ABSTRACT
Despite the broad applicability of unsaturated soil mechanics in road engineering, this chapter focuses on heat and water transport mechanisms. The theory of unsaturated soil mechanics allows one to calculate the evolution of some state variables, such as the pore water pressure and the temperature of the materials within the structure of a road. Focusing on the phenomena of mass and heat transport, the main functions and variables regarding water transport are the water retention curve and hydraulic conductivity, while heat capacity and thermal conductivity are the variables required for heat transport. The chapter summarizes the equations that allow the calculation of water flow in unsaturated soils that do not undergo volumetric changes. The fundamental thermal properties for evaluating the heat transport in unsaturated soils are the thermal conductivity and the heat capacity. Three types of boundary conditions are useful for analyzing the problem of water flow in unsaturated materials.
