大气作用下浅层非饱和黄土温度变化及其影响因素研究  

EXPERIMENTAL TESTS ON TEMPERATURE CHANGE OF SHALLOW UNSATURATED LOESS UNDER ATMOSPHERIC ACTION AND ITS INFLUENCING FACTORS

作　　者：李仁杰 王旭[1,2] 张延杰 蒋代军[1] 李建东[1] 王瑞浦 LI Renjie;WANG Xu;ZHANG Yanjie;JIANG Daijun;LI Jiandong;WANG Ruipu(School of Civil Engineering,Lanzhou Jiaotong University,Lanzhou 730070;National and Provincial Joint Engineering Laboratory of Road&Bridge Disaster Prevention and Control,Lanzhou 730070;Luoyang Planening and Architectural Design Research Institute Co.,Ltd.,Luoyang 471000)

机构地区：[1]兰州交通大学土木工程学院,兰州730070 [2]道桥工程灾害防治技术国家地方联合工程实验室,兰州730070 [3]洛阳规划建筑设计研究院有限公司,洛阳471000

出　　处：《工程地质学报》2019年第4期766-774,共9页Journal of Engineering Geology

基　　金：国家自然科学基金(51868038,41662017,41562014)资助~~

摘　　要：为了研究大气作用下西北地区浅层非饱和黄土温度场的变化规律及其影响因素。填筑一维土柱模型,在室外自然条件中做大气循环作用下的蒸发模型试验。试验结果表明:在0~10cm深度范围内,土体温度随深度的增加而降低,在土样表层5~10cm处温度最低;在相同的外界条件下,土体初始体积含水率越高、压实度越大,导热系数越大,温度变化幅度越大。随着深度增加和蒸发时间增长,压实度和含水率引起的导热差异叠加,使得同一深度处不同压实度和不同含水率土体的温差增大;土体初始体积含水率和压实度均对温度的迁移产生影响,相对于随压实度的变化,土体体积含水率的改变对土体温度迁移影响更显著;随着蒸发时间的增加,温度由表及里逐渐升高,在深度方向上温度先减小后增大。不同深度处土体温度增长曲线大致为“S”型递增曲线,可分为蒸发3阶段。This paper aims to research the variation law of temperature field and its influencing factors of shallow unsaturated loess in the northwestern of China.A one-dimensional soil column model is built and placed under outdoor natural conditions.It is used to test the outdoor evaporation model under atmospheric temperature cycle.The experimental results show that the soil temperature decreases with the increase of depth in the depth range of 0~10 cm,and the temperature is the lowest at 5~10cm in the surface layer of the soil sample.Under the same external conditions,the initial volume content of the soil is higher and the degree of compaction is higher.The larger the thermal conductivity and the greater the temperature change.As the depth increases and the evaporation time increases,the difference in thermal conductivity caused by compaction and water content is superimposed.So the temperature difference between soils with different compaction degrees and different water contents at the same depth increases.Both of the initial volume content of the soil and the compaction degree of soil have an effect on the temperature migration.Compared with the change of compaction degree,the change of soil volume content has a more significant effect on soil temperature migration.With the increase of evaporation time,the temperature gradually increases from the surface to the inside.The temperature in the depth direction decreases firstly and then increases.The soil temperature growth curve at different depths is roughly a“S”type increasing curve,which can be divided into three stages of evaporation.

关 键 词：非饱和黄土 温度运移 初始体积含水率 压实度 模型试验 

分 类 号：TU473[建筑科学—结构工程]