Multi‐phase‐field microporomechanics model for simulating ice‐lens growth in frozen soil

Abstract

This article presents a multi-phase-field poromechanics model that simulates the growth and thaw of ice lenses and the resultant frozen heave and thaw settlement in multi-constituent frozen soils. The growth of segregated ice inside the freezing-induced fracture is implicitly represented by the evolution of twophase fields that indicate the locations of segregated ice and the damaged zone, respectively. The evolution of two-phase fields is induced by their own driving forces that capture the physical mechanisms of ice and crack growths, respectively, while the phase-field governing equations are coupled with the balance laws such that the coupling among heat transfer, solid deformation, fluid diffusion, crack growth, and phase transition can be replicated numerically. Unlike phenomenological approaches that indirectly capture the freezing influence on the shear strength, the multiphase-field model introduces an immersed approach where both the homogeneous freezing and the ice-lens growth are distinctively captured by the freezing characteristic function and the driving force accordingly.Verification and validation examples are provided to demonstrate the capacities of the proposed models.

A coupled phase‐field method (PFM) and thermo‐hydro‐mechanics (THM) based framework for analyzing saturated ice‐rich porous materials

“…To ensure consistency in the strain measurement used to describe the deformation, a key assumption is that the relative velocity of the ice constituent is negligible compared to that of other constituents, such as the solid constituent. This assumption is supported by previous studies, such as those in Zhou and Meschke 91 , Suh and Sun 92 ,Na and Sun 50 , which suggests that the ice velocity can be considered as negligible compared to the solid velocity. This approach allows the strain measure $$\bm{\epsilon }_S$$ to be used to describe the deformation of both ice and solid constituents together.…”

On Diffusion and Transport Acting on Parameterized Moving Closed Curves in Space

“…Thin liquid pathways occur between grains and ice during soil freezing and mediate mass transport responsible for mechanical effects such as the frost heave (see e.g. [38,42,45]). Following the above motivating applications, we consider the following transport problem along a moving curve Γ:…”

Numerical simulation of frost heave of saturated soil considering thermo‐hydro‐mechanical coupling

“…However, in their model the water can freely flow towards the segregated zones, the effect of the stress of ice lens on water flow is neglected, which might not in accordance with the actual physics when the overburden load reaches a high value. There are also phase field models proposed in the literature [23][24][25] to capture the crack growth induced by ice segregation, which can address numerical stability issues involved in fracture development by introducing phase field variables. These works presented are capable of simulating the frozen heave and thaw settlement involved ice lens under constant overburden load, but they might not consider the effects of the increasing frost heave pressure on phase change and THM coupling processes in the freezing soils under restrained conditions, which should be further explored.…”