不同冻结条件下季节冻土粉质粘土冻融特性试验研究

Experimental Study on Freeze-Thaw Characteristics of Powdery Clay in Seasonal Frozen Soil under Different Freezing Conditions

改变土体干密度和补水条件,对粉质粘土进行了冻结融化试验,研究其封闭条件和开放条件下冻胀量、冻胀率、融沉量、融沉系数及水分迁移的变化规律。试验结果表明:封闭系统条件下的融沉量小于开放系统的融沉量,融沉系数与干密度呈负相关,且拟合度较好;开放系统条件下的冻胀量总体明显高于封闭系统的冻胀量,冻胀率随干密度的增加而增大;开放系统的水分迁移量较封闭系统迁移量大,土体含水率随高度的增加而降低,干密度愈大水分迁移量愈小。

To study the variation of frost heave,frost heave rate,thawing settlement,the coefficient of thawing settlement and water migration under closed and open conditions,the freezing and thawing tests of powdery clay were carried out by changing the soil's dry density and water supply condition.The results show that the thawing settlement under the closed system is less than that under the open system,and the coefficient of thawing settlement is negatively correlated with the dry density and the fitting degree is better.The frost heave of the open system is obviously higher than that of the closed system,and the frost heave rate increases with the increase of the dry density.The water migration of the open system is larger than that of the closed system,and the water content of the soil decreases with the increase of the height,and the water migration decreases with the increase of the dry density.