Using a 3D Hydro-Mechanical Model to Study the Cyclic Behavior of Unsaturated Soils


Recently, a consistent three-dimensional elasto-plastic model was proposed to study unsaturated soil behavior with consideration of coupled hydro-mechanical hysteresis (hereafter referred to as C3DHM). This model uses a unique yield curve to represent both mechanical and hydraulic yielding (i.e., the occurrence of plastic water content changes and mechanical strains). Moreover, it provides consistent predictions for different soil phases that is considered a significant limitation in many existing models. In this paper, the C3DHM model is used to simulate the behavior of unsaturated soils subjected to cyclic shear loading. Experimental results for suction-controlled (i.e., drained) triaxial tests for soils subjected to cyclic shearing were collected from the literature. The model capabilities were investigated by comparing its predictions against the measured results. The model showed reasonable predictions for both volumetric and shear behaviors. Results showed that the model neglects the shakedown phenomenon that is obvious from experimental results. This phenomenon is critical for many transportation applications. Accordingly, possible modifications for the C3DHM are proposed to better capture the soils' shakedown.

Meeting Name

Geo-Congress 2022 (2022: Mar. 20-23, Charlotte, NC)


Civil, Architectural and Environmental Engineering


National Science Foundation, Grant EMR/2016/001152

Keywords and Phrases

Constitutive Modeling; Cyclic Loading; Elasto-Plastic; Hydro-Mechanical; Shakedown Phenomenon; Shear Strength; Unsaturated Soils

International Standard Serial Number (ISSN)


Document Type

Article - Conference proceedings

Document Version


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© 2022 American Society of Civil Engineers (ASCE), All rights reserved.

Publication Date

23 Mar 2022