电渗过程中电极与土体间电荷积累问题研究

Abstract

In the process of electroosmosis, electric charges tend to accumulate along the interface between soil and electrode, which causes substantial voltage drop at the interface. In this study, the interface was simulated by a capacitor to account for the accumulation of electric charges. Governing equations were derived with respect to the electric current, effective voltage and voltage drop under the assumption that the capacitor of the interface and the resistor of soil mass were connected in series. The equations were verified by experimental results. It is indicated that the capacitor consists of electrode, tiny gap between soil and electrode, and soil mass. The capacitor is able to accumulate electric charges and thus consume electric potential at the interface of soil and electrode. The capacitance of a cylindrical electrode is greater than that of a plane electrode. = 电渗过程中的电荷积累现象是电极和土体界面间存在电压降的主要原因,将电荷积累区域视为一特殊电容器,模拟了土与电极界面间的电容效应,推导了界面电容与土体电阻串联后土体中的电压降、电容间距和孔隙水压力,通过圆柱形电极和电极板试验,验证了界面电容假设的合理性,同时指出随着电渗的进行,电荷积累增多,电压降增大,且圆柱形电极形成的电容大于电极板形成的电容。