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arXiv · 1805.06024

A generalized anisotropic deformation formulation for geomaterials

Zhou Lei·Esteban Rougier·Earl E. Knight·Antonio Munjiza·Hari Viswanathan
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Abstract

In this paper, the Combined Finite-Discrete Element Method (FDEM) has been applied to analyze the deformation of anisotropic geomaterials. In the most general case geomaterials are both non-homogeneous and non-isotropic. With the aim of addressing anisotropic material problems, improved 2D FDEM formulations have been developed. These formulations feature the unified hypo-hyper elastic approach combined with a multiplicative decomposition-based selective integration for volumetric and shear deformation modes. This approach is significantly different from the co-rotational formulations typically encountered in finite element codes. Unlike the co-rotational formulation, the multiplicative decomposition-based formulation naturally decomposes deformation into translation, rotation, plastic stretches, elastic stretches, volumetric stretches, shear stretches, etc. This approach can be implemented for a whole family of finite elements from solids to shells and membranes. This novel 2D FDEM based material formulation was designed in such a way that the anisotropic properties of the solid can be specified in a cell by cell basis, therefore enabling the user to seed these anisotropic properties following any type of spatial variation, for example, following a curvilinear path. In addition, due to the selective integration, there are no problems with volumetric or shear locking with any type of finite element employed.

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BibTeXRIS

Zhou Lei, Esteban Rougier, Earl E. Knight, Antonio Munjiza, Hari Viswanathan. 2018-05-15. A generalized anisotropic deformation formulation for geomaterials. https://doi.org/10.1007/s40571-015-0079-y

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