bluuebunny/crossref_metadata_2025_split huggingface dataset:
Apparatus and Techniques for Static Triaxial Testing of Ballast
Authors: Alva-Hurtado JE , McMahon DR , Stewart HE 
Published: March 2009

Railroad tracks are constructed on a layer of ballast overlying the roadbed subgrade. The ballast is a coarse-aggregate-sized, noncohesive, granular material with angular particles and usually with a uniform gradation.
In order to evaluate the geotechnical performance of railroad tracks, representative stress-strain-volume change and strength properties of the ballast are needed. Because ballast consists primarily of large [up to 76.2 mm (3-in.)] angular particles, conventional triaxial testing equipment is not appropriate. Therefore a large triaxial cell was designed and constructed. The apparatus used in the static ballast testing, and the sample preparation techniques developed, are presented.
Triaxial compression test results on the granite ballast for two different density states are shown. Mohr-Coulomb strength parameters are presented, and the typical stress-strain-volume change behavior is shown. The hyperbolic parameters calculated from the static tests are also shown.
The static test results using the new apparatus and sample preparation techniques indicate that railroad ballast possesses many characteristics common to granular materials.
Lateral Stress Measurements in Direct Simple Shear Device
Authors: Dyvik R , Zimmie TF , Floess CHL 
Published: March 2009

Monitoring lateral stresses in a soil specimen during monotonic or cyclic shear tests significantly increases the amount of information obtained from these tests. A technique is described for interpreting lateral stress data during consolidation (the initial phase of either type of shear test) and determining the lateral stress level at the start of the shear test. In addition, the coefficient of lateral earth pressure at rest (K0) is determined.
The Norwegian Geotechnical Institute (NGI) Direct Simple Shear Device was used in this study. Lateral stress measurements were made with calibrated wire-reinforced membranes (acting as strain gages).
Two undisturbed samples of soft marine clay were investigated: a Gulf of Mexico and a Gulf of Alaska sample. The samples were obtained from a depth of about one metre below the sea floor. Large vertical specimen strains were encountered even though the applied consolidation stresses were small (a maximum vertical stress of 0.518 kg/cm2). The technique described includes methods for eliminating possible sources of substantial error at these low stress levels. The values of K0 as determined from the lateral stress measurements agree well with values determined indirectly.
Borehole Shear Test in Geotechnical Investigations
Authors: Lutenegger AJ , Hallberg GR 
Published: March 2009

The concept of Borehole Shear presents a unique alternative in shear strength testing of soil and rock in that tests may be conducted rapidly on the sides of the hole on relatively undisturbed material; therefore the inherent problems associated with obtaining equivalent information from laboratory tests are eliminated. In contrast to other methods of measuring in situ shear strength (that is, vane shear, cone penetrometer and pressuremeter) the Borehole Shear Test (BST) and Rock Borehold Shear Test (RBST) give discrete values of friction angle and cohesion; therefore more complete analyses may be made for such fundamental problems as bearing capacity and slope stability. In the past the BST has been considered a drained test and the effective parameters φ' and c' have been reported. This may not always be the case.
The general use, operation, assumptions, and problems of the test are examined and examples of the interpretation of results are given. Because of the time, economics, and accuracy of this method, the technique of Borehole Shear should see increased use in future in situ geotechnical testing.
Modified Leach Test Incorporating an Elutriation Step for the Evaluation of Metal Sludges
Authors: Penland JL , Steward FA , Lancy LE 
Published: March 2009

This study is limited to the evaluation of the toxic metal released from metal finishing sludges, combustion ashes, and the solid residuals from atmospheric dust collection systems in a landfill. When leach testing these wastes to establish the potential magnitude of the leachable metals, it has been found that the solid waste also usually contains readily soluble inorganic salts that could affect the leach results. The sludge cake usually contains only interstitial water. Evidently, the volume of the residual water and its salt content is a relatively small quantity. Slurries contain considerably more water, but the total salt content is still most often insignificant. The mix can be quite different if the treatment preceding the solids removal has utilized high-temperature processes, or has aimed to separate the solids by partial or total evaporation of the water. The ashes from combustion or the dust collected from atmospheric separation may not have been subjected to a water quench or washing; therefore, the soluble salts never have been separated. Depending on the volume of these salts when deposited in a landfill, they could by themselves cause a significant deterioration of the groundwater, surface waters, or the land. Therefore, a leach test method that would also reveal abnormal salt concentrations in the waste could fulfill an additional important function.
Washing the solids with water will remove most of these easily soluble solids from the waste, leading to a more dependable and repeatable test condition for a subsequent leach test. The wash waters, if separately collected and tested, will provide insight into the magnitude of the soluble salt content of the solids. Following this logic, a distinction can be made regarding the short-term leach results (wash water) and subsequently, based on a 24-h leach test, the long-term leachability of the solids.
Development of Realistic Tests for Effects and Exposures of Solid Wastes
Authors: Daniels SL 
Published: March 2009

Realistic standard methods are needed by both the regulatory agencies and the regulated communities to measure parameters for evaluating the degree of hazard of solid wastes and the degree of control of proper management techniques. Current regulations issued under the Resource Conservation and Recovery Act (RCRA) contain nonconsensus testing procedures for four characteristics of hazard and determinations of certain species in solid wastes.
Petition may be made for an equivalent testing method. The American Society for Testing and materials (ASTM) is currently developing an equivalent standard method to the U.S. Environmental Protection Agency (EPA) extraction procedure. Petition also may be made to exclude a specific waste produced at a particular facility if listing is found to be inappropriate. ASTM is presently active in providing standard methods for obtaining data for delisting. Standard methods also are needed for measuring the containment of wastes in tanks; the migration of constituents from impoundments, landfills, and landfarms; the destruction and removal efficiency in incineration processes; and the extent of conversion of hazardous constituents in physical, chemical, and biological treatment processes. Demonstration of equivalent performance for these processes for storage, treatment, and disposal of solid wastes using standard methods is a third area of ASTM involvement.
There are two parallel activities involving standard methods: the development of realistic standard methods for measuring effects and exposures of solid wastes; and the evaluation of reproducible results to establish regulatory limits on hazardous constituents and performance guidelines for waste management facilities. The development of realistic tests for effects and exposures of solid wastes is within the province of ASTM. Such tests must also include consideration of toxicity, partition, and fate of hazardous constituents. The evaluation of results is the joint responsibility of the regulatory agency and the regulated community.
Investigation of Surfaces of Retrieved Endosseous Dental Implants of Commercially Pure Titanium
Authors: Brunski JB , Moccia AF , Pollack SR , Korostoff E , Trachtenberg D 
Published: March 2009

Previous work has shown that the interfacial tissue response to pure titanium endosseous blade-vent dental implants in dogs can be influenced strongly by the biomechanical use of the implant. The surfaces of all 16 implants retrieved from our previous study were examined in an effort to evaluate (1) the response of the implant biomaterial to in vivo conditions and (2) the nature of any tissues which attached to implant surfaces. Implants were implanted for two, four, six and twelve months.
No evidence of corrosion or release of titanium in adjacent tissues was observed. Implants did show bone and epithelial tissue attachment to the surfaces, but the quantity of such tissues was usually very small. Although functional versus nonfunctional implants in our previous research produced completely different interfaces, as seen in histology done after removal of implants from the tissues, the present work revealed no correlation between these interface structures and the tissue remnants which were scattered over tiny portions of the implant surface area.
While the data from this study indicate the corrosion resistance of pure titanium in a dental implant application, the implant material plus several additional factors must be considered together in interpreting the total interfacial tissue response to a dental implant.
Low-Velocity Impact Tests on Fibrous Composite Sandwich Structures
Authors: Sharma AV 
Published: March 2009

An experimental investigation was conducted to assess the damage tolerance of composite sandwich structures subjected to low-velocity projectile impact. Sandwich-type specimens fabricated with graphite/epoxy materials having laminate configurations such as (±45,04)s, (±45,90,0)s, and (90, ±45,0)s were tested. Impact tests were performed at low energy levels to assess the strength degradation of composite laminates when compared with their ultimate strengths. Low-energy projectile impact was considered to simulate typically the damage caused by runway debris and the accidental dropping of hand tools during servicing and other similar objects on secondary aircraft structures fabricated with composites. The preload and impact energy combination necessary to cause catastrophic failure was determined. The residual strength of specimens that survived the impact damage was also measured.
Based on the experimental results, a faired curve indicating the lower bound of the failure threshold for each of the laminate configurations tested in compression and tension as a function of the projectile impact energy is shown. Further, the strength degradation due to impact is found to be dependent on the laminate configuration and the fiber/matrix combination.
Sulfur Measurement in Liquid and Gaseous Alternative Fuels
Authors: Kimbell CL 
Published: March 2009

This paper describes sampling systems, analyzers, and analysis procedures developed for measurement of the sulfur content in alternative fuels. Alternative fuels are here defined as any fuel other than coal, oil, natural gas, or liquid petroleum gas. The object of the work described here is to determine the hydrogen sulfide (H2S) and total sulfur content of various fuels. Particular emphasis is placed on determining whether substances present in the alternative fuel might interfere in sulfur measurement, causing loss of accuracy when a test method used to measure sulfur in conventional fuels is applied to alternative fuels.
The equipment described in this study consists of a total sulfur analyzer with a pyrolysis furnace, used in the reductive mode, to convert all sulfurs to H2S. An H2S analyzer operating on the principle of colorimetric change of a lead-acetate-sensing surface, with rateometric readout, is used for H2S analysis. When coupled with the hydrogenolysis furnace, a readout in terms of total sulfur results.
Successful testing of raw shale oil, as well as of refined products from shale oil, was accomplished. The results correlate well with X-ray analysis at high sulfur concentrations in raw shale oil and for refined products of Jet A turbine fuel.
The accuracy between laboratories was within 40 ppb.
Bird Dispersal Recordings: An Overview
Authors: Schmidt RH , Johnson RJ 
Published: March 2009

Bird damage control often involves dispersing birds from areas where they cause problems. Dispersal techniques have been used at airfields, rural and urban bird roosts, livestock facilities, fruit orchards, grain fields, and other locations. Certain avian vocalizations have evolved as alarm or distress calls, and these calls can be exploited as a means of dispersing birds. The behavioral response to such calls, however, varies. Certain species may disperse with the appropriate call, whereas others show little or no reaction. The efficacy of this technique is not well documented at present, but its potential for development as a management tool seems great.
Visual warning signals may increase the effectiveness of bird dispersal recordings by decreasing the habituation rate, increasing realism, or decreasing the fright threshold of the birds causing problems, or by a combination of these factors. Habitat manipulation, which reduces the attractiveness of an area to birds, complements dispersal efforts. It appears that a combination of management techniques is the most effective strategy. In addition, pretreatment evaluation of the problem and situation plus records of field results are helpful parts of a dispersal effort.
Evolutionary, theoretical, and applied aspects of bird communication are discussed as they relate to bird dispersal, the repellency of recorded sounds, habituation rate, and effects of regional dialects. A review of the vocalization and hearing ranges of birds is included; this may help define the frequency and type of sounds most likely to disperse birds. The characteristics of recording and broadcasting equipment are detailed in relation to component selection, and suggestions are made for effective use. A section on field application of bird dispersal recordings provides guidelines for duration and spacing of playbacks and recommends using an integrated approach. Continued refinement of bird dispersal recordings and associated techniques can increase considerably our effectiveness in solving bird damage problems.
New Concepts and Discoveries Related to the Strength Characteristics of Plasticized Sulfur
Authors: Gannon CR , Wombles RH , Hettinger WP , Watkins WD 
Published: March 2009

The objective of this study was to determine the physical reasons for the high-strength characteristics of plasticized sulfur concrete and to define practical manufacturing techniques.
The results of this study reveal some very interesting phenomena. The Vroom process of sulfur plasticization exhibits a very unusual display of ordered angular crystallization. The Bureau of Mines' plasticized sulfur shows a different crystallization pattern consisting of bonded spherical bodies. These crystallization phenomena indicate a logical physical explanation for the superior strength characteristics inherent in plasticized sulfur concretes manufactured by entirely different processes. These new discoveries are revealed by microscopic examinations utilizing both the stereomicroscope and the scanning electron microscope. These unique microscopic phenomena offer to the scientific community a different explanation as to why unusually higher strengths are obtained in plasticized sulfur concretes. Classical chemical and physical concepts concerning properties of plasticized sulfurs are complemented by factual microscopy. Practical methods of manufacturing sulfur concretes have been defined.
Prediction of Long-Term Failure in Kevlar 49 Composites
Authors: Gerstle FP , Kunz SC 
Published: March 2009

Creep rupture data in Kevlar 49 epoxy usually exhibit considerable scatter: the coefficient of variation (CV) about the mean failure time at a given stress often exceeds 100%. In this paper, analysis of existing creep rupture data on Kevlar epoxy vessels at four storage pressures has produced an interesting and useful result. It was found that a significant portion of the scatter in failure times for pressure vessels is due to spool-to-spool variation in the eight spools of Kevlar fibers used to wind the vessels. The rank order of mean times to failure was consistent over a pressure range from 23.4 to 29.7 MPa (3.4 to 4.3 ksi), 68 to 86% of short-term burst. Also, the coefficient of variation about the mean failure time for each spool was less than that for the total sample. The statistical inference that the sample is nonhomogeneous was supported by a nonparametric check using the Kruskal-Wallis test and by a parametric analysis of variance. The rank order found in long-term tests did not unequivocally agree with static strength ranks; several spool sets were distinctly high or low. The implication is that, while static strengths are not valid predictors of long-term behavior, short-term creep-rupture tests at high stress definitely are.
The material difference that causes the spool-to-spool variations has not yet been identified for all eight spools. However, it appears that Kevlar behavior at lower pressures may be predicted through the use of curves fitted to the data for each spool. A power law relating failure time to pressure, t = t0(p/p0)m, was found to fit the data reasonably well. From these fits were constructed design-allowable life values with an expected reliability of 0.999999; these predictions are supported by data on vessels at 17.2 MPa (2.5 ksi), where no failures have occurred after 4½ years. The power law fits also demonstrated the extreme sensitivity of failure time to pressure (m ≈ −15 to −25). This implies that, both in composite vessel design and in creep-rupture experiments, the pressure (or stress) level must be carefully controlled.
Thermal Aging Capsule Results from Oconee Nuclear Station—Unit 1
Authors: Lowe AL 
Published: March 2009

At the Oconee Nuclear Station—Unit 1 a thermal aging capsule was removed and tested at the same time a second reactor vessel surveillance capsule was removed for testing. The thermal aging capsule had received a thermal exposure of 15000 at 580°F (305°C) and the irradiated capsule had received an exposure of 1.5 × 1018 n/cm2. The capsule contained Charpy V-notch and tension specimens of SA-302 B modified base and weld metal and SA-533 B1 correlation monitor material.
The SA-302 B base metal exhibited no significant changes in Charpy V-notch impact properties as a result of thermal aging. The heat-affected-zone data indicated a drop in upper shelf properties. This drop was attributed to limited thermal aged data points and large scatter in the base data, since the notch lateral expansion and shear fracture data did not indicate the same trend. The SA-302 B weld metal exhibited a slight increase in upper shelf energy, and the SA-533 B1 correlation material exhibited a slight decrease in upper shelf energy. No tension data are reported. The conclusions of this study agree with the results reported from the Big Rock Point reactor.
A Comparison of Fire Resistive Coatings in ASTM E 119 and Proposed ASTM E 5 Hydrocarbon Pool-Fire Test Environments
Authors: Gratzol OK , Diliberto MC 
Published: March 2009

The exposure of proprietary fireproofing materials and concrete to the proposed ASTM Standard Hydrocarbon Pool-Fire Test Environments (E 5) does not exhibit any significant difference for thermal shock from ASTM Fire Tests of Building Construction and Materials (E 119-76).
The duration of protection is reduced in the hydrocarbon pool-fire environment, but the areas under the furnace time/temperature curves are essentially unchanged. The shorter duration is offset by the area under the curve attributed to the more rapid heat rise for specimens compared with those tested using ASTM E 119. There appears to be a measurable relationship between the proposed ASTM E 5 hydrocarbon pool-fire and ASTM E 119 tests, which provides data to forecast the result of one to the other for a given furnace and set of circumstances.
This work was undertaken to compare the effects of the proposed ASTM E 5 simulated hydrocarbon pool-fire on fire resistive coatings and poured-in-place concrete versus the standard ASTM E 119-76 time/temperature criteria. Specimens of similar construction were tested in both environments. A hose stream, similar to that used in petrochemical industry fire-fighting practices, was used on the specimens tested in the hydrocarbon type fire to evaluate the erosive effect and thermal shock characteristics of the generic proprietary products in the marketplace. All specimens showed some erosion.
The test program showed no reason to incur the cost of testing to the proposed ASTM E 5 Hydrocarbon Pool-Fire Test Standard, as 3-h ASTM E 119 rated fireproofing, and 50-mm (2-in.) poured-in-place concrete provided similar correlations between both tests.
A Comparison of Critical Properties of Magnesium Oxysulfate and Magnesium Oxychloride Cements as Used in Sprayed Fire Resistive Coatings
Authors: Herrera ME 
Published: March 2009

Magnesium oxysulfate cements although not as strong as magnesium oxychloride cements are better suited for fire resistive uses. Magnesium oxysulfate cements start to decompose at temperatures more than two times higher than magnesium oxychloride cements decompose giving longer fire protection. Their products of decomposition at elevated temperatures are less noxious (sulfur dioxide) than those of oxychloride (hydrochloric acid) and less corrosive.
Weather conditions (humidity, temperature, and wind) during application are not as critical with oxysulfates as with oxychloride, which may partially form unstable magnesium hydroxide instead of magnesium oxychloride. Commonly known as “burnout” or “dry set,” this unwanted reaction can be the cause of loss of bond, cracking, loss of volumetric stability, poor physical properties, and corrosion. Since fire resistive coatings are generally light in density, they are not expected to be as strong as flooring products where the oxychlorides are normally used and are superior. For the intended use as fire resistive and insulative coatings, when those properties are compared, magnesium oxysulfate cements are preferred.
Statistical Scatter in Fracture Toughness and Fatigue Crack Growth Rate Data
Authors: Johnston GO 
Published: March 2009

The use of probabilistic fracture mechanics to assess the reliability of engineering structures requires knowledge about the statistical scatter of the parameters used in the models.
A review is given of the statistically defined tanh reference toughness curves. This method is then used to aid an investigation into the effect of tighter chemical specifications. The predicted curves and small quantity of available published data do support the hypothesis of improved brittle/ductile transition temperatures with controlled chemistry. An experimental program has been undertaken to obtain plain plate data that are then used to derive an empirical correlation between KIc and Charpy energy, assuming the distributions of crack tip opening displacement and Cv can be related for lower shelf temperatures. Tolerance limits and sample size estimates are also obtained for specified confidence levels.
Data on fatigue crack growth rates have been reviewed and the effects of parameters, such as stress ratio, temperature, and irradiation, studied qualitatively. A statistical analysis of published data has enabled a distribution for C in the Paris law to be derived assuming a linear ℓn C versus m relationship.
Finally, an illustrative example calculates the change in failure probability with the number of accumulated cycles.