考虑体积变化修正的红黏土土水特征曲线试验研究  

Experimental Study on Soil Water Characteristic Curve of Laterite with Volume Change Correction

作　　者：陈浩 

机构地区：[1]湖南省永龙高速公路建设开发有限公司,湖南永顺416700

出　　处：《公路工程》2016年第5期97-101,共5页Highway Engineering

基　　金：交通部交通运输部建设科技项目(2014318785090);湖南省交通科技项目(201451)

摘　　要：红黏土是一种具有高度水敏性的典型特殊土,土水特征曲线(SWCC)是研究红黏土工程性质的重要依据,而红黏土在含水率变化时会发生明显的胀缩效应,现有SWCC测试往往缺乏对此效应的考虑,导致所测得的结果具有一定的误差。通过压力板仪法和滤纸法,量测了湖南某地区红黏土在不同含水率下所对应的基质吸力,并根据收缩试验掌握了红黏土在不同含水率下的体积变化特征并获取了相应的收缩系数,推导了体积变化修正公式,对SWCC进行了体积变化修正。结果表明:红黏土在含水率改变时的体积变化对其SWCC影响很大,同一基质吸力状态下,体积变化修正后红黏土试样的体积含水率和饱和度明显高于修正前的值,且基质吸力越高该差别越明显。[ Abstract] Laterite is a typical special soil which has high water sensitivity. Soil water characteristic curve（SWCC）is an important basis for studying engineering performance of laterite. However, laterite has obvious swell-shrink effect when the moisture changes. Available SWCC tests lack consideration about this effect and therefore the results always have much error. In view of enhancing accuracy of SWCC,by pressure plate apparatus method and filter paper method,this paper measures matrix suctions of laterite at an area in Hunan with different water content. Meanwhile, the rule of volume varying with water content is acquired based on shrinkage tests. Shrinkage coefficient is obtained and volume correction formulation is deduced. Finally,the SWCC is corrected by involving volume change effect. Study results show that volume change of laterite with water content varying has significant influence on SWCC. Under the same matrix suction condition, saturation degree and volume water content of laterite after correction are obviously higher than those before correction, and the difference becomes more obviously with the increase of matrix suction.

关 键 词：红黏土 土水特征曲线 压力板仪法 滤纸法 收缩试验 体积变化修正 

分 类 号：TU411.8[建筑科学—岩土工程]