击实膨胀粘土变形曲线特征的研究

Research on Characteristics of Deformation Curve of Compacted Swelling Clay

以湖南潭邵高速公路 K174～ K186地段所取的 4种膨胀粘土样为例 ,通过大量室内膨胀试验 ,对比研究了膨胀速度曲线、收缩速度曲线的特征。研究结果表明 ,尽管膨胀粘土的膨胀、收缩过程有很多相似特征 ,但两者并非是完全可逆的过程 ,其吸水膨胀速度远比失水收缩速度快。同时 ,利用非线性最小平方拟合法对胀缩曲线进行拟合 ,并给出胀缩曲线的曲线回归方程及其各参数的物理意义。研究结果为膨胀粘土堤坝边坡设计以及膨胀粘土地基加固。

Giving examples of four kinds of soil samples of swelling clay colleted from the section ofK174~K186 of Tan Shao Expressway, the characteristics of curves of swelling speed and contraction speed are studied by means of a large number of indoor swelling tests. The research results show that although the swelling and contraction process of swelling clay are of much similar characteristics, both processes can not be inversed, and the water absorption swelling speed is quicker than the water loss contraction speed. Meanwhile, the non linear minimum square fitting method to fit the swelling contraction curve is adopted, and the regression equation of the swelling contraction curve and the physical meaning of each parameters are given. The research results provides important basis for the design of side slope of swelling clay embankment dam and the consolidation and treatment of swelling clay foundation.