Data/hora: 07/06/2024 11:07:10

Provedor de dados: | 42
País: | Brazil
Título: | Estimating vertical and lateral pressures in periodically structured montmorillonite clay particles
Autores: | Narsilio,Guillermo A.; Smith,David W.; Pivonka,Peter.
Data: | 2010-03-01
Ano: | 2010
Palavras-chave: | Clay; Maxwell tensor; Poisson-Nernst-Planck equation; Pore-scale; Swelling; Van't Hoff law.
Resumo: | Given a montmorillonitic clay soil at high porosity and saturated by monovalent counterions, we investigate the particle level responses of the clay to different external loadings. As analytical solutions are not possible for complex arrangements of particles, we employ computational micromechanical models (based on the solution of the Poisson-Nernst-Planck equations) using the finite element method, to estimate counterion and electrical potential distributions for particles at various angles and distances from one another. We then calculate the disjoining pressures using the Van't Hoff relation and Maxwell stress tensor. As the distance between the clay particles decreases and double-layers overlap, the concentration of counterions in the micropores among clay particles increases. This increase lowers the chemical potential of the pore fluid and creates a chemical potential gradient in the solvent that generates the socalled 'disjoining' or 'osmotic' pressure. Because of this disjoining pressure, particles do not need to contact one another in order to carry an 'effective stress'. This work may lead towards theoretical predictions of the macroscopic load deformation response of montmorillonitic soils based on micromechanical modelling of particles.
Tipo: | Info:eu-repo/semantics/article
Idioma: | Inglês
Identificador: | http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652010000100003
Editor: | Academia Brasileira de Ciências
Relação: | 10.1590/S0001-37652010000100003
Formato: | text/html
Fonte: | Anais da Academia Brasileira de Ciências  v.82 n.1 2010
Fonte: | info:eu-repo/semantics/openAccess