Electro-osmotic chemical behavior of clayey soil under various boundary conditions  

不同边界条件下黏性土的电渗化学特性

作　　者：XUE Zhi-jia XIONG Qi 薛志佳;熊琦(School of Highway,Chang’an University,Xi’an 710064,China;State Key Laboratory of Coastal and Offshore Engineering,Dalian University of Technology,Dalian 116024,China)

机构地区：[1]School of Highway,Chang’an University,Xi’an 710064,China [2]State Key Laboratory of Coastal and Offshore Engineering,Dalian University of Technology,Dalian 116024,China

出　　处：《Journal of Central South University》2021年第5期1493-1504,共12页中南大学学报（英文版）

基　　金：Project(41902280)supported by the National Natural Science Foundation of China;Project(300102219105)supported by the Fundamental Research Funds for the Central Universities,China;Project(LP1922)supported by the Open Foundation of State Key Laboratory of Coastal and Offshore Engineering,China;Project(XJKFJJ201805)supported by the Open Foundation of Shaanxi Key Laboratory of Safety and Durability of Concrete Structures,China。

摘　　要：The use of electro-osmotic chemical is an effective method to improve the clayey soil foundation.Various boundary conditions can be adopted in this method.In this work,two electrode–clay contacts,three solution conditioners,and four anode solution supply times were used for clayey soil improvement.Based on the experimental data,electro-osmotic consolidation theory,and transport of ion theory,it is found that the electro-osmotic chemical effect of the separation of electrode–clay(E_S)is more beneficial for the transport of Ca^(2+),production of cementing material,and reduction of water content than that of electrode–clay(E_C)joining;through electrode–clay contact separation,the anode solution conditioner(NaPO3)6(E_SHMP)delayed the cementing reaction and then increased the transport of Ca^(2+)near the cathode,which increased the amount of cementing material and the electro-osmotic chemical effect;and when the anode conditioner(NaPO3)6 was used,two days of anode solution supply followed by three days cut off from the anode solution led to the highest undrained shear strength increase after the application of electro-osmotic chemical,which resolved the uneven electro-osmotic chemical effect in the E_SHMP.电渗化学法是加固黏性土地基的有效方法,可以对应使用多种边界条件。本文采用两种电极-黏土接触方式、三种溶液调节剂和四种阳极溶液供应不同时间对黏性土进行电渗化学加固。根据电渗化学实验数据、电渗固结理论和离子运移理论,得出如下结论,在电极-黏土分离方式下的电渗化学作用更有利于Ca^(2+)的运移、胶结材料的产生和黏土含水率的降低;依托电极-黏土分离方式,在阳极溶液中加入调节剂(NaPO3)6(E_SHMP)延缓了胶结反应,增加了阴极附近Ca^(2+)的运移,提高了胶结材料的产量,加强了电渗化学加固黏性土的效果;当使用阳极调节剂(NaPO3)6时,在供应2 d阳极溶液之后,切断阳极溶液并继续进行3 d电渗试验,获得的黏性土不排水抗剪强度值最高,并且解决了单纯电渗化学效果不均匀的问题。

关 键 词：electro-osmotic chemical boundary conditions clayey soil improvement electrode−clay contacts solution conditioner anode solution supply time 

分 类 号：TU442[建筑科学—岩土工程]