季冻区典型土类冻胀特性试验研究

Experimental study on frost heaving characteristics of typical soils in seasonal frozen area

冻胀是季冻区工程常见灾害,为了研究季冻区不同土类的冻胀特性,本文选取3种季冻土—黏土、粉质黏土和分散土,基于单向冻结封闭系统,考虑含水率、干密度和土质3个因素,采用单因素冻胀试验设计方法,给出了3种土类冻胀的特性。结果表明:随含水率的增大,3种土的冻胀率随之增大而后波动较小,粉质黏土的冻胀效应最强,黏土次之,分散土冻胀率最小;随干密度的增大,黏土和粉质黏土的冻胀率先增大后减小,分散土的冻胀率则不断增大;多数情况下,3种土类冻胀率均在冻结温度-10℃左右达到最大值。

Frost heaving is a common disaster in the seasonal frozen area.In order to study the frost heaving characteristics of different soil types in the seasonal frozen area,basing on the closed system and considering three factors which are water content,dry density and the types of soil,using the single factor frost heave test design method,this paper give three types of soil which are clay,silty clay and dispersed soil frost heave characteristics.The results show that with the increase of water content,the frost heave rates of the three types of soil increase and then fluctuated less.The frost heave effect of silty clay is the strongest,the clay is the second,and the frost heave rate ofthe dispersed soil is the smallest.With the increase of dry density,the frost heave rates of clay and silty clay increase first and then decrease,and the frost heave rate of dispersed soil increases continuously.In most cases,the frost heaving rates of the three types of soil reach the maximum at freezing temperature of-10℃.