On-line: 1940-4352

International Journal for Multiscale Computational Engineering

DOI: 10.1615/IntJMultCompEng.v8.i4.70
pages 441-446

Developing a Novel Finite Elastic Approach in Strain Gradient Theory for Microstructures

H. Farahmand
Department of Mechanical Engineering, Islamic Azad University of Kerman Branch, Kerman, Iran
S. Arabnejad
Young Researchers Club, Kerman branch, Islamic Azad University, Kerman, Iran


Size-dependent effects can significantly be indicated in experimental deformation of microstructures. In accordance with statistic behavior of size-dependent parameters, it is predictable that finite deformation and nonlinear forms of equations may obtain more appropriate computational results for microstructures. In this paper, classic couple stress theory is used to explain size dependency in strain gradient theory. Based on results obtained from couple stress in strain gradient theory, the theory is extended in nonlinear form. In this case, a length scale parameter is used in this model as a Lagrangian coefficient and a strain gradient is attested in a classic constitutive equation as a constraint. Finally, a nonlinear form of equation is used for a cylinder in micron order subjected to torsion, and results are compared with a linear model, the model expressed by Yang et al. (Int. J. Solids Struct., 39, pp. 2731-2743, 2002), and the finite element model of bone.


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