bluuebunny/crossref_metadata_2025 huggingface dataset:
Three-Dimensional Transient Analysis of a Dynamically Loaded Three-Point-Bend Ductile Fracture Specimen
Authors: Nakamura T , Shih CF , Freund LB
Published: March 2009

A transient three-dimensional full-field analysis of a three-point-bend fracture specimen dynamically loaded into the fully yielded plastic state has been carried out. The specimen is rapidly loaded by means of a concentrated transverse force applied at midspan on the uncracked surface of the specimen. It is assumed that the material is ductile and fracture initiation occurs after substantial plastic deformation has developed in the uncracked ligament. Furthermore, it is supposed that the crack-tip conditions are such that the J-integral may be adopted as a characterizing parameter. We derive an expression for the local energy flux appropriate to a three-dimensional crack front. Based on this fundamental crack-tip flux integral, a domain integral representation for J which is naturally compatible with finite-element analysis is obtained. Using the domain integral, accurate pointwise and local values of J along a three-dimensional crack front can be extracted from numerically determined field quantities. The effect of transient loading, geometry, and plastic deformation on the variation of J along the crack front is examined. A purpose of the present study is to determine conditions under which the value of J at initiation may be inferred from quantities that are directly measurable in a dynamic fracture experiment. In an earlier paper, a transition time was introduced to provide a practical bound on the time range over which conditions of J-dominance prevailed and the deep-crack formula was applicable under transient loadings. The transition time concept is further examined in this paper. With the full-field solutions in hand, we comment on the suitability of proposed surface locations for measurements of moment and rotation, the input measurements for application of the deep-crack formula for J. Implications for fracture testing of tough materials at relatively high-loading rates are discussed.
An Experimental Study of the Validity of a Delta J Criterion for Fatigue Crack Growth
Authors: Jablonski DA
Published: March 2009

An experimental study was conducted to determine the validity of a delta J criterion for fatigue crack growth. Fatigue crack growth rates up to 0.10 mm/cycle were measured on compact tension specimens. Tests were conducted under delta J control using a computerized test system. Fatigue crack growth rates under variable delta J, J-increasing, constant delta J, and sloping-line test conditions were measured on 304 stainless steel and HY100 material. Linear elastic fracture mechanics crack growth rates were measured for comparison.

The results show that there is an excellent correlation between the fatigue crack growth rate and the effective J-integral range. The effective J-integral range was calculated from the area under the load/load-line displacement curve that was above the crack closure load. Correlation between the fatigue crack growth rate and the effective crack-opening displacement was poor. Correlations between the fatigue crack growth rate and the effective stress-intensity factor were poor for the 304 stainless steel and good for the HY100 material.

The crack closure behavior was measured for both materials. The crack closure loads were always compressive and either increased or decreased with crack length, depending upon the test type.
Oil and Resin Base (Oleoresinous) Caulking Compounds
Authors: Becker JW
Published: March 2009

Oil and resin base caulking compounds have been employed for sealing joints in buildings for many years. This paper describes the history, composition, and types of compounds. Back-up materials, movement capability, and life-expectancy are discussed. Effects of painting the compound, package stability, limitations, methods of testing, and specifications related to the compounds are included.
Polysulfide Sealants
Authors: Boller L
Published: March 2009

The paper deals briefly with the chemistry and formulation of polysulfide liquid polymers. It is primarily concerned with areas of application and performance of compounds based on the various liquid polymers. Criteria for the use of polysulfide sealants in the aircraft, automotive, building, and marine industries are given along with some case histories.
Solvent-Base Acrylic Sealants
Authors: Waters WI
Published: March 2009

Solvent-base acrylic sealants have been used in building construction for almost two decades; they are thermoplastic materials with good weatherability and exceptional adhesion to common building substrates. Although, initially, there was some difficulty in their manufacture, general formulating principals and physical properties are now common knowledge. Once an established formulation is obtained, the quality control of the product uses simple, standard test methods. These sealants must sometimes be heated to apply them, but the manufacturers usually supply the necessary accessories. When used within their movement capabilities, they have been successful in glazing, bedding, and caulking applications. There are various government, industrial, and international test methods and specifications to which these sealants conform.
Neoprene (Polychloroprene) Membranes
Authors: Thomas NF
Published: March 2009

Neoprene (polychloroprene) sheet has proven successful as a waterproof membrane in the construction industry. The general category of waterproof membranes includes between-slab plaza deck waterproofing, below-grade vertical wall waterproofing, bridge deck membrane between the structural deck and paving course, as well as exposed membranes such as roofing and substrate protection. Identification and interpretation of specific physical properties relate to successful product selection. One approach to product selection through testing is described as potential membrane waterproofing for bridge decks that are screened. In addition to product selection, installation procedures, details of expansion joints, penetration, and terminations are critical to successful performance of the membrane.
Lock-Strip Glazing Gaskets
Authors: Dallen JA , Paulus PV
Published: March 2009

The most recent developments in the design and application of lock-strip gaskets is covered in this paper, particularly those relating to high performance requirements. Guidelines for a successful glazing installation with particular attention to problem areas are also discussed.
Compression Seals
Authors: Brown H
Published: March 2009

This paper describes synthetic rubber compression seals. A brief summary of ASTM Specification for Cellular Elastomeric Preformed Gasket and Sealing Materials (C 509-70) is given. The basic design concept for use of compression seals for weatherproofing glass and panels in buildings is also reported.
Polyurethane-Polyepoxide Sealant
Authors: Spetz JL
Published: March 2009

Polyurethane-polyepoxide sealant is a two-package, on-site mixed, chemical curing sealant. It is formulated specifically to seal high-performance moving joints in modern precast and curtain wall type buildings.
Military Aircraft
Authors: Hackman LE
Published: March 2009

Military aircraft have utilized fiber reinforced composites for more than twenty years. The bulk of this use has been glass fiber reinforced plastics, which has provided both improved structural efficiency and lower cost. Recently, the advent of high modulus composites has led to its use in highly loaded, stiffness critical wings and control surfaces, as well as other structures.

This chapter details the major structural design approaches used for fiber composites in aircraft and summarizes several applications.
Chapter 2—Extraction, Replica Techniques
Authors:   Task Group E04.11.01
Published: March 2009

Small particles such as precipitates and included material in the matrix (such as inclusions) can be examined for shape, size, and distribution using the electron microscope. Thin surface films can also be examined. Using selected area electron diffraction, the particles or films can be identified if they are crystalline in form. Amorphous materials can not be identified by this technique because of diffuse and indistinct diffraction rings.
Extraction of Free Lime in Portland Cement and Clinker by Ethylene Glycol
Authors: Javellana MP , Jawed I
Published: March 2009

Free lime in portland cement and clinker has been determined by extraction with hot ethylene glycol. Our determinations show that times of 5–10 minutes and temperatures of 80–100°C are adequate. This method is as accurate as the ASTM method and has the distinct advantage of simplicity and rapidity.
Measuring KR-Curves for Thin Sheets
Authors: Ripling EJ , Falkenstein E
Published: March 2009

A modification of the tapered double cantilever beam specimen for measuring KR-curves of thin sheets is described. The modification consists of adhering properly contoured cover plates to the sheet to form a composite zero K-gradient (ZKG) specimen.

This testing procedure has a number of advantages over those presently used for plane stress testing:

1. K is proportional to the applied load and independent of crack length. Consequently, the specimen is stable, allowing for the collection of the complete KR-curve.

2. The testing procedure is simplified, and the instrumentation required to collect data, even at high rates, is relatively simple, since only load need be monitored.

3. Buckling is eliminated without the need of constraining members near the crack.

4. Cracking rate is related linearly to displacement rate.
Fracture Extension Resistance (R-Curve) Characteristics for Three High-Strength Steels
Authors: Judy RW , Goode RJ
Published: March 2009

New procedures for characterizing the fracture extension resistance of ductile metals have been established. The fracture extension resistance curve (R-curve), which delineates the increasing rate of plastic work to cause crack propagation in nonbrittle metals, is determined by using dynamic tear (DT) test procedures. The resistance parameter is the slope of the R-curve.

The effect of thickness on the R-curve slope was investigated for three high-strength steels of high, intermediate, and low resistance to ductile fracture. R-curves were determined for each steel in the full thickness (1 in.) and for thicknesses of 0.625 and 0.325 in. The R-curve slopes showed good agreement for each section size, and a transition in the fracture mode from flat fracture at short crack extensions to the metal's characteristic degree of shear fracture for long extensions was observed for each steel. The data can be described by an exponential equation involving fracture energy, specimen cross-section dimensions, and a constant, Rp, which is proportional to the R-curve slope. For each steel, Rp is unaffected by changing specimen geometry, thus indicating it to be a material property.
Mixing Zone Concepts
Authors: Fetterolf CM
Published: March 2009

There is no uniform approach to the designation of zones to accommodate liquid waste discharges into an aquatic receiving system without interference with other beneficial uses. This leads to confusion and in-decision among dischargers and enforcement agencies. Acceptance of universally adaptable guidelines would initiate understanding and progress. Such conceptual guidelines are proposed, including: initial establishment of the waste capacity of the receiving system; control of mass emission rate of critical materials; adoption of aesthetic criteria; establishment of water quality requirements in the mixing zone based on time exposure history; derivation of specialized criteria to permit overlapping mixing zones; limiting the total region of a waterbody devoted to mixing zones; assessment of damage to biota on a population basis; recognition that limited loss of living area may not be significant to populations; early acknowledgment that siting and discharge design can afford protection to uses; and that a case-by-case approach is essential to wise use of natural resources.
Bacteria and the Assessment of Water Quality
Authors: Bott TL
Published: March 2009

Bacteria are important in the assessment of water quality because certain organisms may be used as indicators of pollution of various types, and because bacteria possess diverse metabolic capabilities that bring about the mineralization of substances, many of which other organisms are unable to use. The limitations of the widely used coliform procedures are discussed and some new approaches to the detection of organisms of fecal origin are presented.

Methods for determining bacterial biomass are presented. However, measures of bacterial activity are more desirable because it is activity that will affect water quality. Some recent approaches to the measurement of bacterial growth and metabolism directly in natural habitats are presented.
Laboratory Measurement of the Durability of Paving Asphalts
Authors: Schmidt RJ
Published: March 2009

The objective of this study was to develop a practical laboratory test to measure reliably the relative durability of paving asphalts. An appropriate test must harden a wide variety of asphalts in the same order as do field exposures. The studies reported demonstrate that current asphalt durability tests do not properly relate to field hardening because they exaggerate unrealistically the volatile loss to obtain sufficient oxidative hardening. A microfilm exposure conducted in an RTF bottle exposed to the oven atmosphere through a short capillary is shown to prevent excessive volatile loss while permitting sufficient oxidation to take place. The functionality of this new RMF-C test is supported by three different correlations: a group of recent California highway test projects, the Z-W Test Project, and a group of asphalt concrete specimens aged for 100 days at 140 F (60 C). The data support the contention that the exposure is a valid simulation of the field hardening expected to occur in asphalt concrete pavements.
Problems in Manufacture of National Bureau of Standards Cast Metal Standard Reference Materials
Authors: Kennedy WR
Published: March 2009

A description is given of problems arising during manufacture of standard reference material castings for the National Bureau of Standards. Cast iron, steel, blast furnace compositions, ductile iron, and high temperature alloys are discussed. Techniques to effect sound structure and integrity in the end-product are given.
Paper Fiber Filters for Sampling Trace Metals in Airborne Particulate Matter
Authors: Kometani TY , Bove JL , Nathanson B
Published: March 2009

The standard collection filter medium for particulate air pollutants has been fiberglass. The high metal impurity content of glass and the tedious acid extraction procedure necessary to recover metals from particulates are great disadvantages when trace analysis is to be performed. Samples on paper filters, on the other hand, can be dry ashed to 500°C without serious loss of metals by volatilization. The filter is completely destroyed leaving only inorganic residue to be dissolved for analysis by atomic absorption spectrometry.

Analysis of New York City particulates collected on paper filters indicate that results obtained by dry ashing compare favorably with those of accepted methods such as wet ashing and low temperature ashing. Reported losses of metals during dry ashing of particulates on fiberglass filters are not necessarily due to volatilization as has been commonly supposed. Metals such as lead, zinc, copper, and cadmium are retained to glass to varying extents at high temperature either by formation of insoluble metal silicates or by physical entrapment by softened glass.
Color Evaluation of Foods—Correlation of Objective Facts with Subjective Impressions
Authors: Little AC
Published: March 2009

In the early 1950's, a symposium entitled Color in Foods was arranged under the aegis of the National Academy of Sciences, National Research Council. The proceedings of that symposium have not to this day been superseded by a more up-to-date consideration of the state of knowledge as it has evolved since then.

At that time, considerable discussion was focused on the question of the validity of relating objective data to some visually determined and presumably imprecise scale. Because the opportunity has not presented itself to continue the vigorous exploration of this and other unresolved questions, the reservations and recommendations expressed in the proceedings stand unchallenged.

It is the purpose of this report to present a detailed discussion of the procedural framework developed by us to provide the basis for developing solutions for specific commodities and for specific purposes. The essentials include the development of model systems constructed to vary in known and controlled fashion along the requisite dimensions of color; the determination of optimum conditions for analyzing samples precisely and reproducibly for changes in physical and chemical properties which underlie changes in perceived color; the definition and construction of psychological scales which provide data relevant to the case in point; and finally, the demonstration of a highly significant relationship between visual evaluations and physically determined quantities. Thus, for different products, the same conceptual model is used; yet the procedural details may differ widely depending on the constraints imposed by physical and chemical characteristics of the sample and the specific requirements of the case. The feasibility of the approach will be explored with reference to actual examples.
Relationship of Instrumental Measurements to Visual Impressions of Potato Chip Color
Authors: Yeatman JN , Aulenbach BB
Published: March 2009

A method was developed for preparing flat potato chips suitable for colorimetric measurement and visual evaluation. Flat potato chips were evaluated by three techniques: (1) colorimetric, including and excluding ultraviolet (UV) light in measuring beam to determine fluorescence effects; (2) spectrophotometric (380 to 740 nm), alternately backing chips with black or white reflector to permit calculation of light scattering; (3) visual, under controlled illumination by an experienced panel using a simple color-scoring system.

Excluding UV light increased Hunter aL and bL values. Although visual color scores under two luminaires (UV included and UV somewhat attenuated) were similar, greater attenuation of the UV light might affect visual impressions. Visual scores were highly correlated with Hunter L and aL, indicating that these instrumental measurements could be used to predict visual impressions of chip color. Munsell notations of chip color derived from spectrophotometric measurements backed with white reflector matched Munsell papers better than notations derived from data corrected for light scattering.

Color photographs were made of a series of flat potato chips with a Munsell gray scale in the frame register, permitting precise reproduction of a new visual color guide. The method of flat chip preparation for instrumental measurement and the visual color guide are offered as improved optional procedures in U.S. Standards for Grades of Potatoes for Processing.
Appearance: Likes and Dislikes
Authors: Rubacky EP
Published: March 2009

The importance of any consensus of people's likes and dislikes, and the practical value thereof, are often obtunded by the large variances of human hedonic behavior within and between people. Means to cope with these problems by the handling of such data, and means by which to constrain the magnitude via suitably high speed data collection systems are reviewed. An historical case is cited to show the sensitivity of people's likes and dislikes versus concentration changes, and it is argued that hedonics does not conform with laws of psychophysical intensity for specific or highly focal sensory research. A case is made from broad scope questioning and from actual stimulus work that general human hedonic behavior may or may not agree with that from specific focal studies. A method for classifying such behaviors into nine hedonic types is described together with its application to quantifying changes, or impacts. Visual hedonic data suggest hedonic behavioral patterns exist, are not dependent upon the rating technique, and are essential to analyses or interpretations if a consensus with meaning is to result. Sensory intensity functions, however useful themselves, are deemed inadequate substitutes to measure where hedonic consensus is needed, as well as misleading.
Sensory Evaluation: Potentials for Precision and More General Application in Science and Technology
Authors: Pickett RM
Published: March 2009

This paper presents a case for devoting increased attention to the refinement and general application of sensory evaluation in science and technology. Today, probably because of immense recent achievements in instrumentation and automation, the scientific and technical community generally looks toward instrumentation to provide measures of objects and events. This inclination may be generally appropriate, but we caution: (1) that it may inhibit seeking significant achievable refinements in current sensory evaluation methods that may have to fill long gaps between now and the time effective instruments are developed; and (2) that it may lead to acceptance of instruments with effectiveness that falls far short of what could be attained with refined sensory evaluation techniques.
Property Changes Resulting from Impurity-Defect Interactions in Iron and Pressure Vessel Steel Alloys
Authors: Smidt FA , Sprague JA
Published: March 2009

The effects of 0.3 atomic percent copper, vanadium, nickel, and phosphorus and 0.1 atomic percent carbon addition on the irradiation response of pure iron have been investigated to clarify the role of copper and phosphorus in embrittlement of pressure vessel steels. Compression tests and transmission electron microscopy (TEM) analysis of the aforementioned alloys and selected heats of pressure vessel steel and weldment have been examined after irradiation to fluences of 2.5 × 1019 and 4.5 × 1020 n/cm2 > 1 MeV at 290 C (550 F). Copper is found to influence the properties by promoting nucleation of defect aggregates, probably vacancy loops, at low fluences, thus increasing the radiation strengthening and shifting the transition temperature upward. Small voids were observed in the 0.3Ni, 0.3Cu, and 0.1C alloys and in pure iron but not in 0.3V or 0.3P alloys.
Damage-Function Analysis of Neutron-Induced Embrittlement in A302-B Steel at 550 F (288 C)
Authors: Serpan CZ
Published: March 2009

A damage function was derived for neutron-induced increases in the brittle to ductile transition temperature (ΔTT) of ASTM A302-B steel, for temperatures of 550 to 585 F (288 to 307 C). The damage function is a series of weighting factors for the damaging capacity of neutrons of all energy groups in a reactor spectrum that indicate the relative importance of specific energy-group neutrons to the damaging process. The damage function showed that neutrons of energies greater than 1 MeV would account for about 75 percent of the ΔTT, but that neutrons of energies greater than 0.1 MeV would account for over 94 percent for virtually every spectrum evaluated. Furthermore, thermal neutrons were seen to contribute less than 5 percent of the ΔTT, and this only if the thermal population were an order of magnitude greater than the fast neutron population. A method was then developed for plotting neutron fluence (>0.1 MeV) weighted by the damage function that provides excellent correlation of the experimental 550 to 585 F (288 to 307 C) irradiation data for diverse reactor environments. Adequate correlations of data can also be achieved (using only fluences > 0.1 MeV) if conditions preclude inclusion of the damage function. This is a totally rational approach for correlating experimental radiation damage results that has the advantage of being least susceptible to errors in flux spectrum and neutron dosimetry measurements.
A Comparison of the High-Temperature Damage Structures in Accelerator and Reactor Irradiated Molybdenum
Authors: Eyre BL , Evans JH
Published: March 2009

The damage structures produced in high-purity molybdenum by neutrons in a fast reactor and by 2-MeV nitrogen ions in an accelerator have been compared using transmission electron microscopy (TEM). The irradiations have been carried out in the temperature range 450 to 900 C (842 to 1652 F) and doses in the range 10 displacements per atom (dpa) to 200 dpa. Over these ranges the damage structures can be defined in terms of a dislocation component and a void component. Several features of the void structures are found to be independent of the method of damage production, although the dose rate differences affect the temperature range and lower threshold dose for the formation of visible voids. With regard to the dislocation component of the structures, there is a qualitative similarity in distribution of loops and network dislocations between the reactor- and accelerator-irradiated specimens. However, a detailed analysis of the nature of the loops reveals important differences. The loops in reactor-irradiated specimens are predominantly interstitial in nature whereas the loops in accelerator-irradiated specimens containing voids are predominantly vacancy in nature. This result is discussed in detail together with other aspects of the comparative study.
Ordered Defect Structures in Irradiated Metals
Authors: Kulcinski GL , Brimhall JL
Published: March 2009

The production of ordered defect structures in metals by neutron and charged particle bombardment is reviewed. Specific examples of a cubic array of aligned defect clusters are shown in nickel bombarded with 5-MeV nickel ions to 15 displacements per atom (dpa). The effect appears to occur only at temperatures between 280 and 450 C (536 and 842 F). Random defect arrays were found after 40, 180, 525, and 500 C (104, 356, 977, and 932 F) irradiation.

Ordered arrays of voids are shown in Ni nickel-irradiated to 300 to 400 dpa at 525 C and in molybdenum, Mo-0.5Ti, titanium-zirconium molybdenum alloy (TZM), columbium, tungsten, and tantalum irradiated with both neutrons and heavy ions. The structure of the voids is consistent with the parent lattice, that is, face centered cubic (fcc) in nickel and body centered cubic (bcc) in the refractory metals. A summary of the information reported to date reveals that the ratio of the lattice parameter of the void superlattice divided by the void radius varies from 5 to 17. The general features of the ordered void lattice are discussed in view of current theories that depend on strain interactions between the voids, anisotropic interstitial atom fluxes, and an approach to steady state at high displacement values.
A Diffusion Model for the Effect of Applied Stress on Void and Loop Growth
Authors: Straalsund JL , Guthrie GL , Wolfer WG
Published: March 2009

The effect of a general state of stress on swelling has been considered in a theoretical void growth model. Angular-dependent loop growth has been incorporated into the model in order to include the effects of shear stress. It has been found possible to consider the effects of stress on void and loop growth as a relatively simple deformation process. We define the stress effect as follows: where (dϵi/dt)σ=0 is the strain rate associated with the isotropic swelling that would occur in stress-free conditions. For an applied stress having both hydrostatic and shear components, the hydrostatic component provides a driving force for isotropic volume swelling and the shear component causes a shape change. The total deformation process (stress-induced volume increase and shear) may be represented by the relation: where the σ's are applied tensile stresses and the i, j, K are the principal axes. K and ν are two material parameters that depend upon microstructure (dislocation density, void number density, and void size) but do not depend upon flux. K depends strongly on temperature whereas ν is independent of temperature. The extent to which plastic flow must accompany stress-assisted swelling is governed by the parameter ν. As ν approaches 1/2, the deformation process becomes pure shear. It is found that the value of ν is bounded and lies between -1/3 and +1/2. Thus, except under the application of purely hydrostatic stress, stress-assisted swelling cannot be completely shear-free. When transmission electron microscopy (TEM) data for neutron-irradiated solution-treated Type 316 stainless steel were used, the values of ν were found to lie between 0 and 0.5. For cold-worked steels, ν is expected to lie in the upper part of the range just given. The significance of the present results becomes evident in the analysis of fuel pin profiles. For isotropic swelling with no plastic flow, the fractional change in fuel pin diameter is 1/3 the fractional isotropic volume change. However, for stress-assisted swelling, the relation may be much different and depends upon the parameter ν. For a biaxial stress state of the type that occurs in pressurized cylindrical tube, for example, Δ D/D ≈ 0.7 when ν = 0.1, whereas ΔD/D≈ 1.4 ΔV/V when ν = 0.3.
Influence of Neutron Spectrum and Microstructure on the Postirradiation Creep-Rupture Behavior of an Austenitic Cr-Ni-Ti-B Steel
Authors: Böhm H , Wassilew C
Published: March 2009

The influence of neutron irradiation on the postirradiation creep rupture properties of a 15Cr-15Ni-Ti-B steel and their dependence on microstructure and neutron spectra were studied. The steel was tested in three conditions: (a) solution treated at 1150 C (2012 F), (b) solution treated and aged at 1025 C (1877 F), (c) solution treated and aged at 900 C (1652 F). The conditions are characterized by an increasing amount of TiC precipitates going from treatment (a) to (c). The irradiations were carried out in the BR 2 reactor (Mol/Belgium) to a fast neutron fluence of 2 × 1021 n/cm2 (E >0.1 MeV) and in the FR 2 reactor (Karlsruhe) to a thermal neutron fluence of 3 × 1020 n/cm2. The ratio of thermal to fast neutron flux was about 0.66 for BR 2 and 30 for FR 2 irradiations. The irradiation temperature was about 70 C (158 F). The postirradiation creep rupture tests were carried out at 650 C (1202 F).

The changes in creep rupture properties after irradiation were found to be strongly dependent on the neutron spectrum and the thermal pretreatment of the steel. The main results can be summarized as followed: 1. The fast thermal neutron irradiation in the BR 2 caused an increase in rupture life and decrease in creep rate of the steel in the solution-treated condition and also, but to a lower extent, in the 1025 C (1877 F) aged condition. With increasing stress the difference between the irradiated and unirradiated values diminished. 2. Irradiation in the FR 2 caused a decrease in rupture life and increase in creep rate of the 1150 and 1025 C (2102 and 1877 F) annealed conditions. The effect was more pronounced in the solution-treated than in the 1025 C annealed condition. The difference between the irradiated and unirradiated values decreased with decreasing stress. 3. There were no remarkable changes in creep rate and rupture life after irradiation of the steel in the 900 C (1652 F) annealed condition.

The results are discussed in terms of radiation-influenced precipitation processes superimposed by radiation-induced high-temperature embrittlement.
Effect of Neutron Irradiation on Vanadium
Authors: McIlwain JF , Chen CW , Bajaj R , Wechsler MS
Published: March 2009

The effect of neutron irradiation on vanadium containing 50 to 800 weight ppm oxygen was studied using electrical resistivity, internal friction, and mechanical property measurements. The resistivity and internal friction specimens were irradiated to 3 × 1018 neutrons/cm2 (E > 1 MeV) at −190 C(−310 F) and the tension test specimens were irradiated to 1.2 x 1019 neutrons/cm2 (E > 1 MeV) at 106 C (223 F). Postirradiation annealing treatments were performed up to 220 C (428 F) for the resistivity and internal friction specimens and up to 520 C (968 F) for the tension test specimens.

Isochronal resistivity annealing measurements exhibited annealing stages at 170 C (338 F), 30 C (86 F), and −105 C(−157 F). The highest temperature stage (near 0.2 Tm, where Tm is the melting temperature) is attributed to the motion of interstitial oxygen to radiation-produced defect clusters and loops, where the oxygen is effectively removed from solid solution. This conclusion is based on the observations that: (a) the annealing activation energy is 1.1 ± 0.1 eV, close to the oxygen migration energy of 1.23 eV; (b) the magnitude of the annealing stage increased with increasing oxygen concentration; and (c) the decreases in oxygen concentration in solid solution upon annealing deduced from the decrease in resistivity and the decrease in the oxygen internal friction peak are in substantial agreement. The origins of the two lower temperature peaks are unknown, although it is speculated that hydrogen may be involved in the peak at -105 C (−157 F).

The yield stress measurements indicate that radiation exposure at 106 C (223 F) results in greater radiation hardening for specimens with larger oxygen concentration. Also, the further increase in strength upon postirradiation annealing (radiation-anneal hardening) is enhanced by increasing interstitial impurity concentrations.
Chapter 2—Techniques, Procedures, and Practices of Sampling of Concrete and Concrete-Making Materials
Authors: Abdun-Nur EA
Published: March 2009

Millions upon millions of dollars change hands daily in various segments of the concrete industry, based on evidence obtained from samples. Yet, in most instances, the sample is obtained in an indifferent manner by someone who is ignorant of the basic principles of sampling (frequently a laborer or warehouseman), the use to which the sample is to be put, the tests to be performed on the sample and the final decisions to be based on or derived from the test results—all very important factors that should be considered in the sampling process. There appears to be no adequate appreciation of the importance of sampling by those who should be concerned with the problems resulting from poor sampling—those who have to make important decisions and set policy based on test results from samples—despite the cost of the large volume of samples and testing in the concrete field and the larger economic significance of conclusions which are derived from these.
Chapter 3—Statistical Considerations in Sampling and Testing
Authors: Arni HT
Published: March 2009

It is not the purpose of this chapter to provide a short text on general statistical methods and procedures. Many sources, some of which are listed in the references, are already available that provide such information ingreat detail. Rather, the purpose is to identify situations that are peculiarto the testing and evaluation of cement and concrete in which statistical techniques can be of value, to suggest techniques that are appropriate to use in these situations, to provide, by references to other sources as much as possible, information about how to use these techniques in the given situations, and, last but not least, to point up some of the pitfalls and misconceptions that often cause problems in the application of statistical techniques.
Chapter 12—Strength
Authors: Derucher KN
Published: March 2009

Whether used in buildings, bridges, pavements, or any other of its numerous areas of service, concrete must have strength, the ability to resist force. The forces to be resisted may result from applied loads, from the weight of the concrete itself, or, more commonly, from a combination of these. Therefore, the strength of concrete is taken as an important index of its general quality. Hence, tests to determine strength are the most common type made to evaluate the properties of hardened concrete, because (a) the strength of concrete, in compression, tension, shear, or a combination of these, has in most cases a direct influence on the load-carrying capacity of both plain and reinforced structures; (b) of all the properties of hardened concrete, those concerning strength usually can be determined most easily; and (c) by means of correlations with other more complicated tests, the results of strength tests can be used as a qualitiative indication of other important properties of hardened concrete [1].
Chapter 15—Nondestructive Tests
Authors: Whitehurst EA , Malhotra VM
Published: March 2009

For many years one of the goals of those engaged in the control of concrete quality and in the service behavior of concrete has been the development of suitable nondestructive tests to supply the information desired. To be of greatest usefulness, such tests should be applicable to concrete in the structure.
Chapter 20—Corrosion of Embedded Materials Other than Reinforcing Steel
Authors: Erlin B , Woods H
Published: March 2009

This chapter deals with materials, other than conventional reinforcing steel, which are sometimes used in conjunction with concrete. As the title of this chapter implies, emphasis will be given to the possible degradable aspects relative to their use, and conditions that may render them serviceable or unserviceable.
Chapter 23—Resistance to Weathering
Authors: Newlon H
Published: March 2009

The purpose of this paper is to discuss the significance of currently standardized testing procedures for evaluating the resistance of concrete to weathering under service conditions. The published literature on the subject is extensive and only a somewhat superficial treatment can be given in a brief paper. The reader should consult the similar papers in earlier editions of this special technical publication by Scholer [1,2], Powers [3], and Arni [4]. A monograph by Woods [5] presents a comprehensive picture of durability, and one by Cordon [6] discusses freezing and thawing in detail. Perhaps the most comprehensive treatment of the influence of aggregates on resistance to freezing and thawing is that of Larson et al [7]. An extensive annotated bibliography on concrete durability published by the Highway Research Board (HRB) in 1957 [8] with a supplement in 1966 [9] contains 534 citations. Unfortunately this bibliography has not been updated. The report of ACI Committee 201 on Durability of Concrete [10] contains valuable recommendations for production of concrete to provide resistance to the various destructive processes encountered in field exposures. The ACI Symposium [11] on durability of concrete contains 17 papers on various theoretical and operational aspects of producing durable concrete.
Chapter 30—Lightweight Concrete and Aggregates
Authors: Lewis DW
Published: March 2009

Both “lightweight concrete” and “lightweight aggregate” are general terms which include a wide variety of products and are frequently subject to varying definitions. Concrete lighter in weight than that usually obtained with “normal weight” aggregates (gravel, air-cooled blast-furnace slag, and crushed stone) may be produced by several methods: 1. Lightweight aggregate concrete, which is comparable to conventional concrete except for the use of lightweight materials as all or part of the aggregate. 2. Cellular or foam concrete, where the light weight is caused primarily by inclusion of a large amount of air or gas, usually 25 percent or more. A suitable foam or foaming agent is combined with cement and water, either with or without other ingredients such as sand or pozzolanic fines. 3. No fines or “popcorn” concrete, with the light weight produced by high air contents or specially graded aggregates having little or no fine material or both. Either lightweight or normal weight aggregates may be used.
Chapter 31—Packaged, Dry, Combined Materials for Mortar and Concrete
Authors: Carter AC
Published: March 2009

Packaged, dry, combined materials for mortar and concrete are combinations of cementing materials and aggregates which require only mixing with proper quantities of water to be ready for use. The packages, varying in mass from 5 to 41 kg (10 to 90 lb) generally are available at the producing plant, building supply, and hardware stores, as well as some supermarkets. The general trend is to mix the various ingredients thoroughly before packaging in moisture-resistant multiwall paper bags. Some products introduce the ingredients into the package separately without prior mixture. Still others package the cement separate from the aggregates. Since the original publication of ASTM Specification for Packaged, Dry, Combined Materials for Mortar and Concrete (C 387) in 1956 and during subsequent revisions of that specification covering these materials which will be discussed later in this paper, the buying public has become increasingly specification conscious.
Chapter 34—Grading
Authors: Price WH
Published: March 2009

The influence of aggregate gradings on the properties of concrete has been extensively discussed in the technical literature during the past 125 years and many methods for arriving at “optimum” or “ideal” gradings have been presented. However, none of these has been accepted as being universally applicable, because of economic consideration, differences in particle shape and texture of the aggregates, and the effects of entrained air and amount of cementitious material contained in the concrete [1–25].
Chapter 36—Weight, Density, Absorption, and Surface Moisture
Authors: Mullen WG
Published: March 2009

Aggregates in stockpiles are collections of various sizes of irregularly shaped particles often with rough or convoluted surfaces, sometimes with pores and wrinkles or crevices that hold water. Because the particles do not fit together nicely, spaces called voids are left between them and the whole pile contains water in the pores and on the surface of each particle, even when located on the edge of the African desert. In order to use these aggregates as the largest part of a concrete mixture, five factors must be determined: (1) the volume of voids in order to fill them with paste and to float the particles apart with an excess of paste, (2) the volume that solids will contribute to the concrete mix, (3) the specific gravity in order to convert volume to weight, since most concrete is batched by weight, (4) the absorption because it affects the specific gravity that is used, and (5) the surface moisture because mixing water must be adjusted to compensate for it.
Predicting the Fate of Chemicals in the Aquatic Environment from Laboratory Data
Authors: Branson DR
Published: March 2009

Reasonable predictions of the fate of chemicals in the aquatic environment can be made from laboratory data. Some of the important data include evaporation, degradation, bioconcentration, and particulate adsorption. One of the more promising approaches for predicting fate is called “environmental rates approach” and requires that the laboratory data be expressed as rates. Suitable material balance models can then incorporate the environmental rates and predict exposure concentrations from a given rate of entry.

The “model ecosystem approach” is another way to predict fate. To evaluate model ecosystem data, the biodegradability index and ecological magnification values are compared with the biochemical oxygen demands and bioconcentration factors for a few benzene derivatives. Both types of data identify aniline and benzoic acid as the most susceptible to biodegradation in the series. Both also identify chlorobenzene and pentachlorophenol as the most accumulative in the series. Neither compound is as accumulative as DDT.

The main advantages of the environmental rates approach are the predictability of environmental concentrations at several points in time and the fundamental understanding of what happened to the chemical. The main advantages of the model ecosystem approach are the existing large data base and the identification of stable breakdown products as part of the test method.
Criteria and Rationale for Decision Making in Aquatic Hazard Evaluation (Third Draft)
Authors:   Aquatic Hazards of Pesticides Task Group of the American Institute of Biological Sciences
Published: March 2009

History and Charge to the Task Group—Among the purposes of the American Institute of Biological Sciences (AIBS) are advancement of biological science and service to society. In pursuance of these objectives, the AIBS offers advisory services, in matters relevant to biology, to federal agencies and other national organizations. The mechanism most frequently employed is formation of advisory panels or task groups drawing participants from among the 12 000 individual members of AIBS and from those of the 57 affiliated biological subject matter societies whose collective membership exceeds 80 000 distributed through government, industry, and academic organizations.
Fracture Mechanics and Composite Materials: A Critical Analysis
Authors: Zweben Carl
Published: March 2009

The emergence of advanced filamentary composite materials as a structural material comes at a time of increasing concern over reliability. This places increasing emphasis on the ability to characterize the fracture and fatigue behavior of these materials. The importance of understanding fracture behavior is intensified because of the characteristic statistical variability in material strength and the observation of fracture phenomena that are significantly different from those of metals. This paper discusses what appear to be the three main approaches being pursued. The first applies classical fracture mechanics (CFM) on a macroscopic level, treating composites as homogeneous, anisotropic materials. The second recognizes material heterogeneity and applies CFM to the problems of crack propagation in the matrix and fiber phases and interfaces separately. The third method, which might be called the material modeling approach, uses approximate models in order to represent the major effects of heterogeneity and simplify the analysis. The advantages and limitations of each of the three approaches are discussed and predictions compared with available experimental data. The emphasis is on material modeling, and it is shown that with the use of relatively simple models it is possible to predict many of the unusual fracture phenomena that are observed.
Data Averaging of Anisotropic Composite Material Constants
Authors: Wu EM , Jerina KL , Lavengood RE
Published: March 2009

Material parameters which are dependent on direction of orientation can be best represented by tensors of appropriate ranks. Using tensor transformation rule and associated scalar invariants of the tensor, experimental data can be averaged and reduced to compact constants for engineering documentation and retrieval. Examples on data averaging of composite swelling coefficients and elastic compliances illustrate the simplicity and viability of this tensor averaging methodology.
Some Important Aspects in Testing High-Modulus Fiber Composite Tubes in Axial Tension
Authors: Sullivan TL , Chamis CC
Published: March 2009

Tubular specimens were potted in metal grips to determine the feasibility of this gripping method in applying multiaxial loads. Strain gage rosettes were used to assess grip transitional strains, through thickness strain variation and strain variations along the tube length and circumference. The investigation was limited to loading 0, 45, ±45, and 90-deg graphite/epoxy and glass/epoxy tubes in axial tension. Results include modifications made to the grips to reduce transitional strains, illustrations of the tube failure modes, and some material properties. The gripping concept shows promise as a satisfactory technique for applying multiaxial loads to high-strength, high-modulus fiber composite tubes.