Showing papers in "International Journal of Rock Mechanics and Mining Sciences & Geomechanics Abstracts in 1973"

TL;DR: A suite of triaxial compression tests was done, using specimens of a fine-grained argillaceous quartzite measuring 25 mm in diameter by 75 mm in length, in which compression was stopped at predetermined points along the complete stress-strain curve, especially in the vicinity of and beyond its peak as discussed by the authors.

TL;DR: In this paper, the authors report the results of a number of fatigue tests on dolomite specimens, and propose a hypothesis to explain the resultant deformation based on a description of rock failure in terms of strain energy-dependent crack propagation.

TL;DR: In this paper, it was shown that tensile stresses are developed inside a rock with staggered compliant joints, and may be as high as twice the overall shear stresses or the overall compressive stresses.

TL;DR: In this paper, the authors used a closed-loop, servocontrolled hydraulic testing machine to study the mechanisms of rock failure and found that applied load relaxes appreciably as soon as macro-cracks initiated at the specimen surfaces.

TL;DR: In this article, normal shear fracture initiation from compressive stress concentration at the periphery of voids and cracks, subjected to compressive loading, is examined experimentally and theoretically.

TL;DR: In this paper, the effects of water saturation on compressional wave velocity, V p, and elastic property anisotropy are investigated omnidirectionally in dry and water-saturated spheres of Barre Granite and Tennessee marble by the ultrasonic pulse method.

TL;DR: In this article, simple models representing churn drilling, down-the-hole drilling and hammer drilling are established and analyzed with respect to the efficiencies (work done on rock/impact energy) of these percussive methods.

TL;DR: In this paper, the results of model blasting experiments in homogeneous granite and limestone showed that rock fragmentation is not controlled by a single explosive property but by a combination of several properties.

TL;DR: In this paper, the authors compare the displacement fields given by an anisotropic continuum model of a jointed rock mass with that obtained from the discrete joint model, and find that the model predicts a stress distribution that is significantly different from Flamant's solution for a strip load on a semi-infinite rock mass.

TL;DR: In this paper, the authors developed a theory to explain the cutting action of water jets having total pressures above 1000 atm, where the surface pressure would suffice to keep the grains in place, but permeability allows the water to penetrate beneath the cutting surface and relieve the pressure across the grains.

TL;DR: In this article, the authors conducted tensile tests on cylindrical rock specimens, cemented to end-caps attached to non-twist cables and found that the initial tangent modulus of rock is similar, both in uniaxia tension and in compression, but in tension the modulus decreases with increase of applied load, whereas in compression modulus increases up to the stage of incipient failure.

TL;DR: A number of Hornblende schists, and associated basic rocks collected from the Kolar Gold Fields, Mysore state, India; from different levels, have been studied in detail in the laboratory as discussed by the authors.

TL;DR: In this paper, the authors determined the three-dimensional stress field at seven locations in an iron mine in the Lake Superior region and showed that the minimum principal compressive stress is directed close to vertical in all cases and that the horizontal stress field can be described in general as isotropic with local variations.

TL;DR: In this article, the authors considered the impact of a cylindrical hammer on a rod and showed that the maximum efficiency can be approximated using a linearized representation of a force-displacement relationship which is nonlinear in the loading region.

TL;DR: A detailed study has revealed three major categories of cataclastic behaviour as discussed by the authors : clean micro cracks, most probably formed during pressure release, microfractures and blunted microcracks.

TL;DR: In this article, a method for deriving the complete force-displacement curve associated with the failure process in any laboratory test is presented with special reference to the beam test, which is incrementally generated by correlating the reduction in specimen modulus with the energy absorption that occurs during crack propagation.

TL;DR: In this article, a mutliaxial test cell was developed to determine the state of deformation by means of proximity detection devices mounted exterior to the specimen. But the test cell is used in testing of coal materials which have anistropic mechanical properties.

TL;DR: In this article, an experimental investigation into the effects of size of cylindrical test specimens on observed axial, lateral and volumetric stress-strain behaviour and strength is described.

TL;DR: In this paper, a literature survey was carried out, revealing that while faults and seams constitute a major cause of instability underground, there is only a limited amount of information on behavior characteristics of gouge material.

TL;DR: In the second series, each having a duration of 1500 hr, are incorporated the effects of the presence of clay seams in the roof and floor as discussed by the authors, and it was found that a pillar diameter-to-height ratio of at least 8 was required to prevent brittle failure at vertical stresses equivalent to depths of 3400 ft.

TL;DR: In this paper, two different models representing a joint between drill rods are analyzed and the efficiencies of stress wave energy transfer derived from the two models are shown to agree well in many situations of interest in hammer drilling, and since the rigid joint model leads to simplified analysis, this model is used in solving two problems.

TL;DR: In this paper, an instrumentation placed ahead of three model tunnels in the laboratory and ahead of a crosscut driven in a metamorphic rock mass detected stress changes several tunnel diameters ahead of the tunnel face.

TL;DR: A compilation of fracture data around underground nuclear explosions is presented in this article, where a least-squares fit of measured chimney height for rock other than alluvium gives the relation h c = 0.88 r c 1.5.

TL;DR: In this paper, the authors determined displacement of roof rocks in the neighbourhood of a moving longwall face in order to define the primary and secondary regions of caving while working seams by longwall mining.

TL;DR: In this article, complete force-displacement curves characterizing the collapse process of plexiglas and rock beams were experimentally obtained in a closed-loop programmable testing system with an appropriate choice of feedback signal.

TL;DR: In this paper, the attenuation of a stress-wave as it propagates through tuffaceous rocks of various porosities and degrees of saturation is investigated by a calculational parameter study.

TL;DR: In this paper, the effects of different lateral latent stress fields and different plan radii of curvature of the slopes on the stress distributions were studied, with particular attention paid to the circumferential stresses in the slope.

TL;DR: In this paper, a digital computer method for calculating the stresses and displacements induced by underground excavations in a single flat-lying seam that is arbitrarily near to the surface of the earth is described.

TL;DR: In this article, the authors outline the rock mechanics investigations associated with Project Salt Vault, a feasibility study of radioactive waste disposal in an underground salt formation, and a theoretical model is developed which is consistent with laboratory and field observations of creep and thermal effects.