Effective bending modulus of thin ply fibre composites with uniform fibre spacing

INTERNATIONAL JOURNAL OF SOLIDS AND STRUCTURES

卷:196

Article

Nourmohammadi, Nastaran¹  O'Dowd, Noel P.¹  Weaver, Paul M.¹ 

[1] Univ Limerick, Sch Engn, Bernal Inst, Limerick V94 T9PX, Ireland

关键词: Homogenisation;    Composite ply;    Effective bending modulus;    Length scale;   

DOI  :  10.1016/j.ijsolstr.2020.04.004

来源: Elsevier

【 摘 要 】

Cauchy homogenisation methods are based on the assumption that materials show size independent behaviour. For example, the effective bending modulus of a beam is constant for all cross-sectional areas and is equal to the tensile modulus. However, as demonstrated by numerous authors, the stiffness of heterogenous materials under non uniform loading (e.g. bending) can be influenced by size effects, when the microstructural size scale is comparable to the macroscopic one. In other words, an effective elastic modulus can underestimate or overestimate the bending stiffness depending on the specimen size. In this work, the effect of the thickness dimension on the effective bending modulus of composite plies is investigated. The composite is represented by cylindrical fibres uniformly distributed in a uniform matrix. The cases of fibres stiffer and more compliant than the matrix are considered. The results show that the effective bending modulus depends on fibre volume fraction ratio, mismatch of fibre/matrix material properties and the number of fibres through the thickness. The implications for the analysis of bending of thin ply composites are discussed. (C) 2020 The Authors. Published by Elsevier Ltd.

【 授权许可】

Free