Field tests on liquefaction resistance of desaturation measure of electrolysis

The electrolytic desaturation method, as an innovative mitigation of soil liquefaction, is proposed in recent years. Liquefaction resistance can be improved by the air bubbles produced by electrolysis of the pore water inside the saturated sandy foundation. Desaturation tests are carried out under the constant current intensity with graphite used as the electrodes. Based on the compression wave velocity tests, the saturation of soil in the deep foundation is found to be reduced from 98.2 % to 94 % in the process of electrolysis. By focusing on the electrical properties of the foundation soil in the process of electrolysis, some results are obtained. Firstly, the equivalent resistance gradually increases with the decrease of saturation, which shows a good single value function. Secondly, with the increase of current intensity, the equivalent resistance of the growth rate is higher, and the resistance increases more quickly, meanwhile to achieve that the maximum power consumption of equivalent resistance increases gradually, and then tends to be gentle. During the process, a slight increase in power consumption caused by the increase of current intensity is balanced by significant improvement of the efficiency of desaturation measure of electrolysis. In addition, the attenuation process of equivalent resistance can be divided into 3 stages: rapid attenuation, smooth attenuation and stability. 3 h after cessation electrolysis is the rapid attenuation phase, and the equivalent resistance of the average decay rate is 11 Ω/h. Even though it is difficult to maintain bubbles between the electrodes in the long term due to seepage factor resulted from river test site, 15% drop of electric resistance in the rapid attenuation stage indicates that the liquefiable foundation can still maintain good liquefaction resistance. Then it can significantly save lots of power consumption by electrolyzing the liquefiable foundation twice or more times, which is about 30% of the first electrolysis. Furthermore, it can also accelerate the generation of bubbles between the positive and negative poles in the foundation soil. Thus, it can effectively reduce the saturation, and improve the efficiency of desaturation measure of electrolysis and the liquefaction resistance.