Hydromechanical Behaviors of Unsaturated Soils

In this paper, the hydromechanical behavior of unsaturated soils is explored. A constitutive model is proposed to describe the coupled hydraulic and mechanical behavior of unsaturated soils. The compression stiffness parameters, such as (s), (s), s, and s, are analyzed, taking into account the influences of suction, degree of saturation, and net mean stress. Based on the volume change behavior under constant suction and the water retention properties, the relationship between the degree of saturation and volume change has been investigated under both net mean stress and suction. The proposed model is capable of describing the mechanical behavior of unsaturated soils for either isotropic compression or triaxial compression. Indeed, the simulation results of three cases of suction-controlled laboratory tests show good agreement with experimental data.