人工填筑路基土体水分运动参数的试验

Experiments on motion parameters of soil moisture in artificial filling subgrade

以低液限粘土和粉土为研究对象,采用滤纸法确定其土体水分特征曲线,应用Van Genuchten模型对土体水分特征曲线进行拟合;利用水分迁移测试系统测试土体含水体积分数时变曲线;基于达西定律,结合土体水分特征曲线和土体含水体积分数时变曲线,提出确定导水率及扩散率的方法。研究结果表明:应用滤纸法和水分迁移测试系统确定土体导水率及扩散率简单、方便;Van Genuchten模型拟合土体水分特征曲线效果能达到工程应用要求。

The experiments are carried out on the low liquid-limit clay and the silt.The characteristics curve of the soil moisture are defined by the filter paper method and fitted based on the Van Genuchten model.The time-variety curve of the volume fraction of the soil water-content is tested by the moisture transmit test instruments.Based on the Dercy law,the method for defining the hydraulic conductivity and the diffusivity of the soil is put forward combining the characteristics curve and the time-variety curve of the volume fraction of the soil water-content.The results show that the applied filter paper method and the moisture measurement system for defining the hydraulic conductivity and the diffusivity of the soil are convenient and feasible.The fitted characteristics curve of the moisture movement by the Van Genuchten model can meet the requirement of the engineering application.3 tabs,6 figs,12 refs.