摘要
分散性黏土冻融循环导致的破坏非常普遍,在我国东北地区水利工程中尤为严重。开放系统中分散性黏土冻融特性有别于非分散性黏土,土体导热系数是土体热分析最重要的参数之一。本文以分散性黏土为研究对象,阐明了影响分散性黏土导热系数的因素;基于Johansen法的改进,建立了适合分散性黏土特点的导热系数预测方法。研究表明,分散性黏土导热系数的影响因素主要为矿物成分、含水率、孔隙率(干密度)和温度。土体温度为负温时,温度越低,土的导热系数越大。初始含水率低于10%,土的导热系数不受温度的影响;初始含水率大于15%,土的导热系数受温度影响较大。饱和状态下的分散性黏土导热系数有别于非分散性黏土,采用串联并联预测模型方法来计算。所提出的分散性黏土导热系数预测方法和公式,可反映土体温度、土体矿物成分、含水率、干密度的影响,与试验结果吻合,并可为分散性黏土研究和工程应用提供参考和指导。
It is very common that the dispersive clay damage is caused by the freeze-thaw(F-T)cycles,especially in water conservancy projects in Northeast China.The F-T characteristics under hydrating conditions of dispersive clay are different from those of non-dispersive clay.The thermal conductivity of soil is the most important parameter in soil thermal analysis.In this paper,the dispersive clay is taken as the research object to clarify the factors affecting the thermal conductivity of the dispersive clay.Based on the improvement of the Johansen method,a thermal conductivity prediction method suitable for the characteristics of dispersive clay was established.The results show that the main factors affecting the thermal conductivity of dispersive clay are mineral composition,moisture content,porosity(dry density),and temperature.When the test samples are below zero,the lower the temperature,the greater the thermal conductivity of the soil.When the initial moisture content is lower than 10%,the thermal conductivity of soil is not affected by temperature,but for 15%,the thermal conductivity of soil is greatly affected by temperature.The thermal conductivity model of dispersive clay in the saturated state is different from that of non-dispersive clay,and it is calculated by series parallel prediction models.The proposed prediction model and formula for the thermal conductivity of dispersive clay in the seasonal frozen area could reflect the influence of temperature,mineral composition,moisture content,and dry density.It is consistent with the test results and could be used for academic research and engineering applications of dispersive clay in the seasonal frozen area.
作者
王理想
宋新江
黄铭
王淼
WANG Lixiang;SONG Xinjiang;HUANG Ming;WANG Miao(College of Civil Engineering,Hefei University of Technology,Hefei 230000,China;Anhui and Huaihe River Institute of Hydraulic Research,Hefei 230000,China;Heilongjiang Province Hydraulic Research Institute,Harbin 150080,China)
出处
《水利学报》
EI
CSCD
北大核心
2023年第3期311-322,共12页
Journal of Hydraulic Engineering
基金
安徽省自然科学基金“水科学”联合基金项目(2208085US01)
中国博士后基金面上项目(2021M690946)
黑龙江省自然科学基金项目(LH2021E111)。
关键词
分散性黏土
导热系数
冻土
影响因素
预测方法
dispersive clay
thermal conductivity
frozen soil
influence factors
prediction method
