bluuebunny/crossref_metadata_2025 huggingface dataset:
Measurement and Control Method for Cutting Resistance of Protective Gloves
Authors: Payot F
Published: March 2009

Among industrial injuries, those related to hands are most frequent. The mechanical aggressions essentially depend on the type of activity and most of them are easy to simulate. However, the objective and simple measurement of the cutting resistance of any protective material comes up against the reproducibility of the process, considering the delicate specifications and measurements of the sharpness of the blades used for this purpose. Moreover, we also have to distinguish between cutting by slicing (motion parallel to the surface) and cutting by impact (motion perpendicular to the surface). Whatever the case, the sharpness of the blade needs some sophisticated means of observation, which is expensive. In 1987, I T F - LYON (Institut Textile de France), at the request of I N R S (Institut National de Recherche et de Sécurité), developed a method to measure the cutting effects by slicing where blade sharpness supervision is not necessary with certain limits.

This method consists of measuring the cutting effects on a given material against those measured on a defined control specimen.
An Interlaboratory Comparison of Standard Test Methods for Medical Gloves
Authors: Douglas AA , Neufeld PD , Wong RKW
Published: March 2009

Interlaboratory (round-robin) testing was done on medical gloves of four materials of manufacture. Leak testing was done by air inflation, water fill and chemical fill methods. The reproducibility of each method varies, depending on glove type. The methods also vary in sensitivity; the chemical fill method detects the highest proportion of pinholes. Tensile strength was evaluated by whole finger, ring and dumbbell methods, with the latter found most reproducible.
Assessment of the Resistance of Protective Gloves to Chemicals
Authors: Mahieu J-C , Barat F
Published: March 2009

A study of the resistance of gloves to industrial solvents has been carried out by the French National Research and Safety Institute (INRS — Institut National de Recherche et de Sécurité). The aim of this study was to help French users to select their protective equipment among the gloves which are available on the French market.

Resistance to 8 chemicals was assessed for about 70 protective gloves.Three types of tests were used: Direct permeability test, Kinetic permeability test, and Dynamic dip test.[1]

The results of these three tests are combined and each glove is classified into one of the following three categories:“Not recommended”, “Acceptable”, “Excellent”.

For the time being, the major methods used for assessing protectiveglove resistance to chemicals are based on permeation testing, the results of which provide relevant information but do not adequately take degradation into account. For a more complete evaluation of glove resistance,testing on the whole glove seems to be advisable. For these reasons, it seems important to develop additional testing methods.
Methyl Parathion Residues in Protective Apparel Fabric: Effect of Residual Soils on Decontamination
Authors: Laughlin JM
Published: March 2009

This study evaluated the contribution of oily and particulate soil residue to pesticide residue removal. 100% cotton and 65% polyester/35% cotton, were artificially soiled with a standard soil. The fabrics were laundered with the same substrate fabric without soil. Initial methyl parathion contamination was not dependent on the soil level or fiber content of the fabric. Residues remaining after laundering were affected by soiling level. Pesticide residues were greater when the fabric had a heavy soil build-up even though the initial contamination had been lower. Based on these findings, protective apparel should be kept as clean as possible, with daily laundering, for the presence of soil residue affected decontamination of the fabrics.
Analysis of 2,4-D Glove Permeation under Controlled Environmental Conditions
Authors: Moody RP
Published: March 2009

Field workers in Canada are occupationally exposed to pesticides under diverse environmental conditions of temperature, solar radiation (e.g. ultra violet (UV)), air humidity, etc. that may affect the barrier integrity of chemical protective clothing (CPC). The present study reports a new flow-cell design for testing pesticide permeation in CPC under precisely controlled environmental conditions. Pesticide analysis was conducted by liquid scintillation counting of 14C-ring-labelled 2,4-dichlorophenoxyacetic acid (2,4-D). Studies conducted to determine the permeation of 2,4-D under light (UV) and dark conditions in black neoprene, natural rubber (NR), nitrile butyl rubber, polyvinyl chloride (PVC), and VitonR gloves demonstrated low permeation overall with a maximum of 3.7 ± 1.48% permeation by 48 h in PVC gloves. Significantly greater (P < 0.05) permeation of 2,4-D was observed in NR gloves exposed to UV for 24 h. Advantages of our in-house developed Automated In-Vitro Diffusion Analysis (AIDA) procedure to the standard American Society for Testing and Materials (ASTM) F739-85 method will be discussed.
Method for Assessing the Insulation Properties of Gloves Against Contact Heat
Authors: Paureau J , Rollin M
Published: March 2009

Correlations of pain threshold time ranging from 10 to 590 s versus constant heat flow were determined on the thenar eminence (the bulge at the base of the thumb) of three subjects. These data show that hands behave thermically as a semi-infinite solid in the range 25 to 590 s. The method consists of assessing the pain threshold time from the temperature rise which a semi-infinite solid would experience versus time. In the first version of the method the skin temperature rise is calculated from the recording of heat flow through the sample versus time. In the second version, the surface temperature rise of a block of nylon is measured. The skin temperature rise is 1.48 times less than the temperature rise of the block. Pain threshold was assumed to be reached at a skin temperature rise equal to 12°C. Both versions allow pain threshold time to be assessed directly in the range of 25 to 590 s. For a time less than 25 s, corrections using the correlation of STOLL and GREENE are necessary.
The Effect of Seams and Closures on Pesticide Penetration Through Fabric
Authors: Dimit CA , Easter EP , DeJonge JO
Published: March 2009

Seam and/or zipper closures were evaluated as barriers to pesticides by using a multilayer sample. The sample was exposed to a spray solution of either dicofol or etridiazole using a laboratory spray chamber. The samples were solvent extracted and the extracts were analyzed by High Performance Liquid Chromatograph (HPLC). This study found that the plain seam, and the lapped traditional zipper provided the best barrier to specific pesticides.
Heat Strain Produced by 3 Aircrew Chemical Defence Ensembles Under Hot Conditions: Improvement with an Air-Cooling Vest
Authors: Vallerand AL , Schmegner IF , Michas RD
Published: March 2009

The heat strain produced by three different Canadian Forces chemical defence (CD) individual protection ensembles (IPE) was studied under simulated hot cockpit conditions with an air-cooling vest (AC) and with no cooling (NC). Seven healthy males were randomly subjected to six heat stress tests (37°C, 50% r.h., target of 150 min) using the helicopter IPE with AC-4 mask (H4), the helicopter IPE with AR-5 hood/respirator (H5), and the CF-18 fighter IPE (F) with AR-5 respirator and anti-G suit. Whatever the IPE, AC increased heat exposure time and total heat losses, and decreased the change in core (δTre/h) and whole body mean skin temperatures (δ¯Tsk(WB)/h) (P<0.05). Differences within IPEs appeared restricted to the F-NC condition. F-NC produced a lower heat exposure time (vs H4-NC and H5-NC) and sweat evaporation rate (vs H4-NC), and a greater δ¯Tsk(WB)/h (vs H4-NC and H5-NC) and Tre at min 80 (vs H5-NC) (P<0.05). The results demonstrate that air cooling greatly enhances heat tolerance of subjects wearing any of the 3 CD IPEs tested. They also indicate that without cooling, both helicopter IPEs produce slightly better tolerance to heat than the fighter IPE, possibly an influence of the anti-G suit on evaporative cooling.
Thermal Constraints Related to the Wearing of Protective Clothing. Body Ventilation by Fresh Air
Authors: Bittel J , Hanniquet A-M , Frossard H
Published: March 2009

In order to protect people in a contaminated environment, protective clothing is required. To facilitate heat release, an air-ventilated jacket has been developed and tested in three experiments. - The first one was carried out in the laboratory on four subjects wearing Nuclear, Bacteriological and Chemical clothing who were to perform light work for 8 hours (Tair: 45°C). The tolerance time was 32 minutes without ventilation, and more than 8 hours with body ventilation (200 L/min at 23°C). - The second one was carried out in the laboratory on 3 subjects wearing a “vinyl taped” suit that was completely impermeable to water vapor. The subjects walked on a treadmill, corresponding to 35 % of their VO2max in a 35°C environment (30 % humidity). The tolerance time was 0 hours 29 minutes without ventilation, and 2 hours 01 minutes with body ventilation (200 L/min at 23°C). - The third one was carried out on 4 decontaminators wearing “vinyl taped” suits for work in a nuclear environment (air: 30°C, humidity: 50 %). The tolerance time was 39 minutes without ventilation, and 1 hour 38 minutes with body ventilation (200 L/min at 28°C). In conclusion: Body ventilation is an effective means for working in a hot environment for subjects wearing protective clothing.
The Function of Semipermeable Membrane in Cold
Authors: Anttonen HP , Hiltunen EV , Virtanen JT
Published: March 2009

In a cold winter climate, functional clothing should offer protection against external inconveniences such as rain, cold and wind. At the same time, clothing should transmit sweat produced by the human body during hard work. Semipermeable membranes offer one solution to this problem. The function of multilayer winter clothing with different surface materials has been studied in different environmental conditions (+35 to -25 °C, 1 to 8 m/s) with a skin model in static and dynamic situations and with a sweating cylinder in a climatic chamber. The semipermeable membrane increases the total thermal resistance of winter clothings 10 to 25 % in dry conditions and 5 to 25 % below freezing point in sweating conditions. The water vapour transmission is 15 to 45 % lower when using semipermeable membrane. However in calm and cold conditions the membranes have no effect on total heat flux during sweating.
Anthropometric Analysis of Fit Problems in Chemical Protective Gloves
Authors: Tremblay JF , Crown EM , Rigakis KB
Published: March 2009

This paper demonstrates the usefulness of anthropometries in analyzing sizing problems found in commercially available chemical protective gloves for agricultural workers and makes recommendations for the design of better fitting gloves. The Engineering Anthropometric Clothing Design Model served as the framework for this research.

Because no data on the hand dimensions of agricultural workers were available an anthropometric survey was conducted of 380 Alberta grain farmers who handle pesticides. Nineteen hand dimensions were measured for each subject. When compared to military populations, the hand circumference of agricultural workers was found to be significantly larger.

A smaller sample of farmers who were representative of the agricultural population evaluated the static and dynamic fit of four glove types. Through this evaluation several major problems in the design of the gloves were identified. To improve the fit of chemical protective gloves for agricultural workers, the length of fingers need to be shortened and the thumb position relocated.
Protective Clothing Program Management
Authors: Wiernicki C
Published: March 2009

Managing the protective clothing and equipment program at a large production facility is a complex task. This paper describes the various components of the protective clothing program at a large facility. The author draws on his experience in managing the personal protective clothing and equipment program at a facility employing over 6,000 people with potential exposure to various hazards including particulates, solvent, acids and bases, molten metals, radiation, heat stress, and electricity. Proper protection from these hazards requires many types of protective clothing and a program to manage their proper use and effectiveness. Effective program management must include all of the following elements: a written program designating responsibility to a qualified person, personal protective equipment specifications, review of supplier facilities, interaction with vendors, Purchasing Department involvement, proper handling of deliveries and storage in the Supply Department, end user training, quality control testing, program audits and a feedback loop. The person having overall program responsibility must be knowledgeable about potential workplace hazards, personal protective clothing and equipment materials, permeation theory, quality control and possess strong communication and interpersonal skills. Clothing and equipment specifications should be performance oriented.
Developing and Selecting Test Methods for Measuring Protective Clothing Performance in Chemical Flashover Situations
Authors: Stull JO , Veghte JH , Mann PC , Storment SB
Published: March 2009

A number of chemical protective suits have been developed to provide a wide range of chemical resistance, durability relative to physical hazards, and limited resistance to ignition. Vapor-protective and liquid splash-protective suits compliant with NFPA 1991 and 1992, respectively, require primary materials (garment, visor, gloves, and boots) to resist ignition and provide self-extinguishing properties. While this requirement is designed to limit the use of inherently flammable materials in the construction of chemical protective suits, it does little to address a major concern to emergency responders - the rapid combustion or flash of a flammable chemical atmosphere. The ability of the chemical suit ensemble to protect under these circumstances remains uncertain without tests to demonstrate suit performance in a simulated chemical flashover.

This study involved development and selection of test methods to measure chemical protective suit performance in chemical flash environments. This work supports the development of the new NFPA Standards for flash protective clothing. A two part approach was followed. This first involved selecting a test for materials which simulates the relatively short, but high temperature exposure of a chemical flash. This phase involved comparing material performance in flame resistance, thermal protective performance (TPP), radiant reflective, and small scale flash environment tests. The second part was aimed at conducting a whole ensemble test where the chemical protective suit was placed on a mannequin within an enclosed area which was then filled with propane and ignited. This test was developed such that temperatures measured inside the suit can determine the extent of protection offered by the ensemble.

The resulting overall condition of the suit is also a recommended means for assessing performance.
Assessment of the Potential for Reducing Occupational Injury through Protective Clothing
Authors: Laing RM , Burridge JD , Wilson CA
Published: March 2009

Evaluation of the performance of protective clothing systems needs to include epidemiological evidence of their effectiveness. Using New Zealand's unique data bases on hospital admissions and on compensated claims for injury, this case series on hand and wrist injuries shows how the bases can be used as a powerful tool in establishing and maintaining injury prevention strategies. Of the hand and wrist injuries resulting in hospitalisation in 1988 31.0% were classified as work-related. The predominant features of the cases were the open wound (71.6%), involvement of freezing workers and butchers (12.9%), involvement of those aged 20–30 years (50.2%), males (91.1%) and Maoris (15.7%). Proposals are made for ways in which information from the data bases could be used.
European Directives and Standards Relating to Personal Protective Equipments
Authors: Mayer A
Published: March 2009

The European Economic Community (EEC) adopted measures with the aim of progressively establishing an internal market by 31.12.92 comprising an area in which the free movement of goods, persons, services and capital is garanteed. The free circulation of products is to be achieved through the elimination of technical barriers to trade, taken into account a high level of protection of the workers on the basis of the “New approach to technical harmonization and standards”. Directives (Laws) in this field contain only essential safety requirements and technical details are left to European standardization organizations. In the field of Personal Protective Equipment two Council Directives were adopted in December 1989. The first one is related to the use by workers and the second one to their design. In the latter, three certification procedures are defined that correspond to the levels of danger against which the PPE's are intended to protect. For most PPE's, a type-examination certificate awarded by an approved inspection body is required. Currently there are 190 standards being worked out to accompany this regulation work.
Water Column Toxicity from Contaminated Marine Sediments: Effects on Multiple Endpoints of Three Marine Species
Authors: Burgess RM , Comeleo R , Tagliabue MD , Sheehan KV , Kuhn A , Phelps DK
Published: March 2009

Water quality monitoring programs often include toxicity testing of ambient waters with the assumption that observed toxicity is due to existing anthropogenic discharges. These assessments rarely consider the potential that water column toxicity may originate from contaminated sediments. The objectives of this study were to (a) demonstrate that contaminated sediments can cause measurable water column toxicity and (b) illustrate the utility of short-term marine toxicity tests in these assessments. Clean overlying seawater was exposed to five marine sediments, representing a wide range of contamination. To determine if sediment-associated contaminants were released into the water column in toxic concentrations, water column toxicity was measured using three marine toxicity tests: the red algal, Champis parvula, reproduction test; the echinoderm, Arbacia punctulata, fertilization and development tests; and the mysid, Mysidopsis bahia, survival, fecundity, and growth test. Significant water column toxicity was observed, with Champia exhibiting the greatest sensitivity followed by Arbacia, and Mysidopsis. The most sensitive endpoints were reproduction and development. Exposure to New Bedford Harbor (USA) sediments caused the greatest water column toxicity while the relatively uncontaminated sediments elicited no detrimental effects. The approach used in this study demonstrates that contaminated sediments do have the potential to cause water column toxicity and that marine water column toxicity tests are sufficiently sensitive to detect this toxicity. In order to determine the contribution of the various sources of contamination to total water column toxicity, the data generated using this approach and other pertinent site information (hydrodynamic models, effluent and receiving water toxicity) can be integrated into a water column toxicity model.
Toxicity of Ambient Waters to the Estuarine Mysid, Mysidopsis bahia
Authors: Khan AA , Barbieri J , Khan SA , Sweeney FP
Published: March 2009

Many studies have investigated the toxicity of ambient waters of the Arthur Kill (NJ) to a variety of aquatic organisms. Most of these studies, however, have investigated acutely toxic effects only. Few studies have examined sublethal effects of the waters of Arthur Kill.

The present study investigated sublethal effects of ambient waters of the Arthur Kill to the estuarine mysid, Mysidopsis bahia. Three different sites were evaluated for effects on survival, growth and sexual maturity. Site one is upstream of the wastewater discharge from a large power plant. Sites two and three are one and two miles downstream of the discharge from the power plant, respectively. Water from Manasquan (NJ) inlet was used as the control for the study. The study was performed three times during a 3-month period.

The method for the study was based on recommendations of the manual “Interim Chronic Toxicity Testing Methodologies For Use in the New Jersey Pollutant Discharge Elimination System Permit Program, Version 1.0.”

Results indicate that survival was not affected in any of the sites investigated. Growth of mysids exposed to the upstream site was significantly reduced, as compared to controls, in all three tests. Growth of mysids exposed to water from sites two and three did not show any adverse effects in any of the three trials. Sexual maturity was adversely affected in mysids exposed to waters from sites two and three as compared to the controls. Sexual maturity in mysids exposed to water from site one was not significantly different from those in the controls.

Results from this study will contribute to the database on the ambient water quality of the Arthur Kill. The study clearly demonstrates the applicability of short-term screening toxicity tests as a simple tool for detecting ambient water quality. In addition, this study utilizes sexual maturity as a sublethal endpoint rather than fecundity for Mysidopsis bahia, representing a new means of including both sexes in reproductive toxicity.
Validation and Upgrade of a QSAR Study of the Toxicity of Amines to Freshwater Fish
Authors: Newsome LD , Johnson DE , Nabholz JV
Published: March 2009

Further development of a quantitative structure-activity relationship (QSAR) relies on a broader variety of chemical structures without loss of statistical robustness. Newsome et al.1 (1990) showed that a QSAR can be applied to a discrete class of amines to predict fish acute toxicity: log 1/LC50 = 0.70 log P −0.85 EQ. 1 (n = 41;r2= 0.84; s = 0.56)

A reevaluation of the amine class was performed to include more compounds and species. This study includes data for a variety of freshwater fish species and 20 acyclic and cyclic, mono- and diamines. The study extends the QSAR for predicting fish acute toxicity to a broader set of amine structures: log 1/LC50 = 0.673 log P -−0.81 EQ. 2 (n = 61;r2 = 0.86; s = 0.53)

The limitations of this QSAR as well as any outliers were examined.
Experiences in the Automation of Mechanical Testing
Authors: Gebhardt P
Published: March 2009

To be competitive, mechanical testing has to be automated to a high degree, up to ghost shift if possible. To effectively automate the laboratory, certain rules have to be followed. Mechanical testing systems are no longer laboratory machines, but have to be thought of as production systems. The new European Standard, EN 10002, is taking computerized automated testing into consideration.

Automation has to fit into the strategic objective of the company. This means that management has to promote the project.

As not only testing is concerned, a group of experts have to cooperate. The following disciplines are involved and have to be coordinated: Testing, Specimen Preparation, Process Control, Laboratory Data Management, Maintenance, Employees, and Safety. An example is shown in Mechanical Testing and Laboratory Automation in an Integrated Steel Mill.
Measurement, Control, and Data Processing Techniques in the Automation of Mechanical Testing
Authors: Mumford PM
Published: March 2009

Automation of mechanical testing began about 20 years ago with the addition of computers to provide automatic data acquisition and reduction for tensile tests. This paper will review developments in automated testing, with attention to some particular areas of interest or concern.

The computer, as a testing system component, offers great utility in automation of the testing process. Not only does the computer handle data acquisition and reduction, but also performs data storage and testing machine control functions.

The interface devices that allow the computer to access force and extension measurements and to control the loading process have improved many fold, and some new measurement devices, such as electronic calipers and optical extensometers, have been introduced.

Much progress has been made in algorithms and mathematical models for analysis of the data collected during the test. Particular attention will be given to modeling the data storage.
Peroxidase Activity as an Indicator of Sublethal Stress in the Aquatic Plant Hydrilla Verticillata (Royle)
Authors: Byl TD , Klaine SJ
Published: March 2009

This study examines the utility of plant peroxidase (POD) activity as a biochemical indicator of chemical stress in the aquatic plant Hydrilla verticillata (Royle). Plants were raised in 10% Hoagland's solution augmented with 200 mg NaHCO3/L. The plants were exposed to concentrations of exponential increment of Cu2+ or the sulfonylurea herbicide, sulfometuron methyl, (methyl 2-[[[[(4,6-dimethyl-2-pyrimidinyl) amino]-carbonyl] amino] sulfonyl] benzoate), also known by the trade name OustR. After seven days of exposure the plants were harvested, macerated, and the POD extracted with salt solution. POD was measured by a spectrophotometric assay. There was a significant increase in POD activity after exposure to sublethal concentrations of Cu2+ or Oust. This increase in POD activity was dose dependant and concomitant with a decrease in root and shoot elongation. Plants exposed to 1 mg/L Cu2+ resulted in a 1.75-fold increase over the controls in shoot POD activity. Plants treated with 1 mg/L Oust resulted in a 1.5-fold increase in shoot POD activity over the controls, yet no necrosis was visible after seven days. These results indicate that measuring the saltextractable POD activity has great potential as a biochemical indicator of sublethal stress in the aquatic plant H. verticillata.
Ecotoxicological Assessment of Toluene and Cadmium Using Plant Cell Cultures
Authors: Reporter M , Robideaux M , Wickster P , Wagner J , Kapustka L
Published: March 2009

Cell suspension cultures from a variety of plant species can be grown from callus for use in ecotoxicological testing. The effects of toluene and cadmium on plant cell growth were investigated. The accumulation of cadmium in the soluble cell “cytoplasmic” and in the cell residue compartment in two cell types was also verified by elemental analysis using inductively coupled atomic plasma emission spectroscopy (ICPAES). Plant cell cultures in suspension can be most useful in tracing the fate of labeled toxic chemicals and in an isolated environment. Both tracer fate tests and toxicity tests with plant cell cultures can then aid in the optimal design of more costly experiments with whole plants. Callus and suspension cultures can be maintained with their individual characteristics through many cell transfers. Alternately, these characteristics can be preserved by placing appropriately treated cells at liquid nitrogen temperatures. A majority of these cultures can be grown in standard media that can be made in individual labs or purchased from regular suppliers. The use of standard cultures make it possible to address comparability for routine ecotoxicological testing of chemicals between different labs.
Identification of Aneuploidy-Inducing Agents Using the Wheat Seedling Assay
Authors: Sandhu SS , Dhesi JS , Gill BS
Published: March 2009

A short-term assay using Chinese Spring wheat for detecting induced aneuploidy and/or clastogenicity is described. Seeds of virescent wheat (v1v1) are treated with a test agent. The appearance of white sectors (v1v1v1) or green sectors (v10) on the virescent leaves indicates the gain or loss of a chromosome or a segment of a chromosome-bearing v1 allele. Three test chemicals, chromium trioxide (100 to 5000 (μg/mL), chromium dichromate (500 to 5000 μg/mL), and cyclophosphamide (100 to 1000 μg/mL) produced a dose-related positive response for chromosome aberrations in this assay.
Damage-Based Assessment of Stress Corrosion Performances Among Aluminum Alloys
Authors: Lukasak DA , Bucci RJ , Colvin EL , Lifka BW
Published: March 2009

At Alcoa Laboratories the breaking load test was developed to provide a more discriminating accelerated laboratpry practice for rating stress corrosion cracking (SCC) performances of relatively resistant aluminum materials. The method involves residual strength measurements from tensile bar specimens previously exposed to sustained tensile stress in a corrosive medium. The degree of SCC degradation is measured by comparing the specimen postexposure strength with the original tensile strength (no exposure); the greater the strength loss, the more harmful the attack. In contrast to the more traditional pass/fail life testing approaches, the breaking load method enables numerical differentiation among materials and precludes long waiting periods for specimens to fail in the environment. In addition, the breaking load method provides descriptors amenable to flaw size and probabilistic fracture mechanics interpretations, thereby enabling expression of SCC ratings in meaningful terms of crack initiation and growth kinetics. Conventionally used descriptors of SCC behavior (e.g., time to failure, percent survival, threshold stress, KIscc) are influenced to varying degrees by both the strength and toughness of the test material and the conditions of the testing (e.g., specimen geometry and loading method). The damage-based evaluation of breaking load data is advantageous in that potential biases in SCC performance ratings caused by material property differences and specimen size effects can be normalized.

Extensive work to refine and demonstrate the usefulness of the breaking load practice for aluminum SCC evaluation was completed in 1984 under a NASA-Langley contract to Alcoa Laboratories. Much of the development work to this point was largely based on single-lot evaluations of AA7075 plate/temper variations. Since this time, Alcoa has adopted the breaking load method in alloy development, and this paper provides new additional data to illustrate the general applicability of the approach. Included in these results are posttest fractography and fracture mechanics analysis, illustrating advantages of damage-based interpretation over conventional SCC descriptors developed from smooth and precracked (DCB or WOL-type) specimen tests. The significance of the findings is discussed in terms of general material selection guidance related to durability and damage-tolerant structural design objectives.
Corrosion Fatigue Crack Growth Rate of Aluminum-Lithium Alloy Sheet and its Weldment
Authors: Lin CS , Krams WE
Published: March 2009

A high-speed welding process has been successfully developed for aluminum-lithium alloy joints, the product of which demonstrates a substantial weight-saving potential for aircraft, spacecraft and missile applications. Because dynamic environmental effects, interpreted as corrosion-fatigue crack growth, can lead to a reduction in the strength of airframe, engine, and accessory structures, the corrosion-fatigue cracking susceptibility of aluminum-lithium alloy and its weldment must be understood by aerospace designers if further consideration is to be given to this material.

Corrosion-fatigue crack growth in an optimally welded aluminum-lithium alloy joint was investigated at ambient temperature by alternate immersion in a 3.5% NaCl solution and air. The corrosion-fatigue crack growth rate (da/dN) was evaluated by studying precracked compact-tension specimens and then correlating the results with the applied cyclic stress intensity range (ΔK). The crack and fracture morphology exhibited by tested specimens were investigated with scanning electron microscopy and Auger electron spectroscopy. Metallurgical factors, such as linear grain-boundary precipitation and spherical general precipitation at the crack tip area, were analyzed for the development of a corrosion-fatigue cracking mechanism.
Potentiometric and Potentiostatic Determination of the Corrosion Rate of Welded 2519 Aluminum Alloy
Authors: Sonnino CB , Ford T , Vanark V
Published: March 2009

A new aluminum alloy, designated 2519, was developed for superior stress corrosion resistance, but the galvanic corrosion characteristics of 2519 weldments are not well understood. This study demonstrates that the weld metal is cathodic to the heat affected zone (HAZ) and to the parent metal. The potential differences are smallest for the parent metal/HAZ couple and highest for the HAZ/weld metal couple. The results of the study agree with the corrosion relationship predicted by the potentiostatic results. The study concludes that corrosion protection of the welded structure is necessary for efficient application of 2519 aluminum weldments.
The Scanning Brookfield Technique of Low-Temperature, Low-Shear Rheology -- Its Inception, Development, and Applications
Authors: Selby TW
Published: March 2009

The development of the Scanning Brookfield Technique (SBT) has generated new understandings of the rheology of automotive lubricants at low temperatures, particularly in engine oils and even more particularly in regard to the phenomenon of air-binding, which is believed caused by oil gelation. The latter phenomenon has been directly implicated in the pumpability failure of engines in the field and in cold-room simulation.

This paper first traces the prior studies and use of the Brookfield Viscometer at low temperatures -- work which generated low-temperature information on lubricants and methods ultimately leading to the development of the Scanning Brookfield Technique (SBT) and the application of this technique to the detection of the presence and severity of gelation at lower temperatures of automotive operation. The SBT has shown close correlation with the Pumpability Reference Oils (PROs) used in the ASTM engine pumpability study and detected significant gelation in all known field- or engine-failing oils.

The most recent studies generated by the SBT show that the technique permits the measure of new criteria of gelation, two of which are 1. Gelation Index, a measure of maximum gelation severity closely correlated with the yield stress of a lubricant, and 2. Gelation Temperature, the temperature at which the Gelation Index is generated.
Lube Manufacturing Technology and Engine Oil Pumpability
Authors: Rossi A
Published: March 2009

Lube basestocks are manufactured by four process technologies, which are a series of physical and chemical operations. This separation science determines many of the chemical and physical properties that basestocks exhibit in engine oils. The four technologies can produce basestocks with the same physical properties -- viscosity, viscosity index, and pour point -- and yet are desirable mixtures of different hydrocarbons. Basestocks with the same physical properties, but manufactured by different technologies, need not have the same wax compositions or show the same low temperature engine oil pumpability properties.
Compressive Strengths and Bond Strengths of Portland Cement-Lime Mortars
Authors: Melander JM , Conway JT
Published: March 2009

ASTM Standard Specification for Mortar for Unit Masonry (ASTM C 270) requires mortar to be specified either by proportion specifications or property specifications. For portland cement-lime (PCL) mortars, it has been suggested that a significant difference exists between the properties of mortars mixed according to the proportion specifications and the requirements of the property specifications.

This paper presents data confirming that compressive strengths of PCL mortars according to current proportion limits do vary significantly from present property specification requirements. Alternative proportions that would bring the performance of cement-lime mortars more in line with the property specification requirements can be formulated based on the data.

The paper also investigates the relationship of portland cement content to flexural bond strength development of cement-lime mortars as obtained from tests conforming to UBC Standard 24-30. A mathematical model of the relationship is proposed and compared to additional experimental data.
Laboratory Study of the Corrosion of Steel Studs and Screws Used in Masonry Walls
Authors: Kudder RJ , Slater JE
Published: March 2009

Steel-stud/brick-veneer walls utilizes metal studs as the backup for brick masonry veneers. Screws are used to secure a tie or anchor to the stud. This system is unique in masonry construction because the engagement of the threaded shank of the screw into a cold-formed steel stud is relied upon to laterally secure the exterior masonry wythe. The generally successful use for the traditional cavity wall ties and anchors mays not necessarily apply to steel-stud/brick-veneer walls because of this reliance on the screw threads. The environment in a masonry cavity may support corrosion. The effects of corrosion on the load capacity of the screw is a concern associated with this masonry system. This paper discusses an laboratory study of the tensile capacity of screws in metal studs, and the change in capacity over time when these metals are in a warm, humid environment.
Variables Affecting the Strength of Masonry Mortars
Authors: Wright BT , Wilkins RD , John GW
Published: March 2009

Masonry cement mortars with additives which entrain various levels of air as well as mortars containing lime were evaluated. A mathematical model was developed describing brick-to-mortar bond strength. Lime mortars, prepared as specified by ASTM with higher proportions of portland cement, provided higher bond strengths and higher compressive strengths compared to masonry cement mortars. When prepared with the level of portland cement typical of masonry cement mortars, lime mortars had comparable bond strengths but weaker compressive strengths at similar air content. A one percent increase in Portland cement content increased the bond strength four times as much as reducing the air content by 1%. Lime did not provide increased bond strength. The higher bond strengths achieved with Type S portland cement/lime mortars over Type N are a direct result of higher portland cement content.
Slurry Walls-Construction Quality Control
Authors: Tamaro GJ , Poletto RJ
Published: March 2009

Structural slurry walls have become a standard method for the construction of deep underground structures in the United States. Structural slurry walls have been excavated to great depth and have been installed to plan dimensions from approximately 10 meters in diameter for circular shafts to hundreds of meters for walls for tunnels or large commercial basements. Slurry walls have been installed through a variety of difficult geological formations with varying success, and have been used as temporary walls, permanent walls, water cutoff walls, load bearing elements or in lieu of underpinning.

Currently there are no United States standards for the design and/or construction of slurry walls. Government agencies, private consultants, contractors and trade groups have prepared and, from time to time, published and distributed specifications for the construction of slurry walls [1]. These specifications vary in degree of complexity and quality standards. Some specifications place excessive emphasis on the preparation and control of bentonite slurry used for excavation, with insufficient emphasis placed on quality control of the tremie concrete placement or requirements for the finished product. This paper will discuss the slurry wall construction process, identifying those areas which require special scrutiny by the contractor and owner.
USA Practice Slurry Wall Specifications 10 Years Later
Authors: Millet RA , Perez J-Y , Davidson RR
Published: March 2009

Ten years earlier the authors prepared a paper on the then beginning state of practice regarding slurry wall specification in the USA. Changes (or lack thereof) and developments in the basic building blocks of specification criteria for the two types of walls constructed by the slurry wall technique; i.e., structural diaphragm walls and cutoff walls are reviewed. Specific recommendations and overview guidance for specification content are made for each wall type. Conclusions are presented concerning the present needs and likely future developments in this rapidly expanding specialty construction field.
Concrete Slurry Wall for Temporary and Permanent Foundation Wall at Gallery at Harborplace — Baltimore, Maryland
Authors: Gifford DG , Wheeler JR
Published: March 2009

The selection and installation of a concrete diaphragm wall by the slurry trench process simplified construction and provided high quality underground space for a 5-level garage in Baltimore, Maryland. The tieback supported wall retained the adjacent streets and utilities with surface settlement ranging from 0.5 to 0.75 in. (12.7 to 19.1 mm). Groundwater levels were maintained and seepage into the excavation was reduced to about 5 gallons per minute (0.32 L/s). Geotechnical instrumentation data confirmed satisfactory performance of the wall and tieback system; instrumentation was also key during assessment and resolution of construction problems which led to additional lateral displacement of the wall.
Materials for Slurry Walls in Waste Chemicals
Authors: Khera RP , Tirumala RK
Published: March 2009

The majority of test data indicate that the hydraulic conductivity of soil-sodium bentonite mixtures increases several folds with many of the chemicals found at waste disposal sites. This investigation is on mixtures consisting of calcium bentonites from four different sources, cement, slag, and fly ash using flexible wall permeameter. The mix with calcium bentonite from Greece yielded hydraulic conductivity values which were equal to or lower than 10-7 cm/s. With water and organic chemicals (aniline 5,000 ppm, phenol 5,000 ppm, toluene 500 ppm) the soil mix showed a decrease in hydraulic conductivity. Over a 40 day period the hydraulic conductivity decreased from about 10-7 cm/s to 10-9 cm/s. The rate of decrease in hydraulic conductivity with phenol was somewhat slower. The hydraulic conductivity did not increase with time with any of the chemicals.
Seepage Cutoff Wall for Mud Mountain Dam
Authors: Davidson RR , Levallois J , Graybeal K
Published: March 2009

Monitoring of instrumentation of the 50-year old Mud Mountain Dam indicated to the U.S. Army Corps of Engineers (Seattle District) that the core of the 120-meter high earth-rockfill dam possessed defects that could lead to a potential piping failure. Therefore, a concrete cutoff wall was constructed using hydrofraise slurry wall construction techniques to correct this problem. During construction of the slurry wall, severe slurry losses and cracking of the dam occurred. A sophisticated recompression grouting program was implemented to fill existing openings and recompress the distressed core material to prevent hydraulic fracturing by the head of slurry in the trench. Once the grouting program was finished, the cutoff wall was completed without incident to a new world record depth of 122.7 meters.
The Construction of “Thin” Slurry Walls and the Supporting Liquid Slurries Used
Authors: Breek HCM
Published: March 2009

A method to make a thin slurry trench or wall in the ground, based on the US patent number 4,877,357, whilst using different supporting fluids.

The slurry trench or wall will be formed into the ground by driving a beam section and simultaneously and entirely filling up the trench, formed by soil displacements with a supporting fluid. The wall is formed by driving a steel beam sectional to the required depth after which it is subsequently pulled out of the soil with a vibrating movement, which is obtained by delivering blows to the beam at a suitable frequency, by vibrator or vibratory hammer. Whilst the beam is extracted, sufficient supporting fluid is supplied to fill up the trench/wall formed by the beam.
Quality Control in Construction of Structural Diaphragm Wall Joints
Authors: Lee K-H , Ou C-D , Tsai K-W
Published: March 2009

Diaphragm wall with leaky or defective joints have been identified as one of the main reasons that lead to ground loss and associated structural distress of adjacent buildings. In recent years, improvements in joint details and construction procedures have been proved successful in achieving watertightness requirements of structural diaphragm walls for deep excavation projects in Taiwan. The various factors which lead to leaky or defective joints and possible preventive measures are addressed.
National Cost of Damage to Infrastructure from Highway Deicing
Authors: Menzies TR
Published: March 2009

This paper draws on findings from a study of the full cost of highway deicing salt by a National Research Council committee. Cost estimates are presented for bridges, other highway components, and parking structures. Summation of the more reliable cost items, for which supporting data are dependable and relatively complete, suggests a national cost of $200 million to $500 million per year. Inclusion of cost items based heavily on committee judgment suggests a national cost of about $400 million to $900 million per year.
Evaluation of an Atmospheric Corrosion Rate Monitor
Authors: Haynie FH
Published: March 2009

An Atmospheric Corrosion Rate Monitor (ACRM) with an improved polarization resistance type sensor design was evaluated. A year of hourly average sensor data were correlated with simultaneously collected environmental data and corrosion data measured by mass loss and a rain runoff technique. The study was done at an exposure site in the Research Triangle Park, NC. Sensor responses to wetness were reproducible. Although the sensors were sensitive enough to detect environmental changes other than wetness, these changes are apparently affecting cell resistance rather than polarization resistance. The ACRM may be modified to measure polarization resistance.
Improved Rail-Fastener Insulation for Stray-Current Control
Authors: Galler D , Todd PL
Published: March 2009

In North America, dc powered transit systems use running rails for negative return of traction current. Insulated rail fasteners are used to electrically isolate the rails from earth and structures in order to minimize stray current and the resultant corrosion. The insulating surfaces of the rail fastener can become wet and contaminated in service so that leakage current paths develop. This paper describes the development and testing of improved rail fastener insulation.
Impregnation of Concrete with Corrosion Inhibitors
Authors: Berke NS , Dallaire MP , Weyers RE , Henry M , Peterson JE , Prowell B
Published: March 2009

Corrosion of steel in concrete is a major problem in the U. S. infrastructure. Approximately half of the bridges in the interstate highway system are in need of repair, and a significant cause is the corrosion of the embedded steel due to chloride ingress. A similar problem is found in parking structures throughout the northern regions of the United States due to deicing salts brought in from automobiles.

As of now the only commercial means of arresting corrosion without replacing concrete is the application of cathodic protection. Calcium nitrite has been shown to be an effective corrosion inhibitor when admixed into plastic concrete. In this paper an experiment to impregnate a bridge deck and support column with calcium nitrite is discussed.

Two methods were used to impregnate the concrete with calcium nitrite. The first involved drying a bridge deck by heating it above the boiling point of water, and then slowly cooling to ambient temperature to avoid thermal and drying shrinkage cracking. The deck was then successfully impregnated with liquid calcium nitrite.

The column was impregnated by removing delaminated concrete and drilling holes. A calcium nitrite rich latex modified grout was placed in the drill holes and a calcium nitrite rich latex modified concrete was produced to replace the removed concrete. Nitrite migration into the sound concrete left in place is to be measured over time.

Corrosion rates determined by polarization resistance, and corrosion potentials were measured before the above processes were performed. The steel was definitely corroding in some areas and the corrosion behavior is to be monitored over time.