標題: Micromechanics model for elastic stiffness of non-spherical granular assembly
作者: Dong, JJ
Pan, YW
土木工程學系
Department of Civil Engineering
關鍵字: micromechanics model;granular assembly;elastic stiffness;fabric;inherent anisotropy;stress-induced anisotropy
公開日期: 1-九月-1999
摘要: This paper presents a micromechanics model for the elastic stiffness of a non-spherical granular assembly. The microstructural continuum model of ideal spherical assembly is extended for non-ideal assembly. The presented work takes the effects of gradation, shape, and preferred orientation into account by introducing a directional distribution function of branch-vector length. The microstructure of a granular assembly is described by the distributions of packing structure, branch-vector length, and particle number per unit volume. These distributions account or the random nature of a realistic granular material. The microfeatures relevant to the description of non-deal particle assembly are elaborated. The influences of various direction-dependent and direction-independent microfeatures on the elastic stiffness are demonstrated. Hypothetical non-ideal granular assemblies are used to study the effects of gradation, shape and preferred orientation. Based on the proposed model, the paper discusses the inherent anisotropy in a non-ideal granular assembly. The presented work also makes use of a generalized static hypothesis to estimate the contact-force distribution for specific microstructure and stress state. With the estimated contact-force and the Hertz-Mindlin contact theory, the elastic stiffness of a particulate assembly can be evaluated. Hence, the effects of geometric fabric and anisotropic stress state on the elastic stiffness can be deliberated. Consequently, the effects of geometric fabric and kinetic fabric of a natural granular material can be evaluated independently. It is shown that the proposed model can reasonably capture the phenomena of inherent anisotropy and stress-induced anisotropy of a non-spherical granular assembly under small strain. Copyright (C) 1999 John Wiley & Sons, Ltd.
URI: http://hdl.handle.net/11536/31138
http://dx.doi.org/10.1002/(SICI)1096-9853(199909)23:11<1075
ISSN: 0363-9061
DOI: 10.1002/(SICI)1096-9853(199909)23:11<1075
期刊: INTERNATIONAL JOURNAL FOR NUMERICAL AND ANALYTICAL METHODS IN GEOMECHANICS
Volume: 23
Issue: 11
起始頁: 1075
結束頁: 1100
顯示於類別:期刊論文


文件中的檔案:

  1. 000082795700001.pdf