bluuebunny/crossref_metadata_2025 huggingface dataset:
The Northwest Wall Moisture Study: A Field Study of Moisture in the Exterior Walls of New Northwest Energy-Efficient Homes
Authors: Tsongas GA
Published: March 2009

The purpose of this study was to find out whether building the exterior walls of new homes to energy-efficient standards with more insulation (at least R-19) and an air/vapor barrier causes unacceptably high levels of moisture or related problems within walls. This was to be determined by field inspection of such homes and openings in their walls. An additional purpose of the study was to determine if any other type of moisture-related problems have occurred in the heavilyinsulated, relatively airtight new homes. Fifty test homes were located in the Seattle-Olympia area, sixteen along the rainy Washington coast, and twenty in the cold Montana region. The exterior walls of the 86 newly constructed homes were opened between January and March 1987 under the worst expected conditions and inspected for signs of moisture, moisture accumulation, or moisture damage. Measurements of the moisture content of selected wood members within the wall cavities also were made. Over half of the test homes had at least one wall wood member with over 20% moisture content. Half of the mud (sill) plates and over one-third of the sheathing were equal to or above 20% moisture content. Whether the walls will dry out sufficiently during warmer weather in order to avoid wood decay and consequent structural damage is unresolved. In addition to the wall cavity moisture problems, numerous moisture-related problems were observed within the homes, primarily because of inadequate moisture control. The results and conclusions of the field study are described in detail. Future research needs also are discussed.
A Comparison of Two Techniques for Monitoring the Field Thermal Performance of Roof Systems
Authors: Courville GE , Childs PW , Moazed AR , Derderian GD , Stewart GD , Shu LS
Published: March 2009

Two independent techniques, one intrusive and one non-intrusive, for monitoring the thermal performance of in situ roof systems are compared. The intrusive technique requires thermocouples on inside and outside surfaces of the roof system and a heat flux transducer (HFT) embedded in the system. The non-intrusive procedure has the same thermocouple placement and a series of HFTs on the inside surface of the deck. The crucial difference in the methods is in the HFT placement and the technique for HFT calibration. Results of a one-year field study using both methods on the same roof assembly are described. The roof assembly is a built-up roof with molded expanded polystyrene (EPS) insulation above a metal deck.
A Comparison of Two Independent Techniques for the Determination of In Situ Thermal Performance
Authors: Courville GE , Desjarlais AO , Tye RP , McIntyre CR
Published: March 2009

A parallel experiment has been performed on an insulated roof system installed in the Roof Thermal Research Apparatus at Oak Ridge National Laboratory. Separate sections of a 1.2 by 2.4 m test panel were evaluated for nine months using two different heat flux transducer (HFT) instrumentation packages, with the data being treated independently. The paper discusses the instrumentation packages, sensor calibration procedures, and data collection and analyses methods, highlighting the differences between the independent techniques. A comparison of the independently derived thermal performance results is presented. The comparison includes a discussion of the HFT test techniques for determining the in situ thermal performance of insulated building components. Limitations of these procedures are also detailed.
Use of Two Heat Flow Transducers for Transient Thermal Measurements on Porous Insulating Materials
Authors: Langlais C , Boulant J
Published: March 2009

A method for measuring the apparent thermal conductivity of fibrous insulating materials under non-steady-state conditions is presented. The apparatus comprises one specimen and two heat flow transducers.

Equations describing the variation of heat flow as a function of time and position are given. These equations are used to derive thermal transient properties from the heat flux measured on the cold and hot sides of the specimens.

Finally, measurements on a variety of fibrous insulating materials are presented. These measurements show good agreement between the apparent thermal conductivities measured under transient and steady-state conditions. A significant reduction in test times compared to classic measurements with a single heat flow transducer apparatus was obtained.
Modeling of Thermal Resistance Test Configurations That Use Thin Heaters
Authors: Yarbrough DW , McElroy DL , Graves RS
Published: March 2009

The usefulness of a large unguarded thin screen heater as an integral part of a thermal resistance measurement apparatus for insulations has been demonstrated. Thermal modeling of existing and proposed test configurations can be used to establish applicability. HEATINGS, a general purpose conduction program, has been used to obtain the temperature distributions encountered in linear and radial heat flow testers with thin heaters.

Thermal simulations of the existing screen tester have been used to determine the effects of specimen thickness and thermal resistance on measurement errors. Simulation results were obtained for test configurations in order to provide a basis for design improvement (i.e., the effect of increasing levels of edge insulations on the apparent thermal conductivities obtained with the tester).

The extent to which limited edge guarding extends the operating range of a flat tester has been examined using HEATING5. A gradient guard along the edge of the specimen in the tester reduces the measurement errors due to edge heat loss. The improvement predicted by HEATING5 in measurement accuracy of a thin heater apparatus due to edge guarding that approximately matches the mean temperature on the edges with the mean temperature in the metering section has been examined experimentally.
Importance of Radiation in Transient Tests of Fibrous Insulations
Authors: Thomas JR
Published: March 2009

Transient tests of fiberglass insulation were examined theoretically to determine effects of radiation heat transfer. It was found that radiation dominates the heat flow process during the first several minutes, and that waiting times on the order of 20 to 30 min are necessary to achieve results consistent with steady-state tests. This time could be reduced if samples are oven-dried before testing.
Optically Thin Fibrous Insulations
Authors: Fricke J , Caps R , Hümmer E , Döll G , Arduini MC , De Ponte F
Published: March 2009

The thermal conductivity of low density organic fiber boards has been measured using various guarded hot plate and heat flow meter apparatus. The data are analyzed with a three-flux representation for the radiative heat transfer and compared with extinction results from infrared optical measurements and scattering theory calculations.
Minimum Life-Cycle Cost Analysis of Residential Buildings for PC-Based Energy Conservation Standards
Authors: Tuluca A , Heidell J
Published: March 2009

The proposed “Energy Conservation Standards for New Federal Residential Buildings” are embodied in an interactive computer program which analyzes over 400 Energy Conservation Options (ECOs) for 9 housing types and 5 fuels across 1000 U.S. climate zones. The program uses Life-Cycle Cost (LCC) economic analyses in a two-step procedure to derive a result close to the “economic optimum”: (1) an initial Savings-to-Investment Ratio (SIR) ranking, followed by (2) a series of Net Benefit (NB) iterations. Consideration is given to the interaction between the set of envelope and the set of mechanical equipment ECOs.

The distinctive.feature of the LCC algorithm is that it simultaneously evaluates these two sets of ECO types, and in doing so it keeps active the entire list of energy conservation measures through-out the NB calculations. Envelope ECOs found to be ineffective at a certain combination of heating/cooling mechanical equipment efficiencies are re-examined every time equipment efficiencies change. In a new context of efficiencies, these envelope ECOs may become cost-effective. Similarly, envelope ECOs which were before cost-effective may lose this status. The same process applies to the LCC evaluation of equipment ECOs within a changing loads context.
Implementing Thermal Insulation Product Standards
Authors: Nelson BD
Published: March 2009

Product standards for residential thermal insulation were authorized by the Minnesota Legislature in response to the marketing of substandard insulation. In 1985 administrative rules established minimum standards for all residential insulation products sold or installed in the State. When possible, these requirements were based on industry consensus standards. The rules require manufacturers to file annual reports with the State, indicating that their products have been tested and meet the minimum standards. Manufacturers must also provide installation instructions to purchasers. Special testing provisions and installation instructions are required for insulations intended for use exterior below ground.

Manufacturers of insulation marketed in the State have been notified of this regulation. Filings of products are acknowledged by the State as being complete, or incomplete, with explanations as necessary. The State has published lists including products of 36 companies with completed filings and of those with filings in preparation.

Four areas have been particularly difficult in the design and implementation of this program. The first is deciding on equitable quality assurance requirements for manufacturers of insulation. A second is determining what products are acceptable for exterior foundation wall applications. Third is how consumers can identify which insulation products meet the standards. Finally, and probably most important, is how the installation of material can be improved so as to realize its full potential energy saving benefits.

The insulation manufacturing industry has been-very supportive of this program. In the first two years of its existence, the program has benefited both consumers and industry.
Corrosiveness of Residential Thermal Insulation Materials under Simulated Service Conditions
Authors: Sheppard K , Weil R , Desjarlais A
Published: March 2009

The corrosiveness of various residential thermal insulation materials was tested under simulated field conditions in a test wall structure. The test was conducted under controlled conditions typical of winter in the absence of a vapor barrier to create relatively severe moisture transport and possible condensation. The house-wall simulation was achieved by constructing a test panel containing 50 compartments into which various insulation materials were installed. The panel was located in an environmental chamber. The test samples included various cellulosic, glass fiber and rockwool insulations as well as sterile cotton as a control. Steel and copper coupons together with water-cooled copper pipes were embedded in the insulation and exposed for six months. It was found that moisture absorption by the insulation was the primary factor in causing corrosion but required that chemical activity from insulation components also be present. No corrosion occurred in the absence of insulation or in rockwool and glassfiber insulation. All cellulose insulations caused some corrosion; mostly this was minimal, but in a few cases severe pitting resulted. Such behavior of the cellulose did not correspond to previous laboratory test results in saturated insulation or leachants made from the insulation. However, laboratory testing of leachants made from some of the cellulose after the simulated wall test showed a change in pitting tendency, suggesting that time and/or exposure to moisture can change the corrosiveness. This should be further explored.
The Most Needed Building Foundations Research Products
Authors: Christian JE
Published: March 2009

This paper describes a research program targeted towards the significant potential for energy savings from improved residential building foundations design. A recent study at the University of Minnesota estimates that less than 5% of foundations in the present building stock are optimally insulated. In addition, this study indicates that the potential national savings from upgraded basements, crawl spaces, and slab-on-grade foundation systems in residential and small commercial buildings is about 0.5 quads/year (0.523 × 1018 J/year).

This research program is based upon a research needs assessment developed by the Building Foundations Research Review Panel. This panel was established by the U.S. Department of Energy (DOE) and Oak Ridge National Laboratory to assist in the formulation of DOE foundations research policy and the development of a technology transfer strategy to get this research to the marketplace. Half of the panel members are from private industry.

One of the first tasks the panel addressed was to formulate a prioritized list of building foundation research needs.

Building foundations research needs include: widescale dissemination of existing information on good practices for energy-efficient construction and retrofit, accurate characterization of the thermal properties of soils, validated foundation heat and mass transfer algorithms coupled into whole-building simulation models, an experimental data base from one or more well-characterized test sites, and design tools to effectively transfer the results of research into practice.
High-Temperature Calorimeter Performance Variable Study
Authors: Troyer RL
Published: March 2009

Oak Ridge National Laboratory with funding supplied by the Department of Energy sponsored the evaluation of a water calorimeter for thermal transmission testing of refractory fiber insulation using a ruggedness test. A round robin conducted on the calorimeter indicated that differences between laboratories are significant. The water calorimeter has several design characteristics that differ from other test methods. The energy transfer is measured by the increase in temperature of a constant water flow so the calorimeter is on the cold side and never exposed to high temperatures. With this test method the temperature difference across the sample is very large compared to some other instruments. In order to improve the test method a series of experiments was performed within a single laboratory to evaluate the sensitivity of the test method to deviations in standard practices. This experimental method is a ruggedness test, which is a statistical method of evaluating step changes while making multiple changes each test. Since this method is used for testing materials at different temperatures, essentially an independent ruggedness test was conducted at three temperatures. The factors evaluated included (1) emissivity of cold surface, (2) calorimeter to guard balance, (3) calorimeter to room temperature balance, (4) calorimeter water flow rate, (5) perimeter insulation, (6) type of hot side thermocouple, and (7) type of cold side thermocouple. Different factors were significant at different temperatures. Short and long term recommendations are given for improving the operation of the calorimeter.
On the Thermal Insulation of Outdoor Electronic Cabinets
Authors: Guglielmini G , Milano G
Published: March 2009

The thermal behavior of electronic cabinets for outdoor installation is analyzed. As the correct working condition of circuit boards requires a temperature-conditioned housing, the thermal design of the cabinet structure must be carefully foreseen from both the insulating and cooling point of view.

After a short review of some technical solutions for passively conditioned cabinets, an approximate physical model is presented that is able to simulate with a sufficient degree of generality the transient thermal behavior of the structure as a whole. Several examples of numerical solutions are reported relating to different kinds of cabinets with or without natural air ventilation. The effect of thermal storage inside the cabinet is analyzed, too.

The numerical simulations show that for this kind of application any thermal calculation procedure must take into account the transient effect in all structural components.
Heat-Insulating, High-Temperature Materials on Cenosphere Base
Authors: Ignaszak Z , Baranowski A , Hycnar J , Zak M
Published: March 2009

Cenospheres (microspheres) are silica-alumina fly ash lightweight fractions obtained from burning pulverized coal. These fractions are characterized by spherical particle shapes of 40 to 400 μm diameter (apparent bulk density 400 kg/m3). The thermal-insulation properties of microspheres are useful. A binder that ensures good strength and improves thermalinsulation properties of bonded materials is hydrated sodium silicate. These microsphere materials are characterized by: (a) apparent bulk density in the compressed state from 400 to 500 kg/m3, (b) compressive strength up to 6 MPa, (c) average mean heat capacity of 500 kJ/m3K at temperatures from 298 to 993 K, and (d) thermal conductivity in the range 0.13 to 0.38 W/mK at temperatures from 298 to 1273 K. The investigation made it possible to optimize the material composition for particular applications. Microsphere materials with silicate binders can be used in the building industry, in heating equipment, and in metallurgical and foundry work.
Effect of Water-Film Thickness on Tire-Pavement Friction
Authors: Kulakowski BT , Harwood DW
Published: March 2009

The results of an extensive experimental investigation of the thin water films of thickness less than 0.38 mm (0.015 in.) on the tire-pavement friction are presented. Both laboratory and full-scale field tests involving new measuring equipment were conducted, and a new device was developed for laboratory measurement of rubber-surface friction. Also, a new apparatus was built to measure thickness of thin water films formed on pavement surfaces. The results from the laboratory and field tests indicate that the tire-pavement friction can decrease significantly at very thin water films from 0.025 to 0.230 mm (0.001 to 0.009 in.). A quantitative measure of the effect of water-film thickness on tire-pavement friction is proposed. The effects of tire, vehicle speed, and pavement texture on pavement wetness sensitivity are also investigated.
A New Laser, Noncontact Method for Measuring Vehicle-to-Pavement Distance
Authors: Caussignac JM , Morel G , Charrier J
Published: March 2009

This paper describes a new laser technique for measuring displacement or the distance from a vehicle to the pavement. This noncontact method is based on the analysis of a nonfocused image of a laser spot by a matrix sensor. We show that the proportion of light energy received by the central pixel and the total energy received by matrix sensor depends on the distance to the pavement. The analog signal is digitized and treated by a computer. This technique is rapid and causes no disturbance to the pavement. The operating range, the resolution, and the height accuracy may be adjusted by changing either the geometric relationship of the different components of the apparatus or the focal length of the lens.
New-Generation Skid Testers for the 1990s
Authors: Wambold JC , Meyer WE , Henry JJ
Published: March 2009

Economical friction testers are needed which will generate more useful data than current testers, especially with the abolishment of the 88-km/h speed limit and the increasing use by automakers of antilock braking systems. Three basic methods designs for testers, the ribbed/blank-tire, the spinup, and the spindown, are evaluated. It is found that the two-wheel ribbed/blank-tire method can be used by existing testers to provide the optimum amount of data without mechanical modifications. The test-wheel spinup method, which obtains the skid number/speed relationship, is recommended for newly built testers.
Aircraft/Ground-Vehicle Friction Measurement Study
Authors: Yager TJ
Published: March 2009

Tests with specially instrumented NASA B-737 and FAA B-727 aircraft together with several different ground friction-measuring devices have been conducted for a variety of runway surface types and conditions. These tests are identified as part of Joint FA A/NASA Aircraft/Ground Vehicle Runway Friction Program aimed at obtaining a better understanding of aircraft ground handling performance under adverse weather conditions and defining relationships between aircraft and ground-vehicle tire friction measurements. Aircraft braking performance on dry, wet, snow-, and ice-covered runway conditions is discussed together with ground-vehicle friction data obtained under similar runway conditions. For a given contaminated runway-surface condition, the correlation between ground vehicles and aircraft friction data is identified. The influence of major test parameters on friction measurements such as speed, test-tire characteristics, type and amount of surface contaminant, and ambient temperature is discussed. The effect of surface type on wet friction levels is also evaluated from comparative data collected on grooved and ungrooved concrete and asphalt surfaces.
Equipment and Methods for Assessing Surface Characteristics of a Road Network
Authors: Jordan PG
Published: March 2009

A high-speed road monitor (HRM) has been developed for measuring road surface characteristics and road alignment. It simultaneously measures longitudinal profile, rutting, macrotexture, and road alignment while traveling in the normal traffic stream. Correlation coefficients exceeding 0.9 have been obtained between manual surveys of profile, rut, texture, and road alignment, and the corresponding HRM measurements. The relationship between surface data and road condition has been investigated, and change profile unevenness with time has been found to be a useful indicator of road deterioration. Other investigations particularly into ride have provided criteria for assessing the serviceability level of a road.

For routine use, a computer-analysis program has been developed to analyze the large volumes of data collected by the HRM. The paper describes the main elements of the program and concludes that the combination of equipment and analysis system provides a cost-effective surveying and assessment system for a primary road network.
Analysis of Transverse Unevenness with Respect to Traffic Safety
Authors: Kamplade J
Published: March 2009

SAQ, a device to measure and evaluate transverse unevenness due to ruts in asphalt roadways, is described. This is a mobile system used to record horizon referenced transverse profiles in a drive/stop process. It includes a microcomputer for processing all relevant parameters on board the measurement vehicle. Methods of the automated profile analysis are discussed, and different characteristic values for the evaluation of transverse unevenness are proposed.

Tracking and hydroplaning effects are caused by ruts which may affect traffic safety. In wet weather, skid resistance and the effects of transition zones (areas where the transverse slope changes) also have an influence on the accident figures in conjunction with the rutting problem. These parameters were investigated on a large number of autobahn segments. The results show that on roadways with mean and good skid resistance, accident rates under wet conditions tend to decrease as the rut or water depth increases. Only in transition zones, which feature unexpected obstructions to water run-off for the driver, is there an increase in the accident rate under wet conditions with increasing hypothetical water depth in the ruts. In addition, the accident risk in transition zones under wet conditions is also generally higher. The skid resistance always has a dominant effect on the accident rate under wet conditions. For road-maintenance measures, skid resistance therefore must be accorded clear priority over transverse unevenness.
Use of the Inertial Profilometer to Calibrate the Commonwealth of Kentucky Department of Highways' Mays Ride Meter Systems
Authors: Spangler EB , Rizenbergs RL , Burchett JL , Robinson DC
Published: March 2009

In May 1987, a project was undertaken in Kentucky to calibrate five Kentucky Department of Highways vehicle-mounted Mays Ride Meter (MRM) systems. An inertial profilometer operated by the National Bureau of Standards was used. Multiple elevation profiles were taken in order to evaluate the precision of the measuring method. Mean MRM Index values were computed for each MRM system. A second profilometer was used to determine that equivalent calibrations can be expected from identical inertial profilometers. A method was devised by which real measurements by individual MRM systems can be converted into Standard MRM Index values. Additional research is needed to determine the time stability of both the MRM systems and the pavement sections used in calibration.
Theoretical Principles, Methods, and Equipment for Pavement-Condition Measurements Specific for Road Management Systems
Authors: Procházka M , Kropáč O , Šprinc J , Lehovec F
Published: March 2009

Present developments in the field of pavement-management systems are primarily concerned with seeking relations between users' costs and variable pavement parameters. In this respect, the description and assessment of pavement-surface characteristics with regard to vehicle-pavement interaction and its stochastic character are of extreme importance. Only such an approach makes it possible to obtain both justified criteria and sought limit values for the models describing their development during pavement performance under traffic loads and the effect of climatic factors.

The marked stochastic character is inherent not only in surface characteristics as such, but also in the response of the vehicle and measurement equipment during their travels along the pavement. Therefore, theoretical foundations are presented along with assessment methods, response-type measuring devices, and routine methods used in the measurements of surface characteristics of highway and airfield pavements based on the theory of random functions, which have been introduced in Czechoslovakia.

The ascertained relations of pavement-surface characteristics are expressed most frequently by means of power spectral densities. Numerous results of in-site measurements, particularly by the mass-scale data collection in the highway network, may be processed in such a way that simple analytical functions or numerical constants may be deduced. However, the solution is always based on random-process theory and respects the vehicle-pavement interaction.

This simplified approach also forms the basis of the classification of vehicle response by means of the variance of vertical acceleration and, in a derived manner, also the classification of pavement unevenness by means of a logically introduced unevenness index.

The selected probabilistic approach based on vehicle dynamics also causes certain difficulties and limitations, for example, in the identification of the pavement-surface megatexture band (wavelengths from 0.5 up to 100 m) or in the solution of the influence of the respective unevenness band on skid resistance, which concerns tire-pavement interaction.

In spite of these problems, the stochastic concept of the solution of the problems of pavement-surface characteristics can be considered an efficient instrument which can considerably accelerate the finding of the sought relations between the technical and economic parameters in the design of the structure and quantification of the couples in full management systems.
Influence of Road Surface Roughness on Tire Noise Generation in the Federal Republic of Germany
Authors: Huschek S
Published: March 2009

The surface properties of a road pavement must fulfill a long list of requirements. Recently, this list has been extended to include acoustic properties. Since 1986, test stretches have been layed in the Federal Republic of Germany, with the goal of exploring noise-reducing wearing courses. Two methods are being used to evaluate tire noise, namely, the measurement of the noise immissions (that is, the noise propagated) with a fixed microphone and the noise emissions (that is, the noise sources) with a moving microphone in the near field of the tire. Experience shows that a high void content as well as a fine-grained surface is acoustically desirable. By employing appropriate drainage asphalt, the equivalent A-weighted sound level (Leq) can be reduced by 3 to 5 dB(A) in comparison with an asphalt concrete 0/11.
Splash and Spray
Authors: Pilkington GB
Published: March 2009

Like low pavement skid resistance, the aerodynamic phenomena of splash and spray are evident only when the pavement is wet. However, unlike low pavement skid resistance, splash and spray are separable and uniquely identifiable: (1) Splash is the mechanical action of a vehicle's tire forcing water out of its path. Splash is generally defined as water drops greater than 1.0 mm (0.04 in.) in diameter which follow a ballistic path away from the tire. (2) Spray is formed when water droplets, generally less than 0.5 mm (0.02 in.) in diameter and suspended in the air, are formed after water has impacted a smooth surface and been atomized. Several factors must be present: (a) water in the tire path (the thicker the water film, the greater the quantity of splash and spray generated); (b) pavement surface characteristics (thicker water films are retained on a nonporous surface); and (c) turbulent and high-velocity air masses generated by the combination of vehicle configuration and speed.

The Federal Highway Administration (FHWA) splash and spray research included driver simulator and wind-tunnel experiments, full-scale component, vehicle configuration, and countermeasure evaluations on test tracks, and cost-effectiveness analyses. The main findings were sixfold: 1. The driver simulator—A driver would not lose control of the vehicle due to the temporary visual obscurity due to the spray cloud, the turbulent air mass suspending the water droplets. 2. The wind tunnel—The areas were found where the spray cloud would be the densest, that is, the vehicle bow wave, around the wheels, and at gaps. 3. The full-scale component evaluations—Splash is water thrown away from the tire to the front (tire bow wave), to the side (side wave), and to the rear (tread pickup). Spray is water that the tire has picked up due to capillary adhesion and is stripped from the tire as it rotates and is atomized as it impacts the vehicle undercarriage. The splash from the tire that impacts the vehicle undercarriage will also be atomized and contribute to the spray cloud; however, only tread pickup is a major contributor to the cloud. 4. The full-scale configuration evaluations—these confirmed the wind tunnel findings. 5. The full-scale countermeasure evaluations—Spray can be effectively reduced by on-board countermeasures, such as baffles, dams, and drag shields, which reduce the size of the turbulent air mass. 6. The cost—effectiveness analyses-The most appropriate on-board countermeasures are cost effective on both regional and annual bases.

However, like improvement of skid resistance, the most effective and global countermeasures to reduce splash and spray are those applied at the pavement surface to reduce the amount of water in the tire path.
Monitor Well Drilling and Testing in Urban Environments
Authors: Smith SA
Published: March 2009

Experiences at Superfund sites in the metropolitan area of Phoenix, Arizona, have shown that installing and testing monitor wells in urban environments present special problems for the hydrogeologist and the well driller. Access is difficult to obtain, and noise, dust, water, and mud must be carefully controlled. Underground utilities must be accurately located prior to drilling, and overhead power lines are safety hazards to drilling rigs and pump rigs. Disposal of drilling fluids and cuttings, site cleanup, and well termination require special attention. Special permits or agreements may be required for drilling in urban areas; these include a permit to work in the public right-of-way, agreements with private land owners, a permit to discharge water from aquifer testing into the sewer system or surface waters, and a permit to obtain drilling water from fire hydrants. Traffic control barricades, police, and private security guards may be necessary to protect public safety. Some drilling methods are not practical in urban areas, and others may have to be modified. In comparison with rural areas, drilling and testing programs in urban areas require significantly more advance planning and are more costly.
Rationale for the Design of Monitoring Well Screens and Filter Packs
Authors: Schalla R , Walters WH
Published: March 2009

Well screens and filter packs are used extensively in the water well industry. Water supply wells are designed with large diameters to accommodate high-capacity pumps for municipal, industrial, and irrigation uses. Monitoring wells serve a different purpose, and therefore have some different design requirements. Monitoring wells are used to collect ground-water samples for chemical evaluation and are typically smaller in diameter and have shorter screened intervals. Monitoring well design, particularly for well screens and filter packs, must meet specific requirements. Unlike water wells, monitoring wells usually have an artificial filter pack between the formation and the well screen and often a secondary filter above the filter pack. The designs of well screens and filter packs are more critical for monitoring wells than for water wells, because monitoring wells serve as sampling ports in an aquifer and must minimize disturbance of the water chemistry and hydrology. At present, screen and filter pack requirements for monitoring wells have been only partially addressed by the technical community. Specific technical requirements should include filter pack parameters (i.e., uniformity coefficient, effective size, kurtosis, skewness, roundness, sphericity, and mineralogy). The method of filter pack placement, which involves particle settling through borehole fluids, is also important, particularly in relation to the nature of the geologic materials, the slot type and size of the screen, and the water level in the well.
Monitoring Well Rehabilitation Using the Surge Block Technique
Authors: Sevee JE , Maker PM
Published: March 2009

Monitoring wells at a site where the ground water is contaminated with organic solvents were rehabilitated using the surge block method. Several different methods were reviewed for their ability to remove sediments from the well as well as from the soils adjacent to the outside of the well screen. The surge block technique was selected as a method that would accomplish both objectives. The surge block technique is described and is compared with other well rehabilitaton methods. The results of presurging and postsurging groundwater quality from selected monitoring wells are presented. The surge block method was shown to increase the hydraulic capacity of the wells and removed sediment from the bottoms of the wells. Continued monitoring of the wells will indicate whether these benefits are short term or are related to accumulations of sediments at the bottoms of the wells.
Hydraulic Conductivity Determinations in Unlithified Glacial and Fluvial Materials
Authors: Bradbury KR , Muldoon MA
Published: March 2009

Experiences with many measurements of the hydraulic conductivity of unlithified glacial and fluvial materials in Wisconsin suggest that hydraulic conductivity must be viewed in terms of the operational scale of measurement, based on the scale of the problem at hand and the volume of the materials of interest. Frequently, the hydraulic conductivity of a given lithostratigraphic unit appears to increase as the operational scale of measurement increases. In particular, laboratory methods can yield hydraulic conductivities one to two orders of magnitude lower than conductivities determined in field tests on the same materials. The operational scale of most laboratory methods is much smaller than the operational scale of most field problems, and laboratory tests, although often logistically and financially attractive, may be of little value in characterizing the hydraulic conductivity of Pleistocene and recent deposits at working field scales.
In Situ Analysis of Benzene, Ethylbenzene, Toluene, and Xylenes (BTEX) Using Fiber Optics
Authors: Chudyk W , Pohlig K , Exarhoulakos K , Holsinger J , Rico N
Published: March 2009

In Situ Analysis of Benzene, Ethylbenzene, Toluene, and Xylenes (BTEX) Using Fiber Optics In situ analysis of ground water is an attractive alternative to conventional sampling and analysis methods, since it eliminates sample handling and chain-of-custody concerns. The prototype instrument recently developed by our research team uses remote laser-induced fluorescence (RLIF) to measure aromatic organics in situ. The work discussed here concerns the aromatic organics fraction of gasoline (benzene, toluene, and xylenes). RLIF can theoretically detect over half of the organics on the U.S. Environmental Protection Agency's Priority Pollutants List.

Typical analysis for these contaminants involves routine repetitive analysis, such as quarterly gas chromatography/mass spectroscopy (GC/MS) on samples taken from wells. Such monitoring is labor intensive, requiring a sampling team as well as a laboratory. Samples for GC/MS often take many weeks for analysis, so that remedial action information is late in arriving. An analysis is needed that is quick, simple, and less costly, providing a look at the situation as it currently exists.

The authors propose that routine GC/MS monitoring at characterized sites be replaced with RLIF measurements, supplemented with annual GC/MS analysis as a means of validation. Since RLIF analysis is nonspecific, this approach would be sound only at sites containing known aromatics as the contaminants of interest, or at sites where the aromatics concentration correlates with other problem compounds. Comparisons of RLIF and GC sensitivity for aromatic organics are discussed, with emphasis on the relative advantages and limitations of each method.
Special Problems of Ground-Water Monitoring in Karst Terranes
Authors: Quinlan JF
Published: March 2009

Reliable monitoring of ground-water quality in any terrane is difficult. There are many ways in which violation of sound principles of monitoring-network design and good sampling protocol makes it easy to acquire data that are not representative of the water or pollutants within an aquifer. In karst terranes it is especially easy for irrelevant data, which inadvertently misrepresent conditions within the aquifer, to be obtained.

The special problems of monitoring ground water in most karst terranes can be grouped into four major categories of problems that are rarely as significant in other terranes. These categories are the following: 1. Where to monitor for pollutants: The only relevant locations are at springs, cave streams, and wells that have been shown by tracing tests to include drainage from the facility to be monitored—rather than at wells to which traces have not been run but which were selected because of their convenient downgradient locations. Wells located on fracture traces and fracture-trace intersections and wells located randomly can be successfully used for monitoring, but only if there is a positive trace from the facility to them. Often successful monitoring can only be done several kilometres away from the facility. 2. Where to monitor for background: The only relevant locations are at springs, cave streams, and wells in fractured rock—in which the waters are geochemically similar to those to be monitored for pollutants but which have been shown by tracing tests not to drain from the facility—rather than at wells selected because of their convenient locations upgradient from the facility site. This, too, may have to be done several kilometres away from the facility. 3. When to monitor: Before, during, and after storms or meltwater events—rather than regularly with weekly, monthly, quarterly, semiannual, or annual frequency. 4. How to determine reliably and economically the answers to Problems 1, 2, and 3: Reliable monitoring of ground water in karst terranes can be done, but it is not cheap or easy.

These problems exist because many of the assumptions made for monitoring flow in granular media are not valid for karst terranes. Implicit assumptions made for monitoring in karst terranes with the strategy recommended herein can be stated axiomatically, but they are valid only about 95% of the time.

The monitoring strategy recommended herein is not applicable universally, but it is applicable in most karst aquifers, especially, all those that drain to springs. It is not applicable in terranes that are merely recharge areas of regional aquifers.
Analysis of Optical Measurements of Free-Surface Effects on Natural Surface and Through Cracks
Authors: Smith CW , Rezvani M , Chang CW
Published: March 2009

After briefly reviewing the algorithms used to convert experimental data into fracture parameters, experimental results are presented from experimental studies conducted on both compact bending specimens containing mutually grown “thumbnailed” cracks through the thickness and naturally grown surface flaws in wide plates. Results are compared with analytical results and are used to explain certain phenomena observed with both thumb-nailing of cracks in compact bending specimen and in the analyzing of surface flaws.
Measurements of CTOD and CTOA Around Surface-Crack Perimeters and Relationships Between Elastic and Elastic-Plastic CTOD Values
Authors: Reuter WG , Lloyd WR
Published: March 2009

A difficulty associated with predicting structural integrity is that the surface cracks found in structural components are three-dimensional whereas the crack-tip opening displacement (CTOD) and J-integral analytical techniques were derived from two-dimensional theory. This paper provides data from specimens containing surface cracks (aspect ratio either 0.1 or 0.5 and crack depth-to-thickness ratio 0.6); presents measured values of CTOD, crack-tip opening angle (CTOA), and Δa; provides experimental results relative to the center of rotation and the use of the Newman-Raju solutions for predicting the variation in CTOD around the crack perimeter; and evaluates possible correlations between CTOD, CTOA, and Δa.
Experimental Evaluation of Stress-Intensity Solutions for Surface Flaw Growth in Plates
Authors: Carter DK , Canda WR , Blind JA
Published: March 2009

This combined experimental and analytical study was directed at determining the growth and shape change of surface flaws under axial loading as compared with crack growth data obtained from simple compact tension specimens. The experimental effort aimed at measuring surface flaw crack growth rates for 2219-T851 aluminum specimens. Tests were conducted using constant-amplitude loading with marker bands to measure crack front shape changes.

The analytical effort evaluated available crack growth models and stress-intensity solutions and their ability to predict the growth and shape change of surface flaws. The characterization of surface flaws as semiellipses and the independence of crack growth rate and direction were addressed. The resulting model was successful in predicting growth and shape changes under most conditions. However, due to the variation between surface and depth crack growth rates for surface flaws, it was determined that crack growth data from compact tension specimens could not generally be used to characterize the growth of surface flaws.
Theoretical and Experimental Analyses of Surface Fatigue Cracks in Weldments
Authors: Niu X , Glinka G
Published: March 2009

The stress-intensity factor for a semi-elliptical surface crack in T-butt welded joints has been studied by using the weight function approach. The weight functions for cracks in welded joints have been derived by employing the method proposed by Petroski-Achenbach. The calculated stress-intensity factors were compared with those obtained from the variable-amplitude fatigue tests conducted on a series of T-butt welded joints. It has been shown that the weight functions provided sufficiently accurate solutions, in terms of the agreement between the calculated and measured stress-intensity factors and fatigue crack propagation lives. The method proved to be useful in studying weld plate thickness and weld geometry effects on fatigue crack growth in welded joints.
Methylene Blue Testing of Smectite as Related to Concrete Failure
Authors: Higgs NB
Published: March 2009

The navigation lock of Lower Monumental Dam, Washington required 1.2 million dollars 1n repairs as the concrete 1n the walls showed severe scaling because of lack of air entrainment and the presence of smectite (montmorillonite) in the Mabels Pit fine aggregate. Smectite because of its adsorptive-absorptive nature robs the mixture of water thus causing slump loss. It also increases drying-shrinkage volume changes.

Methylene blue staining of grain thin sections was used for quantifying the smectite 1n the Mabels Pit sand. The smectite turns blue with the staining, whereas muscovite nor biotite and most of the rock forming minerals do not stain. Utilizing this procedure indicated the No. 50 – No. 100 sieve size at Mabels Pit contains 23.8 percent smectite.

The methylene blue adsorption (MBA) is a titration process whereby the grains of a sieve fraction of a sand are ground to pass a No. 200 sieve and 2 grams of the powder is tested with methylene blue dye and a spot tested on filter paper until a light blue ring forms around the central dark blue spot. MBA values of greater than 2.5 m1/2 grams are associated with unsound concrete sands. The sieve size with 23.8 percent of smectite has an MBA value of 3.5.
Alkali-Aggregate Reaction Investigations at Friant Dam, California
Authors: Hartwell JN
Published: March 2009

Mass concrete at Friant Dam was produced with high- and low-alkali cements both with and without natural pozzolan (pumicite). Recent and previous investigations indicate (a) concrete deterioration due to alkali-aggregate reaction has taken place to varying extent and degree within the dam; (b) compressive strength and modulus of elasticity have decreased due to alkali-aggregate reaction; (c) preliminary tests suggest alkalies are not present in the concrete in sufficient quantity to contribute to expansive reactions; and (d) the potentially deleteriously alkali-reactive aggregate is of andesite affinity.
Opal-Coated Aggregates – Investigation and Processing for USE
Authors: Van Epps RJ , Erlin B
Published: March 2009

Petrographic examinations of gravel aggregate for use in the reconstruction of a dam revealed the presence of opal in coatings on aggregate particles. It was considered likely that the aggregate crushing and classifying operations would reduce most of the coatings. However, the removed opal needed tracking to insure that it was not in the fine aggregate.

Petrographic examinations were used to check the processed aggregate for opal. ASTM C227 tests, modified for use of the as-graded aggregate, was utilized to provide information on the potential for concrete expansion.

The data indicated that concrete made with cements having alkali contents of 0.36, 0.55, and 0.92 percent did not have expansions considered deleterious.

Because of the availability of low-alkali cement, the concrete was made using a cement having an alkali content of 0.4 percent. After over five years of service, the dam concrete does not contain outward evidence of alkali-silica aggregate reactions.