补水条件下路基土体冻结过程中的温湿度分布研究

Temperature and Humidity Distribution of Subgrade Soil During Freezing Under Water Replenishment

季节冻土区路基土中的水热迁移往往导致道路病害。为进一步研究季节冻土区路基土体在冻结过程中温度和水分的变化规律,建立开放系统条件下的土体水-热耦合理论模型,然后利用有限元软件进行求解,并借助补水条件下的单向冻结试验对模型的准确性进行验证。结果表明:土体冻结期间,沿试样高度方向的温度分布呈现由非线性分布向线性分布过渡趋势,未冻区水分在温度梯度作用下向冻结区迁移,并在冻结锋面处含水率发生突变;建立的开放系统条件下的土体水-热耦合理论模型能够较好地预测土体冻结过程中的温度和水分变化。

Water and heat transfer in subgrade soil in seasonally frozen soil area will lead to road diseases.In order to further analyze the variation law of temperature and moisture of subgrade soil in seasonally frozen soil area during freez-ing,the soil water heat coupling theoretical model under the condition of open system is established,which is solved by finite element software,and the accuracy of the model is verified by one-way freezing test under water replenishment condition.The results show that the temperature distribution along the height direction of the sample shows a transition trend from nonlinear distribution to linear distribution.The water in the unfrozen area migrates to the frozen area under the action of temperature gradient,and the water content changes suddenly at the freezing front.The soil water heat coupling theoretical model under the condition of open system can predict the changes of temperature and humidity in the process of soil freezing.