不同介质环境条件下黏性土的分散性及其微观结构  

Dispersion and microstructure of clayey soil in different medium environments

作　　者：樊恒辉[1] 路立娜[1] 李洪良 赵高文[1] 卢雪清[1] 

机构地区：[1]西北农林科技大学水利与建筑工程学院,陕西杨凌712100 [2]山东昌乐县建筑工程质量监督站,山东昌乐262400

出　　处：《水力发电学报》2013年第4期193-198,共6页Journal of Hydroelectric Engineering

基　　金：国家自然科学基金(50979094);"十二五"国家科技支撑计划项目(2011BAD31B05);西北农林科技大学基本科研业务费(ZD2013013)

摘　　要：采用碎块试验、双比重计试验、电动电位、扫描电镜等测试方法,对典型的分散性土和非分散性土在不同介质环境条件下的分散性及其微观结构特征进行了研究。研究表明,介质环境中的钠离子含量和pH值高低是决定土体是否产生分散的本质因素,两种因素缺一不可。如果土体中含有大量的钠离子,并且酸碱度呈强碱性,则土体具有分散性。通过掺加高价阳离子和酸性物质,降低土体中钠离子的相对含量和酸碱度,可对分散性土进行改良。在自然沉积条件下,分散性土的微观结构中含有较多的孔隙;而非分散性土比较密实,孔隙较少。Dispersion and microstructure of non-dispersive and dispersive soils in different medium environments were studied using methods of crumb test, double hydrometer test, zeta electrical potential and scanning electron microscope. This study shows that the sodium ion and pH value of the medium environments are two essential and indispensable factors in determination of soil dispersion. If a soil contains much sodium ions and is alkaline in pH value, it will be dispersive. Dispersive soil can be improved by adding high valence ions and acid materials to reduce its relative sodium content and pH value. Under natural deposition, there exist more pores in dispersive soil than non-dispersive soil.

关 键 词：水工材料 分散机理 微观结构 分散性土 介质环境 ζ电动电位 

分 类 号：TV443[水利工程—水工结构工程]