Abstract: A typical soil material has an extremely complex internal pore structure and is a typical porous medium. The coefficient of permeability, as one of the important physical properties of geotechnical materials, was evaluated with various potential influencing factors, but the effect of inhomogeneity on the coefficient of permeability is relatively rare evaluated. In order to explore the effect of this non-homogeneity on the permeability characteristics of the porous media, this paper establishes different two-dimensional porous media seepage models that considering the compaction effect through a numerical simulation software. The numerical study results are combined with the actual test results, and therefore, investigates the influence of different distribution patterns of soil particles on the permeability values. The results show that the non-uniform distribution of the soil particles has an obvious influence on the seepage characteristics. When the concentrated distribution of soil particles impedes fluid flow, the permeability decreases significantly. Further, when the non-homogeneity does not actually change the seepage channel size, the effect is smaller.

Key words: highway subgrade, coefficient of permeability, numerical analysis, porous media, non-homogeneous distribution, two-dimensional numerical simulation