分散性土分类与鉴别的室内试验研究  

Laboratory Test of Classification and Identification for Dispersive Clay

作　　者：岳婵 唐红[1] 姚海林[2] 刘杰 杨玉婳 YUE Chan;TANG Hong;YAO Hailin;LIU Jie;YANG Yuhua(Institute of Urban Construction,Wuhan University of Science and Technology,Wuhan 430065,China;State Key Laboratory of Geomechanics and Geotechnical Engineering,Institute of Rock and Soil Mechanics,CAS,Wuhan 430071,China)

机构地区：[1]武汉科技大学城市建设学院,湖北武汉430065 [2]中国科学院武汉岩土力学研究所岩土力学与工程国家重点实验室,湖北武汉430071

出　　处：《人民黄河》2021年第7期149-153,159,共6页Yellow River

基　　金：国家自然科学基金资助项目(41672312)。

摘　　要：采取5项土样的分散性鉴别试验,即针孔试验、双比重计试验、碎块试验、孔隙水可溶性阳离子试验和交换性钠离子百分比试验,以及标准吸湿含水率和pH值的测定,对东北某大坝心墙土料进行分散性鉴定试验研究。试验和分析结果表明,10个土壤样品中,3个呈分散性,1个呈过渡性,其余6个呈非分散性。通过分析土壤样品的理化特性发现:3个分散性土壤样品发生分散的主要原因是交换性钠离子含量较高,pH值较高,属于强碱性土壤;另外7个土样中的黏粒含量和有机质含量高,pH值偏低,抑制了分散性,因此土样表现为不分散或过渡性土的特征。标准吸湿含水率试验能较为准确地测定出土样中的蒙脱石含量,再结合pH值和交换性钠离子百分比试验,可对土样的分散性进行初步推测。The dispersibility of soil samples obtained from the core wall of dam in the northeast area of China was studied by the chemical properties of soil analysis and the tests for identification of dispersive clay soils.The tests included double⁃hydrometer test,pinhole test,crumb test,the test to determine salt contents of pore water and percentage of exchangeable sodium,standard moisture absorption water con⁃tent and pH.The results of experiments and analysis show that three soil samples are dispersive type,one is transition and six are non⁃disper⁃sive by the five test methods.These three dispersive soil samples contain a large amount of exchangeable sodium,have rather high pH values and indicate strongly alkaline,which can promote dispersivity.Their high contents of clay,organic matter and low pH values and lower dis⁃persivity have inhibited dispersion,showing transitional and non⁃dispersive characteristics.The amount of montmorillonite can be detected by the standard moisture absorption water content accurately,combining pH and exchangeable sodium can predict the dispersion of soil prelimi⁃narily.

关 键 词：分散性土 标准吸湿含水率 酸碱度 蒙脱石 交换性钠离子 

分 类 号：TV443[水利工程—水工结构工程]