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arXiv · 1007.2338

A Variational Deduction of Second Gradient Poroelasticity Part I: General Theory

Giulio Sciarra·Francesco dell'Isola·Nicoletta Ianiro·Angela Madeo
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Abstract

Second gradient theories have to be used to capture how local micro heterogeneities macroscopically affect the behavior of a continuum. In this paper a configurational space for a solid matrix filled by an unknown amount of fluid is introduced. The Euler-Lagrange equations valid for second gradient poromechanics, generalizing those due to Biot, are deduced by means of a Lagrangian variational formulation. Starting from a generalized Clausius-Duhem inequality, valid in the framework of second gradient theories, the existence of a macroscopic solid skeleton Lagrangian deformation energy, depending on the solid strain and the Lagrangian fluid mass density as well as on their Lagrangian gradients, is proven.

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Giulio Sciarra, Francesco dell'Isola, Nicoletta Ianiro, Angela Madeo. 2010-07-14. A Variational Deduction of Second Gradient Poroelasticity Part I: General Theory. https://arxiv.org/abs/1007.2338

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