Using the Finite Discrete Element Method (FDEM) to Correlate Simulated Microfractures to Acoustic Emissions in Brittle Anisotropic Rock

The study of rock mechanics is a rapidly evolving field of research due to the increasing demand for underground infrastructure in deeper and more complex rock masses that includes structure such as joints and rock fabric. Among the increased demand is the long-term storage of radioactive waste created from nuclear power generation. There has been extensive research into the behaviour of anisotropic rock as failure commences at the grain scale and propagates into macroscopic fracture, enhanced by technological advances in both laboratory testing and numerical simulation methods. These include the recording of Acoustic Emissions (AE) during laboratory tests which are elastic vibrations emitted when microcracks form and/or propagate, and numerical simulation using the combined Finite-Discrete Element Method (FDEM). This research applies both laboratory and numerical methods to track damage progression in brittle anisotropic rock at the laboratory specimen scale. For laboratory tests, AE are recorded during Unconfined Compressive Strength (UCS) tests on foliated metasedimentary rock from the Bathurst Mining Camp, New Brunswick, Canada, as well as Brazilian Tensile Strength (BTS) tests on three granitic rocks from the Pointe du Bois Pluton, Manitoba, Canada. The same laboratory tests are then recreated as FDEM models, in which finite elements are permitted to separate from each other, thus allowing damage propagation to be tracked in simulation. In this research, a method of comparison between AE and damage propagation in FDEM models is proposed, while addressing the complications of calibrating numerical models that include rock fabric, which is present in the UCS tests performed and simulated. Modifications to the methods of interpreting AE data, specifically with respect to the selection of damage thresholds, and the determination of validity of BTS tests, are also proposed. Lastly, limitations in recording AE discovered after comparison to numerical models are discussed, and recommendations for future work to address these limitations are presented.

Department dc:contributor.department

Geological Sciences and Geological Engineering

Year dc:date.issued

2026

Author dc:creator

• Malicki, Ethan Aleksander

Advisors dc:contributor.supervisor

• Day, Jennifer
• Diederichs, Mark

• Finite Discrete Element Method
• Acoustic Emissions
• Numerical Modelling
• Irazu
• Foliation
• Laboratory Testing

Statement dc:rights

• Attribution-NonCommercial-NoDerivatives 4.0 International

Licence dc:rights.uri

• http://creativecommons.org/licenses/by-nc-nd/4.0/

Language dc:language.iso

eng

Handle dc:identifier.uri

https://hdl.handle.net/1974/36399

OAI identifier oai:identifier

oai:queensu.scholaris.ca:1974/36399