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
  • Books  (130)
  • Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory  (130)
  • 1980-1984  (130)
  • 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-201-82/33
    In: CRREL Report, 82-33
    Description / Table of Contents: Arctic sea ice is freckled with melt ponds during the ablation season; Antarctic sea ice has few, if any. On the basis of a simple surface heat budget, we investigate the meteorological conditions necessary for the onset of surface melting in an attempt to explain these observations. The low relative humidity associated with the relatively dry winds off the continent and an effective radiation parameter smaller than that characteristic of the Arctic are primarily responsible for the absence of melt features in the Antarctic. Together these require a surface-layer air temperature above 0 C before Antarctic sea ice can melt. A ratio of the bulk transfer coefficients C sub H/C sub E less than 1 also contributes to the dissimilarity in Arctic and Antarctic ablation seasons. The effects of wind speed and of the sea-ice roughness on the absolute values of C sub H and C sub E seem to moderate regional differences, but final assessment of this hypothesis awaits better data, especially from the Antarctic.
    Type of Medium: Series available for loan
    Pages: 16 Seiten , Illustrationen
    Series Statement: CRREL Report 82-33
    Language: English
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 2
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-82/42
    In: CRREL Report, 82-42
    Description / Table of Contents: A high-resolution impulse radar profiling system was evaluated for 1) detecting the existence of sea ice which coring has revealed to exist on the bottom of the Ross Ice Shelf at Site J-9, 2) detecting the preferred horizontal c-axis azi-muthal direction of the sea ice crystals, using the voltage amplitude of the radar reflection from the sea ice bottom, and 3) determining the direction of the currents under an Antarctic ice shelf. A field program was conducted consisting of a surface radar survey on the Ross Ice Shelf at Site J-9 and surface and airborne radar profiling on the McMurdo Ice Shelf. The CRREL impulse radar system, operating at a center frequency of either 80 MHz or 20 MHz, was unable to detect the shelf bottom at Site J-9, which drilling revealed to be 416 m below the snow surface. The radar system was used to profile the McMurdo Ice Shelf both from the snow surface and from the air; a shelf thickness of about 275 m was easily detected. Theoretical considerations indicate that the bulk conductivity of the ice shelf at Site J1-9 was higher than originally anticipated, and this limited the radar sounding depth to about 405 m when operating at a frequency of 20 MHz.
    Type of Medium: Series available for loan
    Pages: iv, 19 Seiten , Illustrationen
    Series Statement: CRREL Report 82-42
    Language: English
    Note: CONTENTS Abstract Introduction Profiling system Theoretical considerations Field program Discussion Literature cited
    Location: AWI Archive
    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-201-82/40
    In: CRREL Report, 82-40
    Description / Table of Contents: The use of explosives to break floating ice sheets is described, and test data are used to develop design curves that predict explosives effects as ice thickness, charge size, and charge depth vary. Application of the curves to practical problems is illustrated by numerical examples. The general features of underwater explosions are reviewed and related to ice blasting. Quasi-static plate theory is considered, and is judged to be inapplicable to explosive cratering of ice plates. The specific energy for optimized ice blasting is found to compare quite favorably with the specific energy of icebreaking ships. All available field data for ice blasting are tabulated in appendices, together with details of the re­gression analyses from which the design curves are generated.
    Type of Medium: Series available for loan
    Pages: iv, 68 Seiten , Illustrationen
    Series Statement: CRREL Report 82-40
    Language: English
    Note: CONTENTS Abstract Preface Introduction General behavior of underwater explosions Regression analysis for ice-blasting data General features of the regression curves Use of the regression curves as design curves for ice blasting Row charges and pattern charges Response of floating ice sheets to underwater explosions Specific energy and “powder factor” Summary and conclusions Literature cited Appendix A: Basic data on ice blasting Appendix B: Scaled input data Appendix C: Initial regression analysis using complete polynomial Appendix D: Regression analysis with two coefficients of the original poly­nomial deleted
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 4
    Call number: ZSP-201-82/37
    In: CRREL Report, 82-37
    Description / Table of Contents: This report presents a Landsat-derived land cover map of the northwest portion of the Arctic National Wildlife Refuge, Alaska. The report is divided into two parts. The first is devoted to the land cover map with detailed descriptions of the mapping methods and legend. The second part is a description of the study area. The classification system used for the maps is an improvement over existing methods of describing tundra vegetation. It is a comprehensive method of nomenclature that consistently applies the same criteria for all vegetation units. It is applicable for large- and small-scale mapping and is suitable for describing vegetation complexes, which are common in the patterned-ground terrain of the Alaskan Arctic. The system is applicable to Landsat-derived land cover classifications. The description of the study area focuses on five primary terrain types: flat thaw-lake plains, hilly coastal plains, foothills, mountainous terrain, and river flood plains. Topography, landforms, soils and vegetation are described for each terrain type. The report also contains area summaries for the Landsat-derived map categories. The area summaries are generated for the five terrain types and for the 89 townships within the study areas. Two land cover maps at 1:250,000 are included.
    Type of Medium: Series available for loan
    Pages: 68 Seiten , Illustrationen, 2 Karten
    Series Statement: CRREL Report 82-37
    Language: English
    Note: CONTENTS Abstract Preface Foreword Introduction A land cover map of the ANWR study area Legend development Mapping method Results Discussion Description of the ANWR study area General description Description of specific terrain types Conclusions Literature cited Appendix A: Descriptions of Landsat land cover categories for ANWR Appendix B: Area summaries Appendix C: Aproximate equivalent units in several systems of land cover, wetland and vegetation classifications used in northern Alaska Appendix D: Soil taxonomy Appendix E: Summary of principal Landsat land cover categories within the terrain types of the ANWR study area
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 5
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-83/19
    In: CRREL Report, 83-19
    Description / Table of Contents: Small-scale laboratory experiments were conducted on model bridge piers in the CRREL test basin. The experiments were performed by pushing model ice sheets against structures and monitoring the ice forces during the ice/structure interaction. The parameters, varied during the test program, were the geometry of the bridge piers and the velocity, thickness, and flexural strength of the ice. The results are presented in the form of ice forces on sloping and vertical structures with different geometries. During ice action on sloping structures, a phenomenon of transition of failure mode from bending to crushing was observed as the ice velocity was steadily increased.
    Type of Medium: Series available for loan
    Pages: 17 Seiten , Illustrationen
    Series Statement: CRREL Report 83-19
    Language: English
    Note: CONTENTS Abstract Preface Introduction Tests Results Ice forces on inclined structures Transition of ice action due to velocity increase Aspect ratio Bridge pier nose geometry Conclusions Literature cited
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 6
    Call number: ZSP-201-83/14
    In: CRREL Report, 83-14
    Description / Table of Contents: An analysis of ice fracture that incorporates dislocation mechanics and linear elastic fracture mechanics is discussed. The derived relationships predict a brittle to ductile transition in polycrystalline ice under tension with a Hall-Petch type dependence of brittle fracture strength on grain size. A uniaxial tensile testing technique, including specimen preparation and loading system design was developed and employed to verify the model. The tensile strength of ice in purely brittle fracture was found to vary with the square root of the reciprocal of grain size, supporting the relationship that the theory suggests. The inherent strength of the ice lattice and the Hall-Petch slope are evaluated and findings discussed in relation to previous results. Monitoring of acoustic emissions was incorporated in the tests, providing insights into the process of microfracture during ice deformation.
    Type of Medium: Series available for loan
    Pages: 43 Seiten , Illustrationen
    Series Statement: CRREL Report 83-14
    Language: English
    Note: CONTENTS Abstract Preface Introduction Background Development of testing technique Test specimens Tensile testing Compression testing Experimental results Tensile tests Compression tests Discussion Conclusions Suggestions for further work Literature cited Appendix A: Additional information on seed grains Appendix B: Thin-sectioning procedure Appendix C: Displacement transducer calibration
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 7
    Call number: ZSP-201-83/22
    In: CRREL Report, 83-22
    Description / Table of Contents: A new experimental method for measuring the soil-water diffusivity of frozen soil under isothermal conditions is introduced. The theoretical justification of the method is presented and the feasibility of the method is demonstrated by experiments conducted using marine-deposited clay. The measured values of the soil-water diffusivity are found comparable to reported experimental data.
    Type of Medium: Series available for loan
    Pages: 13 Seiten , Illustrationen
    Series Statement: CRREL Report 83-22
    Language: English
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 8
    Call number: ZSP-201-83/24
    In: CRREL Report, 83-24
    Description / Table of Contents: Secondary recovery of oil at Prudhoe Bay, Alaska, will involve transporting large quantities of seawater in elevated pipelines across tundra for injection into oil-bearing rock strata. The possibility of a pipeline rupture raises questions concerning the effects of seawater on tundra vegetation and soils. To evaluate the relative sensitivities of different plant communities to seawater, eight sites representing the range of vegetation types along the pipeline route were treated with single, saturating applications of seawater during the summer of 1980. Within a month of the treatment 30 of 37 taxa of shrubs and forbs in the experimental plots developed clear symptoms of stress, while none of the 14 graminoid taxa showed apparent adverse affects. Live vascular plant cover was thus reduced by 89 and 91% in the two dry sites and by 54, 74 and 83% in the three moist sites, respectively. Live(green) bryophyte cover was markedly reduced in the moist experimental sites in 1981. Bryophytes in all but one of the wet-site experimental plots were apparently unaffected by the seawater treatment. Two species of foliose lichens treated with seawater showed marked deterioration in 1981. All other lichen taxa were apparently unaffected by the seawater treatment. The absorption and retention of salts by the soil is inversely related to the soil moisture regime. In the wet sites, conductivities approached prespill levels within about 30 days. In such sites, spills at the experimental volumes are quickly diluted and the salts flushed from the soil. In the dry sites, on the other hand, salts are retained in the soil, apparently concentrating at or near the seasonal thaw line.
    Type of Medium: Series available for loan
    Pages: 43 Seiten , Illustrationen
    Series Statement: CRREL Report 83-24
    Language: English
    Note: CONTENTS Abstract Preface Introduction Methods Site selection and preparation Prespill assessment Seawater application Postspill assessment Enzyme assay and analysis of soil flora Results and discussion Soil-solution conductivities Vascular plant response Cryptogam response Site factors and plant response Soil flora and extracellular soil enzymes Limitations of this study Summary and conclusions Literature cited Appendix: Plant taxa included in this study
    Location: AWI Archive
    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-201-84/24
    In: CRREL Report, 84-24
    Description / Table of Contents: This report describes the growth characteristics and crystalline textures of urea ice sheets which are now used extensively in the Cold Regions Research and Engineering Lab. (CRREL) test basin for modeling sea ice. The aims of the report are to describe the different kinds of crystalline texture encountered in urea ice sheets and to show that even small variations in texture can drastically influence the mechanical behavior of urea ice sheets. Standard petrographic techniques for studying microstructure in thin sections were used on 24 urea ice sheets. These investigations entailed observations of the crystalline texture of the ice (including details of the subgrain structure), grain size measurements, and studies of the nature and extent of urea entrapment and drainage patterns in the ice. Increased knowledge of the factors controlling the crystalline characteristics of urea ice sheets has progressed to the point where test basin researchers at CRREL are now able to fabricate ice sheets with prescribed structures leading to predictable mechanical properties. Originators supplied keywords include: Sea ice, and Mechanical properties.
    Type of Medium: Series available for loan
    Pages: iv, 55 Seiten , Illustrationen
    Series Statement: CRREL Report 84-24
    Language: English
    Note: Contents: Abstract Preface Introduction Objectives Analytical techniques Procedures for growing urea ice sheets Analysis of the crystalline structure of urea ice Characteristics of urea ice Results and discussion Ice sheet no. 1 Ice sheet no. 2 Ice sheet no. 3 Ice sheet no. 4 Ice sheet no. 5 Ice sheet no. 6 Ice sheet no. 7 Ice sheet no. 8 Ice sheet no. 9 Ice sheet no. 10 Ice sheet no. 11 Ice sheet no. 12 Ice sheet no. 13 Ice sheet no. 14 Ice sheet no. 15 Ice sheet no. 16 Ice sheet no. 17 Ice sheet no. 18 Ice sheet no. 19 Ice sheet no. 20 Ice sheet no. 21 Ice sheet no. 22 Ice sheet no. 23 Ice sheet no. 24 Urea concentrations in test tank solution and ice Discussion and conclusions E/σf ratio Thickness of incubation layer Crystal properties Literature cited Appendix A: Thin sections of urea ice sheets
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 10
    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 ...
  • 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-201-84/12
    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 ...
  • 12
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-84/3
    In: CRREL Report, 84-3
    Description / Table of Contents: The results of resistance tests in level ice and broken ice channels are presented for two models of the WTGB 140-fticebreaker at scales of 1:10 and 1:24, respectively. No scale effect on the resistance in level ice could be detected between the two models. From the test results an empirical predictor equation for the full scale ice resistance is derived. Predicted resistance is compared against, and found to be 25 to 40% larger than, available full-scale values estimated from thrust measurements during full-scale trials of the Great Lakes icebreaker Katmai Bay.
    Type of Medium: Series available for loan
    Pages: v, 25 Seiten , Illustrationen
    Series Statement: CRREL Report 84-3
    Language: English
    Note: COTENTS Abstract Preface Nomenclature Introduction Model characteristics and test conditions Ice-hull coefficient of friction Measurements of ice properties Experimental procedures Data acquisition system Test program and procedures for 1:10 model Test program and procedures for 1:24 model Analysis of test results Comparison of test results between 1:10 and 1:24 models Analysis of tests in broken or brash-filled ice channels Analysis of tests in level ice Full-scale prediction of level ice resistance Conclusions Literature cited
    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-201-84/4
    In: CRREL Report, 84-4
    Description / Table of Contents: Ice problems developed in the Sault Ste. Marie, Michigan, portion of the St. Marys River because of winter navigation. Passing ships and natural influences moved ice from Soo Harbor into Little Rapids Cut in sufficient quantities to jam, cause high water in the harbor, and prevent further ship passage. After physical model and engineering studies, two ice booms with a total span of 1375 ft (419 m) with a 250-ft (76-m) navigation opening between were installed at the head of Little Rapids Cut in 1975. A modest field study program on the booms was conducted for the ensuring four winters to determine ice and boom interaction and the effects of ship passages on the system. Forces on some anchors were recorded and supplemental data were taken by local personnel. Several reports have been written about the booms' early operations. This paper presents four-year summary of the main effects of the booms on ice and ship interaction and vice versa. Throughout the four winter seasons, the small quantities of ice lost over and between the booms were manageable. Ships usually passed through the boom without influencing the boom force levels, but at time they brought about large changes. One boom needed strengthening, and artificial islands were added for upstream ice stability. Coast Guard icebreakers were also a necessary part of winter navigation in this area.
    Type of Medium: Series available for loan
    Pages: iv, 18 Seiten , Illustrationen
    Series Statement: CRREL Report 84-4
    Language: English
    Note: CONTENTS Abstract Preface Introduction St. Marys River Ice problems Remedial measures Field studies Highlights, trends, and major findings Modifications to boom Maximum forces Ship traffic Characteristics Effect of boom forces Effect on ice Conclusion Literature cited Appendix A: Ice boom forces
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 14
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-84/5
    In: CRREL Report, 84-5
    Description / Table of Contents: Diatom species composition and relative abundances were determined for ice cores obtained from Weddell Sea pack ice during the October-November 1981 Weddell Polynya Expedition (WEPOLEX). Ice thickness and salinity indicate that the ice was less than one year old. The predominant ice type (70%) was frazil, which has the capacity to mechanically incorporate biological material through nucleation and scavenging. Diatoms were found throughout the length of the cores. Species showed down-core fluctuations in abundance that appeared to be correlated with changes in ice type. Pennate forms were more abundant than centrics, the average ratio being 16:1. Diatom frustules with intact organic material were more abundant (5 billion cells/liter). Differences in species abundances are attributed initially to incorporation of algal cells from a temporally changing water column and subsequently to diatom reproduction within the ice. Scanning electron micrographs illustrating the morphologic characteristics of the predominant species are included.
    Type of Medium: Series available for loan
    Pages: iv, 46 Seiten , Illustrationen
    Series Statement: CRREL Report 84-5
    Language: English
    Note: Contents Abstract Preface Introduction Materials and methods Results Discussion Conclusions Literature cited Appendix A: Taxonomic terms Appendix B: Differences in species composition and abundance in duplicate samples examined under optical and inverted light microscopes Appendix C: Morphologic descriptions and SEM micrographs
    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-201-84/6
    In: CRREL Report, 84-6
    Description / Table of Contents: An expression relating aerosol growth to cold environmental conditions was developed. This was accomplished by solving the diffusion equation with the method of Laplace transformation. The series solution was expressed in terms of the dimensionless parameters K (ratio of vapor density over droplet surface to droplet density), ω (ratio of environmental vapor density at time zero to vapor density over droplet surface), and dimensionless time τ (ratio of product of diffusion coefficient D and time t to square of initial radius of condensation nucleus). To take into account the variation of the vapor density over the surface of an acidic condensation nucleus due to the continuous dilution of the droplet, the solution was obtained by assuming various levels of constant vapor concentration. The final expression [R/R sub o - 1 = 2.4917 x 10 to the minus 18th power) exp(0.0737 θ) (P sub RHS/25) x (100-P sub RHS) τ to the 0.9890 powder] can be used to compute the value of R once the values of initial radius R sub o, relative humidity P sub RH, percent of relative humidity at the droplet surface P sub RHS, and environmental temperature θ are given.
    Type of Medium: Series available for loan
    Pages: vi, 28 Seiten , Illustrationen
    Series Statement: CRREL Report 84-6
    Language: English
    Note: CONTENTS Abstract Preface Nomenclature General background The problem Method of solution Results and discussion Conclusions Literature cited Appendix: Evaluation of rn's in equation 25
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 16
    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 ...
  • 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-201-82/17
    In: CRREL Report, 82-17
    Description / Table of Contents: Seismic P and SH wave refraction experiments at the NATO RSG-11 test site in Munster Nord, Federal Republic of Germany, reveal the presence of a nearly horizontal, three-layer velocity structure. The upper layer, composed of un­consolidated glacial till, is 1 m thick and has P (compressional) and SH (shear-horizontal) wave velocities of 240 and 165 m s-1. The second layer, made up of similar, more compacted material, is 9.5 m thick, with a P wave velocity of 470 m s-1 and an SH wave velocity of 275 m s-1. The third layer, interpreted as the groundwater table, is located at a depth of 10.5 m and has a P wave velocity of 1590 m s-1. The SH wave velocity of this layer is controlled by the matrix material and is the same as that of the second layer. A single, unreversed observation indicated a fourth layer at a depth of about 20 m, but the existence of this layer remains unconfirmed. The observed fundamental mode Love wave dispersion is in agreement with the theoretical dispersion predicted by the refraction velocities. Computed partial derivatives of phase velocity with respect to shear wave velocity show, for the frequencies observed, that the dispersion confirms the thicknesses and velocities of the two upper layers and is not affected by the deeper structure.
    Type of Medium: Series available for loan
    Pages: iv, 33 Seiten , Illustrationen
    Series Statement: CRREL Report 82-17
    Language: English
    Note: CONTENTS Abstract Preface Introduction Refraction experiments Procedure Equipment Results P waves Low velocity zone SH waves Surface wave experiments Summary and discussion Literature cited Appendix A: P wave refraction data Appendix B: SH wave refraction data. Appendix C: Surface wave dispersion calculations
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 18
    Call number: ZSP-201-82/15
    In: CRREL Report, 82-15
    Description / Table of Contents: An experiment is described that demonstrates the balance between the ice and the unfrozen water in a frozen soil as water is removed. Nuclear magnetic resonance (NMR) is used to monitor the unfrozen water content as the soil is dehydrated by a molecular sieve material. Our results show that the unfrozen water content of a Morin clay soil remains constant until the total water content has been reduced to the point where no ice remains in the system. Once the ice is depleted, the unfrozen water content determined by NMR corresponds to the total water content of the soil determined by the weight of water removed by the molecular sieve material. Thus the validity of utilizing NMR in determining unfrozen water contents vs temperature is established.
    Type of Medium: Series available for loan
    Pages: 8 Seiten , Illustrationen
    Series Statement: CRREL Report 82-15
    Language: English
    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-201-82/18
    In: CRREL Report, 82-18
    Description / Table of Contents: Snow and ice control on highways has come to rely heavily on the use of sodium chloride to maintain a trafficable surface for unimpeded movement. Empirical approaches have led to a wide range of application rates, some clearly excessive, but justified on the ground of safety and expediency. The combination of environmental degradation from the huge quantities of salt entering the environment, along with the increased cost of salt itself and the cost of its application have spurred the search for more precise knowledge of the proper amount of salt to apply to a pavement, considering a range of environmental, traffic and chemical parameters. Since controlled tests in the field are extremely difficult to make, a circular test track of three test pavements, dense-graded asphaltic concrete (DGA), open-graded asphaltic concrete (DGA) and portland cement concrete (PCC), was constructed in a coldroom. Natural snow and ice were applied to the pavements and an instrumented slipping wheel was driven over the surfaces to generate frictional forces. These forces were measured and then used to evaluate the response to salt application with time for three test temperatures. OGA had the lowest friction values at a temperature near the freezing point, but higher initial values or more rapidly increasing values than DGA and PCC following salt application at the two lower temperatures. Optimum application rate of salt on PCC and DGA lies between 100 and 300 lb/lane mile (LM), and a higher rate resulted in slight or no improvement in friction. DGA showed anomalous results: lower friction for 300 Ib/LM and higher friction for both 100 and 500 Ib/LM.
    Type of Medium: Series available for loan
    Pages: vi, 55 Seiten , Illustrationen
    Series Statement: CRREL Report 82-18
    Language: English
    Note: CONTENTS Abstract Preface Introduction Objectives Background Approach Influencing factors Field factors Laboratory Laboratory trafficking tests Force measurement and coefficient of friction Test tire slip Surface friction gauge Test procedure British portable tester Experimental results Conclusions Recommendations Literature cited Appendix A. Test pavements Appendix B. Pennsylvania State University field study Appendix C. Rochester Institute of Technology field study
    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-201-82/14
    In: CRREL Report, 82-14
    Description / Table of Contents: A comparative study was made of design criteria and analytical methods for footings and pile foundations on perma­frost employed in U.S.S.R. Design Code SNiP II-18-76 (1977) and U.S. Army Cold Regions Research and Engineering Laboratory Special Report 80-34 developed in the early 1970's by the U.S. Army Corps of Engineers and published in 1980. The absence of adequate constitutive equations for frozen soils and of rigorous solutions of the boundary prob­lems has made it necessary to incorporate (explicitly or implicitly) various safety factors in the foundation analyses. From the review it is concluded that the principal difference between these practices is in the assessment and application of appropriate values of safety factors, which leads to a substantial discrepancy in the dimensions and cost of footings and pile foundations in permafrost.
    Type of Medium: Series available for loan
    Pages: iv, 20 Seiten , Illustrationen
    Series Statement: CRREL Report 82-14
    Language: English
    Note: CONTENTS Abstract Preface Introduction U.S.S.R. system of standards U.S.S.R. Design Code SNiP 11-18-76 (1977) subsoils and foundations on permafrost General regulations Classification of soils Basic regulations for foundation design Analysis of subsoils and foundations Design of foundations for special soil conditions, and appendices SR 80-34 (1980) design and construction of foundations in areas of deep seasonal frost and permafrost General information Foundation design Conclusions Literature cited
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 21
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-82/11
    In: CRREL Report, 82-11
    Description / Table of Contents: The purpose of this investigation was to provide data to be used in evaluating the effects of winter navigation on pro­cesses that cause bank erosion. The specific objectives were to document bank conditions and erosion sites along the rivers, to monitor and compare the amounts of winter and summer bank recession and change, and to estimate the amount of recession that occurred prior to winter navigation. Shoreline conditions and bank recession were documented during field surveys each spring and fall. Bank changes were evaluated by comparison to observations from a previous survey. Aerial photointerpretation was done to estimate the amount of bank recession that occurred prior to winter navigation. Three hundred forty-five miles of river shoreline were surveyed. Banks were eroding along 21.5 miles (6.2%). The common types of bank failures were soil falls (sloughing) and block sliding and slumping. The erosion along approxi­mately 15 miles (70%) of the 21.5 miles was occurring along reaches not bordering winter navigation channels.
    Type of Medium: Series available for loan
    Pages: v, 75 Seiten , Illustrationen
    Series Statement: CRREL Report 82-11
    Language: English
    Note: CONTENTS Abstract Preface Introduction Previous investigations Approach Shoreline conditions Bank changes Bank recession before winter navigation St. Marys River Bank changes Bank recession before winter navigation St. Clair River Bank changes Bank recession before winter navigation Detroit River Bank changes Bank recession before winter navigation St. Lawrence River Bank changes Historical bank recession Summary and conclusions Literature cited Appendix A: St. Marys River Appendix B: St. Clair River Appendix C: Detroit River Appendix D: St. Lawrence River
    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-201-82/7
    In: CRREL Report, 82-7
    In: Charged dislocation in ice, II.
    Description / Table of Contents: The contribution of electrically charged dislocation motion to dielectric relaxation was studied theoretically. Experimentally obtained data on charge density, dislocation density, and segment length and distribution described in Part I of this series were used to calculate dielectric relaxation spectra. The results indicate that the charged dislocation process can produce the observed audio frequency dielectric relaxation as well as the distribution of spectra.
    Type of Medium: Series available for loan
    Pages: iii, 15 Seiten , Illustrationen
    Series Statement: CRREL Report 82-7
    Language: English
    Note: CONTENTS Abstract Preface Introduction Theoretical development of dielectric relaxation due to charged dislocations Numerical calculations for distributed segment length Discussion Conclusions Literature cited Appendix A. Mosotti type catastrophe by charged dislocation processes
    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-201-82/9
    In: CRREL Report, 82-9
    Description / Table of Contents: This study deals with the distribution of forces along the converging boundaries of the Port Huron, Michigan, region where unconsolidated ice in Lake Huron is held against wind and water stresses. An experimental basin was built to induce uniform shear stress on the model ice cover by flowing water beneath the ice. The boundary segments, which held the ice cover in the region, were instrumented to measure force in the normal and tangential directions. The distribution of normal forces along the boundary was compared with as distribution derived by using a theoretical model. An ice control structure (ICS) was installed in the basin and experiments were conducted to measure the forces on the ICS and the ice release through the opening in the ICS during simulated ship passages. The experimental results are presented in a nondimensional form. In addition, the force per unit length on the ICS and the area of ice released through its opening were estimated for the expected wind conditions at the Port Huron site.
    Type of Medium: Series available for loan
    Pages: v, 27 Seiten , Illustrationen
    Series Statement: CRREL Report 82-9
    Language: English
    Note: CONTENTS Abstract Preface List of symbols Introduction Theoretical models Case 1 Case 2 Case 3 Experimental program Experimental facility Scaling factors Experimental results Analysis of wind data for lower Lake Huron Summary and conclusions Release of ice through the opening of an ICS Ice forces on the ice control structure Ice forces on ice control structure from a large unconsolidated ice cover Literature cited Appendix A. Equation for the stress resultants and velocities of the ice cover Appendix B. Monthly summary of wind data at Port Huron
    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-201-82/8
    In: CRREL Report, 82-8
    Description / Table of Contents: A detailed analysis of methods for calculating the thermal conductivity of soils is presented, and trends in the predic­tions of these methods are compared. The influence of changes in the moisture content on the calculated thermal con­ductivity of a soil (at constant dry density) is shown, as is the sensitivity of this calculated value to changes in dry den­sity or in the soil solids’ thermal conductivity. The methods are evaluated to determine the extent of agreement of their predictions with measured values obtained on soils of known composition and properties. The deviations of the predicted values are determined for soils that are unfrozen or frozen, coarse or fine, unsaturated, saturated or dry. The applicability of each of the methods under various conditions is determined and recommendations are made as to the best method for each condition.
    Type of Medium: Series available for loan
    Pages: vi, 90 Seiten , Illustrationen
    Series Statement: CRREL Report 82-8
    Language: English
    Note: CONTENTS Abstract Preface Nomenclature Introduction Analysis of methods for calculating thermal conductivity Introduction Influence of moisture content on thermal conductivity Influence of dry density on thermal conductivity Influence of soil solids’ thermal conductivity Comparison of the various methods Evaluation of methods for calculating thermal conductivity Soils data used for evaluation Computer program Applicability of the methods Discussion and conclusions Applicability to unfrozen soils Applicability to frozen soils Applicability to saturated soils Effect of soil mineral composition Applicability to dry soils Summary of applicability of methods Literature cited Appendix A: Properties of some test soils Appendix B: Comparison of thermal conductivity values computed by the various methods and of their deviations from the values measured
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 25
    Call number: ZSP-201-80/5
    In: CRREL Report, 80-5
    Description / Table of Contents: This research comprised laboratory testing to determine the properties of asphalt-aggregate mixtures containing three grades of asphalt cements, and analyses to project the performance of pavements containing each of the asphalts, in resisting thermally induced distress and traffic-associated distress. From the results it is concluded that only the softest asphalt cement tested (AC 2.5) would perform satisfactorily in a cold climatic zone. The moderately soft (AC 5) and moderately hard (AC 20) asphalt cements showed little susceptibility to thermal cracking in a moderate and a warm climatic zone, respectively. The AC 2.5 and AC 5 asphalts are not recommended for use in warm climates, however, owing to increased susceptibility to rutting under traffic.
    Type of Medium: Series available for loan
    Pages: vi, 55 Seiten , Illustrationen
    Series Statement: CRREL Report 80-5
    Language: English
    Note: CONTENTS Abstract Preface Introduction Research setting Objectives Materials, mixture designs, and tests Materials Mixture design tests Brazil test Resilient modulus test Data analysis Marshall tests Asphalt grade Compactive effort Aggregate type Data analysis Brazil tests Indirect tensile strength Tensile strain Vertical deformation Summary of Brazil test results Data analysis-resilIient modulus. Comparison of mixture susceptibility to temperature cracking General asphalt concrete stiffness Thermal cracking. Influence of asphalt cement properties Summary Comparison of mixture susceptibility to traftic-load-associated distress Stress/strain analysis Fatigue damage analysis Rutting analysis Strength correlations Marshall stability and indirect tensile strength Indirect tensile strength and resilient modulus Summary Summary and conclusions Recapitulation of investigations Summary of results Conclusions Literature cited Appendix A: Asphalt adggregate mixture properties by Marshall method Appendix B: Equations for calculating specimen properties from Brazil tests Appendix C: Calculated displacements, strains and stresses
    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-201-80/28
    In: CRREL Report, 80-28
    Description / Table of Contents: This report investigates the feasibility of clearing ice from the shipping channel of the St. Marys River. Four basic concepts are investigated: disposal under the ice, disposal on top of the ice, slurrying, and rafting. Each technique was found to have application in limited portions of the river with the exception of disposal on top of the adjacent ice sheet which is deemed feasible throughout the river system. Disposal onto the adjacent ice sheet will increase the free stream velocity less than 1.0 ft/s (30.5 cm/s) and raise the water level less than 1.0 ft (0.30 m). Further model and field tests are recommended to validate the findings of this report.
    Type of Medium: Series available for loan
    Pages: ii, 13 Seiten , Illustrationen
    Series Statement: CRREL Report 80-28
    Language: English
    Note: CONTENTS Abstract Preface Introduction The Environment Ice Growth and Accumulation Natural Ice Transport Accumulation Sites 1. Under-ice accumulation 2. Accumulation on top of the ice Evaluation of Ice Disposal Techniques 1. General 2. Disposal by displacement under the remaining ice sheet 3. Disposal by ejection on top of adjacent ice cover 4. Disposal by slurrying 5. Disposal by rafting Conclusions and Recommendations Literature Cited
    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-201-81/13
    In: CRREL Report, 81-13
    Description / Table of Contents: Electrical properties of frozen ground were measured using radio frequency interferometry (RFI) in the very high frequency (VHF) radiowave band. Ice-rich organic silts and sands and gravels of variable ice content were investigated during early April of both 1979 and 1980. Frequencies between 10 and 150 MHz were used with best results obtained between 40 and 100 MHz. Surface impedance and magnetic induction techniques were also used to obtain an independent measure of low frequency resistivity and to obtain a separate control on vertical inhomogeneity. Soil samples were tested for organic and water content. The dielectric constants determined for the ice-rich organic silts ranged from 4.0 to 5.5 while those for the sands and gravels were about 5.1. Dielectric loss was due to d.c. conduction and was very low for the silts but significant for the sands and gravels. The higher values for the sands and gravels were most likely due to the higher concentrations of salt that are reported to exist in the old beach ridges in this region. All the RFI measurements are believed to be indicative of only the first few meters of the ground although the radiowaves could penetrate to tens of meters.
    Type of Medium: Series available for loan
    Pages: iv, 18 Seiten , Illustrationen
    Series Statement: CRREL Report 81-13
    Language: English
    Note: CONTENTS Abstract Preface Introduction Background Objectives and procedures Theory and instrumentation Radio frequency interferometry Case 1: Homogeneous ground model Case 2: Two-layer ground model RFI instrumentation Low frequency methods Point Barrow sites Results and discussion Site 1: Tundra Site 2: Beach ridge Site 3: Marsh Conclusions Literature cited Appendix A: Discussion of low-frequency geophysical methods
    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-201-81/21
    In: CRREL Report, 81-21
    Description / Table of Contents: The reflection of solar radiation by a snow cover in situ and the apparent influence of selected substrates were examined in wavelength bands centered at 0.81, 1.04, 1.10, 1.30, 1.50 and 1.80 micrometers. Substrates included winter wheat, timothy, corn, alfalfa, grass, concrete and subsurface layers of 'crusty' snow and ice. Reasonable qualitative agreement between measurements and theoretical predictions was demonstrated, with indications of quantitative agreement in the definition of a 'semi-infinite depth' of snow cover. It was concluded that ultimate quantitative agreement between theory and measurement will require that an 'optically effective grain size' be defined in terms of physically measuarable dimensions or meteorologically predictable characteristics of the ice crystals composing the snowpack.
    Type of Medium: Series available for loan
    Pages: iii, 17 Seiten , Illustrationen
    Series Statement: CRREL Report 81-21
    Language: English
    Note: CONTENTS Abstract Preface Introduction Experimental method Substrate preparation Experimental configuration Radiometric measurements Snow characterization Reflectance standards Data analysis Reflectance measurements Snow replica analysis Discussion of results Comparative reflectance of various substrates under snow Ablation of a snow cover Reflectance from a very light, fresh snow cover Measurements at angles other than vertical Reflectance from substrates Concluding observations Literature cited
    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-201-81/16
    In: CRREL Report, 81-16
    Description / Table of Contents: An air-transportable shelter designed and built at CRREL for use in cold regions underwent testing in Hanover, New Hampshire, and Ft. Greely, Alaska. The shelter demonstrated some of its capabilities for mobility by being towed for more than 60 miles behind various vehicles and by being transported on a C-130 cargo airplane, a CH-47 helicopter, and a trailer truck. The shelter proved to be very easy for a crew of two to four to set up in all weather conditions including -40 F cold. However, the gasoline-powered generator, which was a source for space heat as well as electricity, functioned very poorly. Overall, the prototype successfully demonstrated qualities of self-reliance, ease of operation and thermal efficiency.
    Type of Medium: Series available for loan
    Pages: v, 20 Seiten , Illustrationen
    Series Statement: CRREL Report 81-16
    Language: English
    Note: CONTENTS Abstract Preface Metric conversion factors Summary Introduction Description of shelter Test procedures and results Mobility Ease of erecting and striking Therinal efficiency and performance Heat output Electrical system Habitation Safety features Water system Shelter reliability Structure Performance of other shelters Conclusions Future studies 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-201-81/17
    In: CRREL Report, 81-17
    Description / Table of Contents: Environmental conditions are described for the continental shelf of the western Arctic, and for the shelf of Labrador and Newfoundland. Special emphasis is given to the gouging of bottom sediments by ice pressure ridges and icebergs, and an approach to systematic risk analysis is outlined. Protection os subsea pipelines and cables by trenching and direct embedment is discussed, touching on burial depth, degree of protection, and environmental impact. Conventional land techniques can be adapted for trenching across the beach and through the shallows, but in deeper water special equipment is required. The devices discussed include hydraulic dredges, submarine dredges, plows, rippers, water jets, disc saws and wheel ditchers, ladder trenchers and chain saws, routers and slot millers, ladder dredges, vibratory and percussive machines, and blasting systems. Consideration is given to the relative merits of working with seabed vehicles, or alternatively with direct surface support from vessels or from the sea ice
    Type of Medium: Series available for loan
    Pages: 38 Seiten , Illustrationen
    Series Statement: CRREL Report 81-17
    Language: English
    Note: CONTENTS Abstract Preface Introduction The western Arctic of North America The continental shelf of Newfoundland and Labrador Burial depth for pipes and cables Degree of protection offered by burial Environmental impact Trenching the beach and the shallows in the western Arctic Trenching beyond the shallows Suction, or hydraulic, dredging Bottom-t raveling cutterhead dredges Plows Rippers Water jets Subsea disc saws and wheel ditchers Subsea ladder trenchers and chain saws Subsea routers and slot millers Bucket ladder trenchers Vibratory and percussive devices Hard rock excavation under water Control and monitoring of subsea machines Vessels and vehicles Trenching from the sea ice Costs of subsea trenching Reference Appendix: Description of waters off Alaska and Newfoundland
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 31
    Call number: ZSP-201-81/1
    In: CRREL Report, 81-01
    Description / Table of Contents: Abstract: The formation of ice jams and their meteorological indicators were studied in detail for the winters of 1975-76, 1976-77 and 1977-78 on the Ottauquechee River at and east of Woodstock, Vermont. Meteorological data are presented for nearby National Weather Service Co-Operative Stations as well as for CRREL sites on the Ottauquechee River. The severity of each winter is discussed, as are the effects of a heavy rainfall on a high water equivalent snow cover. The resultant runoff and subsequent ice jamming that occurs is discussed. Continuous monitoring of water temperature before, during and immediately after an ice cover formed on the river during the winter of 1977-78 is included. The report includes a section on warm sewer outfall effects on the ice at and below a municipal treatment plant. Retrieved data will assist in future modeling studies to help predict ice formation, growth, decay and jamming of river ice covers.
    Type of Medium: Series available for loan
    Pages: iv, 26 Seiten , Illustrationen
    Series Statement: CRREL Report 81-01
    Language: English
    Note: CONTENTS Abstract Preface Introduction Meteorological data retrieval and measurements Meteorological effects on river ice cover Winter 1975-76 Winter 1976-77 Winter 1977-78 Analysis of ice formation and decay Mechanism of ice formation Ice growth and decay on the Ottauquechee River, 1975-76, 1976-77, 1977-78 Influence of warm sewage effluent on river water temperatures and ice conditions Conclusions Literature cited Appendix A: Climatological observations Appendix B: Ice conditions, field remarks and pertinent photography
    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-201-81/3
    In: CRREL Report, 81- 3
    Description / Table of Contents: Abstract: A 1:24 scale hydraulic model study of water intake under frazil ice conditions is presented. The intake, located 9 m below the surface of the St. Lawrence River in Massena, New York,has a through flow of 0.14 m^3/s. The model study, conducted in the refrigerated flume facility of the U.S. Army Cold Regions Research and Engineering Laboratory, investigated methods of minimizing the frazil ice blockage on the intake. Two protective structures were modeled and the relative benefits of each are presented. The additional cross-sectional area provided by the protective structures lowered the vertical velocity component of the intake water to 0.0027 m/s. At this velocity the buoyant force acting on the frazil ice particle is larger than the downward drag force, causing the particle to rise. The results demonstrate that under certain low flow conditions a protective structure can minimize frazil ice blockage problems.
    Type of Medium: Series available for loan
    Pages: 11 Seiten , Illustrationen
    Series Statement: CRREL Report 81-03
    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-201-81/2
    In: CRREL Report, 81-2
    Description / Table of Contents: Abstract: Many hyperbolic reflections have been observed on marine seismic records obtained during oil exploration in the Beaufort Sea, and on USGS seismic sub-bottom profiles from the Prudhoe Bay vicinity. A hyperbolic projection system was designed to rapidly measure seismic velocities from the curves on the records. The velocities observed were approximately the velocity of sound in water. The hyperbolic signals also showed dispersion properties similar to acoustic normal modes in shallow water. These observations indicate that the signals responsible for the hyperbolic reflections propagate as normal modes within the water layer, with very limited penetration of the seabed. Determinations of the dominant frequency of these signals indicate that the penetration into the seabed has a characteristic attenuation depth (skin depth) of about 1.5 m for the sub-bottom profiles and 12 m for the marine records. It therefore appears that some hyperbolic reflections may be generated by variations in materials that occur near the seabed. There is some evidence of linearity of the anomalies, possibly related to sediment-filled or open ice gouges, or other changes in material properties at shallow depths.
    Type of Medium: Series available for loan
    Pages: iv, 16 Seiten , Illustrationen
    Series Statement: CRREL Report 81-2
    Language: English
    Note: CONTENTS Abstract Preface Introduction Methods of analysis Marine seismic records Seismic sub-bottom profiles Results and discussion Distribution of hyperbolic reflections Hyperbolas on oil exploration records Hyperbolas on sub-bottom profiles Conclusions Literature cited Appendix A: Hyperbola projector
    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-201-82/24
    In: CRREL Report, 82-24
    Description / Table of Contents: Velocity data derived from petroleum industry seismic records from Harrison Bay show that high-velocity material ( or = 2 km/s) interpreted to be ice-bonded permafrost is common. In the eastern part of the bay, the depth to high velocity material increases and velocity decreases in an orderly manner with increasing distance from shore until the layer is no longer apparent. The western part of the bay is less orderly, possibly reflecting a different geological and thermal history. This western part may be an inundated section of the low coastal plain characterized by the region north of Teshekpuk Lake, and could have contained deep thaw lakes, creating low velocity zones. Along some seismic lines, the high-velocity material extends approximately 25 km offshore. Two anomalies have been found which could be associated with rapidly degrading permafrost. One is strong attenuation, which was interpreted as an indication of gas in the shallow deposits. The other is the presence of considerable seismic noise, including identifiable small seismic events. The origin of this noise has not been positively established, and it is proposed that it may indicate that some movement is occurring in the sediments due to thaw.
    Type of Medium: Series available for loan
    Pages: 65 Seiten , Illustrationen
    Series Statement: CRREL Report 82-24
    Language: English
    Note: CONTENTS Abstract Preface Introduction Methods Reading records Refractions Reflections Rayleigh waves Spatial resolution Anomalies Results and discussion Seismic velocity distribution Attenuation Low-level natural seismicity Summary Literature cited Appendix A: Error estimates Appendix B: Velocity profiles Appendix C: Seismic cross sections
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 35
    Call number: ZSP-201-82/26
    In: CRREL Report, 82-26
    Description / Table of Contents: The Caribou-Poker Creeks Research Watershed is a small (101.5-sq km) drainage basin located 48 km northwest of Fairbanks, Alaska. Elevations within the watershed range from 210 to 826 m, and approximately 28% of its area is underlain by permafrost. Climatic differences between the watershed and Fairbanks are primarily due to the higher elevation of the watershed. Generally the watershed climatic sites are warmer in winter and cooler in summer than Fairbanks. Within the watershed the greatest temperature contrasts exist in winter, when the valley-bottom sites are beneath the regional air temperature inversion, and the higher sites are above it. From May through September the total precipitation averages 270 mm, 1.47 times that received at Fairbanks. The annual precipitation is about 1.7 times that of Fairbanks. The historical precipitation record at Fairbanks indicates that summer precipitation was below the long-term normal in eight of the eleven years of watershed measurements (1969-1980); no climatic extremes occurred during this period. An analysis of annual streamflow data showed an inconsistency of baseflow recessions from year to year. The runoff-rainfall ratio for individual summer storms averaged 0.35 for Caribou Creek. Comparisons of spot discharge measurements of predominantly permafrost and non-permafrost subwatersheds showed that permafrost-dominated watersheds have a much flashier response to precipitation than non-permafrost watersheds. A comparison of the annual flow distribution of the watershed indicated that Caribou Creek has lower summer and higher winter discharges per unit area than the Chena or Salcha Rivers.
    Type of Medium: Series available for loan
    Pages: 42 Seiten , Illustrationen
    Series Statement: CRREL Report 82-26
    Language: English
    Note: CONTENTS Abstract Preface Introduction Setting Geology and soils Vegetation Climate Air temperature Precipitation Hydrology Annual and monthly runoff Individual storms Baseflow recessions Spatial flow variability Temporal flow variability Summary and conclusions Literature cited Appendix A: Station histories
    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-201-82/29
    In: CRREL Report, 82-29
    Description / Table of Contents: Ice grains in a snow cover with a low temperature gradient assume a well-rounded equilibrium form. However, at temperature gradients of 0.1 to 0.2 C/cm (depending somewhat on temperature and snow density), the rounded grains recrystallize into a faceted kinetic growth form. The large temperature gradient must play a decisive role in moving the vapor fast enough to sustain the rapid growth rate associated with the kinetic growth form. Once the large temperature gradient is removed, the grains recrystallize back to the equilibrium form. the recrystallization occurs in either direction without a change in bulk density. The growth of faceted crystals begins at the warmer base of the snow cover where the excess vapor pressure is largest. A transition between the overlying rounded grains moves upward in time. Faceted crystals also grow just below crusts of reduced permeability, where the increased vapor accumulation can sustain the excess vapor pressure neded for kinetic growth. The heat and vapor flows are described using a model based on thermodynamic equilibrium. The temperature distribution is shown to be quasi-linear at steady state in homogeneous snow. The recrystallization of the snow is modeled using the rounded grains as sources and the faceted grains as sinks. In the future this model should be extended to account for different temperatures among the sources and sinks.
    Type of Medium: Series available for loan
    Pages: 27 Seiten , Illustrationen
    Series Statement: CRREL Report 82-29
    Language: English
    Note: Contents: Abstract Preface Introduction Vapor flow Temperature profile Crystal growth rates Equilibirum versus kinetic growth forms of snow crystals Discussion Summary Literature cited
    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-201-82/31
    In: CRREL Report, 82-31
    Description / Table of Contents: Information on sea ice conditions in the Bering Strait and the icefoot formation around Fairway Rock, located in the strait, is presented. Cross-sectional profiles of Fairway Rock and the relief of the icefoot are given along with theoretical analyses of the possible forces active during icefoot formation. It is shown that the ice cover most likely fails in flexure as opposed to crushing or buckling, as the former requires less force. Field observations reveal that the Fairway Rock icefoot is massive, with ridges up to 15 m high, a seaward face only 20 degrees from vertical, and interior ridge slopes averaging 33 degrees. The icefoot is believed to be grounded and its width ranges from less than 10 to over 100 m.
    Type of Medium: Series available for loan
    Pages: 44 Seiten , Illustrationen
    Series Statement: CRREL Report 82-31
    Language: English
    Note: CONTENTS Abstract Preface Introduction Bering Strait Field reconnaissance Estimation of ice forces on Fairway Rock 1. Creep deformation 2. Crushing failure 3. Flexural failure 4. Forces required to form floating or grounded pressure ridges along therock or to pile ice on the beaches 5. Buckling failure Driving forces Angle of internal friction of sea ice Summary Literature cited Appendix A: April 1982 field observations at Fairway Rock
    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-201-82/34
    In: CRREL Report, 82-34
    Description / Table of Contents: The ice discharge through an opening in an ice control structure was documented to be a function of the floe size, ice type, ice floe conditions and vessel direction. The model data for the average ice discharge per vessel transit scaled to prototype values compared favorably with data taken at the St. Marys River ice control structure (ICS). The model results of the force measurements were also consistent with data taken at the St. Marys ICS. The dynamic loading conditions were independent of vessel direction. The dynamic loading to the structure using 3 types of ice (plastic, natural and urea-doped) showed a considerable difference in their means and standard deviations. The urea-doped ice was evaluated for dynamic loading conditions, and reasonable peak values of 3 to 5 times the mean load at each measuring position were recorded, independent of vessel direction. It appears that synthetic random ice floes may be used in model studies where ice discharge through an opening in a structure needs to be documented. This study shows the synthetic random ice floe discharge to fall reasonably within the values obtained for natural ice discharge for both rafted and non-rafted ice fields above the ICS. However, the question of whether synthetic ice can be used for analyzing force distributions and dynamic force loading criteria cannot be fully answered at this time because the load distributions of the synthetic and natural floes appear to differ.
    Type of Medium: Series available for loan
    Pages: 68 Seiten , Illustrationen
    Series Statement: CRREL Report 82-34
    Language: English
    Note: CONTENTS Abstract Preface Introduction Scope of work Ice discharge from Lake Huron into St. Clair River Water velocity profiles at Port Huron Ice conditions Physical model Basis for selection Description Instrumentation Model ice control structure Open water calibration Open water tests Experimental procedures and techniques Ice cover calibration Ice control structure orientation Analysis of ice discharge due to ship transits Natural ice Synthetic ice Forces on the ice control structure Static measurements Dynamic force measurements Potential additional shear stresses Anticipated ice conditions with ICS Conclusions Literature cited Appendix A. Application of model results Appendix B. Suggested additional studies Appendix C. Derivation of ice discharge
    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-201-83/9
    In: CRREL Report, 83-9
    Description / Table of Contents: Recent observations of shore ice pile-up and ride-up along the coast of the Alaska Beaufort Sea are presented. Information is given to show that sea ice movement on shore has overridden steep coastal bluffs and has thrust inland over 150 m, gouging into and pushing up mounds of beach sand, gravel, boulders and peat and, inland, the tundra material. The resulting ice scar morphology was found to remain for tens of years. Onshore ice movements up to 20 m are relatively common, but those over 100 m are very infrequent. Spring is a dangerous time, when sea ice melts away from the shore, allowing ice to move freely. Under this condition, driving stresses of less than 100 kPa can push thick sea ice onto the land.
    Type of Medium: Series available for loan
    Pages: v, 59 Seiten , Illustrationen
    Series Statement: CRREL Report 83-9
    Language: English
    Note: Contents Abstract Preface Introduction Winter 1979-80 observations Winter 1980-81 and summer 1981 observations Winter 1981-82 and summer 1982 observations Old ice ride-up features Discussion Literature cited Appendix A. The boulder rampart and rock littered shore west of Konganevik Pt. Appendix B. Site location maps
    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-201-83/6
    In: CRREL Report, 83-6
    Description / Table of Contents: During the austral summers of 1976-77 and 1978-79, several ice cores were taken from the McMurdo Ice Shelf brine zone to investigate its thermal, physical and chemical properties. This brine zone consists of a series of super-imposed brine layers (waves) that originate at the seaward edge of the ice shelf and migrate at various rates, depending upon their age and position in the ice shelf. The brine in these layers becomes increasingly concentrated as the waves migrate inland through the permeable ice shelf firn. Chemical analyses of brine samples from the youngest (uppermost) brine wave show that it contains sea salts in normal seawater proportions. Further inland, deeper and older brine layers, though highly saline (S 〉 200 ‰), are severely depleted in SO2-4 with the SO2-4/Na+ ratio being an order of magnitude less than that of normal seawater. Analyses of Na+, K+, Ca2+, Mg2+, SO2-4 and CI-, together with solubility and temperature considerations, show that the sulfate depletion is due to selective precipitation of mirabilite, Na2SO4*10H2O. The location of the inland boundary of brine penetration is closely related to the depth at which the brine en-counters the firn/ice transition. However, a small but measurable migration of brine is still occurring in otherwise impermeable ice; this is attributed to eutectic dissolution of the ice by concentrated brine as it moves into deeper and warmer parts of the McMurdo Ice Shelf.
    Type of Medium: Series available for loan
    Pages: iii, 16 Seiten , Illustrationen
    Series Statement: CRREL Report 83-6
    Language: English
    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-201-83/2
    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 ...
  • 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-201-82/36
    In: CRREL Report, 82-36
    Description / Table of Contents: Camp construction and drilling activities in 1950 at the East Oumalik drill site in northern Alaska caused extensive degradation of ice-rich, perennially frozen silt and irreversible modification of the upland terrain. In a study of the long-term degradational effects at this site, the near-surface geology was defined by drilling and coring 76 holes (maximum depth of 34 m) in disturbed and undisturbed areas and by laboratory analyses of these cores. Terrain disturbances, including bulldozed roads and excavations, camp structures and off-road vehicle trails, were found to have severely disrupted the site's thermal regime. This led to a thickening of the active layer, melting of the ground ice, thaw subsidence and thaw consolidation of the sediments. Slumps, sediment gravity flows and collapse of materials on slopes bounding thaw depressions expanded the degradation laterally, with thermal and hydraulic erosion removing materials as the depressions widened and deepened with time. Degradational processes became less active after thawed sediments thickened sufficiently to slow the increase in the depth of thaw and permit slope stabilization. The site's terrain is now irregular and hummocky with numerous depressions. Seasonal thaw depths are deeper in disturbed areas than in undisturbed areas and reflect the new moisture conditions and morphology. The severity of disturbance is much greater at East Oumalik than at another old drill site, Fish Creek. The difference results primarily from differences in the physical properties of the sediments, including the quantity and distribution of ground ice.
    Type of Medium: Series available for loan
    Pages: 42 Seiten , Illustrationen
    Series Statement: CRREL Report 82-36
    Language: English
    Note: CONTENTS Abstract Preface Summary Introduction Methodology Geologic setting Camp construction and occupation Types of disturbance Degradational processes and the effective area of impact Areal effects of disturbance Topography Groundwater, surface water and drainage Sediment properties and near-surface stratigraphy Surficial processes Depth of thaw Comparison to Fish Creek Discussion and conclusions Literature cited
    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-201-83/18
    In: CRREL Report, 83-18
    Description / Table of Contents: An evaluation of an impulse radar system for detecting cavities under concrete pavement is discussed, and field results are presented. It was found that a dual antenna mode of surveying was ideal for void detection. In this mode one antenna operated in a transceive mode and a second, offset from the first, operated in a receive-only mode. This arrangement allowed a refraction-type profile survey to be performed, which enabled subpavement voids to be easily detected. Field trails were held at Plattsburgh Air Force Base, where 28 cavities were detected and mapped. Drilling of holes verified that a cavity existed and allowed cavity depth to be measured. The cavities varied from 1.5 in. to 23 in, depth and were up to 20 ft. long.
    Type of Medium: Series available for loan
    Pages: 49 Seiten , Illustrationen
    Series Statement: CRREL Report 83-18
    Language: English
    Note: CONTENTS Abstract Preface Introduction Plattsburgh Air Force Base Radar sounding system Survey procedure Cavity inspection Radar cavity detection test Radar profile results Falling-weight deflectometer tests Discussion and conclusions 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-201-83/12
    In: CRREL Report, 83-12
    Description / Table of Contents: This paper documents the development and verification of two finite difference models that solve the general two-dimensional form of the heat conduction equation, using the alternative-direction implicit method. Both can handle convective, constant flux, specified temperature and semi-infinite boundaries. The conducting medium may be composed of many materials. The first program, ADI, solves for the case where no change of state occurs. ADIPC solves for case where a freeze/thaw change of phase may occur, using the apparent heat capacity method. Both models are verified by comparison to analytical results.
    Type of Medium: Series available for loan
    Pages: 74 Seiten , Illustrationen
    Series Statement: CRREL Report 83-12
    Language: English
    Note: CONTENTS Abstract Preface Introduction Finite differences applied to heat transfer Heat conduction equation Boundary conditions Phase change Computer program ADDATA, the data subroutine TRIDIG, the matrix solver ISOTHM, the isotherm finider ADI, main program ADEPC, main program Verification of ADI Comparison of ADI with analytical results Comparison of ADI with experimental results Verification of ADIPC Comparison of ADIPC with analytical results-the Neumann solution Comparison of ADIPC with analytical results-two-dimensional phase change verification User instruction for ADI User instruction for ADIPC Conclusions Literature cited Appendix A. Program INFSUM and sample input and output for program ADI Appendix B. Program ADIPC and sample input and output
    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-201-83/17
    In: CRREL Report, 83-17
    Description / Table of Contents: A sea ice model was applied to the East Greenland Sea to examine a 60-day ice advance period beginning 1 October 1979. This investigation compares model results using driving geostrophic wind fields derived from three sources. Winds calculated from sea-level pressures obtained from the National Weather Service's operational analysis system resulted in strong velocities concentrated in a narrow band adjacent to the Greenland coast, with moderate velocities elsewhere. The model showed excessive ice transport and thickness build-ups in the coastal region. The extreme pressure gradient parallel to the coast resulted partially from a pressure reduction procedure that was applied to the terrain-following sigma coordinate system to obtain sea-level pressures. Additional sea-level pressure fields were obtained from an independent optimal interpolation analysis that merged FGGE buoys drifting in the Arctic basin with high latitude land stations and from manual digitization of the NWS hand-analyzed Northern Hemisphere Surface Charts. Modeling results using winds from both of these fields agreed favorably.
    Type of Medium: Series available for loan
    Pages: 19 Seiten , Illustrationen
    Series Statement: CRREL Report 83-17
    Language: English
    Note: CONTENTS Abstract Preface Introduction Description of study Model results The problem Conclusions Literature cited
    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-201-83/26
    In: CRREL Report, 83-26
    Description / Table of Contents: Ice accreted on high-speed rotors operating in supercooled fog can be thrown off by centrifugal force, creating severe unbalance and dangerous projectiles. A simple force balance analysis indicates that the strength of accreted ice and its adhesive strength can be obtained by measuring the thickness of the accretion, the location of the separation, the rotor speed, and the density. Such an analysis was applied to field and laboratory observations of self-shedding events. The results agree reasonably well with other observations.
    Type of Medium: Series available for loan
    Pages: 13 Seiten , Illustrationen
    Series Statement: CRREL Report 83-26
    Language: English
    Location: AWI Archive
    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-201-84/17
    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 ...
  • 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-201-84/15
    In: CRREL Report, 84-15
    Description / Table of Contents: Measurements of meltwater pH from annual layers of South Pole firn and ice samples ranging in age from 40 to 2000 years B.P. show that precipitation at this remote site has a higher natural acidity than that expected from atmospheric equilibrium with CO2. The average pH of deaerated (CO2-free) samples was 5.64 + or - 0.08, while air-equilibrated samples averaged 5.37 + or - 0.008, a pH that is about a factor of two more acidic than the expected background pH of 5.65. The observed 'excess' acidity can be accounted for by natural SO4(2)- and NO(3)- levels in the samples probably originating from non-anthropogenic H2SO4 and HNO3. Because of the presence of these naturally occurring acids in South Pole precipitation, a pH of 5.4 is considered a more representative baseline reference pH for acid precipitation studies.
    Type of Medium: Series available for loan
    Pages: ii, 12 Seiten , Illustrationen
    Series Statement: CRREL Report 84-15
    Language: English
    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-201-84/11
    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 ...
  • 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-201-82/30
    In: CRREL Report, 82-30
    Description / Table of Contents: Equations are developed that can be used to determine the amount of gas present in sea ice from measurements of the bulk ice density, salinity and temperature in the temperature range o f-2 to -30°C. Conversely these relationships can be used to give the density of sea ice as a function of its temperature and salinity, considering both the presence of gas and of solid salts in the ice. Equations are also given that allow the calculation of the gas and brine volumes in the ice at temperatures other than that at which the bulk density was determined.
    Type of Medium: Series available for loan
    Pages: 13 Seiten , Illustrationen
    Series Statement: CRREL Report 82-30
    Language: English
    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-201-82/32
    In: CRREL Report, 82-32
    Description / Table of Contents: Low-frequency (10 Hz) volcanic earthquakes originate at a wide range of depths and occur before, during, and after magmatic eruptions. The characteristics of these earthquakes suggest that they are not typical tectonic events. Physically analogous processes occur in hydraulic fracturing of rock formations, low-frequency icequakes in temperate glaciers, and autoresonance in hydroelectric power stations. We propose that unsteady fluid flow in volcanic conduits is the common source mechanism of low-frequency volcanic earthquakes (tremor). The fluid dynamic source mechanism explains low-frequency earthquakes of arbitrary duration, magnitude, and depth of origin, as unsteady flow is independent of physical properties of the fluid and conduit. Fluid transients occur in both low-viscosity gases and high-viscosity liquids. A fluid transient analysis can be formulated as generally as is warranted by knowledge of the composition and physical properties of the fluid, material properties, geometry and roughness of the conduit, and boundary conditions. To demonstrate the analytical potential of the fluid dynamic theory, we consider a single-phase fluid, a melt of Mount Hood andeside at 1250 deg C, in which significant pressure and velocity variations occur only in the longitudinal direction.
    Type of Medium: Series available for loan
    Pages: 15 Seiten , Illustrationen
    Series Statement: CRREL Report 82-32
    Language: English
    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-201-83/8
    In: CRREL Report, 83-8
    Description / Table of Contents: In the course of model tests with urea-doped ice in the CRREL Ice Engineering Facility test basin, the growth process and the physical and mechanical properties of the model ice were investigated. The parameters which were varied were: urea concentration in the tank water, air temperature during growth, growth duration, and tempering time. Uniformity of ice thickness and ice mechanical properties over the whole tank area were found to be satisfactory. The structure of the urea-doped ice was found to be similar to that of the ice except for a relatively thick incubation layer over a dendritic bottom layer. Empirical relationships were established between: ice thickness and negative degree-hours; mechanical properties and growth temperature, urea concentration, and ice thickness; and reduction in mechanical properties and tempting time. The results of the study are presented in charts which permit reliable scheduling of model tests with required ice thickness and ice flexural strength.
    Type of Medium: Series available for loan
    Pages: vii, 53 Seiten , Illustrationen
    Series Statement: CRREL Report 83-8
    Language: English
    Note: CONTENTS Abstract Preface Nomenclature Introduction Experimental facility and procedures Ice test basin Ice growth procedure Measurements Ice growth and structure Ice thickness distribution Ice growth during freeze-up Ice growth during warm-up Structure of urea-doped ice Mechanical properties of urea-doped ice Introductory remarks Model of a two-layer elastic material Properties of urea-doped ice during freeze-up Properties of urea-doped ice during warm-up Applications to test program scheduling Summary and conclusions Literature cited Appendix A: Results of ice thickness measurements for various growth conditions Appendix B: Properties of untempered ice Appendix C: Properties of tempered ice
    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-201-83/5
    In: CRREL Report, 83-5
    Description / Table of Contents: This report presents the results of dynamic ice-structure interaction model tests conducted at the CRREL Ice Engineering Facility. A flexible, single-pile, bottom-founded offshore structure was simulated by a test pile with about a one-to-ten scale ratio. Urea (instead of sodium chloride) was used as dopant to scale down the ice properties, resulting in good model ice properties. Six ice fields were frozen and 18 tests carried out. In all cases distinctive dynamic ice structure interaction vibrations appeared, from which abundant data were collected. In tests with linear ice velocity sweep, sawtooth-shaped ice force fluctuations occurred first. With increasing velocity the natural modes of the test pile were excited, and shifts from one mode to another occurred. The maximum ice force values appeared mostly with low loading rates, but high forces appeared random'y at high ice velocities. As a general trend, ice force maximums, averages and standard deviations decreased with increasing ice velocities. The aspect ratio effect of the ice force in continuous crushing follows the same dependence as in static loadings. The frequency of observed ice forces is strongly dominated by the natural modes of the structure. Dynamically unstable natural modes tend to make the developing ice force frequencies the same as the natural frequencies. Otherwise the resulting frequency depends directly on structural stiffness and ice velocity and inversely on the ice force range. During vibrations the displacement rates of the structure overcome the velocity of ice, making low loading rates and hence high ice forces possible. During crushing, ice induces both positive and negative damping.
    Type of Medium: Series available for loan
    Pages: iv, 53 Seiten , Illustrationen
    Series Statement: CRREL Report 83-5
    Language: English
    Note: CONTENTS Abstract Preface Introduction Test arrangements Ice properties Crushing patterns Maximum ice force vs velocity Dynamic aspect ratio effect and crushing strength Measured ice force frequencies Calculated ice force frequencies Accelerations, velocities and displacements Damping Ice-induced negative damping Limit cycles Buckling load Conclusions Literature cited
    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-201-83/1
    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 ...
  • 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-201-82/43
    In: CRREL Report, 82-43
    Description / Table of Contents: The radar signatures of ice wedges and wedge-like structures have been investigated for a variety of soil conditions. The radar used for this study emitted short sinusoidal pulses of about 10-ns duration with an approximate center frequency of 150 MHz. Most of the ice wedges existed at depths of about 1 m in a variety of silty and sandy soils with both frozen and thawed active layers. The position of the wedges was usually identified from corresponding surface features. An artificial ice wedge in coarse-grained alluvium was also profiled as well as wedge-like structures of fine silt in a coarse-grained glacial outwash. All wedges and wedge-like structures produced a hyperbolic reflection profile except when an active layer of thawed, saturated silt was present which eliminated returns from the wedges. The peaks of the hyper-bolas were sometimes masked by reflections from the permafrost table or other material interfaces, and multiple hyperbolas occurred at some sites. The dielectric constant of the host medium was often calculated from the linear portions of the hyperbolas and the results were verified by laboratory time domain reflectometry measurements per-formed on field samples. In some cases, hyperbolic profiles originated at several meters depth suggesting that deep ice wedges could be detected in areas of cold permafrost.
    Type of Medium: Series available for loan
    Pages: iv, 19 Seiten , Illustrationen
    Series Statement: CRREL Report 82-43
    Language: English
    Note: CONTENTS Abstract Preface Introduction Background Objectives and procedures Equipment used Radar TDR Definitions Massive ice Results Artificial wedge: Norwich, Vermont Ice wedges in sand: Fish Creek, Alaska Ice wedges: Prudhoe Bay, Alaska Ice wedges under thawed fine-grained soils: North Slope, Alaska Wedge-like soil structures: Ft. Greely, Alaska TDR measurements Summary and concluding remarks Literature cited Appendix A: Brief discussion of dispersion
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 56
    Call number: ZSP-201-82/39
    In: CRREL Report, 82-39
    Description / Table of Contents: Observations of a 4.4-m-high brine step in the McMurdo Ice Shelf, Antarctica, show that it has migrated about 1.2 km in 4 years. The present brine wave is overriding an older brine-soaked layer. This migration is proof of the dynamic nature of the step, which is the leading edge of a brine wave that originated at the shelf edge after a major break-out of the McMurdo Ice Shelf. The inland boundary of brine penetration is characterized by a series of descending steps that are believed to represent terminal positions of separate intrusions of brine of similar origin. The inland boundary of brine percolation is probably controlled largely by the depth at which brine encounters the firn/ ice transition (43 m). However, this boundary is not fixed by permeability considerations alone, since measurable movement of brine is still occurring at the inland boundary. Freeze-fractionation of the seawater as it migrates throught the ice shelf preferentially precipitates virtually all sodium sulfate, and concomitant removal of water by freezing in the pore spaces of the infiltrated firm produces residual brines approximately six times more concentrated than the original seawater.
    Type of Medium: Series available for loan
    Pages: v, 35 Seiten , Illustrationen
    Series Statement: CRREL Report 82-39
    Language: English
    Note: CONTENTS Abstract Preface Introduction Objectives Analytical techniques Radio echo profiling Core drilling Results and discussion Brine infiltration survey Brine layer steps Brine infiltration characteristics Brine infiltration mechanisms at inland boundary Confirmation of brine depths by drilling Density and temperature profiles Ice shelf freeboard Brine upwelling Brine chemistry Conclusions Literature cited
    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-201-83/13
    In: CRREL Report, 83-13
    Description / Table of Contents: A review on past experimental and theoretical work indicates a need for additional experimentation to characterize the response of snow to inelastic pressure waves. Pressure data from previously conducted explosion tests are analyzed to estimate the elastic limit of snow of 400 -kg/cu m density to be about 36 kPa. This pressure corresponds to a scaled distance of 1.6 m/cu.rt.kg for charges fired beneath the surface of the snow, and to a scaled distance of 1.2 m/cu.rt.kg for charges fired in the air. The effects of a snow cover on the method of clearing a minefield by using an explosive charge fired in the air above the snow surface are also discussed and recommendations are given for further work in this area. Explosive pressure data are used to estimate the maximum effective scaled radius for detonating buried mines at shallow depth to be 0.8 m/cu.rt.kg. Fuel-air explosive will increase this effective radius significantly because of the increase in the size of the source region.
    Type of Medium: Series available for loan
    Pages: 33 Seiten , Illustrationen
    Series Statement: CRREL Report 83-13
    Language: English
    Note: CONTENTS Abstract Preface List of symbols Introduction Objectives Background Problems in describing the response of snow to an applied stress Methods of determining the dynamic behavior of materials Review of previous studies on snow Experimental measurements on snow Summary of snow experiments Theoretical studies Confirmation of the theory Discussion Applications Recommendations Summary Literature cited Appendix A. Selected data from Wisotski and Snyder (1966) Appendix B. Pressure data from Livingston (1964)
    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-201-83/11
    In: CRREL Report, 83-11
    Description / Table of Contents: Investigations of ground radar performance over thawed and seasonally frozen silts, and sands and gravels containing artificial and natural reflectors were carried out in Alaska. The radar emitted 5-10 ns pulses, the center frequency of which was approximately 150 MHz. The artificial reflectors were metal sheets and discs and the natural reflectors were the groundwater table and interfaces between frozen and thawed material. The water table was profiled at three sites where the subsurface material was coarse-grained alluvium. Dielectric constants of 16 to 18 were measured for the thawed silts, 6 to 7 for the frozen silts and 3 to 9 for the sands and gravels. Signal penetration in the thawed high moisture content silts may be achieved only by use of a lower frequency radar, whereas in the sands and gravels greater depths may be detected with more sophisticated signal processing.
    Type of Medium: Series available for loan
    Pages: 16 Seiten , Illustrationen
    Series Statement: CRREL Report 83-11
    Language: English
    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-201-83/25
    In: CRREL Report, 83-25
    Description / Table of Contents: Ice action on two cylindrical and conical structures, located side by side, was investigated in a small-scale experimental study to determine the interference on the ice forces generated during ice-structure interaction. The proximity of the two structures changes the mode of ice failure, the magnitude and direction of ice forces on the individual structure, and the dominant frequency of ice force variations. Interference effects were determined by comparing the experimental results of tests at different structure spacings.
    Type of Medium: Series available for loan
    Pages: 42 Seiten , Illustrationen
    Series Statement: CRREL Report 83-25
    Language: English
    Note: CONTENTS Abstract Preface Nomenclature Introduction Experimental setup and procedure Results and discussion Cylindrical structures Conical structures Conclusions Literature cited Appendix A: Relationship between flexural strength and in-situ unconfined compressive strength Appendix B: Test data
    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-201-84/19
    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 ...
  • 61
    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 ...
  • 62
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-82/12
    In: CRREL Report, 82-12
    Description / Table of Contents: From a high-quality set of velocity, temperature, and humidity profiles collected upwind and downwind of a step change in surface roughness, temperature, and moisture, we have calculated upwind and downwind values of the heat fluxes and friction velocity. The surface change is from smooth to rough; upwind, the sensible heat flux is upward and the latent heat flux is zero; downwind, the surface is well-watered so that the latent heat flux is upward while the sensible heat flux is downward. The downwind latent heat flux in this fetch-limited flow obeys NL=0.08 Rx 0.76 where NL is the latent heat Nusselt number and Rx is the fetch Reynolds number, a parameter for characterizing fetch-limited flows. Because this relation is virtually the same as one found to describe the sensible heat and condensate fluxes over arctic leads, we conclude that the Nusselt numbers nondimensionalizing scalar fluxes are the same for a given fetch Reynolds number when boundary conditions are similar.
    Type of Medium: Series available for loan
    Pages: vii, 18 Seiten , Illustrationen
    Series Statement: CRREL Report 82-12
    Language: English
    Note: CONTENTS Abstract Preface List of symbols Introduction Upwind: flux gradient method Downwind: integral method ResulIts Energy budget Latent heat flux Surface stress Downwind humidity profiles Discussion Conclusions Literature cited
    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
    Call number: ZSP-201-82/10
    In: CRREL Report, 82-10
    Description / Table of Contents: Dielectric measurements have been performed on silt and sand samples from permafrost areas using Time Domain Reflectometry. The sample temperatures were varied from +25 °C to -25 °C, and volumetric water content was varied between oven-dry and 0.55 gH2O/cm3. The data were processed for frequencies between 0.1 and 5.0 GHz. The results show a constant K' and a low K' for frequencies up to 1 GHz. A frequency dependence seen on the data above 2 GHz is probably the result of unfrozen, adsorbed water. At moisture levels near saturation at all temperatures, these soils have excellent propagation characteristics for ground-probing radar operating below 0.3 GHz. Massive ice should be easily detectable in permafrost within a few degrees of 0 °C.
    Type of Medium: Series available for loan
    Pages: 7 Seiten , Illustrationen
    Series Statement: CRREL Report 82-10
    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-201-82/13
    In: CRREL Report, 82-13
    Description / Table of Contents: Frost heave is analyzed for the common case in which some ice penetrates the soil. In this situation, heave is due to the accumulation of soil-free ice just within the frozen zone, behind a frozen fringe of finite thickness. Heat and mass transport within and across that fringe are crucial processes in the dynamics of heave. This analysis concentrates on activity within the fringe, also connecting that activity to heat and mass flows in the more frozen and unfrozen zones. Each component in a set of governing differential equations is developed from rational physics and thermodynamics, using previous experimental work. It is assumed that the soil ice grows through interconnected interstices; hence it constitutes and can move as a rigid body. When the assumption is translated into mathematical terms, it completes the governing equations. The model resulting from these considerations is a one-dimensional finite element computer program that solves the equations for arbitrary initial and boundary conditions. The model is used to simulate the heave history of a hypothetical soil column frozen unidirectionally and subjected to a surcharge. The results are gratifying in that they predict qualitatively the characteristics of numerous laboratory observations. Some questions about the completeness of the theory remain, and strict verification of the model awaits further experimentation and better parameter identification.
    Type of Medium: Series available for loan
    Pages: iii, 11 Seiten , Illustrationen
    Series Statement: CRREL Report 82-13
    Language: English
    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-201-80/9
    In: CRREL Report, 80-9
    Description / Table of Contents: Explosive cratering tests were conducted in seasonally frozen and thawed gravel at Ft. Richardson near Anchorage, Alaska, and in seasonallly frozen and thawed silt overlying permafrost and in silt permafrost at Ft. Wainwright near Fairbanks, Alaska. Explosive charge weights ranged from 26 to 3120 lb and charge burial depths ranged from about 3 to 40 ft. The cube root of the charge weight scaling was used to determine maximum scaled crater dimensions and optimum scaled depth of burial of the charge. Test results for frozen and thawed gravel were essentially the same because of the low moisture content and the relatively shallow depth of freezing (5 to 6 ft). The optimum depth of burial of the charge for maximizing the apparent radius and depth and the true radius was about 1.8 times the cube root of the charge weight for both the frozen and thawed conditions. In seasonally frozen silt overlying a talik and silt permafrost the maximum scaled crater dimensions and optimum scaled burial depths of the charge were smaller than for the thawed condition except for the true crater dimensions. The channeling of energy in the talik produces maximum crater dimensions and an optimum burial depth for the true crater that is larger than for the thawed condition. The results for the homogeneous silt permafrost were very similar to the frozen gravel results with much smaller maximum crater dimensions and smaller optimum charge burial depths than for the thawed silt overlying permafrost.
    Type of Medium: Series available for loan
    Pages: v, 21 Seiten , Illustrationen
    Series Statement: CRREL Report 80-9
    Language: English
    Note: CONTENTS Abstract Preface Metric conversion table Introduction Test sites Test procedures and materials Analysis of test data Mobility tests Conclusions Literature cited
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 66
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-80/8
    In: CRREL Report, 80-8
    Description / Table of Contents: This report presents the results of the tests on the new U.S. Coast Guard 140-ft icebreaker Katmai Bay (WTGB-101) in the level plate ice and brash ice in Whitefish Bay and the St. Marys River. The results indicate that the vessel can penetrate 22 in. of level freshwater ice with 2-3 in. of snow cover. It can also penetrate up to 48 in. of brash ice in a continuous mode and at least 30 in. of plate ice by backing and ramming. The installed bubbler system decreased the required power of the vessel from 10 to 30% in brash ice and 25 to 35% in level ice. The low friction coating appears to be effective in decreasing the friction factor when it remains intact; when it peels off it appears to make conditions worse than plain paint. An average dynamic friction factor of 0.15 could be used over the entire hull for these tests.
    Type of Medium: Series available for loan
    Pages: iv, 28 Seiten , Illustrationen
    Series Statement: CRREL Report 80-8
    Language: English
    Note: CONTENTS Abstract Preface Metric conversion table Introduction Roughness and friction measurements Level plate ice performance Brash ice performance Ramming icebreaking performance Analysis of the data Propulsion efficiency in ice Regression analysis Conclusions and recommendations Literature cited
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 67
    Call number: ZSP-201-80/10
    In: CRREL Report, 80-10
    Description / Table of Contents: A mathematical model of coupled heat and moisture flow in soils has been developed. The model includes algorithms for phase change of soil moisture and frost heave and permits several types of boundary and initial conditions. The finite element method of weighted residual (Galerkin procedure) was chosen to simulate the spatial regime and the Crank-Nicholson method was used for the time domain portion of the model. To facilitate evaluation of the model, the heat and moisture fluxes were essentially decoupled; moisture flux was then simulated accurately, as were heat flux and frost heave in a laboratory test. Comparison of the simulated and experimental data illustrates the importance of unsaturated hydraulic conductivity. It is one parameter which is difficult to measure and for which only a few laboratory test results are available. Therefore, unsaturated hydraulic conductivities calculated in the computer model may be a significant source of error in calculations of frost heave. The algorithm incorporating effects of surcharge and overburden was inconclusively evaluated. Time-dependent frost penetration and frost heave in laboratory specimens were closely simulated with the model. After 10 days of simulation, the computed frost heave was about 2.3 cm vs 2.0 cm and 2.8 cm in two tests. Frost penetration was computed as 15 cm and was measured at 12.0 cm and 12.2 cm in the two laboratory samples after 10 days.
    Type of Medium: Series available for loan
    Pages: v, 49 Seiten , Illustrationen
    Series Statement: CRREL Report 80-10
    Language: English
    Note: CONTENTS Abstract Preface Introduction One-dimensional equations of simultaneous heat and moisture flux Moisture transport Heat transport Phase change Coupling effects Frost heave algorithm Development of computer model Finite difference vs finite element method Finite element formulation Time domain solution Evaluation of the mathematical model Heat flux Moisture flux Numerical dispersion Frost heave of homogeneous laboratory samples Conclusions Recommended studies to refine the model Literature cited Appendix A. Work plan, staffing and instrumentation requirements for correlating results oflaboratory frost susceptibility tests with field performance Appendix B. Proposed investigation of thaw weakening of subgrade soil and granular unboundbase course Appendix C. Derivation of finite element system matrices
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 68
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-80/2
    In: CRREL Report, 80-2
    Description / Table of Contents: Winter thermal structure and ice conditions in the land-fast ice cover of Lake Champlain were studied in detail for the winters of 1975-76 and 1976-77. The lake was instrumented to a depth of 8.5 m with a string of highly calibrated thermistors attached to an ice mooring system and connected to a data logger at Shelburne Point, Vermont, during the winter of 1975-76 and at Gordon Landing on Grand Isle, Vermont, during 1976-77. This data logger automatically recorded water temperatures from the surface of the lake though snow, ice and water vertical profiles to the bottom of the lake every four hours. Pertinent meteorological parameters are presented for the appropriate measurement sites during the two winter periods, November '75-April '76, and November '76-April '77. Computations were made of freezing degree days (C) for both winters and correlated with ice formation dates. Predictions of ice growth, using the Stefan equation with an empirical coefficient, were correlated with actual ice growth. Documentation was made of the Lake Champlain Transportation Company's first attempt at wintertime navigation by ferry from Gordon Landing, Vermont, to Cumberland Head, New York, in a land fast ice cover during one of the coldest winters of this century.
    Type of Medium: Series available for loan
    Pages: iv, 26 Seiten , Illustrationen
    Series Statement: CRREL Report 80-2
    Language: English
    Note: CONTENTS Abstract Preface Introduction Objectives Climate Site preparation and data collection Instrumentation, measurements and calibration Relocation of measurement site, Fall 1976 Visual observations, ice conditions, and pertinent photography Analysis Air temperature comparisons Degree days of freezing Prediction of ice growth Water and ice temperature Wind Solar radiation Grand Isle ferry operations 1976-77 Conclusions Recommendations Literature cited Appendix A. General observations of ice conditions on Lake Champlain
    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-201-80/27
    In: CRREL Report, 80-27
    Description / Table of Contents: No general, analytical solution exists for phase change around a cylinder, thus, approximate methods have been evaluated. The heat balance integral technique applied to the cylinder gave excellent results when compared to published numerical solutions. Graphical solutions are given for phase change about a cylinder for ranges of the Stefan number, superheat parameter, and property value ratios for typical soils. An approximate, general solution has been derived which is reasonably accurate and can be used for any values of the above-mentioned parameters. The effective thermal diffusivity method has been shown to be useful for practical problems of phase change.
    Type of Medium: Series available for loan
    Pages: v, 18 Seiten , Illustrationen
    Series Statement: CRREL Report 80-27
    Language: English
    Note: CONTENTS Abstract Preface Nomenclature Introduction Zero superheat Constant phase change rate Zero sensible heat Finite sensible heat Finite superheat Quasi-steady solution Heat balance integral solution Approximate methods Conclusions Literature cited
    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-201-80/25
    In: CRREL Report, 80-25
    Description / Table of Contents: Two new types of load cells for attachment to bridge piers and direct measurement of ice forces were developed and tested with one type being installed on a pier of the Yukon River Bridge northwest of Fairbanks, Alaska. Both types of load cells used beams supported by base plates and carried nose plates that were loaded by the ice. The loads were imposed at the beams at locations differing from the support reactions so that the loads developed moments in the beams. By instrumenting them with strain gauges, the loads could be measured. Details of the design of the load cells, the means of calculating the loads and experience obtained with load cells are discussed.
    Type of Medium: Series available for loan
    Pages: iii, 17 Seiten , Illustrationen
    Series Statement: CRREL Report 80-25
    Language: English
    Note: CONTENTS Preface Conversion factors Introduction Estimates and field measurements of ice forces on structures General Indirect estimates Direct measurements Small-scale and laboratory studies Instrumentation plan for measuring ice loads on the Yukon River Bridge Load cell development The single reaction beam system Performance of a single reaction beam load cell The double reation beam load cell Reaction beam design Stress in the beam Deflection Axial tensile stress in the reaction beam Measurement techniques Conclusions Literature cited Appendix A. Finding load magnitude and location with a single reaction beam device Appendix B. Finding load magnitude and location on a double reaction beam device
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 71
    Call number: ZSP-201-80/20
    In: CRREL Report, 80-20
    Description / Table of Contents: Results of impulse radar studies of sea ice give support to the concept of a sea ice model in which the ice bottom is composed of an array of lossy parallel plate waveguides. The fundametal relation between the average bulk brine volume of sea ice and its electrical and strength properties is discussed as is the remote detection of under-ice current alignment. It was found that 1) the average effective bulk dielectric constant is dependent upon the average bulk brine volume of the sea ice; 2) sea ice anisotropy, arising from a bottom structure of crystal platelets with a preferred c-axis horizontal alignment, can be detected by radio echo sounding measurements made not only on the ice surface but also from an airborne platform; 3) the effective coefficient of reflection from the seaiIce bottom decreases with increasing average effective bulk dielectric constant of the ice, decreases with increasing bulk brine volume, and is typically one to two orders of magnitude lower dhan the coefficient of reflection from the ice surface; and 4) the losses In sea ice increase with increasing average bulk brine volume.
    Type of Medium: Series available for loan
    Pages: v, 18 Seiten , Illustrationen
    Series Statement: CRREL Report 80-24
    Language: English
    Note: CONTENTS Abstract Preface Introduction Field program Results and discussion Conclusions Literature cited Appendix: Data analysis procedures
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 72
    Call number: ZSP-201-80/4
    In: CRREL Report, 80-4
    Description / Table of Contents: The primary objectives of this study were to 1) prepare a map from Landsat imagery of the Upper Susitna River Basin drainage network, lakes, glaciers and snowfields, 2) identify possible faults and lineaments within the upper basin and within a 100-km radius of the proposed Devil Canyon and Watana dam sites as observed on Landsat imagery, and 3) prepare a Landsat-derived map showing the distribution of surficial geologic materials and poorly drained areas. The EROS Digital Image Enhancement System (EDIES) provided computer- enhanced images of Landsat-1 scene 5470-19560. The EDIES false color composite of this scene was used as the base for mapping drainage network, lakes, glaciers and snowfields, six surficial geologic materials units and poorly drained areas. We used some single-band and other color composites of Landsat images during interpretation. All the above maps were prepared by photointerpretation of Landsat images without using computer analysis, aerial photographs, field data, or published reports. These other data sources were used only after the mapping was completed to compare and verify the information interpreted and delineations mapped from the Landsat images. Four Landsat-1 MSS band 7 winter scenes were used in the photomosaic prepared for the lineament mapping. We mapped only those lineaments related to reported regional tectonics, although there were many more lineaments evident on the Landsat photomosaic.
    Type of Medium: Series available for loan
    Pages: iii, 41 Seiten , Illustrationen
    Series Statement: CRREL Report 80-4
    Language: English
    Note: CONTENTS Abstract Preface Summary Objectives Conclusions Introduction Background Previous cooperative investigations Project rationale and coordination Approach Landsat imagery Interpretation techniques Part I. Use of Landsat imagery in mapping the drainage network, lakes, glaciers and snowfields (Lawrence W. Gatto) Objective Methods Results Conclusions Part II. Use of Landsat imagery in mapping and evaluating geologiclineaments and possible faults (Carolyn J. Merry) Objective Geologic structure Methods Results Conclusions Part Ill. Use of Landsat imagery in mapping surficial materials Section A. Landsat mapping (Harlan L. McKim) Objective Methods Results Section B. Field evaluation (Daniel E. Lawson) Objectives Methods Results Discussion Section C. Conclusions (Daniel E. Lawson and Harlan L. McKim) Literature cited Glossary
    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-201-80/3
    In: (DE-B103)105551, CRREL Report
    Description / Table of Contents: Revegetation techniques were investigated for gravel soils in cold regions. Two gravel soil test sites were established in Hanover, New Hampshire, and Fairbanks, Alaska. During three growing seasons, we studied the applicability and cost effectiveness of various nutrient sources and mulch materials. The nutrient sources included sewage sludge (at 40, 60 and 80 tons/acre) and commercial fertilizer (at 200, 400 and 600 lb/acre). The mulching materials were wood fiber mulch with various types of tackifiers, peat moss, and sewage sludge. The effects of refertilization during the second growing season were also studied. At both sites the use of sewage sludge produced superior results in many respects to the use of fertilizer at the application rates studied. Grasses receiving sludge showed better establishment rates and greater plant cover and growth, and were able to withstand the hot drying conditions encountered during the summer months. Slightly quicker grass establishment was noted at the higher rates of application of each nutrient source in Fairbanks, while grass establishment at all sludge rates was good in Hanover. All fertilizer treatments performed poorly in Hanover. No evidence of winter injury to the grasses was noted in any of the treatments. Supplemental applications of nitrogen fertilizer in Hanover during spring of the second growing season proved highly beneficial. The fertilizer helped maintain grass growth even during dry summer conditions. The mulches were applied at the rate of 2,000 lb/acre. They were found to be important in providing a more nearly optimum environment for seedling establishment. Wood fiber mulch and the commercial Wood Fiber Mulch 2000, generally, were the best performers.
    Type of Medium: Series available for loan
    Pages: vi, 21 Seiten , Illustrationen
    Series Statement: CRREL Report 80-3
    Language: English
    Note: CONTENTS Abstract Preface Introduction Literature review Experimental design Climate Results and discussion Nutrient sources Mulches Soil fertility Cost analysis Summary and conclusions 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-201-80/31
    In: CRREL Report, 80-31
    Description / Table of Contents: Ice accretion on structures built on the earth’s surface is discussed. Sources of water are the atmosphere or water bodies near or surrounding the structure. Ice types include frost, rime, glaze, and spray; properties and conditions governing their formation are presented. Methods of estimating accretion rates and total accretion on structures are given, and extracts from U.S. and Canadian codes for ice and wind loads on structures are included. Techniques for preventing or removing ice accretion are presented.
    Type of Medium: Series available for loan
    Pages: iv, 18 Seiten , Illustrationen
    Series Statement: CRREL Report 80-31
    Language: English
    Note: CONTENTS Abstract Preface 1. Types of ice accretion a. Frost b. Rime c. Glaze d. Spray ice 2. Conditions governing type of accreted ice a. Meteorological b. Structural 3. Accretion rates a. Fundamentals b. Effect of height c. Geographical distribution 4. Spray icing 5. Structural design factors a. Dead loads b. Wind field in the boundary layer c. Windloads 6. Techniques for minimizing structural icing 7. Data collection needs 8. 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-201-82/6
    In: CRREL Report, 82-6
    Description / Table of Contents: The interpretation of continuous radar profiles requires an alternative geophysical means of obtaining ground dielectric information. Ground dielectric properties were measured using wide-angle reflection and refraction (WARR) soundings with a ground-probing radar set that transmits pulses f a few nanoseconds duration. The investigations, carried out over sandy gravel in interior Alaska, provided dielectric data to about a 5-m depth. The WARR soundings were displayed as individual traces allowing interference between separate events and dispersion to be observed, and the soundings were compared with continuous radar and resistivity profiles conducted concurrently to extract the maximum amount of dielectric information. The dielectric constants, derived mainly from the direct ground waves propagating along the surface, ranged from 2.9 to 7.4. Dielectric values interpreted for one site predicted the possibility of a refracted event which may have occurred during one of the soundings.
    Type of Medium: Series available for loan
    Pages: iii, 11 Seiten , Illustrationen
    Series Statement: CRREL Report 82-6
    Language: English
    Note: CONTENTS Abstract Preface Introduction Theory of ground wave propagation from a horizontal electric dipole Equipment and methods Results Site 1 Site 2 Site 3 Summary and concluding remarks Literature cited
    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-201-81/24
    In: CRREL Report, 81-24
    Description / Table of Contents: This report develops a method of analysis for heat transmission systems operating under district heating load conditions. The method accounts for the effects of heat source and load characteristics. The use of thermal energy storage systems is outlined and advantages are given. The transmission model itself considers the following technical aspects: (1) frictional pressure losses in piping system, (2) pump characteristics, (3) pump driver characteristics, and (4) heat losses from the buried piping. The capital costs considered are the piping system and necessary pumps. Operation and maintenance costs include cost of heat loss and cost of pumping energy input. Allowances are also made for system maintenance and repair over the assumed lifetime.
    Type of Medium: Series available for loan
    Pages: vii, 53 Seiten , Illustrationen
    Series Statement: CRREL Report 81-24
    Language: English
    Note: CONTENTS Abstract Preface Nomenclature Introduction Modes of heat transmission History and state of the art Technical aspects of heat transmission systems Heat sources Space heating loads Thermal energy storage Fluid dynamics considerations Pump drivers Buried piping systems Economic aspects of heat transmission systems Capital costs Operation and maintenance costs Problem formulation Criteria for the optimum solution The objective function Problem solution The response surface Methods of solution Sample results, conclusions and suggestions for future work Results from model calculations Conclusions and suggestions for future work Literature cited Appendix A: Computer program listing
    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-201-81/25
    In: CRREL Report, 81-25
    Description / Table of Contents: The problem of heat conduction with phase changeAoften called the Stefan problemrincludes some of the mostintractable mathematical areas of heat transfer. Exact solutions are extremely limited and approximate methodsare widely used. This report discusses the collocation method for the heat balj ce integral approximation. The methodis applied to some standard problems of phase change-Neumann's problem-and a new solution is presented for thecase of surface convection for a semi-infinite body. Numerical results are given for soil systems and also for materialsof interest in latent heat thermal storage.
    Type of Medium: Series available for loan
    Pages: v, 14 Seiten , Illustrationen
    Series Statement: CRREL Report 81-25
    Language: English
    Note: CONTENTS Abstract Preface Nomenclature Conversion factors Introduction Collocation method Neumann problem Specified surface heat flux Convective surface heat flux Insulated semi-infinite body Conclusion Literature cited Appendix A: Program listing for numerical quadrature of equation 28
    Location: AWI Archive
    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-201-81/26
    In: CRREL Report, 81-26
    In: Mechanics of cutting and boring, Part 7
    Description / Table of Contents: Abstract: This report deals with force, torque, energy and power in machines such as drills and boring devices, where the cutting head rotates about a central axis while penetrating parallel to that axis. Starting from a cosideration of the forces developed on individual cutting tools, or segments of cutters, the thrust and torque on a complete cutting head is assessed, and simple relationships between thrust and torque are derived. Similarly, the energy and power needed to drive the cutting head arc estimated and related to tool characteristics. Design characteristics of existing machines are compiled and analyzed to give indications of thrust, torque, power, effective tool forces, nominal thrust pressure, power density, and specific energy.
    Type of Medium: Series available for loan
    Pages: iv, 38 Seiten , Illustrationen
    Series Statement: CRREL Report 81-26
    Language: English
    Note: CONTENTS Abstract Preface Foreword Introduction Terminology Tool forces Parallel motion tools Indentation tools Head thrust, thrust per unit width, and nominal head pressure Power and power density Torque Specific energy Efficiency and performance index Power requirements for clearance of cuttings Minimum power requirements for lifting cuttings in a vertical hole Power consumption and efficiency in continuous-flight augers Air circulation Mud circulation Literature cited Appendix A: Vertical conveyance by continuous-fiight augers Appendix B: Surface areas on a helical flight and its stem
    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-201-82/3
    In: CRREL Report, 82-3
    Description / Table of Contents: The conditions that lead to initial breakup of a solid ice on a river due to rapid water level variations are analyzed. The analysis is based on the theory of beams on an elastic foundation. First cracking is assumed to occur when the bending moment induced in the ice cover by the wave exceeds the flexural strength of the ice cover.
    Type of Medium: Series available for loan
    Pages: iv, 17 Seiten , Illustrationen
    Series Statement: CRREL Report 82-3
    Language: English
    Note: CONTENTS Abstract Preface Symbols Introduction Purpose of the study Stating the problem Fracturing of the ice cover due to the passage of surge waves Basic assumptions Derivation of the bending moments Determination of the wave characteristics Deflection of the ice Discussion and field observations Summary Literature cited
    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-201-82/1
    In: CRREL Report, 82-1
    Description / Table of Contents: On 27 March 1964 a major earthquake struck Southern Alaska. The city of Anchorage, which contained a large part of Alaska's population, suffered loss of life and destruction of property. The time of the day, the season, and ground conditions were such that loss of life and property was minimized. The frozen ground and the ice on fresh waster bodies responded to the earthquake shocks in a seldom-observable pattern, which was noted and recorded. Changes of sea level and slides into the sea were responsible for waterfront destruction. It is concluded that the main factor that limited structural damage was the frozen state of the ground.
    Type of Medium: Series available for loan
    Pages: iv, 26 Seiten , Illustrationen
    Series Statement: CRREL Report 82-1
    Language: English
    Note: CONTENTS Abstract Preface Abstract of events Earthquakes and frozen ground The response of freshwater ice sheets to earthquake shock The earthquake disturbance in glaciated mountains Disturbed wildlife Tidal waves Summary Literature cited
    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-201-81/27
    In: CRREL Report, 81-27
    Description / Table of Contents: Existing classifications for deposits in the glacial environment are inadequate and inconsistent. Deposits should be classified both descriptively and genetically; adequate descriptive classifications already exist. A major problem for previous genetic classifications has been that glacial deposition and the resulting deposits' properties were poorly understood. On the basis of three criteria-sediment source, uniqueness to the glacial environment, and preservation of glacier-derived properties-deposits in the glacial environment result from either of two groups of processes: primary or secondary. Primary processes release the debris of the glacier directly and form deposits that may bear properties related to the glacier and its mechanics. Their deposits are classified genetically as till and are the only deposits indicative of glaciation. In contrast, secondary processes mobilize, rework, transport and resediment debris and deposits in the glacial environment. They develop new, nonglacial properties in their deposits, while destroying or substantially modifying glacier-derived properties. Interpretation of their properties may provide information on the depositional are classified genetically according to the depositional process just as they are in other sedimentary environments. This genetic classification differs from previous classifications in that not all diamictons deposited in the glacial environment are classified as till; it is based strictly on process-related criteria. The origin of properties of glacial deposits in relation to the glacier's mechanics and environment must be recognized if the mechanisms and depositional processes of former glaciers are to be precisely understood.
    Type of Medium: Series available for loan
    Pages: iii, 16 Seiten , Illustrationen
    Series Statement: CRREL Report 81-27
    Language: English
    Note: CONTENTS Abstract Preface Introduction Criteria for process grouping Depositional processes Deposit groups-tills and nontills Comparison of melt-out and sediment flow Melt-out Sediment flow Classification of glacial deposits Conclusions Literature cited
    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-201-82/41
    In: CRREL Report, 82-41
    Description / Table of Contents: Many of the important factors influencing the choice of appropriate aquifer test procedures are presented. The concepts of bias, accuracy and spatial variabil­ity are explained. The definitions of a number of aquifer parameters are devel­oped from basic principles demonstrating the underlying assumptions and limita­tions. The parameters considered are: piezometric head, hydraulic conductiv­ity/intrinsic permeability, flow direction, specific discharge magnitude, transmissivity, volumetric flow rate, total porosity, effective porosity, aver­age linear velocity, storage coefficient, specific yield, dispersion coefficient-aquifer dispersivity. For each parameter several techniques are described, evaluated and ranked in terms of perceived potential accuracy, simplicity and value to contaminant transport studies. It must be stressed, however, that the evaluations are based principally upon theoretical grounds, and not upon actual conduct of the described procedures.
    Type of Medium: Series available for loan
    Pages: iv, 111 Seiten , Illustrationen
    Series Statement: CRREL Report 82-41
    Language: English
    Note: CONTENTS Abstrac Preface Introduction Purpose Scope Concept of accuracy Test selection Definition of parameters Piezometric head Use of piezometers Hydraulic conductivity Flow direction Specific discharge magnitude Transmissivity Volumetric flow rate Porosity Average linear velocity Storage coefficient-specific yield Aquifer dispersivity Parameter estimation techniques Piezometric head Hydraulic conductivity Direction and magnitude of specific discharge vector Transmissivity Volumetric flow rate Total porosity Average linear velocity Storage coefficient Specific yield Effective porosity Aquifer dispersivity-dispersion coefficients Conclusions Literature cited
    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-201-83/4
    In: CRREL Report, 83-4
    Description / Table of Contents: Measurements and analysis of seasonal ice growth and decay on Post Pond, New Hampshire, for the period 1973-1982 are presented. Observations included ice thickness measurements, examination of the various ice types contributing to the ice cover, and measurements of meteorological parameters for correlation with and modeling of the ice growth process. The overall nature of ice growth and decay (ice loss) on the Post Pond has been ascertained, the seasonal variability in the timing of freeze-up and ice-out and the duration of the ice cover have been determined, and the relationship of ice growth to freezing-degree-day (deg C) records evaluated on the basis of a Stefan conduction equation modified to deal with ice sheets covered with or free of snow. Ice growth occurs predominantly by the direct freezing of lake water, but snow ice may compose as much as 50% of the ice cover in winters with higher than average snowfall. Freeze-up leading to the establishment of a stable ice cover occurs during the 4-week period from the end of November to the end of December. Maximum seasonal ice thicknesses were from 45 to 67 cm and are generally attained during the first two weeks of March; ice-out, marking the final disappearance of ice from Post Pond, usually occurs by the third week of April. The overall rate of the ice loss is three to four times that of ice growth, and is dominated initially by melting from the top. As much as 50% of the ice may be lost in this way before the onset of any bottom melting. Final dissipation of the ice cover is usually expedited by candling resulting from preferential melting and disintegration of the ice at crystal boundaries.
    Type of Medium: Series available for loan
    Pages: iv, 30 Seiten , Illustrationen
    Series Statement: CRREL Report 83-4
    Language: English
    Note: CONTENTS Abstract Preface Introduction Location of study Study methods Ice thickness Ice-cover composition Surface air temperatures Freeze-up and ice-out characteristics Results and discussion Ice-growth record Freezing-degree-day records Ice-growth predictions Summary and conclusions Literature cited Appendix A: Ice-growth records Appendix B: Measured and computed ice-growth curves
    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-201-82/38
    In: CRREL Report, 82-38
    Description / Table of Contents: Extreme cold causes heavy buildup of frost, ice and condensation on many windows. It also increases the incentive for improving the airtightness of windows against heat loss. Our study shows that tightening specifications for Alaskan windows to permit only 30% of the air leakage allowed by current American airtightness standards is economically attractive. We also recommend triple glazing in much of Alaska to avoid window icing in homes and barracks. We base our conclusions on a two-year field study of Alaskan military bases that included recording humidity and temperature data, observing moisture accumulation on windows and measuring airtightness with a fan pressurization device.
    Type of Medium: Series available for loan
    Pages: v, 26 Seiten , Illustrationen
    Series Statement: CRREL Report 82-38
    Language: English
    Note: Contents Abstract Preface Nomenclature Introduction Previous work in cold weather window performance Investigation Data acquisition and analysis Modeling the window thermal regime Moisture and ice observations Airtightness testing and analysis Annual heat loss from air leakage Results and conclusions Moisture on windows Airtightness Airtightness economics Recommendations for windows in extreme cold Airtightness Multiple glazing Literature cited Appendix A: Moisture levels and airtightness Appendix B: Dewpoint data Appendix C: Sample observations of icing
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 85
    Call number: ZSP-201-83/21
    In: CRREL Report, 83-21
    Description / Table of Contents: The probability density function of the gouge depths into the sediment is represented by a simple negative exponential over four decades of gouge frequency. The exceedance probability function is, therefore, e to the -lambda d, where d is the gouge depth in meters and lambda is a constant. The value of lambda shows a general decrease with increasing water depth, from 9/m in shallow water to less than 3/m in water 30 to 35 m deep. The deepest gouge observed was 3.6 m, from a sample of 20,354 gouges that have depths greater than or equal to 0.2 m. The dominant gouge orientations are usually unimodal and reasonably clustered, with the most frequent alignments roughly parallel to the general trend to the coastline. The value of N(bar) sub 1, the mean number of gouges (deeper than 0.2 m) per kilometer measured normal to the trend of the gouges, varies from 0.2 for protected lagoons to 80 in water between 20 and 38 m deep in unprotected offshore regions. The distribution of the spacings between gouges as measured along a sampling track is a negative exponential. The form of the frequency distribution of N sub 1 varies with water depth and is exponential for lagoons and shallow offshore areas, previously skewed for 10 to 20 m depths off the barrier islands, and near-normal for deeper water. As a Poisson distribution gives a reasonable fit to the N sub 1 distributions for all water depths, it is suggested that gouging can be taken as approximating a Poisson process in both space and time. The distributions of the largest values per kilometer of gouge depths, gouge widths, and the heights of the lateral embankment of sediments plowed from the gouges are also investigated.
    Type of Medium: Series available for loan
    Pages: 40 Seiten , Illustrationen, 1 Karte
    Series Statement: CRREL Report 83-21
    Language: English
    Note: CONTENTS Abstract Preface Introduction Background and environmental setting Data collection and terminology Data analysis Gouge depths Gouge orientation Gouge frequency Extreme value analysis Applications to offshore design Gouge depth Extreme value statistics Burial depths Conclusion Literature cited Appendix A: Detailed bathymetric map of the Alaskan portion of the Beaufort Sea
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 86
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-83/16
    In: CRREL Report, 83-16
    Description / Table of Contents: The presence of snow on the ground can impose limitations on the mobility of wheeled and tracked vehicles. Snow depth and density are the two most easily measured snow properties that can be related to mobility over snow. Existing models of snowpack accumulation and ablation processes and models of internal snowpack structure were examined to determine if a model of the snowpack can be developed for use in predicting the snow parameters that affect mobility. Simple models, such as temperature index models, do not provide sufficient snowpack details, and the more detailed models require too many measured inputs. Components of the various models were selected from a basis of a snowpack model for predicting snow properties related to mobility over snow. Methods of obtaining the input data from some components are suggested, and areas where more development is needed are described.
    Type of Medium: Series available for loan
    Pages: 34 Seiten , Illustrationen
    Series Statement: CRREL Report 83-16
    Language: English
    Note: CONTENTS Abstract Preface Nomenclature Conversion of metric units Introduction Review of existing models Accumulation models Ablation models Using existing models for studying mobility Proposed snowpack model for mobility studies Model components Implementation of the model Developing input data Conclusions Literature cited
    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-201-83/23
    In: CRREL Report, 83-23
    Description / Table of Contents: The problems associated with measuring stresses in ice are reviewed. Theory and laboratory test results are then presented for a stiff cylindrical sensor made of steel that is designed to measure ice stresses in a biaxial stress field. Loading tests on freshwater and saline ice blocks containing the biaxial ice stress sensor indicate that the sensor has a resolution of 20 kPa and an accuracy of better than 15% under a variety of uniaxial and biaxial loading conditions. Principal stress directions can also be determined within 5 degrees. The biaxial ice stress sensor is not significantly affected by variations in the ice elastic modulus, ice creep or differential thermal expansion between the ice and gauge. The sensor also has a low temperature sensitivity (5 kPa/deg C).
    Type of Medium: Series available for loan
    Pages: 38 Seiten , Illustrationen
    Series Statement: CRREL Report 83-23
    Language: English
    Note: CONTENTS Abstract Preface Introduction Previous work Stress measurements Design considerations Stress sensors Biaxial ice stress sensor Biaxial stress sensor theory Gauge deformation Stresses associated with cylindrical sensors Determination of ice stresses Gauge calibration Evaluation of the biaxial ice stress sensor Temperature sensitivity Biaxial loading test equipment Biaxial loading test results Differential thermal expansion Long-term drift Discussion of test results Conclusions Literature cited
    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-201-83/30
    In: CRREL Report, 83-30
    Description / Table of Contents: Ice sheets are formed and retained in several ways in nature, and an understanding of these factors is needed before most structures can be successfully applied. Many ice sheet retention structures float and are somewhat flexible; others are fixed and rigid or semirigid. An example of the former is the Lake Erie ice boom and of the latter, the Montreal ice control structure. Ice sheet retention technology is changing. The use of timber cribs is gradually but not totally giving way to sheet steel pilings and concrete cells. New structures and applications are being tried but with caution. Ice-hydraulic analyses are helpful in predicting the effects of structures and channel modifications on ice cover formation and retention. Often, varying the flow rate in a particular system at the proper time will make the difference between whether a structure will or will not retain ice. The structure, however, invariably adds reliability to the sheet ice retention process.
    Type of Medium: Series available for loan
    Pages: iv, 39 Seiten , Illustrationen , 1 Beilage
    Series Statement: CRREL Report 83-30
    Language: English
    Note: Contents Abstract Preface Introduction Natural ice sheets Choosing an ice control structure Flexible structures Ice booms Frazil collector lines Fence booms Rigid or semirigid structures Pier-mounted booms Stone groins Artificial islands Removable gravity structures Timber cribs Weirs Pilings and dolphins Structures built for other purposes Hydroelectric dams Wicket dams Light piers and towers Bridge piers Breakwaters Ice control not using Structures Channel improvements Ice sheet tying Ice sheet bridges Conclusions Literature cited Appendix A: Ice control structure
    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-201-83/31
    In: CRREL Report, 83-31
    Description / Table of Contents: A mathematical model is described that is used to determine the maximum ice conveyance capacity of a river channel. Based upon this model, computer programs were developed that enable the ice discharge to be calculated for steady-state flow conditions. For rivers that have uniform flow, the maximum ice-conveying capacity can be described with a simple function expressed in terms of the size of the ice fragments, channel geometry, and the flow of water in the river. For nonuniform flows, the computer program determines the elevation profile of the surface layer in addition to other flow characteristics, such as the velocity and surface concentration of the ice fragments. The location along this surface profile where the ice conveyance capacity becomes less than the upstream supply is determined and is considered to be the position where a surface ice jam or ice bridge will be formed.
    Type of Medium: Series available for loan
    Pages: iv, 21 Seiten , Illustrationen
    Series Statement: CRREL Report 83-31
    Language: English
    Note: CONTENTS Abstract Preface Nomenclature Introduction Constitutive relationships Equations of motion Uniform flow Nonuniform flow Ice transport: Uniform flow Symmetric channel Asymmetric channel Ice transport: Nonuniform flow Further considerations Basis for model improvement Conclusions Literature cited
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 90
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-83/29
    In: CRREL Report, 83-29
    Description / Table of Contents: A literature review indicated that the effects or permafrost on streambank erodibility and stability are not yet understood because systematic and quantitative measurements are seriously lacking. Consequently, general controversy exists as to whether perennially frozen ground inhibits lateral erosion and bankline recession, or whether it increases bank recession rates. Perennially frozen streambanks erode because of modification of the bank's thermal regime by exposure to air and water, and because of various erosional processes. Factors that determine rates and locations of erosion include physical, thermal and structural properties of bank sediments, stream hydraulics and climate. Thermal and physical modification of streambanks may also induce accelerated erosion within permafrost terrain removed from the immediate river environment. Bankline or bluffline recession rates are highly variable, ranging from less than 1 m/year to over 30 m/year and, exceptionally, to over 60 m/year. Long-term observations of the physical and thermal erosion processes and systematic ground surveys and measurements of bankline-bluffline recession rates are needed.
    Type of Medium: Series available for loan
    Pages: iv, 26 Seiten , Illustrationen
    Series Statement: CRREL Report 83-29
    Language: English
    Note: CONTENTS Abstract Preface Introduction Stream bank erosional processes Permafrost and related factors Permafrost and erosion General Erosional processes Bank zone processes Bluff zone processes Factors affecting perm afrost erodibility Exposure to currents and wind waves Texture and stratigraphy Ice content, distribution and type Slope aspect Coriolis force Timing and depth of thaw Water level and temperature Vegetation Ice and snow cover Groundwater Rates and timing of erosion and recession Overall effects of permafrost Recommendations for research Literature cited Appendix A : Processes of stream bank modifications
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 91
    Call number: ZSP-201-83/32
    In: CRREL Report, 83-32
    Description / Table of Contents: Ice forces on a bridge pier in the Ottauquechee River, in Quechee, Vermont, were measured by installing fourpanels-each capable of measuring forces in the normal and tangential direction - on both sides of a vertical V-shaped pier nose. The measured forces are presented for a short period during an ice run. After the ice run, the thickness and sizes of the ice floes were measured and the compressive strength of the ice was determined in the laboratory from the ice samples collected along the river banks. The water level measurements made at several locations along theriver are also presented for the period of the ice run.
    Type of Medium: Series available for loan
    Pages: ii, 8 Seiten , Illustrationen
    Series Statement: CRREL Report 83-32
    Language: English
    Location: AWI Archive
    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-201-83/33
    In: CRREL Report, 83-33
    Description / Table of Contents: A thermodynamic model has been developed that for the first time describes the entire creep process, including primary, secondary, and tertiary creep, and failure for both constant stress (CSR) tests (σ= const.) and constant strain rate (CSR) tests (ϵ = const.), in the form of a unified constitutive equation and unified failure criteria. Deformation and failure areconsidered as a single thermoactivated process in which the dominant role belongs to the change of entropy. Failure occurs when the entropy change is zero. At that moment the strain rates in CS tests reach the minima and stress in CSR tests reaches the maximum (peak) values. Families of creep (ϵ vs τ) and stress-strain (σ vs ϵ) curves, obtained from uni-axial compression CS and CSR tests of frozen soil, respectively (both presented in dimensionless coordinates), are plotted as straight lines and are superposed, confirming the unity of the deformation and failure process and the validity of the model. A method is developed for determining the parameters of the model, so that creep deformation and the stress-strain relationship of ductile materials such as soils can be predicted based upon information obtained from either type of test.
    Type of Medium: Series available for loan
    Pages: v, 25 Seiten , Illustrationen
    Series Statement: CRREL Report 83-33
    Language: English
    Note: CONTENTS Abstract Nomenclature Introduction Principal relationships Constitutive equation Failure criteria Secondary creep: Flow equations Creep at constant stress (σ = Const.) Creep model Creep strain (σ = Const.) Creep at constant strain rate (ϵ = Const.) Stress-strain relationship Stress/strain/strain rate at failure Test data Preliminary analysis Constant stress tests (σ = Const.) Constant strain rate tests (ϵ = Const.) The principle of superposition Thermodynamic equation of creep Conclusions Literature cited
    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-201-84/2
    In: CRREL Report, 84-2
    Description / Table of Contents: Investigations of the in situ complex dielectric constant of sea ice were made using time-domain spectroscopy. It was found that (1) for sea ice with a preferred horizontal crystal c-axis alignment, the anisotropy of polarizing properties of the ice increased with depth, (2) brine inclusion conductivity increased with decreasing temperature down to about -8 C, at which point the conductivity decreased with decreasing temperature, (3) the DC conductivity of sea ice increased with increasing brine volume, (4) the real part of the complex dielectric constant is strongly dependent upon brine volume but less dependent upon the brine inclusion orientation, (5) the imaginary part of the complex dielectric constant was strongly dependent upon brine inclusion orientation but much less dependent upon brine volume. Because the electromagnetic (EM) properties of sea ice are dependent upon the physical state of the ice, which is continually changing, it appears that only trends in the relationships between the EM properties of natural sea ice and its brine volume and brine inclusion microstructure can be established.
    Type of Medium: Series available for loan
    Pages: vi, 38 Seiten , Illustrationen , 1 Beilage
    Series Statement: CRREL Report 84-2
    Language: English
    Note: CONTENTS Abstract Preface Nomenclature Introduction Dielectric properties of sea ice Time-domain spectroscopy measurement Laboratory measurements Field measurements Analysis of ladder data Conductivity of brine and sea ice Complex dielectric constant of brine and sea ice Discussion and conclusions Literature cited
    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-201-84/7
    In: CRREL Report, 84-7
    Description / Table of Contents: Experiments were conducted in CRREL's refrigerated flume facility to examine the two-dimensional force distribution of a floating, fragmented ice cover restrained by a boom in a simulated river channel. To determine the force distribution, a vertically walled channel, instrumented for measuring normal and tangential forces, and an instrumented restraining boom were installed in a 40.0- by 1.3-m flume. Two sizes of polyethylene blocks and two similar sizes of fresh-water ice blocks were tested using water velocities ranging from 10 to 30 cm/s. The forces measured at the instrumented boom leveled off with increasing cover length. The contribution of the increasing shear forces developed along theshorelines to this leveling off in the data was clearly evident. The shear coefficients of the polyethylene blocks averaged 0.43, and the freshwater ice averaged 0.044. The normal force measured along the instrumented shoreline could not be related simply by a K coefficient to the longitudinal force; another expression was required, with a term being a function of the cover thickness and independent of the undercover shear stress or cover length. By adding this term, good agreement was then found between the measured and predicted values of the boom forces and the shoreline normal and shear forces
    Type of Medium: Series available for loan
    Pages: iv, 22 Seiten , Illustrationen
    Series Statement: CRREL Report 84-7
    Language: English
    Note: CONTENTS Abstract Preface Introduction Experiments Test flume facility Experimental apparatus Experimental procedure Results Plastic versus freshwater ice Shoreline forces Boom forces Average shear stress under ice cover Internal forces Discussion Data scatter Summary and conclusions Literature cited Appendix A: Experimental results
    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-201-84/8
    In: CRREL Report, 84-8
    Description / Table of Contents: This report describes the equipment and procedures that were used for acquiring, preparing and testing samples of multi-year sea ice. Techniques and procedures are discussed for testing ice samples in compression and tension at constant strain rates and constant loads, as well as in a conventional triaxial cell. A detailed account is given of the application and measurement of forces and dispiacements on the ice test specimens under these different loading conditions.
    Type of Medium: Series available for loan
    Pages: iv, 43 Seiten , Illustrationen
    Series Statement: CRREL Report 84-8
    Language: English
    Note: CONTENTS Abstract Preface Introduction Test material and test specimens Test material Required dimensions for test specimens Acquisition and preparation of specimens Field core sampling Specimen preparation in the laboratory Application of forces and displacements to uniaxial specimens Compression Tension Squareness imperfections Loading devices Universal testing machine Gas actuator for constant load Weight-and-pulley system for constant tension Equipment for triaxial tests Measurement of force and displacement Force Displacement Readouts and recorders Literature cited Appendix A: Phenolic-resin end caps Appendix B: Compliant platens Appendix C: Theoretical factor for converting overall strain to gauge-length strain indumbbell specimens Appci dix D: Items developed but not used in Phase I Appendix E: Use of the Brazil test
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 96
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-84/32
    In: CRREL Report, 84-32
    Description / Table of Contents: Orwell Lake, in west-central Minnesota, is a flood-control, water-management reservoir first impounded in 1953. Subsequent erosion of the shoreline and a lack of knowledge of slope erosion processes in this region prompted this study to identify and quantify the processes there. The processes were measured at selected sites between June 1980 and June 1983. Erosion of the banks is primarily caused by three processes: rain, frost thaw, and waves. The first two processes tend to move sediment to the base of the steep slopes, forming 4 relatively gentle surface of accumulation. Wave action then tends to move this sediment into the lake. Analysis of the data collected over three years has confirmed that wave action is the dominant erosion process, providing almost 77% of the erosion during the 1981-82 study year. During the 1981 high pool level, 2,089 Mg of sediment, mostly colluvium, was removed from the lower slopes by wave action striking the 1.62 km of eroding shoreline. More than 4,300 Mg was eroded by waves accompanying the higher pool levels of 1982., During years in which the pool level does not exceed 325.5 m in elevation, the colluvium slope builds up at the expense of the steeper slope. But during successive years with higher pool levels, the resulting thin colluvium is quickly eroded. Erosion of the primary sediment, a compact till, then occurs, forming the S typical nearly vertical banks. In winter the upland surface adjacent to the lake freezes to a depth of between 1 and 2 m, depending on the surface temperature, the mow cover, and the distance from exposed banks. In late winter soil aggregates, released by the sublimation of interstitial ice within the banks, begin to accumulate at the base of the slopes, often veneering snowbanks there. Once thaw begins, slab failure of bank sediment is followed by mudflows and earthflows. Thaw failure at Orwell Lake in the winter of 1981-82 accounted for over 20% of the erosion; in the spring of 1982, 824 Mg was eroded by this process and 746 Mg the following spring. Such slope failure is most intense along north-facing banks and considerably less intense on south-facing banks, where more effective desiccation and sublimation reduce the soil moisture content. Summer rainfall is responsible for the remaining 3% of the total erosion, amounting to 102 Mg in 1981 and 208 Mg in 1982. Because the banks are steep and relatively short, rainwash is infrequent; rainsplash is the most consistent process during the summer, but the infrequent storms during which rainwash occurscause greater total erosion. Erosion by rain has increased in each of the past three summers, largely because of increased precipitation. Infrequent massive slope failures (slumps) have occurred at the east end of the lake where a buried clay rich unit is stratigraphically and topographically positioned to favor such failures. Drought years followed by heavy spring rains probably will result in additional slope failures of this type at the east end. Unless changes are made, the banks at Orwell Lake will continue to recede. Restriction of the pool level to less than 325.5-m elevation is the least expensive solution to the problem.
    Type of Medium: Series available for loan
    Pages: ix, 110 Seiten , Illustrationen
    Series Statement: CRREL Report 84-32
    Language: English
    Note: CONTENTS Abstract Preface Summary Chapter 1. Introduction Location Purpose of study Previous work Chapter 2. Methodology Geology Overland erosion Wave erosion Frost penetration and heave Thaw failure Bank recession Ground water Soil moisture Chapter 3. Results Geology Geotechnical properties Overland erosion Wave erosion Freeze-thaw phenomena Ground water fluctuations Other slope failures Chapter 4. Discussion Overland erosion Wave erosion Thaw failure Universal soil loss equation Chapter 5. Summary and conclusions Techniques Erosion processes at Orwell lake Bank recession Literature cited Appendix A1: Average cumulative change of surface at erosion stations #2-12, 1980-81 Appendix A2: Cumulative net changes at overland erosion stations #1-12, 1980-81 Appendix A3: Cumulative net changes at overland erosion stations #1 -12, 198 1-82 Appendix A4: Cumulative average erosion at overland erosion stations #1-12, 1980-81 Appendix AS: Cumulative average erosion at overland erosion stations #1-12, 1981-82 Appendix A6: Cumulative average erosion at overland erosion stations #1 -1 2A, 1982 Appendix B: Dimensions of erosion sections, Orwell Lake, Minnesota Appendix C: Piezometer installation data, Orwell Lake, Minneso
    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-201-84/33
    In: CRREL Report, 84-33
    Description / Table of Contents: A small-scale experimental study was conducted to characterize the magnitude and nature of ice forces during continuous crushing of ice against a rigid, vertical, cylindrical structure. The diameter of the structure was varied from 50 to 500 mm, the relative velocity from 10 to 210 mm/s, and the ice thickness from 50 to 80 mm. The ice tended to fail repetitively, with the frequency of failure termed the characteristic frequency. The characteristic frequency varied linearly with velocity and to a small extent with structure diameter. The size of the damage zone was 10 to 50% of the ice thickness, with an average value of 30%. The maximum and mean normalized ice forces were strongly dependent on the aspect ratio (structure diameter/ice thickness). The forces increased significantly with decreasing aspect ratio, but were constant for large aspect ratios. The maximum normalized forces appeared to be independent of strain rate. The effect of velocity on the normalized ice forces depended on structure diameter. The mean effective pressure or specific energy of ice crushing depended on both aspect ratio and ice-structure relative velocity. The energy required to crush the ice for the one failure cycle was obtained from the ice force records for each test, and was compared to the energy calculated from an idealized sawtooth shape for the force record, the maximum force, velocity and characteristic frequency data. Originator - supplied keywords included: Cold regions, Cold regions construction, Cylindrical test structures, Ice, Ice crushing, Ice forces, and Test facilities.
    Type of Medium: Series available for loan
    Pages: vi, 47 Seiten , Illustrationen
    Series Statement: CRREL Report 84-33
    Language: English
    Note: Contents Abstract Preface Nomenclature Introduction Test objectives Experimental setup and procedures Facilities Test fixture Data acquisiton system Ice sheets Measurement of ice properties Daily test summary Experimental results and discussion Observations Ice force records Frequency of ice force variations Discussion Maximum crushing forces Mean effective pressure or specific energy of ice in crushing Failure energy of ice Ratio of maximum force to mean force Summary and conclusions Literature cited Appendix A: Data for continuous crushing tests
    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-201-80/6
    In: CRREL Report, 80-6
    Description / Table of Contents: Weekly measurements of the thickness of lake, river and fast sea ice made over a period of 10 to 15 years at 66 locations in Canada and Alaska are analyzed, and the portion of the data relating to maximum ice thickness and decay (i.e. the decrease in ice thickness) is examined. Ice thickness curves revealed individual patterns of ice decay, and comparisons between locations disclosed major contrasts in the amount of ice accretion and the times of maximum ice and ice clearance. Although many factors affect the ice decay process, this study investigates in detail the effect of thawing temperatures. Concurrent measurements of the air temperature at each location made it possible to analyze the relationship between accumulated thawing degree-days (ATDD) and ice cover decay. Other factors affecting ice ablation and breakup, such as snow-ice formation, snow cover depth, solar radiation and wind are also discussed.
    Type of Medium: Series available for loan
    Pages: v, 160 Seiten , Illustrationen
    Series Statement: CRREL Report 80-6
    Language: English
    Note: CONTENTS Abstract Preface Introduction Data sources and literature review Canada Alaska Data tabulation Station selection Description of tabulated data Station location and ice measurement site descriptions Review of previous studies on maximum ice in North America Maximum ice thickness maps Date of maximum ice Plotting of the ice decay curves General procedures Categories of water bodies Ice decay at sea ice locations Envelope curves Average curves Snow-ice formation Ice decay at lake ice locations Average curves Regional variations and similarities Ice decay at river ice locations Variations in ice thickness Rapid ice clearance Comparison between Alaskan and Canadian river ice decay curves Incremental extraction of ice decay data for analysis purposes Selection of ice decay intervals Preliminary evaluation of the methodology Further considerations of the methodology Relationships between ice decay and thawing air temperatures Average daily vs maximum daily air temperature 10-day increments vs accumulated values Total years vs year-to-year analysis Evaluation of use of 0°C as a base Final format of the relationship between ice decay and ATDD Evaluation of the final form Possible causes for variations in slope values Decreasing sea ice thickness and thawing air temperatures Factors affecting sea ice decay Relationship between ATDD and sea ice decay Influence of solar radiation and wind on sea ice decay Literature cited Selected bibliography Appendix A. Ice thickness measurements and other related (or associated) observations for stations in Canada and Alaska Appendix B. Maps of least and greatest ice thickness observed at the time of maximum growth, and average date of occurrence Appendix C. Annual ice decay curves for stations in Canada and Alaska
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 99
    Call number: ZSP-201-80/19
    In: CRREL Report, 80-19
    Description / Table of Contents: During the period 1975-1978 the Federal Highway Administration sponsored a series of environmental engineering in­vestigations along the Yukon River to Prudhoe Bay Haul Road. In 1976 the Department of Energy joined these in­vestigations with a series of ecological projects which continue to the present. Both agencies research efforts were con­ducted on a cooperative basis with CRREL’s in-house research program. The objectives of the research focused on 1) an evaluation of the performance of the road, 2) an assessment of changes in the environment associated with the road, 3) documentation of flora and vegetation along the 577-km-long transect, 4) methodologies for revegetation and restoration, and 5) an assessment of biological parameters as indicators of environmental integrity. In support of these objectives, specific studies were undertaken that investigated the climate along the road, thaw and subsidence beneath and adjacent to the road, drainage and side slope performance, distribution and properties of road dust, vegetation distribution, vegetation disturbance and recovery, occurrence of weeds and weedy species, erosion and its control, revegetation and restoration, and construction of the fuel gas line. This report presents background, information on the region, detailed results of the road thaw subsidence and dust investigations, and summaries of revegetation, fuel gas line, vegetation distribution, soil, and weed studies.
    Type of Medium: Series available for loan
    Pages: xv, 187 Seiten , Illustrationen
    Series Statement: CRREL Report 80-19
    Language: English
    Note: CONTENTS Abstract Preface Summary Introduction Chapter 1. The road and its environment Introduction General physiography Regional climate Surficial and bedrock geology Permafrost and ground ice General biota Vegetation Floristic survey Vegetation mapping Soils and mapping Chapter 2. Roadbed performance and associated investigations Roadbed investigations Roadbed performance Performance of drainage features Performance of sideslopes Conclusions from road, drainage and sideslope performance studies Fuel gas line construction Chapter 3. Distribution and properties of road dust along the northern portion of the Haul Road Introduction Methods Results of wind direction and velocity measurements Dust load and distribution Particle size analyses of dust Chemical composition properties of dust and related samples Soil cation composition Dust impacts on vegetation Discussion and conclusions Chapter 4. Revegetation and restoration investigations Introduction Revegetation approaches Alyeska erosion control and revegetation program Weeds and weedy plants Performance of revegetation Alyeska willow cutting program CRREL restoration experiments Conclusions Revegetation recommendations General report recommendations Literature cited Appendix A: General environmental guidelines applicable to subarctic and arctic road construction Appendix B: University-based studies along the Yukon River-Prudhoe Bay Haul Road Appendix C: CRREL maps of Haul Road showing locations of all study Sites Appendix D: Additional Haul Road cross-sectional profiles Appendix E: Clay mineralogy of road-related materials Appendix F: List of reports in the Joint State/Federal Fish and Wildlife Ad­visory Team series
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 100
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-201-80/16
    In: CRREL Report, 80-16
    Description / Table of Contents: Eight species of loricate choanoflagellates (Acanthoccidae), Acanthoecopsis spiculifera, Bicosta spinifera, Bicosta antennigera, Callicantha simplex, Calliacantha multispina aff., Crinolina aperta, Diaphanoeca multionnulata, and Parvicorbicula socialis, were observed in samples obtained from the Weddell Sea during the austral summer, 1977. D. multiannulata was described for the first time from these samples; the other organisms have either been described previously or are being described at this time. The distribution of most species within the Weddell Sea was widespread. The distributional, environmental, and morphological range of A. spiculifera, B. spinifera, C. aperta, and P. socialis was expanded. Habitats in which choanoflagellates were found included the water column, the edges of ice floes, ponds on ice floes, and the interiors of ice floes. The presence of choanoflagellates within the ice indicates that there may be a closely coupled trophic relationship with the other two biological components of the ice community, the ice algae and the bacteria. The presence in the ice of seven species with both a caudal appendage and anterior projections suggests a positive relationship between this lorica configuration and the ice habitat. Mechanisms of variance of transverse costal diameters between genera may be useful to the taxonomy and phylogeny of this family.
    Type of Medium: Series available for loan
    Pages: vi, 26 Seiten , Illustrationen
    Series Statement: CRREL Report 80-16
    Language: English
    Note: CONTENTS Introduction Literature review Objectives Materials and methods Results Observations Distribution and environmental tolerances Discussion Morphology Distribution Habitat Summary Conclusions Recommendations for future work Literature cited Appendix A Type descriptions of Acanthoecidae collected from the Weddell Sea
    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...