A model for coupled electro-hydro-mechanical processes in fine grained soils accounting for gas generation and transport

作者：Tamagnini Claudio; Jommi Cristina^*; Cattaneo Fabio

来源：Anais da Academia Brasileira de Ciencias, 2010, 82(1): 169-193.

DOI：10.1590/S0001-37652010000100014

• electro-osmosis
• experimental investigation
• theoretical model
• finite element analysis
• unsaturated soils

A theoretical and numerical model is developed for the quantitative analysis of coupled processes taking place in active waste containment systems, such as electrokinetic barriers or fences, in which a low intensity DC current is circulated across the clay barrier to move polar and non-polar contaminants. A novel feature of the proposed approach is the allowance for the presence of air in the pore space. Under unsaturated conditions, all transport coefficients involved in the electrokinetic process are strongly dependent on the degree of saturation of pore liquid. In order to assess the predictive capability of the proposed theory and to appreciate the impact of gas production at the electrodes, a series of numerical simulations of simple one-dimensional electrokinetic tests have been performed. The results of the simulations compare reasonably well with data obtained from laboratory experiments performed on an illitic clayey silt. The numerical results indicate that the impact of gas production at the electrodes can be significant, even in low-intensity and short-duration treatments.

• 出版日期2010-3