Continuum and discrete models for structures including (quasi-) inextensible elasticae with a view to the design and modeling of composite reinforcements
Continuum and discrete models for structures including (quasi-) inextensible elasticae with a view to the design and modeling of composite reinforcements
复制标题
DOI：
10.1016/j.ijsolstr.2014.12.014
复制
发表时间：
2015-05-01
影响因子：
3.6
通讯作者：
Boisse, P.
中科院分区：
文献类型：
--
作者：
d'Agostino, M. V.;Giorgio, I.;Boisse, P.
受航空工程中一些复合纤维增强材料的启发和构思新超材料的需要，考虑了包括(准)不可伸缩弹性体在内的离散模型。然后启发式地提出了一类近似描述引入结构的宏观力学行为的连续介质模型。其中一些连续介质模型可以看作是一种特殊的二次梯度弹性介质，其中较高梯度的弹性是由构成微观晶格的弹性体的弯曲刚度赋予的。通过设计适当的数值代码来研究离散模型，以避免数值不稳定和锁定，并尝试将离散模型与连续模型进行比较。研究结果表明，广义连续介质理论具有一定的工程应用价值，在机织复合材料力学中具有一定的应用价值。介绍的离散模型和连续模型被用来描述机织物的所谓偏向扩展测试，结果表明，正确再现目标现象的一个很好的选择是使用二次梯度连续理论。然而，正如全文所讨论的那样，在严格的微观-宏观识别程序的背景下，仍然有许多悬而未决的问题需要解决，特别是在处理受到特定限制的系统时，例如不可扩展。(C)2014爱思唯尔有限公司。保留所有权利。
Inspired by some composite fiber reinforcements used in aeronautical engineering and by the need of conceiving new metamaterials, some discrete models including (quasi-) inextensible elasticae are considered. A class of continuum models approximately describing the macroscopic mechanical behavior of introduced structures is then heuristically proposed. Some of these continuum models can be regarded as a special kind of second-gradient elastic media, in which the higher-gradient elasticity is conferred by the flexural stiffnesses of elasticae constituting the microscopic lattice. The discrete models are studied by means of suitably tailored numerical codes designed to avoid numerical instabilities and locking and a comparison of discrete versus continuum models is attempted. The obtained results show that the theory of generalized continua may be useful in some engineering applications and it plays a relevant role in the mechanics of woven composites. The introduced discrete and continuum models are used to describe the so-called bias extension test on woven fabrics and it is shown that a good choice to correctly reproduce the targeted phenomenology is to use a second gradient continuum theory. However, as discussed throughout the paper, in the context of rigorous micro-macro identification procedures there still remain many open problems to be solved, especially when dealing with systems subjected to particular constraints, such as inextensibility. (C) 2014 Elsevier Ltd. All rights reserved.