冻融循环作用下路基冻胀性能试验研究  

Experimental Research on Frost Heave Performance of Subgrade under Freeze-thaw Cycle

作　　者：陈亚军 Chen Yajun(Shanxi Provincial Transportation New Technology Development Co.,Ltd.,Taiyuan 030006,China)

机构地区：[1]山西省交通新技术发展有限公司,太原市030006

出　　处：《北方交通》2024年第8期25-28,共4页Northern Communications

摘　　要：为了探究冻融循环作用下路基土的冻胀性能变化规律,以西部某高速公路冻害路段典型断面为依托工程,取现场土样制作路基模型,开展室内冻胀试验,分析冻融循环下路基温度、位移、含水量及含盐量的变化规律。研究认为,不同深度、不同水平距离处的温度变化规律相近,均呈现余弦曲线变化,约滞后环境温度1/4周期;距路基顶部越近,以及距中心线越远处(即越接近冷端)温度波动越明显;在温度到达最低点或最高点后约1/2个周期,冻胀量或融沉量达到最大值;温度对路基水分迁移有较大影响,温度较低时,路基内部水分向上部冷端迁移,导致上部土体含水量增大并冻结;温度较高时,水分几乎不发生迁移。In order to explore the variation law of frost heave performance of subgrade soil under the freeze-thaw cycle,based on the typical section of the freezing-damaged section of an expressway in western China,the subgrade model is made by taking on-site soil samples,and the indoor frost heave test is carried out to analyze the variation law of subgrade temperature,displacement,moisture content and salt content under the freeze-thaw cycle.The research shows that,the variation laws of temperature at different depths and at different horizontal distances are similar,and all of them show a cosine curve change,which can lag the ambient temperature by about 1/4 cycle.The closer to the top of the subgrade and the farther away from the centerline(closer to the cold end),the more pronounced the temperature fluctuations become.About 1/2 cycle after the temperature reaches the lowest or highest point,the amount of frost heave or thawing sedimentation reaches the maximum value.When the temperature is low,the moisture in the subgrade migrates to the upper cold end,resulting in the increase of the moisture content of the upper soil body and freezing.When the temperature is high,there is little migration of moisture.

关 键 词：季节性冻土 冻融循环 路基 冻胀性能 

分 类 号：U416.1[交通运输工程—道路与铁道工程]