ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
  • English  (375)
  • Romanian
  • 1
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-202-345
    In: Research report / Cold Regions Research and Engineering Laboratory, 345
    Description / Table of Contents: CONTENTS: Abstract. - Preface. - List of symbols. - Introduction. - Previous work. - Experimental design. - The radioisotope 22Na. - Description of apparatus. - Experimental procedure. - Correction of profiles. - Assumptions. - Decay correction. - Boundary correction. - Error analysis. - Results. - Salinity data. - Temperature data. - Growth velocity. - Discussion. - Brine and ice properties. - Brine salinity. - Brine density. - Brine volume. - Brine latent heat of freezing. - Brine viscosity, specific heat, and thermal conductivity. - Ice properties. - Theoretical brine expulsion model. - Continuity equations. - Thermal energy equation. - Simplified brine expulsion equations. - Brine expulsion in NaCl ice. - Results. - Discussion. - Gravity drainage in NaCl ice. - Application of results to natural sea ice. - Effective distribution coefficient. - Previous work. - Experimental procedure and results. - Conclusions. - Literature cited. - Appendix A: Profile correction data. - Appendix B: Program "correct" and sample output. - Appendix C: Tabulation of salinity data. - Appendix D: Tabulation of profile data. - Appendix E: Time-ice thickness equations (Runs 2 and 3). - Appendix F: Tabulation of distribution coefficient data.
    Description / Table of Contents: To obtain a better understanding of the desalination of natural sea ice, an experimental technique was developed to measure sequential salinity profiles of a growing sodium chloride ice sheet. Using radioactive 22Na as a tracer, it was possible to determine both the concentration and movement of the brine within the ice without destroying the sample. A detailed temperature and growth history of the ice was also maintained so that the variation of the salinity profiles could be properly interpreted. Since the experimental salinity profile represented a smoothed, rather than a true salinity distribution, a deconvolution method was devised to restore the true salinity profile. This was achieved without any significant loss of end points. In all respects, the salinity profiles are similar to those of natural sea ice. They have a characteristic C-shape, and clearly exhibit the effects of brine drainage. Not knowing the rates of brine expulsion or gravity drainage, the variation of the salinity profiles during the period of ice growth could be explained by either process. To determine the relative importance of the desalination mechanisms, a theoretical brine expulsion model was derived and compared to the experimental data. As input for the model, equations describing the variation of some properties of NaCl brine with temperature were derived. These included the brine salinity, viscosity, specific heat, thermal conductivity, and latent heat of freezing. The theoretical brine expulsion model was derived by performing mass and energy balances over a control volume of NaCl ice. A simplified form of the model, when compared to the experimental results, indicated that brine expulsion was only important during the first several hours of ice growth, and later became a minor desalination process relative to gravity drainage which continued to be the dominant mechanism for the remainder of the study period (up to 6 weeks). The rate of gravity drainage was found to be dependent on the brine volume and the temperature gradient of the ice. As either the brine volume or temperature gradient was increased, the rate of change of salinity due to gravity drainage increased. The equation commonly used to calculate the effective distribution coefficient (Weeks and Lofgren 1967) was modified and improved by taking brine drainage into account. An expression was also derived to give the distribution coefficient at very low growth velocities.
    Type of Medium: Series available for loan
    Pages: vii, 85 Seiten , Illustrationen
    Series Statement: Research report / Cold Regions Research and Engineering Laboratory 345
    Language: English
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 2
    Call number: ZSP-202-337
    In: Research report
    Description / Table of Contents: Contents: Introduction. - Surface ice observations. - Imagery interpretation. - Side-looking airborne radar. - Infrared. - Conclusions. - Literature cited.
    Description / Table of Contents: Ice conditions during mid-January 1974 in the Gulf of St. Lawrence and in the estuaty as far upstream as Rimouski are described utilitizing side-looking airborne radar, infrared and photographic imagery. The interpretations were verified by simultaneous surface observations on the ice by investigators operating from the CSS Dawson. The ice examined was undergoing rapid drift and deformation and showed a wide variety of thin ice (0-40 cm) features formed under the influence of strong winds and currents. These observations should serve as a guide in interpreting ice conditions in similar areas where ground truth data are not available.
    Type of Medium: Series available for loan
    Pages: 41 Seiten , Illustrationen
    Series Statement: Research report / Cold Regions Research and Engineering Laboratory, CRREL, US Army Material Command 337
    Language: English
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 3
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-202-339
    In: Research report
    Description / Table of Contents: CONTENTS: Abstract. - Preface. - Introduction. - Analytical procedures. - Thick section analysis. - Measurements of inclusion pressure. - Gas volume measurements. - Density and porosity measurements. - Results and discussion. - Sizes, shapes and distributions of bubbles. - Sizes, shapes and distributions of cavities. - Inclusion abundances. - Gas pressures in bubbles and cavities. - Total gas content. - Case for lattice diffusion. - Literature cited.
    Description / Table of Contents: Cores obtained to the bottom of the Antarctic Ice Sheet at Byrd Station were used to analyze the physical properties of air bubbles trapped in the ice. These bubbles originate as pockets of air in the upper layers of snow and approximately 10 ml of air/100 cm^3 of ice; i.e., 10% by volume is retained permanently when the snow transforms into ice. Parameters measured were the sizes, shapes, abundances, spatial distributions, gas volumes and pressures of bubbles, and their variations with depth in the ice sheet. Bubbles occur abundantly in the top 800 m of ice but then gradually disappear until they can no longer be detected optically below 1100 m. This disappearance is not accompanied by any significant loss of air from the ice and all available evidence indicates that the air actually diffuses into the ice in response to increasing overburden pressure. The possibility exists that the dissolved gases are retained in the form of a gas hydrate or clathrate which, because of release of confining pressures, begins to decompose soon after ice cores are pulled to the surface. This decomposition is accompanied by the growth of gas-filled bubble-like cavities, and as much as 40% of the dissolved air has exsolved already from some cores in the space of less than three years. Bubble pressure measurements show that 1) bubbles with pressures exceeding about 16 bars begin to relax back to this value soon after in situ pressures are relieved by drilling, 2) further slow decompression occurs with time, and 3) the rate of decompression is controlled to some extent by the intrinsic structural properties of the ice and its thermal and deformational history. Only small variations were observed in the entrapped air content of the ice cores; they probably reflect variations in the temperature and/or pressure of the air at the time of its entrapment, but the data are not sufficient to draw any firm conclusions regarding past variations in ice sheet thickness. Only ice from the bottom 4.83 m was found to lack any detectable trace of air. Since this absence of air coincided precisely with the first appearance of stratified moraine in the cores, it is concluded that this ice originated from the refreezing of air-depleted water produced under pressure melting conditions at the bottom of the ice sheet.
    Type of Medium: Series available for loan
    Pages: v, 18 Seiten , Illlustrationen
    Series Statement: Research report / Cold Regions Research and Engineering Laboratory, CRREL, US Army Material Command 339
    Language: English
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 4
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-202-313
    In: Research report
    Description / Table of Contents: CONTENTS: Preface. - Nomenclature. - Introduction. - Funicular regime. - Grain growth. - Grain contacts. - Densification. - Pendular regime. - Discussion and conclusions. - Literature cited. - Abstract.
    Description / Table of Contents: Grain growth, bond growth and densification of wet snow are described in terms of the distribution of equilibrium temperature in the snow matrix. At high water saturations the equilibrium temperature increases with grain size; hence, small particles melt away as large particles grow. Melting also occurs at the intergrain bonds, causing a low strength and rapid densification. At low saturations the equilibrium temperature is determined by the capillary pressure and the particle sizes have only a second order effect. Therefore, grain growth proceeds slowly and, even at large overburden pressures, no intergrain melting occurs. At low saturations the water "tension" acts through a finite area, thus large attractive forces exist between the grains, and the strength of the snow matrix is large.
    Type of Medium: Series available for loan
    Pages: v, 13 Seiten , Illustrationen
    Series Statement: Research report / Cold Regions Research and Engineering Laboratory, CRREL, US Army Material Command 313
    Language: English
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 5
    Call number: ZSP-202-315
    In: Research report
    Description / Table of Contents: CONTENTS: Preface. - Introduction. - Part 1:Mesoscale strain measurements on the Beaufort Sea pack ice. - Abstract. - Introduction. - Previous work. - Site location. - Results. - Correlation of synoptic aerial photography with measured strains. - Correlation of estimated wind stress and strain. - Conclusions. - Literature cited. - Part II: Structure of a multiyear pressure ridge. - Abstract. - Introduction. - Profiles. - Internal properties. - Largest ridge sail. - Conclusions. - Literature cited. - Part III: Top and bottom roughness of a multiyear ice floe. - Abstract. - Introduction. - Results. - Literature cited. - Part IV:Airphoto analysis of ice deformation in the Beaufort Sea Abstract. - Introduction. - Study area. - Method of analysis. - Ice deformations. - Net deformational changes. - Pressure ridge distribution. - Summary and conclusions. - Literature cited. - Part V: Data on morphological and physical characteristics of sea ice in the Beaufort Sea.
    Description / Table of Contents: Mesoscale strain measurements on the Beaufort Sea pack ice; Structure of a multiyear pressure ridge; Top and bottom roughness of a multiyear ice floe; Airphoto analysis of ice deformation in the Beaufort Sea; Data on morphological and physical characteristics of sea ice in the Beaufort Sea.
    Type of Medium: Series available for loan
    Pages: iii, 66 Seiten , Illustrationen
    Series Statement: Research report / Cold Regions Research and Engineering Laboratory, CRREL, US Army Material Command 315
    Language: English
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 6
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-202-312
    In: Research report
    Description / Table of Contents: CONTENTS: Preface. - Nomenclature. - Introduction. - Test specimen. - Equipment and procedure. - Test chamber. - Error of eccentricity. - Equipment. - Procedure. - Results. - Tensile strength. - Fracture. - Discussion. - Uniaxial tensile strength. - Brazil test. - Comparison with theory. - Conclusions. - Literature cited. - Appendix A. Test results. - Abstract.
    Description / Table of Contents: An investigation was conducted to determine the effect of a compressive stress on the tensile strength of bubbly polycrystalline ice. One hundred forty-five tests were made in an apparatus of novel design. A cylindrical dumbbell specimen was stressed in axial tension and radial and tangential compression by a hydraulic system which minimized bending stresses. Compression-tension ratios ranging from 0.21 to 10.14 were used for the tests. Tensile strength was found to decrease with an increase in the ratio. At the ratio of 3.155 the tensile strength is about one third the uniaxial value. The test results support the evidence that the Brazil test underestimates the tensile strength for ice. They also indicate that the Brazil test value for ice can be no greater than one third the uniaxial tensile strength. A comparison of the experimental results with a few prominent biaxial failure theories indicates a lower tensile strength than predicted by any theory. However, the best approximation to the results is the Coulomb-Mohr criterion.
    Type of Medium: Series available for loan
    Pages: iv, 21 Seiten , Illustrationen
    Series Statement: Research report / Cold Regions Research and Engineering Laboratory, CRREL, US Army Material Command 312
    Language: English
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 7
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-202-314
    In: Research report
    Description / Table of Contents: CONTENTS: Introduction. - Previous work. - Sea ice terrain model. - Traffic ability model. - Analytic calculation of DT/DSL. - Monte Carlo calculation. - Results of traffic ability computations. - Experimental traffic ability ratios using ridge overlays. - Regional variations in ridging intensity. - Additional traffic ability aspects of sea ice. - Shear zone and rubble fields. - Linear lead systems. - Conclusions. - Literature cited. - Appendix A. Distribution of the lateral extent of ridges. - Abstract.
    Description / Table of Contents: A sea ice terrain model, based upon previously tested height and spacing distributions for sea ice pressure ridging, is developed. Using this model, and additional information on pressure ridge extents, a trafficability model for vehicles traversing the pack ice is developed. Both analytic and Monte Carlo calculations of vehicle trafficability, measured in terms of the average ratio of the total distance traveled over a straight-line distance, are performed. The calculations include cul-de-sacs due to ridge intersections. The trafficability ratio is given as a function of ridge-height-clearance ability of the vehicle and of ridging parameters which may be obtained from laser profiles of the arctic pack ice. Results are in good agreement with simulated routes through sea ice terrain taken from aerial photo mosaics. Contour plots of ridging parameters taken from laser profilometry are also supplied. These plots, together with the trafficability model, supply mobility information for the whole of the western portion of the Arctic Basin.
    Type of Medium: Series available for loan
    Pages: iii, 21 Seiten , Illustrationen
    Series Statement: Research report / Cold Regions Research and Engineering Laboratory, CRREL, US Army Material Command 314
    Language: English
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 8
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-202-291
    In: Research report
    Description / Table of Contents: CONTENTS: Introduction. - Study lake. - Previous work at Post Pond. - Methods and procedures. - Results and discussion. - Summer stratification. - Autumnal mixing and thermocline disappearance. - Winter period of ice cover. - Spring circulation. - Summary and conclusions. - Literature cited. - Appendix A: Ice sample analysis. - Abstract.
    Description / Table of Contents: The temperature structure of Post Pond, a small (46.6 hectares), mid-latitude, dimictic lake in west-central New Hampshire, was studied during autumn,winter and spring of 1968-1969. The lake was instrumented over its maximum depth (11.7 m) with a string of 24 thermocouples which recorded hourly temperatures. Temperatures in 9 m of sediments underlying the lake were measured with a thermistor probe. Secondary and tertiary thermocline development in the epilimnion occurred during short warming periods in the early autumn. The autumn overturn lasted 25 days, whereas the spring overturn lasted only 4 days. The entire lake mixed isothermally in the autumn to 3.2°C. During the period of ice cover, the lower 5 m of water gained approximately 51.5 cal/cm^2, which was supplied by stored heat in the bottom sediments. A steady-state thermal gradient of 0.07°C/m was found for the deeper sediments underlying the lake during ice cover. Late winter cooling of bottom water under the ice cover may be the result of snowmelt in areas adjacent to the lake causing activation of groundwater influx. Melting of the clear ice portion of the ice cover was primarily the result of heat supplied to the lake from snowmelt water, and occurred on the underside of the ice sheet. Thermal instability of the water mass persisted for 9 days during peak snowmelt runoff; this can be partially explained by an increase in dissolved solids with depth.
    Type of Medium: Series available for loan
    Pages: 23 Seiten , Illustrationen
    Series Statement: Research report / Cold Regions Research and Engineering Laboratory, CRREL, US Army Material Command 291
    Language: English
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 9
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-202-340
    In: Research report
    Description / Table of Contents: CONTENTS: Abstract. - Preface. - Nomenclature. - Introduction. - Theory. - Application. - Literature cited. - Appendix.
    Description / Table of Contents: The equations describing water movement in a dry snow cover are derived and examples of flow through ripe, refrozen and fresh snows are given. The grain size of snow has a large effect on the timing of water discharge. Water is retained by dry snow to raise its temperature and satisfy the irreducible water saturation. These requirements delay and reduce runoff following rain on dry snow.
    Type of Medium: Series available for loan
    Pages: iv, 13 S. : graph. Darst.
    Series Statement: Research report / Cold Regions Research and Engineering Laboratory, CRREL, US Army Material Command 340
    Language: English
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 10
    Call number: ZSP-202-346
    In: Research report / Cold Regions Research and Engineering Laboratory, 346
    Description / Table of Contents: CONTENTS: Abstract. - Preface. - USA CRREL project and personnel involvement. - Part I. Introduction. - Background. - Literature review. - Part II. CRREL investigations from 1970 - 1974. - Initial literature survey (1970). - Oil detection kit development. - Survey of Cape Simpson, Alaska, natural crude oil seepages (1970). - Haines-Fairbanks military pipeline investigations (1971-1973). - Barrow investigations (1970-1974). - Fairbanks and Fox investigations. - Germination studies. - Physiological studies. - Dispersant studies. - Microbiological investigations. - Field investigations of accidental petroleum losses. - Part III. Recent related literature. - Part IV. Conclusions and recommendations. - USA CRREL reports, publications and presentations on Alaska oil spill research. - Literature cited.
    Description / Table of Contents: Knowledge concerning the biological effects of oil pollution on arctic and subarctic terrestrial ecosystems is limited. USA CRREL research personnel conducted investigations from 1970 through 1974 to expand information in this field. Objectives were to: 1) define the ecosystems most sensitive to the presence of crude oil or its refined products, 2) quantify and understand the injury response, and 3) establish time frames for manifestation of damage and natural restorative processes in arctic and subarctic regions. This was accomplished through: 1) surveys of natural oil seepages and past accidential spills in the Arctic and Subarctic, 2) initiation of controlled oil spills and 3) detailed laboratory investigations. Results demonstrated that terrestrial oil spills will to some degree be detrimental to both arctic and subarctic plant communities. Degree and longevity of damage will be influenced primarily by the magnitude of the spill, season of occurrence and existing soil moisture content. Rapid recovery of plant communities subjected to spills will occur only if root systems remain relatively unaffected. Damage will be more extensive and long-term when root systems are saturated with oil. Effects of damage will be manifested gradually over several seasons being influenced by winter stresses. Variation does exist in plant species susceptibility. Carex aquatilis, a predominant sedge of the arctic, is markedly resistant to crude oil damage. In the taiga Picea mariana is very susceptible. Plant recovery can be enhanced through the application of fertilizer. Fertilization, in addition to its direct effect on plant nutrition, will stimulate microbial decomposition of crude oil.
    Type of Medium: Series available for loan
    Pages: vii, 66 Seiten , Illustrationen
    Series Statement: Research report / Cold Regions Research and Engineering Laboratory 346
    Language: English
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 11
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-79/6
    In: CRREL Report, 79-6
    Description / Table of Contents: Nondestructive repetitive plate bearing (RPB) tests were conducted on various test sections in state highways in Maine during 13-15 April 1976. The RPB test consists of making resilient surface deflection measurements during repetitive loadings at various radii from the load plate. The pavement system stiffness was calculated and the resilient modulus values for the various pavement layers were determined with the Chevron computer program for a layered elastic system. A thawed analysis using nondimensional deflection curves for the various sections provided a guide to the susceptibility of the pavement systems to surface failure and pothole development. Some comparisons between stabilized and nonstabilized aggregate and soil were made with calculated stiffness values. The moduli of the various materials were also compared. The residual surface deflections during testing for several pavement systems indicated a linear logarithmic relationship with number of load applications. A relationship between the modulus of the asphalt cement concrete pavement and pavement temperature was developed for the limited temperature range during the testing.
    Type of Medium: Series available for loan
    Pages: v, 20 Seiten , Illustrationen
    Series Statement: CRREL Report 79-6
    Language: English
    Note: CONTENTS Abstract Preface Conversion factors Introduction Descriptions of road test sections Test equipment and procedures. Field repetitive plate bearing tests Data analysis General Layered-elastic analysis of the pavement systems Statistical analysis. Flexural analysis Summary and conclusions Literature cited Appendix A: Resilient surface deflections for the test points
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 12
    Call number: ZSP-201-78/28
    In: CRREL Report, 78-28
    Type of Medium: Series available for loan
    Pages: x, 112 Seiten , Illustrationen
    Series Statement: CRREL Report 78-28
    Language: English
    Note: CONTENTS Abstract Preface Conversion factors Introduction Descriptions of road test sections Test equipment and procedures Field repetitive plate bearing tests Data analysis General Layered-elastic analysis of the pavement systems Statistical analysis Flexural analysis Summary and conclusions Literature cited Appendix A: Resilient surface deflections for the test points
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 13
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-78/25
    In: CRREL Report, 78-25
    Description / Table of Contents: The objectives of this investigation were to describe channel characteristics and geographic settings of ice jam sites from aerial photographic interpretation, to indicate which characteristics may be important in causing ice jams, and to suggest additional uses of aerial photographs. Aerial photographs were taken of 19 sites with a Zeiss RMK 15/23 aerial camera on 17, 19, and 21 April 1976. Uncontrolled photomosaics of each site were assembled and major river characteristics were delineated on the photomosaics. Characteristics described include: manmade structures, falls, rapids, changes in channel depths, channel islands, mid-channel shoals or bars, river bed material, river sinuosity, meanders, floodplain width, riparian vegetation, and types of development on the floodplain. River channel widths were measured from the photographs along rivers where ground truth data were available for comparison. Lengths of channel riffles and pools were measured along the rivers where variations in river depths were evident on the photographs. Seventy-nine percent of the sites have some form of flow control structure which causes a pool with a backwater condition of low velocity. The low flow condition in the pool allows a solid ice cover to form which impedes ice movement and initiates ice jams. Aerial photographs provide a regional perspective for evaluating channel characteristics at an ice jam site and for analyzing the geographic setting at each site during ice-free conditions. Photographs taken after ice jams have formed are useful in monitoring ice jam formation, in analyzing ice characteristics, and in documenting ice jam breakup and movement.
    Type of Medium: Series available for loan
    Pages: iii, 60 Seiten , Illustrationen
    Series Statement: CRREL Report 78-25
    Language: English
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 14
    Call number: ZSP-201-78/23
    In: CRREL Report, 78-23
    Type of Medium: Series available for loan
    Pages: vi, 53 Seiten , Illustrationen
    Series Statement: CRREL Report 78-23
    Language: English
    Note: CONTENTS Abstract Preface Nomenclature Conversion factors: Metric (SI) to U.S. customary units of measurement Introduction Selection of experimental approach Previous investigations of effect of freeze-thaw on soil deform ability Selection of laboratory test method Selection of method of field validation tests Field repeated-load plate-bearing tests Test pavements, soils and materials Test procedures and results Resilient modulus of subgrade calculated from field tests Mathematical model Characterization of asphalt concrete Characterization of frozen silt Calculated resilient modulus of silt within the zone of freezing Laboratory repeated-load triaxial tests Specimens, equipment and testing procedures Apparatus Procedures Resilient properties calculated from laboratory tests Calculation methods Asphalt concrete - test results Asphalt concrete - statistical analysis and discussion Silt - test results Silt - statistical analysis Discussion and conclusions Literature cited Appendix A. Repeated-load plate-bearing test results Appendix B. Laboratory repeated-load triaxial test results Appendix C. Regression equation coefficients for resilient modulus and Poisson’s ratio from repeated-load triaxial test data on asphalt concrete and silt Appendix D. Detailed procedures for repeated-load triaxial testing
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 15
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-78/19
    In: CRREL Report, 78-19
    Type of Medium: Series available for loan
    Pages: iv, 21 Seiten , Illustrationen
    Series Statement: CRREL Report 78-19
    Language: English
    Note: CONTENTS Abstract Preface Introduction Previous work Methods and results Methods of analysis Salinity-chlorophyll a associations Discussion Comparison of ice and water column standing crops Estimated mass of ice associated chl. a Mechanism of ice algae formation in the Weddell Sea Differences between the biological environments of fast and drifting pack ice Conclusions Literature cited Appendix A. Species variations - ice and water column
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 16
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-78/20
    In: CRREL Report, 78-20
    Description / Table of Contents: Abstract: Measurements of the concentrations of Aitken nuclei in maritime air were made near Barrow, Alaska, in June 1975 with a modified Nolan-Pollack small-particle detector. The concentrations varied from 50 to 300 particles cm^-3 depending upon meteorological conditions. The mean Aitken nuclei count was 100 particles cm^-3 for diameters greater than 2 x 10^-3 μm. Transmission electron micrographs of aerosols in maritime air near Barrow were taken. The size range was measured to be 0.01 to 2.5 μm in diameter with the most frequently observed diameter being 0.04 μm. The volume of the maritime air and the collection efficiency of aerosol particles on filmed grids for electron microscopy were measured. The aerosol concentrations were found to be 76 to 101 particles cm^-3 ; the mean concentration was calculated to be 87 particles cm^-3. The aerosol particles in the maritime air were identified by electron microscopy and selected area electron diffraction analysis. About 20% of the aerosol particles were identified, and 80% of the particles were too small for electron diffraction analysis. Sea salt particles constituted 2% of the total, and clay minerals 3%; these particles were considered to be of natural origin. Solid combustion by-products such as coagulated carbon particles and fly ash particles constituted 16%. Despite the comparative remoteness of the sampling site, the measurements indicate that many anthropogenic aerosols were found using an electron microscope.
    Type of Medium: Series available for loan
    Pages: iv, 48 Seiten , Illustrationen
    Series Statement: CRREL Report 78-20
    Language: English
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 17
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-79/3
    In: CRREL Report, 79-3
    Type of Medium: Series available for loan
    Pages: ii, 7 Seiten , Illustrationen
    Series Statement: CRREL Report 79-3
    Language: English
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 18
    Call number: ZSP-201-79/1
    In: CRREL Report, 79-1
    Description / Table of Contents: Experiments were conducted to study the flow of water through columns of homogeneous, repacked snow. The gravity flow theory of water flow through snow was verified, although possibly there is some dependence of the relative permeability on the state of metamorphism of the snow. Also, at very large values of saturation there may be some additional flow in saturated channels.
    Type of Medium: Series available for loan
    Pages: iv, 13 Seiten , Illustrationen
    Series Statement: CRREL Report 79-1
    Language: English
    Note: CONTENTS Preface Symbols Introduction Test procedure Theory Evaluation of the experimental results Example evaluation Results and discussion Literature cited Appendix A. Measured and computed discharge
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 19
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-78/5
    In: CRREL Report, 78-5
    Description / Table of Contents: The viscoelastic deflection of an infinite floating ice plate subjected to a circular load was solved, assuming the Maxwell-Voigt type four-element model. An effective method of numerical integration of the solution integrals was developed, of which each integrand contains a product of Bessel functions extending to infinity. The theoretical curve was fitted to the field data, but the material constants thus found varied with time and location.
    Type of Medium: Series available for loan
    Pages: iii, 32 Seiten , Illustrationen
    Series Statement: CRREL Report 78-5
    Language: English
    Note: CONTENTS Abstract Preface Introduction The problem The solution Method of numerical integration Ramp/steady loading Curve fitting to time lapse deflections Asymptotic deflection Deflection profiles Acknowledgement Literature cited Appendix I. Analytical background Appendix II. Computer programs, ramp time profiles and steady time profiles
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 20
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-78/8
    In: CRREL Report, 78-8
    Description / Table of Contents: The interaction of a 5.1-GHz transverse electric surface wave with a dielectric slab is experimentally investigated. The wave is initially supported by a dielectric substrate resting upon a metallic ground-plane. A slab, made of the same dielectric material as the substrate and variable in height, is then placed upon the waveguide. The results for a small slab sitting on the substrate showed that the discontinuity was a very inefficient launcher of reflected surface waves. Investigations of these reflections with a trough waveguide showed that, for values of slab height comparable to the exponential decay height of the surface wave, the reflections remain very small. However, as the slab height is increased beyond the decay height, the reflected amplitude approaches the theoretical value for a plane wave reflected from the interface between air and the same dielectric. The results are applicable to surface wave methods of microwave deicing of wings and helicopter rotors.
    Type of Medium: Series available for loan
    Pages: v, 16 Seiten , Illustrationen
    Series Statement: CRREL Report 78-8
    Language: English
    Note: CONTENTS Abstract Preface Summary Introduction Background Objective and procedure Theory of plane surface waves Waveguide design and characteristics Physical apparatus Frequency characteristics Spatial distribution of Ey above the guide Guide wave length Surface wave interaction with a slab discontinuity Experiments with a trough Discussion and conclusions Literature cited
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 21
    Call number: ZSP-201-78/9
    In: CRREL Report, 78-9
    Description / Table of Contents: Large, simply supported beams of temperate lake ice were found, generally, to yield significantly higher flexural strengths than the same beams tested in the cantilever mode. Data support the view that a significant stress concentration may exist at the fixed corners of the cantilever beams. Maximum effects are experienced with beams of cold, brittle ice substantially free of structural imperfections; for this kind of ice the strength difference factor, here attributed to the effect of stress concentrations, may exceed 2.0; that is, simply supported beams test a factor of 2 or more stronger than the same beams tested in the cantilever mode. In ice that has undergone extensive thermal degradation, the stress concentration effect may be eliminated entirely. Simply supported beams generally yield higher strengths when the top surfaces are placed in tension. This behavior is attributed to differences in ice type; the fine-grained, crack-free top layer of snow-ice which constituted up to 50% of the ice cover in the current series of tests usually reacted more strongly in tension than the coarse-grained crack-prone bottom lake ice.
    Type of Medium: Series available for loan
    Pages: iv, 14 Seiten , Illustrationen
    Series Statement: CRREL Report 78-9
    Language: English
    Note: CONTENTS Abstract Preface Introduction Test sites and ice cover properties Beam testing Results Discussion Conclusions Literature cited
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 22
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-78/7
    In: CRREL Report, 78-7
    Description / Table of Contents: The theory of non-coaxial in-plane plastic deformation of soils that obey the Coulomb yield criterion is presented. The constitutive equations are derived by use of the geometry of the Mohr circle and the theory of characteristic lines. It is found that, for solving a boundary value problem, the non-coaxial angle must be given such values that enable us to accommodate the presupposed type of flow in the given domain satisfying the given boundary conditions. The non-coaxial angle is contained in the constitutive equations as a parameter. Therefore, the plastic material obeying the Coulomb yield criterion is a singular material whose constitutive equations are not constant with material but are variable with flow conditions.
    Type of Medium: Series available for loan
    Pages: iii, 28 Seiten , Illustrationen
    Series Statement: CRREL Report 78-7
    Language: English
    Note: CONTENTS Abstrac Preface Introduction Analysis of stress Geometry of the Mohr circle Stress characteristic directions Analysis of strain rate Constitutive equations Strain-rate characteristic directions Constitutive geometry Strain-rate tensor The dyadic expression Plastic work rate Coordinate transformation Example The stress solution Velocity equations in the a-characteristic curvilinear coordinates The constant speed solution Velocity equations in the constant density region Solution in the first constant-density subregion Solution in the second constant-density subregion Solution in the passive region Conclusion Literature cited
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 23
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-78/6
    In: CRREL Report, 78-6
    Description / Table of Contents: A new freezing mechanism, called segregation freezing, is proposed to explain the generation of the suction force that draws pore water up to the freezing surface of a growing ice lens. The segregation freezing temperature is derived by applying thermodynamics to a soil mechanics concept that distinguishes the effective pressure from the neutral pressure. The frost-heaving pressure is formulated in the solution of the differential equations of the simultaneous flow of heat and water, of which the segregation freezing temperature is one of the boundary conditions.
    Type of Medium: Series available for loan
    Pages: iv, 13 Seiten , Illustrationen
    Series Statement: CRREL Report 78-6
    Language: English
    Note: CONTENTS Abstract Preface Nomenclature Introduction Segregation freezing Analysis Heat conduction in the nascent ice layer Water flow in the unfrozen soil Heat transfer in the unfrozen soil Energy balance at the segregation-freezing front Numerical computation Literature cited Appendix A. Essence of Portnov’s method Appendix B. Frost-heaving without air available
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 24
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-77/30
    In: CRREL Report, 77-30
    Description / Table of Contents: Abstract: Ageneral computer model to simulate municipal snow removal has been developed. Programs which aid in the routing of snowplows are a part of this package. Once vehicle routes are created, the simulation program can be used to assess situations varying both equipment and meteorological parameters. Time for each plow to complete its route is calculated. Considerations are made for the above variable parameters plus plowing windrow, route starting depth, overlapping truck routes and intersection delay time. The effects of storm length, snowfall rate and starting depth on total plowing time are examined in a test case.
    Type of Medium: Series available for loan
    Pages: ii, 7 Seiten , Illustrationen
    Series Statement: CRREL Report 77-30
    Language: English
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 25
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-77/18
    In: CRREL Report, 77-18
    Description / Table of Contents: Abstract: Models originally developed to describe the arching and the movement of granular materials through hoppers or chutes are applied to the arching and drift of pack ice in straits and gulfs having lengths of 50 to 500 km. Verification of the usefulness of the models is attempted by making comparisons with ice deformation patterns as observed via satellite imagery in the Bering Strait region and in Amundsen Gulf. The results are encouraging in that there is good correspondence between observed arching and lead patterns and those predicted by theory. In addition, values determined via the model for the angle of internal friction (≈ 30° to 35°) and the cohesive strength per unit thickness (≈ 2000 N/m) are similar to values obtained by other approaches. It is estimated that if the wind velocity parallel to the Bering Strait exceeds ≈ 6 m/s, there will be ice flow through the strait.
    Type of Medium: Series available for loan
    Pages: iii, 11 Seiten , Illustrationen
    Series Statement: CRREL Report 77-18
    Language: English
    Note: CONTENTS Abstract Preface Introduction Theory Limiting span of an arch Flow of pack ice through converging channels Stoppage of flow Applications St. Lawrence Amundsen Gulf Bering Strait Conclusion References
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 26
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-77/19
    In: CRREL Report, 77-19
    In: Mechanics of cutting and boring, Part VI
    Description / Table of Contents: Abstract: The report deals with forces and power levels in cutting machines having adisc or drum that rotates about an axis perpendicular to the direction of advance. The forces on individual cutting tools are related to position on the rotor and to characteristics such as tool layout, rotor speed, rotor size, machine advance speed, and rotor torque. Integration leads to expressions for force components acting on the rotor axis, taking into account tool characteristics, cutting depth of the rotor, and rotor torque. These provide estimates of tractive thrust and thrust normal to the primary free surface. For self-propelled machines, this leads to considerations of traction, normal reaction, weight and balance, and power/weight ratios. Specific energy consumption is analyzed and related to machine characteristics and strength ofthe material being cut. Power per unit working area is discussed, and data for existing machines are summarized. Power requirements for ejection ofcuttings are analyzed, and the hydrodynamic resistance on underwater cuttings is treated. A number of worked examples are given to illustrate the principles discussed in the report.
    Type of Medium: Series available for loan
    Pages: vii, 36 Seiten , Illustrationen
    Series Statement: CRREL Report 77-19
    Language: English
    Note: CONTENTS Abstract Preface Foreword Introduction Terminology Forces on individual cutters Torque force and tool force Forces on the rotor axis Tractive thrust and down thrust Alternative tool force formulations Vehicle traction Power/weight ratio Weight and balance Force, torque, speed and power Specific energy Efficiency and performance index Power density Power requirements for ejection of cuttings Hydrodynamic resistance in underwater cutting
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 27
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-77/16
    In: CRREL Report, 77-16
    Description / Table of Contents: A brief discussion is given of the ways an icebreaker breaks ice. Since the icebreaking process is so complex, the solution of a mathematical model does not appear to be feasible. As an alternative, it is suggested that physical models be used to design icebreakers. The appropriate scaling laws for physical models are developed and their practical limitation discussed.
    Type of Medium: Series available for loan
    Pages: ii, 9 Seiten , Illustrationen
    Series Statement: CRREL Report 77-16
    Language: English
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 28
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-77/15
    In: CRREL Report, 77-15
    Description / Table of Contents: A laboratory experimental study was conducted on a scale model of an annular flow ice-water heat sink to be used to store the waste heat produced in a hardened defense installation operating in an isolated mode. The study ex­amined: 1) scaling relationships for predicting the performance of prototype units using data from scale models, 2) the accuracy of a computer prediction technique developed during an earlier study, 3) the heat transfer phenom­enon at the ice-water interface, and 4) some practical aspects related to the operation of a prototype installation. The scaling relationships and the computer program were found to be sufficiently accurate for use in developing a proto­type sink design. During operation the scale model sink provided an almost constant low temperature source of coolant water for approximately one-half its useful life and thereafter behaved like an ordinary stored water reservoir type heat sink. No significant operational problems were discovered.
    Type of Medium: Series available for loan
    Pages: vii, 54 Seiten , Illustrationen
    Series Statement: CRREL Report 77-15
    Language: English
    Note: CONTENTS Abstract Preface Nomenclature Conversion factors: U.S. customary to metric units of measurement Introduction Description of experiment Apparatus Test procedure Experimental results Summary of experimental tests Influence of coolant water flow rates Approximation of the rate of melting Comparison of experimental and computed results Comparative analysis of the model sinks Approximation of the heat transfer coefficient Conclusions and recommendations Literature cited Appendix A. Experimental data, heat sink Model II Appendix B. Heat sink scaling and similarity relationships Appendix C. Derivation of the relationships for the heat transfer coefficient, Reynolds and Nusselt numbers Appendix D. Determination of freezing rates and refrigeration loads Appendix E. Approximation of stresses in the heat sink tank
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 29
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-77/32
    In: CRREL Report, 77-32
    Description / Table of Contents: An experimental study of forced convective heat transfer over a vertical melting plate has been conducted. This study covers water velocities ranging from 1.7 to 9.8 mm/s and bulk water temperatures from 1.11 to 7.50 C. The experimental results are correlated in terms of Nusselt, Prandtl and Reynolds numbers with a moderate correlation coefficient of 0.843. The results are expected to be useful in predicting the heat transfer characteristics of a much larger prototype ice-water heat sink.
    Type of Medium: Series available for loan
    Pages: v, 12 Seiten , Illustrationen
    Series Statement: CRREL Report 77-32
    Language: English
    Note: CONTENTS Abstract Preface Nomenclature Summary Introduction Problem General review of the subject Experimental apparatus General considerations Water reservoir Test chamber assembly Pumping system Electrical control system Experimental procedure Experimental results Discussion and comparison of results Conclusions Literature cited
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 30
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-77/17
    In: CRREL Report, 77-17
    Description / Table of Contents: A literature search was made for information on the accretion of ice on ocean structures and on methods for control. The bulk of the reports were in Russian, with some additional Japanese, British, American, Canadian, and Icelandic sources. Analysis of icing reports indicated that sea spray is the most important cause of ship icing, with lesser amounts due to freezing rain, snow, and fog. Icing is a potential danger whenever air temperatures are below the freezing point of water and the sea temperature is 6 C or lower. Theoretical work on the ice accretion process is discussed, and a method is suggested, based on Russian experiments, for calculating the sea spray accumulation rate for cylindrical and flat surfaces as a function of water source temperature, air temperature, and wind speed. Other factors that influence icing severity are ship size and configuration, angle between ship course and water heading, and ship speed. Icing in the north temperate latitudes generally occurs in the rear of barometric depressions. Maps showing limits of various degrees of icing severity are included. Atmospheric icing measurements on tall land-based structures are presented, and potential maximum accumulations estimated. Control measures are discussed, though no completely effective method is available. Mechanical (impaction) methods are the most common, but experiments have been conducted on heated, icephobic, and deformable surfaces, and with freezing point depressants. No device for the unequivocal measurement of ice accumulation is available, though some experimental methods are suitable for controlled testing; it is recommended that a device be developed.
    Type of Medium: Series available for loan
    Pages: v, 42 Seiten , Illustrationen
    Series Statement: CRREL Report 77-17
    Language: English
    Note: CONTENTS Abstract Preface Conversion factors: U.S. customary to metric units of measurements Introduction The freezing proeess Icing observations Geographical distribution of icing and contributing meteorological conditions Extreme icing conditions Extremes of icc accumulation Prediction of icing occurrences Prediction of icing intensity and rate Control methods Measurement of icing rate Conclusions and recommendations Literature cited Appendix A. Maps of icing occurrence and rate Appendix B. Data for computing ship icing rates Appendix C. Estimation of ice accumulation
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 31
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-77/7
    In: CRREL Report, 77-7
    In: Mechanics of cutting and boring, IV
    Description / Table of Contents: The report deals with the cutting of rock and similar materials by parallel motion tools. It examines cutting forces and energy requirements, taking into consideration tool geometry, wear, operating conditions, and material properties. After an introductory discussion of terminology, some general principles are outlined, and relevant theoretical ideas on metal cutting and rock cutting are reviewed. The next section, which is the heart of the report, reviews experimental data on the magnitudes and directions of cutting forces. There is a graphical compilation of data, including some from obscure or unpublished sources. The variables covered include chipping depth, rake angle, relief angle, side rake, base angle, tool width, tool compliance, tool speed, tool wear, tool interactions, and material properties. The second major part of the report treats the energetics of cutting. It begins with a short discussion of relevant principles, and continues with a compilation and review of experimental data, covering the same independent variables as the force section. The report ends with a concise summary of general behavior for parallel motion tools.
    Type of Medium: Series available for loan
    Pages: xi, 85 Seiten , Illustrationen
    Series Statement: CRREL Report 77-7
    Language: English
    Note: CONTENTS Abstract Preface Foreword Introduction Terminology Principles of cutting Forces acting on a single cutter Theoretical Ideas on cutting Experimental data on cutting forces Effect of chipping depth on tool forces Effect of rake angle on tool forces Effect of relief angle on cutting forces Effect of side rake on tool forces Effect of base angle or face profile on tool forces Effect of rounding at the cutting edge Effect of tool width on cutting forces Tool compliance and force fluctuations Effect of tool speed on cutting forces Effect of rock properties on cutting forces Tool interaction and kerf spacing Effect of multiple pass cutting on tool forces Effect of tool wear on cutting forces Development of wear Energetics of cutting Energetics of parallel-motion tools Variation of specific energy with chipping depth for a single tool Effect of rake angle on specific energy Effect of relief angle on specific energy Effect of side rake on specific energy Effect of base angle or face profile on specific energy Effect of tip radius on specific energy Effect of tool width on specific energy Effect of tool speed on specific energy Variation of specific energy with rock properties Effect of kerf spacing on specific energy Effect of multiple pass cutting on specific energy Effect of tool wear on specific energy General summary Literature cited Appendix Α. Additional data for ice Appendix Β. Conversion factors: U.S. customary and metric units of measurement
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 32
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-76/5
    In: CRREL Report, 76-5
    Description / Table of Contents: Griffith, and later Babel, have previously developed a tensile fracture criterion for a two-dimensional state of stress. This theory is extended to the compression-compression region. From this theory the angle of fracture is developed. The theory is extended conceptually to three dimensions. Triaxial test data by Haynes for snow-ice are shown in this three-dimensional fracture theory. The test data are slightly less than those predicted when the void in the snow-ice is spherical.
    Type of Medium: Series available for loan
    Pages: iii, 9 Seiten , Illustrationen
    Series Statement: CRREL Report 76-5
    Language: English
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 33
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-76/9
    In: CRREL Report, 76-9
    Description / Table of Contents: Access to study areas may be an important factor in long-term field-oriented research, particularly in-regions without well-developed road and communications systems. In a wildland hydrometeorology research project in subarctic Alaska, access to and within a 40-square-mile research watershed has been developed both in accordance with a general plan prepared at project inception and in response to developing research requirements. Foot trails, trails for 'off-road' low-ground-pressure tracked vehicles, helicopter transport, long-term data recorders, and radio telemetry of data have all been incorporated in an access and communications system. Cost estimates indicate that incorporation of gravel roads into the system would be economically advantageous, given adequate funding for initial road construction.
    Type of Medium: Series available for loan
    Pages: iv, 9 Seiten , Illustrationen
    Series Statement: CRREL Report 76-9
    Language: English
    Note: Contents Abstract Preface Conversion factors for U.S. customary and SI units Introduction Access within the Caribou-Poker Creeks Research Watershed Trail access Helicopter access Road access Alternative approaches Long-term recorders Telemetry systems Remote sensing Relative costs A desirable system Selected bibliography
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 34
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-76/12
    In: CRREL Report, 76-12
    Description / Table of Contents: The heat transfer processes associated with melting and refreezing a drill hole 500 m in depth and 0.150 m in initial radius through an ice shelf were approximately analyzed. The results were expressed in graphical form showing the time available for experimentation under the hole as a function of heating duration and heating strength. It was found that the refreezing of the drill hole had a much slower rate than the melting of the hole.
    Type of Medium: Series available for loan
    Pages: vi, 15 Seiten , Illustrationen
    Series Statement: CRREL Report 76-12
    Language: English
    Note: Contents Abstract Preface Summary Nomenclature Introduction Analysis Melting period Freezing period Calculation Conclusion Literature cited Appendix A: Justification of using eq 8 for the calculation of heat transfer coefficient h
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 35
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-76/14
    In: CRREL Report, 76-14
    Description / Table of Contents: At the height of warm weather in Alaska in 1975, temperature measurements were made to determine the extent of the thermal impact on French Creek due to a condenser cooling water impact from the Eielson AFB Power plant. Water temperature measurements during a two-day period failed to show any significant thermal impact on the water in French Creek. It was concluded that no thermal pollution exists due to this warm water input at the volumes and conditions that presently exist.
    Type of Medium: Series available for loan
    Pages: ii, 5 Seiten , Illustrationen
    Series Statement: CRREL Report 76-14
    Language: English
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 36
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-78/26
    In: CRREL Report, 78-26
    Description / Table of Contents: Ice fog suppression experiments on the Fort Wainwright Power Plant cooling pond were conducted during the winters of 1974-76. Baseline information studies occupied a sizable portion of the available ice fog weather in 1974-75. Then hexadecanol was added to the pond and dramatically improved visibility by reducing fog generated from water vapor released by the pond at -14 C. Although this temperature was not low enough to create ice fog, the cold vapor fog created was equally as devastating to visibility in the vicinity of the pond. During the winter of 1975-76, suppression tests were continued using films of hexadecanol, mixes of hexadecanol and octadecanol, and ethylene glycol monobutyl ether (EGME). Suppression effectiveness at colder temperatures was stuided and limits to the techniques were probed. A reinforcing grid was constructed that prevented breakup of the film by wind and water currents. Lifetime tests indicated that EGME degrades much more slowly than either hexadecanol or the hexadecanol-octadecanol mix. The films were found to be very effective fog reducers at warmer temperatures but still allowed 20% to 40% of normal evaporation to occur. The vapor thus produced was sufficient to create some ice fog at lower temperatures, but this ice fog occurred less frequently and was more quickly dispersed than the thick fog that was present before application of the films.
    Type of Medium: Series available for loan
    Pages: iv, 27 Seiten , Illustrationen
    Series Statement: CRREL Report 78-26
    Language: English
    Note: CONTENTS Abstract Preface Introduction Ice fog from cooling ponds Evaporation Relative humidity and cold air Ice fog suppression Air movement Plastic films Rafts Injection wells Cooling towers Chemical films Reinforced film experiments Meteorological data collection Floating reinforcement grid Application of the hexadecanol film Hexadecanol, octadecanol mixes Ethylene glycol monobutyl ether Laboratory tests of suppression effectiveness Conclusions Literature cited Appendix A. Design for an automatic thin chemical film applicationsystem Appendix B. Meteorological data
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 37
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-78/21
    In: CRREL Report, 78-21
    Description / Table of Contents: This study investigates the possibility of providing estimates of the time of occurrence and length of the freezing season for any location in East and West Germany by using the average Januavy air temperature (AJ AT) as an index. The results indicate that reliable values of the mean freezing index can be obtained from the AJAT relationships which are developed for Germany. This association is further verified using data from the northeastern part of the U.S., and the AJ AT is then used to determine the average starting and ending dates (and hence the probable length) of the freezing season for stations in Germany. The AJ AT and the average dates of snowfall occurrence for numerous locations in the U.S. and Germany are also correlated. Interrelationships between these parameters and the average number of days with snow on the ground for stations up to 3000 m in elevation in Germany are examined. A detailed AJ AT map for East and West Germany, in which data from 134 stations, latitude, altitude and regional influences are considered, is developed in order to make the relationships usable. A historical review of the literature on snow studies in Germany and a brief discussion of snow-cover interpretation by satellite photography are included
    Type of Medium: Series available for loan
    Pages: v, 48 Seiten , Illustrationen , 1 Karte
    Series Statement: CRREL Report 78-21
    Language: English
    Note: CONTENTS Abstract Preface Introduction Historical literature review Relationships between midwinter temperature and freezing season Mean freezing index 4 Average January air temperature U.S. comparative study Correlation of AJAT and duration of freezing season Relationships between average January air temperature and snow conditions U.S. relationships German relationships Mapping of average January air temperatures Analysis of observed AJ AT data Development of detailed maps Application and discussion Examples Influence of vegetation Literature cited Appendix A. interpretation of snow cover by satellite Appendix B. Contour, station elevation and Aj AT maps for East and West Germany
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 38
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-78/22
    In: CRREL Report, 78-22
    Description / Table of Contents: Special environmental factors that influence the design, laying and maintenance of undersea pipelines and cables in polar waters are described. Various approaches to the protection of submarine pipes and cables are considered, and prime emphasis is given to burial techniques for shallow water. A wide range of methods for trenching and burying are discussed, and technical data are given.
    Type of Medium: Series available for loan
    Pages: v, 36 Seiten , Illustrationen
    Series Statement: CRREL Report 78-22
    Language: English
    Note: CONTENTS Abstract Preface Conversion factors Introduction Types of pipelines and cables Potential hazards to pipelines and cables Areas of concern Waterdepth Sea ice Icebergs and ice islands Submarine permafrost Ice gouging Seabed erosion by water jets Protection methods Protection of unburied pipes and cables Protection by burial Backhoe digging Wireline equipment Plowing and ripping from the surface Plowing and ripping by self-propelled seabed vehicles Bucket ladder dredges Suction dredging Conventional cutterhead dredges Low pressure water jetting Bottom-traveling cutterhead dredges Explosive methods Novel methods Disc saws, wheel ditchers and milling drums Ladder trenchers and chain saws Repetitive impulse devices High pressure water jets Flame jets and plasma torches Electrical discharge and electromagnetic radiation Chemical methods Conclusions Literature cited
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 39
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-78/24
    In: CRREL Report, 78-24
    Type of Medium: Series available for loan
    Pages: v, 12 Seiten , Illustrationen
    Series Statement: CRREL Report 78-24
    Language: English
    Note: CONTENTS Abstract Preface Introduction Comparison of winters Ship effects Measured forces Sequential breaking of the structure Discussion Conclusions Recommendations Literature cited Appendix A. Force level fluctuations in west ice boom, 20 January 1977
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 40
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-78/18
    In: CRREL Report, 78-18
    Description / Table of Contents: The primary objective of this project was to demonstrate the utility of remote sensing techniques as an operational tool in the acquisition of data required by the U.S. Army Corps of Engineers, Seattle District, in the Grays Harbor dredging effects project, and related projects. Aerial imagery was used to map surface circulation and suspended sediment patterns near the hopper dredge pump site at the harbor entrance and near pulpmill outfalls in Aberdeen, and to map the areal distribution and extent of intertidal habitats. The surface circulation maps prepared from the aerial photographs and thermal imagery compared favorably with the large-scale circulation patterns observed in the Grays Harbor hydraulic model at the U.S. Army Engineer Waterways Experiment Station. Of the imagery provided by NASA, the thermal imagery was more useful than the color or color infrared (CIR) photographs for mapping circula­tion, while the CIR photographs were more useful than the thermal imagery or the color photographs for mapping intertidal habitats. Current velocities estimated from dye dispersion patterns and drifting dye drogues were comparable at some locations to velocities measured by in situ current meters and in the hydraulic model. Based on a cursory evaluation of LANDSAT-1 imagery acquired in January, February, and October 1973, it had limited utility in providing data on surface circulation patterns in Grays Harbor. The areal distribution and extent of nine wetland vegetation types, dune vegetation, and three types of eelgrass were mapped using primarily aerial C IR photographs and ground sur­veys. Color photographs were also used for areas not covered by the C IR photographs. Wetland vegetation types mapped were: low silty marsh, low sandy marsh, sedge marsh, high immature marsh, high mature marsh, salt marsh, diked pasture, freshwater marsh, and wooded swamp. Undiked salt marsh (first five types) covered 5540 acres (22.3 km2) in Grays Harbor.
    Type of Medium: Series available for loan
    Pages: vi, 85 Seiten , Illustrationen
    Series Statement: CRREL Report 78-18
    Language: English
    Note: CONTENTS Abstract Preface Introduction Site description Background and objectives Project history Approach General Aircraft imagery and sensor data LANDSAT imagery Ground truth data Results and discussion Remote sensing techniques Conventional techniques Comparison of results Conclusions Advantages and disadvantages Applications Recommendations Literature cited
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 41
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-78/1
    In: CRREL Report, 78-1
    Description / Table of Contents: The results of axial double point-load tests on disk samples of snow and ice obtained from the area of McMurdo Sound, Antarctica, are presented. They show the effects of temperature, sample length, load point diameter and specific gravity on failure load. It was determined that 13 samples should be tested to obtain a representative mean strength index. The results show that the axial double point-load test has good possibilities as a rapid field test for determining the unconfined comrpessive strength of snow and ice but that further evaluation of the variables affecting test results must be made.
    Type of Medium: Series available for loan
    Pages: iii, 11 Seiten , Illustrationen
    Series Statement: CRREL Report 78-1
    Language: English
    Note: CONTENTS Abstract Preface Introduction Test procedure Test program Test samples Number of test for determining strength index Effect of temperature Effect of sample length Effect of load point size Tests on snow Discussion Recommendations Literature cited
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 42
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-78/2
    In: CRREL Report, 78-2
    Description / Table of Contents: Many of the technical questions relating to iceberg transport are given brief, but quantitative, consideration. These include iceberg genesis and properties, the mechanical stability of icebergs at sea, towing forces and tug characteristics, drag coefficients, ablation rates, and handling and processing the iceberg at both the pick-up site and at the final destination. In particular the paper attempts to make technical information on glaciological and ice engineering aspects of the problem more readily available to the interested planner or engineer. Specific conclusions include: (1) No unprotected iceberg, no matter how long or wide, would be likely to survive the ablation caused by a long trip to low latitudes. (2) Icebergs that have a horizontal dimension exceeding 2 km may well be prone to breakup by long wavelength swells. (3) To avoid the dangers associated with an iceberg capsizing, the width of a 200-m thick iceberg should always be more than 300 m. (4) For towing efficiency the length/width ratio of a towed iceberg should be appreciably greater than unity. (5) For a pilot project, the selected iceberg would have to be quite small, if for no other reason than the practical availability of tug power.
    Type of Medium: Series available for loan
    Pages: v, 31 Seiten , Illustrationen
    Series Statement: CRREL Report 78-2
    Language: English
    Note: CONTENTS Abstract Preface Introduction Sources and properties of tabular icebergs Sources Characteristics of ice shelves near the ice front Characteristics of tabular icebergs Towing Geophysical and engineering considerations Tug characteristics Handling and processing Cutting and boring with thermal devices Penetration with electrothermal devices Electrothermal cutting Making vertical cuts by pre-split blasting Primary fragmentation by blasting Primary fragmentation by mechanical sawing Comminuting ice with machines Slurry pipelines Conclusion Literature cited
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 43
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-77/31
    In: CRREL Report, 77-31
    Description / Table of Contents: Ten roofs in Concord, New Hampshire, were surveyed for wet insulation using a hand-held infrared camera. Suspected wet areas were marked on the roof with spray paint and roof samples were obtained to verify wet and dry conditions. Recommendations for maintenance and repair were made based on infrared findings, water contents, and visual examinations. An incremental economic study is presented to serve as a guide in determining the most cost-effective approach.
    Type of Medium: Series available for loan
    Pages: v, 29 Seiten , Illustrationen
    Series Statement: CRREL Report 77-31
    Language: English
    Note: CONTENTS Abstract Preface Conversion factors: US, customary to metric (SI) units of measurement Introduction Infrared camera Core samples State House State House Annex State Library Legislative Office Building Public Health Complex Highway Garage Fish and Game Offlces Supreme Court John O. Morton Building Department of Health and Welfare Laboratory Economics of roof reinsulation Conclusions and recommendations Literature cited
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 44
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-77/29
    In: CRREL Report, 77-29
    Description / Table of Contents: Results of measurements of salinity, grain size, substructure dimensions and crystal fabrics of the undeformed 2.15-m-thick annual sea ice sheet near Narwhal Island, Alaska, are presented. A notable observation was the formation of a dominant c-axis horizontal structure in all ice below 14 cm, including transformation to a pronounced east-west alignment of the c-axes by a depth of 66 cm. This study confirms earlier reports of the occurrence of very strong horizontal c-axis alignments in arctic fast ice.
    Type of Medium: Series available for loan
    Pages: iii, 8 Seiten , Illustrationen
    Series Statement: CRREL Report 77-29
    Language: English
    Note: CONTENTS Abstract Preface Introduction Sampling and analytical procedures Results Discussion Conclusions Literature cited
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 45
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-77/26
    In: CRREL Report, 77-26
    Description / Table of Contents: A theory for ice forces acting on inclined wedges has been developed, thus making it possible to predict the magnitude of the intermittent ice forces from knowledge of the physical parameters of the system. The theory has been verified by model tests with artificial and natural ice.
    Type of Medium: Series available for loan
    Pages: viii, 26 Seiten , Illustrationen
    Series Statement: CRREL Report 77-26
    Language: English
    Note: CONTENTS Abstract Preface List of symbols Summary Introduction Recent ice research in Denmark General Structures with vertical faces Wedges with inclined faces Recording of the strength of natural ice Artificial ice — properties and manufacture General Composition of material Order of mixing ingredients Rupture theory Theoretical approach Initial contact Forces acting on wedge Maximum force and actual force Principal stress equations 8Dynamic equations Intermittent nature of force Theoretical curve Verifiction of theory by model tests Description Width of rupture channel Plotting of results Engineering application Comparison with Korahavin’s results Recommendations for future research References Appendix A
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 46
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-77/25
    In: CRREL Report, 77-25
    Description / Table of Contents: Results of a study to determine the feasibility of using an impulse radar to detect moisture variations in the built-up roof at CRREL and to monitor the curing of concrete are presented. The results indicate that impulse radar can be used to detect wide variations in roof moisture associated with built-up roof surface deterioration and that this technique has the potential of providing a nondestructive test method for measuring the strength of concrete during curing.
    Type of Medium: Series available for loan
    Pages: iv, 9 Seiten , Illustrationen
    Series Statement: CRREL Report 77-25
    Language: English
    Note: CONTENTS Abstract Preface Conversion factors: U.S. customary to metric units of measurement Introduction Impulse radar system Results and discussion Conclusions and recommendations Literature cited ILLUSTRATIONS Figure Relative locations where impulse radar measurements were made andsamples for moisture determinations were obtained on the CRREL roof Impulse radar signal reflected from metal sheet resting on roof Impulse radar signal reflection from roof at station A Impulse radar surface reflection coefficient versus moisture contentofroof Impulse radar signal reflection from aluminum foil on bottom of con-crete form and from aluminum sheet metal resting on top of form Unconfined compressive strength of concrete versus time Examples of X-Y plots of impulse radar signals obtained during thesounding of concrete slab Impulse radar signal reflection coefficients versus time for acuring concrete slab Calculated impulse radar signal attenuation in concrete slab versuselapsed time Dielectric constants versus time calculated from impulse radar signalInformation obtained during curing of concrete slab Unconfined compressive strength of concrete versus corrected reflec-tion coefficient calculated from impulse radar signal data obtainedduring the curing of concrete slab TABLES Comparison of roof moisture content with radar surface reflection coefficient and dielectric constant
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 47
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-77/14
    In: CRREL Report, 77-14
    Description / Table of Contents: The breakup of the Chena River was observed and documented during the spring of 1975 and 1976. This study attempted to determine the potential for damage to the proposed Chena River flood control dam from ice and debris during breakup. Results of this study were compared to those of a 1974 companion study. In 1975, ice thickness were determined to be 15% thinner than in 1974 and ice volume was 33% smaller. No major ice floes were observed in 1975 and no significant flooding occurred, although the approaches to a bridge at the damsite were eroded by debris and high water immediately after breakup. The 1976 breakup was milder than that of 1975. Minor flooding in the lower river was caused by jamming of a few large ice pieces, but no property damage resulted.
    Type of Medium: Series available for loan
    Pages: v, 44 Seiten , Illustrationen
    Series Statement: CRREL Report 77-14
    Language: English
    Note: CONTENTS Abstract Preface Summary Introduction Ice thickness and quantity Chronology of the 1975 Chena River breakup Checkpoint 3 Checkpoint 4 Checkpoint 5 Checkpoint 6 Checkpoint A Checkpoint 7 Checkpoint C Checkpoint D Checkpoint 8 Checkpoint 10 Checkpoint 11 Checkpoint 12 Spring flooding and debris The 1976 Chena River breakup Breakup in other years Summary and conclusions Appendix A. Sequential photographs of 1975 breakup at checkpoints 3-12
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 48
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-76/16
    In: CRREL Report, 76-16
    In: Mechanics of cutting and boring, (DE-B103)20210225152525
    Description / Table of Contents: This report, which is one of a series on the mechanics of cutting and boring in rock, deals with the kinematics of machines such as rotary drills, augers, tunnel boring machines, corers, and raise borers, in which the rotary cutting unit revolves about an axis that is parallel to the machine's direction of advance. The discussion and analysis cover the geometry and motion of various components of the cutting systems, including such topics as tool trajectories, tool speeds, motions of the more complicated mechanisms, chipping depth, penetration rates, production and clearance of cuttings, tool angles, and spatial distribution of cutters. Worked examples are given to illustrate the application of various equations to practical problems.
    Type of Medium: Series available for loan
    Pages: ix, 45 Seiten , Illustrationen
    Series Statement: CRREL Report 76-16
    Language: English
    Note: CONTENTS Abstract Preface Summary Foreword Terminology Trajectories of fixed tools Trajectories of roller cutters and indenters Speed of fixed cutting tools Speed of rolling disc cutters Speed and geometry of "wide" roller cutters Skidding rollers "Spiked" rollers Epicyclic or planetary mechanisms Chipping depth and penetration rate Chip production and cutting removal rate Balancing cutting and clearing rates in flight augers Tool relief angles - kinematic considerations Tool rake angles Distribution and spacing of cutting tools Radial tool spacing Angular tool spacing Spacing in the axial direction Literature cited
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 49
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-76/11
    In: CRREL Report, 76-11
    Description / Table of Contents: Water flow through the unsaturated portion of a snowpack is calculated using various assumptions about radiation penetration into the snow. The results show that for the purposes of hydrologic forecasting, it is sufficiently ac­curate to assume that all of the radiation absorption occurs at the surface. The error in the calculation of flow is largest for very shallow snowpacks, but this error is reduced by radiation absorption at the base of the snow and by the routing of meltwater through the saturated basal layer.
    Type of Medium: Series available for loan
    Pages: v, 9 Seiten , Illustrationen
    Series Statement: CRREL Report 76-11
    Language: English
    Note: CONTENTS Abstract Preface Summary Conversion factors for U.S. customary and SI units Introduction Theory Examples Discussion Literature cited
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 50
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-76/10
    In: CRREL Report, 76-10
    Type of Medium: Series available for loan
    Pages: vi, 25 Seiten , Illustrationen
    Series Statement: CRREL Report 76-10
    Language: English
    Note: CONTENTS Introduction Experimental work SCR samples CAG samples CMS samples UAG samples SI samples Optical system Equipment Procedure Photographic work Large cracks and fissures Small damage to the surface Small damage to the buIk Results Damage as a function of the position x of the focal point; n(x) Damage as a function of the number of irradiations #; n(#) Damage as a function of crystallographic orientation ĉ; n (ĉ); p (ĉ) Damage as a function of surface structure Damage as a function of age A; n (A) Damage as a function of wavelength λ; p(λ) Systematic study of damage as a function of W, t, m and s; n(W, t, m, s) Analysis Fracture in ice Mechanisms for optically generated damage in transparent dielectrics Discussion of the results Summary and conclusions Literature cited
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 51
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-76/13
    In: CRREL Report, 76-13
    Description / Table of Contents: The thermal structure and ice conditions of Lake Champlain, a mid-latitude large lake, near Shelburne Point, Vermont, were studied during the winter of 1974-75. The lake was instrumented to a depth of 8.5 m with a string of highly calibrated thermistors, connected to a data logger on shore which recorded water temperatures every four hours. An ice mooring system was developed to anchor the thermistor string so that ice and water temperatures could be obtained at known levels. This temperature recording system measured vertical and horizontal variations in ice and water temperature regimes during ice formation, growth and decay. Meteorological data were measured during the winter period November 1974 through March 1975 at the site. Ice stratigraphy was determined for the ice at the site at its maximum seasonal growth for comparison with ice from St. Albans Bay (at the northern end of Lake Champlain) which had formed earlier. Correlations were determined between ice growth and accumulated degree days of freezing. The operation of a bubbler system installed near the measurement site around a service dock was observed.
    Type of Medium: Series available for loan
    Pages: vii, 22 Seiten , Illustrationen
    Series Statement: CRREL Report 76-13
    Language: English
    Note: CONTENTS Abstract Preface Summary Introduction Climate Site selection Instrumentation, measurements and calibration Installation of automatic water temperature recording system Visual observations and ice structure St. Albans Shelburne Analysis Temperature comparison Water temperature measuring system Changes in water temperature Wind Degree-days of freezing Prediction of ice formation Bubbler system Conclusions Recommendations Literature cited
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 52
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-76/15
    In: CRREL Report, 76-15
    Description / Table of Contents: A literature review of revegetation and biological aspects of restoration research was completed for arctic and sub­arctic North America. Although there is a great deal of climatic variation in this region it is generally characterized by extreme conditions, such as a short growing season and permafrost. Most of the revegetation research has been undertaken in the last six years as a result of increased natural resource development. The primary goal has been erosion control, with aesthetics, minimization of thermokarst, and production of browse as other objectives. Revege­tation and long-term restoration methods depend upon such variables as the site conditions, nutrient regime (especially as this is influenced by the climatic conditions in the Arctic and Subarctic), plant adaptations, and the selection of native or introduced species. Technologies which have been developed to meet these conditions primarily include seedbed preparation, use of seed mixes, and fertilization and seeding methods. Most of the research has focused on the use of agronomic grasses and legumes. These are selected on the basis of a number of factors, such as cold hardiness and growth form prior to evaluation in the laboratory and the field. The most successful species to date have been Arctared fescue and Nugget bluegrass in the Arctic, while these two as well as creeping red fescue, meadow foxtail, Frontier reed canarygrass, Durar hard fescue, slender wheatgrass, and Icelandic poa did well in the Subarctic. Similar methods have been attempted to a more limited extent with evaluation of native herbaceous and woody species which seem promising on the basis of natural succession studies. There are a number of continuing research needs for arctic anc subarctic revegetation. These include fertilization strategies, development of specialized techniques (such as sprigging) for native species, and longer term studies. It is particularly important to integrate short term revegetatio methods with long-term restoration goals.
    Type of Medium: Series available for loan
    Pages: iv, 32 Seiten , Illustrationen
    Series Statement: CRREL Report 76-15
    Language: English
    Note: CONTENTS Page Abstract Preface Introduction Definition of revegetation Definition of restoration Objectives Some revegetation considerations Site conditions Nutrient regime Plant adaptations Native species vs introduced species Methods Seedbed preparation Seeding methods Timing of seeding Seed mixes Fertilization Agronomic grasses and legumes Selection criteria Laboratory evaluation Field evaluation Effect of revegetation methods Site conditions Maintenance of herbaceous cover Introduced woody species Native species — succession Significance of disturbance Primary succession Secondary succession Herbaceous native species Selection Laboratory evaluation Field evaluation Effect of revegetation methods Woody native species Selection Laboratory evaluation Field evaluation Native species and agronomic species, in combination Recommendations for research Summary Bibliography Appendix: Species tested
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 53
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-76/21
    In: CRREL Report, 76-21
    Description / Table of Contents: The effects of snow temperature and initial density on the stress vs density and stress vs deformation relationships were investigated for shallow compacted snow in the density range of 0.28 to 0.76 g/cu m, for stress range of 0.5 to 72 bars and a temperature range of -1 to -34 C at a deformation rate of 40 cm/s. A decrease in temperature increases the resistance to stress, the effect increasing with applied stress. For any stress, an increase in the initial density results in an increase in the resulting density, the effect decreasing with an increase in stress. The approximate yield envelopes, which define the stress required to initiate any deformation of snow of a particular density and temperature, were determined. Rapid compaction of snow results in extensive recrystallization, significantly different from that of naturally compacted snow. At a stress of 72 bars, transformation to ice occurs only at temperature above -10C.
    Type of Medium: Series available for loan
    Pages: vi, 47 Seiten , Illustrationen
    Series Statement: CRREL Report 76-21
    Language: English
    Note: CONTENTS Abstract Preface Nomenclature Introduction Description of study Sample preparation Test equipment and procedure Discussion of results Stress-density relationship Stress-deformation relationship Summary and conclusions Microstructural examination of artifically compacted snow Analytical techniques Results and discussion Conclusions Literature cited Appendix: Photographs of oscilloscope traces
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 54
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-76/22
    In: CRREL Report, 76-22
    Description / Table of Contents: Several membrane materials used or considered for MESL (membrane-enveloped soil layer) utilization of poor soils in road construction have been tested for cold effect on puncture and stiffness. PE (polyethylene) film was also tested for solvent soak effects. A simple blunt needle apparatus was devised for puncture testing. For plastic films (mainly PE), both puncture resistance and stiffness increase at low temperature (0 F, -18 C). For non-woven, spunbonded fabrics these properties are little affected by cold. For both non-wovens and PE film, puncture and bending strengths increase linearly with weight or thickness. The slope is steeper for the non-wovens, which generally are stronger on a per unit weight basis. PE film soaked in a hydrocarbon solvent swelled approximately 17% and lost about 30-40% its puncture strength. These effects are apparently reversible upon drying. Consideration has been given to sealing and patching requirements and to the drying of sealant liquids when adhering film to film. Also considered have been pos­sible slippage related to the reported low angle of friction of plastic films in soil and the possibility of lamination for improved membrane properties.
    Type of Medium: Series available for loan
    Pages: v, 60 Seiten , Illustrationen
    Series Statement: CRREL Report 76-22
    Language: English
    Note: CONTENTS Page Abstract Preface Introduction Experimental Materials Apparatus Procedure Results Discussion PE solvent soak and swelling PE solvent soak and puncture Film puncture rate effect Bending orientation Comparative tables and graphs Puncture and temperature Bending and temperature Test result vs thickness and weight General considerations Conclusion and recommendations Literature cited Appendix Detailed data tables Denier explanation
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 55
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-79/8
    In: CRREL Report, 79-8
    Description / Table of Contents: Sea ice ridging statistics obtained from a series of laser surface roughnessprofiles are examined. Each set of profiles consists of six 200-km-long flight tracks oriented approximately perpendicular to the coastline of the Chukchi and Beaufort Seas. The landward ends of the profiles were located at Point Lay, Wainwright, Barrow, Lonely, Cross Island and Barter Island. The flights were made in February, April, August, and December 1976, and one additional profile was obtained north of Cross Island during March 1978. It was found that although there is a systematic variation in mean ridge height (h) with season (with the highest values occurring in late winter), there is no systematic spatial variation in h at a given time. The number of ridges/km (micron) is also high during the late winter, with the highest values occurring in the Barter and Cross Island profiles . In most profiles, the ice 20 to 60 km from the coast is more highly deformed (higher micron values) than the ice either nearer the coast or farther seaward. The Wadhams model for the distribution of ridge heights gives better agreement with observed values in the higher ridge categories than does the Hibler model. Estimates of the spatial recurrence frequency of large pressure ridges are made by using the Wadhams model and also by using an extreme value approach. In the latter, the distribution of the lagest ridges per 20 km of laser track was found to be essentially normal
    Type of Medium: Series available for loan
    Pages: iv, 28 Seiten , Illustrationen
    Series Statement: CRREL Report 79-8
    Language: English
    Note: CONTENTS Abstract Preface Introduction Data collection and processing Analysis General Variations in ridging Ridge height distributions Occurrence of high ridges The tail of the distribution Extreme values Applications to offshore design Conclusions Literature cited Appendix A. Tabulated ice ridge data
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 56
    Call number: ZSP-201-79/7
    In: CRREL Report, 79-7
    Description / Table of Contents: Sediments beneath the Beaufort Sea near Prudhoe Bay, Alaska, were probed at 27 sites using a static cone penetrometer to determine engineering properties and distribution of material types, including ice-bonded sediments. The probe provided both point and casing resistance data and thermal profiles. At five sites these data were correlated with information from adjacent drilled and sampled holes. These control data and the quality of the probe information permitted profiles of sediment type and occurrence of ice-bonded material to be developed along three lines that included various geological features and depositional environments. Material properties were quite variable in the upper 14 m of sediments probed. In general, softer, finer-grained sediments occurred in the upper layers, while penetration refusal was met in stiff gravels to 10 to 12 m below the seabed. Seabed temperatures during the study were all below 0 C. However, because of uncertainties in freezing point values caused by brines, evaluation of the penetration resistance data was required to identify the occurrence of ice-bonded sediments. The coupling of thermal and penetration resistance data revealed that seasonally ice-bonded sediments occurred where the sea ice froze back to or near the seabed. Deeper, perennially frozen sediments also appeared to be present at several probe sites. The penetration data obtained can be used to aid in the design of shallow and deep foundations in both ice-bonded and unfrozen subsea sediments.
    Type of Medium: Series available for loan
    Pages: iv, 49 Seiten , Illustrationen
    Series Statement: CRREL Report 79-7
    Language: English
    Note: CONTENTS Abstract Preface Introduction Equipment Data collection and reduction Data analysis and interpretation Point penetration resistance and material properties Lithologic and temperature profiles Casing penetration resistance Applications Shallow foundations Deep foundations Foundations in permafrost Correlations with laboratory tests Conclusions Selected bibliography Appendix A: Description of penetrometer and test procedures Appendix B: Point resistance and skin friction data
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 57
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-78/27
    In: CRREL Report, 78-27
    Description / Table of Contents: Uniaxial compression and tension tests were conducted on polycrystalline snow-ice to determine the effect of temperature on its strength. Test temperatures ranged from -O.1C to -54C. Two machine speeds, 0.847 mm/s and84.7 mm/s were used for the constant displacement rate tests. The compressive strength at -54C was about oneorder of magnitude higher than at -0.1C. The tensile strength at -18C was about 20% higher than at 0.1C. The initial tangent and 50% strength moduli are given for the compression tests, while the secant modulus to failure is given for the tension tests.The mode of fracture is discussed and the test results are compared with data from other investigations.
    Type of Medium: Series available for loan
    Pages: iii, 22 Seiten , Illustrationen
    Series Statement: CRREL Report 78-27
    Language: English
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 58
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-78/16
    In: CRREL Report, 78-16
    Description / Table of Contents: A model investigation of drifting snow conditions was conducted in a hydraulic flume using a sand-water analog. Model results were evaluated to define modeling parameters that would allow quantitative correlation between measured prototype drift conditions and the model. The modeled structure was the standard plan snow fence designed by the Wyoming Highway Department and installed along Interstate Highway 80 in 1971. The performance of this system was documented by the Rocky Mountain Forest and Range Experiment Station of the U.S. Forest Service. Models of the fence were constructed for three heights and two geometric scales. Geometric scaling was based on terrain roughness and boundary layer thickness considerations, while velocity scaling was based on particle fall velocity and threshold of motion characteristics. Simulation of the atmospheric boundary layer was found to be of primary importance. Velocity scaling analysis suggested the use of a 'significant wind' concept based on a combination of velocity magnitude and frequency. Similarity of precipitation rate was not essential, and could be altered within limits to adjust the time scale. The response of the model to the shape of model elements was significant. Although the model is distorted and inexact similarity is achieved, it appears useful on a practical basis.
    Type of Medium: Series available for loan
    Pages: vi, 26 Seiten , Illustrationen
    Series Statement: CRREL Report 78-16
    Language: English
    Note: CONTENTS Abstract Preface Nomenclature Introduction Background Experimental design Similitude considerations The model Model operation Results Velocity Fence height Porosity Model correlation Summary and conclusions Recommeqdations for future work Literature cited Appendix A
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 59
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-78/15
    In: CRREL Report, 78-15
    Description / Table of Contents: This report first discusses the general approach for calculating the horizontal forces an ice cover exerts on a structure. Ice force determination consists of two parts: (1) the analysis of the in-plane forces assuming that the ice cover remains intact and (2) the use of a failure criterion, since an ice force cannot be larger than the force capable of breaking up the ice cover. For an estimate of the largest ice force, an elastic plate analysis and a failure criterion are often sufficient. A review of the literature revealed that, in the majority of the analyses, it is assumed that the failure load is directly related to a 'crushing strength' of the ice cover. However, observations in the field and tests in the laboratory show that in some instances the ice cover fails by buckling. This report reviews the ice force analyses based on the buckling failure mechanism and points out their shortcomings. The report then presents a new method of analysis which is based on the buckling mechanism
    Type of Medium: Series available for loan
    Pages: iv, 13 Seiten , Illustrationen
    Series Statement: CRREL Report 78-15
    Language: English
    Note: CONTENTS Abstract Preface Introduction and statement of problem Review of relevant analyses and tests Determination of the largest ice force on an isolated structure Preliminary remarks The buckling analysis of a floating wedge Proposed method to determine Literature cited
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 60
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-78/17
    In: CRREL Report, 78-17
    Description / Table of Contents: Abstract: This investigation utilized historical and recent aerial photographs and satellite imagery in 1) estimating changes in positions of the high-water line and sea cliff break and base, in rates of accretion and/or erosion, and in volumes of transported sediment, and 2) providing a preliminary evaluation of the direction of littoral transport along the outer Cape Cod coast. Using aerial photographs acquired in 1938, 1952, 1971 and 1974 with manual photointerpretation techniques, changes in the distances from selected reference points to the cliff break, cliff base and the high-water line were measured. LANDSAT-1 and -2 imagery acquired from 1 September 1972 to 28 May 1975 was evaluated for use in determining the directions of littoral transport that are active the predominant amount of time. Although the imagery has been very useful for this purpose at other locations, it proved to be useless along the outer shore of Cape Cod. Largest net migrations of the high water line from 1938 to 1974 occurred in the northern and southern portions of this coast. The northern maximum high water line was 321.4 ft, the southern was 1794.6 ft. The central portion of the coast was generally more stable with changes varying from 6.8 to 157.6 ft. Cliff-base recession rates varied from 0.4 to 7.3 ft/yr. Maximum estimated net volume of sediment deposited per linear foot of beach from 1938 to 1974 was 334 yd^3 (based on 2 yd^3/ft of recession or accretion); maximum eroded was 914 yd^3. Changes in the configuration of spits were used to evaluate directions of littoral transport since suspended sediment concentrations were generally not sufficient to act as natural tracers of surface currents. Based on the literature and a determination of the portion of the coast perpendicular to the direction of dominant wave approach, the location of the nodal zone for predominant littoral directions of drift probably shifts between the area near Spectacle Pond and North Truro Air Force Station. This investigation has illustrated a photo interpretation technique that is useful in performing a reconnaissance of coastal change. The data obtained from this method can be used to supplement those acquired by ground surveys and are valid as first approximations for planning subsequent, more detailed surveys.
    Type of Medium: Series available for loan
    Pages: vi, 49 Seiten , Illustrationen
    Series Statement: CRREL Report 78-17
    Language: English
    Note: CONTENTS Abstract Preface Conversion factors: U.S. customary to metric units of measurement Introduction Background Previous investigations Analytical procedures Results and discussion Shoreline changes: High-water line Shoreline changes: Cliff recession Volumetric changes Nodal zone location and direction of littoral transport Error evaluation Summary and conclusions Future research Selected bibliography Appendix A: Maps of shoreline with overlays for 1938, 1952, 1971 and 1974 Appendix B: Supplementary data for estimating shoreline change
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 61
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-78/10
    In: CRREL Report, 78-10
    Description / Table of Contents: The compressibility of wet snow is described in terms of pressure melting and nonlinear viscous deformation at grain contacts. The results of experiments with different salinities and liquid water contents are compared with computed densities. The decreasing compressibility of wet snow with increasing salinity and decreasing liquid content is quantified and explained. Simultaneous particle growth and the doubly charged layer at phase boundaries are included in the model. The results show that the density of wet snow increases approximately as a power of time but is highly dependent on the stress, initial particle size, liquid water content, and ionic impurity content of the snow.
    Type of Medium: Series available for loan
    Pages: vi, 23 Seiten , Illustrationen
    Series Statement: CRREL Report 78-10
    Language: English
    Note: CONTENTS Abstract Preface Nomenclature Introduction Experimental procedure Grain growth Stressed particle contacts Fluid pressure Packing geometry Temperature distribution and heat flow Fluid and impurity flows Results The liquid film Conclusions Literature cited
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 62
    Call number: ZSP-201-78/12
    In: CRREL Report, 78-12
    Description / Table of Contents: Road test sections of membrane-enveloped silt and clay soils overlain with asphalt cement concrete were subjected to repetitive dynamic plate-bearing loadings to determine their strength variations during freeze-thaw cycles. The recoverable surface deformations in the load deflection bowl were continuously measured during the loading cycles and analyzed using the Chevron layered elastic computer program to obtain the in situ resilient deformation modulus of the various section layers at different stages of the freeze-thaw cycles. The resilient stiffness of the pavement system (the total load per unit of resilient load plate deflection) was also calculated for the various freeze-thaw conditions. The modulus values of the asphalt cement concrete varied inversely with its temperature by an order of magnetide (90,000 psi to 1,300,000 psi). The resilient stiffness of the pavement system varied in the same manner by nearly a factor of eight (228.4 kips/in. to 1740.2 kips/in.). Despite the wide strength variations of the sections during freeze-thaw cycles, membrane-enveloped fine-grained soils can be utilized instead of granular materials as base and subbase layers in flexible pavements in cold regions where moisture migration is a major concern. Moisture migration did not occur at saturation levels up to 75%, thus there was no strength loss during thawing.
    Type of Medium: Series available for loan
    Pages: v, 24 Seiten , Illustrationen
    Series Statement: CRREL Report 78-12
    Language: English
    Note: CONTENTS Abstract Preface Conversion factors: U.S.customary to metric units of measurement Introduction Freeze-thaw system Construction materials Controlled environment test section Outdoor sections Temperature monitoring instrumentation Repetitive plate bearing test apparatus Test results and analyses Conclusions Literature cited
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 63
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    In: CRREL Report, 79-5
    Description / Table of Contents: Abstract: This report presents data from an experimental program undertaken to develop information on proposed and existing chemical grout solutions to provide engineering properties in connection with grouting of soils in ambient temperatures of 39° ±1°F (3.88°C) and below. Twelve grout solutions were investigated, including organic chemicals, sodium silicates, cements, and clay (bentonite). Set or gel tests were performed on each chemical solution, in the center of which a thermocouple was placed for measuring the rates of heat of reaction, except those of the cements and the clay. These solutions consisted of the mixing portions of the chemicals and were placed into 4-in.-diam by approximately 6-in.-long cylinders at an ambient temperature of 39°F.
    Type of Medium: Series available for loan
    Pages: v, 38 Seiten , Illustrationen
    Series Statement: CRREL Report 79-5
    Language: English
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 64
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-79/4
    In: CRREL Report, 79-4
    Description / Table of Contents: A computer model is described to compute the amount of ice accretion on an object under a variety of initial conditions. Numerical techniques are best applied to these problems because of time dependent effects governing the amount of ice collected and also the variety of initial conditions that can lead to ice accumulation. The helicopter rotor icing problem adds an additional complexity since the velocity along the rotor blade varies over a wide range strongly affecting the amounts of ice collected at different blade positions. The physics of ice accretion is reviewed and the accounting for time-dependence in the computer model is described. Some model results are presented and indicate the dependence of ice accretion on velocity, droplet sizes, cloud liquid water content, and temperature for a cylindrical object of constant size.
    Type of Medium: Series available for loan
    Pages: iii, 39 Seiten , Illustrationen
    Series Statement: CRREL Report 79-4
    Language: English
    Note: CONTENT Abstract Preface Introduction Ice accretion parameters Physics of ice accretion Interaction between water droplets and flow field Time dependence in droplet trajectories Thermodynamic processes at the surface of the object Time dependence in the thermodynamics Time dependence of lesser order Numerical ice accretion model Major subroutines Options for droplet size variations Option for the helicopter rotor case Results Conclusions and future studies Literature cited Appendix A: Computer program
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 65
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-78/13
    In: CRREL Report, 78-13
    Description / Table of Contents: Field observations of the growth fabrics of the fast and near-fast ice along the coasts of the Beaufort and Chukchi Seas show that, at depths of more than 60 cm below the upper ice surface, the sea ice crystals show striking alignments within the horizontal plane. At one site this alignment was well developed at a depth of 15 cm and in all cases the degree of preferred orientation increased with depth, with the strongest orientations occurring at the bottom of the ice sheet. In general the c-axes of the crystals were aligned roughly E-W parallel to the coast. In the vicinity of islands the alignment roughly paralleled the outlines of the islands and in narrow passes between islands the alignment paralleled the channel. Our observations, as well as similar observations made in the Kara Sea by Cherepanov, can be explained if it is assumed that the c-axes of the crystals are aligned parallel to the 'long-term' current direction at the sea ice/sea water interface. The alignments are believed to be the result of geometric selection among the growing crystals, with the most favored orientation being that in which the current flows normal to the (0001) plates of ice that make up the dendritic ice/water interface characteristics of sea ice. It is hypothesized that current flow in this direction reduces the thickness of the solute boundary layer as well as the salinity in the liquid at the interface. This lowered salinity allows crystals in the favored orientation to extend farther into the melt than neighboring crystals with less favored orientations. In addition the current tends to induce a continuous flux of supercooled seawater against the sides of the crystals that extend ahead of the interface.
    Type of Medium: Series available for loan
    Pages: v, 29 Seiten , Illustrationen
    Series Statement: CRREL Report 78-13
    Language: English
    Note: CONTENTS Abstract Preface Introduction Locale and techniques Observations Vertical variations in crystal orientation Regional variations in crystal orientation Summary of observations Causes Initial ice skim Earth’s magnetic field Currents Conclusions and consequences Literature cited
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 66
    Call number: ZSP-201-78/4
    In: CRREL Report, 78-4
    Description / Table of Contents: The use of radio-echo sounding records to indicate the presence of internal layers within large ice sheets is of interest to glaciologists because it offers a means of tracking the internal properties of the ice sheets over large distances. The interpretation of the reflections obtained in this manner is more valuable, however, if a physical property change relating to the glaciological regime can be related to the dielectric property change producing the radio-echo reflections. In this report, we use the measured physical properties of core to bedrock taken at Cape Folger, East Antarctica (66 deg 22 min s, 111 deg (E), 324-m depth), to compute a profile of dielectric properties and from this, a depth-reflection coefficient profile for comparison with observed radio-echo reflections. The measurements available on physical properties are: density variations, bubble size and shape changes, and crystal fabric variations. The depths of the strong reflections shown on the available radio-echo records are in reasonable agreement with the depths corresponding to the highest reflection coefficients computed from the combined physical property measurements. In calculations to differentiate the separate effects of different physical properties, it appears that density variations account for the primary contributions to the calculated dielectric property changes corresponding to the highest reflection coefficients. However, bubble changes alone can also account for reasonable, though lower, reflection coefficients at the appropriate depths. Crystal fabric variations correspond poorly with the reflection locations. Density variations are normally associated with depositional events in the history of the ice sheet.
    Type of Medium: Series available for loan
    Pages: vi, 12 Seiten , Illustrationen
    Series Statement: CRREL Report 78-4
    Language: English
    Note: CONTENTS Abstract Preface Nomenclature Introduction Derivation of the power reflection coefficient-depth variation Possible sources of dielectric constant variation with depth in ice sheets Ice density variations Effect of macroscopic impurity layers Effect of microscopic impurtty layers Changes in inclusion geometry Effect of crystal orientation changes Physical properties of the Cape Folger core Density-depth profile Air bubble-geometry depth profile Crystal orientation-depth profile Radio-echo sounding data Results and conclusions Literature cited
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 67
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-77/11
    In: CRREL Report, 77-11
    Description / Table of Contents: Two performance indicators, effectiveness and thermal efficiency, are defined and used to evaluate the year-round performance of three protected membrane roofs in Alaska and New Hampshire. Effectiveness is a measure of the deviations of ceiling temperatures from a yearly average, with large diviations indicating erratic performance in the roofing-insulation system and small departures indicating a thermally stable system. Thermal efficiency, the ratio of calculated heat loss to measured heat loss, is affected by climatic conditions such as rain, snow, solar radiation and wind. Thermal efficiency values of 100% or greater are possible since the calculated heat loss is based only on the inside and outside air temperature differences and the thermal properties of the roof components. Results of the year-round evaluation indicate that the three protected membrane roofs generally have high values of both effectiveness and thermal efficiency.
    Type of Medium: Series available for loan
    Pages: v, 40 Seiten , Illustrationen
    Series Statement: CRREL Report 77-11
    Language: English
    Note: CONTENTS Abstract Preface Conversion factors: U.S.customary to metric (SI) units of measurement Introduction Location of test sites Fairbanks Anchorage Hanover, N.H. Test program Instrumentation Effectiveness Therma lefficiency Heat balance within the roof Comparisons with conventional systems Conclusions Effectiveness of the test roof Thermal efficiency Heat balance within the roof Applicability Recommendations Literature cited Appendix A. Temperature and heat flow measurements, Anchorage and Fairbanks, Alaska, and Hanover, New Hampshire Appendix B. Thermal efficiencies of the test roof, Anchorage and Fairbanks, Alaska, and Hanover, New Hampshire Appendix C. January 1973 and August 1972 comparisons of protected membrane and conventional built-up membrane systems at Hanover, New Hampshire
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 68
    Call number: ZSP-201-77/9
    In: CRREL Report, 77-9
    Description / Table of Contents: This report presents experimental results on the conditions of initiation of an ice jam by a simple surface obstruction, on the equilibrium thickness of an ice jam formed by accumulation and submergence of ice floes, and on the compression strength of floating, fragmented ice cover. In the study on ice jam initiation, it was found that the minimum concentration of floes in the opening of the obstruction at which a jam occurs is nearly independent of the ratio of width of constricted passage to channel width, and is proportional to a negative power of the ratio of floe length to width of constricted passage. From energy analysis of floe submergence, a relationship relating the thickness of a jam formed by accumulation and submergence of floes to the approach flow characteristics was derived and found to fit satisfactorily the experimental data. In experiments on compression strength of floating, fragmented ice cover it was found that the compressive strength is inversely proportional to compression velocity and independent of cover length.
    Type of Medium: Series available for loan
    Pages: vii, 45 Seiten , Illustrationen
    Series Statement: CRREL Report 77-9
    Language: English
    Note: CONTENTS Abstract Preface List of symbols Introduction I. Initiation of ice jams by partial surface obstructions A. Introductory remarks B. Experimental apparatus and procedure C. Dimensional analysis D. Presentation of results and discussion ΙΙ. Thickness of ice jams due to accumulation and transport of ice floes A. Introductory remarks B. Experimental apparatus and procedures C. Presentation of results E. Conclusion III. Compressive strength of floating fragmented ice covers A. Introductory remarks B. Experimental setup and procedure C. Presentation of results and discussion D. Conclusions Literature cited Appendix A: Experimental results on ice jam initiation Appendix B: Effect of surface tension on submergence velocity of ice floes Appendix C: Experimental results for ice jam thickness study Appendix D: Experimental results on compressive strength of fragmented ice cover
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 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-201-77/8
    In: CRREL Report, 77-8
    Description / Table of Contents: A broadbanded impulse radar system was used for aerial detection of accumulated frazil and brash ice in a 9.5-km reach of the St. Lawrence River near Ogden Island. The remote sensing and data reduction system developed for the project provided data sufficient for production of a contour map having 1-ft intervals. With this contour map, the accumulation pattern of frazil and brash ice could be analyzed. Recommendations are given for improving the performance of the aerial profiling system.
    Type of Medium: Series available for loan
    Pages: iv, 19 Seiten , Illustrationen
    Series Statement: CRREL Report 77-8
    Language: English
    Note: CONTENTS Page Abstract Preface Conversion factors: U.S. customary to metric (SI) units of measurement Background Objectives Profiling system Approach Profiling method Data reduction and interpretation Results Conclusions Recommendations Literature cited Appendix A. Comparison of ground and aerial data
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 70
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-76/1
    In: CRREL Report, 76-1
    Description / Table of Contents: This report summarizes the advances in understanding of the Arctic which have come about since the inception of the ARPA Arctic Surface Effect Vehicle Program in 1970, primarily as the result of CRREL’s participation. Major efforts to increase knowledge of sea ice, terrestrial, and coastal topographic features are described. Special empha­sis is placed upon the quantitative understanding of pressure ridging. Other areas of major interest are atmospheric characteristics and ecological effects. A list of publications generated is included.
    Type of Medium: Series available for loan
    Pages: iv, 28 Seiten , Illustrationen
    Series Statement: CRREL Report 76-1
    Language: English
    Note: CONTENTS Abstract Preface Introduction Sea ice characteristics Ridging intensity Arctic terrain characteristics databank Digital terrain maps Digital laser profiles Standard terrain tapes Mobility analysis Terrestrial and coastal characteristics Northern Alaska Interior Alaska Arctic USSR Northern Canada and Greenland Climatological characteristics General features Surface winds Temperatures Precipitation and visibility Electromagnetic/optical propagation Ecological effects of SEV operations SK-5 tests Simulated SEV tests Conclusions Literature cited Additional CRREL SEV Bibliography
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 71
    Call number: ZSP-201-76/8
    In: CRREL Report, 76-8
    Description / Table of Contents: During the past decade a number of methods for measuring the amount of unfrozen water in partially frozen ground have emerged. Means of quickly and simply predicting unfrozen water contents in clay have become increasingly important with the growth of interest in encapsulating clay soils compacted at low water contents to serve as base courses for roads. Unfortunately the measurements require sophisticated equipment and, in most instances, specially trained operators. In an effort to simplify the task of obtaining water-ice phase composition data, methods of calculating phase composition curves from other, simpler measurements on soils have been sought. The paper presents a method of deriving the measurement of unfrozen water contents at various temperatures from liquid limit determinations.
    Type of Medium: Series available for loan
    Pages: iv, 9 Seiten , Illustrationen
    Series Statement: CRREL Report 76-8
    Language: English
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 72
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-76/3
    In: CRREL Report, 76-3
    Description / Table of Contents: A world-wide review of the literature applicable to the design of harbors and channels in cold regions was conducted. Forces due to ice movement present the dominant factor in the design of marine structures in cold regions. Expressions for calculating the ice force are presented. Other factors relating to design criteria such as construction materials, structure geometry, and methods of ice suppression are discussed.
    Type of Medium: Series available for loan
    Pages: iii, 32 Seiten
    Series Statement: CRREL Report 76-3
    Language: English
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 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-201-76/2
    In: CRREL Report, 76-2
    Description / Table of Contents: The repair and maintenance costs of low slope roofs are high and their life expectancy is less than desired. The increasing use of insulation is accompanied by a greater incidence of problems. The experience in cold regions amplifies these experiences. Protected membrane roofs have the prerequisites for better performance and the experience to date is encouraging. The results of performance measurements of three roofs built by the Corps of Engineers verify that the membrane remains at nearly constant temperature, independent of the weather, and that the insulation retains its integrity despite periodic wetting. Moisture absorption is slow and appears to stabilize in time due to the self-drying nature of the roof. Heat losses are increased due to rain, and extra insulation should be added to compensate for these losses. The resistance of protected membrane roofs to fire, traffic, impact, and other adverse forces is superior. So far, the initial cost of protected membrane roofs is at a premium, primarily due to the cost of concrete pavers. The initial cost premium can be justified, however, by the reduced repair and maintenance costs as indicated to date, and by the longer life expectancy of the protected membrane. The high probability of superior performance and cost effectiveness is a compelling reason to incorporate protected membrane roofs increasingly in Government construction.
    Type of Medium: Series available for loan
    Pages: v, 27 Seiten , Illustrationen
    Series Statement: CRREL Report 76-2
    Language: English
    Note: CONTENTS Page Abstract Preface Introduction Low slope roof problems and repair costs Protected membrane roofs and materials Installations of protected membrane roofs Performance evaluation Test program Effectiveness Thermal efficiency Heat balance Internal cooling due to rain Moisture absorption and thermal conductivity of insulations Durability and life expectancy Fire resistance Patent considerations Costs of roofs Design considerations Proposed specifications Conclusions and recommendations Literature cited
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 74
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-76/4
    In: CRREL Report, 76-4
    Description / Table of Contents: Large areas of grounded sea ice have been reported by early arctic explorers and more recently by the U.S. Coast Guard. The ESSA, ERTS, NOAA and DMSP satellites now provide multispectral imagery with sufficiently high resolution to allow detailed sequential observations to be made of the movement and spatial extent of arctic sea ice. This report discusses the location, formation and decay of five large (greater than 30 sq km) islands of grounded sea ice in the southern Chukchi Sea as observed for an extended period of time using satellite imagery. Measurements of the bathymetry around one grounded sea ice feature are presented along with observations made and photos taken from the ice surface. The potential use of these sea ice islands as research stations is also discussed.
    Type of Medium: Series available for loan
    Pages: v, 24 Seiten , Illustrationen
    Series Statement: CRREL Report 76-4
    Language: English
    Note: Contents Introduction The discovery Age of the island Island visit Other islands of grounded ice Discussion Literature cited
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 75
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-76/6
    In: CRREL Report, 76-6
    Description / Table of Contents: Water flow through the vein structure of temperate ice is described as Darbian flow in which the pressure gradient is determined from vein size and overburden pressure. A solution method for the resulting equation is given and two special cases are considered. For steady flow the equilibrium vein size is a function of depth and, by neglecting the effects of diffusion, it is shown that flow perturbations introduced at the surface propagate downward at a constant speed.These perturbations propagate so slowly that even annual surface fluctuations of flow may be eliminated by diffusion before reaching the bottom of the glacie
    Type of Medium: Series available for loan
    Pages: iii, 5 Seiten , Illustrationen
    Series Statement: CRREL Report 76-6
    Language: English
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 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-201-78/14
    In: CRREL Report, 78-14
    Description / Table of Contents: The analytical solution and the numerical study of the eigenvalue problem for determining the buckling pressure of an infinite elastic plate floating on water and stressed uniformly along the periphery of an internal hole is presented. The boundary conditions considered are the clamped-, simple-, and free-edge conditions. Small buckling pressure occurs only for the free-edge condition. The shape of the deflection for the free-edge condition suggests that buckling is an important mechanism of failure.
    Type of Medium: Series available for loan
    Pages: v, 55 Seiten , Illustrationen
    Series Statement: CRREL Report 78-14
    Language: English
    Note: CONTENTS Abstract Preface Nomenclature Introduction 1. The problem 2. Abstract of the result Part I. Fundamental solutions 3. Fuchsian type solutions 4. Contour integral solution 5. Integration of the integral solution 6. Fundamental solutions for α = 1 7. Fundamental solutions for α = 0 8. Eigenvalues for α = 0 9. Fundamental solutions for α 〉 1 Part II. Asymptotic expansions 10. Asymptotic expansion for 0 〈 α ⩽1 11. Asymptotic expansion for 1 ≦ α ≦ 2 12. Asymptotic expansion for 2 ≦ α ≦ ∞ Part III. Eigenvalues 13. Range of eigenvalues 14. Eigenvalues for the free-edge condition 15. Eigenvalues for the clamped-edge and simple-edge conditions 16. Deflection Acknowledgement Literature cited Appendix A. Analytical continuation at the singular point Appendix B. Tensorial transformations Appendix C. Comparison of the semi-infinite plate buckling with the asymptotic buckling
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 77
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-77/23
    In: CRREL Report, 77-23
    Description / Table of Contents: This report discusses the relationship between an architect and a behavioral scientist. Some of the discussion applies to this cooperative work for design of buildings. The bulk, however, relates to the cooperation of architect and behavioral scientist while conducting research. Examples from collaborative research at Alaskan military installations are cited which demonstrate the roles and contributions of the two disciplines.
    Type of Medium: Series available for loan
    Pages: 8 Seiten , Illustrationen
    Series Statement: CRREL Report 77-23
    Language: English
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 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-201-77/21
    In: CRREL Report, 77-21
    Description / Table of Contents: Cold weather limits the successful application of built-up roofing, but often a roof installation must be completed late in the fall or in the winter. The loose-laid protected membrane roof with a synthetic sheet membrane can be installed in the middle of the winter with complete reliability. A synthetic membrane is traditionally more expensive than built-up roofing (rising crude oil prices, however, have reversed this condition), but it has two special features besides its suitability for winter installation: it can be placed on a damp deck, if necessary, and, being losse-laid, it does not split because of deck movement. This report documents information on the installation of two roofs in Anchorage, Alaska, during January and February 1972, including a discussion of the necessary snow removal from the bare deck and the use of portable shelters for preparing the lap joints between sheets during very cold weather. The winter installation caused no special construction problems and the advantages of the synthetic membrane make it an attractive alternative to built-up roofing. The cost of loose-laid protected membrane roofs in Alaska was, in 1972, nearly $300 per square ($28/sq.m), including insulation. Prices are rising as labor costs rise and as more insulation is specified.
    Type of Medium: Series available for loan
    Pages: 5 Seiten , Illustrationen
    Series Statement: CRREL Report 77-21
    Language: English
    Note: CONTENTS Abstract Preface Introduction The protected membrane roof Winter construction considerations Construction costs Conclusion
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 79
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-77/28
    In: CRREL Report, 77-28
    Description / Table of Contents: Tests were conducted to assess the extent of surface degradation resulting from the application of non-chloride deicing chemicals on three types of airfield pavements. The chemicals tested were proprietary mixtures of urea, formamide, and ethylene glycol; sodium chloride, distilled water, and dry specimens were used as controls and for comparison. Pavements included new and old specimens of open-graded asphaltic concrete and old specimens of dense-graded asphaltic concrete. Portland cement concrete specimens used were new and old, with and without air-entrainment. New and old tar rubber concrete specimens were also tested. Samples were subjected to up to 60 freeze-thaw cycles with deicing chemicals flooding their upper surface. Each specimen was rated on a scale of 0-5 after every five freeze-thaw cycles. All PCC specimens showed some surface degradation, whereas the dense- and open-graded asphaltic concretes were largely unaffected.
    Type of Medium: Series available for loan
    Pages: v, 16 Seiten , Illustrationen
    Series Statement: CRREL Report 77-28
    Language: English
    Note: CONTENTS Abstract Preface Conversion factors: U.S. customary to metric (SI) Units of measurement Introduction Test procedure Pavement types Deicing chemicals Description of tests Discussion Literature cited Appendix A: Test results Appendix B: Portland cement concrete materials data
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 80
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-77/27
    In: CRREL Report, 77-27
    Description / Table of Contents: The spectral reflectance of natural snow in the range of 0.20- to about 0.40-micrometers wavelengths was studied in the laboratory using both continuous spectral scanning and fixed bandpass measurements. White barium sulfate pressed powder was used as a standard for comparison. The reflectance of fresh snow was found to be very high (usually nearly 100%) and only weakly wavelength dependent from 0.24 micrometers to the visible range. In the 0.20- to 0.24-micrometers portion of the spectrum, the reflectance was found to be quite erratic. Possible reasons for the irregularities in reflectance measurements are discussed.
    Type of Medium: Series available for loan
    Pages: v, 19 Seiten , Illustrationen
    Series Statement: CRREL Report 77-27
    Language: English
    Note: CONTENTS Abstract Preface Introduction Experimental procedure Snow collection Spectrophotometric methods Data analysis Potential sources of error Presentation of results Continuous-scan measurements Comparison of sequential bandpass and continuous-scan measurements Theoretical calculations Discussion of results Differences in amplitude of reflectance measurements Irregularities in the shape of spectral reflectance curves The true spectral reflectance of snow in the ultraviolet region Conclusions Literature cited Appendix A. Absolute reflectance values of pressed BaSO4 powder
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 81
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-78/3
    In: CRREL Report, 78-3
    Description / Table of Contents: The mathematical theory for the bearing capacity of river ice for vehicles is presented. The floating ice sheet is assumed to have simple supports at the shore line. Solutions are presented for loads uniformly distributed over circular and rectangular areas. Numerical evaluations are made for a number of vehicles and the results presented in graphical form
    Type of Medium: Series available for loan
    Pages: iii, 22 Seiten , Illustrationen
    Series Statement: CRREL Report 78-3
    Language: English
    Note: CONTENTS Abstract Preface Conversion factors: U.S. customary to metric (SI) units of measurement Introduction Theory Solution by superposition Solution by Fourier integral Solution by Fourier series Application and results Literature cited Appendix A: Bearing capacity of river ice for military vehicles Appendix B: Vehicle specifications Appendix C: Fortran II computer program
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 82
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-77/12
    In: CRREL Report, 77-12
    Description / Table of Contents: A computer program to calculate the increased live load on a snow-covered roof due to rain-on-snow is given. For the 25-year rainstorm falling on a heavy snow load on a flat roof in Hanover, New Hamsphire, and additional 98 kg/m2 (20 lb/ft2) of liquid water is added to the live load. The additional load due to rain-on-snow is very sensitive to the snow properties and characteristics of the roof. A wide range of live loads is possible, depending on the particular circumstances.
    Type of Medium: Series available for loan
    Pages: vii, 19 Seiten , Illustrationen
    Series Statement: CRREL Report 77-12
    Language: English
    Note: CONTENTS Page Abstract Preface Summary Nomenclature Introduction Water movement through snow Vertical percolation Lateral flow Flat roofs Sloping roofs Rainfall intensity-duration effects Miscellaneous effects Radial flow to drains Flow along gutters on snow-covered roofs Snow structure Basal layer Conclusion Literature citied Appendix A. Computer program calculating roof loads from rain-on-snow
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 83
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-77/10
    In: CRREL Report, 77-10
    Description / Table of Contents: Abstract: The amount of force that an ice sheet can apply to a vertical pile was tested by lowering a hydraulic ram device into a hole cut in an existing ice sheet. The device had a large base and shoved a relatively narrow vertical pile in a horizontal direction. Test variables were: pile widths - 1.5 in. to 36.7 in.; pile shapes - flat, round, 45 ° and 90° wedges; ice thickness - 2.6 in. to 8.8 in.; and ram speed - 0.07 in./sec to 18.75 in./sec; but not all shapes and sizes were tested at all speeds. Air temperature was 20 ° F (-6.7 ° C). Forces and displacements were measured electronically. The findings are presented as a table of test results and as bar graphs of the resultant ice pressures versus the pile width-to-ice-thickness ratio, pile width and shape combination and pile velocity. The types of failures in the ice sheet were classified as crushing, splitting, buckling, bending, and creeping. The ice sheet generally withstood a high initial load followed by several lower peak load levels. The maximum ice pressure measured was 610 psi for a 12.6-in.-diam round pile in 8.4-in.-thick ice.
    Type of Medium: Series available for loan
    Pages: iv, 9 Seiten , Illustrationen
    Series Statement: CRREL Report 77-10
    Language: English
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 84
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-76/17
    In: CRREL Report, 76-17
    In: Mechanics of cutting and boring, (DE-B103)20210225152525
    Description / Table of Contents: This report, which is one of a series on the mechanics of cutting and boring in rock, deals with the kinematics of machines which utilize a continuous belt as the cutting unit (e.g. coal saws, shale saws, digger-chain trenchers). The discussion and analysis cover the geometry and motion of various components of the cutting system, including such topics as chipping depth, production and conveyance of cuttings, tool trajectories, tool speeds, tool angles, and arrangement of cutting tools on the belt. Worked examples are included to illustrate the application of various equations to practical problems
    Type of Medium: Series available for loan
    Pages: viii, 24 Seiten , Illustrationen
    Series Statement: CRREL Report 76-17
    Language: English
    Note: Contents Abstract Preface Summary Foreword Introduction Terminology Chipping depth Production and conveyance of cuttings Tool trajectories Tool speeds Tool relief angles — kinematic considerations Tool rake angles Belt curvature, slackness and flexibility Tool layout Longitudinal tool spacing Transverse tool spacing Cross-section profiles of the kerf Literature cited
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 85
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-76/20
    In: CRREL Report, 76-20
    Description / Table of Contents: Under ordinary conditions the freezing of water begins with supercooling and ice nucleation, and proceeds at 0°C at the ice/water interface until ice formation stops. The presence of solutes, high pressure, or dispersal in fine pores causes the water to freeze at temperatures below 0°C (the so-called freezing point depression). Whenever freezing begins, it pro­ceeds at a constant temperature, or at a temperature which becomes progressively lower. A temperature rise during ice formation is considered here to be an anomaly. Under all equal circumstances, the conditions under which an anomal­ous freezing temperature is observable appear to be very special. This report describes two different experiments dis­playing the anomalous rise of temperature after nucleation and during ice formation. In one case the water was dispersed in the fine pores of fine powders; in the other case pure water was frozen in a transparent insulated cell. Photographic observations were made; relations of ice surface to water volume were measured.
    Type of Medium: Series available for loan
    Pages: iv, 23 Seiten , Illustrationen
    Series Statement: CRREL Report 76-20
    Language: English
    Note: CONTENTS Page Abstract Preface Conversion factors for U.S.customary and SI units Introduction Materials, instruments, measurements Experiments with water freezing in fine pores Freezing experiments with bulk water Summary and conclusions Literature cited
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 86
    Call number: ZSP-201-76/18
    In: CRREL Report, 76-18
    Description / Table of Contents: Three surface elevation and ice thickness profiles obtained during the 1972 Arctic Ice Dynamics Joint Experiment on a multiyear ice floe were analyzed to obtain relationships between surface elevation, thickness and physical properties of the ice. It was found that for ice freeboards from 0.10 m to 1.05 m above sea level a linear relationship between ice density and freeboard could be postulated. The equation for the regression line is: Ice density = -194f' + 974 kg/cu m where f' is the ice freeboard plus snow depth in ice equivalent at the point in question. This statistical relationship is consistent with observed physical properties, which indicate that as the ice freeboard increases, ice salinity decreases and the higher freeboard or thicker ice therefore decreases in density. Using this variable density with freeboard relationship, a model was constructed to predict ice thickness, given ice freeboard and snow depth alone. This prediction is desirable, since snow depth and freeboard are relatively easy to obtain, whereas ice thickness can usually be obtained only by drilling through the ice. The model was compared with two other models. It was found that the variable density prediction model gave the best approximation to observed ice thickness, with a standard error between the measured and predicted value of about 0.4 m, compared with errors from 50 to 100% higher for the other two models.
    Type of Medium: Series available for loan
    Pages: v, 25 Seiten , Illustrationen
    Series Statement: CRREL Report 76-18
    Language: English
    Note: Contents Abstract Preface Summary Introduction Previous work Results Models for predicting thickness from ice freeboard Comparison between measured and predicted thicknesses Spectral behavior of measured and predicted profiles Comparisons of ice thickness using airborne laser profilometry Conclusions Literature cited Appendix A: Misgivings on isostatic imbalance as a mechanism for sea ice cracking
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 87
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-76/7
    In: CRREL Report, 76-7
    Description / Table of Contents: This report covers a series of cantilever beam tests designed to determined the efficacy of adding reinforcement to an ice cover. Tests were run using 1-in.-diam tree branches, 3/16-in.-diam wire rope and 9/16-in. half-round wood dowels as reinforcement for both seawater and freshwater ice. The results show a definite advantage derived from using reinforcement, even when poorly placed. The results also show that reinforced ice carries a load even after it cracks. Thus, after the initial cracks there is time to remove people and equipment before final breakthrough. One must bear in mind, however, that reinforcement has disadvantages. The darker reinforcement absorbs solar radiation and thereby causes earlier weakening of the ice cover. Also, in many cases the time and effort required to place reinforcement may exceed those required to achieve equal strength by additional thickening of the ice sheet. This study has shown that understanding of the failure mechanism of ice under repetitive loading is poor and that future studies should be performed on this problem. Also, this study covered only cantilever beams. The actual field problem is strengthening a three-dimensional sheet. Hence, distribution and orientation of the reinforcement should be addressed in future studies.
    Type of Medium: Series available for loan
    Pages: v, 12 Seiten , Illustrationen
    Series Statement: CRREL Report 76-7
    Language: English
    Note: Contents Abstract Preface Summary Conversion factors: U.S. customary to SI metric units Introduction Typical methods of constructing ice bridges Current knowledge Test program Objectives Equipment Procedure Data General Specific ice sheets Test results Conclusions Recommendations Literature cited
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 88
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-76/23
    In: CRREL Report, 76-23
    Description / Table of Contents: This report describes the study of piles tested in polar snow at Camp Century, Greenland. More than 20 piles of various lengths and sizes were driven, including timber, closed-end and open-end steel pipe piles, and I- and H-piles. The H-piles were instrumented with strain gages. In addition to the driven piles, two purely end-bearing piles were installed in augered holes and five piles were frozen in place using a snow-water slurry. Driving records were obtained and are discussed. Analysis of the driving response of various piles revealed that the Hiley formula, and presumably other similar pile driving formulas, cannot be used to predict the ultimate supporting capacity of piles driven in snow. Factors such as pile inertia, rigidity, size, and tip resistance are discussed in relation to their apparent influence upon pile penetration. Pile load test procedures are described and test results are discussed. It was found that closed-end pipe piles are decidedly inferior to open-end pipe piles in their load-carrying capability and their ultimate supporting capacity. Although pile settlement was found to be dependent upon such variables as pipe load, time, pile shape, and snow temperature, precise effects of these variables were not determined. Nevertheless, the capability of open-end piles to carry quite heavy loads was demonstrated and a procedure is presented for testing these piles in snow.
    Type of Medium: Series available for loan
    Pages: ix, 132 Seiten , Illustrationen
    Series Statement: CRREL Report 76-23
    Language: English
    Note: Contents Abstract Preface Introduction Test site Pile driving equipment Test instrumentation Testing procedures Pile driving data Pile type vs driving resistance Closed-end vs open-end piles Calculated bearing capacity of pile Effect of pile driving on the embedment medium Pile inclination Slurried-in-place piles Pile load test data Strain gage instrumentation and results Pile excavation Discussion and conclusions Literature cited Appendix A: Theoretical elastic deflection of piles supported by skin friction Appendix B: Trench floor arching study
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 89
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-202-336
    In: Research report
    Description / Table of Contents: CONTENTS: Abstract. - Preface. - Nomenclature. - Introduction. - Description of study. - Sample preparation. - Test equipment and procedure. - Discussion of results. - Stress-density relationship. - Effect of rate of deformation. - Effect of temperature. - Effect of initial snow density. - Stress-deformation relationship. - Summary and conclusions. - Microstructural analysis. - Introduction. - Analytical methods. - Results and discussion. - Conclusion. - Literature cited. - Anpendix: Test data.
    Description / Table of Contents: The effects of snow temperature, rate of deformation, and initial density on the stress vs density and stress vs deformation relationships were investigated in the pressure range of 0.1 to 75 bars. The rate of deformation in the range of 0.027 to 27 cm sec^-1 does not have a significant effect. A decrease in temperature in the range of 0° to -40°C increases the resistance to stress and deformation, the temperature effect increasing with applied pressure and initial density. The effect of initial density is significant. For any stress, an increase in the initial density results in an increase in the resulting density, particularly at low stress levels and at temperatures near 0°C. The texture of artificially compacted snow is significantly different from that of naturally compacted snow of the same density because of the very short recrystallization time period.
    Type of Medium: Series available for loan
    Pages: iv, 57 Seiten , Illustrations
    Series Statement: Research report / Cold Regions Research and Engineering Laboratory, CRREL, US Army Material Command 336
    Language: English
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 90
    Call number: ZSP-202-347
    In: Research report / Cold Regions Research and Engineering Laboratory, 347
    Description / Table of Contents: CONTENTS: Abstract. - Preface. - Introduction. - Experimental. - Results and discussion. - Applications. - Literature cited.
    Description / Table of Contents: Chemical analysis of century-old ice from continuous 5 to 7 year intervals of three ice cores from south and central Greenland (Dye 3, Milcent and Crete) show maximum concentrations of Na, Mg,Ca, K, and Al during early spring and minimum concentrations during late summer and early fall. Peak spring values are as much as 10 times greater than fall values. Because of the large seasonal chemical variations, samples used for depth-age or annual deposition rate studies must represent accumulation from exactly one year or whole multiples of a year. The seasonal chemical variations seem promising as a new method of defining annual layers and thus dating old ice cores.
    Type of Medium: Series available for loan
    Pages: iii, 5 Seiten , Illustrationen
    Series Statement: Research report / Cold Regions Research and Engineering Laboratory 347
    Language: English
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 91
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-202-310
    In: Research report
    Description / Table of Contents: CONTENTS: Introduction. - Field sites and procedures. - Results. - Discussion. - Conclusions. - Literature cited. - Appendix A: Tabulation of AIDJEX core data. - Appendix B: Tabulation of average salinity/ice thickness data. - Abstract.
    Description / Table of Contents: The salinity distribution in multiyear sea ice is dependent on the ice topography and cannot be adequately represented by a single average profile. The cores collected from areas beneath surface hummocks generally showed a systematic increase in salinity with depth from 0 0/00 at tne surface to about 4 0/00 at the base. The cores collected from areas beneath surface depressions were much more saline and displayed large salinity fluctuations. Salinity observations from sea ice of varying thicknesses and ages collected at various arctic and subarctic locations revealed a strong correlation between the average salinity of the ice, S, and the ice thickness, h. For salinity samples collected from cold sea ice at the end of the growth season, this relationship can be represented by two linear equations: S = 14.24 - 19.39h (h? 0.4 m) ; S = 7.88 - 1.59h (h 〉 0.4 m) . It is suggested that the pronounced break in slope at 0.4 m is due to a change in the dominant brine drainage mechanism from brine expulsion to gravity drainage. A linear regression for the data collected during the melt season gives S = 1.58 + 0.18h. An annual cyclic variation of the mean salinity probably exists for multiyear sea ice. The mean salinity should reach a maximum at the end of the growth season and a minimum at the end of the melt season.
    Type of Medium: Series available for loan
    Pages: iii, 23 Seiten , Illustrationen
    Series Statement: Research report / Cold Regions Research and Engineering Laboratory, CRREL, US Army Material Command 310
    Language: English
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 92
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-83/2
    In: CRREL Report, 83-2
    Description / Table of Contents: A numerical model of rime ice accretion on an arbitrary two-dimensional airfoil is presented. The physics of the model are described and results are presented that demonstrate, by comparison with other theoretical data and experimental data, that the model predictions are believable. Results are also presented that illustrate the capability of the model to handle time-dependent rime ice accretion, taking into account the feedback between the ice accretion and the airflow and droplet trajectory fields.
    Type of Medium: Series available for loan
    Pages: vi, 81 Seiten , Illustrationen
    Series Statement: CRREL Report 83-2
    Language: English
    Note: CONTENTS Abstract Preface Nomenclature Introduction Methodology Potential flow around an arbitrary airfoil Incompressible velocity field Droplet trajectory equation Computational procedure for trajectories Determining the point of impact Calculation of collision efficiencies Accreting an ice layer Determining the accuracy of the flow field Determining the accuracy of the trajectories Results and discussion Comparing results with and without the history term Collision efficiency of NACA 0015 airfoil at 8° attack angle Time-dependent accretion on NACA 0015 airfoil at 8° attack angle Time-dependent accretion on NACA 0015 airfoil at 0° attack angle Conclusions and recommendations Literature cited Appendix A : Sample input Appendix B: Sample output Appendix C : Program listing
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 93
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-84/19
    In: CRREL Report, 84-19
    Description / Table of Contents: In this study a method for making long-range forecasts of freeze-up dates in rivers is developed. The method requires the initial water temperature at an upstream station, the long-range air temperature forecast, the predicted mean flow velocity in the river reach, and water temperature response parameters. The water temperature response parameters can be either estimated from the surface heat exchange coefficient and the average flow depth or determined empirically from recorded air and water temperature data. The method is applied to the St. Lawrence River between Kingston, Ontario, and Massena, New York, and is shown to be capable of accurately forecasting freeze-up. Originator-supplied keywords include: Ice formation, and River ice.
    Type of Medium: Series available for loan
    Pages: iii, 22 Seiten , Illustrationen
    Series Statement: CRREL Report 84-19
    Language: English
    Note: CONTENTS Abstract Preface Introduction Problem formulation Analytical treatment Application to the upper St. Lawrence River Summary Literature cited Appendix A: Basic program for St. Lawrence River freeze-up forecast
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 94
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-83/1
    In: CRREL Report, 83-1
    Description / Table of Contents: Roof snow load case studies gathered throughout the United States over a three-year period are analyzed. The objective of the analysis is to determine a relationship between the snow load on the ground and the corresponding uniform snow load on flat and sloped roofs. The main parameters considered are the thermal characteristics of the roof, the roof slope and the exposure of the structure. Exposure has the strongest effect on the ratio of ground to roof snow loads. Comparisons are made with existing and proposed building codes and standards.
    Type of Medium: Series available for loan
    Pages: iv, 47 Seiten , Illustrationen
    Series Statement: CRREL Report 83-1
    Language: English
    Note: CONTENTS Abstract Preface Metric conversion table Introduction Data base Conversion factor Ground load effects Exposure effects Thermal effects Slope effects Expected value relationship Comparison with existing codes and standards Comparison with relationships proposed in new ANSI standard Summary and conclusions Literature cited Appendix A. Roof snow load case history reports Appendix B. Roofs in the snow load case study data base Appendix C. Ground and roof snow load data Appendix D. Conversion factors from the 1982 ANSI standard
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 95
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-84/17
    In: CRREL Report, 84-17
    Description / Table of Contents: VHF-band radiowave short pulses were transmitted within the permafrost tunnel at Fox, Alaska, over distances between 2.2 and 10.5 m. The propagation medium was a frozen silt containing both disseminated and massive ice with temperatures varying from -7°C near the transmitter to probably -2 C near the center of the tunnel overburden. The short pulses underwent practically no dispersion in the coldest zones but did disperse and refract through the warmer overburden, as suggested by calculations of the effective dielectric constant. Most significantly the measured frequency content decreased as the effective dielectric constant increased. The results indicate that deep, cross-borehole pulse transmissions over distances greater than 10 m might be possible, especially when the ground is no warmer than -4°C. The information thus pined could be used for identifying major subsurface variations, including ground ice features.
    Type of Medium: Series available for loan
    Pages: ii, 14 Seiten , Illustrationen
    Series Statement: CRREL Report 84-17
    Language: English
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 96
    Call number: ZSP-201-84/16
    In: CRREL Report, 84-16
    Description / Table of Contents: Phase composition curves are presented for a typical saline silt from Lanzhou, P.R.C., and compared to some silts from Alaska. The unfrozen water content of the Chinese silt is much higher than that of the Alaskan silts due to the large amount of soluble salts present in the silts from China, which are not present in silt from interior Alaska. When the salt is removed, the unfrozen water content is then similar for both the Chinese and Alaskan silt. Here we introduce a technique for correcting the unfrozen water content of partially frozen soils due to high salt concentrations. We calculate the equivalent molality of the salts in the unfrozen water at various temperatures from a measurement of the electrical conductivity of the extract from saturated paste.
    Type of Medium: Series available for loan
    Pages: iii, 25 Seiten , Illustrationen
    Series Statement: CRREL Report 84-16
    Language: English
    Note: Contents Abstract Preface Introduction Background Materials Sample preparation Nuclear magnetic resonance Specific surface area Electrical conductivity Results and discussion Summary Literature cited Appendix A: Unfrozen water content vs temperature data for Lanzhou silt
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 97
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-84/18
    In: CRREL Report, 84-18
    Description / Table of Contents: This report investigates the influences of turbulence and water temperature on frazil ice formation. The rate and thequantity of frazil ice formed in a specified volume of supercooled water increase with both increasing turbulence inten-sitv and decreasing water temperature. The influence of turbulence intensity on the rate of frazil ice formation, how-ever. is more pronounced for larger initial supercooling. The turbulence characteristics of a flow affect the rate offrazil ice formation by governing the temperature to which the flow can be supercooled, by influencing heat transferfrom the frazil ice to surrounding water, and by promoting collision nucleation, particle and floc rupture and increasingthe number of nucleation sites. larger frazil ice particles formed in water supercooled to lower temperatures. The par-ticles usually were disks, with diameters several orders greater than their thickness. Particle size generally decreased with increasing turbulence intensity. This report develops an analytical model, in which the rate of frazil ice formation isrelated to temperature rise of a turbulent volume of water from the release of latent heat of fusion of liquid water toice. Experiments conducted in a turbulence jar with a heated, vertically oscillating grid served both to guide and tocalibrate thanalytical'model as well as to afford insights into frazil ice formation. The formation of frazil ice wasstudied for Vemperatures of supercooled water ranging from -0.9° to -0.050°C.
    Type of Medium: Series available for loan
    Pages: vi, 50 Seiten , Illustrationen
    Series Statement: CRREL Report 84-18
    Language: English
    Note: CONTENTS Abstract Preface Nomenclature Introduction Background Scope of study Literature review Introduction Incipient formation of frazil ice Particle size and evolution of frazil ice Influences of turbulence and water temperature on the rate of frazil ice formation Conclusions Analytical model Introduction Elements of heat transfer Elements of turbulence Experimentation Experimental apparatus Experimental procedure Results Introduction Nucleation of frazil ice Influences of turbulence on frazil ice formation Water temperature Influences of water temperature and turbulence on the concentration of frazil ice Frazil ice particle shape and size Conclusions Literature cited Appendix A: Preliminary frazil ice experiments Flume experiments Couette-flow Appendix B: Listing of computer program for calculation of frazil ice formation Appendix C: Water temperature rise attributable to frazil ice formation as computed usingthe analytical model .
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 98
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-84/12
    In: CRREL Report, 84-12
    Description / Table of Contents: Icing on stationary structures such as oil rigs is becoming an increasingly serious problem as offshore drilling operations in the subpolar regions become more common. Little information exists on this subject. Extensive observations have been made of icing on the upper structures of moving ships, but the complexity of this problem makes analysis of the results very difficult. Even the generation of water drops in this case involves many factors, such as windspeed, wave direction relative to the bearing of the ship, and size and free-board of the ship. On stationary structures, however, the problem is much simpler, since the major factor in drop generation is whitecaps produced by wind, and no motion of the structure is involved. In the present study, a theoretical calculation was made by combining the data available on the generation of drops by wind with data on the proportion of ice frozen from the collected water. The rate of ice accumulation on stationary structures was calculated using published data. The results were compared with icing measured on board ships. Although the general trend of this calculation indicated parallelism with the onboard measurements, the measured ice accumulation rate on ships needed a 5 to 8 m/s higher windspeed to correspond with the calculated rate for stationary structures.
    Type of Medium: Series available for loan
    Pages: ii, 13 Seiten , Illustrationen
    Series Statement: CRREL Report 84-12
    Language: English
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 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-201-84/11
    In: CRREL Report, 84-11
    Description / Table of Contents: Data obtained from two sets of data buoys either air-dropped or deployed by ship onto the Weddell Sea pack ice during the period from Dec 1978 to Nov 1980 are presented. The buoy data include position, pressure and temperature information and to date represent the most complete combined weather and pack ice drift records for the ice-covered Southern Ocean regions. The buoys tended to drift north initially and then to turn east generally between latitudes 62°S and 64°S. Buoy 1433 turned east farther south at approximately 67°S but at about the same time as buoy 0527, implying that the westerly wind belt was farther south than usual in 1979. The range of air pressures-from about 950 mb to about 1020 mb is typical of the circumpolar low pressure trough in the Southern Hemisphere. All buoys were equipped with an internal or compartment temperature sensor. The 1980 buoys also contained an external air temperature sensor in a ventilated, shielded can at 1-m height. Although differences of 10°C or more between recorded air and compartment temperatures are common, the correlation between the two measured temperatures is generally very good. The compartment temperatures are higher probably because the buoy is radiationally heated. We found that subtracting 3°C from the average daily compartment temperature yielded a good estimate of the average air temperature for any given day. This technique can be used to construct average daily air temperature records for the 1979 buoys which only contained the internal or compartment temperature sensor.
    Type of Medium: Series available for loan
    Pages: v, 21 Seiten , Illustrationen
    Series Statement: CRREL Report 84-11
    Language: English
    Note: CONTENTS Abstract Preface Introduction Methods and instrumentation Results Drift tracks Pressure data Temperature data Discussion Conclusions Literature cited
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 100
    Call number: ZSP-201-84/9
    In: CRREL Report, 84-9
    Description / Table of Contents: This report presents the results of the first 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 I, 222 constant-strain-rate uni-axial compression tests were performed on ice samples from ten multi-year pressure ridges to examine the magnitude and variation of ice strength within and between pressure ridges. A limited number of constant-strain-rate compression and tension tests, constant-load compression tests, and conventional triaxial tests were also performed on ice samples from a multi-year floe to provide preliminary data for developing ice yield criteria and constitutive laws for multi-year sea ice. Data are presented on the strength, failure strain, and modulus of multi-year sea ice under different loading conditions. The statistical variation of ice strength within and between pressure ridges is examined, as well as the effects of ice temperature, porosity, structure, strain rate and confining pressure on the mechanical properties of multi-year sea ice.
    Type of Medium: Series available for loan
    Pages: v, 107 Seiten , Illustrationen
    Series Statement: CRREL Report 84-9
    Language: English
    Note: CONTENTS Abstract Preface Introduction Field Sampling Site selection and description Ice sampling procedures Shipping and storage of ice samples Testing Techniques Multi-year Pressure Ridge Tests Ice description Sampling scheme and test variables Uniaxial compressive strength Residual compressive strength Failure strains Initial tangent modulus Statistical Variations in Ice Strength Differences in strength above and below level ice Sources of the variation in strength Shape of the strength histograms Multi-year Floe Ice Tests Ice description Uniaxial compressive strength Constant-load compression tests Constant-strain-rate tension tests Triaxial tests Conclusions Literature Cited Appendix A: Structural profile of a multi-year pressure ridge core Appendix B: Ridge uniaxial compression test data Appendix C: Structural profile of the continuous multi-year floe core Appendix D: Multi-year floe test data
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...