Research Overview

We study the mechanics and multiphysics of soils, rocks, and other granular and porous media, and how their behavior governs interactions with natural and engineered systems. These processes span multiple spatial and temporal scales, involving complex material response, large deformation, and coupled mechanical, hydraulic, thermal, and chemical effects, posing fundamental challenges for mechanistic understanding and predictive modeling.

To address these challenges, we combine physics-based theory, advanced computational methods, laboratory experiments, and data-enabled approaches. By linking material-scale mechanisms with system-level behavior, our work advances predictive geomechanics and supports informed engineering decisions in complex environments

Areas of Research

Deformation and Flow of Geomaterials

A hillside can stand for centuries and then collapse in seconds. Soil beneath a foundation creeps imperceptibly until a structure tilts. Snow under a rolling tire compacts, shears, and flows all at once. What these situations share is a material that does not fit neatly into "solid" or "fluid" — its behavior depends on how fast it is loaded, how densely it is packed, how much water it contains, and even its temperature.

We study how and why geomaterials transition between solid-like and fluid-like states, and what controls the large deformations that follow. Our research addresses the mechanics that underlies these transitions: post-failure runout, soil and granular rheology across grain sizes, freezing- and thawing-induced phase changes, and the interaction of deformable ground with structures and machines.

Large deformation and post-failure flow · Granular and soil rheology · Frozen and partially frozen soils · Soil–structure interaction · Terramechanics and ground–machine interaction · Geohazards

Fracture of Rocks and Geomaterials

Rocks fail by fracturing, from microcracks that nucleate silently under compression to earthquake ruptures that propagate for hundreds of kilometers in seconds. Predicting when and how fractures initiate, grow, branch, and coalesce is essential for underground energy systems, resource extraction, seismic hazard assessment, and rock slope stability.

We develop unified computational models for the full spectrum of fracture in geologic materials. Our phase-field models provide a variational, regularized description of crack evolution that accommodates tensile, shear, and mixed-mode failure together with frictional contact, surface roughness, and rate-and-state fault friction.

Fracture and damage mechanics of rocks · Phase-field modeling of fracture · Crack propagation under complex stress states · Strain localization · Fault rupture mechanics

Multiphysics of Porous and Fractured Media

Geomaterials are porous, fluid-saturated, and thermally active. Deformation alters the pore space; flow redistributes pressure; temperature shifts phase boundaries. These processes couple, and in problems from hydraulic fracturing to energy geostructures to underground waste isolation, no single physics suffices.

We build theoretical and computational frameworks for the coupled multiphysics that governs geomaterials in the subsurface and in engineered systems. Our work combines rigorous theoretical formulations with advanced numerical methods to capture the full complexity of these coupled processes.

Poromechanics · Unsaturated soil mechanics · Thermo-hydro-mechanical coupling · Hydraulic fracturing · Fractured porous media · Energy geostructures · Chemo-mechanical processes · Freezing in porous media

Approaches

Theoretical Modeling

We develop physics-based theoretical models grounded in continuum mechanics, thermodynamics, and micromechanics. Our modeling efforts span elastoplasticity, viscoplasticity, critical state soil mechanics, fracture, damage, and rheology, with an emphasis on formulations that are both physically faithful and computationally tractable.

Elastoplasticity and viscoplasticity · Critical state soil mechanics · Anisotropy · Granular and suspension rheology · Fracture and damage mechanics · Homogenization

Computational Methods

We design robust and scalable numerical methods for simulating highly nonlinear, coupled, and multiscale geomechanical phenomena, with a particular focus on large deformations, evolving discontinuities, and strong multiphysical coupling.

Finite element method (FEM) · Material point method (MPM) · Phase-field models · Fully coupled multiphysics solvers · Contact and interface mechanics · High-performance computing

Data-Enabled Approaches

We integrate physical laws, constitutive structure, and observational data through hybrid approaches that improve prediction, parameter inference, and model discovery in geomechanical systems.

Differentiable simulation · Physics-informed machine learning · Inverse analysis · Surrogate modeling · Model discovery

Experimental Characterization

We conduct laboratory testing to measure fundamental material behavior, calibrate and validate constitutive models, and uncover new phenomena that motivate theoretical development.

Triaxial testing · Ring/interface shear testing · Consolidation testing · Dynamic and rate-controlled testing · Temperature-controlled testing · Frozen soil testing

Research Overview

Areas of Research

Deformation and Flow of Geomaterials

Fracture of Rocks and Geomaterials

Multiphysics of Porous and Fractured Media

Approaches

Theoretical Modeling

Computational Methods

Data-Enabled Approaches

Experimental Characterization

Sponsors

Funding Agencies

Research Institutes and Universities

Industry and Others

SNU Geomechanics Lab