Multi-phase-field microporomechanics model for simulating ice lens growth and thaw in frozen soil

TL;DR

This paper introduces a multi-phase-field poromechanics model that simulates ice lens growth and thaw processes in frozen soils, capturing complex interactions among heat transfer, deformation, and phase changes.

Contribution

The model uniquely integrates phase-field methods with poromechanics to explicitly simulate ice lens formation and thaw in frozen soils, advancing beyond phenomenological approaches.

Findings

Successfully simulates ice lens growth and thaw in soils

Captures interactions among heat transfer, deformation, and phase change

Validated through verification and validation examples

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. In this model, the growth of segregated ice inside the freezing-induced fracture is implicitly represented by the evolution of two phase fields that indicate the locations of segregated ice and the damaged zone, respectively. The evolution of two phase fields are driven by the 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 observed numerically. Unlike phenomenological approaches that indirectly captures the freezing influence on the shear strength, the multi-phase-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.