季冻区粉质黏土冻胀特性分析

Analysis of Frost Heaving Characteristics of Silty Clay in Seasonal Frozen Region

粉质黏土属冻胀敏感性土,为了研究其冻胀率随含水率、压实度和冻结温度3个因素的变化规律,对取自黑龙江省境内哈大二级公路的粉质黏土进行了闭式冻胀模拟试验。分析结果表明:闭式冻胀单因素条件下,粉质黏土冻胀率与3个因素分别呈现一定的相关关系,低冻结温度、高含水率以及高压实度会加剧土体冻胀;含水率对冻胀率的影响最大,压实度次之,冻结温度最小;粉质黏土的起始冻胀含水率ω0=0.89ωp,临界冻胀含水率ωc=0.97ωp。此外,在冻胀试验结果的基础上,还应用SPSS统计软件建立了冻胀率为因变量,含水率、压实度和冻结温度为自变量的多元回归模型,模型可以用于粉质黏土的冻胀率预测。

Silty clay is frost heaving sensitive soil. In order to study the regularity of frost heave rate varies with moisture content, degree of compaction and freezing temperature, the closed frost heave simulation test of silty clay from Harbin-Daqing second-class road in Heilongjiang Province is conducted. The analysis result shows that （ 1 ） Under single factor of closed frost heaving, the silty clay frost heave rate has relevant relations with the abovementioned 3 factors. Low freezing temperature, high moisture content and high degree of compaction can increase soil frost heave. （2） The influence of moisture content on frost heave rate is maximum, degree of compaction is the second, and freezing temperature is minimum. （3） The initial moisture content of frost heave of silty clay is ω0=0.89ωp, the critical moisture content of frost heave is ωc=0.97ωp. In addition, based on the test results, the multiple regression analysis models, whose dependent variable is frost heave rate and independent variable are the 3 factors, are established by SPSS statistical software, which can be used in the prediction of frost heave rate of silty clay.