bluuebunny/crossref_metadata_2025 huggingface dataset:
Development of a New In-Situ Direct Shear Test
Authors: Matsuoka H , Liu S , Sun D , Nishikata U
Published: February 2009

An in-situ direct shear test apparatus, in both small and large sizes, and its testing techniques have been developed. This test is performed simply by pulling horizontally a latticed shearing frame, embedded in the ground, with a flexible rope or chain under the application of a constant vertical load on the sample. In the new test, the real normal and shear stresses acting on the shear plane can be exactly measured. A number of the large-sized in-situ direct shear tests have been performed on eight kinds of coarse-grained granular materials including rockfills at different construction sites of embankments. The measured shear strengths approximate those of large-sized triaxial compression tests on samples with parallel grain-size distributions. The smaller version of this new test has been used successfully for testing sands and clays. For clays, artificially produced or in-situ, the measured undrained shear strengths are nearly equal to qu/2 by unconfined compression tests on the same clays. The extreme simplicity and high accuracy of this newly developed test are emphasized.
A Comparative Study of Particle Size Analyses by Sieve-Hydrometer and Laser Diffraction Methods
Authors: Wen B , Aydin A , Duzgoren-Aydin NS
Published: February 2009

Combined sieve-hydrometer method (SHM) is one of the two conventional methods commonly used in research and practice in all branches of science and engineering dealing with soils. SHM, however, has some inborn defects, which lead to systematical errors. The paper discusses the major causes of such errors in the analysis with examples from saprolitic soils derived from granites and volcanics. It is concluded that the deviations may be explained by three factors: differences in definitions and measurements of particle sizes; variations in densities of constituent grains; and turbulence in flow pattern of suspension. Particle size distribution (PSD) curves produced by the laser diffraction method (LDM) generally agree with those of SHM. However, some discrepancies between the results of these methods become evident upon closer inspection, and vary in extent according to the soil type and specific size fraction. For the same soil sample and a given fraction, such discrepancies can be mainly attributed to variations in density, shape, and mineralogy of particles. LDM with its many advantages over SHM should be adopted as the standard in geoengineering and geoenvironmental research, particularly involving problematic soils.
Steady State Strength of Sands in a Constant Volume Ring Shear Apparatus
Authors: Garga VK , Infante Sedano J-A
Published: February 2009

A modified volume ring shear test apparatus has been developed to undertake constant volume ring shear tests on sand. This constant volume test is a useful means of assessing the steady state strength of granular soils at large strain to determine the liquefaction potential of a soil mass. The apparatus and specimen preparation tools and methods are presented herein. The paper also presents the device and method used to verify the uniformity of the specimens prepared and the repeatability of the specimen preparation method. An experimental program has been conducted using both constant volume (CV) and constant load (CL) tests to investigate the effect of saturation, and of fines on the steady state line (SSL) and the steady state strength (SSS) envelope.
A Modified Soil-Geosynthetic Interactive Performance Test for Evaluating Deformation Behavior of GRS Structures
Authors: Ketchart K , Wu JTH
Published: February 2009

A modified Soil-Geosynthetic Interactive Performance (SGIP) test apparatus for evaluating short- and long-term deformation behavior of soil-geosynthetic composites was developed. In the test, a specimen of soil-geosynthetic composite, with dimensions of 305 mm wide, 605 mm long, and 305 mm high, was subjected to a vertical sustained load under plane strain condition. The applied load was transferred from the soil to the geosynthetic, and it allowed the soil and geosynthetic to deform in an interactive manner. Lateral and vertical displacements of the test specimen and strains in the reinforcement were measured. A series of the soil-geosynthetic performance tests were conducted to examine test repeatability, failure mode, and deformation behavior of different soil-geosynthetic composites. Test results and discussion of test results are presented. The applicability of the performance test to actual GRS structures was examined by comparing test results with measured behavior of a 5.4-m high GRS pier.
Electromagnetic Wave Propagation Model for Differentiation of Geotechnical Disturbances Along Buried Cables
Authors: Dowding CH , Summers JA , Taflove A , Kath WL
Published: February 2009

The lumped-circuit, hybrid, finite-difference/FFT (fast Fourier transform) model described herein simulates effects of multiple discontinuities in a coaxial cable at variable distances on a time domain reflectometry (TDR) signature. This model is verified by comparison with measured reflections from perfectly defined, multiple deformities. Accurate simulation is an important component of TDR technology as it allows improved calculation of the amount of shearing at multiple locations along special cables grouted in a rock or soil mass.

This paper is arranged in four sections. The introduction or background section presents the need for the model, nature of discontinuities, and the uses of long TDR cables. Design of the hybrid computer model is presented in the following section: Modeling of Coaxial Cable Response. Calculated and field-measured signatures are compared and methods of calibration are introduced in the section entitled: Calibration of Model and Comparison with Field Data. The paper closes with a summary and conclusions.
Variable-Head Field Permeability Tests in Driven Flush-Joint Casings: Physical and Numerical Modeling
Authors: Chapuis RP , Chenaf D
Published: February 2009

Two types of variable-head permeability tests in driven flush-joint casings, the end-of-casing test and the lateral injection test (Lefranc test), were performed in two sand tanks. Hydraulic conditions in the sand tanks included a constant vertical hydraulic gradient that was null, positive, or negative. The gradients were monitored by lateral piezometers, which confirmed that the large-scale hydraulic conductivity (k) value of the sand layer remained constant throughout the test program. Any interpretation method for these variable-head tests implicitly requires an assumed piezometric level (APL) for analysis. According to a common practice, the elevation of the ponded water surface above the sand deposit was taken as the APL to plot the test results as the logarithm of the difference in total head versus time. After each casing installation, permeability tests were performed for the three gradient conditions. When the vertical gradient was null in the tank, the test data provided straight lines as assumed in theory. When the gradient was positive or negative, the test data provided curved graphs that may be interpreted as giving k values that vary with time. The velocity graph method, however, provided the same constant k value for the three gradient conditions. It also detected the error in the APL and provided in all cases a local piezometric level (PL) equal to that given by lateral piezometer monitoring. Thus, the velocity graph method, a graphical representation of the conservation equation, eliminated the potential for misanalysis of variable-head tests. The experimental k values, as determined by the two types of tests, usually ranged between 0.5 and 2 times the larger-scale values determined independently by the monitored flow rates and gradients in the sand tanks. The variability in experimental k values was partly due to the local variations of void ratio and effective diameter of the sand, and partly due to the influence of casing installation. Numerical simulations of the tests confirmed the validity of the velocity graph method for providing k and the local piezometric level for a test.
Resonant Column Testing: The Inherent Counter EMF Effect
Authors: Wang Y-H , Cascante G , Santamarina JC
Published: February 2009

The standard magnet-coil driving system in resonant column devices provides the required cyclic excitation; however, it inherently produces a counter electromotive force that opposes the motion. In this study, the resonant column is modeled as an electro-mechanical system to quantitatively examine the counter electromotive effect and to explore its effect on resonant frequency and damping ratio computed from voltage-based measurements. The model is verified with two independent sets of experiments. Experimental and analytical results show that the measurement bias is more pronounced on the damping ratio than on the resonant frequency, the damping bias is not a device constant but varies with frequency, and the error is particularly relevant in low-loss and low-stiffness specimens (such as dry sands at low confinement). The electro-mechanical model permits developing device-specific correction charts that can be used to reexamine previously published damping ratio data gathered with voltage-based resonant column procedures.
Plane Strain Strength and Deformation of Sands Affected by Batch Variations and Different Apparatus Types
Authors: Yasin SJM , Umetsu K , Tatsuoka F , Arthur JRF , Dunstan T
Published: February 2009

Differences in the strength and deformation characteristics in plane strain compression between different batches of two sand types were critically evaluated. Two types of plane strain apparatuses were used. Large differences were observed between different batches of each type of sand, yet virtually no differences were found in particle physical properties including gradation, specific gravity, minimum and maximum void ratios, particle shape, and crushability. For each type of sand, differences in the measured peak strength between two types of plane strain tests were very small when effects of several possible influencing factors were accounted for. The prepeak dilatancy characteristics were noticeably different between the two types of plane strain tests, but the reason(s) could not be identified. The trend of inherent strength anisotropy was found to be very similar for the two plane strain apparatuses, but did depend on the sand type.
Resilient and Permanent Characteristics of Reinforced Granular Materials by Repeated Load Triaxial Tests
Authors: Moghaddas-Nejad F , Small JC
Published: February 2009

Drained repeated load triaxial compression tests were conducted to investigate the resilient and permanent stress-strain behavior of two granular materials reinforced by a geogrid. In order to obtain more accurate measurement of recoverable deformation, an on-sample measuring method was utilized. Because devices for measuring the axial and lateral deformation are attached to the specimen, the confining pressure is provided by applying a vacuum within the specimen. The effect of a geogrid in reducing the permanent deformation of soils at various combinations of deviator and confining stress is investigated and discussed. The test results indicate that a geogrid can play a significant role in reduction of deformation of the triaxial specimen, and could, therefore, be expected to reduce deformations in the field. However, the results obtained for resilient deformations show that the geogrid does not have a considerable influence on the resilient modulus of the two types of soil (sand and fine gravel) that were tested.
Transmissivity of a Nonwoven Polypropylene Geotextile Under Suction
Authors: Stormont JC , Ray C , Matthew Evans T
Published: February 2009

A permeameter has been developed for measuring in-plane transmissivity of geotextiles under a nearly constant value of suction along its length. The permeameter is capable of imposing gradients in excess of 10% and normal pressure up to 240 kPa, and permits the monitoring of the suctions within the geotextile during testing. To demonstrate the capability of the permeameter, a series of transmissivity measurements were made on a nonwoven polypropylene geotextile subject to different suction heads, normal pressures, and gradients. Transmissivities were up to two orders of magnitude less than the saturated value depending the on the magnitude of the suction head and whether the geotextile was being wetted or dried (hysteresis). Transmissivity values were independent of the gradient for these measurements. Increasing the applied normal pressure decreased the transmissivity at all values of suction head.
An Optical Technique for Investigating Soil Displacement Patterns
Authors: Gill DR , Lehane BM
Published: February 2009

An optical, nonintrusive technique for measuring soil deformation in three-dimensional laboratory scale tests is described. The technique combines the use of a video camera capable of recording the movement of targets to a high resolution, and a transparent porous material possessing geotechnical properties similar to natural clay. The technique is demonstrated in a model test conducted to measure soil deformation patterns around penetrometers. The displacement measurements compare well with results from other published tests and indicate that the technique can provide better resolution than has been previously achieved in similar laboratory tests.
Glass Transition of Asphalts Under Pressure
Authors: Schweyer HE
Published: February 2009

A study was made of the glass transition phenomena on 28 different types of asphalts by means of a simple dilatometric procedure. The study was made over a range of pressures from 1 atm pressure up to approximately 2000 atm in some instances. A study of the pressure susceptibility of the asphalt glass transition temperature demonstrated that there is a linear relationship between the glass transition temperature and the pressure. The slope of this relationship was evaluated as the pressure sensitivity of the asphalt. Data are also presented on the viscosity of certain asphalts at temperatures of 10 to 60°C under 500 atm pressure. From plots of viscosity temperature data the viscosity at the glass transition temperature under 1 atm and 500 atm are compared. It was found for many of the asphalt studies that the viscosity at the glass transition was approximately 109 poises for estimates at both 1 and 500 atm absolute pressures.
High-Temperature Properties of a High-Purity Ferritic Stainless Steel
Authors: Kies FK , Schwartz CD
Published: February 2009

The resistance of Alloy XM-27 to a variety of high-temperature environments was investigated. The alloy was tested in cyclic and semicontinuous oxidation and sulfidizing environments, and the results were compared to conventional, heat resistant alloys. Elevated tensile and stress rupture properties and resistance to embrittlement at 482, 704, and 982°C (900, 1300, and 1800°F) were evaluated.
Soil-Stress Gage Design and Evaluation
Authors: Triandafilidis GE
Published: February 2009

A state-of-the-art review of the various basic types of soil-stress gages available today (1973) is presented. The basic parameters that influence soil-stress measurements as well as the design and evaluation criteria of soil stress gage instrumentation for laboratory and field applications are discussed. Soil-stress gage performance is evaluated in terms of geometry, stiffness, pressure-sensitive and gross gage areas, unit weight, natural frequency, calibration, waterproofing, temperature sensitivity, signal-to-noise ratio, and placement characteristics.
Temperature Influence on Corrosion Fatigue Behavior of 5Ni-Cr-Mo-V Steel
Authors: Ryder JT , Gallagher JP
Published: February 2009

An investigation of the below KIscc corrosion fatigue crack propagation behavior of 5Ni-Cr-Mo-V steel in a 3½ percent NaCl environmental solution is conducted with particular emphasis on the influence of frequency and temperature. The behavior is described using a generalized equation which incorporates the influence of temperature, frequency, and stress intensity range. The generalized equation 1dadN∣C=dadN∣F{H(ΔK,f,T)} relates the corrosion fatigue crack growth rate, dadN∣C, to the baseline cycle-dependent fatigue crack growth rate, dadN∣F. The function H is an environmental enhancement multiple. The severity of the temperature influence on environmentally enhanced fatigue crack growth rates of steels in aqueous environments appears to be related to the inherent resistance of the material to environmental cracking.
Crack Initiation and Growth in Plane Strain, Fully Plastic Zircaloy®
Authors: Kass JN , Begley JA , Andrejasik H
Published: February 2009

A fractographic study of crack extension in plane strain, fully plastic Zircaloy® was conducted. Three specimen geometries were studied: double-edge notched, compact tension, and center notched specimens. Slip line solutions for these geometries predict high, moderate, and no stress elevation, respectively, ahead of the crack tip. These differences might be expected to produce different modes of crack extension. However, crack tip blunting effects were found to overwhelm geometry induced differences. Blunting was found in all three geometries. Stretched zone width was found to be ∼J/σy, or about 0.01 in. (0.254 mm), regardless of geometry. Several variations of blunted crack tip shape were observed for all three specimen types. Two methods of crack extension were observed for all three geometries studied. In the first method ellipsoidal holes were found to nucleate and grow ahead of the main crack tip. Growth continued until the ligament between the main crack and the hole was less than the major axis length of the hole. The hole then joins the main crack by means of local strain instability. The second method consists of alternate sliding off in a zigzag fashion. JIC was measured and found to be equivalent for all three geometries.
Short-Time Creep of Columbium and Tantalum Alloys at 2600 to 3200°F
Authors: Perkins RA , Wright ES
Published: February 2009

Uncoated Ta-17W and C129Y alloys and coated Ta-10W, C103, and C129Y alloys have been evaluated for short-time creep behavior at 2600 to 3200°F. The time for creep strains of up to 2 percent has been measured and the results have been used to derive empirical equations that predict short-time creep life in this temperature range. The equations give estimates of the time-to-creep strains of up to 2 percent at stress levels that will produce the maximum strain in 60 min or less. Silicide-base coatings appear to add to the creep strength of coated Ta-10W but have little added effect on the strength of the columbium-base alloys. The creep behavior of coated metals can be analyzed by the same empirical methods as those used for uncoated substrates. The results show that commercially available silicide coatings protect the substrate from oxidation with creep strains of up to 2 percent on exposures of 1 to 1½ h in this temperature range.
Axial Alignment Fixtures for Tension Tests of Threaded Specimens
Authors: Jones MH , Bubsey RT , Succop G , Brown WF
Published: February 2009

A fixture of simple design is described that is capable of providing very low eccentricity of loading in tension tests of threaded specimens. This fixture is suitable for use with the Method for Screening Tests Using Sharply Notched Cylindrical Specimens proposed by ASTM Committee E-24 on Fracture Testing of Metals. A special ½-in.-diameter (12.7-mm-diameter) evaluation specimen and associated procedure is described which is useful for determining the maximum bending that might be encountered in routine use of the fixture. The results obtained using this technique show that the maximum bending stress can be reliably limited to less than five percent of the average axial stress for an axial stress equal to or greater than 30 ksi (207 MPa) on the evaluation specimen. This evaluation technique is also suitable for verification of the satisfactory performance of other types of fixtures intended for use in the tension testing of sharply notched cylindrical specimens.
Decreasing the Fatigue Strength Reduction Factor by Dimpling
Authors: Shewchuk J
Published: February 2009

A new approach to decreasing the fatigue strength reduction factor of holes in ductile sheet metallic material is presented. The material is first stretched by dimpling centering about the region where the hole is to be made. Subsequent flattening of the material creates residual compressive stresses in the dimple region. The hole is then drilled leaving the peripheral material in a state of compressive stress.

Zero-to-tension fatigue tests on nominally 0.050-in. (1.27-mm) thick 2024-T3 alclad aluminum alloy specimens show a 36 percent decrease in the fatigue strength reduction factor by dimpling for 106 cycles to failure.
Signal Processing in Nondestructive Testing
Authors: Kennedy JC , Woodmansee WE
Published: February 2009

Signal averaging has been used to improve the clarity of flaw indications in an electron beam weld. The delay of an electronic gate has been synchronized to the transducer motion to improve the detectability of a tight interface crack in a tensile specimen. Cross-correlation techniques and multiple transducer arrays have been used to improve the signal-to-noise ratio of artificial flaws in welded panels. Signal averaging has been used to reduce random noise in the through-transmission ultrasonic inspection of a honeycomb composite. Megacycle range ultrasonic flaw information has been recorded on a low frequency FM tape recorder by rapidly sweeping an electronic gate through the time interval of interest. A lock-in amplifier has been used to produce quantitative data in both single-coil and double-coil eddy current systems. Cross-correlation techniques and a multiple-coil eddy current probe have been used to reduce surface roughness noise in an eddy current crack detection system.
Properties of 713LC Compacts, Hot Isostatically Pressed at Supersolidus Temperatures
Authors: Wallace W , Holt RT , Whelan EP
Published: February 2009

Nickel-base superalloy (713LC) powders produced by two techniques have been consolidated by a single-stage, hot isostatic pressing operation to obtain fully dense, coarse-grained (ASTM 1-2) material. After heat treatment the compacts produced by powder from the rotating electrode process gave tensile strengths between 95 and 112% of that of the as-cast alloy, and stress rupture lifetimes at 980°C and 152 N/mm2 of between 30 and 63% of the as-cast alloy. Compacts produced from argon-atomized powder were heat-treated to give better 760°C stress rupture strengths than cast 713LC. The tensile and stress rupture ductilities of these compacts were generally lower than those of equivalent cast material. At low temperature the ductility is limited by grain boundary precipitates of carbides and sulfocarbides, and at high temperature (980°C) interstitial elements and impurity elements in solid solution are thought to give rise to grain boundary embrittlement. The relationships between microstructure, mechanical properties, and fracture behavior are examined, and the limitations of supersolidus treatment of these alloys are discussed.
The Measurement of the Coefficient of Friction of Polymer Pellets Under Extruder Conditions
Authors: Evans RE
Published: February 2009

A modification of a friction and wear test apparatus is described which permits measurement of the coefficient of friction (COF) of polymer pellets at conditions comparable to those in the solids feed section of an extruder. A specimen holder containing three pellet-filled cylinders is rotated against a stationary plate under prescribed conditions; the effects of pressure, velocity, temperature, roughness, and surface cleanliness can be investigated. The device is connected to an electronic load cell and recorder so that a continuous record of COF versus time is obtained. The utility of the apparatus is demonstrated by measuring the change in the COF of thermoplastic pellets as a function of several test parameters.
A New Method for Determination of Proportional Limit and Machine Stiffness
Authors: Clough RB
Published: February 2009

A new method for determining the proportional limit of engineering materials, characterized by maximum stress rate, is presented. Simultaneous measurement of stress rate and strain rate also permits a new means of measuring machine stiffness which has certain advantages over present techniques.
Acoustic Emission Testing of Unflawed 7075-T6 Aluminum
Authors: Hamstad MA , Mukherjee AK
Published: February 2009

Tensile tests were performed to study the differences in the continuous acoustic emission from 7075-T6 aluminum plates made by five manufacturers. The grain structures and the chemical compositions of these plates were determined. Results are given on a sixth plate, which emitted burst-type acoustic emission super-imposed on the continuous acoustic emission. The effect of orientation with respect to the rolling direction within a single plate was studied. Results from interrupted tensile tests are also reported; these tests were stopped at about 4.5% strain for different time periods before they were resumed. The tests indicate that acoustic emission is very sensitive to differences between plates of 7075-T6 aluminum that do not show up on a stress-strain curve. Furthermore, the dislocation mechanisms that cause the continuous acoustic emission in this aluminum alloy are altered by room temperature, diffusion-based aging.
Fracture Testing with Surface Crack Specimens
Authors: Orange TW
Published: February 2009

This paper is a report of ASTM Task Group E24.01.05 on Part-Through Crack Testing. It includes recommendations for the design, preparation, and static fracture testing of surface crack specimens based on the current state of the art. The recommendations are preceded by background information including discussions of stress intensity factors, crack opening displacements, and fracture toughness values associated with surface crack specimens. Cyclic-load and sustained-load tests are discussed briefly. Recommendations for further research are included.
A Technique for Examining Submicron Particulate Matter on Semiconductor Device Wafers
Authors: Berenbaum L
Published: February 2009

A technique is described for locating and consequently removing submicron particulate matter from semiconductor device wafers. Chemical and structural analyses of these particulates are obtained from energy dispersive X-ray spectra and selected area electron diffraction patterns, respectively.
A Review of Aggregate Selection Criteria for Improved Wear Resistance and Skid Resistance of Bituminous Surfaces
Authors: Dahir SH
Published: February 2009

This paper includes a summary of an extensive literature review and the experience of the author in researching the properties of surface aggregates. It confirms that to resist wear, the aggregate must be hard and tough, and to resist polishing and surface slipperiness, the aggregate must wear slowly and irregularly. Particle shape, size, and gradation are important characteristics in providing optimum pavement surfaces, but ultimate aggregate performance depends largely on the aggregate mineralogy. A high proportion of hard minerals well cemented in a softer or a porous matrix will provide both high skid resistance and acceptable wear resistance. Within an aggregate particle, grain shape and size contribute to improved performance—medium to large and angular to subangular crystalline grains outperform minute and rounded non-crystalline grains. The performance history of an aggregate provides the best key to its expected future performance. In the absence of experience with an aggregate or when it is to meet new requirements, commonly used tests combined with petrographic analysis should provide sufficiently dependable initial information on the expected aggregate performance. A table that includes suggested target values for properties that enhance aggregate skid resistance and wear resistance is included in the paper.
Application of Computer Techniques to Charpy Impact Testing of Irradiated Pressure Vessel Steels
Authors: Landow MP , Fromm EO , Perrin JS
Published: February 2009

A Rockwell AIM 65 microcomputer has been modified to control a remote Charpy V-notch impact test machine. The computer controls not only handling and testing of the specimen but also transference and storage of instrumented Charpy test data. A system of electrical solenoid activated pneumatic cylinders and switches provides the interface between the computer and the test apparatus. A command language has been designated that allows the operator to command checkout, test procedure, and data storage via the computer. Automatic compliance with ASTM test procedures is built into the program.
Holographic Examination of a Composite Pressure Vessel
Authors: Meyer MD , Katayanagi TE
Published: February 2009

We have examined a composite pressure vessel using holographic interferometry. Interference patterns obtained from an internal pressure change show that there is an area of high shear strain in the knuckle area of the vessel that seems to correspond to the area of premature failure. We make several suggestions aimed at reducing the shear stress in the knuckle area.
Fatigue Damage: Stiffness/Strength Comparisons for Composite Materials
Authors: O'Brien TK , Reifsnider KL
Published: February 2009

Boron/epoxy laminates in a [0-deg/ + 45-deg/ - 45-deg/ 0-deg/0-deg/ + 45 -deg/ - 45-deg/0-deg] layup were tested statically for initial strength and fracture strain and were tested in strain-controlled fatigue loading at 30 Hz, with a strain-amplitude ratio of one tenth for five different testing sequences.

A reduced stiffness analysis was used in conjunction with laminated plate theory to predict stiffness changes based on observed debonding and fiber breakage. Specimens used for strength analysis either fractured during fatigue or were loaded statically to failure after fatigue. All specimens were leached with a heated acid, and fiber breakage was recorded. Correlations are noted between matrix damage and stiffness changes as well as between fiber breakage and strength reduction.
A Study of Durability in Temperature Cycles and Water Resistance of Sulfur Concretes and Mortars
Authors: Shrive NG , Gillott JE , Jordaan IJ , Loov RE
Published: February 2009

The durability of sulfur concretes and mortars in expected-use environments is considered. The effects of temperature cycling and immersion in water are considered separately, and the effects of temperature, specimen size, and mold material on the strength of these materials are also discussed. The problem of biological attack is not considered. Immersion in water of specimens containing swelling clays can cause disintegration of sulfur concretes and mortars in a short time. Attempts to solve the problem caused by the presence of swelling clay are described. Partial success was obtained. The results of independent tests on the effects of water and temperature cycling should be considered before the result of freezethaw tests on sulfur concretes and mortars are interpreted. Erratum to this paper appear in 6(2).
Cooperative Plane Strain Fracture Toughness Tests with C-Shaped Specimens
Authors: Underwood JH , Kendall DP
Published: February 2009

The results of a cooperative test program on plane strain fracture toughness (KIc) testing with C-shaped specimens are reported and discussed. Results of 48 tests by eight laboratories using specimens with two different loading hole locations are included. The effects of specimen geometric variables, such as eccentricity of the inner and outer surfaces and nonperpendicularity of these surfaces with the specimen faces, on the measured and calculated KIc are discussed. The C-shaped specimen results are compared with measured KIc values obtained with standard compact specimens. Results show that both versions of the C-shaped specimen yield accurate values of measured KIc. Normal geometric variations, as would be expected from machining of the specimen from an existing hollow cylinder, have no significant effect on the measured KIc.
Stress Analysis from Temperature Data
Authors: Jordan EH , Sandor BI
Published: February 2009

A measurement system for monitoring temperature change during mechanical deformation is described. The system is based on thermocouples welded directly to the specimen and is capable of distinguishing temperatures smaller than 0.1°C with a response time less than 0.01 s. An equation to relate temperature change to mechanical variables is stated and experimentally verified. The scalar quantity temperature can be used in stress analysis to determine other scalar quantities related to stress or both stress and plastic strain. Three methods are proposed for analyzing temperature data. The methods are discussed in terms of the basic equation and are experimentally verified. A key element in these methods is the use of rapid loading and rapid data collection that results in data not appreciably altered by heat conduction. Collectively these methods can be used to detect plastic strains as small as 0.0003 m/m in mild steel, to determine magnitudes of specific plastic work, and to determine pressure for elastic deformation. This paper discusses the theoretical and experimental foundations for techniques potentially useful to the study of notched members.
Fracture Toughness Evaluation of Polymers with Surface-Crack Specimens
Authors: Mai YW
Published: February 2009

The use of surface-crack specimens subjected to tension and bending loads for the fracture toughness evaluation of two typical polymers, polypropylene and polystyrene, is described. Experimental results are discussed with particular reference to various correction factors such as slow growth, finite width, back face, crazing, and yielding. Fracture toughness values are also given for two grades of polystyrene of different molecular weights in the temperature range −160 to +40°C.
The Development of a Closed-Loop, Servo-Hydraulic Test System for Direct Stress Monotonic and Cyclic Crack Propagation Studies Under Biaxial Loading
Authors: Charvat IMH , Garrett GG
Published: February 2009

A rig with two orthogonal, servo-hydraulic actuators based around a universal testing machine provides a flexible, low-cost biaxial testing facility and has been used to examine the influence of direct biaxial stress on deformation and crack propagation, particularly in high cycle fatigue. In principle, a balanced, horizontal loading axis is supported independently of the specimen, coincident with its axis, on low-stiffness springs to accommodate the vertical movements of the horizontal loading train; vertical and horizontal force variations, including inertial effects, are negligibly small. For 0 to 50 kN equibiaxial fatigue loading on 6-mm steel plate specimens containing center cracks up to 35 mm in length, a frequency response in excess of 20 Hz was obtained from a single 45 litre/min hydraulic pump. The paper discusses problems encountered in design and operation and recommends further improvements. Finite element stress analysis was used to help derive a cruciform geometry specimen adaptable to compressive and through-zero loading with a satisfactory biaxial stress field over the center section. Fatigue tests on mild steel plate indicated the significant role of specimen geometry in biaxial crack growth studies and showed a decrease in crack growth rate in equibiaxial tension compared with uniaxial tests but a substantial increase during Mode II loading (pure shear, or equibiaxial tension-compression). For angled crack studies tensile crack opening displacements during biaxial crack growth result in rotational relative movement of the two loading axes, which obviate the use of fixed axis systems because of imposed constraints.
A Single Specimen Determination ofJIc for Different Alloy Steels
Authors: Takahashi H , Khan MA , Suzuki M
Published: February 2009

A simplified JIc test procedure has been proposed for determining JIc experimentally from a single specimen. The experimental results have shown that the crack initiation property directly influences the crack propagation behavior of the materials. Measurement of a critical J value corresponding to a small finite amount of crack growth instead of to an assumed blunting line procedure is proposed.
Galvanic Corrosion of Piping and Fitting Alloys in Sulfide-Modified Seawater
Authors: Hack HP
Published: February 2009

Two wrought piping alloys, 70-30 and 90-10 coppernickel, were each galvanically coupled to each of four fitting alloys in sulfide-modified seawater for 30 days. The fitting alloys used were bronze (Composition M), cast Monel®, wrought nickel-aluminum bronze, and cast 70-30 copper-nickel. The piping material to fitting material area ratio was 3:1 and the seawater velocity was 2.4 m/s. Results indicated that the galvanic relationship between M-bronze or Monel and 70-30 copper-nickel is affected by sulfide additions, in a manner that increases the corrosion of the fitting material, whereas similar couples with 90-10 copper-nickel show little effect of sulfide.
The Effect of Oxygen, Salt Concentration, and pH on Galvanic Cells Between a Carbon Filled Polyethylene Cathode and Various Metal Anodes
Authors: Schick G
Published: February 2009

Laboratory experimental techniques are described for the study of galvanic corrosion between carbon black filled polyethylene cathode and galvanized steel, stainless steel, copper, tinned copper, and lead anodes. The environmental variables include 0.001N to 1.0N sodium chloride and sodium sulfate solutions in air-containing and deaerated conditions. Experiments in 1N sodium chloride, adjusted with hydrochloric acid or sodium hydroxide, show the behavior of the above galvanic cells in the 2.5 to 10.5 pH range. Corrosion current densities derived from polarization diagrams for the galvanic couples are presented to demonstrate the effectiveness of the experimental technique.
Void Content Prediction in Two-Size Aggregate Mixes
Authors: Al-Jarallah M , Tons E
Published: February 2009

The purpose of this research was to develop a method to predict the interparticle voids in combinations of two sizes of aggregates. Theoretical concepts and predictions preceded the experimental work. Statistical techniques and computers were used in the design of the experiment and in the analysis of the data. Graphical presentations and illustrations were also used. The experimental work involved three types of rocks having different geometrical properties. Eight differently sized fractions of each of the three types of aggregates were tested. On the basis of the data collected and analyzed, it was concluded that two-size aggregate mixes that have the same size ratio and equal total packing volumes and that were compacted under identical conditions should have the same interparticle packing void contents. The data collected from the experiments were used to introduce a new method (graphical and analytical) to predict the packing void content in two-size aggregate mixes blended at any ratio. The developed blending design curves covered size ratios ranging between 0.20 and about 0.40. Only the percentage of the two constituents in the mix and the size ratio are needed to predict the packing void content by this new method.
A Fracture Mechanics Method for Determining the Crack Propagation Resistance of Embrittled Aluminum Bicrystals
Authors: Kargol JA , Albright DL
Published: February 2009

A fracture mechanics testing method has been adapted to the study of the crack propagation resistance of high purity aluminum bicrystals which fail under liquid metal embrittlement conditions. The tapered double cantilever beam fracture test makes it possible to determine the threshold crack extension force for a propagating crack and the crack velocity as a function of driving force above this threshold. Modifications of this test have been made so that it can be used to determine GILME and crack velocity for 99.99+% pure aluminum bicrystals in a Hg-3 a/o Ga atmosphere. The test is shown to be reproducible, and variations in GILME due to differences in crystallographic orientation of the bicrystals are attainable.
The Effects of Specimen Thickness and Stress Relief on Fatigue Crack Growth Rate in Nickel-Chromium-Molybdenum-Vanadium Steel
Authors: Sullivan AM , Crooker TW
Published: February 2009

Structural design now incorporates the weight-saving advantage of high-strength alloys by reducing the thickness requirements of load-bearing members. For fail-safe applications of thin-section material [less than 0.50 in. (12.7 mm) thick] in high-performance ship structures, quantitative information concerning fatigue crack growth rate (FCGR) is highly important. The paucity and diverse conclusions of presently available information concerning the effect of material thickness on FCGR provides little engineering guidance for the design of thin-section structures. This study of FCGR on a 5Ni-Cr-Mo-V steel tested in three thicknesses indicates that internal residual stresses may have a retardation effect on FCGR in this material. When the material was tested after stress relief, crack growth was accelerated and was essentially the same for all thicknesses.
Multiaxial Stress-Strain Approximations for Notch Fatigue Behaviors
Authors: Walker EK
Published: February 2009

The use of the fatigue notch factor Kf in Neuber's rule is shown to be identical in the elastic range to the assumption of the Hookian stress concentration factor Kt, a multiaxial stress state, and a maximum principal strain criterion for fatigue life. The adequacy of assuming the fatigue notch factor Kf is demonstrated for mild notches. Arguments are presented in favor of assuming a multiaxial stress state at the notch for highly constrained notches.
Respirable Fraction of Airborne Dust: Quantitative Descriptions, Formal Definitions, and Performance Characteristics of Samplers Matched to Them
Authors: Mercer TT
Published: February 2009

A rational system for monitoring atmospheres suspected of containing insoluble toxic particles requires a method that will provide a sample in which all particles are represented in proportion to their “respirable fraction,” that is, in proportion to the probability that they would be deposited in the nonciliated region of the lung, if inhaled by an average man. Various organizations concerned with occupational health have advanced formal definitions of respirable fraction, and samplers operating in accordance with those definitions are widely used for both personal and general area monitoring. In this discussion, quantitative descriptions of respirable fraction, the formal definitions derived from them, and the performance characteristics of respirable fraction samplers are reviewed. The samplers are shown to perform adequately for their respective definitions, but in general the definitions themselves significantly overestimate respirable fraction as determined from recent experimental data.
Effects of Dispersion and Swelling on Soil Hydraulic Conductivity
Authors: Frenkel H , Rhoades JD
Published: February 2009

The mechanisms of clay mineral dispersion and swelling, their effects on soil hydraulic conductivity, and their relevance to piping failures of earth-filled dams are discussed. It is concluded that clay dispersion could initiate piping failures of earthen dams. A method is recommended for evaluating the susceptibility of soil materials to disperse.
Field and Laboratory Protocols for Evaluating the Effects of Chemical Substances on Aquatic Life
Authors: Cairns J , Dickson KL
Published: February 2009

One of the difficulties of evaluating the hazard associated with the release of a chemical substance into the environment is to determine how much testing is necessary to delimit its effects adequately. Since different classes of toxicants have different biological effects, it would be wasteful of both time and money to carry out extremely detailed and comprehensive tests for even the most innocuous materials. It would be equally inappropriate to carry out limited tests for very dangerous materials—as painful experience has already shown. Protocols to sort out which materials require extensive testing and which do not, as well as which decision criteria should be used at each stage in a test series, are essential to the establishment of reasonable water quality standards. This is true not only for laboratory studies but also for assessments of effects in the receiving system itself. Two illustrative protocols, one for the laboratory studies of aquatic organisms and the other for field studies in freshwater receiving systems, are described.
Holographic Interferometry Study of Chemical Bond of Concrete to Smooth Steel Rods
Authors: Nathan SS , Mehta SD , Selvarajan A
Published: February 2009

A method has been proposed to study the characteristics of bond between steel and concrete. The method involves a bond pullout test and holographic interferometry and is suitable for investigating the two stages of bond, adhesive and frictional.
A Procedure for the Determination of Ductile Fracture Toughness Values Using J Integral Techniques
Authors: Clarke GA , Andrews WR , Begley JA , Donald JK , Embley GT , Landes JD , McCabe DE , Underwood JH
Published: February 2009

A procedure to determine the ductile fracture toughness value JIc, the value of the J integral at incipient crack growth, is described. The procedure was developed by the working committee of ASTM Task Group E24.01.09 on Elastic-Plastic Fracture under Committee E-24 on Fracture Testing. The principal goal of this report is to present a procedure for JIc determination that may be used as a basis for an ASTM standard on elastic-plastic testing. Although this procedure is described in terms of the multiple-specimen technique, any single-specimen method can be used as long as a good correspondence exists between the crack extension as measured by the heat tinting technique and that measured by single-specimen methods.
Constant and Variable Amplitude Fatigue Behavior of Eight Steels
Authors: Stephens RI , Benner PH , Mauritzson G , Tindall GW
Published: February 2009

Room temperature fatigue behavior was obtained for eight different steels, including cast, hot-rolled, quenched and tempered, and case-hardened steels, under both constant and variable amplitude load conditions. Constant amplitude fatigue crack growth behavior was obtained with compact-type specimens with load ratios R ≈ 0 and −1. Variable amplitude fatigue behavior was obtained from keyhole-notched compact-type specimens by using the Society of Automotive Engineers' transmission history and three modifications of this history including single tensile overloads. The keyhole specimen and the variable amplitude spectra were chosen to simulate room temperature real-life situations including both crack initiation and crack propagation. Fatigue behavior of the eight steels is compared.
Comments on Erosion Tests Conducted in an ASTM Interlaboratory Test Program
Authors: Steller K , Reymann Z , Targan M , Hammitt FG
Published: February 2009

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.