Showing papers in "International Journal of Rock Mechanics and Mining Sciences & Geomechanics Abstracts in 1975"

TL;DR: In this paper, the authors evaluated the general flow properties of coal seams under various conditions of applied axial and radial stress and found that the coal seams were strongly stress dependent decreasing by more than two orders of magnitude in the stress range of 250-2000 psi.

TL;DR: In this article, the authors compared theoretical shear-stress distribution along a loaded resin grouted rock anchor, with computed shear stress distributions obtained from tests on instrumented anchors in concrete, limestone and chalk.

TL;DR: In this paper, the value and meaning of large scale in situ in situ tests in compression are discussed based on the authors' experience of 8 years of in situ testing involving 66 large coal speciments (up to 2 m in width and height and with width-to-height ratios from 0·5 to 3·4 ).

TL;DR: In this article, the authors examined the evolution of fracture around cavities subjected to polyaxial compression through a series of model experiments and found that at low confining pressure, the tensile mode dominates with collapse coinciding with the sudden and explosive appearance of the secondary tensile fracture, which in turn is brought about by material failure at compressive stress concentrations.

TL;DR: The transversely isotropic compliance characteristic of three United States coal mine shales is investigated in this paper, where Young's moduli values obtained for ‘dry’ specimens were on the order of two or three times that of the ‘wet' specimens.

TL;DR: In this paper, a facility for studying time-dependent deformation was created at the University of Melbourne to achieve a constant temperature in the creep testing laboratory and a long-term loading machine consisting of a gas-hydraulic system and a loading frame was designed to apply the sustained pressure on the rock specimens.

TL;DR: The effect of the gas pressure from combustion products of an explosive charge on the fracture process was investigated in this article, where two plane models with a centrally located circular charge were examined.

TL;DR: In this paper, the fracture strength and frictional strength of Weber Sandstone have been measured as a function of confining pressure and pore pressure, and it has been shown that fracture strength is independent of lithology.

TL;DR: In this article, the Wissahickon Formation fracture surfaces were examined with the aid of a scanning electron microscope and the contribution of foliation planes, which are considered sources of weakness, was investigated.

TL;DR: In this article, the authors tested various strain rates under uniaxial tension on various types of sandstone, Barre granite, Tennessee marble, and Valder limestone, and found that the strength increased with strain rates but the rates of increase and the shapes of postfailure region of the complete load-deformation curves varied.

TL;DR: In this paper, three stages can be distinguished in the microfracturing radiation, and axial, transverse and volumetric strains ( Σ√ E, ϵ z, ϵ r and Δ V/V, respectively ) for Westerly granite under constant stress.

TL;DR: In this article, the results of a 7-year Bureau of Mines program to review, revise, and make an effective engineering tool of the microseismic method of determining the stability of rock structures are presented.

TL;DR: In this article, a technique is proposed for determining bluntness and wear of rolling disk cutters, which involves making successive measurements of cutter diameter during cutting experiments and comparing them with the original cutter diameter, one half of the difference between these two values in millimeters is defined as bluntness.

TL;DR: In this paper, penetration tests have been carried out in laboratory on coal specimens collected from the complete rank (degree of coalification) of the coal series: lignites, brown coals, bituminous coals and anthracites.