Multi-Scale Approach for Modeling Desiccation Shrinkage in Granular Soils

Abstract

This paper aims to identify and quantitatively evaluate various critical mechanisms associated with the processes of desiccation shrinkage and cracking in drying silty soils. A previously developed 1D bundle-of-tubes model is refined to simulate the various stages of drying shrinkage in 2D, using the actual pore size distribution based on Mercury Intrusion Porosimetry (MIP) data. Experimental evidence at a meso-scale has shown that the air entry phenomenon may occur in two possible scenarios: air incursion at the external surface and formation of vapor nucleus in the interior. Further transition of solid-water structural configuration into funicular and pendular states from initially capillary state is simulated.

Effect of Diatomaceous Earth on Desiccation Cracking of Expansive Soils

“…Eventually, at a macroscopic level, the suction value (i.e., the difference between air pressure and water pressure) at the beginning desaturation point is referred to as the air entry value. Negative water pressure is a critical parameter in determining the desiccation property of the expansive soil when the gas phase intrudes the saturated porous soil body [18]. Hence, capillary suction in the upper layer is developed, which affects the arrangement of soil particles leading to a volume change due to the rearrangement of the soil particles.…”