电压对一维电渗排水影响的试验研究

Experimental research on effect of applied voltage on one-dimensional electroosmotic drainage

在自制的模型箱中进行一维电渗排水试验,通过监测排水量、电势分布、含水率和电流来研究不同电源电压对电渗排水的影响。试验结果表明:较大的电压会导致排出单位体积水所需的能量消耗较高;较大的电压和较短的电渗时间会导致土体含水率分布异常,两极中间最高,阳极附近最低;排水量的逐渐减小是因为电极接触电阻的增大和电渗渗透系数的减小;电极和土体接触面上存在的接触电阻使得实际用于电渗的电压小于电源输出电压,而且电源电压越大,阳极接触电阻随电渗时间增加的速率越快,但是阴极接触电阻在高电压时缓慢增长,在低电压时迅速增大,而这与电渗排水速率有关。

A laboratory test program was conducted in a self-made test tank to investigate one-dimensional electroosmotic drainage at different supply voltages.By monitoring drainage,voltage profile,water content and current intensity every one hour during the entire test period,results below were acquired： higher voltage would lead larger energy consumption per unit volume drainage;the combination of higher voltage and shorter electroosmosis time would cause the abnormal moisture distribution that the highest was in the middle of electrodes and the lowest was near anode;the gradually decreasing of drainage was because of the increasing electrode contact resistances and the decreasing electroosmotic permeability coefficient;the contact resistance existing on the interface of soil and electrode made the voltage used for electroosmotic drainage lower than the supply voltage;and the higher voltage lead the larger anode contact resistance,but the condition in cathode was different that slow increasing occurred at higher voltage and fast increasing at lower.They related to electroosmotic drainage rate which determined mainly by supply voltage.