01661497

Component

The accurate prediction of the moisture content in soil is important for pavement engineering. The MEPDG uses the Enhanced Integrated Climate Model (EICM) to consider the effects of environment on the moisture contents of unbound and subgrade soil using models related to unsaturated hydraulic conductivity. These models are mostly empirical and not applicable to relatively dry conditions. This is because at relatively dry condition, the moisture in the pore structure of the soil is not inter-connected. Therefore, the moisture diffusion in porous material controls the moisture migration. When diffusion coefficient is a nonlinear function of pore relative humidity (RH), there is no close-form solution of the constitutive differential equation of the moisture diffusion. Finite-volume method (FVM) is similar to finite-element method (FEM) by using very small and finite-sized elements for simulation, but based on the conservation of physical laws. Therefore, FVM will be more suitable for flux conservation problems as moisture diffusion. This study used FVM for the numerical simulation of the moisture diffusion in soils. The FVM results was verified with laboratory experiments and compared with FEM results. The results indicate the applicability of using FVM in the simulation of the moisture migration in soils.

This paper was sponsored by TRB committee AFP60 Standing Committee on Engineering Behavior of Unsaturated Geomaterials.

18-03332

English

12p

2018

Transportation Research Board 97th Annual Meeting

Digital/other

Figures; References; Tables

Drying; Numerical analysis; Porous materials; Soil water; Subgrade (Pavements)

Geotechnology; Highways; Materials; Pavements

Transportation Research Board Annual Meeting 2018 Paper #18-03332

TRIS, TRB, ATRI

Jan 8 2018 10:49AM