One-dimensional analytical analysis and parameter study of coupled deformation and seepage in unsaturated soils

By a Fourier integral transform,an analytical solution to 1D coupled seepage and deformation is obtained.The permeability coefficient and pore-water pressure relationship,and the soil-water characteristic curve are represented using exponential functions.Arbitrary initial pore-water pressure distributions and flux boundary conditions are considered in the analytical solution.The analytical analysis demonstrates that the coupling of seepage and deformation plays an important role in rainfall infiltration in unsaturated soils.In the early stage of water infiltration,the difference between the coupled and uncoupled conditions becomes marked over time,and in the late stage,the difference caused by the coupling diminishes towards the steady state.The effect of the parameters on the governing equations is also analyzed.The ratio of rainfall intensity to saturated permeability(q/ks) also has a strong influence on the coupled infiltration and deformation in unsaturated soils.The difference between the uncoupled and coupled conditions is closely linked with the decreasing desaturation coefficient(α).