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Analysis of Field Compaction Data: Report 2, Littleville Dam, Westfield River, Massachusetts

Description: Summary: This report is a review of the materials, specifications, procedures, equipment, and testing pertinent to construction and compaction control of the earth-fill embankment of Littleville Dam, Westfield River, Mass., constructed by the U. S. Army Engineer Division, New England.
Date: December 1970
Creator: Torrey, Victor H., III
Partner: UNT Libraries Government Documents Department

Study of Dispersant Agents for Thorium Oxide

Description: S>A preliminary study of dispersing agents for thorium oxide was completed and several of the dispersants have possible uses. Also many of the industrial dispersing agents tested are not usable with thorium oxide due to induced behavior causing balling and caking. The effects of nitric acid concentration were observed to also effect each dispersing agent. (auth)
Date: August 1, 1959
Creator: Bate, L. C. & Leddicotte, G. W.
Partner: UNT Libraries Government Documents Department

Laboratory Characterization of Mechanical and Permeability Properties of Dynamically Compacted Crushed Salt

Description: The U. S. Department of Energy plans to dispose of transuranic wastes at the Waste Isolation Pilot Plant (WIPP), a geologic repository located at a depth of about 655 meters. The WIPP underground facility is located in the bedded salt of the Salado Formation. Access to the facility is provided through vertical shafts, which will be sealed after decommissioning to limit the release of hazardous waste from the repository and to limit flow into the facility. Because limited data are available to characterize the properties of dynamically compacted crushed salt, Sandia National Laboratories authorized RE/SPEC to perform additional tests on specimens of dynamically compacted crushed salt. These included shear consolidation creep, permeability, and constant strain-rate triaxial compression tests. A limited number of samples obtained from the large compacted mass were available for use in the testing program. Thus, additional tests were performed on samples that were prepared on a smaller scale device in the RE/SPEC laboratory using a dynamic-compaction procedure based on the full-scale construction technique. The laboratory results were expected to (1) illuminate the phenomenology of crushed-salt deformation behavior and (2) add test results to a small preexisting database for purposes of estimating parameters in a crushed-salt constitutive model. The candidate constitutive model for dynamically compacted crushed salt was refined in parallel with this laboratory testing.
Date: February 1, 1999
Creator: Hansen, F.D.; Mellegard, K.D. & Pfeifle, T.W.
Partner: UNT Libraries Government Documents Department

Theoretical model of granular compaction

Description: Experimental studies show that the density of a vibrated granular material evolves from a low density initial state into a higher density final steady state. The relaxation towards the final density follows an inverse logarithmic law. As the system approaches its final state, a growing number of beads have to be rearranged to enable a local density increase. A free volume argument shows that this number grows as N = {rho}/(1 {minus} {rho}). The time scale associated with such events increases exponentially e{sup {minus}N}, and as a result a logarithmically slow approach to the final state is found {rho} {infinity} {minus}{rho}(t) {approx_equal} 1/lnt.
Date: November 1, 1997
Creator: Ben-Naim, E.; Knight, J.B.; Nowak, E.R.; Jaeger, H.M. & Nagel, S.R.
Partner: UNT Libraries Government Documents Department

Compacting Plastic-Bonded Explosive Molding Powders to Dense Solids

Description: Dense solid high explosives are made by compacting plastic-bonded explosive molding powders with high pressures and temperatures for extended periods of time. The density is influenced by manufacturing processes of the powders, compaction temperature, the magnitude of compaction pressure, pressure duration, and number of repeated applications of pressure. The internal density variation of compacted explosives depends on method of compaction and the material being compacted.
Date: April 15, 2005
Creator: Olinger, B.
Partner: UNT Libraries Government Documents Department

Dynamic compaction of tungsten carbide powder.

Description: The shock compaction behavior of a tungsten carbide powder was investigated using a new experimental design for gas-gun experiments. This design allows the Hugoniot properties to be measured with reasonably good accuracy despite the inherent difficulties involved with distended powders. The experiments also provide the first reshock state for the compacted powder. Experiments were conducted at impact velocities of 245, 500, and 711 m/s. A steady shock wave was observed for some of the sample thicknesses, but the remainder were attenuated due to release from the back of the impactor or the edge of the sample. The shock velocity for the powder was found to be quite low, and the propagating shock waves were seen to be very dispersive. The Hugoniot density for the 711 m/s experiment was close to ambient crystal density for tungsten carbide, indicating nearly complete compaction. When compared with quasi-static compaction results for the same material, the dynamic compaction data is seen to be significantly stiffer for the regime over which they overlap. Based on these initial results, recommendations are made for improving the experimental technique and for future work to improve our understanding of powder compaction.
Date: April 1, 2005
Creator: Gluth, Jeffrey Weston; Hall, Clint Allen; Vogler, Tracy John & Grady, Dennis Edward
Partner: UNT Libraries Government Documents Department

The Influence of Lubrication on the Compactability of Magnesium-Green Salt Blends for Bomb Reduction

Description: Lubrication of die surfaces with mineral oil or Dag 217 during final compacting of UF/sub 4/--Mg blends prevented seizing. Mineral oil application after every third press allowed 18 compacts before seizing became severe. Similar application of Dag 217 allowed 78 compacts. Mixing 0.33 wt.% Ceremul "C" with the powder allowed 40 compacts. Punch clearance had little effect on seizing. (T.R.H.)
Date: June 18, 1957
Creator: Paprocki, S. J.; Carlson, R. J. & Smith, E. G., Jr.
Partner: UNT Libraries Government Documents Department

Phased array compaction cell for measurement of the transversely isotropic elastic properties of compacting sediments

Description: Sediments undergoing compaction typically exhibit transversely isotropic (TI) elastic properties. We present a new experimental apparatus, the phased array compaction cell, for measuring the TI elastic properties of clay-rich sediments during compaction. This apparatus uses matched sets of P- and S-wave ultrasonic transducers located along the sides of the sample and an ultrasonic P-wave phased array source, together with a miniature P-wave receiver on the top and bottom ends of the sample. The phased array measurements are used to form plane P-waves that provide estimates of the phase velocities over a range of angles. From these measurements, the five TI elastic constants can be recovered as the sediment is compacted, without the need for sample unloading, recoring, or reorienting. This paper provides descriptions of the apparatus, the data processing, and an application demonstrating recovery of the evolving TI properties of a compacting marine sediment sample.
Date: December 15, 2010
Creator: Nihei, K.T.; Nakagawa, S.; Reverdy, F.; Meyer, L.R.; Duranti, L. & Ball, G.
Partner: UNT Libraries Government Documents Department

Coal log pipeline research at University of Missouri. 3rd quarterly report for 1995, July 1, 1995--September 30, 1995

Description: During this quarter (1/1/95-9/30/95), major progress has been made in the following areas of coal log pipeline research, development and technology transfer: (1) Conceptual design of a test machine based on hydraulic presses to mass-produce 5.4-inch-diameter coal logs for testing in a 6-inch-diameter pipeline has been completed. (2) Conceptual design of a rotary-press machine to produce 1.9-inch-diameter coal logs for testing in a 2-inch-diameter pipeline has also been completed. (3) It has been confirmed through experiments that molds with round-edge exit can make logs as good as those made with tapered exit. (4) Conducted a study to determine the effect of surface condition of mold and lubricants on the quality of coal logs. (5) Completed an evaluation of the effect of fiber (wood pulp) on coal log quality. (6) Prepared an apparatus for testing fast compaction of coal logs -- 2 second per log. (7) Compacted coal logs in a 5.3-inch-diameter mold. (8) Completed a preliminary study to assess vacuum and steam heating systems to enhance coal log production and quality. (9) Changed the small-scale-CLP-demo loop from a once-through system to a recirculating system. (10) Completed revision of CLP economic model and revised the 1993 report.
Date: December 31, 1995
Creator: Liu, H.
Partner: UNT Libraries Government Documents Department

Tank farms compacted low-level waste

Description: This report describes the process of Low-Level Waste (LLW) volume reduction by compaction. Also included is the data used for characterization of LLW destined for compaction. Scaling factors (ratios) are formed based on data contained in this report.
Date: August 1, 1997
Creator: Hetzer, D. C.
Partner: UNT Libraries Government Documents Department

Shock wave structure in heterogeneous reactive media

Description: Continuum mixture theory and mesoscale modeling are applied to describe the behavior of shock-loaded heterogeneous media. One-dimensional simulations of gas-gun experiments demonstrate that the wave features are well described by mixture theory, including reflected wave behavior and conditions where significant reaction is initiated. Detailed wave fields are resolved in numerical simulations of impact on a lattice of discrete explosive {open_quotes}crystals{close_quotes}. It is shown that rapid distortion first occurs at material contact points; the nature of the dispersive fields includes large amplitude fluctuations of stress over several particle pathlengths. Localization of energy causes {open_quotes}hot-spots{close_quotes} due to shock focusing and plastic work as material flows into interstitial regions.
Date: June 1, 1997
Creator: Baer, M.R.
Partner: UNT Libraries Government Documents Department

Ceramic powder compaction

Description: With the objective of developing a predictive model for ceramic powder compaction we have investigated methods for characterizing density gradients in ceramic powder compacts, reviewed and compared existing compaction models, conducted compaction experiments on a spray dried alumina powder, and conducted mechanical tests and compaction experiments on model granular materials. Die filling and particle packing, and the behavior of individual granules play an important role in determining compaction behavior and should be incorporated into realistic compaction models. These results support the use of discrete element modeling techniques and statistical mechanics principals to develop a comprehensive model for compaction, something that should be achievable with computers with parallel processing capabilities.
Date: December 31, 1995
Creator: Glass, S.J.; Ewsuk, K.G. & Mahoney, F.M.
Partner: UNT Libraries Government Documents Department

The influence of crushed rock salt particle gradation on compaction

Description: This paper presents results of laboratory compaction testing to determine the influence of particle size, size gradation and moisture-content on compaction of crushed rock salt. Included is a theoretical analysis of the optimum size gradation. The objective is to evaluate the relative densities that can be achieved with tamping techniques. Initial results indicate that compaction increases with maximum particle size and compaction energy, and varies significantly with article size gradation and water content.
Date: December 31, 1994
Creator: Ran, C. & Daemen, J.J.K.
Partner: UNT Libraries Government Documents Department

Reaction of preshocked explosives

Description: In experiments in which an explosive is subjected to two successive shocks ({approximately}2.5 and {approximately}6.0 GPa), detonation of the explosive is delayed. High compaction resulting from shock compression of an explosive probably results in the removal of voids from the material. To the extent that these voids comprise the hotspots in the material, the shock-compressed explosive might be expected to behave as a homogeneous material, and initiate more like a liquid explosive than like a normal solid PBX. While some evidence is available from the data record to support this idea that detonation develops in a homogeneous manner, predominant aspects of the data indicate heterogeneous development of detonation in the preshocked material.
Date: July 31, 1998
Creator: Mulford, R.N.
Partner: UNT Libraries Government Documents Department