P4b-3. Non-Linear Relationships between Hydrological Properties and Strain

Project leader: Mohammad Saadatfar (Applied Maths, RSPhys ANU)
Industry partner: David Beck, Beck Engineering
  1. Stressed rocks in mines can be damaged by boundary stresses or hydraulic fracturing. We aim to the coupled relationship of fluid and rock in this context.
  2. To provide hydrological parameters into non-linear hydro-mechanical model to allow higher resolution analysis of the impacts of water on the mine.
  3. To estimate permeability change and hydro-mechanical process and coupling between flow and strain.
Alignment within M3D Innovation:
  1. Dynamic experiments and modelling for Materials characterisation.
  2. Overlap with Energy and Resources industry projects.
  1. Ex-situ and in-situ tests will be carried out to parametrise core strength from various depths, chemistry (mineralogy) and heterogeneity.
  2. XCT scans will be utilised to quantify hard rock (>70MPa) textures of prior to testing, midway through the triaxial test and after failure.
  3. Various stress paths will be implemented to determine fracture nucleation.
  4. In-situ experiments using triaxial apparatus will be carried out to find correlation between rock mechanics and pore pressure.
  5. The hydromechanical relationships from the triaxial and permeability testing will be used to validate FE modelling.
Key Milestones:
  1. Selection of specimens relevant to mine and modelling project, commence X-CT scanning and analysis. [Complete]
  2. Perform triaxial permeability test on low strength 12mm. [Complete]
  3. Perform ex-situ mechanical tests on hard rocks (June-2021). [Underway]
  4. Perform triaxial permeability test work on larger cores (25mm) (June-2022).
  5. Results from analysis integrated into coupled hydrological simulation (2022-2023).