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  • Books  (488)
  • Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
  • Uppsala
  • Wuppertal : Wuppertal Institut für Klima, Umwelt, Energie
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  • 1
    Call number: ZSP-201-85/16
    In: CRREL Report, 85-16
    Description / Table of Contents: This report presents the results of the second phase of a test program designed to obtain a comprehensive understanding of the mechanical properties of multi-year sea ice from the Alaskan Beaufort Sea. In Phase 2, 62 constant-strain-rate uniaxial compression tests were performed on horizontal and vertical ice samples from multi-year pressure ridges to examine the effect of sample orientation on ice strength. Also conducted were 36 constant-strain-rate tension tests, 55 conventional triaxial tests and 35 constant-load compression tests on multi-year pressure ridge samples to provide data for developing ice yield criteria and constitutive laws. Data are presented on the strength, failure strain and modulus of multi-year sea ice under different loading conditions. The effects of ice temperature, porosity, structure, strain rate, confining pressure and sample orientation on the mechanical properties of multi-year sea ice are examined.
    Type of Medium: Series available for loan
    Pages: vi, 89 Seiten , Illustrationen
    Series Statement: CRREL Report 85-16
    Language: English
    Note: CONTENTS Abstract Preface Introduction Field sampling program Site selection and description Coring procedures Core logging procedures Shipping and storage of ice samples Ice description Salinity and density Structure Constant-strain-rate compression tests Test variables Uniaxial compressive strength Strength and structure Strength and porosity Residual compressive strength Failure strain Initial tangent modulus Constant-strain-rate uniaxial tension tests Test variables Uniaxial tensile strength Failure strains Initial tangent modulus Constant-strain-rate triaxial tests Equipment Test variables Synthane end caps Triaxial strength Failure strains Initial tangent modulus Effect of sinthane end caps on results Constant-load compression tests Test variables Test results Conclusions Literature cited Appendix A: Ice structure profile of ridge C core Appendix H: Test data Appendix C: Static determination of Young's modulus in sea ice
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  • 2
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    Call number: ZSP-201-85/17
    In: CRREL Report, 85-17
    Description / Table of Contents: This report presents the results of tests of the ice friction coefficient carried out during the May 1984 expedition of the F.S. Polarstern off the coast of Labrador. The test surfaces were Inerta-160-coated steel plates and bare steel plates, hand roughened and sandblasted. The main findings of the studies were: 1) columnar and granularpea ice showed no significant differences in friction coefficient; 2) for columnar ice was independent of ice crystal orientation with respect to test surface; 3) was Independent of normal pressure applied on ice sample; 4) initially decreased with increasing relative velocity between the Ice sample and the test surface and reached a steady value at higher speeds; 5) Uk increased with increasing surface roughness; 6) a wetting surface exhibited a higher friction coefficient than a non-wetting surface of the same or even higher roughness average.
    Type of Medium: Series available for loan
    Pages: iv, 26 Seiten , Illustrationen
    Series Statement: CRREL Report 85-17
    Language: English
    Note: CONTENTS Abstract Preface Introduction Test procedure Test apparatus Test surfaces Ice samples Test program Results and discussion Effect of wear of ice sample Effect of normal pressure Effect of velocity, crystal orientation and surface conditions Results summary Comparison with laboratory study Recommendations on test apparatus Literature cited Appendix A : Test results
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  • 3
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    Call number: ZSP-201-85/18
    In: CRREL Report, 85-18
    Description / Table of Contents: Concern over the environmental fate of explosives has brought about the development of sensitive analytical methods for measuring them in groundwater. In turn this concern has been extended to validating the sampling procedures for groundwater. This report addresses the potential effects of residual drilling muds on the analysis for explosive contaminants (TNT, DNT, RDX, and HMX) in monitoring wells. The approach was to determine sorption isotherms for each contaminant. Sorption appeared to be independent of solids concentration. Linear isotherms were obtained for RDX and HMX over a range of analytic concentrations; therefore, a single constant can be used to estimate the amount sorbed when the solution concentration is known. Isotherms for TNT and DNT were not linear, however. Scatchard analysis suggested that the isotherms for these analytes could be resolved into two predominant components: a linear component above a certain sorbed quantity and a Langmuir-type component below this quantity. The experimental data were fitted by regression analysis using the appropriate model. The equations developed can be used to predict the sorbed fraction (analytical bias) for any combination of solids and analyte concentration. The amounts of bentonite found in some existing wells do not appear to be sufficient to cause significant bias in analyses for these explosive contaminants.
    Type of Medium: Series available for loan
    Pages: iv, 40 Seiten , Illustrationen
    Series Statement: CRREL Report 85-18
    Language: English
    Note: CONTENTS Abstract Preface Introduction Materials and methods Bentonite and water samples Sorbate solutions Sorption isotherms HPLC analysis Analyte standards Water solubilities Octanol-water partition coefficients Sorption isotherms Freundlich Langmuir BET Scatchard Gibbs Linear Polynomial Results and discussion TNT DNT RDX and HMX Effect of drilling muds on analysis SEM and EDXA analysis of bentonite wells Other studies Summary Literature cited Appendix A : Results for TNT Appendix B: Results for DNT Appendix C: Results for RDX Appendix D : Results for HMX Appendix E: Characteristics of Quik-Gel, Aqua-Gel and well water
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  • 4
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    Call number: ZSP-201-85/19
    In: CRREL Report, 85-19
    Description / Table of Contents: Ground-probing radar can be an effective tool for exploring the top 10 to 20 m of ground, especially in cold regions where the freezing of water decreases signal absorption. However, the large electrical variability of the surface, combined with the short wavelengths used, can often cause severe ground clutter that can mask a desired, deeper return. In this study a model facility was constructed consisting of a metallic reflector covered by sand. Troughs of saturated sand were emplaced at the surface to vary surface electrical properties and to act as a noise source to interfere with the bottom reflections. Antenna polarization and height, and signal stacking in both static (antennas stationary) and dynamic (antennas moving) modes were then investigated as methods for reducing the surface clutter. Polarization parallel to the profile direction (perpendicular to the troughs' axes) gave profiles superior to the perpendicular case because of the directional sensitivity of the antenna radiation. Dynamic stacking greatly improved the signal-to-noise ratio because noise sources were averaged as the antennas moved, while the desired reflector, buried at constant depth, was enhanced. Raising the antennas above the surface also reduced noise because the surface area over which reflections were integrated increased. All three noise reduction techniques could be effective in surveys for reflectors at nearly constant depth such as groundwater tables or ice/water interfaces if the lateral variation in undesired ground propertiesis sufficiently random.
    Type of Medium: Series available for loan
    Pages: iv, 23 Seiten , Illustrationen
    Series Statement: CRREL Report 85-19
    Language: English
    Note: CONTENTS Abstract Preface Introduction Objective and procedures Materials and methods Subsurface radar Model facility Results Isolated disturbances-surface and raised analog profiles Multiple disturbances Discussion and conclusions Literature cited
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  • 5
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    Call number: ZSP-202-78
    In: Research report / Cold Regions Research and Engineering Laboratory, 78
    Description / Table of Contents: Summary: This climatological study makes use of the temperature, wind, and precipitation records from 12 stations on the Greenland Ice Sheet. Many of these stations were not in operation for concurrent periods and records for a year or more were available from only a few of them. The mean, mean maximum, mean minimum, absolute maximum, and absolute minimum temperatures were computed from the records. The highest absolute maximum temperature reported was 44°F at Mint Julep in southwestern Greenland. The lowest absolute minimum was -94°F at Northice in northern Greenland. This study shows that the prevailing wind usually was from the direction of the high central area of the ice sheet. Stations on the west slope had prevailing winds with an easterly component whereas stations on the east slope had prevailing winds with a westerly component. The wind speed varied from 0 to approximately 60 kt, but was predominantly in the 0 to 20 kt range. At some of the stations on the ice sheet, precipitation was measured in precipitation gages, at others it was measured as surface accumulation. At many locations the annual accumulation was determined from stratigraphic studies of the snow profile. The number of days on which snow occurred, expressed as percent of total days of observation, was used as an index to the amount of snowfall. The mean annual accumulation shows precipitation to be heavier on the west slope of the ice sheet than in other areas. The precipitation records at Northice indicate that the annual precipitation in that part of northern Greenland may be very light. The means for the various climatological parameters covered in this study are presented in tables and on a climatological map which presents a cartographic picture of the overall climatology of the Greenland Ice Sheet.
    Type of Medium: Series available for loan
    Pages: iv, 13, A5, B4 Seiten , Illustrationen
    Series Statement: Research report / Cold Regions Research and Engineering Laboratory 78
    Language: English
    Note: CONTENTS Preface Summary Introduction Air temperature Wind direction and speed Precipitation and accumulation Climatological map for the Greenland Ice Sheet Appendix A: Temperature data Appendix B: Precipitation data
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  • 6
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    Call number: ZSP-202-80
    In: Research report / Cold Regions Research and Engineering Laboratory, 80
    Description / Table of Contents: From the Introduction: During the last few years, there has been an increased interest in developing a rational explanation for the rather considerable variation in such bulk properties of sea ice as its strength, density, thermal conductivity, latent heat of melting, and coefficient of thermal expansion. Of these properties, sea-ice strength has received by far the most attention for practical reasons.
    Type of Medium: Series available for loan
    Pages: iv, 30, A6, B10, C2, D5 Seiten , Illustrationen
    Series Statement: Research report / Cold Regions Research and Engineering Laboratory 80
    Language: English
    Note: CONTENTS Preface Summary Introduction Experimentation Method of growing salt ice Strength test procedures Bulk properties of salt ice Phase relations Density and air content Strength results Strength of fresh-water ice Strength of NaCl ice as a function of brine volume Strength of NaCl· 2H2O ice as a function of the relative volume of solid salt Effect of thermal history on salt-ice strength Phase hysteresis Geometric hysteresis Effect of short-term cooling on the strength of fresh-water and NaCl·2H2O ice Effect of the volume of inclosed air on the strength of salt ice Conclusions NaCl ice Sea ice References Appendix A: Volume of brine and NaCl· 2H2O in NaCl ice as a function of salinity and temperature Appendix B: Ring test results Normal test sequences Appendix C: Ring test results Hysteresis test sequences Appendix .b: Ring test results Thermal history test sequences
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  • 7
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    Call number: ZSP-201-76/26
    In: CRREL Report, 76-26
    Description / Table of Contents: Debris over a 44-mile stretch of the Chena River was studied. The study area extended from the first bridge on the Chena Hot Springs Road to the Chena River Flood Control damsite. The purpose of the study was to assess the potential danger to the Chena River Flood Control Dam outlet structure. Debris was catalogued, log jams were measured, and sources of debris were studied. The average size of logs was determined, as well as the number of logs present on the river. The authors concluded that a serious debris problem existed and would remain serious for the foreseeable future. Recommendations for debris handling were made.
    Type of Medium: Series available for loan
    Pages: iv, 17 Seiten , Illustrationen
    Series Statement: CRREL Report 76-26
    Language: English
    Note: Contents Abstract Preface Summary Introduction Origin of debris Volume, magnitude Types of debris Hazards of the debris Recommended measures to counteract log jamming Conclusions and recommendations Future work Epilogue Selected bibliography Appendix: Additional photographs of Chena River debris
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  • 8
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    Call number: ZSP-201-76/25
    In: CRREL Report, 76-25
    Description / Table of Contents: The primary objective of this investigation was to compile baseline information pertaining to the ocean circulation, especially the extent and patterns of tidal currents and tidal flushing, in Cook Inlet, Alaska, utilizing aircraft and satellite imagery with corroborative ground truth data. LANDSAT-1 and NOAA-2 and -3 imagery provided repetitive, synoptic views of surface currents, water mass migration and sediment distribution during different seasons and tides. Color, color infrared and thermal infrared imagery acquired on 22 July 1972 with the NASA NP-3A aircraft were used to analyze currents, mixing patterns and sediment dispersion in selected areas. Temperature(C), salinity (0/00) and suspended sediment concentration (mg/l) data and hand-held photography were utilized as ground truth information in the interpretation of the aircraft and satellite imagery. Coriolis effect, semidiurnal tides and the Alaska current govern the estuary circulation. Clear, oceanic water enters the inlet on the southeast during flood tide, progresses northward along the east shore with minor lateral mixing, and remains a distinct water mass to the latitude of Kasilof-Ninilchik. South of the forelands, mixing with turbid inlet water becomes extensive. Turbid water moves south primarily along the north shore during ebb tide and a shear zone between the two water masses forms in mid-inlet south of Kalgin Island. Currents adjacent to and north of the forelands are complicated by tidal action, coastal configuration and bottom effects. Turbulence is greatest throughout the water column along the south shore and stratification is more pronounced in Kamishak and Kachemak Bays, especially when fresh water runoff is high.
    Type of Medium: Series available for loan
    Pages: ix, 92 Seiten , Illustrationen
    Series Statement: CRREL Report 76-25
    Language: English
    Note: CONTENTS Abstract Preface Summary Conversion factors: U.S. customary to metric (SI) units of measurement. Introduction Background Objectives Project history Approach Aircraft imagery LANDSAT-1 imagery NOAA-2 and -3 satellite imagery Ground truth data Imagery and ground truth data analysis Physical and cultural setting Geography Geology Climate Hydrology Local industry and population density Sources of estuarine pollution Results and discussion Coastal configuration Bathymetry Tides Asymmetry of tidal flow/duration across inlet Suspended sediment distribution and circulation Sea ice Tidal flushing characteristics Summary and conclusions Applications Recommendations Literature cited Appendix A. RS-14 infrared scanner imagery
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  • 9
    Call number: ZSP-201-76/30
    In: CRREL Report, 76-30
    Description / Table of Contents: The focus of this investigation was to assess the utility of remote sensing techniques in the study of land use-water quality relationships in an east central Wisconsin test area. The following types of aerial imagery were evaluated for this purpose: high altitude (60,000 ft) color, color infrared, multispectral black and white, and thermal; low altitude (less than 5000 ft) color infrared, multispectral black and white, thermal, and passive microwave. A non-imaging hand-held four-band radiometer was evaluated for utility in providing data on suspended sediment concentrations. Land use analysis includes the development of mapping and quantification methods to obtain baseline data for comparison to water quality variables. Suspended sediment loads in streams, determined from water samples, were related to land use of dfferences and soil types in three major watersheds. A multiple correlation coefficient R of 0.85 was obtained for the relationship between the 0.6-.7 incident and reflected radiation data from the hand-held radiometer and concurrent ground measurements of suspended solids in streams. Applications of the methods and baseline data developed in this investigation include: mapping and quantification of land use; input to watershed runoff models,estimation of effects of land use changes on stream sedimentation; and remote sensing of suspended sediment content of streams. High altitude color infrared imagery was found to be the most acceptable remote sensing technique forthe mapping and measurement of land use types.
    Type of Medium: Series available for loan
    Pages: vi, 53 Seiten , Illustrationen
    Series Statement: CRREL Report 76-30
    Language: English
    Note: CONTENTS Abstract Preface Conversion factors: U.S. customary to metric (SI) units of measurement lntroduction Objectives Approach and project history Study area Physical setting Cultural setting Documented pollution sources in the study area Evaluation of imagery Photographic imagery Thermal imagery PMIS imagery Land use analysis Analysis of 1972 imagery Analysis of 1974 imagery Soils of Manitowoc, East Twin and Oconto River watersheds Manitowoc River watershed East Twin River watershed Oconto River watershed Water quality data Manitowoc River East Twin River Oconto River Land use/stream sedimentation relationships Results and conclusions Sensor evaluation Land use analysis Mapping approaches Land use/sedimentation relationships Cost effectiveness analysis Recommendations and applications Selected bibliography Appendix A. Precipitation and temperature data
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  • 10
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    Call number: ZSP-202-101
    In: Research report / Cold Regions Research and Engineering Laboratory, 101
    Description / Table of Contents: Partial Summary: This paper is a pilot study of interrelations between structural features readily observed in horizontal thin sections of sea ice under low magnification. The core studied was 31.4 cm in length and was collected from Elson Lagoon at Point Barrow, Alaska on 26 October 1960.
    Type of Medium: Series available for loan
    Pages: iv, 11 Seiten , Illustrationen
    Series Statement: Research report / Cold Regions Research and Engineering Laboratory 101
    Language: English
    Note: CONTENTS Preface Summary Introduction Petrographic characteristics Intercrystalline features Intracrystalline features References
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  • 11
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    Call number: ZSP-202-100
    In: Research report / Cold Regions Research and Engineering Laboratory, 100
    Description / Table of Contents: From the Summary: During the summer of 1960, observations were made of ground fog on the Greenland Ice Cap and of sea fog in the Thule area in northwestern Greenland. A microscope-stage-fog impactor was designed, and its collection efficiency determined both empirically and by computation from the theoretical work of Langmuir and Blodgett (1946). The empirical efficiency was found to be considerably greater than the theoretical efficiency.
    Type of Medium: Series available for loan
    Pages: iv, 13 Seiten , Illustrationen
    Series Statement: Research report / Cold Regions Research and Engineering Laboratory 100
    Language: English
    Note: CONTENTS Preface Summary Introduction Method Design and operation of the impactor Collection efficiency Computation from theoretical values of Langmuir and Blodgett Empirical values Observations and results Fog on the ice cap Sea fog near Thule Discussion Conclusions References
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  • 12
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    Call number: ZSP-202-106
    In: Research report / Cold Regions Research and Engineering Laboratory, 106
    Description / Table of Contents: From the Preface: This paper presents a method for determining the extent of heat transfer due to vapor transfer in snow with air flowing through it, which could be useful in connection with studies concerning the changes of physical and mechanical properties of a snow cover caused by temperature gradients and wind currents.
    Type of Medium: Series available for loan
    Pages: iv, 8, A2, B2, C4 Seiten , Illustrationen
    Series Statement: Research report / Cold Regions Research and Engineering Laboratory 106
    Language: English
    Note: CONTENTS Summary Introduction Theory Experimental apparatus apd procedures Results and discussion References Appendix A: Evaluation of d^2Ps/dx^2, dps/dx Appendix B: Sample calculations of β0, β, and De Appendix C: Experimental results and calculated data
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  • 13
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    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
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    Call number: ZSP-201-76/45
    In: CRREL Report, 76-45
    Description / Table of Contents: The maneuverability of air cushion vehicles can become a serious operational problem when the vehicle's travel route is restricted by obstacles, slopes or cross-wind conditions, or when close-quarter turns are required. While improvement and perfection of aerodynamic methods may be a more desirable approach, there is a practical limit to these methods, and the use of ground contact devices requires consideration for providing more positive directional control. Wheels deserve special attention, and therefore are analyzed in more detail because of their obvious application on a variety of land terrains. Brake rods and harrows are more suitable on water, ice and snow. The saucer-shaped ground contact device would cause the least ecological impact on fragile organic terrains such as tundra. Relative directional stability is evaluated in terms of the total yawing moments produced by wheel arrangements (single, dual, tandem), location on the vehicle, and operational modes (free-rolling, braked, or a combination of the two). The available moments are plotted against the yaw angle of the vehicle to determine the most effective operational mode with a particular wheel arrangement for any yaw condition. The analysis is limited to retractable devices which act as moment producing brakes or rollers and do not serve as either propulsion or load support aids. Controlled ground contract with skirt sections having special wearing surfaces may provide a suitable control method and would require the least significant change to the basic design of the vehicle or its components. The concept involves the use of an air flow control mechanism for deflating specific skirt sections.
    Type of Medium: Series available for loan
    Pages: vii, 15 Seiten , Illustrationen
    Series Statement: CRREL Report 76-45
    Language: English
    Note: CONTENTS Abstract Preface Nomenclature Conversion factors: U.S. customary to metric (SI) units of measurement Section I: Use of auxiliary devices for ACV control Introduction Discussion of wheels as a control device Dual wheels Single wheel Tandem wheels Application to existing ACV’s Other control devices Turning force Conclusions Section II: Use of flexible skirts for ACV control Introduction The flexible skirt as a control device Model tests Conclusions Literature cited
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  • 14
    Call number: ZSP-201-85/15
    In: CRREL Report, 85-15
    Description / Table of Contents: A method for the analysis of TNT, RDX and HMX explosives in soils and sediments has been developed. It consists of methanol extraction followed by reversed-phase high performance liquid chromatography using 10% acetonitrile/40% methanol/50% water as the eluant. This method was used to study the effect of various drying techniques upon the recovery of TNT, RDX, and HMX from soil and sediment samples contaminated with high (%) and low (micron g/g) levels of these explosives. For highly contaminated samples, complete recovery of TNT and RDX was obtained using freeze drying while air drying at room temperature resulted in greater than 90% recovery for both explosives. Other techniques, such as oven drying at 105 C, oven drying at 45 C, microwave oven drying, and drying under infrared lamps, all resulted in greater losses, with TNT and RDX recoveries ranging from 76 to 90%. Drying losses were not due to simple volatilization containing low levels of TNT, RDX and HMX, recoveries of all three explosives were quantitative for all the above drying techniques.
    Type of Medium: Series available for loan
    Pages: iii, 15 Seiten , Illustrationen
    Series Statement: CRREL Report 85-15
    Language: English
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  • 15
    Call number: ZSP-201-94/12
    In: CRREL Report, 94-12
    Description / Table of Contents: Subsurface radar was used to profile ice and snow conditions on the Ross Ice Shelf at McMurdo Station, Antarctica, during mid-January 1993. Deconvolution and migration were often used to improve vertical resolution and spatial imaging. Profiles at a pulse center frequency of 400 MHz along the 3.2-km-long Pegasus ice runway show many low-density horizons above 9 m depth that are up to 30 m long. They are associated with air bubbles included during refreezing of meltwater and are interpreted as layers between a few and tens of centimeters thick. There is a strong reflecting horizon at about 9 m depth that is probably from brine intrusion as it is continuous with the intrusion into the snow to the east. Diffraction asymptotes give a dielectric constant near 3.2 for material above the brine level, a value that implies near-solid ice. Profiles at 100 MHz along the road between Pegasus runway and Williams Field in the accumulation zone show snow features such as layer deformation and intrusive brine layers that both abruptly and gradually change in depth. A single profile at a relic solid waste dump at Williams Field detected buried debris and ice within the upper 7 m. A survey of a suspected fuel spill shows some local disturbances near the center, but no excavation was done to verify the findings. Profiles traversing the sewage sumps at Williams Field outline the extent of the sewage deposition, and give depths to contaminated snow that closely agree with observation. Despite variability in dielectric properties, single-layer migration effectively improves the resolution of subsurface conditions. Recommendations are made for future surveys.
    Type of Medium: Series available for loan
    Pages: iv, 29 Seiten , Illustrationen
    Series Statement: CRREL Report 94-12
    Language: English
    Note: CONTENTS Preface Introduction Radar equipment General operation Antennas Waveforms and phase polarity Antenna directivity Field procedures and data processing Field procedures Data recording Data processing Site location Results Pegasus runway Access road from Williams Field to Pegasus runway Williams Field Summary and conclusions Literature cited Appendix A: Airborne profile of a portion of the access road Abstract
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  • 16
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    Call number: ZSP-201-80/15
    In: CRREL Report, 80-15
    Description / Table of Contents: This report discusses the time constraints on measuring the thermal resistance (R-value) of building components. Temperature changes on either side of a building component perturb measurement accuracy. Long measurement times and measurement times corresponding to a consistent diurnal cycle can be satisfactory; however, individual temperature changes cause significant error for shorter measurement periods. This report shows how to scale the thermal properties of individual constituent materials in a building element to determine its characteristic thermal time constant. The report then demonstrates the size of measurement error resulting from a variety of changes in temperature with representative walls of different time constants.
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    Pages: iii, 30 Seiten , Illustrationen
    Series Statement: CRREL Report 80-15
    Language: English
    Note: CONTENTS Abstract Preface Conversion factors Introduction Field measurement and analysis of transient heat flow A closer look at handling the constraints Random change Step change Ramp change Application of theory Literature cited Appendix A. Percentage error from a step input Appendix B. Time constraints of sample walls Appendix C. Percentage error from a ramp input Appendix D. Percentage error from a sinusoidal input Appendix E. Percentage error programs for a Hewlett-Packard HP-25 calculator Appendix F. Experimental determination of time constants Appendix G. Derivation of time constant formula for multiple layers
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  • 17
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    Call number: ZSP-201-76/29
    In: CRREL Report, 76-29
    Description / Table of Contents: In order to verify current theoretical equations on ice bearing capacity, a heavily loaded truck was used to make successive passes over two ice bridges. Equipment, weather and the normal problems associated with field work resulted in only one complete breakthrough test. Breakthrough occurred on one bridge with a vehicle weight of 53,630 lb (24,327 kg) and an ice thickness of 17.5 in. (44.5 cm). Since only one test was completed, the conclusions drawn cannot be unequivocal. However, the results do indicate that Nevel's equation for ultimate failure of a floating ice sheet is a good working tool.
    Type of Medium: Series available for loan
    Pages: iv, 19 Seiten , Illustrationen
    Series Statement: CRREL Report 76-29
    Language: English
    Note: Contents Abstract Preface Summary Introduction Location Test procedure Loading Site preparation and bridge construction Deflection measurements Conclusions Literature cited Appendix, Test data
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  • 18
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    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
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    Call number: ZSP-201-82/16
    In: CRREL Report, 82-16
    Description / Table of Contents: Abstract: A dynamic-thermodynamic sea ice model which employs a viscous-plastic constitutive law has been applied to the East Greenland area. The model is run on a 40-km spatial scale at 1/4-day time steps for a 60-day period with forcing data beginning on 1 October 1979. Results tend to verify that the model predicts reasonable thicknesses and velocities within the ice margin. Thermodynamic ice growth produces excessive ice extent, however, probably due to inadequate parameterization of oceanic heat flux. Ice velocities near the free ice edge are also not well simulated, and preliminary investigations attribute this to an improper wind field in this area. A simulation which neglects ice strength, effectively damping ice interaction with itself and allowing no resistance to deformation, produces excessive ice drift toward the coast and results in unrealistic nearshore thicknesses. A dynamics-only simulation produced reasonable results, including a more realistic ice extent, but the need for proper thermodynamics is also apparent. Other simulations verify that ice import from the Arctic Basin, and ice transport due to winds and currents, were also important components in the model studies.
    Type of Medium: Series available for loan
    Pages: v, 40 Seiten , Illustrationen , 29 cm
    Series Statement: CRREL Report 82-16
    Language: English
    Note: CONTENTS Abstract Preface Introduction Model description and application Results and discussion Wind and current fields Standard simulation Thermodynamic simulation Zero ice strength Zero ice import Zero currents Modified currents Zero winds Dynamics simulation Summary and concluding remarks Literature cite
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  • 19
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    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
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    Call number: ZSP-202-105
    In: Research report / Cold Regions Research and Engineering Laboratory, 105
    Description / Table of Contents: Summary: A principle of particle segregation by freezing is presented. It is demonstrated experimentally by using a transparent freezing cabinet in which a sample of distilled water freezes from the bottom upward. In this way the freezing front line travels vertically and the particles are carried against gravity. By using the same material with different shapes (glass beads and broken quartz or glass) it is demonstrated that an important factor in particle migration is the shape of the particle or its contact area with the interface. By testing other materials with different shapes and sizes, it is demonstrated that another important factor is particle size and rate of freezing. Fine particles migrate under a wide range of rates of freezing; coarser ones migrate at lower and more limited ranges of rates of freezing. It is suggested that, for determining frost behavior of soils in permafrost regions, freezing from the bottom upward is a more reliable test than freezing from the top down. Freezing from the bottom more closely approximates freezing of the active layer above permafrost; also, friction with the cylinder testing wall is eliminated. The implication of this principle in engineering and studies of soil genesis in cold regions is emphasized.
    Type of Medium: Series available for loan
    Pages: iv, 8 Seiten , Illustrationen
    Series Statement: Research report / Cold Regions Research and Engineering Laboratory 105
    Language: English
    Note: CONTENTS Preface Summary Introduction Experimental procedure Experimental results Conclusions and recommendations References
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  • 20
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    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
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    Call number: ZSP-202-108
    In: Research report / Cold Regions Research and Engineering Laboratory, 108
    Description / Table of Contents: Summary: The theory of snow densification is further developed on the basis of an exponential relation between viscosity and density. A linear relation between load-stress and strain rate is not valid for high stresses, and is replaced by a hyperbolic sine function. An empirical function is given for the temperature cycle correction. Two equations are derived for calculating depth-density curves with computers, and a simplified one for use with desk calculators. Instructions are given for determination of function parameters from field data. Four depth-density curves for Greenland and Antarctic locations are computed and graphed to show that the theory is useful.
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    Pages: iv, 18, A3, B5 Seiten , Illustrationen
    Series Statement: Research report / Cold Regions Research and Engineering Laboratory 108
    Language: English
    Note: CONTENTS Preface Summary Introduction Notation Stress analysis Analysis of densification process Non-Newtonian densification Equation for hyperbolic sine densification law Determination of parameters Discussion Glaciological engineering aspects References Appendix A: Example of calculation Appendix B: Snow density profiles
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  • 21
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    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-77/1
    In: CRREL Report, 77-1
    Description / Table of Contents: Studies of the growth history and structural characteristics of winter ice covers on two New Hampshire lakes are described. These investigations included measurements of ice cover thickness, characterization of the stratigraphic and crystalline structure of the ice, identification and classification of major ice types and measurements of electrolytic conductivity. The formation of cracks and flaws in the ice and their effects on the mechanical properties of the ice were also investigated. A method of correlating ice growth with surface wind and temperature measurement is described and the interrelationships of the various physical and mechanical properties of temperate lake ice covers are discussed.
    Type of Medium: Series available for loan
    Pages: v, 29 Seiten , Illustrationen
    Series Statement: CRREL Report 77-1
    Language: English
    Note: CONTENTS Abstract Preface Summary Introduction Study areas Study methods Winter freeze-up Composition of ice cover Freezing degree day records and applications Evaluation of ice growth coefficient α Growth history and entrapped bubble stratigraphy Mechanical properties Electrolytic conductivity Literature cited
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  • 22
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    Call number: ZSP-201-77/2
    In: CRREL Report, 77-2
    Description / Table of Contents: A computer program was developed for finding the d-c resistance to ground of two simple electrodes, a straight horizontal wire and a vertically driven rod. The objective of this study was to develop a rapid means of finding the resistance to ground of simple electrode types in arctic environments where a two-layer earth model, frozen and unfrozen ground, is applicable. The program can consider homogeneous as well as two-layer earth, and the length, diameter and position of the electrodes. The computations were performed first by dividing an electrode into several smaller segments. Next the electrostatic potential of each segment was computed at the center of the electrode for unit-applied current. The segment potentials were then summed to find the total resistance to ground. Some specific computations are presented in comparison with previous theoretical work of other authors. The following conclusions were made: 1) A maximum run time of 165 seconds is needed for all two-layer arctic models where (a) the depth of the upper layer does not exceed 10 m, (b) the vertical rod length is less than 30 m, or (c) the horizontal wire length is less than 100 m; 2) Best accuracy is obtained when rod and wire radii are less than 0.01 m; and 3) Coincidence of the center of the vertical electrode with the two-layer interface must be avoided.
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    Pages: iv, 16 Seiten , Illustrationen
    Series Statement: CRREL Report 77-2
    Language: English
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  • 23
    Call number: ZSP-201-76/24
    In: CRREL Report, 76-24
    Description / Table of Contents: Chemical analysis of surface snows and deeper ice core samples from Milcent, Greenland, indicates a marine origin for Na and Cl and a terrestrial origin for Al, Mn and V. Pre-1900 enrichment factors, based on average crustal composition, are high for Zn and Hg and appear to be related to their volatility. A comparison of pre-1900 and 1971-1973 concentrations of V and Hg shows no decided increase from industrial production; however, the abundance of Zn (relative to Al) increased three-fold during this time period. The chemical composition of ancient ice is extremely useful in interpreting modern aerosols.
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    Pages: ii, 6 Seiten , Illustrationen
    Series Statement: CRREL Report 76-24
    Language: English
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  • 24
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    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
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    Call number: ZSP-201-80/25
    In: CRREL Report, 80-25
    Description / Table of Contents: Two new types of load cells for attachment to bridge piers and direct measurement of ice forces were developed and tested with one type being installed on a pier of the Yukon River Bridge northwest of Fairbanks, Alaska. Both types of load cells used beams supported by base plates and carried nose plates that were loaded by the ice. The loads were imposed at the beams at locations differing from the support reactions so that the loads developed moments in the beams. By instrumenting them with strain gauges, the loads could be measured. Details of the design of the load cells, the means of calculating the loads and experience obtained with load cells are discussed.
    Type of Medium: Series available for loan
    Pages: iii, 17 Seiten , Illustrationen
    Series Statement: CRREL Report 80-25
    Language: English
    Note: CONTENTS Preface Conversion factors Introduction Estimates and field measurements of ice forces on structures General Indirect estimates Direct measurements Small-scale and laboratory studies Instrumentation plan for measuring ice loads on the Yukon River Bridge Load cell development The single reaction beam system Performance of a single reaction beam load cell The double reation beam load cell Reaction beam design Stress in the beam Deflection Axial tensile stress in the reaction beam Measurement techniques Conclusions Literature cited Appendix A. Finding load magnitude and location with a single reaction beam device Appendix B. Finding load magnitude and location on a double reaction beam device
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    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-80/23
    In: CRREL Report, 80-23
    Description / Table of Contents: The contribution of brine layers to observed reflective anisotropy of sea ice at 100 MHz is quantitatively assessed. The sea ice is considered to be a stratified, inhomogeneous, anisotropic dielectric consisting of pure ice containing ordered arrays of conducting inclusions (brine layers). Below the transition zone, the ice is assumed to have constant azimuthal c-axis orientation within the horizontal plane, so that the orientation of brine layers is uniform. The brine layers are also assumed to become increasingly well-defined with depth, since adjacent brine inclusions tend to fuse together with increasing temperature. A theoretical explanation for observed reflective anisotropy is proposed in terms of an isotropic electric flux penetration into the brine layers. Penetration anisotropy and brine layer geometry are linked to anisotropy in the complex dielectric constant of sea ice. In order to illustrate the above effects we present a numerical method of approximating the reflected power of a plane wave pulse incident on a slab of sea ice. Mixture dielectric constants are calculated for two polarizations of the incident wave: 1) the electric field parallel to the c-axis direction, and 2) the electric field perpendicular to the c-axis direction. These dielectric constants are then used to calculate power reflection coefficients for the two polarizations. Significant bottom reflection (R ~ 0.08) occurs when the polariza-tion is parallel to the c-axis. However, when the polarization is perpendicular to the c-axis, the return may be almost completely extinguished (R 〈 0.001). This extinction is due primarily to absorptive loss associated with the conduct-ing inclusions and secondarily to an impedance match at the ice/water interface that results in transmission of the wave to the water without reflection.
    Type of Medium: Series available for loan
    Pages: vi, 15 Seiten , Illustrationen
    Series Statement: CRREL Report 80-23
    Language: English
    Note: CONTENTS Abstract Preface List of symbols Introduction Anisotropy and sea ice macrostructure Anisotropy and sea ice microstructure A theory of anisotropic radar return from sea ice Anisotropic electric flux penetration into brine layers Implications of normal exclusion, tangential penetration, and brine layer geometry for dielectric behavior of sea ice Modeling of electromagnetic reflection from a stratified, anisotropic, inhomogeneous lossy medium Calculation of mixture complex dielectric constants Calculation of interfacial power reflection coefficients Calculation of bulk power reflection coefficients Calculation of attenuated power reflection coefficients Beam spread Results Anisotropic bottom reflections Anisotropic complex dielectric constants Sensitivity of parameters Internal reflection: the bumps Discussion Conclusions Literature cited
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  • 26
    Call number: ZSP-201-80/19
    In: CRREL Report, 80-19
    Description / Table of Contents: During the period 1975-1978 the Federal Highway Administration sponsored a series of environmental engineering in­vestigations along the Yukon River to Prudhoe Bay Haul Road. In 1976 the Department of Energy joined these in­vestigations with a series of ecological projects which continue to the present. Both agencies research efforts were con­ducted on a cooperative basis with CRREL’s in-house research program. The objectives of the research focused on 1) an evaluation of the performance of the road, 2) an assessment of changes in the environment associated with the road, 3) documentation of flora and vegetation along the 577-km-long transect, 4) methodologies for revegetation and restoration, and 5) an assessment of biological parameters as indicators of environmental integrity. In support of these objectives, specific studies were undertaken that investigated the climate along the road, thaw and subsidence beneath and adjacent to the road, drainage and side slope performance, distribution and properties of road dust, vegetation distribution, vegetation disturbance and recovery, occurrence of weeds and weedy species, erosion and its control, revegetation and restoration, and construction of the fuel gas line. This report presents background, information on the region, detailed results of the road thaw subsidence and dust investigations, and summaries of revegetation, fuel gas line, vegetation distribution, soil, and weed studies.
    Type of Medium: Series available for loan
    Pages: xv, 187 Seiten , Illustrationen
    Series Statement: CRREL Report 80-19
    Language: English
    Note: CONTENTS Abstract Preface Summary Introduction Chapter 1. The road and its environment Introduction General physiography Regional climate Surficial and bedrock geology Permafrost and ground ice General biota Vegetation Floristic survey Vegetation mapping Soils and mapping Chapter 2. Roadbed performance and associated investigations Roadbed investigations Roadbed performance Performance of drainage features Performance of sideslopes Conclusions from road, drainage and sideslope performance studies Fuel gas line construction Chapter 3. Distribution and properties of road dust along the northern portion of the Haul Road Introduction Methods Results of wind direction and velocity measurements Dust load and distribution Particle size analyses of dust Chemical composition properties of dust and related samples Soil cation composition Dust impacts on vegetation Discussion and conclusions Chapter 4. Revegetation and restoration investigations Introduction Revegetation approaches Alyeska erosion control and revegetation program Weeds and weedy plants Performance of revegetation Alyeska willow cutting program CRREL restoration experiments Conclusions Revegetation recommendations General report recommendations Literature cited Appendix A: General environmental guidelines applicable to subarctic and arctic road construction Appendix B: University-based studies along the Yukon River-Prudhoe Bay Haul Road Appendix C: CRREL maps of Haul Road showing locations of all study Sites Appendix D: Additional Haul Road cross-sectional profiles Appendix E: Clay mineralogy of road-related materials Appendix F: List of reports in the Joint State/Federal Fish and Wildlife Ad­visory Team series
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  • 27
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    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-202-85,2
    In: Research report / Cold Regions Research and Engineering Laboratory, 85,2
    In: The frost behavior of soils : laboratory and field data for a new concept, Part II
    Description / Table of Contents: Laboratory experiments were performed with a specil closed-system side-freezing cabinet in which completely saturated soil samples were subjected to alternate freeze-thaw cycles without surcharge. A vertical or nearly vertical freezethaw plane was obtained in the side-freezing cabinet. The soil used was a straight graded noncohesive material with 14 finer than the No. 200 0.074 mm mesh sieve. According to frost criterion based only on gradation, the soil would be classified as a never frost-heaving moraine soil or non-frost-susceptible. All experiments were run for 20 and 22 cycles. Freezing rates used were as follows 30.0 mmhr 33.0 mmhr and 4 .0 mmhr. The initial dry density was approximately constant for each test at 1.8 gcm3 or 112.4 lbft3, and complete saturation was maintained in the tests.
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    Series Statement: Research report / Cold Regions Research and Engineering Laboratory 85,2
    Language: English
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    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-202-94
    In: Research report / Cold Regions Research and Engineering Laboratory, 94
    Description / Table of Contents: Summary: A new mechanism is described which explains the formation of moraines in the ablation areas of cold ice caps. The mechanism involves the freezing of water onto the bottom surface of an ice cap. This water comes from regions of the bottom surface where the combination of the geothermal heat and the heat produced by sliding of ice over the bed is sufficient to melt ice. A number of criticisms are made of the shear hypothesis, which has been advanced to explain moraines occurring on Baffin Island and near Thule, Greenland. It is concluded that this older hypothesis may be inadequate to account for these moraines. Although in theory the mechanism proposed here undoubtedly would lead to the formation of moraines, the existing field data are insufficient to prove conclusively that actual moraines have originated in this way.
    Type of Medium: Series available for loan
    Pages: iv, 12 Seiten , Illustrationen
    Series Statement: Research report / Cold Regions Research and Engineering Laboratory 94
    Language: English
    Note: CONTENTS Preface Summary Introduction Comments on the shear hypothesis Appearance of the debris layers The possibility of cold ice scraping up debris The shear across a debris layer The geometry of the debris layers Freezing model Theory Discussion Conclusion References
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    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-202-88
    In: Research report / Cold Regions Research and Engineering Laboratory, 88
    Description / Table of Contents: Summary: Four ground patterns were investigated by means of trenches cut in the outwash near Thule, Greenland: circular and linear depressions in unsorted material, polygonal troughs in unsorted material, sorted circles, and irregular mounds and depressions of low relief formed in unsorted finer grained material. Correlation is made between surface pattern, grain size and structure of the active layer, and type and distribution of ground ice for the patterns investigated. Classification of the active layer as disturbed, slightly disturbed, and undisturbed is based on the condition of primary depositional bedding and the presence or absence of vertical sorting. Other features of the active layer, depending upon its type, are an accumulation of fines at the bottom of the active layer and on top of stones, and a siliceous calcareous evaporite on the under surface and clean washed coarser particles beneath the larger stones. Fabric analysis of four kinds of ground ice is presented: ice wedge, relict ice, ice mass, and ice lens, as well as analysis of the contact of ice wedges with relict and mass ice. Practical applications, based on the conclusions, are given for the selection of foundation sites and the location of non-frost-susceptible building materials. NOTE: This is a very large file. Please give your browser several minutes to download the file.
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    Pages: viii, 79 Seiten , Illustrationen
    Series Statement: Research report / Cold Regions Research and Engineering Laboratory 88
    Language: English
    Note: CONTENTS Preface Summary Introduction Glossary Part 1 : Surface pattern, structure of the active layer, and type and distribution of ground ice in the permafrost Pattern type 1: Circular and linear depressions in unsorted outwash Circular depressions, area 1 Structure of the active layer Ground ice and its relation to surface morphology Linear depressions, area 5 Structure of the active layer Ground ice and its relation to surface morphology Pattern t ype 2 and 3: Polygonal troughs in unsorted outwash and sorted circles or centers of fines Area 3 Structure of the active layer Ground ice and its relation to surface morphology Area 4 Structure of the active layer Ground ice and its relat ion to surface morphology Pattern type 4: Mounds and depressions of low relief in unsorted outwash Area 4a Structure of the active layer Ground ice and its relatiop. to surface morphology Part 2: Ground ice studies Area 1 Lens ice History Appearance of the ice Fabric analysis Wedge ice History Appearance of the ice Fabric analysis Relict ice History Appearance of the ice Fabric analysis Contact between ice wedge and relict ice Ice sockets Area 5 Wedge ice Fabric analysis Relict ice Fabric analysis Area 3 Ice mass History Appearance of the ice Fabric analysis Ice wedge Fabric analysis Contact between ice mass and wedge Appearance of the ice Fabric analysis Summary and conclusions Pattern type 1: Linear and circular depressions in. unsorted outwash Pattern type 2: Polygonal troughs formed in unsorted outwash Pattern type 3: Sorted circles or centers of fines Pattern type 4: Mounds and depressions of low relief in fine-grained unsorted outwash Engineering applications References Appendix A: Associated studies Appendix B : Recommendations for further field and laboratory work Appendix C: Recommendations for field and laboratory techniques
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    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
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    Call number: ZSP-201-80/28
    In: CRREL Report, 80-28
    Description / Table of Contents: This report investigates the feasibility of clearing ice from the shipping channel of the St. Marys River. Four basic concepts are investigated: disposal under the ice, disposal on top of the ice, slurrying, and rafting. Each technique was found to have application in limited portions of the river with the exception of disposal on top of the adjacent ice sheet which is deemed feasible throughout the river system. Disposal onto the adjacent ice sheet will increase the free stream velocity less than 1.0 ft/s (30.5 cm/s) and raise the water level less than 1.0 ft (0.30 m). Further model and field tests are recommended to validate the findings of this report.
    Type of Medium: Series available for loan
    Pages: ii, 13 Seiten , Illustrationen
    Series Statement: CRREL Report 80-28
    Language: English
    Note: CONTENTS Abstract Preface Introduction The Environment Ice Growth and Accumulation Natural Ice Transport Accumulation Sites 1. Under-ice accumulation 2. Accumulation on top of the ice Evaluation of Ice Disposal Techniques 1. General 2. Disposal by displacement under the remaining ice sheet 3. Disposal by ejection on top of adjacent ice cover 4. Disposal by slurrying 5. Disposal by rafting Conclusions and Recommendations Literature Cited
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    Call number: ZSP-201-80/29
    In: CRREL Report, 80-29
    Description / Table of Contents: This study was conducted to determine the short- and long-term physical, chemical and biological effects of spills of hot Prudhoe Bay crude oil on permafrost terrain near Fairbanks, Alaska. Two experimental oil spills, one in winter and one in summer, of 7570 liters (2000 gallons) were made at a forest site. The winter-spill oil moved within the surface moss layer beneath the snow. The summer-spill oil moved primarily below the moss in the organic soil. The oil moved faster and further downslope in the summer spill. Oil in the winter spill stopped during the first day but remobilized and flowed further downslope in the spring. The total area affected by the summer spill was nearly one and one-half times as large as that affected by the winter spill. The initial heat of the spilled oil had little measurable thermal effect on the soil. However, thaw depth significantly increased following two full thaw seasons. The greatest increases occurred beneath oil blackened surfaces. Evaporation of volatile components is the most significant weathering process in the first two years. Volatiles evaporated faster from surface oil than from oil carried deeper into the soil profile. Microbial degradation has not been observed. The indigenous soil microbial populations responded differently to winter and summer oil applications, ranging from inhibition to stimulation, with stimulation appearing to predominate. Vegetation showed both immediate and long-term damage. Damage was greatest near the top of the slope and in areas with surface oil. Deciduous species showed damage faster than evergreen species.
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    Pages: vii, 67 Seiten , Illustrationen
    Series Statement: CRREL Report 80-29
    Language: English
    Note: CONTENTS Abstract Preface Summary Introduction Methods Site description Oil application Physical characterization Thermal characterization Oil and oily soil characterization Soil microbiological methodology Vegetation Results and discussion Oil movement Effects on permafrost Compositional changes Microbiological responses Oil effects on vegetation Conclusions Recommendations Literature cited Appendix A Physical and thermal information Appendix B Chemical information Appendix C Microbiological information
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  • 32
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    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-79/17
    In: CRREL Report, 79-17
    Description / Table of Contents: Six test roofs of two different slopes — 16.3° and 39.8°, and three different roof coverings — asphalt shingles, cedar shingles, and corrugated aluminum sheeting, were constructed at USACRREL, Hanover, New Hampshire, and were instrumented with thermocouples, heat flow meters, and calibrated gutters. Measurements were recorded for the winters of 1971-72 and 1972-73. The degree of icing and the chronological changes in the snow cover were recorded on 35-mm Kodachrome slides. It was found that eave icing is a sensitive function of the slope, roof covering composi­tion, and solar radiation. The effects of wind were not investigated; the data were screened to remove all informa­tion corresponding to windspeeds over 8 km/h. In order of increasing tendency to form ice dams on the eaves, the roofs were high-slope asphalt, high-slope cedar, high-slope aluminum, low-slope asphalt, low-slope cedar, and low- slope aluminum.
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    Pages: vi, 40 Seiten , Illustrationen
    Series Statement: CRREL Report 79-17
    Language: English
    Note: CONTENTS Abstract Preface Summary Introduction Experimental procedure Description of roofs Meteorological data Procedure Analysis General Temperature profiles Temperature rankings Heat flow Snow depths and meltwater volumes Degree of icing Results and conclusions General Temperature profiles of the roofs Comparative temperatures of roofs by section — rankings Heat flow and accumulation Snow depth, coverage, and meltwater Degree of icing Discussion of the icing problem Literature cited
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  • 33
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    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-82/14
    In: CRREL Report, 82-14
    Description / Table of Contents: A comparative study was made of design criteria and analytical methods for footings and pile foundations on perma­frost employed in U.S.S.R. Design Code SNiP II-18-76 (1977) and U.S. Army Cold Regions Research and Engineering Laboratory Special Report 80-34 developed in the early 1970's by the U.S. Army Corps of Engineers and published in 1980. The absence of adequate constitutive equations for frozen soils and of rigorous solutions of the boundary prob­lems has made it necessary to incorporate (explicitly or implicitly) various safety factors in the foundation analyses. From the review it is concluded that the principal difference between these practices is in the assessment and application of appropriate values of safety factors, which leads to a substantial discrepancy in the dimensions and cost of footings and pile foundations in permafrost.
    Type of Medium: Series available for loan
    Pages: iv, 20 Seiten , Illustrationen
    Series Statement: CRREL Report 82-14
    Language: English
    Note: CONTENTS Abstract Preface Introduction U.S.S.R. system of standards U.S.S.R. Design Code SNiP 11-18-76 (1977) subsoils and foundations on permafrost General regulations Classification of soils Basic regulations for foundation design Analysis of subsoils and foundations Design of foundations for special soil conditions, and appendices SR 80-34 (1980) design and construction of foundations in areas of deep seasonal frost and permafrost General information Foundation design Conclusions Literature cited
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  • 34
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    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
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    Call number: ZSP-201-82/12
    In: CRREL Report, 82-12
    Description / Table of Contents: From a high-quality set of velocity, temperature, and humidity profiles collected upwind and downwind of a step change in surface roughness, temperature, and moisture, we have calculated upwind and downwind values of the heat fluxes and friction velocity. The surface change is from smooth to rough; upwind, the sensible heat flux is upward and the latent heat flux is zero; downwind, the surface is well-watered so that the latent heat flux is upward while the sensible heat flux is downward. The downwind latent heat flux in this fetch-limited flow obeys NL=0.08 Rx 0.76 where NL is the latent heat Nusselt number and Rx is the fetch Reynolds number, a parameter for characterizing fetch-limited flows. Because this relation is virtually the same as one found to describe the sensible heat and condensate fluxes over arctic leads, we conclude that the Nusselt numbers nondimensionalizing scalar fluxes are the same for a given fetch Reynolds number when boundary conditions are similar.
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    Pages: vii, 18 Seiten , Illustrationen
    Series Statement: CRREL Report 82-12
    Language: English
    Note: CONTENTS Abstract Preface List of symbols Introduction Upwind: flux gradient method Downwind: integral method ResulIts Energy budget Latent heat flux Surface stress Downwind humidity profiles Discussion Conclusions Literature cited
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  • 35
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    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-202-99
    In: Research report / Cold Regions Research and Engineering Laboratory, 99
    Description / Table of Contents: Summary: A study of how age hardening affects the various mechanical properties of processed snow was made. A description of how the age hardening process is affected by the variables of density, temperature, grain size, and shape is given. An empirical equation relating creep rate to stress, age, and density was obtained. The study also shows that the various mechanical properties are related to age by an exponential function.
    Type of Medium: Series available for loan
    Pages: iv, 12 Seiten , Illustrationen
    Series Statement: Research report / Cold Regions Research and Engineering Laboratory 99
    Language: English
    Note: CONTENTS Preface Summary Introduction Experimental facilities Experimental in-place measurements Density and homogeneity of processed snow Ram hardness Temperature measurements Mechanical properties Unconfined compressive strength Stress-strain relationships in unconfined compress ion Creep in unconfined compression Tensile strength Discussion of results References
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  • 36
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    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-82/21
    In: CRREL Report, 82-21
    Description / Table of Contents: The acoustic emission response from fine-grained polycrystalline ice subjected to constant compressive loads was examined. A number of tests were conducted with the nominal stress ranging from 0.8 to 3.67 MPa at a temperature of -5 C. The acoustic emission response was recorded and the data are presented with respect to time and strain. The source of acoustic emissions in ice is considered in terms of the formation of both microfractures and visible fractures that develop without catastrophic failure of the ice. A model to describe the acoustic emission response is developed.
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    Pages: iv, 15 Seiten , Illustrationen
    Series Statement: CRREL Report 82-21
    Language: English
    Note: CONTENTS Abstract Preface Introduction Background Experimental procedures Ice specimens Mechanical test equipment Acoustic emission equipment Data recording Acoustic emission sources in ice Acoustic events and visible fracturing Source mechanisms Tests on ice single crystals General acoustic emission response Analysis of data Transient response Steady-state response Amplitude distribution Combined transient and steady-state response in the time domain Discussion Summary Literature cited
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    Uppsala
    Associated volumes
    Call number: SR 93.0768(779)
    In: Sveriges Geologiska Undersökning
    Type of Medium: Series available for loan
    Pages: 31 S.
    ISBN: 9171582223
    Series Statement: Sveriges geologiska undersökning : Ser. C, Avhandlingar och uppsatser 779
    Language: English
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  • 38
    Call number: SR 93.0768(757)
    In: Sveriges Geologiska Undersökning
    Type of Medium: Series available for loan
    Pages: 57 S. + 1 Kt.-Beil., 1 Beil.
    ISBN: 9171581626
    Series Statement: Sveriges geologiska undersökning : Ser. C, Avhandlingar och uppsatser 757
    Language: English
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  • 39
    Call number: SR 93.0768(772)
    In: Sveriges Geologiska Undersökning
    Type of Medium: Series available for loan
    Pages: 40 S.
    ISBN: 9171581898
    Series Statement: Sveriges geologiska undersökning : Ser. C, Avhandlingar och uppsatser 772
    Language: English
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  • 40
    Call number: SR 93.0768(758)
    In: Sveriges Geologiska Undersökning
    Type of Medium: Series available for loan
    Pages: 33 S.
    ISBN: 9171581634
    Series Statement: Sveriges geologiska undersökning : Ser. C, Avhandlingar och uppsatser 758
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  • 41
    Call number: SR 93.0768(785)
    In: Sveriges Geologiska Undersökning
    Type of Medium: Series available for loan
    Pages: 202 S.
    ISBN: 9171582398
    Series Statement: Sveriges geologiska undersökning : Ser. C, Avhandlingar och uppsatser 785
    Language: English
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  • 42
    Call number: SR 93.0768(787)
    In: Sveriges Geologiska Undersökning
    Type of Medium: Series available for loan
    Pages: 40 S.
    ISBN: 9171582444
    Series Statement: Sveriges geologiska undersökning : Ser. C, Avhandlingar och uppsatser 787
    Language: English
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  • 43
    Call number: SR 93.0768(791)
    In: Sveriges Geologiska Undersökning
    Type of Medium: Series available for loan
    Pages: 54 S.
    ISBN: 9171582576
    Series Statement: Sveriges geologiska undersökning : Ser. C, Avhandlingar och uppsatser 791
    Language: English
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  • 44
    Call number: SR 93.0768(794)
    In: Sveriges Geologiska Undersökning
    Type of Medium: Series available for loan
    Pages: 288 S.
    ISBN: 9171582673
    Series Statement: Sveriges geologiska undersökning : Ser. C, Avhandlingar och uppsatser 794
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  • 45
    Call number: SR 93.0768(793)
    In: Sveriges Geologiska Undersökning
    Type of Medium: Series available for loan
    Pages: 24 S.
    ISBN: 9171582622
    Series Statement: Sveriges geologiska undersökning : Ser. C, Avhandlingar och uppsatser 793
    Language: English
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  • 46
    Call number: SR 93.0768(820)
    In: Sveriges Geologiska Undersökning
    Type of Medium: Series available for loan
    Pages: 79 S.
    ISBN: 9171584412
    Series Statement: Sveriges geologiska undersökning : Ser. C, Avhandlingar och uppsatser 820
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  • 47
    Call number: SR 93.0768(822)
    In: Sveriges Geologiska Undersökning
    Type of Medium: Series available for loan
    Pages: 20 S.
    ISBN: 9171584641
    Series Statement: Sveriges geologiska undersökning : Ser. C, Avhandlingar och uppsatser 822
    Language: English
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  • 48
    Call number: SR 93.0768(816)
    In: Sveriges Geologiska Undersökning
    Type of Medium: Series available for loan
    Pages: 42 S. + 5 Kt.-Beil.
    ISBN: 9171584129
    Series Statement: Sveriges geologiska undersökning : Ser. C, Avhandlingar och uppsatser 816
    Language: English
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  • 49
    Call number: SR 93.0768(796)
    In: Sveriges Geologiska Undersökning
    Type of Medium: Series available for loan
    Pages: 79 S. + 1 Beil.
    ISBN: 9171582754
    Series Statement: Sveriges geologiska undersökning : Ser. C, Avhandlingar och uppsatser 796
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  • 50
    Call number: SR 93.0768(753)
    In: Sveriges Geologiska Undersökning
    Type of Medium: Series available for loan
    Pages: 62 S.
    ISBN: 9171581588
    Series Statement: Sveriges geologiska undersökning : Ser. C, Avhandlingar och uppsatser 753
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  • 51
    Call number: SR 93.0768(756)
    In: Sveriges Geologiska Undersökning
    Type of Medium: Series available for loan
    Pages: 38 S.
    ISBN: 9171581618
    Series Statement: Sveriges geologiska undersökning : Ser. C, Avhandlingar och uppsatser 756
    Language: English
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  • 52
    Call number: SR 93.0768(781)
    In: Sveriges Geologiska Undersökning
    Type of Medium: Series available for loan
    Pages: 43 S.
    ISBN: 9171582312
    Series Statement: Sveriges geologiska undersökning : Ser. C, Avhandlingar och uppsatser 781
    Language: English
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  • 53
    Call number: SR 93.0768(783)
    In: Sveriges Geologiska Undersökning
    Type of Medium: Series available for loan
    Pages: 67 S.
    ISBN: 9171582339
    Series Statement: Sveriges geologiska undersökning : Ser. C, Avhandlingar och uppsatser 783
    Language: English
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  • 54
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    Uppsala
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    Call number: SR 93.0768(784)
    In: Sveriges Geologiska Undersökning
    Type of Medium: Series available for loan
    Pages: 51 S.
    ISBN: 9171582347
    Series Statement: Sveriges geologiska undersökning : Ser. C, Avhandlingar och uppsatser 784
    Language: English
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  • 55
    Call number: SR 93.0767(73)
    In: Sveriges geologiska undersökning. Serie Ca, Avhandlingar och uppsater
    Type of Medium: Series available for loan
    Pages: 70 S.
    ISBN: 917158465X
    Series Statement: Sveriges geologiska undersökning : Ser. Ca, Avhandlingar och uppsatser 73
    Language: English
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  • 56
    Call number: SR 93.0767(79)
    In: Sveriges geologiska undersökning. Serie Ca, Avhandlingar och uppsater
    Type of Medium: Series available for loan
    Pages: 42 S.
    ISBN: 9171585044
    Series Statement: Sveriges geologiska undersökning : Ser. Ca, Avhandlingar och uppsatser 79
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  • 57
    Call number: SR 93.0767(81)
    In: Sveriges geologiska undersökning. Serie Ca, Avhandlingar och uppsater
    Type of Medium: Series available for loan
    Pages: 380 S. + 1 Kt.-Beil., 1 Beil.
    ISBN: 9171585184
    Series Statement: Sveriges Geologiska Undersökning : Ser. Ca, Research papers 81
    Language: English
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  • 58
    Call number: SR 93.0768(778)
    In: Sveriges Geologiska Undersökning
    Type of Medium: Series available for loan
    Pages: 105 S. + 1 Kt.-Beil.
    ISBN: 9171582215
    Series Statement: Sveriges geologiska undersökning : Ser. C, Avhandlingar och uppsatser 778
    Language: English
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  • 59
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    Uppsala
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    Call number: S 90.0939(31)
    In: Report
    Type of Medium: Series available for loan
    Pages: 20 S.
    Series Statement: Report / University of Uppsala, Institute of Geophysics 31
    Language: English
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  • 60
    Call number: S 93.0767(76)
    In: Sveriges geologiska undersökning. Serie Ca, Avhandlingar och uppsater
    Type of Medium: Series available for loan
    Pages: 47 S. + 1 Beil.
    ISBN: 9171584900
    ISSN: 0348-1352
    Series Statement: Sveriges geologiska undersökning : Ser. Ca, Avhandlingar och uppsatser 76
    Language: English
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  • 61
    Call number: SR 93.0767(51)
    In: Sveriges geologiska undersökning. Serie Ca, Avhandlingar och uppsater
    Type of Medium: Series available for loan
    Pages: 28 S.
    ISBN: 917158238X
    Series Statement: Sveriges geologiska undersökning : Ser. Ca, Avhandlingar och uppsatser 51
    Language: English
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  • 62
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    Uppsala
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    Call number: SR 93.0767(56)
    In: Sveriges geologiska undersökning. Serie Ca, Avhandlingar och uppsater
    Type of Medium: Series available for loan
    Pages: 49 S.
    ISBN: 9171583343
    Series Statement: Sveriges geologiska undersökning : Ser. Ca, Avhandlingar och uppsatser 56
    Language: English
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  • 63
    Call number: SR 93.0767(77)
    In: Sveriges geologiska undersökning. Serie Ca, Avhandlingar och uppsater
    Type of Medium: Series available for loan
    Pages: 49 S.
    ISBN: 9171584927
    Series Statement: Sveriges geologiska undersökning : Ser. Ca, Avhandlingar och uppsatser 77
    Language: English
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  • 64
    Call number: SR 93.0767(78)
    In: Sveriges geologiska undersökning. Serie Ca, Avhandlingar och uppsater
    Type of Medium: Series available for loan
    Pages: 59 S.
    ISBN: 9171584951
    Series Statement: Sveriges geologiska undersökning : Ser. Ca, Avhandlingar och uppsatser 78
    Language: English
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  • 65
    Call number: SR 93.0767(68)
    In: Sveriges geologiska undersökning. Serie Ca, Avhandlingar och uppsater
    Type of Medium: Series available for loan
    Pages: 55 S.
    ISBN: 9171584269
    Series Statement: Sveriges geologiska undersökning : Ser. Ca, Avhandlingar och uppsatser 68
    Language: English
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  • 66
    Call number: SR 93.0767(74)
    In: Sveriges geologiska undersökning. Serie Ca, Avhandlingar och uppsater
    Type of Medium: Series available for loan
    Pages: 91 S.
    ISBN: 9171584757
    Series Statement: Sveriges geologiska undersökning : Ser. Ca, Avhandlingar och uppsatser 74
    Language: English
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  • 67
    Call number: M 96.0114
    In: Rapporter och meddelanden / Sveriges Geologiska Undersökning
    Type of Medium: Monograph available for loan
    Pages: 30 S.
    ISBN: 9171585273
    ISSN: 0349-2176
    Series Statement: Rapporter och meddelanden / Sveriges Geologiska Undersökning nr. 76
    Classification:
    Regional Geology
    Language: English
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  • 68
    Call number: M 17.90889
    Type of Medium: Monograph available for loan
    Pages: VI, 180 S. , Ill., graph. Darst.
    ISBN: 9150605046
    Language: English
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  • 69
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-83/12
    In: CRREL Report, 83-12
    Description / Table of Contents: This paper documents the development and verification of two finite difference models that solve the general two-dimensional form of the heat conduction equation, using the alternative-direction implicit method. Both can handle convective, constant flux, specified temperature and semi-infinite boundaries. The conducting medium may be composed of many materials. The first program, ADI, solves for the case where no change of state occurs. ADIPC solves for case where a freeze/thaw change of phase may occur, using the apparent heat capacity method. Both models are verified by comparison to analytical results.
    Type of Medium: Series available for loan
    Pages: 74 Seiten , Illustrationen
    Series Statement: CRREL Report 83-12
    Language: English
    Note: CONTENTS Abstract Preface Introduction Finite differences applied to heat transfer Heat conduction equation Boundary conditions Phase change Computer program ADDATA, the data subroutine TRIDIG, the matrix solver ISOTHM, the isotherm finider ADI, main program ADEPC, main program Verification of ADI Comparison of ADI with analytical results Comparison of ADI with experimental results Verification of ADIPC Comparison of ADIPC with analytical results-the Neumann solution Comparison of ADIPC with analytical results-two-dimensional phase change verification User instruction for ADI User instruction for ADIPC Conclusions Literature cited Appendix A. Program INFSUM and sample input and output for program ADI Appendix B. Program ADIPC and sample input and output
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  • 70
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    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-83/13
    In: CRREL Report, 83-13
    Description / Table of Contents: A review on past experimental and theoretical work indicates a need for additional experimentation to characterize the response of snow to inelastic pressure waves. Pressure data from previously conducted explosion tests are analyzed to estimate the elastic limit of snow of 400 -kg/cu m density to be about 36 kPa. This pressure corresponds to a scaled distance of 1.6 m/cu.rt.kg for charges fired beneath the surface of the snow, and to a scaled distance of 1.2 m/cu.rt.kg for charges fired in the air. The effects of a snow cover on the method of clearing a minefield by using an explosive charge fired in the air above the snow surface are also discussed and recommendations are given for further work in this area. Explosive pressure data are used to estimate the maximum effective scaled radius for detonating buried mines at shallow depth to be 0.8 m/cu.rt.kg. Fuel-air explosive will increase this effective radius significantly because of the increase in the size of the source region.
    Type of Medium: Series available for loan
    Pages: 33 Seiten , Illustrationen
    Series Statement: CRREL Report 83-13
    Language: English
    Note: CONTENTS Abstract Preface List of symbols Introduction Objectives Background Problems in describing the response of snow to an applied stress Methods of determining the dynamic behavior of materials Review of previous studies on snow Experimental measurements on snow Summary of snow experiments Theoretical studies Confirmation of the theory Discussion Applications Recommendations Summary Literature cited Appendix A. Selected data from Wisotski and Snyder (1966) Appendix B. Pressure data from Livingston (1964)
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  • 71
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    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-83/11
    In: CRREL Report, 83-11
    Description / Table of Contents: Investigations of ground radar performance over thawed and seasonally frozen silts, and sands and gravels containing artificial and natural reflectors were carried out in Alaska. The radar emitted 5-10 ns pulses, the center frequency of which was approximately 150 MHz. The artificial reflectors were metal sheets and discs and the natural reflectors were the groundwater table and interfaces between frozen and thawed material. The water table was profiled at three sites where the subsurface material was coarse-grained alluvium. Dielectric constants of 16 to 18 were measured for the thawed silts, 6 to 7 for the frozen silts and 3 to 9 for the sands and gravels. Signal penetration in the thawed high moisture content silts may be achieved only by use of a lower frequency radar, whereas in the sands and gravels greater depths may be detected with more sophisticated signal processing.
    Type of Medium: Series available for loan
    Pages: 16 Seiten , Illustrationen
    Series Statement: CRREL Report 83-11
    Language: English
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  • 72
    Call number: ZSP-201-83/22
    In: CRREL Report, 83-22
    Description / Table of Contents: A new experimental method for measuring the soil-water diffusivity of frozen soil under isothermal conditions is introduced. The theoretical justification of the method is presented and the feasibility of the method is demonstrated by experiments conducted using marine-deposited clay. The measured values of the soil-water diffusivity are found comparable to reported experimental data.
    Type of Medium: Series available for loan
    Pages: 13 Seiten , Illustrationen
    Series Statement: CRREL Report 83-22
    Language: English
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  • 73
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-83/23
    In: CRREL Report, 83-23
    Description / Table of Contents: The problems associated with measuring stresses in ice are reviewed. Theory and laboratory test results are then presented for a stiff cylindrical sensor made of steel that is designed to measure ice stresses in a biaxial stress field. Loading tests on freshwater and saline ice blocks containing the biaxial ice stress sensor indicate that the sensor has a resolution of 20 kPa and an accuracy of better than 15% under a variety of uniaxial and biaxial loading conditions. Principal stress directions can also be determined within 5 degrees. The biaxial ice stress sensor is not significantly affected by variations in the ice elastic modulus, ice creep or differential thermal expansion between the ice and gauge. The sensor also has a low temperature sensitivity (5 kPa/deg C).
    Type of Medium: Series available for loan
    Pages: 38 Seiten , Illustrationen
    Series Statement: CRREL Report 83-23
    Language: English
    Note: CONTENTS Abstract Preface Introduction Previous work Stress measurements Design considerations Stress sensors Biaxial ice stress sensor Biaxial stress sensor theory Gauge deformation Stresses associated with cylindrical sensors Determination of ice stresses Gauge calibration Evaluation of the biaxial ice stress sensor Temperature sensitivity Biaxial loading test equipment Biaxial loading test results Differential thermal expansion Long-term drift Discussion of test results Conclusions Literature cited
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  • 74
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    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-83/25
    In: CRREL Report, 83-25
    Description / Table of Contents: Ice action on two cylindrical and conical structures, located side by side, was investigated in a small-scale experimental study to determine the interference on the ice forces generated during ice-structure interaction. The proximity of the two structures changes the mode of ice failure, the magnitude and direction of ice forces on the individual structure, and the dominant frequency of ice force variations. Interference effects were determined by comparing the experimental results of tests at different structure spacings.
    Type of Medium: Series available for loan
    Pages: 42 Seiten , Illustrationen
    Series Statement: CRREL Report 83-25
    Language: English
    Note: CONTENTS Abstract Preface Nomenclature Introduction Experimental setup and procedure Results and discussion Cylindrical structures Conical structures Conclusions Literature cited Appendix A: Relationship between flexural strength and in-situ unconfined compressive strength Appendix B: Test data
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  • 75
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    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-87/20
    In: CRREL Report, 87-20
    Description / Table of Contents: The structure and salinity characteristics of saline ice slabs removed from ice sheets grown in an outdoor pool have been studied and related to the complex relative dielectric permittivity measured with free-space transmission techniques at 4.80 and 9.50 GHz. The saline ice closely simulated arctic sea ice in its structural and salinity characteristics, which were regularly monitored in a number of ice sheets grown during the winters of 1983-84 and 1984-85. In-situ transmission measurements at similar frequencies were also made on the ice sheets themselves using antennas located above and beneath the ice. The slab measurements were made during warming from -29° to -2°C on slabs grown during the winter of 1983-84 (4.75 GHz) and during a warming and cooling cycle over a slightly larger temperature range on slabs grown during the winter of 1984-85 (4.80 and 9.50 GHz).
    Type of Medium: Series available for loan
    Pages: v, 41 Seiten , Illustrationen
    Series Statement: CRREL Report 87-20
    Language: English
    Note: CONTENTS Abstract Preface Part I - Structural properties Introduction Experimental setup Analytical techniques Results and discussion 1983-84 experiments 1984-85 experiments Conclusions and recommendations Part Il - Microwave properties Introduction Measurement techniques Results 1983-84 experiments 1984-85 experiments 1984-85 in-situ experiments Discussion Comparison of data Analytical modeling Summary and conclusions Literature cited Appendix A: Dielectric mixing model of sea ice
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  • 76
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-87/22
    In: CRREL Report, 87-22
    Description / Table of Contents: This review discusses problems associated with the anomalous temperature-density relations of water. It covers a) onset of convection, b) temperature structure and natural convective heat transfer, and c) laminar forced convective heat transfer in the water/ice system. The onset of convection in a water/ice system was found to dependent on thermal boundary conditions, not a constant value as in the classical fluids that have a monotonic temperature-density relationship. The water/ice system also exhibits a unique temperature distribution in the melt layer immediately after the critical Rayleigh number is exceeded and soon after it establishes a more or less constant temperature region progressively deepening as the melt layer grows. The constant temperature is approximately 3.2°C for water layers formed from above but varies for melt layers from below. The heat flux across the water/ice interface was found to be a weak power function and to increase linearly with temperature for melted layers from above and below, respectively.
    Type of Medium: Series available for loan
    Pages: vi, 43 Seiten , Illustrationen
    Series Statement: CRREL Report 87-22
    Language: English
    Note: CONTENTS Abstract Preface Nomenclature Introduction Analytical studies on the onset of convection in a horizontal water layer Experimental studies on the onset of convection in a circular horizontal melt layer Temperature structure and heat transfer In a horizontal layer In a circular horizontal melt layer pHeat transfer studies in nonplanar geometries Forced convective heat transfer over a melting surface Discussion and conclusions Onset of convection Temperature structure and natural convective heat transfer Laminar forced convective heat transfer Literature cited
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  • 77
    Call number: ZSP-201-88/1
    In: CRREL Report, 88-1
    Description / Table of Contents: The Cornish-Windsor bridge is the longest covered bridge in the United States and has significant historical value. At a large peak flow, dynamic ice breakup of the Connecticut River can threaten the bridge and cause flood damage in the town of Windsor, Vermont. Throughout the 1985-86 winter we regularly monitored ice conditions, including a midwinter dynamic ice breakup on 27 January. We conducted controlled release tests over the operating range of the turbines at Wilder Dam upstream during both open water and ice cover conditions. These data and observations were analyzed in light of more than 60 years of temperature and discharge records. Our analysis indicates that river regulation presents alternatives for ice management that would minimize the probability of bridge damage and flooding during breakup. The flow can be regulated early in the winter to promote the growth of a stable ice cover, minimizing the total ice production in the reach. In the weeks prior to breakup, sustained releases and above-freezing air temperatures cause melting, weakening and gradual breakup of the ice, greatly reducing the flooding potential. Also, it is possible to produce a controlled ice breakup prior to an imminent natural event at lower stage and discharge. All of these ice control alternatives have associated power production costs.
    Type of Medium: Series available for loan
    Pages: iii, 21 Seiten , Illustrationen
    Series Statement: CRREL Report 88-1
    Language: English
    Note: CONTENTS Abstract Preface Introduction Background Analysis of historical data Field observations Controlled release tests January 1986 ice breakup Connecticut River ice control Minimizing ice production Hydrothermal melting Controlled ice breakup Conclusions Literature cited Appendix A: Detailed ice breakup chronology
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  • 78
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-88/2
    In: CRREL Report, 88-2
    Description / Table of Contents: While many materials undergo phase change at a fixed temperature, soil systems exhibit a definite zone of phase change. The variation of unfrozen water with temperature causes a soil system to freeze of thaw over a finite temperature range. Exact and approximate solutions are given for conduction phase change of plane layers of soil with unfrozen water contents that vary linearly and quadratically with temperature. The temperature and phase change depths were found to vary significantly from those predicted for the constant-temperature or Neumann problem. The thermal conductivity and specific heat of the soil within the mushy zone varied as a function of unfrozen water content. It was found that the effect of specific heat is negligible, while the effect of variable thermal conductivity can be accounted for by a proper choice of thermal properties used in the constant-thermal-property solution.
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    Pages: v, 30 Seiten , Illustrationen
    Series Statement: CRREL Report 88-2
    Language: English
    Note: CONTENTS Abstract Nomenclature Preface Introduction Basic equations Two-zone problems Linear unfrozen water function Quadratic unfrozen water function Three-zone problems Linear unfrozen water function Quadratic unfrozen water function Conclusions Literature cited Appendix A: Derivation of the mushy zone equation Appendix B: Solution of the two-zone problem with a linear t and variable thermal properties
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  • 79
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    Call number: ZSP-201-88/5
    In: CRREL Report, 88-5
    Description / Table of Contents: This report describes the structural analysis of multi-year sea ice samples that were tested in the second phase of a program designed to obtain a comprehensive understanding of the mechanical properties of multi-year sea ice from the Alaskan Beaufort Sea. Each test specimen is classified into one of three major ice texture categories: granular, columnar, or a mixture of columnar and granular ice. The crystallographic orientation, percent columnar ice, and grain size are then evaluated for the granular and/or columnar ice in the sample. Test results are interpreted with respect to these parameters. The overall composition of multi-year ridges is considered, based on the extensive field sampling that was done in the program. The effect of sample orientation on the results is also discussed.
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    Pages: iii, 32 Seiten , Illustrationen
    Series Statement: CRREL Report 88-5
    Language: English
    Note: CONTENTS Abstract Preface Introduction Sample analysis Continuous multi-year ridge core Tested multi-year ridge ice samples Unconfined constant-strain-rate compression tests Confined constant-strain-rate compression tests Uniaxial constant-strain-rate tension tests Discussion Conclusion Literature cited Appendix A: Multi-year ridge sample data
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  • 80
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    Call number: ZSP-201-88/11
    In: CRREL Report, 88-11
    Description / Table of Contents: This study assesses the effects of atmospheric icing on broadcast transmission reflections on two mountains- Mount Mansfield in northern Vermont and Mount Washington in New Hampshire. Experience and theory suggest that antenna ice accretions produce large signal reflections. Correlations between reflection coefficients and ice accretions on Rosemount ice detectors adjacent to antennas were low and occasionally negative. The unexpected correlations may be due to factors not measured, such as antenna tuning, ice type and ice location on the antenna system. Other confounding factors may include ice detector performance and methods used to compute antenna ice accretions from the ice detectors.
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    Pages: iii, 19 Seiten , Illustrationen
    Series Statement: CRREL Report 88-11
    Language: English
    Note: CONTENTS Abstract Preface Introduction Data sources Study location and icing conditions Icing data Antenna reflection data Data preparation Analyses Conclusions Literature cited
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  • 81
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    Call number: ZSP-201-88/14
    In: CRREL Report, 88-14
    Description / Table of Contents: An experimental study covering a mass flow rate ranging from 1.62 to 67.45 g/cm2-s and snow density varying from 0.377 to 0.472 g/cm3 has been conducted. Pressure drops ranging from 0.012 to 2.868 gf/cm2 were recorded. A plot of the friction factor fp vs Rep (defined as the classical Reynolds number Re for fluid flow through conduits) showed a good representation of all the experimental data. The least-squares analysis resulted in an expression of f sub p = 118/Rep to the 1.095 power for snow, in comparison with the expression f sub p = 64/Rep developed for fluid flow through porous media of randomly packed metallic and nonmetallic materials of spherical and nonspherical shapes.
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    Pages: iv, 18 Seiten , Illustrationen
    Series Statement: CRREL Report 88-14
    Language: English
    Note: CONTENTS Abstract Preface Nomenclature Introduction Experimental setup and procedure Experimental results Discussion and conclusions Literature cited
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  • 82
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    Call number: ZSP-201-87/13
    In: CRREL Report, 87-13
    Description / Table of Contents: Thermodynamic properties of electrolyte solutions change rapidly below 25C, but these properties are seldom measured over the low temperature range (below 0C), even though some salt solutions can remain unfrozen to -50C. The heat capacities of concentrated solutions (0.5-0.6 molal) of NaC-H2O were measured from 25C to -40C as part of a study to provide thermodynamic data of salt solutions for use in cold regions chemical and geophysical studies. A differential scanning calorimeter was used to measure specific heat capacity from cooling scans as a function of temperature and concentration. The heat capacity data were fit to the equations of Pitzer and coworkers to obtain activity and osmotic coefficients of NaC and H2O, respectively, below o C. Supercooling of the solutions was encouraged by using a fast scan rate (10d2/minute) so that specific heat could be measured to lower temperatures than would be possible if the solutions were allowed to equilibrate with the solid phases. The solubility of ice was calculated and compared to the experiment freezing point of NaC solutions.
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    Pages: ii, 16 Seiten , Illustrationen
    Series Statement: CRREL Report 87-13
    Language: English
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  • 83
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    Call number: ZSP-201-87/10
    In: CRREL Report, 87-10
    Description / Table of Contents: Uniaxial constant-stress and constant-strain-rate compression tests were conducted on more than 200 remolded, saturated, frozen specimens of Fairbanks silt under various conditions. A series of curves of stress vs strain rate for various temperatures of strain rates ranging from about 6x10-2 to 10-8s-1show a close strength correspondence between the constant-stress and-costant strain-rate tests. All of these "complete" stress vs strain rate curves could not be described by a single power law or exponential equation, indicating that different deformation mechanisms are dominant within different ranges of strainrate Two critical strain rates for distinguishing between the different deformation mechanisms were ob-served to be near 10- 3 and 10-6 s-1 for the medium-dense frozen Fairbanks silt. The former indicates the transition from ductile failure to moderate brittle fracture as strain rate increases, while the latter indicates the transition from dislocation creep to glide creep (by the authors' definition). Based on the change in flow law, two fundamental creeps were classified: short-term creep, which is governed by glide creep, and long-term creep, which is governed by dislocation creep. The failure criterion of frozen silt has a general form of em x tm = Ef, where m depends only on density, and tm is in minutes if m is not 1. The failure strain Ef was not sensitive to temperature and strain rate over a certain range of strain rates, but it was very sensitive to density. Assur's creep model (1980) for ice was used to fit the creep data in this study. It works well for short-term creep but does not fit as well for long-term creep. The rate process theory was applied to the creep data. A very high value of experimental activation energy was obtained for lower stresses, and a very high value of apparent activation energy was observed for higher temperatures. The peak compressive strength was very sensitive to temperature and strain rate but relatively insensitive to density. While the initial tangent modulus is not-sensitive to strain rate, it increases with decreasing temperature and density.
    Type of Medium: Series available for loan
    Pages: vi, 75 Seiten , Illustrationen
    Series Statement: CRREL Report 87-10
    Language: English
    Note: CONTENTS Abstract Preface Introduction Review of previous work Specimen preparation Material Molding Testing procedure and apparatus Test results Definition of strain and stress Definition of creep failure Definition of failure in constant-strain-rate tests Definition of initial yield strength Determination of initial tangent modulus and 50% peak strength modulus Creep behavior General nature of the creep process and the failure mode Minimum creep rate Time to creep failure Relationship between t, and tm Creep failure strain and failure criterion Creep model and prediction of creep strain Strength behavior General stress-strain behavior and failure mode Peak compressive strength Initial yield strength Failure strain Initial yield strain Initial tangent modulus 50% peak strength modulus Correspondence between constant-stress tests and constant-strain-rate tests Conclusions Literature cited Appendix A: Unfrozen water content data Appendix B: Physical properties of samples tested
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  • 84
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    Call number: ZSP-201-82/36
    In: CRREL Report, 82-36
    Description / Table of Contents: Camp construction and drilling activities in 1950 at the East Oumalik drill site in northern Alaska caused extensive degradation of ice-rich, perennially frozen silt and irreversible modification of the upland terrain. In a study of the long-term degradational effects at this site, the near-surface geology was defined by drilling and coring 76 holes (maximum depth of 34 m) in disturbed and undisturbed areas and by laboratory analyses of these cores. Terrain disturbances, including bulldozed roads and excavations, camp structures and off-road vehicle trails, were found to have severely disrupted the site's thermal regime. This led to a thickening of the active layer, melting of the ground ice, thaw subsidence and thaw consolidation of the sediments. Slumps, sediment gravity flows and collapse of materials on slopes bounding thaw depressions expanded the degradation laterally, with thermal and hydraulic erosion removing materials as the depressions widened and deepened with time. Degradational processes became less active after thawed sediments thickened sufficiently to slow the increase in the depth of thaw and permit slope stabilization. The site's terrain is now irregular and hummocky with numerous depressions. Seasonal thaw depths are deeper in disturbed areas than in undisturbed areas and reflect the new moisture conditions and morphology. The severity of disturbance is much greater at East Oumalik than at another old drill site, Fish Creek. The difference results primarily from differences in the physical properties of the sediments, including the quantity and distribution of ground ice.
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    Pages: 42 Seiten , Illustrationen
    Series Statement: CRREL Report 82-36
    Language: English
    Note: CONTENTS Abstract Preface Summary Introduction Methodology Geologic setting Camp construction and occupation Types of disturbance Degradational processes and the effective area of impact Areal effects of disturbance Topography Groundwater, surface water and drainage Sediment properties and near-surface stratigraphy Surficial processes Depth of thaw Comparison to Fish Creek Discussion and conclusions Literature cited
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  • 85
    Call number: ZSP-201-82/26
    In: CRREL Report, 82-26
    Description / Table of Contents: The Caribou-Poker Creeks Research Watershed is a small (101.5-sq km) drainage basin located 48 km northwest of Fairbanks, Alaska. Elevations within the watershed range from 210 to 826 m, and approximately 28% of its area is underlain by permafrost. Climatic differences between the watershed and Fairbanks are primarily due to the higher elevation of the watershed. Generally the watershed climatic sites are warmer in winter and cooler in summer than Fairbanks. Within the watershed the greatest temperature contrasts exist in winter, when the valley-bottom sites are beneath the regional air temperature inversion, and the higher sites are above it. From May through September the total precipitation averages 270 mm, 1.47 times that received at Fairbanks. The annual precipitation is about 1.7 times that of Fairbanks. The historical precipitation record at Fairbanks indicates that summer precipitation was below the long-term normal in eight of the eleven years of watershed measurements (1969-1980); no climatic extremes occurred during this period. An analysis of annual streamflow data showed an inconsistency of baseflow recessions from year to year. The runoff-rainfall ratio for individual summer storms averaged 0.35 for Caribou Creek. Comparisons of spot discharge measurements of predominantly permafrost and non-permafrost subwatersheds showed that permafrost-dominated watersheds have a much flashier response to precipitation than non-permafrost watersheds. A comparison of the annual flow distribution of the watershed indicated that Caribou Creek has lower summer and higher winter discharges per unit area than the Chena or Salcha Rivers.
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    Pages: 42 Seiten , Illustrationen
    Series Statement: CRREL Report 82-26
    Language: English
    Note: CONTENTS Abstract Preface Introduction Setting Geology and soils Vegetation Climate Air temperature Precipitation Hydrology Annual and monthly runoff Individual storms Baseflow recessions Spatial flow variability Temporal flow variability Summary and conclusions Literature cited Appendix A: Station histories
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  • 86
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    Call number: ZSP-201-82/27
    In: CRREL Report, 82-27
    Description / Table of Contents: Recommendations for economical thicknesses for building insulation result from a study of fuel and construction costs of 12 military installations in Alaska. A comparison between the insulation thickness that a building owner might choose today and what he might choose in 20 years indicates a trend for much thicker insulation in the future. An analysis of how much more expensive a building built today with the thickness that would be appropriate 20 years hence indicates only a small penalty in life-cycle costs for the additional insulation. Therefore, a minimum of R-32 walls and R-62 attics is recommended for most of Alaska.
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    Pages: 54 Seiten , Illustrationen
    Series Statement: CRREL Report 82-27
    Language: English
    Note: CONTENTS Abstract Preface Conversion factors Summary Introduction Determining economic thicknesses for insulation Background Analysis method for new construction Analysis method for reinsulating existing construction Sensitivity and longevity of the results Sensitivity Longevity Recommendations Saving money vs. saving energy Energy economics conservation Building energy performance standards Conclusion Literature cited Appendix A: Heating system costs Appendix B: Present worth factors Appendix C: Base case and incremental thermal properties Appendix D: LCC comparison graphs for wall and roof systems Appendix E: Cost penalties for energy conservatism Appendix F: Graphic aid for figuring energy savings thermal improvements
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  • 87
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    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
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    Call number: ZSP-201-82/29
    In: CRREL Report, 82-29
    Description / Table of Contents: Ice grains in a snow cover with a low temperature gradient assume a well-rounded equilibrium form. However, at temperature gradients of 0.1 to 0.2 C/cm (depending somewhat on temperature and snow density), the rounded grains recrystallize into a faceted kinetic growth form. The large temperature gradient must play a decisive role in moving the vapor fast enough to sustain the rapid growth rate associated with the kinetic growth form. Once the large temperature gradient is removed, the grains recrystallize back to the equilibrium form. the recrystallization occurs in either direction without a change in bulk density. The growth of faceted crystals begins at the warmer base of the snow cover where the excess vapor pressure is largest. A transition between the overlying rounded grains moves upward in time. Faceted crystals also grow just below crusts of reduced permeability, where the increased vapor accumulation can sustain the excess vapor pressure neded for kinetic growth. The heat and vapor flows are described using a model based on thermodynamic equilibrium. The temperature distribution is shown to be quasi-linear at steady state in homogeneous snow. The recrystallization of the snow is modeled using the rounded grains as sources and the faceted grains as sinks. In the future this model should be extended to account for different temperatures among the sources and sinks.
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    Pages: 27 Seiten , Illustrationen
    Series Statement: CRREL Report 82-29
    Language: English
    Note: Contents: Abstract Preface Introduction Vapor flow Temperature profile Crystal growth rates Equilibirum versus kinetic growth forms of snow crystals Discussion Summary Literature cited
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  • 88
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    Call number: ZSP-201-82/30
    In: CRREL Report, 82-30
    Description / Table of Contents: Equations are developed that can be used to determine the amount of gas present in sea ice from measurements of the bulk ice density, salinity and temperature in the temperature range o f-2 to -30°C. Conversely these relationships can be used to give the density of sea ice as a function of its temperature and salinity, considering both the presence of gas and of solid salts in the ice. Equations are also given that allow the calculation of the gas and brine volumes in the ice at temperatures other than that at which the bulk density was determined.
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    Pages: 13 Seiten , Illustrationen
    Series Statement: CRREL Report 82-30
    Language: English
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  • 89
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    Call number: ZSP-201-82/31
    In: CRREL Report, 82-31
    Description / Table of Contents: Information on sea ice conditions in the Bering Strait and the icefoot formation around Fairway Rock, located in the strait, is presented. Cross-sectional profiles of Fairway Rock and the relief of the icefoot are given along with theoretical analyses of the possible forces active during icefoot formation. It is shown that the ice cover most likely fails in flexure as opposed to crushing or buckling, as the former requires less force. Field observations reveal that the Fairway Rock icefoot is massive, with ridges up to 15 m high, a seaward face only 20 degrees from vertical, and interior ridge slopes averaging 33 degrees. The icefoot is believed to be grounded and its width ranges from less than 10 to over 100 m.
    Type of Medium: Series available for loan
    Pages: 44 Seiten , Illustrationen
    Series Statement: CRREL Report 82-31
    Language: English
    Note: CONTENTS Abstract Preface Introduction Bering Strait Field reconnaissance Estimation of ice forces on Fairway Rock 1. Creep deformation 2. Crushing failure 3. Flexural failure 4. Forces required to form floating or grounded pressure ridges along therock or to pile ice on the beaches 5. Buckling failure Driving forces Angle of internal friction of sea ice Summary Literature cited Appendix A: April 1982 field observations at Fairway Rock
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  • 90
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    Call number: ZSP-201-82/33
    In: CRREL Report, 82-33
    Description / Table of Contents: Arctic sea ice is freckled with melt ponds during the ablation season; Antarctic sea ice has few, if any. On the basis of a simple surface heat budget, we investigate the meteorological conditions necessary for the onset of surface melting in an attempt to explain these observations. The low relative humidity associated with the relatively dry winds off the continent and an effective radiation parameter smaller than that characteristic of the Arctic are primarily responsible for the absence of melt features in the Antarctic. Together these require a surface-layer air temperature above 0 C before Antarctic sea ice can melt. A ratio of the bulk transfer coefficients C sub H/C sub E less than 1 also contributes to the dissimilarity in Arctic and Antarctic ablation seasons. The effects of wind speed and of the sea-ice roughness on the absolute values of C sub H and C sub E seem to moderate regional differences, but final assessment of this hypothesis awaits better data, especially from the Antarctic.
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    Pages: 16 Seiten , Illustrationen
    Series Statement: CRREL Report 82-33
    Language: English
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  • 91
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    Call number: ZSP-201-82/32
    In: CRREL Report, 82-32
    Description / Table of Contents: Low-frequency (10 Hz) volcanic earthquakes originate at a wide range of depths and occur before, during, and after magmatic eruptions. The characteristics of these earthquakes suggest that they are not typical tectonic events. Physically analogous processes occur in hydraulic fracturing of rock formations, low-frequency icequakes in temperate glaciers, and autoresonance in hydroelectric power stations. We propose that unsteady fluid flow in volcanic conduits is the common source mechanism of low-frequency volcanic earthquakes (tremor). The fluid dynamic source mechanism explains low-frequency earthquakes of arbitrary duration, magnitude, and depth of origin, as unsteady flow is independent of physical properties of the fluid and conduit. Fluid transients occur in both low-viscosity gases and high-viscosity liquids. A fluid transient analysis can be formulated as generally as is warranted by knowledge of the composition and physical properties of the fluid, material properties, geometry and roughness of the conduit, and boundary conditions. To demonstrate the analytical potential of the fluid dynamic theory, we consider a single-phase fluid, a melt of Mount Hood andeside at 1250 deg C, in which significant pressure and velocity variations occur only in the longitudinal direction.
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    Pages: 15 Seiten , Illustrationen
    Series Statement: CRREL Report 82-32
    Language: English
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  • 92
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    Call number: ZSP-201-82/34
    In: CRREL Report, 82-34
    Description / Table of Contents: The ice discharge through an opening in an ice control structure was documented to be a function of the floe size, ice type, ice floe conditions and vessel direction. The model data for the average ice discharge per vessel transit scaled to prototype values compared favorably with data taken at the St. Marys River ice control structure (ICS). The model results of the force measurements were also consistent with data taken at the St. Marys ICS. The dynamic loading conditions were independent of vessel direction. The dynamic loading to the structure using 3 types of ice (plastic, natural and urea-doped) showed a considerable difference in their means and standard deviations. The urea-doped ice was evaluated for dynamic loading conditions, and reasonable peak values of 3 to 5 times the mean load at each measuring position were recorded, independent of vessel direction. It appears that synthetic random ice floes may be used in model studies where ice discharge through an opening in a structure needs to be documented. This study shows the synthetic random ice floe discharge to fall reasonably within the values obtained for natural ice discharge for both rafted and non-rafted ice fields above the ICS. However, the question of whether synthetic ice can be used for analyzing force distributions and dynamic force loading criteria cannot be fully answered at this time because the load distributions of the synthetic and natural floes appear to differ.
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    Pages: 68 Seiten , Illustrationen
    Series Statement: CRREL Report 82-34
    Language: English
    Note: CONTENTS Abstract Preface Introduction Scope of work Ice discharge from Lake Huron into St. Clair River Water velocity profiles at Port Huron Ice conditions Physical model Basis for selection Description Instrumentation Model ice control structure Open water calibration Open water tests Experimental procedures and techniques Ice cover calibration Ice control structure orientation Analysis of ice discharge due to ship transits Natural ice Synthetic ice Forces on the ice control structure Static measurements Dynamic force measurements Potential additional shear stresses Anticipated ice conditions with ICS Conclusions Literature cited Appendix A. Application of model results Appendix B. Suggested additional studies Appendix C. Derivation of ice discharge
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  • 93
    Call number: ZSP-201-86/3
    In: CRREL Report, 86-3
    Description / Table of Contents: Experiments to study the melting of a horizontal ice sheet with a flow of water above it were conducted in a 35 m long refrigerated flume with a cross section of 1.2x1.2 m. Water depth, temperature, and velocity were varied as well as the temperature and initial surface profile of the ice sheet. The heat transfer regimes were found to consist of forced turbulent flow at high Reynolds numbers with a transition to free convection heat transfer. There was no convincing evidence of a forced laminar regime. The data were correlated for each of the regimes, with the Reynolds number, Re, or the Grashof number combined with the Reynolds number as Gr/Re to the 2.5 power used to characterize the different kinds of heat transfer. For water flowing over a horizontal ice sheet, the melting heat flux, for low flow velocities, was not found to drop below the value for the free convection case-488.5 W/sq m-as long as the water temperature exceeds 3.4 C. This is significant since the free convection melt values far exceed those for laminar forced convection. At the low flow velocities, the melting flux was not dependent upon the fluid temperature until the water temperature dropped below 3.4 C, when q sub c = 135.7 (Delta T). In general, the heat transfer was found to significantly exceed that of non-melting systems for the same regimes. This was attributed to increased free stream turbulence, thermal instability due to the density maximum of water near 4 C, and the turbulent eddies associated with the generation of a wavy ice surface during the melting.
    Type of Medium: Series available for loan
    Pages: vii, 85 Seiten , Illustrationen
    Series Statement: CRREL Report 86-3
    Language: English
    Note: CONTENTS Abstract Preface Nomenclature Introduction Non-melting heat transfer relations for horizontal surfaces Heat transfer for melting horizontal ice sheets Instrument setup, data acquisition and test procedures General Instrumentation Data acquisition Computer software Test procedures Data output from computer Equations used for data analysis Control volume and melting surface Control of variables Error analysis Experimental results and discussion Wave formation Temperature and velocity profiles in open channel flow Correlation of data Summary Literature cited Appendix A: Conversion equations for data acquisition equipment Appendix B: Computer code for data acquisition and analysis Appendix C: Typical test output Appendix D: Thermal properties of water and ice Appendix E: Error analysis Appendix F: Summary of test conditions Appendix G: Experimental data and calculated quantities, with inlet length
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  • 94
    Call number: ZSP-201-86/6
    In: CRREL Report, 86-6
    Description / Table of Contents: Short-pulse radar profiles and waveform traces were recorded over natural, freshwater ice sheets and an artificially made, 1.6-m-diameter column of brash ice. The purpose was to study the feasibility of this type of radar to detect ice thickness, determine ice properties and distinguish ice forms. The radar utilized two antennas: one with a spectrum centered near 900 MHz and a second more powerful one near 700 MHz. Distinct top and bottom reflections from several ice sheets were produced by both antennas, but the value of dielectric permittivity calculated from the time of delay of the reflections varied between sheets as one ice sheet was ready to candle and contained free water. The brash ice distorted signals and allowed no discernible bottom return. The lower frequency antenna also gave returns from the lake bottom (separated from the ice bottom by about 1 m of water), which could allow ice thickness to be determined indirectly. The report concludes that these antennas can be used to determine sheet ice thickness and to supply information to help in the detection of brash ice. The water content of an ice sheet may also be estimated if independent studies show a correlation between dielectric permittivity and free water content.
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    Pages: iv, 15 Seiten , Illustrationen
    Series Statement: CRREL Report 86-6
    Language: English
    Note: CONTENTS Abstract Preface Introduction Materials and methods Sites and site preparation Results and discussion Lake Morey Post Pond Conclusions and recommendations Literature cited
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  • 95
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    Call number: ZSP-201-86/7
    In: CRREL Report, 86-7
    Description / Table of Contents: Nitrogen control in the form of ammonia removal or conversion is required, or will be required, for a significant number of military wastewater treatment systems. This reportpresents a summary of engineering criteria for those processes in most common use at military facilities in the cold regions. These processes include: trickling filters, treatmentponds, rotating biological contactors (RBC) and activated sludge. A design example is presented for each case. All four processes can achieve significant levels of ammonia removalor conversion. If ammonia discharge limits are 0.5 mg/L or less it may be necessary to use the activated sludge process. Trickling filters or RBC units are recommended for higher(〉 1 mgIL) discharge limits. Pond systems are suitable for seasonal ammonia removal incold climates.
    Type of Medium: Series available for loan
    Pages: iv, 29 Seiten , Illustrationen
    Series Statement: CRREL Report 86-7
    Language: English
    Note: CONTENTS Abstract Preface Introduction Background and theory Trickling filters Introduction Design procedure Design example Winter operations Pond systems Introduction Design procedure Design example Winter operations Rotating biological contactors Introduction Design procedure Design example Winter operations Activated sludge systems Introduction Design procedure Design example Winter operations Comparison of alternatives Conclusions Literature cited
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  • 96
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    Call number: ZSP-201-86/8
    In: CRREL Report, 86-8
    Description / Table of Contents: In this work, numerical computations of heat transfer for freezing a shaft wall have been conducted. Both fixed mesh and deforming mesh finite-element methods are used. In the fixed mesh method, latent heat effects are accounted for through a δ function in the apparent heat capacity. In the deforming mesh method, an automatic mesh-generation technique with transfinite mappings is used, and in this method two different approaches are taken to evaluate the movement of the interface. The freeze-pipes are considered as point sources with irregular distribution. The advancement of the inner and outer boundaries of the frozen wall is found to be in agreement with the previously computed results
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    Pages: iii, 31 Seiten , Illustrationen
    Series Statement: CRREL Report 86-8
    Language: English
    Note: CONTENTS Abstract Preface Introduction Basic finite-element formulas Description of problem Finite-element equation-fixed mesh Finite-element equation-deforming mesh Transfinite mapping technique Computations and conclusions Literature cited Appendix A : Point heat sources Appendix B: Evaluation of the integral including latent heat (fixed mesh) Appendix C: Specification of [K] -deforming mesh Appendix D: Specifying δΤ/δn and the direction of mj for method I Appendix E: Procedures of method 2 Appendix F: Explanation of programs
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  • 97
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    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-76/38
    In: CRREL Report, 76-38
    Description / Table of Contents: Current methods for evaluation of the moisture absorption of plastic insulations (ASTM-C-272-53 and ASTM-C-355-64) due to vapor pressure gradients or immersion rely on short time periods to predict long term performance. This procedure may not provide accurate information on performance since in practice insulations may absorb more moisture than these tests indicate. A series of tests were conducted on extruded polystyrene roof insulation that had been in place, exposed to environmental moisture and pressure gradients, for a maximum of 36 months. Results indicate that moisture absorption of 1.5% by volume can be expected in the field.
    Type of Medium: Series available for loan
    Pages: iv, 21 Seiten , Illustrationen
    Series Statement: CRREL Report 76-38
    Language: English
    Note: CONTENTS Abstract Preface Conversion factors: U.S. customary to metric (SI) units of measurement Introduction Principal features of a protected membrane roof system Reported advantages of a protected membrane roof system Study sites Stevens Hall, University of Alaska, Fairbanks Building 41 5, University of Alaska, Fairbanks Building 1053, Ft. Wainwright, Alaska Gruening Building, University of Alaska, Fairbanks Consortium Library and K Building, University of Alaska, Anchorage CRREL Laboratory, Hanover, New Hampshire Resources Building, University of Alaska, Fairbanks Insulation properties Sampling Results Bulksamples Sliced samples Conclusions and recommendations Literature cited Appendix A. Moisture contents Appendix B. Photographs
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  • 98
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    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-86/5
    In: CRREL Report, 86-5
    Description / Table of Contents: This work presents the results of a study to examine the effects of grain size of internal microfractures in polycrystalline ice. Laboratory-prepared specimens were tested under uniaxial, constant-load creep conditions at -5 C. Grain size ranged from 1.5 to 6.0 mm. This range of grain size, under an initial creep stress of 2.0 MPa, led to a significant change in the character of deformation. The finest-grained material displayed no internal cracking and typically experienced strains of 10 to the minus 2nd power at the minimum creep rate epsilon. The coarse-grained material experienced severe cracking and a drop in the strain at epsilon min to approximately 4x10 to the minus 3rd power. Extensive post-test optical analysis allowed estimation of the size distribution and number of microcracks in the tested material. These data led to the development of a relationship between the average crack size and the average grain size. Additionally, the crack size distribution, when normalized to the grain diameter, was very similar for all specimens tested. The results indicate that the average crack size is approximately one-half the average grain diameter over the stated grain size range. A dislocation pileup model is found to adequately predict the onset of internal cracking. The work employed acoustic emission techniques to monitor the fracturing rate occurred. Other topics covered in this report include creep behavior, crack healing, the effect of stress level on fracture size and the orientation of cracked grains. Theoretical aspects of the grain size effect on material behavior are also given.
    Type of Medium: Series available for loan
    Pages: v, 79 Seiten , Illustrationen
    Series Statement: CRREL Report 86-5
    Language: English
    Note: CONTENTS Abstract Preface Background Present research in perspective Explanations of the grain-size dependency Grain size effects on the ductile to brittle transition Nucleation mechanisms and modeling Characteristic size of nucleated crack Cracking in ice Detection of internal fracturing by acoustic emission techniques Test methods Specimen preparation Creep testing apparatus Crack length and crack density measurements Crack healing measurements Thin section photographs Grain size determination Acquisition of acoustic emission data Presentation of results Specimen characteristics Microcrack measurements Creep behavior Crack healing Slip plane length distribution Acoustic emission observations Grain orientation Analysis and discussion Thick section observations The grain size vs crack size relationship Crack nucleation condition Crack density and specimen strain Creep behavior Normalized crack length Location of cracks Acoustic emission activity Summary and conclusions Suggestions for future work Literature cited Appendix A: Crack length histograms Appendix B: Crystal orientations
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  • 99
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-85/5
    In: CRREL Report, 85-5
    Description / Table of Contents: A dynamic-thermodynamic sea ice model is extended to include a full thermodynamic code and a complete multilevel ice thickness distribution. The variable thickness formulation includes a more realistic parameterization of ice ridging than used in previous models. Seasonal simulations have been performed using this model and the results have been analyzed with particular emphasis on examination of the ridge buildup results off the Canadian Archipelago and off the North Slope. This report presents a complete description of this model and discusses progress made on examining and testing the variable thickness extensions.
    Type of Medium: Series available for loan
    Pages: vi, 60 Seiten , Illustrationen
    Series Statement: CRREL Report 85-5
    Language: English
    Note: CONTENTS Abstract Preface Summary Introduction Description of the model Ice thickness equations Heat budget and oceanic boundary layer Analytic examination of the ridge redistribution process Theoretical framework Some specific redistributors Comparison to ridge morphological data Ice strength for different redistributors Numerical simulation results Basin-wide ice thickness and velocity characteristics Ice edge evolution and sensitivity Ice thickness characteristics off the Canadian Archipelago Comparison of observed and simulated ice drift Mass balance characteristics Concluding remarks Literature cited Appendix A: Mechanical redistributor Appendix B: Heat budget code Appendix C: Thickness finite difference code
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  • 100
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-76/44
    In: CRREL Report, 76-44
    Description / Table of Contents: The deformation of wet snow is explained in terms of the thermodynamics of the three phases of water. When deformation by particle rearrangement is fully developed, deformation can occur most rapidly by melting at the particle contacts. The rate of deformation is highly sensitive to the liquid water content, ionic impurity content, particle contact area, and stress level. A model of the hydrostatic deformation of wet snow is constructed, and examples of the deformation of wet snow are given for a variety of conditions. These results are in agreement with existing experimental evidence. The model accurately simulates the transient nature of the deformation and the effect of water content on the quasi-stable density of wet snow subjected to a constant stress.
    Type of Medium: Series available for loan
    Pages: iv, 9 Seiten , Illustrationen
    Series Statement: CRREL Report 76-44
    Language: English
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