摘要
针对不同质量配比的膨润土-红黏土混合土压实样,开展不同浓度的NaCl溶液渗透试验;基于扩散双电层理论和土颗粒微观结构,分析溶液浓度对不同质量配比混合土渗透系数的影响机理;根据试验结果,建立混合土渗透系数与膨润土掺量(质量分数)的函数关系式。研究结果表明:混合土的渗透系数随着膨润土掺量的增加而降低,膨润土的加入明显提高了混合土的防渗和化学阻滞能力;随着溶液浓度提高,红黏土的絮凝程度增加,渗透系数降低;掺入质量分数为20%的膨润土后,随着溶液浓度提高,混合土扩散双电层被压缩,渗透系数相应增大。
The bentonite-laterite mixtures with different mass ratios of bentonite were compacted,and then permeability of the mixtures was tested for NaCl solutions with different concentrations.Based on theory of the diffuse double layer and micro-structure characteristics of soil particles,effect mechanism of salt solutions on permeability coefficient of the mixtures was analyzed.Furthermore,an empirical equation between saturated permeability and bentonite content(mass fraction)was established according to the tested results.The results show that saturated permeability of bentonite-laterite decreases with the increase of bentonite content,and thus retarding ability improves significantly.The infiltration of NaCl solution induces more flocculation,which decreases the permeability of laterite soil.For mixtures with 20%(mass fraction)bentonite,the permeability coefficient increases with the increase of salt concentration due to the compression of diffuse double layers.
作者
陈永贵
雷宏楠
贺勇
叶为民
CHEN Yonggui;LEI Hongnan;HE Yong;YE Weimin(Key Laboratory of Geotechnical and Underground Engineering of Ministry of Education,Tongji University,Shanghai 200092,China)
出处
《中南大学学报（自然科学版）》
EI
CAS
CSCD
北大核心
2018年第4期910-915,共6页
Journal of Central South University:Science and Technology
基金
国家自然科学基金资助项目(41772279)~~
关键词
压实黏土衬垫
红黏土
膨润土
盐溶液
渗透系数
compacted clay liner
laterite
bentonite
salt solution
hydraulic conductivity
作者简介
通信作者:陈永贵,博士(后),教授,博士生导师,从事环境地质工程及非饱和土力学研究;E-mail:cyg@tongji.edu.cn
