变单向压力下重塑膨胀土膨胀试验研究  

Experimental study on swelling characteristics of remolded expansive soil under uniaxial pressure

作　　者：孙刚臣[1,2,3] 刘锋[2,3] 刘宝臣[2,3] 

机构地区：[1]长安大学地质工程与测绘工程学院,陕西西安710054 [2]广西岩土力学与工程重点实验室,广西桂林541004 [3]桂林理工大学土木与建筑工程学院,广西桂林541004

出　　处：《广西大学学报（自然科学版）》2015年第4期969-977,共9页Journal of Guangxi University（Natural Science Edition）

基　　金：广西科技攻关与新产品试制项目(桂科攻0992027-8)

摘　　要：为了研究胀限与变单向压力和初始含水率、三向膨胀率与变单向压力和初始含水率的关系，用“膨胀土三向胀缩测试仪”对广西宁明灰白重塑膨胀土进行了三向等压（27 kPa）的情况下变单向压力（27~164 kPa）的膨胀增湿试验。对试验数据进行拟合、对比分析得出：胀限可与变单向压力的对数进行线性拟合，胀限由三向压力决定，与初始含水率无关；无论水平向压力还是竖直向压力，均会抑制该向的膨胀变形，该向膨胀可与该向压力的对数进行一次线性拟合；三向中任一向加压都会同时促进另外两向膨胀变形，该向压力越大，对另外两向膨胀变形的促进作用越大；相同压力条件下，三向膨胀率均与初始含水率呈一次线性负相关；当竖直向压力为水平向压力的2倍时，各向膨胀率与初始含水率关系曲线基本重合。In order to investigate the influence of varying unidirectional pressure and initial water content on the expansion limit and the three-directional swelling ratio, a hygral expansion test for the remolded gray expansive soil from Ningming, Guangxi under varying unidirectional pressure （27~164 kPa） was performed in the condition of equal pressure （27 kPa） in the three directions using the “three-directional swelling shrinkage tester for expansive soil”. Some results are obtained by fit-ting and analyzing the experimental data. The results indicate that the expansion limit is determined by the three-directional pressure, which is irrelevant to the initial water content. The raising of pres-sure in either direction will promote the expansion deformation in other directions, and the expansion deformation can be fitted linearly with the logarithm of the varying unidirectional pressure. The grea-ter the pressure is, the more promotion to the expansion deformation in other two directions will be.＆amp;nbsp;Under the same pressure, the three-directional expansion-rate and initial water content was negative-ly related. When the vertical pressure becomes 2 times of the horizontal pressure, the relation curves between the expansion rate and initial water content basically coincides.

关 键 词：变单向压力 重塑膨胀土 胀限 膨胀变形 线性拟合 

分 类 号：TU411.8[建筑科学—岩土工程]