Electro-osmotic chemical behavior of clayey soil under various boundary conditions

Abstract

The use of electro-osmotic chemical is an effective method to improve the clayey soil foundation. Various boundary conditions can be adopted in this method. In this work, two electrode-clay contacts, three solution conditioners, and four anode solution supply times were used for clayey soil improvement. Based on the experimental data, electro-osmotic consolidation theory, and transport of ion theory, it is found that the electro-osmotic chemical effect of the separation of electrode-clay (E_S) is more beneficial for the transport of Ca²⁺, production of cementing material, and reduction of water content than that of electrode-clay (E_C) joining; through electrode-clay contact separation, the anode solution conditioner (NaPO₃)₆ (E_SHMP) delayed the cementing reaction and then increased the transport of Ca²⁺ near the cathode, which increased the amount of cementing material and the electro-osmotic chemical effect; and when the anode conditioner (NaPO₃)₆ was used, two days of anode solution supply followed by three days cut off from the anode solution led to the highest undrained shear strength increase after the application of electro-osmotic chemical, which resolved the uneven electro-osmotic chemical effect in the E_SHMP.

Keywords

electro-osmotic chemical / boundary conditions / clayey soil improvement / electrode—clay contacts / solution conditioner / anode solution supply time

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