CONFINED CREEP TESTS ON POLAR SNOW

• Main Authors: Mellor,Malcolm, Hendrickson,George
• Other Authors: COLD REGIONS RESEARCH AND ENGINEERING LAB HANOVER N H
• Format: Text
• Language: English
• Published: 1965
• Subjects: (*SNOW; CREEP); (*CREEP; SNOW); DENSITY; TEMPERATURE; PLASTIC PROPERTIES; VISCOSITY; COMPRESSIVE PROPERTIES; TEST METHODS; TEST EQUIPMENT; PIPES; POLAR REGIONS; Amundsen-Scott; Byrd; Yoke; Antarc*; Antarctica; Ice Sheet
• Online Access: http://www.dtic.mil/docs/citations/AD0613043; http://oai.dtic.mil/oai/oai?&verb=getRecord&metadataPrefix=html&identifier=AD0613043

Snow was sampled from various depths below the surface of the ice sheet at Byrd and Amundsen-Scott Stations, Antarctica. The samples were obtained either by sawing blocks from trench and tunnel walls or by coring with the CRREL hand auger. The creep specimens were introduced into their stainless-steel cylinders by 'screwing' the saw-edged cylinders into larger sample blocks. The cylinders were standard CRREL snowsampling tubes, lined with silicone grease to reduce friction and adhesion. The tubes were set vertically on a bench, and pressure was applied axially with a loose piston loaded by a guided yoke, deformations being read periodically from dial micrometers. The mechanics of creep is discussed and the data are tabulated and graphed with respect to temperature and density effects. At the lower densities, the compressive viscosities are in reasonable agreement with those deduced from depthdensity profiles. At the higher densities, the viscosities are significantly lower than those calculated from depthdensity profiles. It is suggested that at least part of the discrepancy may be attributed to the strain history of the snow. The creep tests suggest a functional relationship between viscosity and density different from that suggested by analyses of natural snow densification. (Author)