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in subjects: "Strains"

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Assessment of light water reactor fuel damage during a reactivity initiated accident

This paper presents an assessment of LWR fuel damage during a reactivity initiated accident and comments on the adequacy of the present USNRC design requirements. Results from early SPERT tests are reviewed and compared with results from recent computer simulations and PBF tests. A progression of fuel rod and cladding damage events is presented. High strain rate deformation of relatively cool irradiated cladding early in the transient may result in fracture at a radial average peak fuel enthalp… more

Date: January 1, 1980

Creator: MacDonald, P. E.; Seiffert, S. L.; Martinson, Z. R.; McCardell, R. K.; Owen, D. E. & Fukuda, S. K.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Low strain diameter expansion of internally pressurized Zircaloy-4 tubing at high temperatures

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: Report

Partner: UNT Libraries Government Documents Department

open access

Inelastic processes in seismic wave generation by underground explosions

Theories, computer calculations, and measurements of spherical stress waves from explosions are described and compared, with emphasis on the transition from inelastic to almost-elastic relations between stress and strain. Two aspects of nonspherical explosion geometry are considered: tectonic strain release and surface spall. Tectonic strain release affects the generation of surface waves; spall closure may also. The reduced-displacement potential is a common solution (the equivalent elastic so… more

Date: August 1, 1980

Creator: Rodean, H.C.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Solder fatigue reduction in point focus photovoltaic concentrator modules

Solder fatigue tests have been conducted on point focus photovoltaic concentration cell assemblies to identify a baseline fatigue life and to quantify the fatigue life improvements that result using a copper-molybdenum-copper low-expansion insert between the solar cell and copper heat spreader. Solder microstructural changes and fatigue crack growth were identified using cross sections and ultrasonic scans of the fatigue solder joints. The Coffin-Manson and Total Strain fatigue models for low-c… more

Date: January 1, 1991

Creator: Hund, T. D. & Burchett, S. N.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

CHILES 2: a finite element computer program that calculates the intensities of linear elastic singularities in isotropic and orthotropic materials

CHILES 2 is a finite-element computer program that calculates the strength of singularities in linear elastic bodies. A generalized quadrilateral finite element that includes a singular point at a corner node is incorporated in the code. The displacement formulation is used and interelement compatibility is maintained so that monotone convergence is preserved. Plane stress, plane strain, and axisymmetric conditions are treated. Isotropic and orthotropic crack tip singularity problems are solved… more

Date: February 1, 1978

Creator: Benzley, S.E. & Beisinger, Z.E.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Development of superconductors for applications in high-field, high-current-density magnets for fusion research

The development of large-bore, high-field magnets for fusion energy applications requires a system approach to both magnet and conductor design. At Lawrence Livermore National Laboratory (LLNL), the criteria used to choose superconductors include: strain tolerance, radiation tolerance, heat removal, stability, fabricability, and cost. We report on the performance of industrially produced, prototype, Ti-modified Nb/sub 3/Sn wires developed with LLNL support. Wire performance characteristics eval… more

Date: September 26, 1986

Creator: Summers, L. T. & Miller, J. R.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Geotechnical Properties of Sediments From North Pacific and Northern Bermuda Rise

Studies of geotechnical properties for the Sub-seabed Disposal Program have been oriented toward sediment characterization related to effectiveness as a containment media and determination of detailed engineering behavior. Consolidation tests of the deeper samples in the North Pacific clays indicate that the sediment column is normally consolidated. The in-situ coefficient of permeability (k) within the cored depth of 25 meters is relatively constant at 10/sup -7/ cm/sec. Consolidated undrained… more

Date: January 1, 1980

Creator: Silva, A. J.; Laine, E. P.; Lipkin, J.; Heath, G. R. & Akers, S. A.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Postirradiation cladding strength under biaxial loading with an increasing temperature ramp. [LMFBR]

The flow behavior of unirradiated 20% cold worked AISI 316 tubing during constant pressure, increasing temperature tests was modeled with a constitutive relation approach; strain below approximately 0.2% came predominantly from an anelastic portion of the model while higher strains were predominantly plastic. The flow of cladding sections from irradiated fuel pins was largely restricted to the strain region attributed to anelastic deformation due to reduced ductility compared to unirradiated tu… more

Date: April 1, 1980

Creator: Duncan, D. R. & Hunter, C. W.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Conduction- and valence-band dispersion curves: III-V semiconductor quantum wells

No Description Available.

Date: January 1, 1991

Creator: Jones, E. D.; Lyo, S. K. & Klem, J. F.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Time-dependent behavior of concrete

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: Article

Partner: UNT Libraries Government Documents Department

open access

Development of the freely expanding ring test for measuring dynamic material properties

Modifications to the freely expanding ring test for eliminating adverse two-dimensional effects are described and illustrated. The result is to substantially increase the strain-rate range over which dynamic material property data can be reliably obtained. Several different ring launching schemes are discussed, and data are presented that were taken with a particular shockless electromagnetic system. Results from initial attempts at measuring dynamic compressive properties with a contracting ri… more

Date: January 1, 1982

Creator: Warnes, R. H.; Karpp, R. R.; Duffey, T. A.; Carden, A. E. & Jacobson, J. D.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Materials for coal gasification. Effect of environment on stress rupture

The biaxial stress rupture behavior for two of the alloys, Type 310 stainless steel and Haynes 188, is shown in figures. The other two alloys show similar behavior. The rupture parameter, P, is an empirical quantity which reflects the simultaneous effects of both temperature and duration of applied stress on stress rupture. Based on these results, several trends are apparent: (1) the biaxial stress rupture tests show the same trends and approximately the same stress rupture values as uniaxial d… more

Date: January 1, 1980

Creator: Horton, R.M.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Work hardening correlation for monotonic loading based on state variables

An absolute work hardening correlation in terms of the hardness parameter and the internal stress based on the state variable approach was developed. It was found applicable to a variety of metals and alloys. This correlation predicts strain rate insensitive work hardening properties at low homologous temperatures and produces strain rate effects at higher homologous temperatures without involving thermally induced recovery processes.

Date: January 1, 1977

Creator: Huang, F. H. & Li, C. Y.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Microscopic determination of stress distribution in GaAs grown at low temperature on GaAs (100)

A microscopic strain distribution across commensurate interfaces between GaAs layers grown on semi-insulating GaAs substrates was observed by means of convergent beam electron diffraction (CBED) and large angle convergent beam methods (LACBED). Strain relaxation at a specific distance from the interface was observed in these layers without formation of misfit dislocations. It was proposed that specific point defects distributed close to the interface can explain the asymmetric broadening of hig… more

Date: January 1991

Creator: Liliental-Weber, Z.; Tanaka, M.; Ishikawa, A. & Teriauchi, M.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Interconnect fatigue design for terrestrial photovoltaic modules

Fatigue of solar cell electrical interconnects due to thermal cycling has historically been a major failure mechanism in photovoltaic arrays; the results of a comprehensive investigation of interconnect fatigue that has led to the definition of useful reliability-design and life-prediction algorithms are presented. Experimental data gathered in this study indicate that the classical strain-cycle (fatigue) curve for the interconnect material is a good model of mean interconnect fatigue performan… more

Date: March 1, 1982

Creator: Mon, G. R.; Moore, D. M. & Ross, R. G., Jr.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Development of sheet molding compound solar collectors with molded-in silvered glass reflective surfaces

An approach to the fabrication of a line-focusng parabolic trough reflector structure which offers the potential of high performance while utilizing mass production type technology with potential for low cost is discussed. The concept is one of a molded structure of fiber reinforced plastic with an integrally molded silvered glass reflective surface. Sheet molding compound (SMC), a mixture of glass fibers and inorganic fillers in polyester resin, has been selected for evaluation as representati… more

Date: January 1, 1980

Creator: Champion, R. L. & Allred, R. E.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Strain distribution and model for formation of eastern Umtanum Ridge anticline, south-central Washington

Umtanum Ridge in south-central Washington is the topographic expression of a complex anticline within the Yakima Fold system in the Miocene Columbia River Basalt Group. The Yakima Fold system, which is partly contained within the Hanford Site, is an example of a layered basalt sequence folded near the surface of the earth. The Pasco Basin stratigraphic nomenclature is used in this repot. Rockwelll Hanford Operations, under contract to the US Department of Energy, is investigating the feasibilit… more

Date: October 1, 1979

Creator: Price, E.H.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Physical processes of compaction companion report 1 to simulation of geothermal subsidence

There are a variety of theories, techniques, and parameters in the subsidence literature. Biot's theory, Terzaghi's theory, and the theory of interacting continua (TINC) are used to explain solid-fluid interaction; stress-strain theories range from linear elastic to e-log p to plasticity and pore-collapse theories. Parameters are numerous: void ratio,, permeability, compaction coefficient, pore compressibility, Young's modulus, bulk modulus, shear modulus, Poisson's ratio, Lame coefficients, co… more

Date: March 1, 1980

Creator: Miller, I.; Dershowitz, W.; Jones, K.; Myer, L.; Roman, K. & Schauer, M.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Studies of the strain-dependent properties of A15 filamentary conductors at Brookhaven National Laboratory

Work at BNL pertaining to the strain response of filamentary bronze-processed superconductors is reviewed. This work includes the intrinsic strain dependence of the critical properties of A15 structure compounds, the nature of the initial internal strain state of composite conductors, and the interplay between these residual strains and applied strains which governs the response of the conductor to external strain. Some factors which can enhance the strain tolerances of filamentary conductors a… more

Date: January 1, 1980

Creator: Luhman, T & Welch, D O

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Investigation of the cryogenic mechanical properties of low thermal-expansion superalloys

Four Fe-based superalloys, JBK-75, Incoloy 903, Incoloy 905, and Incoloy 909 were evaluated as tube materials for ICCS Nb/sub 3/Sn superconductors. Evaluation consisted of 4-K tensile and elastic-plastic fracture-toughness testing, and a microstructural characterization of unwelded and autogenously gas-tungsten-arc welded sheet given a simulated postweld processing treatment of 15% cold reduction by rolling followed by a Nb/sub 3/Sn-reaction heat treatment of 96 hours at 700/sup 0/C plus 48 hou… more

Date: July 30, 1985

Creator: Summers, L.T. & Dalder, E.N.C.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Effects of cyclic strains on transport properties of a superconducting composite: phase I, degradation of electrical conductivity in copper at 4. 2 K

Aspects of superconducting composites for magnetic fusion applications are discussed.

Date: August 1, 1977

Creator: Fisher, E. S.; Kim, S. H.; Linz, R. J. & Turner, A. P. L.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Dynamic rock fragmentation: oil shale applications

Explosive rock fragmentation techniques used in many resource recovery operations have in the past relied heavily upon traditions of field experience for their design. As these resources, notably energy resources, become less accessible, it becomes increasingly important that fragmentation techniques be optimized and that methods be developed to effectively evaluate new or modified explosive deployment schemes. Computational procedures have significant potential in these areas, but practical ap… more

Date: January 1, 1980

Creator: Boade, R. R.; Grady, D. E. & Kipp, M. E.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Numerical simulation of plasticity at high strain rate

In numerical simulations of solid dynamics, the total strain rates are calculated from the velocity fields and are input to the constitutive laws. For an elastic-plastic material, the strain rate for a computational cycle may cause the elastic stress to exceed the specified yield surface. This implies that the stress path must move along the yield surface, and some of the strain is realized as plastic (irreversible) strain. The usual numerical method of integrating the elastic-plastic stress-st… more

Date: January 1, 1991

Creator: Margolin, L. (Los Alamos National Lab., NM (USA)) & Flower, E.C. (Lawrence Livermore National Lab., CA (USA))

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Analysis of the ballooning deformation of an internally pressurized thin-wall tube during fast thermal transients

A large-strain time-dependent thermoplastic analysis has been developed for the ballooning deformation of a thin-wall tube subjected to internal pressure, axial loading, and fast thermal transients. This deformation initiates with the onset of plastic instability in the material, the onset being determined by a plastic-instability criterion for strain-rate sensitive materials. The interaction among the local ballooning geometry, the state of stress, and the plastic flow process was considered, … more

Date: January 1, 1977

Creator: Lin, E.I.H.

Item Type: Article

Partner: UNT Libraries Government Documents Department