温度对高液限土吸附结合水及其变形影响的试验研究
Experimental Study on Effect of Temperature on Bound Water Adsorption and Deformation of High Liquid Limit Soil
訾银辉 1申姁宁 2张浩 1张锐 2李露2
作者信息
- 1. 海南省交通工程建设局,海南 海口 570208
- 2. 长沙理工大学 交通运输工程学院,湖南 长沙 410114
- 折叠
摘要
为研究温度变化对高液限黏土吸附结合水含量的影响及高液限黏土路堤的变形规律,该文选取海南高液限黏土为主要研究对象,并与湖南低液限砂土进行对比研究.通过核磁共振试验,探究温度对高液限黏土吸附结合水含量的影响规律;通过温控固结仪开展固结试验,分析温度对高液限黏土路堤变形的影响规律;借助分子动力学模拟软件,从微观层面探究温度对高岭石吸附水分子影响机制.结果表明:温度由5℃上升至45℃,高液限黏土中吸附结合水减少4.3个百分点,远大于低液限砂土减少量(1.4个百分点).恒定温度、相同荷载路径下,高液限黏土孔隙比随温度升高变化较大,而低液限砂土几乎不受影响,说明高液限黏土温敏性更强.恒定压力下,温度升高对高岭石吸附水有削弱作用;相同的升温路径下,压力越大高岭石吸附的水分子量越多.
Abstract
In order to study the effect of temperature change on the bound water content adsorbed by high liquid limit clay and the deformation law of high liquid limit clay embankment,the high liquid limit clay in Hainan Province was selected as the primary research object and compared with the low liquid limit sand in Hunan Province.The effect of temperature on the bound water content adsorbed by high liquid limit clay was explored through a nuclear magnetic resonance test.In addition,the effect of temperature on the deformation of high liquid limit clay embankments was analyzed through the consolidation test with a temperature-controlled consolidometer.The molecular dynamics simulation software was used to reveal the mechanism of temperature affecting water adsorption by kaolinite from the microscopic level.The results show that when the temperature rises from 5℃ to 45℃,the bound water adsorbed by high liquid limit clay decreases by 4.3 percentage points,much greater than that adsorbed by low liquid limit sand(a decrease by 1.4 percentage points).Under constant temperature and the same load path,the pore ratio of high liquid limit clay changes significantly with the temperature increase.In contrast,low liquid limit sand is almost unaffected,indicating that high liquid limit clay is more temperature-sensitive.The rise in temperature under constant pressure can weaken water adsorption by kaolinite.Under the same heating path,higher pressure indicates more water adsorbed by kaolinite.
关键词
高液限黏土/温度/吸附结合水/变形特性Key words
high liquid limit clay/temperature/bound water adsorption/deformation characteristics引用本文复制引用
基金项目
国家自然科学基金资助项目(52278432)
国家自然科学基金资助项目(51978085)
海南省地方标准制修订项目(2021-Z043)
出版年
2024
国家科技期刊平台
NSTL
万方数据