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Analysis of the rock mechanics properties of volcanic tuff units from Yucca Mountain, Nevada Test Site

Description: Over two hundred fifty mechanical experiments have been run on samples of tuff from Yucca Mountain, Nevada Test Site. Cores from the Topopah Spring, Calico Hills, Bullfrog and Tram tuff units were deformed to collect data for an initial evaluation of mechanical (elastic and strength) properties of the potential horizons for emplacement of commercial nuclear wastes. The experimental conditions ranged in sample saturation from room dry to fully saturated, confining pressure from 0.1 to 20 MPa, pore pressure from 0.1 to 5 MPa, temperature from 23 to 200{sup 0}C, and strain rate from 10{sup -7} to 10{sup -2} s{sup -1}. These test data have been analyzed for variations in elastic and strength properties with changes in test conditions, and to study the effects of bulk-rock characteristics on mechanical properties. In addition to the site-specific data on Yucca Mountain tuff, mechanical test results on silicic tuff from Rainier Mesa, Nevada Test Site, are also discussed. These data both overlap and augment the Yucca Mountain tuff data, allowing more definitive conclusions to be reached, as well as providing data at some test conditions not covered by the site-specific tests.
Date: August 1, 1983
Creator: Price, R. H.
Partner: UNT Libraries Government Documents Department

X-ray microscopy using grazing-incidence reflection optics

Description: The Kirkpatrick-Baez microscopes are described along with their role as the workhorse of the x-ray imaging devices. This role is being extended with the development of a 22X magnification Kirkpatrick-Baez x-ray microscope with multilayer x-ray mirrors. These mirrors can operate at large angles, high x-ray energies, and have a narrow, well defined x-ray energy bandpass. This will make them useful for numerous experiments. However, where a large solid angle is needed, the Woelter microscope will still be necessary and the technology needed to build them will be useful for many other types of x-ray optics.
Date: August 6, 1981
Creator: Price, R.H.
Partner: UNT Libraries Government Documents Department

X-ray microscopy using grazing-incidence reflections optics

Description: The role of Kirkpatrick-Baez microscopes as the workhorse of the x-ray imaging devices is discussed. This role is being extended with the development of a 22X magnification Kirkpatrick-Baez x-ray microscope with multilayer x-ray mirrors. These mirrors can operate at large angles, high x-ray energies, and have a narrow, well defined x-ray energy bandpass. This will make them useful for numerous experiments. However, where a large solid angle is needed, the Woelter microscope will still be necessary and the technology needed to build them will be useful for many other types of x-ray optics.
Date: June 30, 1983
Creator: Price, R.H.
Partner: UNT Libraries Government Documents Department

High image quality sub 100 picosecond gated framing camera development

Description: A major challenge for laser fusion is the study of the symmetry and hydrodynamic stability of imploding fuel capsules. Framed x-radiographs of 10-100 ps duration, excellent image quality, minimum geometrical distortion (< 1%), dynamic range greater than 1000, and more than 200 x 200 pixels are required for this application. Recent progress on a gated proximity focused intensifier which meets these requirements is presented.
Date: November 17, 1983
Creator: Price, R.H. & Wiedwald, J.D.
Partner: UNT Libraries Government Documents Department

Kirkpatrick-Baez x-ray-microscope optimization for inertial-confinement-fusion applications

Description: Analytic approximations have been used to optimize single-channel and four-channel Kirkpatrick-Baez (K-B) x-ray microscopes in three ways: (I) for best effective solid angle at best resolution, (II) for best effective solid angle at a given resolution worse than the best; and (III) for best effective solid angle at a specified breadth of field. All optimizations are also made consistent with clean channel response, to ensure that any high-energy second peak will be small compared with the primary channel response. This is achieved at a sacrifice of effective solid angle. We describe a cross-talk aberration not previously recognized in K-B x-ray microscopes. The analytic approximations presented in this paper, which desribe the optical and constructional parameter of optimized K-B x-ray microscopes, are intended to allow scaling and localization in parameter space from which detailed numerical calculations can be used to fine-tune a microscope design.
Date: May 1, 1983
Creator: Price, R.H. & Priedhorsky, W.C.
Partner: UNT Libraries Government Documents Department

Miniature x-ray point source for alignment and calibration of x-ray optics

Description: A miniature x-ray point source of high brightness similar to that of Rovinsky, et al. is described. One version of the x-ray source is used to align the x-ray optics on the Argus and Shiva laser systems. A second version is used to determine the spatial and spectral transmission functions of the x-ray optics. The spatial and spectral characteristics of the x-ray emission from the x-ray point source are described. The physical constraints including size, intensity and thermal limitations, and useful lifetime are discussed. The alignment and calibration techniques for various x-ray optics and detector combinations are described.
Date: November 1, 1977
Creator: Price, R.H.; Boyle, M.J. & Glaros, S.S.
Partner: UNT Libraries Government Documents Department

Gold transmission gratings with submicrometer periods and thickness > 0. 5. mu. m

Description: Gold gratings with spatial periods of 0.3 and 0.2 ..mu..m have been fabricated in thicknesses of 0.6 and 0.25 ..mu..m, respectively, and used in x-ray spectroscopy and spatial-period-division. Fabrication techniques included: holographic lithography, shadowing, x-ray lithography and gold microplating. Control of linewidth to tolerances of the order of 10 nm has been demonstrated for gratings of 0.2 ..mu..m period. A high resolution imaging spectrometer, composed of a 22x Wolter x-ray microscope in conjunction with a gold transmission grating, was tested. At a wavelength of 0.69 nm a resolving power, lambda/..delta.. lambda, of 200 was demonstrated. Resolution in this case was source size limited. Gratings of 99.5 nm period were exposed in PMMA by x-ray (lambda = 4.5 nm) spatial-period-division.
Date: December 1, 1981
Creator: Ceglio, N.M.; Price, R.H.; Hawryluk, A.M.; Melngailis, J. & Smith, H.I.
Partner: UNT Libraries Government Documents Department

Bulk and mechanical properties of the Paintbrush tuff recovered from borehole USW NRG-6: Data report

Description: Experimental results are presented for bulk and mechanical properties measurements on specimens of the Paintbrush tuff recovered from borehole USW NRG-6 at Yucca Mountain, Nevada. Measurements have been performed on four thermal/mechanical units, TCw, PTn, TSw1 and TSw2. On each specimen the following bulk properties have been reported: dry bulk density, saturated bulk density, average grain density, and porosity. Unconfined compression to failure, confined compression to failure, and indirect tensile strength tests were performed on selected specimens recovered from the borehole. In addition, compressional and shear wave velocities were measured on specimens designated for unconfined compression and confined compression experiments. Measurements were conducted at room temperature on nominally water saturated specimens; however, some specimens of PTn were tested in a room dry condition. The nominal strain rate for the fracture experiments was 10{sup -5} s {sup -1}.
Date: November 1, 1994
Creator: Martin, R.J.; Boyd, P.J.; Noel, J.S. & Price, R.H.
Partner: UNT Libraries Government Documents Department

Variability of the physical properties of tuff at Yucca Mountain, NV

Description: Lateral and vertical variabilities in the bulk and mechanical properties of silicic volcanic tuff at the potential nuclear waste repository site in Yucca Mountain, NV have been evaluated. Laboratory measurements have been performed on tuff specimens recovered from boreholes located to support the design of the Exploratory Studies Facility/North Ramp. The data include dry and saturated bulk densities, average grain density, porosity, compressional and shear wave velocities, elastic moduli, and compressional and tensional fracture strengths. Data from eight boreholes aligned in a northwest-southeast direction have been collected under the required quality assurance program. Three boreholes have penetrated the potential repository horizon. The information collected provides for an accurate appraisal of the variability of rock properties in the vicinity of the boreholes. As expected, there is substantial variability in the bulk and mechanical properties of the tuff with depth (lithology). This is due to variations in gross characteristics of the tuffs (e.g., cooling units, mode of deposition, etc.), as well as smaller scale features (welding, porosity, and internal structures) that have developed as a result of depositional and post-depositional mechanisms. An evaluation of the lateral variability in bulk and mechanical properties is somewhat limited, at this time, due to a lack of borehole control to the north and south (parallel to the depositional flow direction). Initial observations indicate that there is minimal lateral variability within lithologic units. There are observable differences however, that can be related to variability in specific properties (e.g., porosity, and internal structures).
Date: December 31, 1994
Creator: Boyd, P. J.; Martin, R. J., III & Price, R. H.
Partner: UNT Libraries Government Documents Department

An experimental comparison of laboratory techniques in determining bulk properties of tuffaceous rocks; Yucca Mountain Site Characterization Project

Description: Samples of tuffaceous rock were studied as part of the site characterization for a potential nuclear waste repository at Yucca Mountain in southern Nevada. These efforts were scoping in nature, and their results, along with those of other investigations, are being used to develop suitable procedures for determining bulk properties of tuffaceous rock in support of thermal and mechanical properties evaluations. Comparisons were made between various sample preparation, handling, and measurement techniques for both zeolitized and nonzeolitized tuff in order to assess their effects on bulk property determinations. Laboratory tests included extensive drying regimes to evaluate dehydration behavior, the acquisition of data derived from both gas and water pycnometers to compare their suitability in determining grain densities, a comparison of particle size effects, and a set of experiments to evaluate whole core saturation methods. The results affirm the added complexity of these types of measurements where there is a zeolite component in the sample mineralogy. Absolute values for the bulk properties of zeolitized tuff are immeasurable due to the complex nature of their dehydration behavior. However, the results of the techniques that were investigated provide a basis for the development of preferred, consistent methods for determining the grain density, dry and saturated bulk densities, and porosity of tuffaceous rock, including zeolitic tuff in support of thermal and mechanical properties evaluations.
Date: April 1, 1994
Creator: Boyd, P.J.; Martin, R.J. III & Price, R.H.
Partner: UNT Libraries Government Documents Department

Calculation of experiment uncertainty in laboratory determination of several geoengineering properties of tuffs from Yucca Mountain, Nevada; Yucca Mountain Site Characterization Project

Description: A method for estimating the precision and accuracy of measured parameters is described. Examples of application of the estimating method are presented for density, porosity, compressive strength, Young`s modulus, Poisson`s ratio, and thermal expansion. With the exception of the coefficient of linear thermal expansion, all laboratory data for these properties for tuff samples appear to have reasonable experiment uncertainties. Uncertainties in the thermal-expansion coefficients may be as high as 39% of the values, although most uncertainties for the coefficients are probably {le}2%. 4 refs., 1 fig., 15 tabs.
Date: November 1, 1991
Creator: Nimick, F.B.; Schwartz, B.M. & Price, R.H.
Partner: UNT Libraries Government Documents Department

Thermal expansion as a function of confining pressure for welded tuff from Yucca Mountain

Description: Thermal expansion measurements were conducted as a function of confining pressure on welded specimens of Topopah Spring Member tuff recovered from borehole USW SD-12 at Yucca Mountain, NV. Each specimen was tested at confining pressures between 1 and 30 MPa over a nominal temperature range of 25 to 250{degrees}C. On several specimens, the higher confining pressure thermal cycles were performed first to inhibit thermal effects, such as cracking, that occur at lower confining pressures in other rock types. The coefficient of thermal expansion for welded tuff increases with temperature. At temperatures below 100 {times} C the mean coefficient of thermal expansion range from 7.7 to 10.8 {times} 10{sup {minus}6}{sup C {minus}1}. As temperatures approach 250{degrees}C, the thermal expansions increase markedly to values of 14.2 to 20.6 {times} 10{sup {minus}6}{degrees}{sup C{minus}1}. The effect of confining pressure on thermal expansion for tuff is small.
Date: February 1, 1996
Creator: Martin, R.J.; Noel, J.S.; Boyd, P.J. & Price, R.H.
Partner: UNT Libraries Government Documents Department

Effect of boundary conditions on the strength and deformability of replicas of natural fractures in welded tuff; Data report: Yucca Mountain Site Characterization Project

Description: Four series of cyclic direct-shear experiments were conducted on several replicas of three natural fractures and a tensile fracture of welded tuff from Yucca Mountain. The objective of these tests was to examine the effect of cyclic loading on joint shear behavior under different boundary conditions. The shear tests were performed under either different levels of constant normal load ranging between 0.6 and 25.6 kips (2.7 and 113.9 kN) or constant normal stiffness ranging between 14.8 and 187.5 kips/in (25.9 and 328.1 kn/cm) . Bach test in the two categories consisted of five cycles of forward and reverse shear. Normal compression tests were also performed both before and after each shear experiment to measure changes in joint normal deformability. In order to quantify fracture surface damage during shear, fracture-surface fractal dimensions were obtained from measurements before and after shear.
Date: September 1, 1993
Creator: Wibowo, J.; Amadei, B.; Sture, S.; Robertson, A.B. & Price, R.H.
Partner: UNT Libraries Government Documents Department

The effect of frequency on Young`s modulus and seismic wave attenuation

Description: Laboratory experiments were performed to measure the effect of frequency, water-saturation, and strain amplitude on Young`s modulus and seismic wave attenuation on rock cores recovered on or near the site of a potential nuclear waste repository at Yucca Mountain, Nevada. The purpose of this investigation is to perform the measurements using four techniques: cyclic loading, waveform inversion, resonant bar, and ultrasonic velocity. The measurements ranged in frequency between 10{sup {minus}2} and 10{sup 6} Hz. For the dry specimens Young`s modulus and attenuation were independent of frequency; that is, all four techniques yielded nearly the same values for modulus and attenuation. For saturated specimens, a frequency dependence for both Young`s modulus and attenuation was observed. In general, saturation reduced Young`s modulus and increased seismic wave attenuation. The effect of strain amplitude on Young`s modulus and attenuation was measured using the cyclic loading technique at a frequency of 10{sup {minus}1} Hz. The effect of strain amplitude in all cases was small. For some rocks, such as the potential repository horizon of the Topopah Spring Member tuff (TSw2), the effect of strain amplitude on both attenuation and modulus was minimal.
Date: July 1, 1994
Creator: Price, R.H.; Martin, R.J. III & Haupt, R.W.
Partner: UNT Libraries Government Documents Department

Characterization of porosity in support of mechanical property analysis

Description: Previous laboratory investigations of tuff have shown that porosity has a dominant, general effect on mechanical properties. As a result, it is very important for the interpretation of mechanical property data that porosity is measured on each sample tested. Porosity alone, however, does not address all of the issues important to mechanical behavior. Variability in size and distribution of pore space produces significantly different mechanical properties. A nondestructive technique for characterizing the internal structure of the sample prior to testing is being developed and the results are being analyzed. The information obtained from this technique can help in both qualitative and quantitative interpretation of test results.
Date: December 31, 1992
Creator: Price, R.H.; Martin, R.J. III & Boyd, P.J.
Partner: UNT Libraries Government Documents Department

Effect of boundary conditions on the strength and deformability of replicas of natural fractures in welded tuff: Comparison between predicted and observed shear behavior using a graphical method; Yucca Mountain Site Characterization Project

Description: Four series of cyclic direct-shear experiments were conducted on several replicas of three natural fractures and a laboratory-developed tensile fracture of welded tuff from Yucca Mountain to test the graphical load-displacement analysis method proposed by Saeb (1989) and Amadei and Saeb (1990). Based on the results of shear tests conducted on several joint replicas under different levels of constant normal load ranging between 0.6 and 25.6 kips (2.7 and 113.9 kN), the shear behavior of joint replicas under constant normal stiffness ranging between 14.8 and 187.5 kips/in. (25.9 and 328.1 kN/cm) was predicted by using the graphical method. The predictions were compared to the results of actual shear tests conducted for the same range of constant normal stiffness. In general, a good agreement was found between the predicted and the observed shear behavior.
Date: September 1, 1993
Creator: Wibowo, J.; Amadei, B.; Sture, S.; Robertson, A.B. & Price, R.H.
Partner: UNT Libraries Government Documents Department

Text for Mechanical and bulk properties in support of ESF design issues

Description: An intensive laboratory investigation is being performed to determine the mechanical properties of tuffs for the Yucca Mountain Site Characterization Project (YMP). Most recently, experiments are being performed on tuff samples from a series of drill holes along the proposed alignment of the Exploratory Study Facilities (ESF) north ramp. Unconfined compression and indirect tension experiments are being performed and the results are being analyzed with the help of bulk property information. The results on samples from five of the drill holes are presented here. In general, the properties vary widely, but are highly dependent on the sample porosity.
Date: July 1, 1994
Creator: Price, R.H.; Martin, R.J.; Boyd, P.J. & Noel, J.S.
Partner: UNT Libraries Government Documents Department

Effect of boundary conditions on the strength and deformability of replicas of natural fractures in welded tuff: Data analysis

Description: Assessing the shear behavior of intact rock & rock fractures is an important issue in the design of a potential nuclear waste repository at Yucca Mountain Nevada. Cyclic direct shear experiments were conducted on replicas of three natural fractures and a laboratory-developed tensile fracture of welded tuff. The tests were carried out under constant normal loads or constant normal stiffnesses with different initial normal load levels. Each test consisted of five cycles of forward and reverse shear motion. Based on the results of the shear tests conducted under constant normal load, the shear behavior of the joint replicas tested under constant normal stiffness was predicted by using the graphical analysis method of Saeb (1989), and Amadei and Saeb (1990). Comparison between the predictions and the actual constant stiffness direct shear experiment results can be found in a report by Wibowo et al. (1993b). Results of the constant normal load shear experiments are analyzed using several constitutive models proposed in the rock mechanics literature for joint shear strength, dilatancy, and joint surface damage. It is shown that some of the existing models have limitations. New constitutive models are proposed and are included in a mathematical analysis tool that can be used to predict joint behavior under various boundary conditions.
Date: April 1, 1994
Creator: Wibowo, J.; Amadei, B.; Sture, S. & Price, R.H.
Partner: UNT Libraries Government Documents Department

Bulk and mechanical properties of the Paintbrush tuff recovered from borehole USW NRG-7/7A: Data report. Yucca Mountain Site Characterization Project

Description: An integral part of the licensing procedure for the potential nuclear waste repository at Yucca Mountain, Nevada, involves prediction of the in situ rheology for the design and construction of the facility and the emplacement of canisters containing radioactive waste. The data used to model the thermal and mechanical behavior of the repository and surrounding lithologies include dry and saturated bulk densities, average grain density, porosity, compressional and shear wave velocities, elastic moduli, and compressional and tensional fracture strengths. In this study, a suite of experiments was performed on cores recovered from the USW NRG-717A borehole drilled in support of the Exploratory Studies Facility (ESF) at Yucca Mountain. USW NRG-7/7A was drilled to a depth of 1,513.4 feet through five thermal/mechanical units of Paintbrush tuff and terminating in the tuffaceous beds of the Calico IEUS. The thermal/mechanical stratigraphy was defined by Orfiz et al. to group rock horizons of similar properties for the purpose of simplifying modeling efforts. The relationship between the geologic stratigraphy and the thermal/mechanical stratigraphy is presented. The tuff samples in this study have a wide range of welding characteristics, and a smaller range of mineralogy and petrology characteristics. Generally, the samples are silicic, ash-fall tuffs that exhibit large variability in their elastic and strength properties.
Date: May 1, 1995
Creator: Martin, R.J.; Boyd, P.J.; Noel, J.S. & Price, R.H.
Partner: UNT Libraries Government Documents Department

Ultrafast gated intensifier design for laser fusion x-ray framing applications

Description: A major challenge for laser fusion is the study of the symmetry and the hydrodynamic stability of imploding fuel capsules. Streaked x-radiography, in one space and one time dimension, does not provide sufficient information. Two (spatial) dimensional frames of 10 to 100 ps duration are required with good image quality, minimum geometrical distortion (approximately 1%), dynamic range greater than 1000 and greater than 200 x 200 pixels. A gated transmission line imager (TLI) can meet these requirements with frame times between 30 and 100 ps. An instrument of this type is now being developed. Progress on this instrument including theory of operation, ultrafast pulse generation and propagation, component integration, and high resolution phosphor screen development are presented.
Date: November 1, 1983
Creator: Price, R.H.; Wiedwald, J.D.; Kalibjian, R.; Thomas, S.W. & Cook, W.M.
Partner: UNT Libraries Government Documents Department

Quasi-static rock mechanics data for rocksalt from three Strategic Petroleum Reserve domes

Description: Triaxial compression and extension experiments have been run on rocksalt samples from three Strategic Petroleum Reserve (SPR) domes. Seventeen quasi-static tests were loaded at mean stress rates of .66 to 1.04 psi/sec (4.5 to 7.2 kPa/sec), confining pressures of 14.5 to 2000 psi (0.1 to 13.8 MPa) and temperatures of 22 to 100/sup 0/C. Eleven of the test specimens were from Bryan Mound, Texas, and three each were from Bayou Choctaw, Louisiana, and West Hackberry, Louisiana. In general, the resulting mechanical data from the three domes are similar, and they are consistent with previously published data. Ultimate sample strengths are directly related to confining pressure (least principal stress) and indirectly related to temperature, while ductility increases with both pressure and temperature.
Date: December 1, 1981
Creator: Price, R.H.; Wawersik, W.R.; Hannum, D.W. & Zirzow, J.A.
Partner: UNT Libraries Government Documents Department

Mechanical and bulk properties of intact rock collected in the laboratory in support of the Yucca Mountain Site Characterization Project

Description: A comprehensive laboratory investigation is determining the mechanical properties of tuffs for the Yucca Mountain Site Characterization Project (YMP). Most recently, experiments have been performed on tuff samples from a series of drill holes along the planned alignment of the Exploratory Study Facilities (ESF) north ramp. Unconfined compression and indirect tension experiments were performed and the results are being analyzed with the help of bulk property information. The results on samples from eight of the drill holes are presented. In general, the properties vary widely, but are highly dependent on the sample porosity. The developed relationships between mechanical properties and porosity are powerful tools in the effort to model the rock mass response of Yucca Mountain to the emplacement of the potential high-level radioactive waste repository.
Date: November 1994
Creator: Price, R. H.; Martin, R. J., III; Boyd, P. J. & Boinott, G. N.
Partner: UNT Libraries Government Documents Department

Anisotropy of the Topopah Spring Member Tuff

Description: Mechanical properties of the tuffaceous rocks within Yucca Mountain are needed for near and far-field modeling of the potential nuclear waste repository. If the mechanical properties are significantly anisotropic (i.e., direction-dependent), a more complex model is required. Relevant data from tuffs tested in earlier studies indicate that elastic and strength properties are anisotropic. This scoping study confirms the elastic anisotropy and concludes some tuffs are transversely isotropic. An approach for sampling and testing the rock to determine the magnitude of the anisotropy is proposed.
Date: July 1, 1992
Creator: Martin, R.J. III; Boyd, P.J.; Haupt, R.W. & Price, R.H.
Partner: UNT Libraries Government Documents Department

Unconfined compression experiments on Topopah Spring Member tuff at 22{degrees}C and a strain rate of 10{sup {minus}9} s{sup {minus}1}: Data report; Yucca Mountain Site Characterization Project

Description: Experiment results are presented for unconfined compressive strength and elastic moduli of tuffaceous rocks from Busted Butte near Yucca Mountain, Nevada. The data have been compiled for the Yucca Mountain Site Characterization Project Site and Engineering Properties Data Base. Experiments were conducted on water-saturated specimens of the potential nuclear waste repository horizon Topopah Spring Member tuff (thermal/mechanical unit TSw2). The influence of strain rate on mechanical properties of the tuff was examined by loading six specimens in uniaxial compression at a strain rate of 10{sup {minus}9} s{sup {minus}1}. The experiments performed under ambient pressure and temperature conditions and conformed to Technical Procedure 91, titled ``Unconfined Compression Experiments at 22{degrees}C and a Strain Rate of 10{sup {minus}9} s{sup {minus}1}.`` The mean and standard deviation values of ultimate strength, Young`s modulus and Poisson`s ratio determined from these experiments are 85.4{plus_minus}21.7 MPa, 33.9{plus_minus}4.6 GPa, and 0.09{plus_minus}0.07, respectively.
Date: August 1, 1993
Creator: Martin, R.J. III; Boyd, P.J.; Noel, J.S. & Price, R.H.
Partner: UNT Libraries Government Documents Department