重塑非饱和粘性土的抗剪强度参数与物理状态变量的关系研究

采用分层击实的方法重塑制备三轴试验土样。按5级围压(100kPa,200kPa,300kPa,450kPa,600kPa)完成了土样的三轴压缩UU试验。试验结果表明:在水分状态和密度状态空间,该重塑非饱和粘性土抗剪强度参数的分布具有明显的规律性,但这种规律性不易用简单函数表达。粘聚力的分布呈倾伏的不规则背斜面,内摩擦角的分布呈变形的W型折曲面。粘聚力和内摩擦角与含水量的关系是强非线性的,与干密度的关系总体上是弱非线性的。存在两个特征含水量18 16和16 34,不同密度状态的土样在特征含水量18 16处粘聚力和内摩擦角均取极大值,在特征含水量16 34处内摩擦角均取极小值。

Relation between Shear Strength Parameters and Physical State Variables of Remolded Unsaturated Cohesive Soil

The triaxial experiment soil specimen remolded by compacting the soil in layers is adopted for this study. The UU triaxial compression tests were conducted acco rding to five classes of surrounding pressure emcompassing 100 kPa, 200 kPa, 300 kPa, 450 kPa and 600 kPa. Distribution of shear strength parameters of remolded unsaturated cohesive soil is regular in moisture state and density state but is not easy to be expressed by simple function. Distribution of cohesion is an irr egular plunging anticline while the distribution of internal friction angle meta morphosed W- type flex surface. Cohesion and internal friction angle has a stro ng nonlinear relation with water content and a weak nonlinear relation in genera l with dry density. There are two characteristic water contents: 18.16 and 16. 34. Cohesion and internal friction angle of soil sample in different density tak es the maximum value at characteristic water content 18.16 and the minimum val ue at characteristic water content 16.34.