Theoretical and Applied Fracture Mechanics - Pathirage Research Group 

We gratefully acknowledge our external funding sources from

• Oak Ridge Associated Universities Ralph E. Powe Junior Faculty Enhancement Award (ORAU)

• National Science Foundation (NSF)

• National Aeronautics and Space Administration (NASA)

• New Mexico Space Grant Consortium (NMSGC)

• New Mexico Department of Finance and Administration (NMDFA)

• New Mexico Department of Transportation (NMDOT)

and internal funding sources from

• UNM Research Allocations Committee (RAC)

and generous gifts from

• New Mexico Society of Professional Engineers (NMSPE)

• Doug Campbell through UNM Foundation

• Donation to the CCEE Department for Research in Finite Element Methods 

Analytical and Computational Methods in Fracture Mechanics

Mathematical Theory and Solution to the Cohesive Crack Model

New procedures are developed to derive closed-form solutions to a certain class of non-trivial cohesive crack problems. See the 2025 Journal of the Mechanics and Physics of Solids paper in publication page.

Cohesive and Inelastic Strain-Based Damage Model and Implementation

We are studying the fundamentals of isotropic damage modeling in the context of finite element method, and we are working on a fast and open-source implementation of such models.

Discrete Method with Damage and Friction Models and Implementation

We are developing a novel discrete model based on tensile fracturing and frictional shear behavior and its open-source implementation for the prediction of fracture in heterogeneous materials.

Regression Statistics in Fracture and Size-effect Tests

The inverse problem of size-effect in quasi-brittle materials was revisited using regression statistics methods. See the 2025 Materials and Structures paper in publication page.

Fracture Mechanics in Nuclear and Extreme Environments

Radiation Effects on Cement Microstructure

We are developing a numerical model to understand the multi-physics behavior of irradiated cement paste. Our aim is to understand the long-term behavior of cementitious materials used in nuclear engineering applications. 

Nuclear Containment Structures Subjected to Blast Loading

We are investigating the effects of extreme dynamic events - high explosive detonation - on containment structures in nuclear power plants. The aim is to assess potential structural damage in a typical prestressed and reinforced concrete containment structure caused by a blast load. 

Injury and Biomechanical Fracture Mechanics

Modeling of Traumatic Brain Injury due to Head Impact

We are simulating low-velocity head impacts to the ground to quantify deformation and stresses in different parts of the brain through a high-fidelity skull and brain model. The aim is to better assess Traumatic Brain Injury (TBI) and improve existing TBI metrics.

Bone Modeling based on Cosserat Continuum Theory

We are revisiting the basics of Cosserat continuum theory for the modeling of bone mechanical behavior. We are also working on the open-source implementation of this model using the finite element method.

Fracture Mechanics in Novel Cementitious Composites

Formulation of a Synthetic S-Type Asteroid Rock

We are formulating and characterizing a synthetic rock to reproduce the mechanical behavior of stony-type asteroids through experiments and numerical modeling, which would eventually provide a better understanding of the fracture properties of these celestial bodies. 

Harvested Fly Ash in Concrete and Modeling

We are formulating a novel concrete mix design incorporating New Mexico harvested fly ash to study its mechanical performance. This project involves a variety of material characterization tests, and thermodynamic modeling of hydration.