非饱和土渗透函数方程的间接确定

Indirect determination of permeability function equation of unsaturated soils

利用应力应变控制式非饱和土三轴仪,测定了非饱和土的基质吸力和体积含水量,由此得出粉质粘土一系列的土-水特征曲线,并由非线性曲线拟合得出土-水特征曲线方程,根据其与渗透函数的关系,推导出Mualem渗透函数方程的具体形式,由其计算得出的非饱和土的渗透系数和直接测量法得到的渗透系数较为一致,从而进一步证明了Mualem方程的具体形式的合理性。

The triaxial test instrument for unsaturated soils controlled by stress and strain was used to measure the matric suction and volumetric water content of unsaturated soils; and a set of soil-water characteristic curves of silty clay were obtained. The equation of soil-water characteristic curve was also gained by use of nonlinear curve fitting. The concrete form of the Mualem equation was deduced based on the relation between the soil-water characteristic curve equation and the permeability function equation. The results calculated by the concrete form of the Mualem equation are consistent with those measured by the direct method. The concrete form of the Mualem equation was further proved to be reasonable.