Microelastic wave field signatures and their implications for microstructure identification

INTERNATIONAL JOURNAL OF SOLIDS AND STRUCTURES

卷:49

Article

Gonella, Stefano¹  Liu, Wing Kam² 

[1] Univ Minnesota, Dept Civil Engn, Minneapolis, MN USA

[2] Northwestern Univ, Dept Mech Engn, Evanston, IL 60208 USA

关键词: Elasticity;    Microstructure;    Dispersion;    Damage;    Wave propagation;    Generalized continua;   

DOI  :  10.1016/j.ijsolstr.2012.06.011

来源: Elsevier

【 摘 要 】

This work combines closed-form and computational analyses to elucidate the dynamic properties, termed signatures, of waves propagating through solids defined by the theory of elasticity with microstructure and the potential of such properties to identify microstructure evolution over a material's lifetime. First, the study presents analytical dispersion relations and frequency-dependent velocities of waves propagating in microelastic solids. A detailed parametric analysis of the results show that elastic solids with microstructure recover traditional gradient elasticity under certain conditions but demonstrate a higher degree of flexibility in adapting to observed wave forms across a wide frequency spectrum. In addition, a set of simulations demonstrates the ability of the model to quantify the presence of damage, just another type of microstructure, through fitting of the model parameters, especially the one associated with the characteristic length scale of the underlying microstructure, to an explicit geometric representation of voids in different damage states. (C) 2012 Elsevier Ltd. All rights reserved.

【 授权许可】

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