击实膨胀土工程变形特征的试验研究

Test study on engineering deformation characteristics of compacted expansive soil

以湖南邵阳膨胀土为例,对3种击实膨胀土工程变形特性进行了试验研究。试验结果表明:膨胀土的起始含水率和起始干密度对其膨胀力和膨胀量大小的影响是主要的外部因素;根据膨胀力试验和膨胀量试验的试验数据,拟合出膨胀力曲线和膨胀量曲线的变化规律均为指数关系。同时,还研究了膨胀速度曲线、收缩特性曲线的特征及膨胀和收缩两个过程的相似关系。研究结果为膨胀土路堤的设计及膨胀土地基处理等膨胀土问题提供了重要的依据。

By a lot of laboratory tests of expansive soil, in the case of expansive soil in Shaoyang city of Hunan province, the engineering deformation characteristics of three kinds of expansive soils have been test studied. The test results indicate: the beginning water content and dried density of expansive soil are the main outside factors that influence the magnitude of their expansibility and swelling quantity; according to the data of expansibility tests and swelling quantity tests, the variational rule of both expansibility fitted curve and swelling quantity fitted curve is the same exponential relation. At the same time, the characteristic curve and the similar relation between the curve of swelling velocity and the curve of shrinkage tests have been studied. Therefore, the study results have provided the important basis for the design of embankment and treatment technique to the existing expansive soil foundation.