Predicting the Yield Stress of Geomaterials from Their Microstructure

The seminal work of Gurson (J Eng Mater Technol 99:2–5, 1977) on a simplified pore structure, a single spherical pore, first provided a theoretical relationship between the yield stress and the porosity. This contribution extends the approach to determine the macroscopic yield of a porous material by taking explicitly into account its...

Influence of cementation on the yield surface of rocks numerically determined from digital microstructures

Digital Rock Physics has reached a level of maturity on the characterisation of primary properties that depend on the microstructure - such as porosity, permeability or elastic moduli - by numerically solving field equations on μCT scan images of rock. After small deformations or at depth though, most rocks eventually reach their limit of...

Reconciling asymmetry observations in the permeability tensor of digital rocks with symmetry expectations

Modelling anisotropic flow in rocks requires their full permeability tensor. While theories derived from the upscaling of Stokes flow to Darcy's law may justify the tensor symmetry, homogenisations from micro-scale rock samples often return a non-zero level of asymmetry. Since most studies dismiss these controversial observations as numerical...

Revisiting MODFLOW's Capability to Model Flow Through Sedimentary Structures

Sedimentary structures have unique geometries and anisotropic hydraulic conductivity, both of which control groundwater flow. Traditional finite-difference simulators (e.g., MODFLOW) have not been able to correctly represent irregular, dipping and anisotropic structures due their use of a simplified conductivity tensor, causing many modelers...

μCT scans permeability computation with an unfitted boundary method to improve coarsening accuracy

Flow simulations on porous media, reconstructed from Micro-Computerised Tomography (μCT) scans, is becoming a common tool to compute the permeability of rocks. Still, some conditions need to be met to obtain accurate results. Only if the sample size is equal or larger than the Representative Elementary Volume will the computed effective...