Analytical solution of vacuum preloading technology combined with electroosmosis coupling considering impacts of distribution of soil’s electrical potential

Abstract

Combining vacuum preloading technology and electroosmosis can improve the treatment effect of soft soil foundation by utilizing the advantages of both methods. Many studies indicate that the soil electrical potential is non-linearly distributed in the treatment process by the combined method. However, in the previous theoretical study, the non-linear-distribution impacts of soil’s electrical potential on soft soil foundation treatment have not been considered. It is always assumed to be linear distribution, which is different from the experimental results. In this paper, the coupling consolidation model of this technology under the two-dimensional plane strain condition is initially established; and the well resistance effect, the vacuum load decreasing along the soil depth and the non-linear variation of electrical potential in the soil are considered. Then, the analytical solutions of the average excess pore water pressure and soil’s consolidation degree in the anode affected area are acquired based on the soil’s electrical potential distribution. Finally, the rationality of the analytical solution is testified by conducting an experimental model test, which proves the scientificity of the analytical solution. The analytical solution is adopted to better predict the dissipation of excess pore water pressure and soil consolidation degree when using the combined technology. This study can provide a reference with more accuracy for the engineering practices of this combined technology in the future.

Keywords

vacuum preloading-electroosmosis / non-linear distribution / 2D plane strain / coupling consolidation model / pore water pressure

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