... There has been increasing use of the point load index as a measure of rock strength since its introduction in 1972. The test results have been correlated to in the uniaxial compressive strength σ f of the rock. The correlations between the rates of point load index I s and the uniaxial...

... A constitutive law for natural rock salt is given that describes the relationship among strain rate, stress rate, stress, temperature, and time. Tests required to evaluate the constitutive parameters are identified, and procedures for performing these tests are described. Results are presented...

... Measurements of steady state creep rates and activation parameters are described for rock salt at low temperature ( T ≤ 0.4 T m ; where T m is melting temperature) and low strain rates. The determinations of steady state creep rates rely on the evaluation of upper and lower bounds...

... Measurements of dynamic properties of rock at high temperatures and pressures have many applications to geology and solid earth geophysics. Elastic wave velocities are obtained from rock cylinders in which delay times are measured using a pulse transmission technique. The longitudinal and shear...

... of stress and temperature in a specimen of rock having a volume of 8 m 3 . The heated block test is a logical candidate to obtain information on repository design and licensing, particularly for validating predictive repository model performance. A description is given of the preparation, field work...

... Hard rocks are significantly weakened or fatigued when subjected to cyclic loading. In uniaxial tension and in uniaxial compression the fatigue strength for 10 5 cycles is 60 to 80 percent of the monotonic strength. In triaxial compression the fatigue strength rises as the confining pressure...

... This paper presents a review of the effects of four factors in specimen preparation that influence mechanical property tests—moisture content, orientation with respect to rock fabric, fractures, and specimen tolerances—and discusses methods developed during various Bureau of Mines testing...

... Samples must be representative and specimen preparation must introduce as few changes as possible if microscopic information is to be significant in characterization and classification of soils and rocks and in interpretation of their engineering behavior. Soils and recent sediments are damaged...

... nondestructive tests soil properties soil dynamics rocks moisture content J. T. Lewis I and E. L. Krirlitzsky I Neutron Radiation in the Study of Soil and Rock REFERENCE: Lewis, J. T. and Krinitzsky, E. L., "Neutron Radiation in the Study of Soil and Rock," Practical Applications of Neutron Radiography...

... projects, associated with underground gas storage and longwall coal mining, presently underway by the writer are described. acoustics emission microseisms rock mechanics mining gas storage slopes hydrofracturing geologic structures rocks tests stability rock bursts H. R. Hardy, Jr. 1...

... We describe a new technique for measuring the deformation and load bearing capability of large intact and jointed in situ rock specimens under applied uniaxial stress. The specimen configuration is an equilateral triangular prism of constant cross section with one end still connected...

..., but some information occurs often enough to be of significant value and should be used together with the creep and modulus values. rocks rock mechanics stress strain diagrams rock tests deformation modulus of elasticity creep tests Interpretation of Plate Loading Test .Results D. J. Dodds 1...

... are used to apply desired loads to prepared rock surfaces within a tunnel is described. Instrumentation to measure resulting displacement is referenced within the rock mass and is independent of the loading system. Details of all phases of conducting the tests are presented. In addition, a discussion...

... The available results from radial jacking and dilatometer tests are inadequate for the proper assessment and comparison of the reliability of these test procedures. In order to arrive at a rational evaluation of such tests, a computer program was devised to simulate a jointed rock mass, and sets...

..., and casing spiral. A laboratory device is described which is capable of checking the calibration of inclinometers, the effect of drift on instrument output, and the effect of cross sensitivity on measured angles. Results of the laboratory evaluation of two inclinometer systems are presented. rocks...

... An “Engineering Index” has been developed, (Aufmuth, 1972) for use at field sites, by means of which the pertinent characteristics of the intact and in situ rock mass may be presented in a brief, clear, and relevant manner. The Engineering Index consists of two parts; a lithologic...

... This paper presents an overview of a systematic approach for the evaluation of the geology and rock properties of field sites used for fragmentation tests. Comprehensive flow diagrams illustrate the steps involved in selecting sites for field tests, and in evaluating the results of field rock...

... A mathematical model is given for stress determination in inhomogeneous rock with special reference to a triaxial strain cell. The practical effects of variations in the form and the positioning of the straingage rosettes is considered. Four-element rosettes are shown to provide an estimate...

... A radio frequency roof failure warning device has been designed by the Bureau of Mines, Spokane Mining Research Center, that can be easily installed in a standard rockbolt hole drilled into a mine roof or rib. The device will monitor deformation of the exposed rock surface with respect...

... The torsional shear test consists of applying a torque to a cylindrical core of rock isolated from a rock mass, by means of a diamond drill. The core is restrained by means of an axial rock bolt which is used to apply a controlled normal load. The core is gripped in an apparatus and twisted...