On the Consequences of Microstructural Evolution on Macroscopic Behavior for Unsaturated Soils

Abstract

Volumetric behavior of soils is amongst the most important parameters to be taken into consideration to describe many aspects regarding the hydro-mechanical coupling of unsaturated soils, such as the behavior of CO2 reservoirs subjected to moisture gradients, or the initiation of cracks due to suction loading-reloading. Experimental observations show a clear transition of compressibilities as soils reach unsaturated states when tested under suction increments. This is termed shrinking limit. We address this behavior taking into consideration the evolution of pores where a mechanism of pore deformation is proposed to predict this shrinking limit. This model requires no other parameter than the initial pore-size distribution of the material.