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This study investigates the relative influence of various parameters on the kinetic friction coefficient mu sub k between ice and different surfaces. Friction tests were performed with urea-doped, columnar ice, studying the parameters of normal pressure, velocity, type of material, material roughness, ice orientation, ice hardness and test configuration. Tests were conducted by pulling a sample of ice over a sheet of material and by pulling a sample of material over an ice sheet. An ambient temperature of -1.5 + or - 1 deg C was maintained throughout, and the ice surface hardness was measured using a specially designed apparatus. The results of the friction tests revealed that the behavior of mu sub k with varying velocity was significantly influenced by the test configuration and material roughness. The magnitude of the kinetic friction coefficient was also affected by varying normal pressure, surface roughness and ice hardness. Additional guidelines for standardized ice friction tests and future investigations were recommended.
This report presents the first series of conventional triaxial tests carried out on columnar first year sea ice samples obtained from the field and tested under controlled laboratory conditions using a large-capacity test machine. A total of 110 horizontal ice samples from Prudhoe Bay, Alaska, were tested on a closed-loop electro-hydraulic test machine at -10 C in unconfined and confined constant-strain-rate compression. The confined tests were conducted in a conventional triaxial cell that maintained a constant ratio between the radial and axial stress to simulate in situ loading conditions. The load ratios used were 0.25, 0.50 and 0.75. The strain rate of each test was constant at 0.01, 0.001, or 0.00001/s. Data are presented on the strength, failure strain and initial tangent modulus of the first year sea ice under these loading conditions. The effects of confining pressure, strain rate and ice structure on the mechanical properties of the ice are examined.
Relates to U.S. Dept. of the Interior's proposed sale 71, the second major Beaufort Sea lease sale. Sale 71 area located on Alaskan arctic coast. Two sections: characterization of Sale 71 environments, and interdisciplinary process analyses, impact predictions, and issue discussions.
Remote Sensing of Sea Ice in the Northern Sea Route: Studies and Applications initially provides a history of the Northern Sea Route as an important strategic transport route for supporting the northern regions of Russia and cargo transportation between Europe and the Northern Pacific Basin. The authors then describe sea ice conditions in the Eurasian Arctic Seas and, using microwave satellite data, provide a detailed analysis of difficult sea ice conditions. Remote sensing techniques and the basic principles of SAR image formation are described, as well as the major satellite radar systems used for ice studies in the Arctic. The authors take a good look at the use of sensing equipment in experiments, including the ICE WATCH project used for monitoring the Northern Sea Route. The possibilities of using SAR remote sensing for ice navigation in the Northern Sea Route is also detailed, analysing techniques of automatic image processing and interpretation. A study is provided of regional drifting ice, fast ice and river ice in the coastal areas of the Arctic Seas. The book concludes with a review of the practical experience using SAR images for supporting navigation and offshore industrial activity, based on a series of experiments conducted with the Murmansk Shipping Company on board nuclear icebreakers.