bluuebunny/crossref_metadata_2025_split huggingface dataset:
Comments on Erosion Tests Conducted in an ASTM Interlaboratory Test Program
Authors: Steller K , Reymann Z , Targan M , Hammitt FG 
Published: February 2009

Abstract
New results from the Polish Academy of Sciences are compared with previously published results of an ASTM interlaboratory test of the erosion effects of vibratory cavitation and liquid impact facilities on three metals. In the studies reported here vibratory and rotating disk facilities were used. A new evaluation of the results of all the tests and corresponding scaling effects has been made, and the results of erosion tests using the vibratory method, the rotating disk method, and the liquid impact method have been compared.
A Correlative Study Between Analysis and Experiment on the Fracture Behavior of Graphite/Epoxy Composites
Authors: Yeow YT , Morris DH , Brinson HF 
Published: February 2009

AbstractSeveral of the current approaches to the analysis of the fracture behavior of notched fiber-reinforced composites are reviewed and discussed. Experimental results of fracture tests on uniaxial tensile strips containing center cracks are presented. Photoelastic coating photographs illustrate the regions of high stress gradient ahead of the crack for the various laminates investigated, namely, [0 deg]8s, [0 deg/90 deg]4s, [± 45 deg]4s, and [0 deg/±45 deg/0 deg]2s. A brief discussion of damage zones and fracture planes is given. Comparisons between several two-parameter fracture models and a new boundary integral equation approach of Cruse are made and comparisons between predictions of fracture strength using these models and experimental results are presented.
Evaluation of Erosion Resistance of Metallic Materials and the Role of Material Properties in Correlations
Authors: Syamala Rao BC , Veerabhadra Rao P , Lakshmana Rao NS 
Published: February 2009

AbstractA study of the correlations between material properties and normalized erosion resistance (inverse of erosion rates) of various materials tested in the rotating disk and the flow venturi at various intensities indicates that different individual properties influence different stages of erosion. At high and low intensities of erosion, energy properties predominate the phenomenon, whereas at intermediate intensities strength and acoustic properties become more significant. However, both strength and energy properties are significant in the correlations for the entire spectrum of erosion when extensive cavitation and liquid impingement data from several laboratories involving different intensities and hydrodynamic conditions are considered. The use of true material properties improved the statistical parameters by 3 to 37%, depending on the intensity of erosion. It is possible to evaluate qualitatively the erosion resistances of materials based on the true stress-true strain curves.
Fundamentals of Combustion Toxicology in Fire Hazard Assessment
Authors: Packham SC , Hartzell GE 
Published: February 2009

Abstract
This paper discusses fundamental principles of combustion toxicology and the application of those principles in formulating test protocols and research strategies aimed ultimately toward smoke toxicity hazard assessment and the influence of materials thereupon. It offers a review of principles basic to combustion toxicology to serve as introductory reading for fire technology professionals not generally familiar with the biological aspects of applied fire research and testing. While some methods of contemporary significance are referred to or discussed, this paper is not intended to be an exhaustive review or analysis of laboratory methods that have been applied in evaluating toxicological properties of smoke.
This paper also addresses the basic issues of the assessment of toxic hazards to life and how laboratory methods may be applied in determining whether the choice of one material over another would significantly alter potential toxicological threats to life. Some approaches to laboratory assessments are given involving time-dependent bioassays of toxicological effects caused by allowing materials to perform as they would in a real fire. This paper is intended to open the way to the complex area of smoke toxicity hazard assessment in the laboratory in a relevant and practical manner.
Correlation of Fiber Composite Tensile Strength with the Ultrasonic Stress Wave Factor
Authors: Vary A , Lark RF 
Published: February 2009

Abstract
An acoustic-ultrasonic technique was used to indicate the strength variations of tensile specimens of a graphite/epoxy composite. A “stress wave factor” was determined and its value was found to depend on variations of the fiber-resin bonding as well as fiber orientation. The fiber orientations studied were 0 deg (longitudinal), 10 deg (off-axis), 90 deg (transverse), [0 deg/±45 deg/0 deg] symmetrical, and [±45 deg] symmetrical. Correlations indicated that the stress wave factor can predict variations of the tensile and shear strengths of composite materials. The method was also found to be sensitive to strength variations associated with microporosity and differences in fiber/resin ratio.
Optimization of the Electrical Potential Technique for Crack Growth Monitoring in Compact Test Pieces Using Finite Element Analysis
Authors: Aronson GH , Ritchie RO 
Published: February 2009

AbstractFinite element procedures are used to optimize the efficiency of the electrical potential technique for monitoring the initiation and slow growth of cracks, as applied to the compact tension fracture test piece. An analysis of various configurations of current input and potential measurement lead placement is performed to optimize the accuracy, sensitivity, and reproducibility of measurement and to maximize output voltages. Numerical calibration curves are computed for selected configurations and are confirmed by experimental measurements.
Effects of Temperature on the Behavior of Metals Under Erosion by Particulate Matter
Authors: Gat N , Tabakoff W 
Published: February 2009

Abstract
The effect of temperature on the erosion of metals by solid particles is studied. Properties that, as the temperature increases, decrease the metals' resistance to erosion (Type I) are identified, as are other properties that increase their resistance to erosion (Type II). The removal of erosive material is accomplished through the simultaneous action of several mechanisms. Under given test conditions (such as angle of impact, particle shape, and hardness) one mechanism is likely to dominate. Whether erosion increases or decreases as the temperature increases depends on the dominant erosion mechanism because some mechanisms are affected by Type I factors while others are affected by Type II factors. This dependence may change, however, at various ranges of the temperature scale. At homologous temperatures (the ratio between the actual temperature of the material and its melting temperature, in absolute degrees) above 0.5, Type II factors dominate most erosion mechanisms. Of particular interest are the brittle-to-ductile transition temperature and the recrystallization temperature.
Concrete Core Strength—The Effect of Length to Diameter Ratio
Authors: Meininger RC , Wagner FT , Hall KW 
Published: February 2009

Abstract
The ASTM Method for Obtaining and Testing Drilled Cores and Sawed Beams of Concrete (C 42–68) currently contains length to diameter ratio correction factors for soaked cores but not dried cores. However, it is widely recognized that for structures which will be substantially dry in service dried cores are more appropriate. It is sometimes difficult—because of constraints of aggregate size, reinforcing bar placement, and member dimensions—to obtain drilled cores of the preferred dimensions, with a length twice the diameter. Research performed in two laboratories involving the drilling and testing of a large number of 4-in. (102-mm) diameter soaked and dried cores with length to diameter ratios of 1.0, 1.25, 1.5, 1.75, and 2.0, taken from six structural-size members, indicates that the same correction factors can be used for both moisture conditions and that the factors now in ASTM Method C 42–68 should be lowered slightly. In addition, data were gathered on the effect of end preparation procedure on core strength. For the methods used (three capping procedures and grinding of the ends) no important differences in measured strength were noted.
A Simple Ductility Tester for Metal Films
Authors: Nakahara S , Okinaka Y , Turner DR 
Published: February 2009

Abstract
A simple apparatus for measuring the ductility of metal films is described. The specimen is held rigidly between two metal plates with circular openings while a metal ball is slowly pushed upwards until the metal film ruptures. The distance the metal ball travels between the point where it first makes contact with the film and that where the film ruptures is observed. The ductility is determined from a graph which relates this distance to elongation. Reproducibility of the measurement is better than ± 10%. The apparatus is compact, portable, and simple to operate. It is recommended where a simple, yet reproducible, technique for ductility measurement is needed on a routine basis.
Review of New Developments in Crack Propagation Studies
Authors: El Haddad MH , Topper TH , Mukherjee B 
Published: February 2009

AbstractThe application of fracture mechanics concepts to characterize crack growth at low and high temperatures under cyclic, creep, and creep-fatigue conditions is reviewed. The applicability and limitations of various fracture mechanics techniques in predicting cycle- and time-dependent crack growth are discussed. Also, applications of fracture mechanics to predict the fatigue life of various components and the behavior of cracks at near-threshold conditions are discussed with an emphasis given to the growth of small cracks.
Quenching, Tempering, and Aging Chromium-Molybdenum-Vanadium Cast Steels
Authors: Coulon PA , Leymonie C , Saisse H , Thauvin G 
Published: February 2009

AbstractThe usual specifications for Cr-Mo-V steel castings fix modest levels of yield strength (350 to 450 MPa) in the hope of obtaining acceptable toughness. But this optimism sometimes leads to disappointment when only the components themselves are considered and not the attached parts. Tests carried out on Cr-Mo steel casings that have 100 000 h or more of service life show that, if toughness is sufficiently high in the as-received condition, and if certain precautions are taken into account at start-up, one may accept service embrittlement and even allow casings that reveal cracks caused by creep or thermal fatigue to remain in service. The aim of the work discussed in this paper has been to compare different grades of Cr-Mo steel distinguished in particular by chromium and nickel contents. Two subjects have been dealt with: the influence of the chemical composition on the optimal conditions of hardening and tempering and the preliminary study of age embrittlement (evaluated by the translation of Charpy V-notch and ductile fracture toughness transition curves).
A Method for the Determination of the Surface Area of Fine Aggregate in Bituminous Mixtures
Authors: Craus J , Ishai I 
Published: February 2009

Abstract
The paper describes a basic analytical method for calculating the surface area of fine aggregate particles (sands and fillers). Equations were derived for direct determination of the specific surface using data of actual size distribution, fineness, and shape properties of the particles. Practical calculation examples are given and compared with other conventional methods and with experimental determination of the surface area. In general, the method is flexible and affords a desirable degree of accuracy according to a proper partitioning of the size range into fractions. Results of the calculated surface areas were very close to values obtained experimentally. This indicates the advantages of the suggested method over some other useful methods for surface area calculations. The suggested method is basic and general and can be applied to any technology where the surface area of fine particles is an important factor.
The Effect of Orientation on the Analysis of Shape and Texture of Concrete Aggregates by the Modified Fourier Method
Authors: Czarnecka ET , Gillott JE 
Published: February 2009

Abstract
Two sorts of concrete, one prism of each, were investigated. One concrete prism was made with natural partly crushed gravel aggregate and the other, with 2.5-cm long by 0.5-cm diameter glass rods as coarse aggregate. The glass rods were essentially smooth and elongated and adopted a preferred orientation approximately parallel to the base of the concrete prism. Several sections of each concrete prism were made by slicing both at the same angles with respect to this plane of preferred orientation. In the extreme case of long and very smooth glass rods results show that the orientation of the section has an important effect on the average values of the shape and roughness coefficients. When the shape of particles is such that preferred orientation is less apparent these values do not differ significantly for differently oriented sections provided the number of profiles is representative.
Liquid Metal Embrittlement of 4145 Steel by Lead-Tin and Lead-Antimony Alloys
Authors: Breyer NN , Johnson KL 
Published: February 2009

Abstract
Pure lead soldered to the gage section of 200-ksi (1379-MPa) 4145 steel tensile specimens tested at temperatures ranging from room temperature to 700°F (371°C) exhibit a severe loss in ductility between 400 and 680°F (204 and 360°C). The ductility, as measured by reduction of area, recovered at 695°F (368°C), the so-called brittle-to-ductile recovery temperature. This recovery temperature was shifted to higher temperatures in a sensitive manner by relatively small amounts of either tin or antimony added to alloy the externally applied lead.
An Analysis of the Influence of Mean Stress Intensity and Environment on Fatigue Crack Growth in a New High Strength Aluminum Alloy
Authors: Branco CM , Radon JC , Culver LE 
Published: February 2009

AbstractThe effects of the mean stress intensity factor Km and the range of the stress intensity ΔK on fatigue crack propagation during wholly tensile loading cycles in the aluminum (Al) alloy RR58 in laboratory air and in a 3.5% NaCl solution have been studied using contoured double-cantilever beam specimens. In general the fatigue crack growth rate in NaCl solution was greater than in air under similar conditions except for tests in which high values of the maximum stress intensity factor were used when no significant difference was observed.Based on the experimental data a relation between the cyclic crack growth rate da/dN and the tensile loading levels has been proposed. The threshold value of ΔK, ΔKth, is approximately 12% higher in air than in the 3.5% NaCl solution, and its value decreases linearly with increasing values of Km.
Cumulative Fatigue Damage Analysis of a Light Truck Frame
Authors: Mitchell MR , Wetzel RM 
Published: February 2009

Abstract
A case study describes a fatigue damage analysis of a light truck frame. The objective of the analysis is to determine whether an existing frame design can safely accept a 10% increase in load. The analysis, completed in less than a month, incorporates an experimental stress-strain analysis, proving ground test data, and experimentally determined properties of the frame material. Three common methods of damage analysis and a relatively new procedure are compared and the advantages of the new method are demonstrated.
The Effect of Water Content on the Compressive Strength of Laterized Concrete
Authors: Adepegba D 
Published: February 2009

Abstract
Laterized concrete is defined as concrete in which laterite fines replace sand. A previous paper highlighted only the salient points of difference between laterized and normal concrete. The results reported in this paper are mainly on the effect of water content on the compressive strength of laterized concrete. Other properties such as durability, resistance to frost action, and creep need to be investigated to decide whether or not laterized concrete would be usable in all climates. It is the aim of the author that this paper and his earlier paper will generate research interest in other parts of the world where facilities and climatic conditions are more favorable for the investigations of properties which are not easily investigated in the tropics.
The mix design showed that laterized concrete mixes require more water than normal concrete for equal proportions and weights of dry normal concrete and of dry laterized concrete mix. The water/cement ratio recommended for structural laterized concrete mixes of 1:1:2 and 1:1½:3 by weight is 0.65. This water/cement ratio would yield compressive strength of about 23.59 MPa (3425 psi) for 1:1:2 and 21.45 MPa (3110 psi) for 1:1½:3 by weight in 28 days. The water/cement ratio recommended for 1:2:4 mix by weight is 0.75. This would yield about 18.50 MPa (2682 psi) in 28 days.
Graphs showing the variation of compressive strength with water/cement ratio and independently with age are presented.
A schematic map of the world showing laterite deposits is included. It is suggested that the paper may generate interest in reinforced laterized concrete structural elements and that laterized concrete may eventually be used for structural works in those parts of the world where suitable sharp sand is not available, just as lightweight concrete is now being slowly introduced into major construction works.
Variability in Fatigue Crack Growth Rate Testing
Authors: Clark WG , Hudak SJ 
Published: February 2009

Abstract
To provide the data necessary to develop a recommended practice for fatigue crack growth rate testing, an extensive interlaboratory (round robin) program was conducted and the variability and bias associated with the current state of the art of fatigue crack growth rate testing was determined. Fatigue crack growth rate data (expressed in terms of linear elastic fracture mechanics parameters) were generated for a 190-ksi (1310-MPa) yield strength 10 Ni-8Co-1Mo steel at 15 different laboratories with several test specimen geometries. The results were evaluated statistically and on the basis of a graphical comparison, and the variability and bias associated with both the experimental and analytical aspects of crack growth rate testing were determined. In general, the overall interlaboratory variability was found to be approximately 3 to 1 (on crack growth rate at a given stress intensity range). The intralaboratory variability was typically 2 to 1. No significant geometry or data processing bias was encountered. The results of this study show that the primary source of variability associated with fatigue crack growth rate testing is the experimental procedure used to obtain the raw test data (crack length versus elapsed cycles).
Generating River Bottom Profiles with a Dual-Frequency Identification Sonar (DIDSON)
Authors: Maxwell Suzanne L. , Smith April V. 
Published: February 2009

Abstract
Estimating fish passage in rivers with a side-looking sonar positioned near shore requires proper alignment of the transducer with the river bottom. To maximize fish detection, we developed a robust aiming protocol using river bottom profiles generated from standard and long-range dual-frequency identification sonars (DIDSONs). The DIDSON profiles compared well with those generated from range and depth measures or bathymetry methods when the river bottoms were linear or changed from a steeper slope near shore to a flatter slope offshore. If the offshore slope was steeper, the DIDSON profile displayed shallower depths. The actual differences in depth between the DIDSON profiles and those from other methods were often considerably less than the potential differences from beam-spreading error. The maximum depth differences between the same DIDSON profiles marked independently multiple times ranged from 0.08 m for the DIDSON's highest frequency to 0.5 m for the lowest. A model of the fish-counting transducer beam was plotted in the same coordinate system as the river bottom profile. Macros developed for Excel spreadsheets enabled us to “rotate” the beam and determine the optimal tilt angle for each river bottom profile.
Leaf traits capture the effects of land use changes and climate on litter decomposability of grasslands across Europe
Authors: Fortunel Claire , Garnier Eric , Joffre Richard , Kazakou Elena , Quested Helen , Grigulis Karl , Lavorel Sandra , Ansquer Pauline , Castro Helena , Cruz Pablo , DoleŽal JiŘí , Eriksson Ove , Freitas Helena , Golodets Carly , Jouany Claire , Kigel Jaime , Kleyer Michael , Lehsten Veiko , Lepš Jan , Meier Tonia , Pakeman Robin , Papadimitriou Maria , Papanastasis Vasilios P. , Quétier Fabien , Robson Matt , Sternberg Marcelo , Theau Jean-Pierre , Thébault Aurélie , Zarovali Maria 
Published: February 2009

Land use and climate changes induce shifts in plant functional diversity and community structure, thereby modifying ecosystem processes. This is particularly true for litter decomposition, an essential process in the biogeochemical cycles of carbon and nutrients. In this study, we asked whether changes in functional traits of living leaves in response to changes in land use and climate were related to rates of litter potential decomposition, hereafter denoted litter decomposability, across a range of 10 contrasting sites.To disentangle the different control factors on litter decomposition, we conducted a microcosm experiment to determine the decomposability under standard conditions of litters collected in herbaceous communities from Europe and Israel. We tested how environmental factors (disturbance and climate) affected functional traits of living leaves and how these traits then modified litter quality and subsequent litter decomposability.Litter decomposability appeared proximately linked to initial litter quality, with particularly clear negative correlations with lignin‐dependent indices (litter lignin concentration, lignin : nitrogen ratio, and fiber component).Litter quality was directly related to community‐weighted mean traits. Lignin‐dependent indices of litter quality were positively correlated with community‐weighted mean leaf dry matter content (LDMC), and negatively correlated with community‐weighted mean leaf nitrogen concentration (LNC). Consequently, litter decomposability was correlated negatively with community‐weighted mean LDMC, and positively with community‐weighted mean LNC.Environmental factors (disturbance and climate) influenced community‐weighted mean traits. Plant communities experiencing less frequent or less intense disturbance exhibited higher community‐weighted mean LDMC, and therefore higher litter lignin content and slower litter decomposability. LDMC therefore appears as a powerful marker of both changes in land use and of the pace of nutrient cycling across 10 contrasting sites.