多元结构抬田饱和-非饱和渗流三维控制数模优化分析

Optimizing Saturated and Unsaturated Seepage of Raising-farmland Based on Multi-component Three-dimensional Finite Element Analysis

以江西省峡江库区土料实测数据为依据,通过实验获得土料基本物理参数,用Van Genuchten(VG)模型拟合土壤水分特征曲线及非饱和导水率,建立由耕作层、犁底层、防渗层和垫高层组成的抬田多元地基结构。采用饱和—非饱和渗流三维有限元分析方法建立数学模型进行计算,通过数值计算结果与实验模型数据对比,证明该数学模型是合理可靠的。在此基础上,建立数学模型模拟计算各土层不同压实度、不同厚度对抬田渗流的影响。通过模拟分析计算,大幅减小了试验工作量,并得出了可供工程使用的结构参数。

The soil water characteristic curve and unsaturated hydraulic conductivity gained from seepage tests in Xiajiang reservior area of Jiangxi Province,were fitted by the Van Genuchten（VG） model,and a new multi-component model consisting of plough layer,plough pan,impermeable layer and raising layer was established for the raising-farmland.A three-dimensional saturated-unsaturated mathematical model was also used to simulate the tests based on the parameters of the VG model.The results show that the mathematical model was reasonable and reliable.In addition,the effects of soil compaction and the thickness on the raising-farmland seepage were investigated.A large number of experiments were reduced by the mathematical analysis and the simulated parameters could be used in the engineering design and construction.