InterPore2022

A macro-scale elasto-thermo-viscoplastic constitutive model for ‎saturated frozen soils

Jun 1, 2022, 2:35 PM

15m

Oral Presentation (MS12) Advances in modeling and simulation of poromechanics MS12

Speaker

Mr Dana Amini (Research Assistant, Department of Civil Engineering, University of Manitoba, Winnipeg, Manitoba, Canada)

Description

Slow-rate time-dependent behavior (i.e., creep) of frozen soils is experimentally ‎observed in the literature. From ‎a ‎poromechanical point of view, frozen soil is a medium composed of a ‎deformable solid skeleton and a porous ‎‎space filled with unfrozen water and ice. In addition to pore ice, ice-rich permafrost can also contain thin ice lenses. ‎‎The rheological properties of saturated frozen soils due to the ‎coexistence of ice and viscous unfrozen water ‎cause ‎slow rate deformation and loss of shear strength ‎of the soil. Temperature, applied stress conditions, ice ‎content, ‎soil type, and density are key factors ‎controlling the viscoplastic reorganization of the inter-particle ‎microstructure ‎and, subsequently, the ‎creep rate of frozen soils. In this study, an Elasto-Thermo-ViscoPlastic ‎‎(ETVP) constitutive ‎model for frozen soils is formulated within the framework of two-stress state variables in which ‎the ‎cryogenic ‎suction and the net solid phase stress are defined as state variables. In the proposed model, ‎the ‎impacts of the ‎aforementioned factors and their interdependencies, as well as the current state of ‎the frozen soil ‎structure on the ‎creep deformation of frozen soils, are properly considered based on a ‎phenomenological (macro-‎analytical) point ‎of view.‎

Presentation materials

A macro-scale elasto-thermo-viscoplastic constitutive model for ‎saturated frozen soils - Amini et al.pdf