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Physical simulations of cavity closure in a creeping material

Description: The finite element method has been used extensively to predict the creep closure of underground petroleum storage cavities in rock salt. Even though the numerical modeling requires many simplifying assumptions, the predictions have generally correlated with field data from instrumented wellheads, however, the field data are rather limited. To gain an insight into the behavior of three-dimensional arrays of cavities and to obtain a larger data base for the verification of analytical simulations … more
Date: September 1, 1985
Creator: Sutherland, H.J. & Preece, D.S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Structural analysis of the West Hackbery No. 6 SPR storage cavern

Description: Four separate structural analyses of the West Hackberry No. 6 SPR storage cavern are presented. One analysis covers the creep response of the cavern beginning shortly before the time when an accidental fire occurred and proceeding through the cavern recertification pressure test. The second analysis models the surface uplife that is expected during the same pressure test. The third and fourth numerical studies investigate the structural response of West Hackberry No. 6 to slabbing and a rapid p… more
Date: August 1, 1980
Creator: Benzley, S.E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Boundary element formulation for planar time-dependent inelastic deformation of plates with cutouts

Description: A boundary element formulation for planar, time-dependent, inelastic deformation problems for bodies with cutouts is presented in this paper. A stress function description for these nonlinear problems leads to a nonhomogeneous biharmonic equation for the stress function rate. An integral representation of the solution uses modified kernels which guarantee that the cutout boundary is traction free for all time. This incorporation of the effect of the cutout on the stress field into the kernels l… more
Date: February 1, 1980
Creator: Mukherjee, S. & Morjaria, M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Development of an extended-burnup Mark B design. First semi-annual progress report, July-December 1978. Report BAW-1532-1. [PWR]

Description: The primary objective of this program is to develop and demonstrate an improved PWR fuel assembly design capable of batch average burnups of 45,000-50,000 MWd/mtU. To accomplish this, a number of technical areas must be investigated to verify acceptable extended-burnup fuel performance. This report is the first semi-annual progress report for the program, and it describes work performed during the July-December 1978 time period. Efforts during this period included the definition of a preliminar… more
Date: October 1, 1979
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Low strain diameter expansion of internally pressurized Zircaloy-4 tubing at high temperatures

Description: Tests of closed-end, internally pressurized, Zircaloy-4 tubing specimens were utilized to develop low strain creep characteristics as a function of time at temperatures in the range of 1475/sup 0/F to 2000/sup 0/F (802/sup 0/C to 1093/sup 0/C) and hoop stresses in the range of 250 to 2500 psi for use in loss-of-coolant accident (LOCA) analyses. The strain rate above the start of the alpha to beta phase transformation region, approximately 1490/sup 0/F (810/sup 0/C), was found to be sensitive to… more
Date: March 1978
Creator: White, L.S. & Busby, C.C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Creep of whisker-reinforced ceramics

Description: The results of high-temperature creep of various ceramic composites will be reviewed. In particular, creep results for Al{sub 2}O{sub 3} and Si{sub 3}N{sub 4} matrices reinforced with SiC whiskers will be emphasized. For a given temperature, stress and grain size, the creep rate of the Al{sub 2}O{sub 3} composite is usually lower than that of the ceramic matrix. In general, creep at low stresses occurs by grain boundary sliding accommodated by diffusion, whereas higher stresses lead to damage a… more
Date: January 1, 1991
Creator: Routbort, J.L; Goretta, K.C. (Argonne National Lab., IL (United States)); Dominguez-Rodriguez, A. & de Arellano-Lopez, A.R. (Seville Univ. (Spain))
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Advanced Gas Cooled Nuclear Reactor Materials Evaluation and Development Program. Progress report, January 1, 1980-March 31, 1980

Description: Results are presented of work performed on the Advanced Gas-Cooled Nuclear Reactor Materials Evaluation and Development Program. The objectives of this program are to evaluate candidate alloys for Very High Temperature Reactor (VHTR) Nuclear Process Heat (NPH) and Direct Cycle Helium Turbine (DCHT) applications, in terms of the effect of simulated reactor primary coolant (helium containing small amounts of various other gases), high temperatures, and long time exposures, on the mechanical prope… more
Date: June 25, 1980
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Boundary element analysis of time-dependent inelastic deformation of cracked plates loaded in anti-plane shear

Description: A boundary element analysis, for determining stresses in planar cracked bodies undergoing Mode I or Mode II inelastic deformation, has been recently published by the present authors. One primary advantage of this formulation is that the effect of the crack is incorporated in the kernels of the integral equations. Thus, traction free conditions on the crack boundary are satisfied without discretization of this boundary in a numerical calculation procedure. The inelastic deformation of cracked pl… more
Date: July 1, 1980
Creator: Mukherjee, S. & Morjaria, M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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MHD air heater development technology. Progress report, November 26, 1979-March 31, 1980

Description: Work on the development of the directly-fired high temperature air heater (HTAH) for MHD power plants is reported. Progress is reported on three tasks: (1) materials selection, evaluation, and development, (2) operability, performance, and materials testing, and (3) full-scale design concepts. Under Task 1, efforts were carried out in several areas. Work on the computer data base for material properties was begun. Data were compiled for several HTAH materials. Materials selections for Valve Tes… more
Date: May 1, 1980
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Quality-assurance study of the special - purpose finite-element program - SPECTROM: I. Thermal, thermoelastic, and viscoelastic problems. [Comparison with MARC-CDC]

Description: This comparison study involves a preliminary verification of finite element calculations. The methodology of the comparison study consists of solving four example problems with both the SPECTROM finite element program and the MARC-CDC general purpose finite element program. The results show close agreement for all example problems.
Date: December 1, 1980
Creator: Wagner, R. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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MHD power generation research, development and engineering. Quarterly progress report, October-December 1979

Description: Progress is reported on the following tasks: characterization of coal for open-cycle MHD power generation systems; compressive creep and strength studies of MHD preheater materials; preparation of coals for utilization in direct coal-fired MHD generation; characterization of volatile matter in coal; MHD materials evaluation; operability of the Moderate Temperature Slag Flow Facility; slag-seed equilibria and separations related to the MHD system; thermionic emission of coal and electrode materi… more
Date: January 1, 1979
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Time-dependent behavior of concrete

Description: This paper is a condensed version of the material presented at the International Workshop on Finite Element Analysis of Reinforced Concrete, Session 4 -- Time Dependent Behavior, held at Columbia University, New York on June 3--6, 1991. Dr. P.A. Pfeiffer presented recent developments in time-dependent behavior of concrete and Professor T. Tanabe presented a review of research in Japan on time-dependent behavior of concrete. The paper discusses the recent research of time-dependent behavior of c… more
Date: January 1, 1992
Creator: Pfeiffer, P.A. (Argonne National Lab., IL (United States)) & Tanabe, Tada-aki (Nagoya Univ. (Japan). Dept. of Civil Engineering)
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Frank loop unfaulting mechanism in fcc metals during neutron irradiation

Description: The unfaulting mechanism whereby sessile Frank dislocation loops evolve into a complex tangle of glissile dislocations during irradiation of face centered cubic metals is not well understood. It is presumed that such loops grow by absorption of point defects until interactions develop which provide sufficient impetus for nucleation of an unfaulting event. The loops then become glissile, interact and form a dislocation network. An alternate mechanism which has been observed to occur in an austen… more
Date: May 1980
Creator: Gelles, D. S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Engineering data bases for refractory alloys

Description: Refractory alloys based on niobium, molybdenum, tantalum, and tungsten are required for the multi-100kW(e) space nuclear reactor power concepts that have been assessed in the SP-100 Program because of the extremely high temperatures involved. A review is presented of the technology efforts on the candidate refractory alloys in the areas of availability/fabricability, mechanical properties, irradiation effects, and compatibility. Of the niobium-base alloys, only Nb-1Zr has a data base that is su… more
Date: January 1, 1985
Creator: Cooper, R.H. Jr. & Harms, W.O.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Analysis of anelastic relaxations controlled by a spectrum of relaxation times

Description: Anelastic studies, although they have provided an important method for investigating the mobility of point defects in solids, have often been difficult to analyze when a continuous spectra of relaxation times controls the anelastic response. This paper describes a new method for obtaining accurate estimates of relaxation time spectra by direct analysis (without prior assumptions) of the data using a nonlinear regression method. Applications to internal friction and anelastic creep results are d… more
Date: January 1, 1983
Creator: Cost, J.R.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Cladding creepdown under compression. [BWR; PWR]

Description: Light-water power reactors use Zircaloy tubing as cladding to contain the UO/sub 2/ fuel pellets. In-service operating conditions impose an external hydrostatic force on the cladding, causing it to creep down into eventual contact with the fuel. Knowledge of the rate of such creepdown is of great importance to modelers of fuel element performance. An experimental system was devised for studying creepdown that meets several severe requirements by providing (1) correct stress state, (2) multiple … more
Date: November 9, 1977
Creator: Hobson, D.O.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Heated mine room and pillar secondary creep response

Description: Heated salt mine room and pillar simulations have been performed to provide information regarding parameters affecting room closure rates to designers of radioactive waste isolation facilities. A coupled secondary creep and heat transfer formulation with large strain capabilities was used to assess the effects of variations in creep law parameters, thermal properties, imposed boundary conditions, temporal integration, and meshing resolution on room closure rates. Results indicate that the great… more
Date: April 1, 1980
Creator: Tillerson, J.R. & Dawson, P.R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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A perspective on MoSi sub 2 based composites

Description: MoSi{sub 2} based composites represent an important new class of high temperature structural silicides,'' with significant potential for elevated temperature structural applications in the range of 1200--1600{degrees}C in oxidizing and aggressive environments. The properties of MoSi{sub 2} which make it an attractive matrix for high temperature composites are described and the development history of these materials traced. Latest results on elevated temperature creep resistance, low temperature… more
Date: January 1, 1992
Creator: Petrovic, J.J. (Los Alamos National Lab., NM (United States)) & Vasudevan, A.K. (Office of Naval Research, Arlington, VA (United States))
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Thermal stress and creep fatigue limitations in first wall design

Description: The thermal-hydraulic performance of a lithium cooled cylindrical first wall module has been analyzed as a function of the incident neutron wall loading. Three criteria were established for the purpose of defining the maximum wall loading allowable for modules constructed of Type 316 stainless steel and a vanadium alloy. Of the three, the maximum structural temperature criterion of 750/sup 0/C for vanadium resulted in the limiting wall loading value of 7 MW/m/sup 2/. The second criterion limite… more
Date: January 1, 1977
Creator: Majumdar, S.; Misra, B. & Harkness, S.D.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Some safety considerations in the selection of redans for pool-type LMR plants

Description: Three basic safety issues in the selection of the redan design for a pool type liquid metal fast breeder reactor plant are examined. The first area examined is the effect of the redan selection on the integrity of the primary system pressure boundary in normal and offset conditions. The second area is on the consequence of the hypothetical core disruptive accident. The third area is on the consequence of the loss of heat sink accident. Some general discussion and numerical results are presented… more
Date: January 1, 1985
Creator: Pan, Y. C.; Pedersen, D. R. & Wang, C. Y.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Effects of chemical and gamma irradiation environments on the mechanical properties of high-density polyethylene (HDPE)

Description: High-density polyethylene (HDPE) is currently being used as a high-integrity container material for low-level wastes. Potential failure/degration modes must be determined for realistic environmental conditions. These include consideration of mechanical stress, gaseous/liquid environments within and external to the container, and the gamma radiation field. A combination of simple inexpensive tests (stressed U-bend samples) and more sophisticated longer-term uniaxial creep tests are being used to… more
Date: January 1, 1988
Creator: Soo, P.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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In-sodium creep behavior of alloys M-813 and Nimonic PE16

Description: The in-sodium biaxial creep deformation of internally pressurized tube specimens of alloys M-813 and Nimonic PE16 was measured at 650/sup 0/C under constant stress conditions after 4000 hours of sodium exposure. Each alloy had specimens at two different stress levels, viz., 0 and 165 MPa (24,000 psi). The data showed negative diameter changes at zero stress, which were attributed to material densification associated with precipitation. Although material densification was also seen in comparable… more
Date: April 1, 1980
Creator: Anantatmula, R.P. & Gilbert, E.R.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Procedure to evaluate structural adequacy of a piping system in creep range

Description: An inelastic analysis procedure to establish structural adequacy of an elevated temperature piping system is presented in this paper. The analytical method is incidental to the procedure used to comply with Code Case N-47 inelastic strain accumulation and creep-fatigue damage criteria.
Date: January 1, 1982
Creator: Dhalla, A. K.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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