In order to study seepage mechanism of soil

there are some basic assumptions

the soil is saturated

and flow is laminar in the process of seepage. Based on lattice Boltzmann method at the representative elementary volume(REV) scale

the mesoscopic seepage numerical model of soil under pressure is established

considering the effects of macroscopic statistical parameters

i.e. porosity

permeability and effective viscosity coefficient. The D2Q9 model is applied for the discrete velocity direction. In the macroscopic boundary condition

it is impermeable in the left and right sides; and it is controlled by pressure in the upper and lower boundaries

which is decided by setting different density. And the non- equilibrium extrapolation scheme is used in the microscopic boundary. The porous media is set to be fluid in the study region by letting 1.0 and

the corresponding program is compiled to verify the Poiseuille flow. Combined with an example

the influence of porosity

permeability and seepage pressure on the seepage velocity driven by pressure is discussed for soil

and the results of this paper are in good agreement with that calculated by Darcy’s law. Therefore

lattice Boltzmann method at the REV scale could effectively simulate the seepage characteristics of soil

and it provides a new research approach for further study of seepage mechanism.