Modeling rainfall infiltration through coarse and fine-grained unsaturated geomaterials

In this paper we study an imbibition test problem defined over a real two-dimensional soil domain subject to in-situ stresses and oedometric boundary conditions. Two different kinds of materials are tested, which are characterized by different pore-structures and hydro-mechanical properties. The aim is that of clarifying the behavior of real materials under real loading conditionss. The stress paths associated to rainfall infiltration processes are simulated by using the commercial code ABAQUS, endowed with an own-made sub-routine developed in order to incorporate the effects of partial saturation into the tangent stiffness.