bluuebunny/crossref_metadata_2025 huggingface dataset:
Three Dimensional, Axi-Symmetric Geomembrane Tension Test
Authors: Koerner RM , Koerner GR , Hwu B-L
Published: March 2009

Presented in this paper are details of a three dimensional, axi-symmetric, tension test used to determine the stress-vs-strain behavior of geomembranes. From this data the modulus, strength and elongation can be obtained. After evaluating the effect of load rate, the accuracy of the test was illustrated by a series of 10 tests on VLDPE geomembranes. This test series resulted in a standard deviation of approximately ± 10%. A variety of different HDPE geomembranes were evaluated with only nominal differences resulting from different manufacturing processes. Lastly, a variety of different geomembrane types were tested and compared to one another. All of these test results show a marked contrast to the usually performed one dimensional tension tests and result in substantially different behavioral trends.

The test details and procedures are presented along with the theory that is required to convert the pressure-vs-deflection readings into stress-vs-strain values. The test is recommended for the type of out-of-plane loading conditions that occur at the bottom of reservoirs and landfills, and for liners used for covers over subsiding landfills and other compressible subgrade materials.
Minimization of the Effect of Dimensional Variability on Geotextile Property Data for Interpretation of Chemical Compatibility Test Results
Authors: Allen SR , Verschoor KL
Published: March 2009

Geotextiles have grown substantially, both in number and in application, during the past ten years. The mechanical properties of a specific region along a geotextile roll length are largely dependent upon mass and dimensional characteristics corresponding to that region. Geosynthetic manufacturers and testing laboratories have adopted various sampling procedures and data manipulation schemes in an effort to minimize the effect of product variability on mechanical property test results. Alternative test methods have been employed that demonstrate a high degree of repeatability. This paper reviews the various approaches to the problem of dimensional variability and discusses their rationale.
Direct Shear Friction Testing for Geosynthetics in Waste Containment
Authors: Bove JA
Published: March 2009

Sliding stability for landfills, heap leach pads and caps constructed using geosynthetics is of critical importance for both short and long term performance of these facilities. For layered facilities, instability along critical slip planes must be considered for construction and operation of the facility.

The direct shear friction test, now being developed under ASTM D35, is the test used to generate important performance data for use in stability determinations.

This paper addresses the main elements of direct shear friction testing and analysis including discussions on the required test apparatus, specimen preparation and soil placement. Differences in testing geosynthetics in contact with other geosynthetics or soils are highlighted. Sources of potential bias in test data are discussed along with recommended solutions. Interpretation of direct shear friction data for use in performance evaluation is included.
Biological Activity and Potential Remediation Involving Geotextile Landfill Leachate Filters
Authors: Koerner GR , Koerner RM
Published: March 2009

This paper presents the results of a biological growth study in geotextile filters used in landfill leachate collection systems. After reviewing the first year's activity, a completely new experimental approach has been taken. Using 100 mm diameter columns for the experimental incubation and flow systems, the effects of six landfill leachates are evaluated. Aerobic and anaerobic states, four different geotextiles, and soil/no soil conditions above the geotextiles are involved in the testing program. This results in 96 individual test columns. Flow data is measured regularly, and over the first six months of evaluation the following trends have been observed. • no clogging (0%–25% flow reduction) 6 of 96 columns = 7% • minor clogging (25%–50% flow reduction) 4 of 96 columns = 4% • moderate clogging (50%–75% flow reduction) 37 of 96 columns = 38% • major clogging (75%–95% flow reduction) 35 of 96 columns = 36% • severe clogging (95%–100% flow reduction) 14 of 96 columns = 15%

For two of the landfill leachates, backflushing has been attempted so as to reinstitute flow. This procedure works well for the geotextile alone while not as well for the geotextile/soil columns. The exception is the nonwoven heat set geotextile. All tests are still ongoing and will be dismantled and further investigated at the end of 12 months exposure time. The experimental setup and procedure has been written up as a tentative ASTM test method and is currently in task group review.
Design and Testing of a Landfill Final Cover With Geomembrane
Authors: Paruvakat N , Sevick GW , Boschuk J , Kollodge S
Published: March 2009

In order to evaluate the feasibility of construction and the adequacy of design of a landfill final cover incorporating a geomembrane, a three-phase investigation was conducted. The frictional characteristics of a sand-geomembrane interface was determined using a tilt apparatus. Stability of an element of the final cover under the design rainfall and freeze-thaw conditions was evaluated using a large size tilt table. Two test plots constructed at 25 percent slopes and periodic observations for over a year provided information on construction feasibility and the behavior of the final cover system under field conditions. Based on the results of the three phases of investigations it was concluded that final covers incorporating geomembranes can be designed and constructed for slopes of 25 percent.
Comparison of Short- and Long-Term Toxicity Test Results for the Green Alga, Selenastrum capricornutum
Authors: Versteeg DJ
Published: March 2009

Algae are important components of many aquatic communities that can be sensitive to effects of aquatic pollutants. Standard algal toxicity tests quantify effects on population growth over 3 to 14 days. These population growth tests are useful for environmental hazard assessment but have limitations. These limitations include test duration, pH, nutrient and metabolite changes during toxicity testing, inability to test at the community level, potential interaction between algal media and test materials, and poor control or understanding of the effects of sample volatilization, sorption, biodegradation, photolysis, or hydrolysis on test material toxicity. These test limitations can be addressed in short-term (<4 h duration) toxicity tests.

Short-term algal toxicity tests were conducted with seven pure compounds and three municipal wastewater treatment plant effluents, and the results were compared to those obtained in a standard four-day population growth test (PGT). The short-term tests involved exposure of the green alga, Selenastrum capricornutum, to test materials and quantification of effects on oxygen generation (O2) in a 30-min exposure and 14CO2 fixation in a 35 min exposure. For test materials used in this research, the short-term tests were consistently less sensitive than the PGT, with ratios of the EC50 (effective concentrations) for the CO2:PGT and the O2:PGT ranging from 1.4 to > 161. However, short-term to long-term test ratios were consistently less than 20, indicating that these tests may be appropriate systems to study effects of test material on algae without the limitations of the long-term test. Although the short-term algal test methods have their own set of limitations for environmental hazard testing, the information gained in the short-term approaches can be used to complement information gained in long-term toxicity tests. This research has demonstrated the relative sensitivities of two short-term tests.
Chemical Effects on the Germination and Early Growth of Terrestrial Plants
Authors: Gorsuch JW , Kringle RO , Robillard KA
Published: March 2009

A rapid, simple, and cost-effective testing procedure is described for determining the potential of a chemical to affect germination and early growth of terrestrial plants. Radish (Raphanus sativus L. var. Champion 708), lettuce (Lactuca sativa L. var. 525 Ithaca M.T.O.), and perennial ryegrass (Lolium perenne L. var. Manhattan) are routinely used in this test because of their economic and ecological importance, quick and high rate of germination, and relatively uniform root and hypocotyl/coleoptile growth. Plants are exposed to the chemical for seven days, after which germination, root length, and plant height values are determined. Average values for treated plants are compared with the corresponding values for the control (untreated) plants. An observed ratio (treated versus control means) of <90% is considered to be a significant indication of adverse chemical effect.

Test results for 26 commercial chemicals are compared with information in the literature. For these commercial chemicals, reduction in root length was the most sensitive plant response, followed by reduction in the plant height. By comparison, germination was not noticeably affected. Ryegrass and radish were found to be equally tolerant species, and lettuce was the most sensitive plant species. Where data for other plant-effect methods are available, comparisons show that this method is generally of equal or greater sensitivity in identifying the potential for chemical effects.
Comparison of the Seagrass Thalassia testudinum and Its Epiphytes in the Field and in Laboratory Test Systems
Authors: Clark JR , Macauley JM
Published: March 2009

Thalassia testudinumand associated epiphytes from field plots were compared with plants from laboratory microcosms to determine if laboratory observations obtained from plants undergoing seasonal growth patterns were characteristic of plants in natural systems. The measurements selected for characterizing Thalassia health were chlorophyll and protein content of leaves and carbohydrate content of rhizomes. For epiphytes, we measured standing crop and chlorophyll content. Mean values for field and laboratory data were statistically analyzed for two experiments conducted over six-week intervals and for one experiment extended to twelve weeks. Thalassia plants in the laboratory followed similar trends of field plants during the six-week experiments, but the laboratory plants differed significantly from field plants at twelve weeks. Chlorophyll content of epiphyte communities colonizing Thalassia leaves was significantly different in the laboratory compared to field communities, but trends from test initiation to the six-week sampling were consistent between field measurements and laboratory test systems.
Use of Native and Cultivated Plants as Bioindicators and Biomonitors of Pollution Damage
Authors: Weinstein LH , Laurence JA , Mandl RH , Wälti K
Published: March 2009

Plants are among the most sensitive organisms to pollutants, often responding with distinct, easy-to-recognize symptoms from exposure to specific environmental contaminants. This characteristic makes plants useful as bioindicators and biomonitors of pollutants. Using plants as bioindicators offers several advantages over physical/chemical monitoring systems: plants are easy to grow and maintain and inexpensive to deploy at a great number of sites; plants integrate pollutant exposure with other environmental factors to provide a biological assessment of exposure; and plant samples may be archived for retrospective analysis. Systems in use include indicator gardens, lichen transplants, plant growth and exposure benches, standard grass cultures, field survey of indigenous or cultivated species, and chemical analysis of plant tissue. A case study illustrating the use of bioindicators to assess the level of fluoride pollution in the Rhône valley in Switzerland is presented.
Time-Dependent Toxicity Assessment of Herbicide Contaminated Soil Using the Green Alga Selenastrum capricornutum
Authors: Thomas MW , Judy BM , Lower WR , Krause GF , Sutton WW
Published: March 2009

Bioassays utilizing the green alga Selenastrum capricornutum were performed on filtered eluates from soil treated with six commonly used forestry herbicides applied at labelrecommended rates. The bioassays were conducted at three time periods after herbicide application—one hour, five days, and ten days. The 96-h EC50 values indicated growth inhibition (relative to control sample) for all treatments when assayed 1 h after herbicide application. Algal EC50 values of +100 (Control), +27.3 (Roundup™), -20.4 (Arsenal™ [2 lb Acid Equivalent] [AE]/gal), -22.4 (Garlon™ 4), -49.4 (Tordon 101M™), -100 (Velpar L™), and -100 (Velpar ULW™) were obtained. Assays conducted ten days after herbicide application to soil revealed substantially reduced toxicity of two herbicides. The 96-h EC50 values for Roundup and Arsenal were both +100. There was a significant enhancement effect observed with Roundup. A slight reduction in toxicity was noted for Garlon 4 (-15.9) and Tordon 101M (+9.9). No change in toxicity occurred for Velpar L or Velpar ULW. The herbicides were also applied to water and the following 96-h EC50 values in μg/ml were obtained: 5500 (Arsenal [2 lb AE]), 5300 (Arsenal [4 lb AE]), 5000 (Tordon 101M), 5000 (Garlon 4), 2600 (Roundup), 2.5 (Velpar L), and 1.2 (Velpar ULW).
Chlorophyll Fluorescence of a Higher Plant as an Assay for Toxicity Assessment of Soil and Water
Authors: Judy BM , Lower WR , Miles CD , Thomas MW , Krause GF
Published: March 2009

The chlorophyll fluorescence (CF) assay is recognized as an important tool for monitoring the electron transport system of photosynthesis. The increase or decrease of fluorescence, compared to control, can indicate a lesion in the chain of events in photosynthesis or damage to the chloroplasts. Inhibition of photosynthesis in leaf segments of Tradescantia by herbicides (glyphosate, picloram & 2,4-D, triclopyr and hexazinone), heavy metals (Zn, Cu, Cd), a surfactant (sodium lauryl sulfate), and sodium fluoride (NaF) has been demonstrated using this method. The strongest changes of fluorescence induction curves were caused by hexazinone. Photosynthetic inhibition was observed as an increase in initial fluorescence (Fo) and a decrease in variable fluorescence (Fv) and electron pool size (EP). A CF assay predicted herbicidal injury in Tradescantia leaves at least 24 h before leaf necrosis appeared.

Three heavy metals (Zn, Cu, Cd) are known as strong respiration and photosynthetic inhibitors in plant cells. In this study cadmium chloride, at the highest concentration (1000 ppm) tested, caused the strongest changes in Fv and EP size, which are characteristics of Photosystem II (PS II) photochemistry. Phytotoxicity of NaF caused an increase in Fv and EP compared to the control.
Image Analysis System for Rapid Data Processing in Tradescantia-Micronucleus Bioassay
Authors: Xu J , Xia W , Jong X , Sun W , Lin G , Ma T-H
Published: March 2009

Tradescantia-micronucleus (Trad-MCN) bioassay is a well established short-term test for environmental mutagens in liquid or gaseous forms. For large-scale experiments that involve hundreds of slides, the micronuclei scoring process, data collection, and analysis are labor intensive and time consuming. Using computer image analysis process, a rapid data processing system was developed. This new facility is called the Trad-MCN Image Analysis System (Trad-MCN-IAS). The hardware of this system is composed of a photomicroscope attached to a video camera and a US-386 computer. The software for this system was written in FORTRAN language and run under an FG-105 real-time image processor. The operation begins with multi-threshold image segmentation, followed by mathematical morphology-based micronucleus extraction, and judging of normal tetrads with pseudo-color display. Using this system, a large number of tetrads (the four-cell stage of the meiotic pollen mother cells) image on the screen can be scored simultaneously for normal and micronucleus-bearing tetrads. The number of micronuclei in a large population of tetrads can be recorded and put in memory for data analysis. For high efficiency, four microscopes may be installed on a single Trad-MCN-IAS to gather tetrad images and count micronuclei; therefore a large number of samples can be scored and the experimental data processed in a short time. This system has several advantages: non-bias in the scoring process, automation, and minimizing the variance of scores introduced by different human observers.
Stress Wave Sensing - Affordable AE for Industry
Authors: Holroyd TJ , Tracey TE , Randall N , King SD
Published: March 2009

A fully integrated stress wave sensor has been created which incorporates the basic functions of an AE system. The sensor is mounted in a robust and easy to install housing which greatly simplifies the sensing of stress wave activities in the industrial environment. The use of signal enveloping techniques in the sensor eases the subsequent handling of its outputs whilst retaining the useful information in the detected stress wave signal. A number of applications are discussed to illustrate the versatility of the approach described.
Joule Heating Line and Point AE Sources and the Adhesion of Thin Metal Films
Authors: Kim KY , Sachse W
Published: March 2009

This paper describes a novel approach for generating line and point sources of ultrasound from a thin metal film attached to an insulating substrate. Both line and point sources are generated by a transient, electrical Joule heating of a long- and a short section of the thin film of narrow width, respectively. It is shown that the line and point sources are of dipolar type. By deconvolving the detected ultrasonic signals it is found that a current pulse of short duration generates a step source with risetime approximately equal to that of an input power pulse while a current pulse of long duration produces a linear ramp source resembling the temporal behavior of the temperature rise in the heated thin film. It is also shown that the failure of the film can be detected in the generated ultrasonic signals as well as in the measured electrical resistance of the film. By suitably processing these signals, information on the adhesion strength of the film to its substrate can be found.
Simultaneous Velocity Tomography and Source Location of Synthetic Acoustic Emission Data
Authors: Maxwell SC , Young RP , Hutchins DA
Published: March 2009

A method is proposed to simultaneously determine source locations, and passively image the velocity structure of a deformed sample. The method utilizes arrival time data measured from recordings of induced acoustic emissions. Images of the velocity structure are sensitive to the state of stress in a sample, and can be used to map spatial variations in stress induced changes. This study documents the first phase of a passive imaging research project. Synthetic arrival time data were used to attempt to passively image a velocity model, using both spatially uniform and restricted event coverage. In both cases, the actual model was reproduced, however the restricted event coverage resulted in some loss of resolution. Sequential passive imaging should prove to be a powerful tool for imaging the evolving in-situ stress field using only basic monitoring instrumentation.
Acoustic Emission Technology Using Multi-Parameter Analysis of Waveform and Application to GFRP Tensile Tests
Authors: Yamaguchi K , Oyaizu H , Johkaji J , Kobayashi Y
Published: March 2009

Advanced acoustic emission instrumentation systems which can use multi-parameter data obtained by wave-envelope processing of all detected AE's have been developed. The systems were applied to different experiments such as fracture-monitoring of metal-structures and testing of materials. New parameters such as energy moments and zero crossing number were used together with conventional parameters and showed the usefulness for waveform analysis and source classification. In tensile tests of GFRP, the results indicated the high identification possibility, on failure modes such as fiber-debundling, matrix-cracking and fiber-breakage. The performance of the advanced systems can be considered more powerful for material evaluation than that of usual systems depending on conventional AE parameters such as peak amplitude and event count, etc.
Solving AE Problems by a Neural Network
Authors: Grabec I , Sachse W , Govekar E
Published: March 2009

This paper summarizes recent work utilizing an adaptive learning system to the characterization of acoustic emission phenomena. The processing system resembles a neural network including an associative memory. Data is input into the system as a vector composed of either AE signals or their spectra and encoded information about the source. The mapping of AE signals from the sensors to the descriptors of the source and vice versa is accomplished by learning in the system. This is performed by presenting experimental signals to the system and adaptively forming a memory whose output is an autoregression projection of the input. Discrepancies between the input and output are applied in a delta learning rule. Experiments are described which utilize a system running on a minicomputer to process signals from a localized, simulated source of discrete acoustic emission events in a block of material and to process the AE signals generated during a metal drilling operation. It is shown that the characteristics of the source can be estimated from the AE signals or vice versa by the auto-associative recall from the correlation memory.
Periodic Inspection of Compressed Gas Cylinders and Transport Vessels by Using Acoustic Emission Testing
Authors: Barthélémy HM
Published: March 2009

Gas cylinders and large transport vessels used for industrial compressed gases are subjected to hydrostatic retests. In this paper are presented results of an investigation concerning how to apply acoustic emission tests during such periodic inspections to detect flaws, i.e. internal corrosion and cracks. In conclusion a method for the periodic inspection (hydrostatic test with an acoustic emission testing) of such vessels is proposed. This method allows safe extension of the interval between re-tests.
Effect of Pre-Exposure to Water on the Acoustic Emission Behavior of 2091-T3 Al-Li Alloy
Authors: Zeides F , Roman I
Published: March 2009

The effect of pre-exposure to water with imposed weak ultrasonic field on the acoustic emission (AE) behavior of 2091-T3 Al-Li alloy was studied. AE characteristics were evaluated during tensile deformation utilizing a micro-computer based system and an rms voltmeter. Two types of AE were observed, initially, AE was of a continuous nature with a maximum at the yield, followed by a change to burst type AE coinciding with the onset of PLC serrations. A significant difference in AE behavior between as-received and pre-exposed material has been observed, especially in the yield region. The preexposed specimens gave rise to more intense AE activity manifested in higher peak amplitude AE events. Although the precise mechanism of the observed effect is not known, it is believed to stem from hydrogen charging that took place during pre-exposure, and which also caused reduction of the tensile elongation of the material.
A Comparison of the Acoustic Emission Generated from the Fracture and Decohesion of Graphite Nodules with Theoretical Predictions
Authors: Carpenter SH , Zhu Z
Published: March 2009

It has been known for many years that the fracture and/or debonding of Inclusions or second phase particles during deformation can act as a source of acoustic emission. A number of experimental studies of this phenomena have been reported. Excellent theoretical investigations of the fracture of an elastic spherical particle in a plastic matrix have been carried out and expressions have been derived for the energy released during fracture. However, there is little work where a direct comparison between experimental data and theoretical predictions can be carried out. The purpose of this paper is to report on the acoustic emission generated from the fracture and/or decohesion of spherical graphite nodules during the compressive deformation of nodular cast iron. The correlations of the experimental acoustic emission data with theoretical predictions will be reported.
Evaluation of Fatigue Crack Growth Rate of Carburized Gear by Acoustic Emission Technique
Authors: Obata Y , Kobayashi H , Aoki K , Yamaguchi T , Shibata K
Published: March 2009

Acoustic emission measurements of carburized steel were carried out in room-temperature fatigue tests at the constant load-amplitude condition, in order to evaluate the crack growth behavior. An extremely large number of acoustic emission events were recorded near the maximum load in a flexural fatigue cycle. The increasing behavior of acoustic emission event counts was associated with the distribution of fractured intergranular facets in the fracture surface. Many emissions were also recorded in the spur gear tests. The crack growth rate of the gears can be estimated using the relation between the acoustic emission event counts and the intergranular fracture area on the crack surface. It can be concluded that the acoustic emission technique was powerful and quantitative method to evaluate the fatigue crack behavior of carburized mechanical parts.
Applications of Acoustic Emission Techniques for Diagnosis of Large Rotating Machinery and Mass Production Products
Authors: Sato I , Yoneyama T , Sato K , Tanaka T , Yanagibashi M , Takikawa K
Published: March 2009

In order to maintain efficient plant operability, better reliability and preventive maintenance are required. When a machine experiences some problem during use, operators must find the cause of trouble, then take measures to prevent serious damage. Acoustic emission (AE) is a useful means of machine condition diagnosis. The AE technique can detect incipient failure and locate the source.

This paper describes applications of AE techniques for large rotating machinery diagnosis, development of diagnosis systems using algorithms obtained from AE characteristics analyses, and applications for the diagnosis of rotary compressors in air conditioners.
Cavitation Monitoring of Hydroturbines with RMS Acoustic Emission Measurement
Authors: Derakhshan O , Houghton JR , Jones RK , March PA
Published: March 2009

Acoustic Emission measurements are shown to be a reliable indicator of cavitation pressure pulses. The method of display is the root mean square, RMS, of the AE signal integrated over 1 second that is proportional to the average cavitation energy. An inexpensive AE transducer, amplifier, filter, and RMS circuit is described with a gain of 22 dB and a frequency range of 10 kHz to 1.25 MHz. Data from two laboratory controlled cavitation experiments is presented. The system is tested on two TVA hydroturbines. Kaplan-type and Francis-type turbines had a similar shaped increased RMS AE curve with wicket gate opening but the numerical maximum values are different in each hydroturbine installation. A real-time continuous RMS AE monitor is recommended on each hydroturbine for the evaluation and control of cavitation erosion.
Monitoring of the Machining Process by Means of Acoustic Emission Sensors
Authors: Dornfeld DA
Published: March 2009

Research over the last several years has established the effectiveness of acoustic emission (AE) based sensing methodologies for machine condition analysis and process monitoring. Acoustic emission has been proposed and evaluated for a variety of sensing tasks as well as for use as a technique for quantitative studies of manufacturing processes. This paper discusses some of the motivations and requirements for sensing in automated or untended machining processes as well as reviews the research on acoustic emission (AE) sensing of tool condition (wear and fracture) in machining. The background for AE generation in metal cutting and its relationship to the condition of the cutting tool for single and multiple point tools (turning and milling) is presented. Research results will be summarized relating to the sensitivity of AE signals to process changes, AE signal sensitivity to tool condition in turning and milling for wear and fracture, AE signal processing methodologies for feature extraction including time series modeling to remove influences of machining conditions on wear tracking and AE sensor fusion using neural networks for process monitoring with several sensors.
Microseismics and Geotechnical Applications
Authors: Ohtsu M
Published: March 2009

AE events in the low frequency range (⟨1 kHz) are sometimes referred to as microseismic activity. In microseismics and geotechnical applications, higher frequency components are preferentially attenuated. The detection of low frequency components can minimize the effect of material inhomogeneity. So far, quantitative treatment of AE in geotechnical fields is limited to the, source location analysis. In the present paper, a source inversion procedure in geologic materials is discussed. The procedure consists of the SiGMA (simplified Green's function for a moment tensor analysis) inversion to determine moment tensor components and the unified decomposition of the eigenvalues to characterize crack types and crack orientations. AE sources are classified into tensile cracks and shear cracks, and crack orientations are determined from the directions of the eigenvectors. As an application, AE events observed in a hydrofracturing test are analyzed. Results show a great promise of AE for clarifying failure mechanisms in geotechnical fields.
Acoustic Emission/Microseismic Activity at Very Low Strain Levels
Authors: Armstrong BH , Valdes CM
Published: March 2009

Laboratory experiments have shown that strain levels as low as one microstrain in competent rock samples produce detectable acoustic emissions (AE) in the frequency range from 100 to 300 kHz. Naturally occurring strain and strain rates have similar levels to those at which laboratory AE was detected. In the buildup of a strain field over the “preparation zone” of an impending earthquake, strain in collapsing pores, grain boundary slippage, and other microscopic ruptures may cause high frequency AE. However, this AE due to tectonic strain must be distinguished from AE from other sources such as air pressure changes, thermal expansion/contraction, earth tides, and cultural activities. Sufficient AE at very low strain levels, and detectable above noise backgrounds, might provide a useful precursor to earthquakes.
Acoustic Emission Monitoring of Contact Drying of Southern Pine Veneer
Authors: Beall FC
Published: March 2009

Veneer was contact dried at two pressures and two temperatures to evaluate the formation of defects and drying characteristics as monitored by acoustic emission. The formation of excessive splits was characterized by a stepwise pattern of acoustic emission events. The effects of heat transfer and temperature on drying rate could be inferred from the rate of events or shape of the normalized total event curves.
Geoelectrics in Comprehensive Ground Water Contamination Studies
Authors: Mazac O , Kelly WE , Landa I
Published: March 2009

A suite of geoelectric techniques were used to characterize an aquifer for a pollution study. Vertical electrical soundings were used to define aquifer layer resistivities and thicknesses. Porosities, hydraulic conductivities, and transmissivities were then estimated from the resistivities and thicknesses. The mise-a-la-masse method was used to define direction of flow, tracer velocity, and dispersion coefficients. Finally, borehole logging was used to obtain additional information on porosities and velocities.
Use of Piezometric Cone Penetration Testing with Electrical Conductivity Measurements (CPTU-EC) for the Detection of Hydrocarbon Contamination in Saturated Granular Soils
Authors: Strutynsky AI , Sandiford RE , Cavaliere D
Published: March 2009

Piezometric Cone Penetration Testing with soil Electrical Conductivity measurements (CPTU-EC) was used for the detection of hydrocarbon saturated granular soils at two airport fuel storage areas. Details of the CPTU-EC equipment and site subsurface conditions are provided. Test program phases, including laboratory testing, field insitu testing and CPTU-EC data interpretation are described. Comparisons are made between CPTU-EC and adjacent monitor well data. Limitations to the CPTU-EC method are discussed.
Use of Piezometric Cone Penetration Testing and Penetrometer Ground Water Sampling for Volatile Organic Contaminant Plume Detection
Authors: Strutynsky AI , Sainey TJ
Published: March 2009

Piezometric Cone Penetration Testing (CPTU) and penetrometer ground water sampling were used to locate a volatile organic contaminant plume at an industrial site in southern Ohio. Nine CPTU tests (soundings) were performed to determine site hydrostratigraphy in real-time. On-site chemical analysis of penetrometer ground water samples provided near real-time detection of contaminants. These results were used to define subsequent monitor well locations. Using this investigation approach, drilling operations to set monitor wells began as penetrometer exploration ended. Program quality increased, while exploration costs decreased by using this combination penetrometer-drilling rig approach.
Design and Construction of Deep Groundwater Monitoring Wells
Authors: Beard LD
Published: March 2009

Deep groundwater monitoring wells for the Colbert Landfill Superfund Project in Spokane County, Washington were constructed using 6.4-cm (2.5-in.) diameter Polyvinylchloride (PVC) well casing, instead of 5.1-cm (2.0-in.) diameter casing, to provide additional strength and a larger inner well diameter for groundwater sampling equipment. Two well screen/filter pack combinations were used to provide the convenience of preconstruction purchase of well construction materials, and the flexibility to adjust the well intake design for site-specific hydrogeologic conditions. High percent-solids bentonite grout was used for the annular seal in lieu of a bentonite pellet seal to avoid material bridging during installation. Well casing alignment was maintained by applying a tensile force to the casing during the placement of annular fill materials rather than using casing centralizers. Also, threaded temporary steel casing was used for borehole support (versus welded temporary steel casing) to reduce boring and installation time and expense. This monitoring well design and construction approach maintained construction quality standards and resulted in significant cost savings by eliminating common deep well construction problems.
Considerations in Selecting Indicator Parameters for the Statistical Evaluation of Ground-Water Quality
Authors: Pastor EF , Frick DR
Published: March 2009

An essential component of a detection ground-water monitoring plan is the establishment of a program for the statistical evaluation of ground-water chemistry data. The objective of such a data evaluation program is to assess whether there is statistically significant evidence of ground-water contamination, based on the indicator parameters for the site being monitored. The occurrence of false conclusions of evidence of contamination (Type I errors) or failures to detect contamination when it actually is present (Type II errors) is minimized by the use of appropriate indicator parameters.

To optimize the effectiveness of a statistical evaluation program, a limited number of indicator parameters should be selected on a site-specific basis, consistent with the following factors: (1) Concentrations of the parameter in contaminant source and background ground-water samples; (2) Hydrogeologic conditions of the site being monitored, particularly as they may affect spatial and temporal variability of parameter concentrations in ground water; (3) Chemical fate and mobility characteristics of the constituents used asindicator parameters; (4) Precision and limitations of the laboratory analytical procedure specified for the parameter; and (5) Characteristics of the existing dataset (if any) for the parameter. This paper explain the importance of the above factors and provides examples from a number of case studies to illustrate their use.
Development of a Method to Evaluate the Puncture Resistance of Protective Clothing Materials
Authors: Lara J , Nelisse NF , CÔté S , Nelisse HJ
Published: March 2009

Various parameters relevant to the puncture resistance of protective clothing materials were studied. The experimental set-up was installed in an Instron testing machine. Testing was performed in a compression mode. A point was installed in a 890-newton (200-lb) load compression force cell in the movable arm of the machine, and a sample support was installed in the fixed arm in the base. The first parameter analyzed was point geometry. Three geometries were evaluated: conical, hemispheric and flat points. The effect of the diameter of the points on the results of the puncture test was also evaluated. A neoprene material with three different thicknesses (0.41 mm, 0.7 9 mm and 1.57 mm) was used as reference material. The tests were performed at various speeds of the movable arm from 10 to 500 mm/min. Results showed that the point having a hemispheric geometry gives the best reproducibility. Hemispheric geometry points were therefore used to test the puncture resistance of commercially available gloves. A classification of the gloves into four groups is proposed.
A Comparison of Methods for Measuring the Liquid Barrier Properties of Surgical Gowns
Authors: McCullough EA , Schoenberger LK
Published: March 2009

The liquid barrier properties of woven reusable and nonwoven disposable surgical gowns were measured using seven test methods (AATCC 42 Water Resistance: Impact Penetration Test; AATCC 127 Water Resistance: Hydrostatic Pressure Test; IST 80.7 Mason Jar Test; Kimberly-Clark Blood Strike Through Test; ASTM F 23.40.01 Draft Standard Test Method for the Resistance of Protective Clothing Materials to Biological Fluids conducted at 1 and 2 psi; and Gore Elbow Lean Test) and four challenge liquids (distilled water, bovine blood, synthetic blood, and 70% isopropyl alcohol). The impervious gowns which were reinforced in the front and sleeve areas with liquid proof coatings or films passed all tests when the data were averaged across all liquids. The cotton/polyester traditional gown failed every test. The regular nonwoven gowns constructed of a single layer of fabric passed some tests with some liquids, but failed most of the time. The fabric reinforced gown performed better than the regular gowns on some tests. Isopropyl alcohol was the most challenging liquid, in that more fabrics failed the tests with this liquid than the others. The bovine blood was the least challenging. Synthetic blood is recommended for barrier testing.
A Comparison of the Liquid Penetration Test with Other Chemical Resistance Tests and its Application in Determining the Performance of Protective Clothing
Authors: Stull JO , White DF , Greimel TC
Published: March 2009

ASTM F903, the standard method for measuring the resistance of protective clothing materials to penetration by liquid chemicals, was first introduced in 1987. Since this time, extensive experience has been gained with its use and the application of penetration resistance data. The method involves placing a material in a test cell which allows one-sided contact of the specimen with a liquid chemical. In its newest revision, the length of exposure and pressure applied behind the chemical may be chosen by the laboratory and can impact test results. Penetration is detected visually but may be enhanced by a number of techniques. Interpreting penetration results requires an understanding of ways different material specimens may fail. Test specimens other than flat materials may be accommodated within the test cell using special gaskets or sealing methods. Penetration resistance data is not widely used by the chemical protective clothing industry. Most clothing manufacturers choose to report permeation resistance data for their products. However, the choice of permeation versus penetration testing is dependent on the type of protection desired and the relative hazards of the environment. Penetration testing offers a viable means of demonstrating protective clothing material barrier performance against liquids and as such is suited as the appropriate chemical resistance test for liquid splash-protective clothing.
Thermo-Man® and Thermo-Leg: Large Scale Test Methods for Evaluating Thermal Protective Performance
Authors: Behnke WP , Geshury AJ , Barker RL
Published: March 2009

Laboratory test methods are described which use instrumented manikins to obtain realistic assessment of the thermal protective performance of heat resistant garments in exposure to intense heat such as generated in flash fire accidents. One system, called the Thermo-Man® evaluation system, provides evaluation of thermal protection of a full clothing system in a stationary configuration. The other system, the Thermo-Leg evaluation system, provides assessment of the ability of clothing materials to protect the wearer under realistic simulation of running motion similar to a victim escaping a flash fire accident. Both systems use sophisticated heat sensing instrumentation to provide substantial information on the ability of garment materials to protect against 2nd and 3rd degree burn injury. They also provide a visual means of evaluating the distribution of the burn injury on the human body. The utility of these full-scale test methods is demonstrated in experiments that compare the thermal protective performance of selected garments made of Kevlar® and Nomex® aramid fibers, and of FR wool and FR cotton fabrics.
Field Test Evaluation of ASTM Standard F-1154 with Chemical Protective Suit Ensembles
Authors: Veghte JH , Storment S
Published: March 2009

Experienced fire fighters with Hazardous Materials training participated in field tests using procedures described in ASTM F-1154 to evaluate the fit and function of fully encapsulated and disposal type chemical protective ensembles. These evaluations were performed outside under various climatic conditions at the Sacramento, CA; Phoenix, AZ; Prince George's County, VA; and, Del Ray Beach, FL Fire Departments. Initial trials at the first test site in Sacramento showed that tasks described in either Procedure A and B of the ASTM standard were not rigorous enough by themselves to evaluate these ensembles. So all the tasks (16) were combined and used to assess the physiologic responses of the fire fighters. Based on these findings, a different suit integrity test was formulated and the disposable type chemical protective clothing was evaluated under field test conditions. This evaluation quickly identified several weak areas in the suits' construction and is reported in this study.
A Preliminary Study of an Intermittent Collection Procedure as an Alternative Permeation Method for Non-Volatile, Water Soluble Chemicals
Authors: Pinette MFS , Stull JO , Dodgen CR , Morley MG
Published: March 2009

This paper proposes a novel collection procedure which takes into account the properties of oil mixtures, heavy pesticides, and other low volatile, low water soluble compounds. The procedure involves an intermittent splash collection of the permeant using an appropriate solvent and several options for subsequent detection. This paper compares our procedure with test procedures currently proposed in the revision of the F739 standard method, using a solid absorbent collection method, to determine its efficiency. Based on this information, data show permeation results for each method and discuss the advantages and disadvantages with both collection approaches. We propose that the intermittent splash based collection method become the standard test procedure for permeation testing of chemicals which are not sufficiently volatile for collection by gases and which cannot be samples using aqueous collection methods.
A Comparative Study of Permeation Tests: Gravimetric Method vs ASTM Method F-739
Authors: Lara J , de Merchant J , Ketelson H
Published: March 2009

A comparative study of the F-739 ASTM permeation test method and the gravimetric test method using different types of gravimetric permeation cells was performed. Two aluminum gravimetric cup cells and one commercial glass jar was used. Independent of the type of gravimetric permeation cell used, breakthrough time and permeation rate values obtained using the gravimetric method are equivalent to those obtained using the ASTM method. Problems with safe handling and with the cell seals were found with the first type of cup cell tried. A new type of conical cell that is easier to handle was developed.
An Evaluation of a Permeation Field Test Kit to Aid Selection of Chemical Protective Clothing
Authors: Stull JO , Veghte JH , Storment SB
Published: March 2009

The U.S. Environmental Protection Agency has developed a field kit based on a permeation cup test, to aid in the selection of chemical protective clothing. The operation of the permeation field test kit is based on a gravimetric method. This involves placing a small amount of test chemical in the permeation cup, and weighing the assembled cup. The cup is then removed from the balance and placed on a stand in an inverted position, so that the chemical is in direct contact with the material. The stand allows air to flow across the surface of the material to remove permeating vapor. Periodic weighings are conducted for approximately one hour or other established test period. Cup assembly weight loss data can then be used to determine the permeation resistance of the tested material. Prototype kits were evaluated by the U.S. Fire Administration for their application in hazardous chemical emergency response. Evaluations were conducted at four fire department locations; Sacramento, California; Prince George's County, Maryland; Phoenix, Arizona; and Del Ray Beach, Florida. Each location presented a different set of climatic conditions in terms of humidity and temperature. The test matrix consisted of five chemicals and five materials. Chemicals were chosen to represent a range of volatility while clothing materials were sampled from different types of garments. Triplicate tests were conducted for each material-chemical combination. Improvements were successively made in the kit's design and procedures and also evaluated during the study. The results were analyzed for intrasite and intersite variation as well as being compared to laboratory test data. The study demonstrated the utility of the kit in emergency response applications. Observations from this and related studies have indicated a number of changes to additional applications, changes to kit design, and methods for interpreting the data.
Application of Three ASTM Test Methods to Measure Thermal Resistance of Clothing
Authors: Bomberg M
Published: March 2009

This paper describes the application of three ASTM methods developed for testing thermal insulating materials to measure thermal resistance of clothing fabrics. To permit testing fabrics with small thermal resistance, a standard air layer was incorporated as a part of the test assembly. This air layer, placed on the cold side of tested fabric, is used for two reasons: (1) to reduce experimental errors, and (2) to permit testing radiative properties of the fabric surface.