Showing papers in "International Journal of Rock Mechanics and Mining Sciences & Geomechanics Abstracts in 1991"

TL;DR: In this article, the Navier-Stokes equations that govern fluid flow are reduced to the more tractable Reynolds equation, which is valid for low Reynolds numbers and under certain restrictions on the magnitude of the roughness.

TL;DR: In this article, a sliding crack model is proposed to predict the dependence of the stress-strain curve on the applied strain rate, and the model is able to predict both transient and tertiary creep in brittle rocks.

TL;DR: In this article, the influence of pore pressure on tensile fracture initiation and propagation direction was analyzed and the experimental results were presented to describe the influence on the fracture initiation in very porous rocks.

TL;DR: Geotechnics of waste fills, Geotechnical of waste fill, geotechnic of waste filling as discussed by the authors, geotechasechnics in waste fill.

TL;DR: In this article, it was shown that shear band formation under plane-strain conditions occurs in the hardening regime, that is, when the hardness is still positive, and that initial localization is accomodated by rigid-body grain motions through the matrix.

TL;DR: In this paper, the size effect method, previously developed for concrete and mortar, is demonstrated for rock and the measured maximum load values are used to obtain fracture energy, fracture toughness and effective size of the fracture process zone.

TL;DR: In this paper, a new theory is presented to interpret the breakdown pressure which is the wellbore pressure at fracture initiation in hydraulic fracturing tectonic stress measurements, and the theory is able to explain the effects of well-bore diameter and pressurization rate on breakdown pressure.

TL;DR: In this article, a constitutive model based on the theory of plasticity is presented for characterizing the mechanical response of simulated joints under monotonic loading, unloading and reverse loading.

TL;DR: In this paper, an empirical equation relating velocity to confining pressure is proposed, which is used to curve-fit Vp and Vs data for a range of samples and is shown to give excellent results with well-constrained parameters.

TL;DR: In this article, the authors present experimental evidence of the Class I "ductile" vs the Class II "brittle" response observed on the global level for rock and rock-like materials.

TL;DR: In this article, the authors proposed an approach in which the model is strongly conditioned by geology and geophysics, and the hydraulic behavior of these features is then obtained using an inverse technique called simulated annealing.

TL;DR: Schmidt hammer has increasingly been used world-wide as an index test for a quick rock strength and deformability characterization as discussed by the authors, mainly due to its rapidity and easyness in execution, non destructiveness, simplicity, portability and low cost.

TL;DR: In this paper, a hierarchical approach was proposed to model the tunnel-support interaction during the excavation/construction process during the tunnelling in a rock mass with rheological properties.

TL;DR: In this article, the stress distributions around a circular well in granular elastoplastic impermeable media are calculated and the final volumetric strain around the borehole is solved as the summation of the incremental strains due to the injection preceding hydraulic fracture, and the existing plastic strains created during borehole excavation.

TL;DR: In this paper, a time-dependent model of tunnel convergence for tunnelling in a viscoelastic rock mass is proposed to model the excavation-construction process during tunnel construction in a rock mass with rheological properties.

TL;DR: In this paper, a Coulomb layer (sand) overlying a Newtonian ductile layer (silicone) was constructed to investigate how faults in a cover sequence become reactivated when an underlying basement fault is itself reactivated in strike-slip mode.

TL;DR: In this article, the authors present the results from numerical simulations of the complete process of fracture initiation, propagation, closure and reopening, using a specially developed numerical procedure that includes a nonlinear, Dugdale-Barenblatt fracture model, a poroelastic model for the rock mass, and full coupling between fluid flow in the fracture and the mass.

TL;DR: In this paper, a case study of work at the Nevada Test Site and documents the variations in the stress field due to geologic features, such as topography, bedding and faults.

TL;DR: In this paper, a conceptual colloids-metal transport model (COMET) is developed and incorporated into EPA's CML model, a model that simulates solute migration from a landfill in the unsaturated zone to a receptor (i.e., drinking-water well) in the saturated zone.

TL;DR: In this paper, the influence of microcracks on overcore results was investigated using data from 81 overcore tests using the continually monitored Council for Scientific and Industrial Research triaxial strain cell.