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  • Books  (50)
  • Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory  (50)
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  • 1
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    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-82/41
    In: CRREL Report, 82-41
    Description / Table of Contents: Many of the important factors influencing the choice of appropriate aquifer test procedures are presented. The concepts of bias, accuracy and spatial variabil­ity are explained. The definitions of a number of aquifer parameters are devel­oped from basic principles demonstrating the underlying assumptions and limita­tions. The parameters considered are: piezometric head, hydraulic conductiv­ity/intrinsic permeability, flow direction, specific discharge magnitude, transmissivity, volumetric flow rate, total porosity, effective porosity, aver­age linear velocity, storage coefficient, specific yield, dispersion coefficient-aquifer dispersivity. For each parameter several techniques are described, evaluated and ranked in terms of perceived potential accuracy, simplicity and value to contaminant transport studies. It must be stressed, however, that the evaluations are based principally upon theoretical grounds, and not upon actual conduct of the described procedures.
    Type of Medium: Series available for loan
    Pages: iv, 111 Seiten , Illustrationen
    Series Statement: CRREL Report 82-41
    Language: English
    Note: CONTENTS Abstrac Preface Introduction Purpose Scope Concept of accuracy Test selection Definition of parameters Piezometric head Use of piezometers Hydraulic conductivity Flow direction Specific discharge magnitude Transmissivity Volumetric flow rate Porosity Average linear velocity Storage coefficient-specific yield Aquifer dispersivity Parameter estimation techniques Piezometric head Hydraulic conductivity Direction and magnitude of specific discharge vector Transmissivity Volumetric flow rate Total porosity Average linear velocity Storage coefficient Specific yield Effective porosity Aquifer dispersivity-dispersion coefficients Conclusions Literature cited
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  • 2
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    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-82/40
    In: CRREL Report, 82-40
    Description / Table of Contents: The use of explosives to break floating ice sheets is described, and test data are used to develop design curves that predict explosives effects as ice thickness, charge size, and charge depth vary. Application of the curves to practical problems is illustrated by numerical examples. The general features of underwater explosions are reviewed and related to ice blasting. Quasi-static plate theory is considered, and is judged to be inapplicable to explosive cratering of ice plates. The specific energy for optimized ice blasting is found to compare quite favorably with the specific energy of icebreaking ships. All available field data for ice blasting are tabulated in appendices, together with details of the re­gression analyses from which the design curves are generated.
    Type of Medium: Series available for loan
    Pages: iv, 68 Seiten , Illustrationen
    Series Statement: CRREL Report 82-40
    Language: English
    Note: CONTENTS Abstract Preface Introduction General behavior of underwater explosions Regression analysis for ice-blasting data General features of the regression curves Use of the regression curves as design curves for ice blasting Row charges and pattern charges Response of floating ice sheets to underwater explosions Specific energy and “powder factor” Summary and conclusions Literature cited Appendix A: Basic data on ice blasting Appendix B: Scaled input data Appendix C: Initial regression analysis using complete polynomial Appendix D: Regression analysis with two coefficients of the original poly­nomial deleted
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  • 3
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    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-82/42
    In: CRREL Report, 82-42
    Description / Table of Contents: A high-resolution impulse radar profiling system was evaluated for 1) detecting the existence of sea ice which coring has revealed to exist on the bottom of the Ross Ice Shelf at Site J-9, 2) detecting the preferred horizontal c-axis azi-muthal direction of the sea ice crystals, using the voltage amplitude of the radar reflection from the sea ice bottom, and 3) determining the direction of the currents under an Antarctic ice shelf. A field program was conducted consisting of a surface radar survey on the Ross Ice Shelf at Site J-9 and surface and airborne radar profiling on the McMurdo Ice Shelf. The CRREL impulse radar system, operating at a center frequency of either 80 MHz or 20 MHz, was unable to detect the shelf bottom at Site J-9, which drilling revealed to be 416 m below the snow surface. The radar system was used to profile the McMurdo Ice Shelf both from the snow surface and from the air; a shelf thickness of about 275 m was easily detected. Theoretical considerations indicate that the bulk conductivity of the ice shelf at Site J1-9 was higher than originally anticipated, and this limited the radar sounding depth to about 405 m when operating at a frequency of 20 MHz.
    Type of Medium: Series available for loan
    Pages: iv, 19 Seiten , Illustrationen
    Series Statement: CRREL Report 82-42
    Language: English
    Note: CONTENTS Abstract Introduction Profiling system Theoretical considerations Field program Discussion Literature cited
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  • 4
    Call number: ZSP-201-82/39
    In: CRREL Report, 82-39
    Description / Table of Contents: Observations of a 4.4-m-high brine step in the McMurdo Ice Shelf, Antarctica, show that it has migrated about 1.2 km in 4 years. The present brine wave is overriding an older brine-soaked layer. This migration is proof of the dynamic nature of the step, which is the leading edge of a brine wave that originated at the shelf edge after a major break-out of the McMurdo Ice Shelf. The inland boundary of brine penetration is characterized by a series of descending steps that are believed to represent terminal positions of separate intrusions of brine of similar origin. The inland boundary of brine percolation is probably controlled largely by the depth at which brine encounters the firn/ ice transition (43 m). However, this boundary is not fixed by permeability considerations alone, since measurable movement of brine is still occurring at the inland boundary. Freeze-fractionation of the seawater as it migrates throught the ice shelf preferentially precipitates virtually all sodium sulfate, and concomitant removal of water by freezing in the pore spaces of the infiltrated firm produces residual brines approximately six times more concentrated than the original seawater.
    Type of Medium: Series available for loan
    Pages: v, 35 Seiten , Illustrationen
    Series Statement: CRREL Report 82-39
    Language: English
    Note: CONTENTS Abstract Preface Introduction Objectives Analytical techniques Radio echo profiling Core drilling Results and discussion Brine infiltration survey Brine layer steps Brine infiltration characteristics Brine infiltration mechanisms at inland boundary Confirmation of brine depths by drilling Density and temperature profiles Ice shelf freeboard Brine upwelling Brine chemistry Conclusions Literature cited
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  • 5
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    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-82/38
    In: CRREL Report, 82-38
    Description / Table of Contents: Extreme cold causes heavy buildup of frost, ice and condensation on many windows. It also increases the incentive for improving the airtightness of windows against heat loss. Our study shows that tightening specifications for Alaskan windows to permit only 30% of the air leakage allowed by current American airtightness standards is economically attractive. We also recommend triple glazing in much of Alaska to avoid window icing in homes and barracks. We base our conclusions on a two-year field study of Alaskan military bases that included recording humidity and temperature data, observing moisture accumulation on windows and measuring airtightness with a fan pressurization device.
    Type of Medium: Series available for loan
    Pages: v, 26 Seiten , Illustrationen
    Series Statement: CRREL Report 82-38
    Language: English
    Note: Contents Abstract Preface Nomenclature Introduction Previous work in cold weather window performance Investigation Data acquisition and analysis Modeling the window thermal regime Moisture and ice observations Airtightness testing and analysis Annual heat loss from air leakage Results and conclusions Moisture on windows Airtightness Airtightness economics Recommendations for windows in extreme cold Airtightness Multiple glazing Literature cited Appendix A: Moisture levels and airtightness Appendix B: Dewpoint data Appendix C: Sample observations of icing
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  • 6
    Call number: ZSP-201-82/37
    In: CRREL Report, 82-37
    Description / Table of Contents: This report presents a Landsat-derived land cover map of the northwest portion of the Arctic National Wildlife Refuge, Alaska. The report is divided into two parts. The first is devoted to the land cover map with detailed descriptions of the mapping methods and legend. The second part is a description of the study area. The classification system used for the maps is an improvement over existing methods of describing tundra vegetation. It is a comprehensive method of nomenclature that consistently applies the same criteria for all vegetation units. It is applicable for large- and small-scale mapping and is suitable for describing vegetation complexes, which are common in the patterned-ground terrain of the Alaskan Arctic. The system is applicable to Landsat-derived land cover classifications. The description of the study area focuses on five primary terrain types: flat thaw-lake plains, hilly coastal plains, foothills, mountainous terrain, and river flood plains. Topography, landforms, soils and vegetation are described for each terrain type. The report also contains area summaries for the Landsat-derived map categories. The area summaries are generated for the five terrain types and for the 89 townships within the study areas. Two land cover maps at 1:250,000 are included.
    Type of Medium: Series available for loan
    Pages: 68 Seiten , Illustrationen, 2 Karten
    Series Statement: CRREL Report 82-37
    Language: English
    Note: CONTENTS Abstract Preface Foreword Introduction A land cover map of the ANWR study area Legend development Mapping method Results Discussion Description of the ANWR study area General description Description of specific terrain types Conclusions Literature cited Appendix A: Descriptions of Landsat land cover categories for ANWR Appendix B: Area summaries Appendix C: Aproximate equivalent units in several systems of land cover, wetland and vegetation classifications used in northern Alaska Appendix D: Soil taxonomy Appendix E: Summary of principal Landsat land cover categories within the terrain types of the ANWR study area
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  • 7
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    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-87/19
    In: CRREL Report, 87-19
    Description / Table of Contents: The approximate heat balance integral method (HBIM) is extended to the case of a medium with variable properties such as snow. The case of linear variation of thermal conductivity was investigated. An alternative heat balance integral method (AHBIM) was developed. Both constant surface temperature and surface heat flux were considered. A comparison was made of the temperature distribution from the HBIM, AHBIM and an analytical method for the case of constant surface temperature. In general, results agree quite well with the analytical method for small values of dimensionless time τ, but the difference becomes more pronounced as τ increases. It was found that the AHBIM with a quadratic temperature profile gave a somewhat better result, especially when the value of the dimensionless distance η is small. For a specific property function of E(η) = eη, closed form solutions were obtained. The results, when compared with those from HBIM, AHBIM and the analytical method were found to agree exceptionally well with the analytical method, especially for large values of τ.
    Type of Medium: Series available for loan
    Pages: iv, 26 Seiten , Illustrationen
    Series Statement: CRREL Report 87-19
    Language: English
    Note: CONTENTS Abstract Preface Nomenclature Introduction Mathematical analysis Constant surface temperature Constant surface heat flux Comparison with exact solution Alternative method Conclusions and comments Literature cited Appendix A: Derivation of equation 25 Appendix B: Derivations of equations 37 and 40 Appendix C: Derivation of equations 37a and 40
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  • 8
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    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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  • 9
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    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-87/21
    In: CRREL Report, 87-21
    Description / Table of Contents: The author measured time series of longitudinal (u) and vertical (w) velocity and temperature (t) and humidity (q) fluctuations with fast-responding sensors in the near-neutrally stable surface layer over a snow-covered field. These series yielded individual spectra and u-w, w-t, w-q and t-q cospectra, phase spectra and coherence spectra for nondimensional frequencies (fz/U) from roughly 0.001 to 10. With the exception of the u-w cospectra, all the spectra and cospectra displayed the expected dependence on frequency in an inertial or inertial-convective subrange. All, however, contained significantly more energy at low frequency than the Kansas neutral-stability spectra and cospectra. This excess low-frequency energy and the erratic behavior of the u-w cospectra imply that forested hills bordering the site on two sides were producing disturbances in the flow field at scales roughly equal to the height of the hills, 100 m. The phase and coherence spectra suggest that internal gravity waves were also frequently present, since the atmospheric boundary layer generally had slightly stable stratification. Consequently, at this complex site, turbulence alone determines the spectra and cospectra at high frequency; at low frequency the spectra and cospectra reflect a combination of topographically generated turbulence and internal waves. From the measured temperature and humidity spectra and the t-q cospectra, the author computed refractive index spectra for light of 0.55-micrometer and millimeter wavelengths. The refractive index spectra had shapes like the other scalar spectra: excess energy at low frequency and an inertial-convective subrange at high frequency.
    Type of Medium: Series available for loan
    Pages: v, 50 Seiten , Illustrationen
    Series Statement: CRREL Report 87-21
    Language: English
    Note: CONTENTS Abstract Preface Introduction Measurements Spectra u and w velocity spectra Temperature and humidity spectra Inertial-dissipation estimates Cospectra u-w cospectra w-t and w-q cospectra t-q cospectra Refractive index spectra Conclusions Literature cited
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  • 10
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    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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  • 11
    Call number: ZSP-201-87/2
    In: CRREL Report, 87-2
    Description / Table of Contents: This is the third in a series of four reports on the laboratory and field testing of a number of road and airfield subgrades, covering the laboratory repeated-load triaxial testing of five soils in the frozen and thawed states and analysis of the resulting resilient modulus measurements. The laboratory testing procedures allow simulation of the gradual increase in stiffnessfound in frost-susceptible soils after thawing. The resilient modulus is expressed in a nonlinear model in terms of the applied stresses, the soil moisture tension level (for unfrozen soil), the unfrozen water content (for frozen soil) and the dry density. The resilient modulus is about 10 GPa for the frozen material at temperatures in the range of -5° to -8° C. The decrease in modulus with increasing temperature was well-modeled in terms of the unfrozen water content. Upon thaw, the modulus dropped to about 100 MPa and generally increased with increasing confining stress and decreased with increasing principal stress ratio. The modulus also increased with the soil moisture tension level. The resilient Poisson's ratio did not appear to be a systematic function of any of the test variables.
    Type of Medium: Series available for loan
    Pages: iii, 36 Seiten , Illustrationen
    Series Statement: CRREL Report 87-2
    Language: English
    Note: CONTENTS Abstract Preface Introduction Test sections and materials Specimen preparation Test soils Asphalt concrete Laboratory testing Soil testing Waveforms of applied stress Asphalt concrete Data reduction and analysis Soil Asphalt concrete Results and discussion General Resilient modulus Summary Conclusions Literature cited Appendix A: Soil moisture tension versus water content for several test soils Appendix B: Tabulated results for all tests on frozen and thawed soils
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  • 12
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    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    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.
    Type of Medium: Series available for loan
    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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  • 13
    Call number: ZSP-201-82/19
    In: CRREL Report, 82-19
    Description / Table of Contents: Under proper design and management, a forest ecosystem in the central United States should renovate municipal wastewater as long or longer than conventional agricultural systems, especially when design limitations are hydraulic loading rate, heavy metals, P and N. Forest systems require smaller buffer zones than agricultural systems and lower sprinkler pressures. Immature forests are better wastewater renovators than mature forests.
    Type of Medium: Series available for loan
    Pages: iv, 22 Seiten , Illustrationen
    Series Statement: CRREL Report 82-19
    Language: English
    Note: CONTENTS Abstract Preface Introduction Forest systems design Pretreatment Distribution systems Public health considerations Buffer zone requirements Toxic effects Public access Hydraulic loading Nutrient uptake and loading Introduction Nitrogen Phosphorus Trace metals Design considerations Hydraulic loading rates Nitrogen loading rates Forest management options Reforestation Existing forest ecosystems Short term rotation plantations Potential long term effects on forest ecosystems Longevity of forest systems Consequences of overloading Soil chemical, physical and hydrologic properties Productivity Summary Literature cited
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  • 14
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    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
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    Call number: ZSP-201-82/18
    In: CRREL Report, 82-18
    Description / Table of Contents: Snow and ice control on highways has come to rely heavily on the use of sodium chloride to maintain a trafficable surface for unimpeded movement. Empirical approaches have led to a wide range of application rates, some clearly excessive, but justified on the ground of safety and expediency. The combination of environmental degradation from the huge quantities of salt entering the environment, along with the increased cost of salt itself and the cost of its application have spurred the search for more precise knowledge of the proper amount of salt to apply to a pavement, considering a range of environmental, traffic and chemical parameters. Since controlled tests in the field are extremely difficult to make, a circular test track of three test pavements, dense-graded asphaltic concrete (DGA), open-graded asphaltic concrete (DGA) and portland cement concrete (PCC), was constructed in a coldroom. Natural snow and ice were applied to the pavements and an instrumented slipping wheel was driven over the surfaces to generate frictional forces. These forces were measured and then used to evaluate the response to salt application with time for three test temperatures. OGA had the lowest friction values at a temperature near the freezing point, but higher initial values or more rapidly increasing values than DGA and PCC following salt application at the two lower temperatures. Optimum application rate of salt on PCC and DGA lies between 100 and 300 lb/lane mile (LM), and a higher rate resulted in slight or no improvement in friction. DGA showed anomalous results: lower friction for 300 Ib/LM and higher friction for both 100 and 500 Ib/LM.
    Type of Medium: Series available for loan
    Pages: vi, 55 Seiten , Illustrationen
    Series Statement: CRREL Report 82-18
    Language: English
    Note: CONTENTS Abstract Preface Introduction Objectives Background Approach Influencing factors Field factors Laboratory Laboratory trafficking tests Force measurement and coefficient of friction Test tire slip Surface friction gauge Test procedure British portable tester Experimental results Conclusions Recommendations Literature cited Appendix A. Test pavements Appendix B. Pennsylvania State University field study Appendix C. Rochester Institute of Technology field study
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  • 15
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    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
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    Call number: ZSP-201-82/17
    In: CRREL Report, 82-17
    Description / Table of Contents: Seismic P and SH wave refraction experiments at the NATO RSG-11 test site in Munster Nord, Federal Republic of Germany, reveal the presence of a nearly horizontal, three-layer velocity structure. The upper layer, composed of un­consolidated glacial till, is 1 m thick and has P (compressional) and SH (shear-horizontal) wave velocities of 240 and 165 m s-1. The second layer, made up of similar, more compacted material, is 9.5 m thick, with a P wave velocity of 470 m s-1 and an SH wave velocity of 275 m s-1. The third layer, interpreted as the groundwater table, is located at a depth of 10.5 m and has a P wave velocity of 1590 m s-1. The SH wave velocity of this layer is controlled by the matrix material and is the same as that of the second layer. A single, unreversed observation indicated a fourth layer at a depth of about 20 m, but the existence of this layer remains unconfirmed. The observed fundamental mode Love wave dispersion is in agreement with the theoretical dispersion predicted by the refraction velocities. Computed partial derivatives of phase velocity with respect to shear wave velocity show, for the frequencies observed, that the dispersion confirms the thicknesses and velocities of the two upper layers and is not affected by the deeper structure.
    Type of Medium: Series available for loan
    Pages: iv, 33 Seiten , Illustrationen
    Series Statement: CRREL Report 82-17
    Language: English
    Note: CONTENTS Abstract Preface Introduction Refraction experiments Procedure Equipment Results P waves Low velocity zone SH waves Surface wave experiments Summary and discussion Literature cited Appendix A: P wave refraction data Appendix B: SH wave refraction data. Appendix C: Surface wave dispersion calculations
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  • 16
    Call number: ZSP-201-82/15
    In: CRREL Report, 82-15
    Description / Table of Contents: An experiment is described that demonstrates the balance between the ice and the unfrozen water in a frozen soil as water is removed. Nuclear magnetic resonance (NMR) is used to monitor the unfrozen water content as the soil is dehydrated by a molecular sieve material. Our results show that the unfrozen water content of a Morin clay soil remains constant until the total water content has been reduced to the point where no ice remains in the system. Once the ice is depleted, the unfrozen water content determined by NMR corresponds to the total water content of the soil determined by the weight of water removed by the molecular sieve material. Thus the validity of utilizing NMR in determining unfrozen water contents vs temperature is established.
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    Pages: 8 Seiten , Illustrationen
    Series Statement: CRREL Report 82-15
    Language: English
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  • 17
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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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  • 18
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    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
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    Call number: ZSP-201-82/10
    In: CRREL Report, 82-10
    Description / Table of Contents: Dielectric measurements have been performed on silt and sand samples from permafrost areas using Time Domain Reflectometry. The sample temperatures were varied from +25 °C to -25 °C, and volumetric water content was varied between oven-dry and 0.55 gH2O/cm3. The data were processed for frequencies between 0.1 and 5.0 GHz. The results show a constant K' and a low K' for frequencies up to 1 GHz. A frequency dependence seen on the data above 2 GHz is probably the result of unfrozen, adsorbed water. At moisture levels near saturation at all temperatures, these soils have excellent propagation characteristics for ground-probing radar operating below 0.3 GHz. Massive ice should be easily detectable in permafrost within a few degrees of 0 °C.
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    Pages: 7 Seiten , Illustrationen
    Series Statement: CRREL Report 82-10
    Language: English
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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-201-82/11
    In: CRREL Report, 82-11
    Description / Table of Contents: The purpose of this investigation was to provide data to be used in evaluating the effects of winter navigation on pro­cesses that cause bank erosion. The specific objectives were to document bank conditions and erosion sites along the rivers, to monitor and compare the amounts of winter and summer bank recession and change, and to estimate the amount of recession that occurred prior to winter navigation. Shoreline conditions and bank recession were documented during field surveys each spring and fall. Bank changes were evaluated by comparison to observations from a previous survey. Aerial photointerpretation was done to estimate the amount of bank recession that occurred prior to winter navigation. Three hundred forty-five miles of river shoreline were surveyed. Banks were eroding along 21.5 miles (6.2%). The common types of bank failures were soil falls (sloughing) and block sliding and slumping. The erosion along approxi­mately 15 miles (70%) of the 21.5 miles was occurring along reaches not bordering winter navigation channels.
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    Pages: v, 75 Seiten , Illustrationen
    Series Statement: CRREL Report 82-11
    Language: English
    Note: CONTENTS Abstract Preface Introduction Previous investigations Approach Shoreline conditions Bank changes Bank recession before winter navigation St. Marys River Bank changes Bank recession before winter navigation St. Clair River Bank changes Bank recession before winter navigation Detroit River Bank changes Bank recession before winter navigation St. Lawrence River Bank changes Historical bank recession Summary and conclusions Literature cited Appendix A: St. Marys River Appendix B: St. Clair River Appendix C: Detroit River Appendix D: St. Lawrence River
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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-201-82/7
    In: CRREL Report, 82-7
    In: Charged dislocation in ice, II.
    Description / Table of Contents: The contribution of electrically charged dislocation motion to dielectric relaxation was studied theoretically. Experimentally obtained data on charge density, dislocation density, and segment length and distribution described in Part I of this series were used to calculate dielectric relaxation spectra. The results indicate that the charged dislocation process can produce the observed audio frequency dielectric relaxation as well as the distribution of spectra.
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    Pages: iii, 15 Seiten , Illustrationen
    Series Statement: CRREL Report 82-7
    Language: English
    Note: CONTENTS Abstract Preface Introduction Theoretical development of dielectric relaxation due to charged dislocations Numerical calculations for distributed segment length Discussion Conclusions Literature cited Appendix A. Mosotti type catastrophe by charged dislocation processes
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  • 21
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    Call number: ZSP-201-82/8
    In: CRREL Report, 82-8
    Description / Table of Contents: A detailed analysis of methods for calculating the thermal conductivity of soils is presented, and trends in the predic­tions of these methods are compared. The influence of changes in the moisture content on the calculated thermal con­ductivity of a soil (at constant dry density) is shown, as is the sensitivity of this calculated value to changes in dry den­sity or in the soil solids’ thermal conductivity. The methods are evaluated to determine the extent of agreement of their predictions with measured values obtained on soils of known composition and properties. The deviations of the predicted values are determined for soils that are unfrozen or frozen, coarse or fine, unsaturated, saturated or dry. The applicability of each of the methods under various conditions is determined and recommendations are made as to the best method for each condition.
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    Pages: vi, 90 Seiten , Illustrationen
    Series Statement: CRREL Report 82-8
    Language: English
    Note: CONTENTS Abstract Preface Nomenclature Introduction Analysis of methods for calculating thermal conductivity Introduction Influence of moisture content on thermal conductivity Influence of dry density on thermal conductivity Influence of soil solids’ thermal conductivity Comparison of the various methods Evaluation of methods for calculating thermal conductivity Soils data used for evaluation Computer program Applicability of the methods Discussion and conclusions Applicability to unfrozen soils Applicability to frozen soils Applicability to saturated soils Effect of soil mineral composition Applicability to dry soils Summary of applicability of methods Literature cited Appendix A: Properties of some test soils Appendix B: Comparison of thermal conductivity values computed by the various methods and of their deviations from the values measured
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  • 22
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    Call number: ZSP-201-82/9
    In: CRREL Report, 82-9
    Description / Table of Contents: This study deals with the distribution of forces along the converging boundaries of the Port Huron, Michigan, region where unconsolidated ice in Lake Huron is held against wind and water stresses. An experimental basin was built to induce uniform shear stress on the model ice cover by flowing water beneath the ice. The boundary segments, which held the ice cover in the region, were instrumented to measure force in the normal and tangential directions. The distribution of normal forces along the boundary was compared with as distribution derived by using a theoretical model. An ice control structure (ICS) was installed in the basin and experiments were conducted to measure the forces on the ICS and the ice release through the opening in the ICS during simulated ship passages. The experimental results are presented in a nondimensional form. In addition, the force per unit length on the ICS and the area of ice released through its opening were estimated for the expected wind conditions at the Port Huron site.
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    Pages: v, 27 Seiten , Illustrationen
    Series Statement: CRREL Report 82-9
    Language: English
    Note: CONTENTS Abstract Preface List of symbols Introduction Theoretical models Case 1 Case 2 Case 3 Experimental program Experimental facility Scaling factors Experimental results Analysis of wind data for lower Lake Huron Summary and conclusions Release of ice through the opening of an ICS Ice forces on the ice control structure Ice forces on ice control structure from a large unconsolidated ice cover Literature cited Appendix A. Equation for the stress resultants and velocities of the ice cover Appendix B. Monthly summary of wind data at Port Huron
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  • 23
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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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  • 24
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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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  • 25
    Call number: ZSP-201-87/14
    In: CRREL Report, 87-14
    Description / Table of Contents: During February and March 1980 the physical properties of Weddell Sea pack ice were investigated via core drilling of 66 floes located along the transect of 600 nautical miles from 64°S to 74°S latitude at roughly 40°W longitude. These studies revealed widespread frazil ice in amounts not known to exist in Arctic sea ice of comparable age and thickness. It is estimated from structure studies of 62 of the 66 floes that 54% of the total ice production of the Weddell Sea is generated as frazil. The disposition and exceptional thickness of the frazil show that mechanisms other than surface turbulence effects are involved and imply that the circulation and structure of the water in the upper levels of the Weddell Sea are significantly different from those in the Arctic basin. Salinities of both first-year and multi-year floes are notably higher than those of their Arctic counterparts because summer surface melting is rare or absent in the Weddell Sea; in the Arctic, downward percolating meltwater flushes through the ice and lowers its salinity. Fluorescence was evaluated as a means of revealing biological activity in Weddell Sea pack ice. It proved useful as an index of combined living and dead material in the ice, but measurements failed to establish any consistent relationship between fluorescence and salinity as suggested be earlier work in the Weddell Sea.
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    Pages: iv, 80 Seiten , Illustrationen
    Series Statement: CRREL Report 87-14
    Language: English
    Note: CONTENTS Preface Introduction Sea ice structure and classification Logistics and field operations Analytical techniques Crystalline structure Fluorescence Results Salinity Crystalline structure Fluorescence Description of selected floes Conclusions Literature cited Appendix A: Floe descriptions
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  • 26
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    Call number: ZSP-201-87/15
    In: CRREL Report, 87-15
    Description / Table of Contents: Constant strain-rate tension tests were conducted on remolded saturated frozen Fairbanks silt at various temperatures, strain rates, and densities. It was found that the critical strain rate of the ductile-brittle transition is not temperature-dependent at temperatures down to -5°C, but varies with density. The peak tensile strength decreases considerable with decreasing strain rate for ductile failure, but it decreases slightly with increasing strain rate for brittle fracture. The failure strain remains almost constant at temperatures lower than about -2°C, but it varies with density and strain rate at -5°C. The initial tangent modulus is independent of strain rate and increases with decreasing temperature and density.
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    Pages: v, 29 Seiten , Illustrationen
    Series Statement: CRREL Report 87-15
    Language: English
    Note: CONTENTS Abstract Preface Nomenclature Introduction Testing Material Specimen preparation Testing procedure and apparatus Results Discussion Peak tensile strength, σm Failure tensile strain, ϵf Initial tangent modulus and 50% peak strength modulus Discussion of test techniques Conclusions Literature cited Appendix A: Physical properties of Fairbanks silt specimens Appendix B: Unfrozen water content data of Fairbanks silt with three typical water contents
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  • 27
    Call number: ZSP-201-87/17
    In: CRREL Report, 87-17
    Description / Table of Contents: The ability to map frazil ice deposits and water channels beneath an ice-covered river in central Alaska using the magnetic induction conductivity (MI) technique has been assessed. The study was performed during the first week of March of 1986 on the Tanana River near Fairbanks and employed a commercially available instrument operating at a fixed frequency with a fixed antenna (coil) spacing and orientation. Comparisons of the MI data with theoretical models based upon physical data measured along three cross sections of the river demonstrate the sensitivity of the MI technique to frazil ice deposits. The conductivity generally derived for the frazil ice deposits encountered is very low (approx. .00063 s/m) when compared with the measured value for water (approx. 0.011 S/m), and is similar to the calculated values for gravel and sandy gravel bed sediments. In all three cross sections, maxima in the apparent conductivity profiles correlated with frazil ice deposits. Difficulties, possibly due to adverse effects of cold weather upon instrument calibration, affected the quantitative performance of the instrument on one cross section, although the interpretation of the data (locations of open channels vs frazil deposits) was qualitatively unaffected.
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    Pages: iii, 17 Seiten , Illustrationen
    Series Statement: CRREL Report 87-17
    Language: English
    Note: CONTENTS Abstract Preface Introduction Magnetic induction conductivity method Site description and survey methods Cross section field data and modeling results X6 X3A X4 Conclusions and recommendations Literature cited Appendix A: Discussion of errors Appendix B: Modeling data
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  • 28
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    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.
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    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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  • 29
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    Call number: ZSP-201-82/13
    In: CRREL Report, 82-13
    Description / Table of Contents: Frost heave is analyzed for the common case in which some ice penetrates the soil. In this situation, heave is due to the accumulation of soil-free ice just within the frozen zone, behind a frozen fringe of finite thickness. Heat and mass transport within and across that fringe are crucial processes in the dynamics of heave. This analysis concentrates on activity within the fringe, also connecting that activity to heat and mass flows in the more frozen and unfrozen zones. Each component in a set of governing differential equations is developed from rational physics and thermodynamics, using previous experimental work. It is assumed that the soil ice grows through interconnected interstices; hence it constitutes and can move as a rigid body. When the assumption is translated into mathematical terms, it completes the governing equations. The model resulting from these considerations is a one-dimensional finite element computer program that solves the equations for arbitrary initial and boundary conditions. The model is used to simulate the heave history of a hypothetical soil column frozen unidirectionally and subjected to a surcharge. The results are gratifying in that they predict qualitatively the characteristics of numerous laboratory observations. Some questions about the completeness of the theory remain, and strict verification of the model awaits further experimentation and better parameter identification.
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    Pages: iii, 11 Seiten , Illustrationen
    Series Statement: CRREL Report 82-13
    Language: English
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  • 30
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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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  • 31
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    Call number: ZSP-201-82/3
    In: CRREL Report, 82-3
    Description / Table of Contents: The conditions that lead to initial breakup of a solid ice on a river due to rapid water level variations are analyzed. The analysis is based on the theory of beams on an elastic foundation. First cracking is assumed to occur when the bending moment induced in the ice cover by the wave exceeds the flexural strength of the ice cover.
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    Pages: iv, 17 Seiten , Illustrationen
    Series Statement: CRREL Report 82-3
    Language: English
    Note: CONTENTS Abstract Preface Symbols Introduction Purpose of the study Stating the problem Fracturing of the ice cover due to the passage of surge waves Basic assumptions Derivation of the bending moments Determination of the wave characteristics Deflection of the ice Discussion and field observations Summary Literature cited
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  • 32
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    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
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    Call number: ZSP-201-82/6
    In: CRREL Report, 82-6
    Description / Table of Contents: The interpretation of continuous radar profiles requires an alternative geophysical means of obtaining ground dielectric information. Ground dielectric properties were measured using wide-angle reflection and refraction (WARR) soundings with a ground-probing radar set that transmits pulses f a few nanoseconds duration. The investigations, carried out over sandy gravel in interior Alaska, provided dielectric data to about a 5-m depth. The WARR soundings were displayed as individual traces allowing interference between separate events and dispersion to be observed, and the soundings were compared with continuous radar and resistivity profiles conducted concurrently to extract the maximum amount of dielectric information. The dielectric constants, derived mainly from the direct ground waves propagating along the surface, ranged from 2.9 to 7.4. Dielectric values interpreted for one site predicted the possibility of a refracted event which may have occurred during one of the soundings.
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    Pages: iii, 11 Seiten , Illustrationen
    Series Statement: CRREL Report 82-6
    Language: English
    Note: CONTENTS Abstract Preface Introduction Theory of ground wave propagation from a horizontal electric dipole Equipment and methods Results Site 1 Site 2 Site 3 Summary and concluding remarks Literature cited
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  • 33
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    Call number: ZSP-201-82/5
    In: CRREL Report, 82-5
    Description / Table of Contents: The problem of simultaneous heat and mass transfer in a homogeneous snow layer, with one side kept at its initial temperature and the other side with a step temperature increase, was solved for the case of constant through-flow conditions. An experimentally determined effective thermal conductivity function, i.e. Ke = 0.0014 + 0.58 G (where G is dry mass flow rate of air in g/sq cm-s), was employed in the solution. The computed nondimensional temperature distribution agreed quite well with experimental data taken under pseudo-steady state conditions with the exception of the temperature for the lowest flow rate used in the experiment. The pronounced nonlinearity of the temperature distribution was found to be a strong function of the flow rate. For sinusoidal variation of atmospheric pressure, the responding flow in the snow medium was also found to be sinusoidal. In conjunction with the diurnal temperature change, this variation facilitated the process of repeated sublimation and condensation in alternate directions and thereby produced a surface layer of approximately constant snow density.
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    Pages: v, 10 Seiten , Illustrationen
    Series Statement: CRREL Report 82-5
    Language: English
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  • 34
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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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  • 35
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    Call number: ZSP-201-82/43
    In: CRREL Report, 82-43
    Description / Table of Contents: The radar signatures of ice wedges and wedge-like structures have been investigated for a variety of soil conditions. The radar used for this study emitted short sinusoidal pulses of about 10-ns duration with an approximate center frequency of 150 MHz. Most of the ice wedges existed at depths of about 1 m in a variety of silty and sandy soils with both frozen and thawed active layers. The position of the wedges was usually identified from corresponding surface features. An artificial ice wedge in coarse-grained alluvium was also profiled as well as wedge-like structures of fine silt in a coarse-grained glacial outwash. All wedges and wedge-like structures produced a hyperbolic reflection profile except when an active layer of thawed, saturated silt was present which eliminated returns from the wedges. The peaks of the hyper-bolas were sometimes masked by reflections from the permafrost table or other material interfaces, and multiple hyperbolas occurred at some sites. The dielectric constant of the host medium was often calculated from the linear portions of the hyperbolas and the results were verified by laboratory time domain reflectometry measurements per-formed on field samples. In some cases, hyperbolic profiles originated at several meters depth suggesting that deep ice wedges could be detected in areas of cold permafrost.
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    Pages: iv, 19 Seiten , Illustrationen
    Series Statement: CRREL Report 82-43
    Language: English
    Note: CONTENTS Abstract Preface Introduction Background Objectives and procedures Equipment used Radar TDR Definitions Massive ice Results Artificial wedge: Norwich, Vermont Ice wedges in sand: Fish Creek, Alaska Ice wedges: Prudhoe Bay, Alaska Ice wedges under thawed fine-grained soils: North Slope, Alaska Wedge-like soil structures: Ft. Greely, Alaska TDR measurements Summary and concluding remarks Literature cited Appendix A: Brief discussion of dispersion
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  • 36
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    Call number: ZSP-201-82/24
    In: CRREL Report, 82-24
    Description / Table of Contents: Velocity data derived from petroleum industry seismic records from Harrison Bay show that high-velocity material ( or = 2 km/s) interpreted to be ice-bonded permafrost is common. In the eastern part of the bay, the depth to high velocity material increases and velocity decreases in an orderly manner with increasing distance from shore until the layer is no longer apparent. The western part of the bay is less orderly, possibly reflecting a different geological and thermal history. This western part may be an inundated section of the low coastal plain characterized by the region north of Teshekpuk Lake, and could have contained deep thaw lakes, creating low velocity zones. Along some seismic lines, the high-velocity material extends approximately 25 km offshore. Two anomalies have been found which could be associated with rapidly degrading permafrost. One is strong attenuation, which was interpreted as an indication of gas in the shallow deposits. The other is the presence of considerable seismic noise, including identifiable small seismic events. The origin of this noise has not been positively established, and it is proposed that it may indicate that some movement is occurring in the sediments due to thaw.
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    Pages: 65 Seiten , Illustrationen
    Series Statement: CRREL Report 82-24
    Language: English
    Note: CONTENTS Abstract Preface Introduction Methods Reading records Refractions Reflections Rayleigh waves Spatial resolution Anomalies Results and discussion Seismic velocity distribution Attenuation Low-level natural seismicity Summary Literature cited Appendix A: Error estimates Appendix B: Velocity profiles Appendix C: Seismic cross sections
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  • 37
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    Call number: ZSP-201-82/23
    In: CRREL Report, 82-23
    Description / Table of Contents: A direct filtration, water treatment pilot plant was operated on the Kenai River at Soldotna, Alaska, during the summer of 1980. The purpose of the pilot plant operations was to determine the feasibility of the direct filtration process for removal of glacial silt. The major criterion used to determine feasibility was production of water containing less than 1.0 NTU of turbidity. For the range of raw water turbidities encountered (22-34 NTU), the pilot plant testing indicated that direct filtration was feasible and could be considered as an alternative to conventional waiter treatment plants containing sedimentation tanks.
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    Pages: 26 Seiten , Illustrationen
    Series Statement: CRREL Report 82-23
    Language: English
    Note: CONTENTS Abstract Preface Conversion factors: U.S. customary to metric Introduction Glacial characteristics Water treatment Materials and methods Experimental design Pilot plant intake Hydrocyclone Chemical addition system Flocculation system Filtration system Pilot plant operations Coagulant chemical preparations Flow measurement Sampling Results and discussion Kenai River w ater quality Evaluation of pilot plant testing Performance of pilot plant elements Physical and chem ical variables Conclusions Recommendations Literature cited
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  • 38
    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.
    Type of Medium: Series available for loan
    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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  • 39
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    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
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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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  • 40
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    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    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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  • 41
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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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  • 42
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    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
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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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  • 43
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    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
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    Call number: ZSP-201-87/4
    In: CRREL Report, 87-4
    Description / Table of Contents: In this report we present results of measurements of the crystalline structure and salinity characteristics of sea ice in Hebron Fiord and vicinity, Labrador. Structurally, the fiord ice was entirely first year and composed predominantly of congelation, columnar-type crystals. At most of the sampling sites the ice exhibited moderately to strongly aligned c-axes consistent with the inferred direction of near surface currents in the fiord. Generally diminished values of bulk salinity at five separate locations reflect the warm ice conditions encountered at the time of sampling (late May) and the effect of meltwater flushing in promoting loss of brine, vertically, from the ice sheet. Observations outside Hebron Fiord indicated the presence of only minor amounts of multiyear ice during the latter part of May.
    Type of Medium: Series available for loan
    Pages: iii, 25 Seiten , Illustrationen
    Series Statement: CRREL Report 87-4
    Language: English
    Note: Contents: Abstract Preface Introduction Sampling procedure Analytical techniques Salinities Crystal structure Results Salinity Crystal structure Brine layer spacing Incidental temperatures Conclusions Literature cited Appendix A: Vertical and horizontal thin section photographs of sea ice from various sites
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  • 44
    Call number: ZSP-201-87/3
    In: CRREL Report, 87-3
    Description / Table of Contents: This report describes the structural analysis of multi-year sea ice samples that were tested in the first 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 also considered, based on the extensive field sampling that was done in the program
    Type of Medium: Series available for loan
    Pages: iii, 40 Seiten , Illustrationen
    Series Statement: CRREL Report 87-3
    Language: English
    Note: CONTENTS Abstract Preface Introduction Sample analysis Continuous multi-year ridge core Tested multi-year ridge ice samples Tested multi-year floe ice samples Ice description Uniaxial constant-strain-rate compression tests Uniaxial constant-load compression tests Uniaxial constant-strain-rate tension tests Triaxial constant-strain-rate compression test Conclusions Literature cited Appendix A: Multi-year ridge sample data Appendix B: Multi-year floe sample data
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  • 45
    Call number: ZSP-201-87/6
    In: CRREL Report, 87-6
    Description / Table of Contents: Two-phase dielectric mixing model results are presented showing the electromagnetic properties of sea ice versus depth. The modeled data are compared with field measurements and show comparable results. It is also shown how the model data can be used in support of impulse radar and airborne electromagnetic(AEM) remote sensing of sea ice. Examples of the remote measurement of sea ice thickness using impulse radar operating in the 80- to 300-MHz frequency band and low-frequency (500 to 30,000 Hz) sounding techniques are presented and discussed. Keywords: Polar regions; Radar pulses.
    Type of Medium: Series available for loan
    Pages: vii, 55 Seiten , Illustrationen
    Series Statement: CRREL Report 87-6
    Language: English
    Note: Contents Abstract Preface Nomenclature Introduction Sea ice growth and structure Model sea ice Brine salinity Seawater and model brine conductivity Complex dielectric constant of brine Electromagnetic properties of model sea ice at 100 MHz Electromagnetic properties of model sea ice at 100 and 500 MHz and 1 and 5 GHz Example of impulse radar sea ice profiling results Example of frequency-domain electromagnetic sea ice thickness sounding Concluding remarks Literature cited
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  • 46
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    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
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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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  • 47
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    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
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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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  • 48
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    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
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    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.
    Type of Medium: Series available for loan
    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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  • 49
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    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
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    Call number: ZSP-201-82/1
    In: CRREL Report, 82-1
    Description / Table of Contents: On 27 March 1964 a major earthquake struck Southern Alaska. The city of Anchorage, which contained a large part of Alaska's population, suffered loss of life and destruction of property. The time of the day, the season, and ground conditions were such that loss of life and property was minimized. The frozen ground and the ice on fresh waster bodies responded to the earthquake shocks in a seldom-observable pattern, which was noted and recorded. Changes of sea level and slides into the sea were responsible for waterfront destruction. It is concluded that the main factor that limited structural damage was the frozen state of the ground.
    Type of Medium: Series available for loan
    Pages: iv, 26 Seiten , Illustrationen
    Series Statement: CRREL Report 82-1
    Language: English
    Note: CONTENTS Abstract Preface Abstract of events Earthquakes and frozen ground The response of freshwater ice sheets to earthquake shock The earthquake disturbance in glaciated mountains Disturbed wildlife Tidal waves Summary Literature cited
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  • 50
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    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
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    Call number: ZSP-201-82/4
    In: CRREL Report, 82-4
    Description / Table of Contents: Several proposed methods for treating the momentum flux between drifting sea ice and the underlying ocean are interpreted in terms of simple planetary-boundary-layer (PBL) turbulence theory. The classical two-layer approach, in which the solution for a thin surface layer is matched to an Ekman solution for the outer layer, is used to derive several forms of the drag law. These forms range from linear (where stress is proportional to relative speed), through quadratic (where stress is proportional to relative speed squared), to a Rossby-similarity law like that used to express frictional drag on geostrophic wind in the atmosphere. Only formulations which conform with Rossby-similarity scaling are consistent with free-drift data from the 1975 AIDJEX drift station experiment.
    Type of Medium: Series available for loan
    Pages: iv, 17 Seiten , Illustrationen
    Series Statement: CRREL Report 82-4
    Language: English
    Note: CONTENTS Abstract Preface Background Hierarchy of drag laws and simple models The momentum equation for the planetary boundary layer Linear eddy viscosity - the constant stress layer Two-layer eddy viscosity PBL scaling A dimensionless two-layer system A dimensionless two-layer system with modified stress Evaluating the drag laws Rossby similarity parameters and buoyancy effects Discussion Literature cited
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