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J4  2013, Vol. 47 Issue (9): 1579-1584    DOI: 10.3785/j.issn.1008-973X.2013.09.010
    
Experimental research on effect of polarity reversal to electro-osmotic
CHEN Zhuo 1,2 , ZHOU Jian1, WEN Xiao-gui1,TAO Yan-li1
1. Key Laboratory of Soft Soil and Geoenvironmental Engineering, Zhejiang University, Hangzhou 310058, China;
2. Tianjin Key Laboratory of Soft Soil Characteristics and Engineering Environment, Tianjin 300384, China
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Abstract  

A series of one-dimensional electro-osmotic laboratory tests on Hangzhou soft clay were conducted in a self-made tank to investigate the efficiency of polarity reversal. In order to compare the differences between normal electro-osmotic and adoption of polarity reversal technique, and to find out the way how reversal frequency affects electro-osmotic, four different reversal frequencies were included: 1 h, 5 h, 15 h, no reversal. Current density and drainage were monitored at set intervals during the test, and the distributions of shear strength, and water content as well as the variation of soil resistance and contact resistance with time were analyzed. Results show that the current rises slightly then reduces sharply after every time of polarity reversal, moreover, the new cathode needs a waiting time to dewatering, which leads to lower drainage than that of normal electro-osmosis|although the polarity reversal technique contributes to the uniformity of soil properties and deformation, it is not superior to normal electro-osmotic because of the worse results about shear strength|in addition, the higher frequency adopted, the worse result displays. The main reason for these results is that this technique leads to the rapid rise in contact resistances, which reduces the current and finally slows the efficiency of electro-osmotic down.
 



Published: 01 September 2013
CLC:  TU 443  
Cite this article:

CHEN Zhuo , ZHOU Jian, WEN Xiao-gui,TAO Yan-li. Experimental research on effect of polarity reversal to electro-osmotic. J4, 2013, 47(9): 1579-1584.

URL:

http://www.zjujournals.com/eng/10.3785/j.issn.1008-973X.2013.09.010     OR     http://www.zjujournals.com/eng/Y2013/V47/I9/1579


电极反转对电渗加固效果的试验研究

采用自制模型箱,针对杭州软黏土进行一维电渗试验来探讨电极反转对电渗加固的影响.根据反转周期将试验分为4组:1 、5 、15 h、不反转.观察不同反转周期下电渗的特点,并与常规电渗效果进行对比,进而探讨电极反转的有效性.定期测量试验过程中的电流和排水量,计算土体电阻和界面电阻随时间的变化;并给出试验结束时的含水量、抗剪强度空间分布图.试验过程中发现,每次反转电极,电流均呈现略微上升之后又迅速降低,同时排水不会马上继续而需要等待时间,这使得电极反转组的排水效果要较常规电渗差.试验结果表明:电极反转虽然使得土体固结变形较为均匀,但是平均抗剪强度却较常规电渗差;反转周期越短,效果越差,其主要原因是电极反转会导致界面电阻急剧增大,电流降低过快,从而影响电渗效率.

[1] 李 瑛,龚晓南. 软黏土地基电渗加固的设计方法研究[J].岩土工程学报,2011,33(6):955-959.
LI Ying, GONG Xiao-nan. Design method of electro-osmotic reinforcement for soft clay foundations[J]. Chinese Journal of Geotechnical Engineering, 2011,33(6):955-959.
[2] 李 瑛. 软黏土地基电渗固结试验和理论研究[D]. 杭州:浙江大学,2011:8142.
LI Ying. Experimental and theoretic study on electro-osmotic consolidation of soft clay foundation [D]. Hangzhou: Zhejiang University, 2011: 8142.
[3] WAN T Y, MITCHELL J K. Electro-Osmotic Consolidation of Soils [J]. Journal of Geotechnical Geotechnical Division, ASCE, 1976, 102(5): 473-491.
[4] LO K Y, HO K S. The effects of electroosmotic field treatment on the soil properties of a soft sensitive clay[J]. Canadian Geotechnical Journal, 1991, 28(6): 763-770.
[5] SHANG J Q. Electrokinetic dewatering of clay slurries as engineered soil covers[J].Canadian Geotechnical Journal,1997, 34:78-86.
[6] 王协群, 邹维列. 电渗排水法加固湖相软黏土的试验研究[J]. 武汉理工大学学报, 2007, 29(2): 95-99.
WANG Xie-qun, ZOU Wei-lie. Experimental research on electro-osmotic consolidation of lacustrine clay[J].Journal of Wuhan University of Technology, 2007, 29(2): 95-99.
[7] OU Chang-yu, CHIEN Shao-chi, CHANG Hsuan-hsiang. Soil improvement using electroosmosis with the injection of chemical solutions: field tests[J].Canadian Geotechnical Journal, 2009, 46:727-733.
[8] MICIC S, SHANG J Q, LO K Y. Electrokinetic strengthening of marine clay adjacent to offshore foundations[C]∥Proceedings of the Eleventh international Offshore and Polar Engineering Conference. Stavanger , Norway: [s. n.], 2001:694-701.
[9] YOSHIDA H, KITAJYAO K, NAKAYAMA M. Electroosmotic dewatering under A.C. electric field with periodic reversals of electrode polarity[J]. Drying Technology, 1999, 17(3): 539-554.
[10] 李 瑛, 龚晓南, 张雪婵. 电压对一维电渗排水影响的试验研究[J]. 岩土力学, 2011, 32(3): 709-714.
LI Ying, GONG Xiao-nan, ZHANG Xue-chan. Experimental research on effect of applied voltage on one-dimensional Electroosmotic drainage[J]. Rock and Soil Mechanics, 2011, 32(3): 709-714.
[11] 庄艳峰, 王钊. 电渗固结中的界面电阻问题[J]. 岩土力学, 2004, 25(1): 117-120.
ZHUANG Yan-feng, WANG Zhao. Study on interface electric resistance of electro-osmotic consolidation[J]. Rock and Soil Mechanics, 2004, 25(1): 117-120.
[12] 胡黎明, 洪何清, 吴令伟. 高岭土的电渗试验[J]. 清华大学学报, 2010, 50(9): 1353-1356.
HU Li-ming, HONG He-qing, WU Ling-wei. Electro-osmotic tests on kaolin clay[J]. Journal of Tsinghua University, 2010, 50(9): 1353-1356.

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