bluuebunny/crossref_metadata_2025_split huggingface dataset:
Shear Strength of Sand at Constant Volume
Authors: Sadasivan SK , Raju VS 
Published: February 2009

Abstract
To verify the expressions developed by other researchers for separating the strength component resulting from volume change in shear (dilatancy), shear tests at constant volume as well as drained tests are necessary. In conventional undrained triaxial tests on granular materials, volume change of the soil skeleton occurs as a result of rubber membrane penetration. In the present investigation, conventional tests were modified to ensure a constant volume condition by compensating for the rubber membrane penetration.
Drained tests, conventional undrained tests, and modified undrained tests were conducted on a uniform medium sand, uniform coarse sand, and a gap-graded sand; the results are compared. Conventional undrained tests gave somewhat higher values of shear strength than those of modified undrained tests. The results of drained tests corrected for volume change compare well with those of modified undrained tests.
Scale and Corrosion Parameters at a Geothermal Loop Experimental Facility
Authors: Jacobson WO , Rogers AN , Schoepflin F , Henry PM 
Published: February 2009

Abstract
Metallic alloys and nonmetallic materials, including coatings and plastic liners, were exposed to high-temperature (232.2°C [450°F]), highly saline (20%) brines in a 10-MW geothermal loop experimental facility at the Salton Sea Known Geothermal Resource Area in the Imperial Valley, Calif. Mild carbon steel corrodes rapidly, especially in presence of air, while nickel alloys are very resistant to the Salton Sea geothermal brines. The Teflon® coatings and the vinyl esters exhibited the greatest resistance among the nonmetallic materials tested. Twenty-seven proprietary scale inhibitors were tested to determine the ones most promising for use in the Salton Sea brines. Several scale control additives were effective in retarding silica precipitation at 90°C, the temperature limit of these laboratory tests.
Comparison of Methods for Fracture Toughness Determination in Steels
Authors: Cobanoglu MM , Kardos G 
Published: February 2009

AbstractThis study compares various test methods and estimation procedures that are available for determining the fracture toughness of steels. The ASTM Test for Plane-Strain Fracture Toughness of Metallic Materials (E 399), the energy rate test, and the multiple identical specimen crack growth resistance R curve test for elastic-plastic fracture toughness JIc determination are compared. Various formulations for plane-strain fracture toughness KIc and JIc estimation are also compared. Comparison of the test methods indicates that, for ductile steels, the multiple identical specimen R curve test is the most promising. It is suggested that the total areas be used for calculation of J from Rice's approximate formulation for three-point bend specimens of ductile steels and crack-contributed areas for brittle steel three-point bend specimens.
On the Relationship of Toughness, Fracture Initiation Energy, and Specimen Deflection in Charpy Tests of 4340 Steel
Authors: Datta KP , Wood WE 
Published: February 2009

AbstractThe toughness of quenched 4340 steel (American Iron and Steel Institute designation) has been studied as a function of notch root radius and tempering temperature for several testing conditions (such as room temperature slow-bend Charpy, room temperature instrumented Charpy). The toughness, the square root of the fracture initiation energy, and the specimen deflection at fracture initiation follow similar trends under identical conditions in each type of testing. Thus fracture initiation energy and the specimen deflection in Charpy testing can be measures of toughness. These three macroscopic relationships are independent of fracture morphology, grain size, or plastic zone size. Theoretical relationships among the three are proposed.
Simplified Equations for Peak Position and for Its Standard Deviation in X-Ray Stress Measurement
Authors: Kurita M 
Published: February 2009

Abstract
Simplified equations for peak position and for its standard deviation resulting from counting statistics are derived in the n points parabola method. These equations are applicable to an even as well as an odd n and can be rapidly calculated even with an inexpensive on-line computer such as a microcomputer. Thus a rapid and precise peak determination can be made by use of these equations with an inexpensive X-ray stress measurement system. Various peak positions calculated by the n points and the three points parabola methods were compared. Two heat-treated steels were used. The n points method, using all the data points that fall above approximately 85% of the maximum intensity, gave the most satisfactory result. On the other hand, the three points method produced a large standard deviation of the peak position unless the three points were taken symmetrically about the diffraction peak.
Some Aspects of Biaxial Creep Testing of Thin-Walled Cylindrical and Spherical Pressure Vessels
Authors: Arbel A , Eliezer D 
Published: February 2009

Abstract
Expressions are derived for the expansion of cylindrical and spherical pressure vessels that creep at a constant temperature while being internally pressurized by a constant amount of an ideally behaving gas. The main portion of the initial volume of the pressure vessels is occupied by a rod or a ball-type insert to reduce the energy released or containment requirement if a rupture should occur.
Task Group Report: Results of Interlaboratory Test Programs to Evaluate the Dynamic Tear Test Method
Authors: Lazaridis NA , Heberling TG , Harris ES , Lange EA 
Published: February 2009

Abstract
An ASTM Task Group evaluated the revised Standard Test Method for Dynamic Tear Energy of Metallic Materials (E 604). The revised method expanded the range of specimen thickness from the 16 mm (⅝ in.) specified in E 604-77 to include specimens ranging from 4.8 to 16 mm (3/16 to ⅝ in.) in thickness. The minimum impact velocity was also changed from 4.9 to 4 m/s (16 to 13 ft/s). Three series of tests were conducted by 16 laboratories on steels of low, intermediate, and high yield strength. A total of 1300 specimens were involved over a two-year period, and the results were analyzed statistically to support the modifications in the dynamic tear test method. No variations of engineering significance in dynamic tear energy were found with respect to between-laboratory variation in procedures, testing machine type, impact velocity, and specimen preparation within the tolerances set for the dimensions of the test specimens and the critical parameters of the testing procedure.
A Torsion Pendulum for Measurement of Damping Capacity and Related Phenomena
Authors: James DW , Stott JD , Emery B 
Published: February 2009

Abstract
Investigation of the damping mechanisms of metals and alloys requires that damping capacity measurements be made over wide stress, frequency, and temperature ranges. The torsion pendulum described herein fulfills these requirements in all respects except that it has a limited (low) frequency range. This versatile apparatus also allows creep, fatigue, stress relaxation, elastic after-effect, static and dynamic moduli and hysteresis curves to be made at temperature and in vacuo. It is possible to superimpose a magnetic field on the specimen during these measurements. The specimen may also be heat treated or plastically deformed in situ. An electronic data processing system has been designed to calculate and plot material damping characteristics during a free decay test. The damping characteristics are thus obtained more quickly and with greater accuracy than was previously possible.
A Concept for Fatigue Analysis of Complex Components
Authors: Leis BN 
Published: February 2009

AbstractRecently, a two-step procedure that determines local stresses and strains as functions of loading and that assesses the fatigue damage they cause in terms of smooth specimen laboratory test data has shown promise in making consistently accurate life to crack initiation predictions of notched specimens. However, this procedure, which accounts for notch effects by using a single parameter, is less accurate in predicting the fatigue life for complex components than that for simple notched specimens. The present paper examines the problems of predicting the fatigue life of complex components and structures. It is shown that fatigue life in such structures is governed by the multiplicity of initiation locations and crack initiation mechanisms. An approach is outlined whereby the role of each potential initiation location and mechanism is accounted for in fatigue analysis of the structures by using the two-step procedure. Fatigue life predictions are made for a hypothetical complex component to illustrate the approach and its application. The accuracy of the approach is then assessed by comparing the results of actual test data for a built-up box beam with those simulated by using the approach outlined in this paper.
Structural Materials for Nuclear Power Plants
Authors: Bush SH 
Published: February 2009

AbstractCommercial ferritic and austenitic steels are the predominant materials used in both fossil and nuclear power plants; the significant difference in nuclear plants is the exposure to neutron fluence. Three aspects of material behavior are reviewed: (1) the role of residual elements on radiation damage of steels used for water reactor pressure vessels, (2) influence of neutron-gamma flux and water reactor coolant on stress corrosion, and (3) neutron-induced swelling and void formation in austenitic stainless steels in fast reactors.
Laser-Heating-Induced Failure of Metal Alloys Under Constant Stress
Authors: McLellan DL 
Published: February 2009

Abstract
The failure conditions of three structural materials have been investigated under a number of constant axial tensile stresses and rapid heating rates. Laser heating was used to produce failure by fracture for selected times between nominally 0.10 and 100 s. The three sheet gage materials tested were 2024-T81 (alclad), Ti-6Al-4V (mill annealed), and 301 stainless steel (hard). Properties determined in this manner are applicable to vulnerability analyses of aircraft and missile structures. Temperatures for 1-s failure times of constantly stressed parts are significantly higher than those which accompany both the static ultimate tensile strength and long-duration creep rupture behaviors.
Magnetomechanical Damping Properties of AISI 403 Stainless Steel with Applied Static Torsional and Axial Stresses
Authors: Willertz LE 
Published: February 2009

Abstract
The magnetomechanical damping properties of an AISI 403 stainless steel, tested in torsion, were found to behave differently under the action of applied static axial and torsional stresses. A constant torsional stress decreased the damping peak, broadened it, and shifted it to higher stresses. In contrast, a static axial load shifted the peak to lower log decrement values but did not change the peak damping stress. These observations are explained in terms of the effect of the static stresses on the shape of the stress-strain hysteresis loop.
Comparison of Static and Dynamic Mechanical Properties of Some Epoxy-Matrix Composites
Authors: Jenness JR , Kline DE 
Published: February 2009

Abstract
Static and dynamic elastic moduli in flexure were measured for a diglycidyl ether of bisphenol A cured with metaphenylenediamine and some particulate composites with this polymer as the matrix. If it is assumed that these materials have tensile moduli which are about 0.925 of their compressive moduli, as has been noted for another epoxy system, dynamic moduli determined at very low strain values by a free-free flexural resonance technique appear to be very nearly equal to the tensile moduli in static flexure. However, little correlation was observed between the dynamic mechanical properties and other static properties such as flexural strength. This is partially attributed to the difference in stress patterns in the static and dynamic tests.
Procedures Used to Evaluate the Thermal Properties of Soils Adjacent to Buried Extra High Voltage Lines
Authors: Salomone LA , Fischer JA , Watson I 
Published: February 2009

Abstract
Because of the high voltages and operating temperatures now being considered for transmission lines from offshore generating stations, assessment of the thermal characteristics of the soils surrounding these cables is critical—both to avoid failure of the cables by overheating and to establish a practical engineering procedure to facilitate sound and economic cable designs in the future.
A tridirectional approach used in a case history study to establish values of thermal resistivity along proposed offshore and onshore cable alignments is described. The procedural format developed is considered to have useful general application to this type of problem. Soils studied included clean sands and silty sands, silts, clays, and organic material (peat).
The Application of the Single-Edge Notched Beam to Fracture Toughness Testing of Ceramics
Authors: Simpson LA , Hsu TR , Merrett G 
Published: February 2009

AbstractThere is a need for easy-to-fabricate fracture toughness specimens for ceramics. The single-edge notched beam satisfies this need, except that the American Society for Testing and Materials (ASTM) specification for notch root crack depth is difficult to achieve in ceramics using standard metallurgical methods. Finite element techniques are used to demonstrate that a minimum ratio of crack depth to notch root radius of 0.5 is sufficient for a valid test in a ceramic. These calculations are confirmed by experiments on soda-lime glass specimens.
A New Test for Sulfate Resistance of Cements
Authors: Mehta PK , Gjørv OE 
Published: February 2009

Abstract
Sulfate attack on concrete can either be of expansion-cracking type due to ettringite formation or of surface deterioration type due to acidic nature of sulfate solutions. The present test methods for determining sulfate resistance generally evaluate the expansive attack phenomenon. Since low C3A portland cements are not susceptible to this type of attack, new methods need to be developed to test the long-time resistance of these cements to the acidic type of sulfate attack. An attempt to develop a laboratory method involving immersion of small specimens of cement paste in a sulfate solution held at constant pH is described. Preliminary results are given for five different types of cements tested in accordance with the new method.
An Investigation of the Fluid Characteristics of Cement Grouts
Authors: Huang WH 
Published: February 2009

Abstract
A method for viscosity measurement of cement grouts is discussed in this paper and the results are presented in the form of formulas and curves.
The cement used in the tests was Type II portland cement. It was found that the cement grouts with water/cement ratios of 0.42 to 0.44 have fluid characteristics of Bingham plastic type.
The hydraulic grade line of grout in a tendon duct was estimated using laboratory viscosity data and was compared with a field test.
Computational Aids for Kinematic Viscosity Conversions from 100 to 210°F to 40 and 100°C
Authors: Manning RE 
Published: February 2009

Abstract
In the petroleum industry the standard temperatures of test are being changed from the traditional 100 and 210°F to 40 and 100°C. Graphs and tables are given which allow for easy, accurate calculation of kinematic viscosity at the new test temperatures from data at the former test temperatures.
The Calculation of Gas Transmission Rates Measured by Manometric Methods
Authors: Evans RE 
Published: February 2009

Abstract
It is shown that an error in the calculated gas transmission rate of greater than 20 percent can result when using the standard equation presented in Method M of the American Society for Testing and Materials Test for Gas Transmission Rate of Plastic Film and Sheeting [D 1434–66 (1972)]. The magnitude of this error is shown to be a function of both cell void volume and pressure. Therefore, disagreements in results calculated using different cells and operating conditions can be explained. The exact solution of the equation is presented together with an approximation; the latter facilitates calculations and results in an error of less than one percent.
Evaluation of Large Strains in Industrial Applications
Authors: Wolak J , Parks VJ 
Published: February 2009

Abstract
For the case of a two-dimensional strain field the usual concepts of direct and of shear strains are developed in terms of the principal strains and of the orientations of the elements in question. These expressions are used to form a Mohr's circle, which permits the transformation of strain from one axis of reference to another, irrespective of the magnitude of the strain, and leads to the evaluation of the principal strain components from the measurement of direct strain in three directions. A numerical example of application to the mechanics of metal cutting is given.
The paper may be of interest to metal-forming engineers and to specialists working in areas involving the analysis of large plastic strains.
Distinction Between Coaxial and Noncoaxial Strains in Sheet Metal and Its Implications on the Assessment of Material Formability
Authors: Hsü TC 
Published: February 2009

Abstract
The distinction between coaxial and noncoaxial strains is explained. It is shown that with noncoaxial strains deformation does not necessarily produce a change of shape, if circles and ellipses are used for strain measurements. If materials are tested in exisymmetrical processes, in which the strains are coaxial, and used in unsymmetrical ones, in which the strains are noncoaxial, then the formability will appear to be overestimated. A test for coaxiality, based on the use of squares and parallelograms for the strain measurements, is presented in the text and the formula used is derived in the Appendix.
Characterization of Galvanized Sheet Steel for Automotive Vehicle Bodies
Authors: Pearlstein F , Gallaccio A 
Published: February 2009

Abstract
Commercially available galvanised steel sheet materials, obtained from several sources and representing sinc coatings of conventional spangles (sinc crystal faces), minimized spangles, and diffusion alloy (galvanneal), were characterized for quality and performance. Thicknesses of the galvanised coatings were determined by chemical stripping (procedures for which are offered), by microscopic examination of cross-sectioned specimen, and by magnetic and eddy-current measuring devices. These methods were compared for reproducibility and suitability for general use. Corrosion resistances of the galvanised steels were determined following specific periods of exposure of specimens in 5% salt-fog environment.
Bare galvanized steel sheets having a minimum coating thickness of 14 µm and averaging about 22 µm completely resisted rusting for 72 h in salt-fog. Since longer exposure (96 h) in some cases resulted in rusting of the steel substrate, the 72-h exposure period was recommended for quality control purposes. The adhesive and protective value of a conventional paint system applied to the galvanized materials are discussed. Bead and spot weldings of the galvanized sheets were performed successfully; typical and feasible welding procedures are described. The amenability of the various galvanized materials to forming or shaping without flaking of or damage to the coatings was demonstrated.
Conclusions regarding the suitability of the test methods and their adoption are offered. Recommendations for use of the materials, application of preferred thickness measuring methods, and acceptance of corrosion resistance qualifying criteria are presented.
A Comparison of the Elevated Temperature Strength Loss in High Tensile Strength Graphite/Epoxy Composite Laminates Due to Ambient and Accelerated Aging
Authors: Hofer KE , Stander M , Rao PN 
Published: February 2009

Abstract
A comparison is made between ambient and accelerated aged panels and panels tested immediately after curing. Strength reductions as a function of time of aging and temperature for several orientations of laminates were determined. The effect of adding interlayers of glass scrim cloth between graphite plies was investigated. The high tensile strength graphite-epoxy material studied was Modmor® II graphite/Narmco® 5206 epoxy.
History Dependence in the Cyclic Stress-Strain Response of Wavy Slip Materials
Authors: Laird C , Finney JM , Schwartzman A , de la Veaux R 
Published: February 2009

Abstract
A conflict exists as to whether the saturated flow stress of a wavy slip metal cycled at high plastic strain amplitudes depends on history or not. To resolve this, mechanical tests have been carried out on heavily cold-worked copper and the structures studied by transmission electron microscopy. It has been found that, for any material, there exists a prestrain (dependent on many testing and material factors) below which cyclic stress-strain response is history independent and above which it is dependent. For severe prestrains, the cycling is insufficient to balance the dislocation structures in the cell walls, and the cells are more angular and misoriented than those which occur in annealed metal subjected to strain cycling.
Forest rodents provide directed dispersal of Jeffrey pine seeds
Authors: Briggs Jennifer S. , Wall Stephen B. Vander , Jenkins Stephen H. 
Published: February 2009

Some species of animals provide directed dispersal of plant seeds by transporting them nonrandomly to microsites where their chances of producing healthy seedlings are enhanced. We investigated whether this mutualistic interaction occurs between granivorous rodents and Jeffrey pine (Pinus jeffreyi) in the eastern Sierra Nevada by comparing the effectiveness of random abiotic seed dispersal with the dispersal performed by four species of rodents: deer mice (Peromyscus maniculatus), yellow‐pine and long‐eared chipmunks (Tamias amoenus and T. quadrimaculatus), and golden‐mantled ground squirrels (Spermophilus lateralis). We conducted two caching studies using radio‐labeled seeds, the first with individual animals in field enclosures and the second with a community of rodents in open forest. We used artificial caches to compare the fates of seeds placed at the range of microsites and depths used by animals with the fates of seeds dispersed abiotically. Finally, we examined the distribution and survival of naturally establishing seedlings over an eight‐year period.Several lines of evidence suggested that this community of rodents provided directed dispersal. Animals preferred to cache seeds in microsites that were favorable for emergence or survival of seedlings and avoided caching in microsites in which seedlings fared worst. Seeds buried at depths typical of animal caches (5–25 mm) produced at least five times more seedlings than did seeds on the forest floor. The four species of rodents differed in the quality of dispersal they provided. Small, shallow caches made by deer mice most resembled seeds dispersed by abiotic processes, whereas many of the large caches made by ground squirrels were buried too deeply for successful emergence of seedlings. Chipmunks made the greatest number of caches within the range of depths and microsites favorable for establishment of pine seedlings. Directed dispersal is an important element of the population dynamics of Jeffrey pine, a dominant tree species in the eastern Sierra Nevada. Quantifying the occurrence and dynamics of directed dispersal in this and other cases will contribute to better understanding of mutualistic coevolution of plants and animals and to more effective management of ecosystems in which directed dispersal is a keystone process.