In order to better understand groundwater influx and protection in coal mining extraction works, an in-house water flow apparatus coupled with an industrial rock testing system, known as MTS 815.02, were used to study the effects of grain size mixtures on the compaction and flow properties of disintegrated, or non-cemented, coal samples. From the Reynolds number evaluation of the samples with d...

Circular sawing with diamond-impregnated tools has been extensively used in stone processing plants and prediction of rock sawability is important in the cost estimation and the planning of the plants. Rock sawability depends on machine characteristics, type and diameter of diamond saw, depth of cut, rate of sawing and tool wear, and rock properties. Some researchers have investigated the relat...

The calcarenites carbonate rocks of the Quaternary ridges, which extend along the northwestern Mediterranean coastal plain of Egypt, represent an excellent model for the transformation of loose sediments to real sedimentary rocks by the different stages of meteoric diagenesis. The depositional and diagenetic fabrics of the rocks, in addition to the strata orientation, highly affect their ultima...

wall displacements and ground pressure acting on the lining of a tunnel increase with time. these time-dependent deformations are both due to face advance effect and to the time-dependent behavior of the rock mass.  viscoelastic materials exhibit both viscous and elastic behaviors. thorough this study, the effect of different linear viscoelastic models including maxwell, kelvin and kelvin-voigt...

[1] Anelasticity and diffusion creep viscosity of partially molten rock analogue were measured experimentally at various melt fractions (0.0025–0.04). The presence of even a small quantity of melt phase causes a significant increase in attenuation and dispersion, and decrease in viscosity (melt effect). Similar changes are additionally caused by the presence of a secondary solid component (chem...

An integrated nomenclature scheme is proposed to capture the inherent heterogeneity of fine-grained sedimentary rocks at the 102 to 1023 mm scale and to assist the evaluation of these rocks as sinks of organic carbon, barriers to fluid flows, and reservoirs of oil and gas. This scheme incorporates previous knowledge and the latest field, petrographic, and laboratory observations. We propose to ...

In this paper the influence of microstructure on crack initiation stress and ultimate strength is investigated using results and analysis of 32 triaxial compression tests performed on cylindrical cores of dolomite samples which exhibit a wide range of grain sizes and mosaic textures. All tests were performed at a constant strain rate, under confining pressures between 0 to 40 MPa. The predictiv...

Nanocrystalline materials show a higher strain-rate sensitivity in contrast to the conventional coarse-grained materials and a different grain size dependency. To explain these phenomenon, a finite element model is constructed that considers both grain interior and grain boundary deformation of nanocrystalline materials. The model consist of several crystalline cores with different orientations...

When load is applied to fcc nanograins, leading partial dislocations nucleate at grain boundary steps and propagate into the grain, leaving stacking faults behind. The extent to which these faults expand before a trailing partial is emitted generally does not equal the equilibrium separation distance of the corresponding full dislocation. Here we use a density functional theory – phase field di...