电极处加入CaCl2溶液对高岭土电渗试验的影响

为了研究高岭土电渗过程中在电极处加入CaCl₂溶液对电流、排水量、界面电阻、土体电阻率及最终抗剪强度等的影响,开展了相关室内试验。结果表明:电极处加入CaCl₂溶液后,电流的减小趋势得到有效控制,电渗过程中电流大小与加入CaCl₂溶液的量有关,也可能与阳极所加CaCl₂溶液所占比例或者与CaCl₂溶液加入的时间有关;排水量变大,本试验条件下电渗排水量提高了10.9%;电极处加入CaCl₂溶液对阴极处界面电阻的减小很明显;电极处加入CaCl₂溶液后土体总电阻率下降较为明显,而阴极附近土体电阻率的下降对土体总电阻率下降起主要贡献;阳极和中部土体最终抗剪强度提高比较明显,尤其是阳极土体最终抗剪强度提高了16.4 kPa,但阴极土体抗剪强度无明显提高,因此可以考虑用反转电极的方法来加固阴极土体。该研究可为高岭土电渗试验提供新思路。

Influences of CaCl2 Solution Added to Electrodes on the Electro-osmotic Test of Kaolin Clay

The changes of electricity current,water discharge,interfacial resistance and final shear strength after CaCl2 solution was added to electrodes during the electro-osmosis of kaolin clay were studied through laboratory test.Results show that adding CaCl2 solution to the electrodes could effectively control the decrease of current in soil,and the current strength is not only related to the amount of added CaCl2 solution,but probably also to the proportion of CaC12 solution added to the anode,or the time when the CaCl2 solution is added.Displacement becomes larger,improving by 10.9％ under the condition of the present experiment.The decrease of interfacial resistance of anode is obvious.The total resistivity of the kaolin soil declines obviously with the resistivity decline of the soil near cathode making the main contribution.Moreover,the average shear strength near anode and in the middle of the soil increases obviously,especially the average shear strength near anode of the soil increases by 16.4 kPa;whereas the average shear strength of the soil near the cathode does not increase.Therefore,reversing the electrodes could be an approach of electro-osmosis test on kaolin soil near the cathode.