大气作用下红黏土路基的湿热耦合数值分析

Numerical simulation of moisture-heat coupling of laterite soil subgrade under atmospheric effect

针对红黏土路基边坡受大气和车载耦合作用极易发生浅层滑塌等病害问题,以厦成高速湖南郴州段的红黏土路基为背景,利用湿热耦合数学模型,结合郴州地区实测的气象数据,采用多场耦合软件模拟了环境因素作用下路基的温度场、水分场的演化规律。计算结果表明:大气温度的年平均影响深度约为3 m,日影响深度约为0.5 m;路基边坡水分部分受降雨和蒸发影响,路基底部水分受地下水毛细上升控制,路基内部水分受温度和湿度的耦合影响。

With regard to the shallow landslide of slope of laterite soil subgrade easily induced by the coupling effect of climate and vehicle,the evolution rules of temperature and moisture fields of the subgrade of Chenzhou section in Hunan Province of Xiamen-Chengdu Expressway under environmental factors are stimulated based on the observed atmospheric data in Chenzhou area by means of the Philip de Vries moisture-heat coupling model and multi-field coupling software.The calculated results indicate that the annual mean depth influenced by the temperature is about 3m and the daily mean one is about 0.5m.The moisture of subgrade slope is partially influenced by rainfall and evaporation,and that of roadbed bottom is controlled by the capillary rise of groundwater.The internal moisture of the subgrade is influenced by the coupling effect of temperature and humidity.