不同矿物成分下土样脱附曲线试验研究  

Experimental research on desorption curves of soil samples under different mineral compositions

作　　者：朱赞成[1] 李纪伟 林法力 陈雰[1] 孙德安[2] 刘藤 ZHU Zan-cheng;LI Ji-wei;LIN Fa-li;CHEN Fen;SUN De-an;LIU Teng(School of Civil Engineering and Architecture,Taizhou University,Taizhou 318000,China;Department of Civil Engineering,Shanghai University,Shanghai 200072,China)

机构地区：[1]台州学院建筑工程学院,浙江台州318000 [2]上海大学土木工程系,上海200072

出　　处：《岩土工程学报》2020年第1期175-180,共6页Chinese Journal of Geotechnical Engineering

基　　金：国家自然科学基金项目（11672172）;台州市科技项目（1702gy09）;浙江省自然科学基金项目（LY19E080007）

摘　　要：精确测定土样含水率的数值对于研究高吸力时非饱和土的土水特性尤为重要。目前国内外现有土工规范在测定土样含水率时均设定恒温箱温度为110℃,鲜少有文献对该温度设定的合理性进行研究。利用同步热分析仪对高庙子膨润土、高岭土、台州滨海软黏土等7种不同类型的黏土进行了微商热重法分析(DTG)和热重分析(T-G),同时对这7种黏土,用X射线衍射仪(XRD)测试了其矿物成分。试验结果显示随着土样中含蒙脱石矿物质量百分数的增加,其失去吸附水的温度越高;而当土样中不含蒙脱石矿物成分,土样的失去吸附水的温度比较低。认为对于蒙脱石含量较高的土样,测定含水率时,应将烘箱的温度由110℃提高150℃。The accurate determination of water content for soils is particularly important for studying the soil-water characteristics of unsaturated soils with high suction range. At present, the oven temperature is set at 110℃ in the standards of soil testing method at home and abroad. Few literatures have studied the rationality of the temperature setting. Here, seven different types of clays, Na and Ca-Gaomiaozi bentonites, Shanghai soft clay, kaolin and Taizhou coastal soft clay, are analyzed by derivative thermogravimetry(DTG) and thermogravimetric analysis(T-G) with synchronous thermal analyzer. At the same time, their mineral compositions are tested by the X-ray diffraction(XRD). The test results show that the higher the mass percentage of montmorillonite minerals in soil samples, the higher the temperature of losing adsorbed water. When there is no montmorillonite mineral composition in soil samples, the temperature of losing adsorbed water is lower. It is considered that the oven temperature should be raised from 110 to 150 ℃ for measuring the water content of soil samples with high montmorillonite content.

关 键 词：持水性 含水率 层间水化 

分 类 号：TU43[建筑科学—岩土工程]