Bending of a poroelastic beam with lateral diffusion

George W. Scherer, Jean H. Prévost, Zhihua Wang

Research output: Contribution to journalArticle

20 Citations (Scopus)

Abstract

Bending an elastic beam leads to a complicated 3D stress distribution, but the shear and transverse stresses are so small in a slender beam that a good approximation is obtained by assuming purely uniaxial stress. In this paper, we demonstrate that the same is true for a saturated poroelastic beam. Previous studies of poroelastic beams have shown that, to satisfy the Beltrami-Michell compatibility conditions, it is necessary to introduce either a normal transverse stress or shear stresses in addition to the bending stress. The problem is further complicated if lateral diffusion is permitted. In this study, a fully coupled finite element analysis (FEA) incorporating the lateral diffusion effect is presented. Results predicted by the "exact" numerical solution, including load relaxation, pore pressure, stresses and strains, are compared to an approximate analytical solution that incorporates the assumptions of simple beam theory. The applicability of the approximate beam-bending solution is investigated by comparing it to FEA simulations of beams with various aspect ratios. For "beams" with large width-to-height ratios, the Poisson effect causes vertical deflections that cannot be neglected. It is suggested that a theory of plate bending is needed in the case of poroelastic media with large width-to-height ratios. Nevertheless, use of the approximate solution yields very small errors over the range of width-to-height ratios (viz., 1-4) explored with FEA.

Original languageEnglish (US)
Pages (from-to)3451-3462
Number of pages12
JournalInternational Journal of Solids and Structures
Volume46
Issue number18-19
DOIs
StatePublished - Sep 2009
Externally publishedYes

Fingerprint

Lateral
Finite element method
shear stress
Finite Element
Pore pressure
elastic bending
Transverse
beam leads
Stress concentration
Shear stress
Aspect ratio
Loads (forces)
Plate Bending
Compatibility Conditions
compatibility
Stress Distribution
stress distribution
Simulation Analysis
aspect ratio
Shear Stress

Keywords

  • Beams and columns
  • Finite elements
  • Porous material
  • Strain compatibility
  • Stress relaxation

ASJC Scopus subject areas

  • Mechanical Engineering
  • Mechanics of Materials
  • Materials Science(all)
  • Condensed Matter Physics
  • Applied Mathematics
  • Modeling and Simulation

Cite this

Bending of a poroelastic beam with lateral diffusion. / Scherer, George W.; Prévost, Jean H.; Wang, Zhihua.

In: International Journal of Solids and Structures, Vol. 46, No. 18-19, 09.2009, p. 3451-3462.

Research output: Contribution to journalArticle

Scherer, George W. ; Prévost, Jean H. ; Wang, Zhihua. / Bending of a poroelastic beam with lateral diffusion. In: International Journal of Solids and Structures. 2009 ; Vol. 46, No. 18-19. pp. 3451-3462.
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