Abstract
A numerical model is proposed to simulate the seepage through unsaturated soil based on some mechanical and probabilistic considerations on the particle scale. In the model the probability density functions are introduced to estimate the state of voids in soil. The hydraulic properties of unsaturated soil ; i. e. the relations among the water content, pF-value and permeability coefficient are theoretically derived by using the model, and numerically calculated by using a personal computer. The numerical result is compared with a pF-test and unsaturated permeability test on Toyoura sand. In the proposed model the hydraulic properties of unsaturated soil can be derived by only the grain size distribution.
