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Title: Coupled Analysis of Desiccation Cracking in Unsaturated Soils through a Non-Local Mathematical Formulation
The formation of desiccation cracks in unsaturated soils as a discontinuity phenomenon can compromise the integrity of civil infrastructure on unsaturated soils. Because of the singularity at such discontinuities, the mathematical modeling of desiccation cracking is challenging. In this study, we apply a coupled nonlocal peridynamic poroelastic framework to model desiccation cracking in unsaturated soils. The soil skeleton is modeled by a nonlocal peridynamic elastic solid. A peridynamic equivalence of the generalized Darcy’s law is utilized to model unsaturated fluid flow. Cracking is determined by a critical stretch criterion between material points as well as an energy criterion. We present numerical simulations of desiccation cracking in soil bars and thin soil discs for one-dimensional cracking and two-dimensional cracking networks, respectively. The numerical results have demonstrated that the proposed nonlocal mathematical framework is a promising and robust method for modeling desiccation cracking in unsaturated soils.  more » « less
Award ID(s):
1659932
PAR ID:
10145847
Author(s) / Creator(s):
;
Date Published:
Journal Name:
Geosciences
Volume:
9
Issue:
10
ISSN:
2076-3263
Page Range / eLocation ID:
428
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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