南宁灰白重塑膨胀土三向膨胀室内试验研究  

Laboratory Test and Research on Three-way Expansion of Grey-white Remolded Expansive Soil in Nanning

作　　者：谭波[1,2] 徐良[2] 李亚奇 TAN Bo;XU Liang;LI Ya-qi(Guangxi Key Laboratory of Geomechanics and Geotechnical Engineering,Guilin University of Technology,Guilin University of Technology,Guilin 541004,China;College of Civil and Architectural Engineering,Guilin University of Technology,Guilin 541004,China)

机构地区：[1]桂林理工大学广西岩土力学与工程重点实验室,桂林541004 [2]桂林理工大学土木与建筑工程学院,桂林541004

出　　处：《科学技术与工程》2020年第35期14612-14618,共7页Science Technology and Engineering

基　　金：国家自然科学基金(51768015);广西自然科学基金(2017GXNSFAA198092)。

摘　　要：膨胀土是一种具有强胀缩性的特殊黏土,掌握其三向膨胀规律对于合理分析膨胀土边坡变形失稳具有重要意义。以南宁灰白膨胀土为试验对象,开展不同条件下的三向膨胀率和膨胀力试验,揭示了干密度、初始含水率和外部荷载对于膨胀率和膨胀力的影响规律。试验表明,三向膨胀率和膨胀力均表现为:两个水平方向基本一致,竖向大于水平方向;干密度相同时,均随初始含水率的增大而减小,初始含水率相同时,均随初始干密度的增大而增大;膨胀率横、竖向比值均随干密度和初始含水率的增大越趋近于1;三向膨胀率均与三向荷载呈对数线性关系,荷载对膨胀具有抑制作用;横向膨胀力与控制横向膨胀率有良好的指数关系,说明土体膨胀力将因为膨胀变形释放而大幅减小。Expansive soil is a special clay with strong swelling and shrinking properties.It is of great significance to master the law of three-way expansion for the rational analysis of deformation and instability of expansive soil slope.Taking Nanning gray-white expansive soil as the test object,three-way expansion rate and expansion force tests under different conditions were carried out.The influence of dry density,initial moisture content and external load on the expansion rate and expansion force was revealed.Tests show that the law of three-way swelling rate and swelling force.Their horizontal directions are basically the same,the vertical direction is greater than the horizontal direction.Both the swelling rate and swelling force decrease with the increase of the initial water content when the dry density is the same,and increase with the increase of the initial dry density when the initial water content is the same.The lateral and vertical ratios of the swelling ratio both approach to 1 with the increase of the dry density or the initial moisture content.The three-way expansion rate is logarithmically linear with the three-way load,and the load has an inhibitory effect on the expansion.The lateral expansion force and the control lateral expansion rate have a good exponential relationship,indicating that the expansion force of the soil will be greatly reduced due to the expansion deformation.

关 键 词：膨胀土 膨胀土三向膨胀仪 膨胀率 膨胀力 控制变形的膨胀力试验 

分 类 号：TU443[建筑科学—岩土工程]