Preprints
Filtering by Subject: Materials Science and Engineering
Stress-strain hysteresis during hydrostatic loading of porous rocks
Published: 2024-01-12
Subjects: Earth Sciences, Materials Science and Engineering
A micro-mechanical model is proposed to predict the stress-strain hysteresis during the cyclic hydrostatic loading of fluid-saturated rocks under drained or undrained conditions. A spherical pore is surrounded by a cracked shell where local deviatoric stress develops despite the remote hydrostatic loading. The effective properties of the material composing the shell are constructed with the crack [...]
Comment on “If not brittle: Ductile, Plastic, or Viscous? By Kelin Wang”
Published: 2022-04-07
Subjects: Earth Sciences, Materials Science and Engineering
In continuum mechanics, viscous materials are those that lack rigidity and elastic response under shear stress. We argue that using the term viscous to refer to the aseismic lithosphere is thus a misnomer, as it denies the propagation of S-waves through the lithosphere in total contradiction to decades of seismic surveys. Likewise, viscous materials lack yield stress, which is another feature [...]
CCC - integrated multiscale study of salt cavern abandonment in the Netherlands
Published: 2022-03-24
Subjects: Geology, Geophysics and Seismology, Materials Science and Engineering, Mineral Physics, Mining Engineering, Other Earth Sciences, Tectonics and Structure
The KEM-17 project of the Dutch State Supervision of Mines presented a critical review of concepts of cavern abandonment and related science. It recommended that analyses of cavern abandonment are done as an integrated project, addressing (i) micro-scale physical processes, (ii) cavern scale models based on field scale experiments and numerical models, (iii) the salt dome scale, to model the far [...]
An anisotropic equation of state for high pressure, high temperature applications
Published: 2021-09-25
Subjects: Condensed Matter Physics, Geophysics and Seismology, Materials Science and Engineering, Mineral Physics, Physical Sciences and Mathematics, Planetary Geophysics and Seismology, Planetary Mineral Physics
This paper presents a strategy for consistently extending isotropic equations of state to model anisotropic materials over a wide range of pressures and temperatures under nearly hydrostatic conditions. The method can be applied to materials of arbitrary symmetry. The paper provides expressions for the deformation gradient tensor, the lattice parameters, the isothermal elastic compliance tensor [...]
Fluid invasion dynamics in porous media with complex wettability and connectivity
Published: 2021-06-17
Subjects: Chemical Engineering, Complex Fluids, Earth Sciences, Fluid Dynamics, Hydrology, Materials Science and Engineering, Other Materials Science and Engineering, Petroleum Engineering, Transport Phenomena
Multiphase flow is important for many natural and engineered processes in subsurface geoscience. Pore-scale multiphase flow dynamics are commonly characterized by an average balance of driving forces. However, significant local variability in this balance may exist inside natural, heterogeneous porous materials, such as rocks and soils. Here, we investigate multiphase flow in heterogeneous rocks [...]
A damage model for the frictional shear failure of brittle materials in compression
Published: 2021-05-13
Subjects: Applied Mathematics, Computational Engineering, Earth Sciences, Engineering, Geology, Materials Science and Engineering, Physical Sciences and Mathematics
Damage models have been successfully employed for many decades in the modelling of tensile failure, where the crack surfaces separate as a crack grows. The advantage of this approach is that crack trajectories can be computed simply and efficiently on a fixed finite element mesh without explicit tracking. The development of damage models for shear failure in compression, where the crack faces [...]
Linking elastic and electrical properties of rocks using cross-property DEM
Published: 2020-10-22
Subjects: Earth Sciences, Engineering Science and Materials, Geophysics and Seismology, Materials Science and Engineering, Physical Sciences and Mathematics
Joint electrical-elastic rock physics modelling can be instrumental in lowering uncertainty in subsurface reservoir characterisation. Typical electrical-elastic cross-property models, however, are empirical or require an intermediate step of porosity estimation to link a rock's electrical and elastic moduli, which can be error-prone away from well controls. Another outstanding issue in [...]
Predicting the yield stress of a 3D printed porous material from its internal structure
Published: 2020-05-12
Subjects: Engineering, Materials Science and Engineering, Structural Materials
The design of any engineering structure requires the knowledge, and therefore determination, of the yield, i.e. limit of elasticity, for the building material. Whilst destructive experimental testing is currently necessary to do so, our work is part of initiatives which aim at deriving the yield without such laboratory experiments. The seminal work of Gurson (1977) on a simplified pore structure, [...]
A note on the instability and pattern formation of shrinkage cracks in viscoplastic soils
Published: 2019-11-07
Subjects: Civil and Environmental Engineering, Engineering, Materials Science and Engineering
In this note we present a theoretical study on the conditions for the onset of cracks, as well as the corresponding pattern formation, in saturated viscoplastic soils under isotropic loading (extension). The type of stress applied is left unspecified, to cover a variety of loadings including shrinkage due to dessication, isotropic thermal expansion, mechanical loading and so forth. By treating [...]
Imbibition in porous media: correlations of displacement events with pore-throat geometry and the identification of a new type of pore snap-off
Published: 2019-08-23
Subjects: Chemical Engineering, Civil and Environmental Engineering, Complex Fluids, Dynamics and Dynamical Systems, Engineering, Engineering Science and Materials, Environmental Engineering, Materials Science and Engineering, Mechanics of Materials, Petroleum Engineering, Transport Phenomena
The displacement of a non-wetting fluid by a wetting fluid in porous media, called imbibition, is important in many natural and industrial processes. During imbibition, the wetting fluid invades the pore space through a series of competitions between piston-like displacement, film and corner flow, snap-off, pore bypassing and trapping. Our understanding of these fundamental pore-scale [...]
A Temperature- and Pressure-Sensitive Visco-Plasticity Theory based on Interface Mechanisms for Sedimentary Rocks
Published: 2019-05-24
Subjects: Civil and Environmental Engineering, Engineering, Geotechnical Engineering, Materials Science and Engineering, Other Materials Science and Engineering
Constitutive modelling in geotechnical engineering and applied earth sciences is facing the challenge of assessing the long-term potential of both man-made and natural geohazards. This involves designing engineering operations for length scales and timescales well beyond those observable in the laboratory. In order to bridge the gap between scales, study rock behaviours well beyond their yield [...]
A spatially resolved fluid-solid interaction model for dense granular packs/Soft-Sand.
Published: 2019-05-09
Subjects: Earth Sciences, Engineering, Materials Science and Engineering, Physical Sciences and Mathematics
Fluid flow through dense granular packs or soft sands can be described as a Darcy s flow for low injection rates, as the friction between grain-grain and grain-walls dominate the solid system behaviour. For high injection rates, fluid forces can generate grain displacement forming flow channels or ``fractures, which in turn modify local properties within the system, such as permeability and [...]